diff options
Diffstat (limited to 'src/jdk/nashorn/internal/codegen/CodeGenerator.java')
| -rw-r--r-- | src/jdk/nashorn/internal/codegen/CodeGenerator.java | 4949 |
1 files changed, 3475 insertions, 1474 deletions
diff --git a/src/jdk/nashorn/internal/codegen/CodeGenerator.java b/src/jdk/nashorn/internal/codegen/CodeGenerator.java index 52bdc7cb..59aa258e 100644 --- a/src/jdk/nashorn/internal/codegen/CodeGenerator.java +++ b/src/jdk/nashorn/internal/codegen/CodeGenerator.java @@ -29,13 +29,12 @@ import static jdk.nashorn.internal.codegen.ClassEmitter.Flag.PRIVATE; import static jdk.nashorn.internal.codegen.ClassEmitter.Flag.STATIC; import static jdk.nashorn.internal.codegen.CompilerConstants.ARGUMENTS; import static jdk.nashorn.internal.codegen.CompilerConstants.CALLEE; +import static jdk.nashorn.internal.codegen.CompilerConstants.CREATE_PROGRAM_FUNCTION; import static jdk.nashorn.internal.codegen.CompilerConstants.GET_MAP; import static jdk.nashorn.internal.codegen.CompilerConstants.GET_STRING; import static jdk.nashorn.internal.codegen.CompilerConstants.QUICK_PREFIX; import static jdk.nashorn.internal.codegen.CompilerConstants.REGEX_PREFIX; -import static jdk.nashorn.internal.codegen.CompilerConstants.RETURN; import static jdk.nashorn.internal.codegen.CompilerConstants.SCOPE; -import static jdk.nashorn.internal.codegen.CompilerConstants.SPLIT_ARRAY_ARG; import static jdk.nashorn.internal.codegen.CompilerConstants.SPLIT_PREFIX; import static jdk.nashorn.internal.codegen.CompilerConstants.THIS; import static jdk.nashorn.internal.codegen.CompilerConstants.VARARGS; @@ -45,25 +44,40 @@ import static jdk.nashorn.internal.codegen.CompilerConstants.methodDescriptor; import static jdk.nashorn.internal.codegen.CompilerConstants.staticCallNoLookup; import static jdk.nashorn.internal.codegen.CompilerConstants.typeDescriptor; import static jdk.nashorn.internal.codegen.CompilerConstants.virtualCallNoLookup; +import static jdk.nashorn.internal.codegen.ObjectClassGenerator.OBJECT_FIELDS_ONLY; +import static jdk.nashorn.internal.ir.Symbol.HAS_SLOT; import static jdk.nashorn.internal.ir.Symbol.IS_INTERNAL; -import static jdk.nashorn.internal.ir.Symbol.IS_TEMP; +import static jdk.nashorn.internal.runtime.UnwarrantedOptimismException.INVALID_PROGRAM_POINT; +import static jdk.nashorn.internal.runtime.UnwarrantedOptimismException.isValid; +import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_APPLY_TO_CALL; +import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_DECLARE; import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_FAST_SCOPE; +import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_OPTIMISTIC; +import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_PROGRAM_POINT_SHIFT; import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_SCOPE; -import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_STRICT; import java.io.PrintWriter; +import java.util.ArrayDeque; import java.util.ArrayList; import java.util.Arrays; +import java.util.BitSet; +import java.util.Collection; +import java.util.Collections; +import java.util.Deque; import java.util.EnumSet; +import java.util.HashMap; import java.util.HashSet; import java.util.Iterator; import java.util.LinkedList; import java.util.List; +import java.util.Map; import java.util.Set; import java.util.TreeMap; +import java.util.function.Supplier; +import jdk.nashorn.internal.AssertsEnabled; +import jdk.nashorn.internal.IntDeque; import jdk.nashorn.internal.codegen.ClassEmitter.Flag; import jdk.nashorn.internal.codegen.CompilerConstants.Call; -import jdk.nashorn.internal.codegen.RuntimeCallSite.SpecializedRuntimeNode; import jdk.nashorn.internal.codegen.types.ArrayType; import jdk.nashorn.internal.codegen.types.Type; import jdk.nashorn.internal.ir.AccessNode; @@ -83,22 +97,30 @@ import jdk.nashorn.internal.ir.ExpressionStatement; import jdk.nashorn.internal.ir.ForNode; import jdk.nashorn.internal.ir.FunctionNode; import jdk.nashorn.internal.ir.FunctionNode.CompilationState; +import jdk.nashorn.internal.ir.GetSplitState; import jdk.nashorn.internal.ir.IdentNode; import jdk.nashorn.internal.ir.IfNode; import jdk.nashorn.internal.ir.IndexNode; +import jdk.nashorn.internal.ir.JoinPredecessorExpression; +import jdk.nashorn.internal.ir.JumpStatement; +import jdk.nashorn.internal.ir.LabelNode; import jdk.nashorn.internal.ir.LexicalContext; import jdk.nashorn.internal.ir.LexicalContextNode; import jdk.nashorn.internal.ir.LiteralNode; import jdk.nashorn.internal.ir.LiteralNode.ArrayLiteralNode; import jdk.nashorn.internal.ir.LiteralNode.ArrayLiteralNode.ArrayUnit; +import jdk.nashorn.internal.ir.LiteralNode.PrimitiveLiteralNode; +import jdk.nashorn.internal.ir.LocalVariableConversion; import jdk.nashorn.internal.ir.LoopNode; import jdk.nashorn.internal.ir.Node; import jdk.nashorn.internal.ir.ObjectNode; +import jdk.nashorn.internal.ir.Optimistic; import jdk.nashorn.internal.ir.PropertyNode; import jdk.nashorn.internal.ir.ReturnNode; import jdk.nashorn.internal.ir.RuntimeNode; import jdk.nashorn.internal.ir.RuntimeNode.Request; -import jdk.nashorn.internal.ir.SplitNode; +import jdk.nashorn.internal.ir.SetSplitState; +import jdk.nashorn.internal.ir.SplitReturn; import jdk.nashorn.internal.ir.Statement; import jdk.nashorn.internal.ir.SwitchNode; import jdk.nashorn.internal.ir.Symbol; @@ -117,20 +139,26 @@ import jdk.nashorn.internal.parser.Lexer.RegexToken; import jdk.nashorn.internal.parser.TokenType; import jdk.nashorn.internal.runtime.Context; import jdk.nashorn.internal.runtime.Debug; -import jdk.nashorn.internal.runtime.DebugLogger; import jdk.nashorn.internal.runtime.ECMAException; import jdk.nashorn.internal.runtime.JSType; -import jdk.nashorn.internal.runtime.Property; +import jdk.nashorn.internal.runtime.OptimisticReturnFilters; import jdk.nashorn.internal.runtime.PropertyMap; import jdk.nashorn.internal.runtime.RecompilableScriptFunctionData; +import jdk.nashorn.internal.runtime.RewriteException; import jdk.nashorn.internal.runtime.Scope; +import jdk.nashorn.internal.runtime.ScriptEnvironment; import jdk.nashorn.internal.runtime.ScriptFunction; import jdk.nashorn.internal.runtime.ScriptObject; import jdk.nashorn.internal.runtime.ScriptRuntime; import jdk.nashorn.internal.runtime.Source; import jdk.nashorn.internal.runtime.Undefined; +import jdk.nashorn.internal.runtime.UnwarrantedOptimismException; import jdk.nashorn.internal.runtime.arrays.ArrayData; import jdk.nashorn.internal.runtime.linker.LinkerCallSite; +import jdk.nashorn.internal.runtime.logging.DebugLogger; +import jdk.nashorn.internal.runtime.logging.Loggable; +import jdk.nashorn.internal.runtime.logging.Logger; +import jdk.nashorn.internal.runtime.options.Options; /** * This is the lowest tier of the code generator. It takes lowered ASTs emitted @@ -151,16 +179,44 @@ import jdk.nashorn.internal.runtime.linker.LinkerCallSite; * The CodeGenerator visits nodes only once, tags them as resolved and emits * bytecode for them. */ -final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContext> { +@Logger(name="codegen") +final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContext> implements Loggable { + + private static final Type SCOPE_TYPE = Type.typeFor(ScriptObject.class); private static final String GLOBAL_OBJECT = Type.getInternalName(Global.class); - private static final String SCRIPTFUNCTION_IMPL_OBJECT = Type.getInternalName(ScriptFunctionImpl.class); + private static final String SCRIPTFUNCTION_IMPL_NAME = Type.getInternalName(ScriptFunctionImpl.class); + private static final Type SCRIPTFUNCTION_IMPL_TYPE = Type.typeFor(ScriptFunction.class); + + private static final Call CREATE_REWRITE_EXCEPTION = CompilerConstants.staticCallNoLookup(RewriteException.class, + "create", RewriteException.class, UnwarrantedOptimismException.class, Object[].class, String[].class); + private static final Call CREATE_REWRITE_EXCEPTION_REST_OF = CompilerConstants.staticCallNoLookup(RewriteException.class, + "create", RewriteException.class, UnwarrantedOptimismException.class, Object[].class, String[].class, int[].class); + + private static final Call ENSURE_INT = CompilerConstants.staticCallNoLookup(OptimisticReturnFilters.class, + "ensureInt", int.class, Object.class, int.class); + private static final Call ENSURE_LONG = CompilerConstants.staticCallNoLookup(OptimisticReturnFilters.class, + "ensureLong", long.class, Object.class, int.class); + private static final Call ENSURE_NUMBER = CompilerConstants.staticCallNoLookup(OptimisticReturnFilters.class, + "ensureNumber", double.class, Object.class, int.class); + + private static final Class<?> ITERATOR_CLASS = Iterator.class; + static { + assert ITERATOR_CLASS == CompilerConstants.ITERATOR_PREFIX.type(); + } + private static final Type ITERATOR_TYPE = Type.typeFor(ITERATOR_CLASS); + private static final Type EXCEPTION_TYPE = Type.typeFor(CompilerConstants.EXCEPTION_PREFIX.type()); + + private static final Integer INT_ZERO = Integer.valueOf(0); /** Constant data & installation. The only reason the compiler keeps this is because it is assigned * by reflection in class installation */ private final Compiler compiler; + /** Is the current code submitted by 'eval' call? */ + private final boolean evalCode; + /** Call site flags given to the code generator to be used for all generated call sites */ private final int callSiteFlags; @@ -180,22 +236,48 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex /** Current compile unit */ private CompileUnit unit; - private static final DebugLogger LOG = new DebugLogger("codegen", "nashorn.codegen.debug"); + private final DebugLogger log; /** From what size should we use spill instead of fields for JavaScript objects? */ - private static final int OBJECT_SPILL_THRESHOLD = 300; + private static final int OBJECT_SPILL_THRESHOLD = Options.getIntProperty("nashorn.spill.threshold", 256); private final Set<String> emittedMethods = new HashSet<>(); + // Function Id -> ContinuationInfo. Used by compilation of rest-of function only. + private final Map<Integer, ContinuationInfo> fnIdToContinuationInfo = new HashMap<>(); + + private final Deque<Label> scopeEntryLabels = new ArrayDeque<>(); + + private static final Label METHOD_BOUNDARY = new Label(""); + private final Deque<Label> catchLabels = new ArrayDeque<>(); + // Number of live locals on entry to (and thus also break from) labeled blocks. + private final IntDeque labeledBlockBreakLiveLocals = new IntDeque(); + + //is this a rest of compilation + private final int[] continuationEntryPoints; + /** * Constructor. * * @param compiler */ - CodeGenerator(final Compiler compiler) { + CodeGenerator(final Compiler compiler, final int[] continuationEntryPoints) { super(new CodeGeneratorLexicalContext()); - this.compiler = compiler; - this.callSiteFlags = compiler.getEnv()._callsite_flags; + this.compiler = compiler; + this.evalCode = compiler.getSource().isEvalCode(); + this.continuationEntryPoints = continuationEntryPoints; + this.callSiteFlags = compiler.getScriptEnvironment()._callsite_flags; + this.log = initLogger(compiler.getContext()); + } + + @Override + public DebugLogger getLogger() { + return log; + } + + @Override + public DebugLogger initLogger(final Context context) { + return context.getLogger(this.getClass()); } /** @@ -205,7 +287,15 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex * @return the correct flags for a call site in the current function */ int getCallSiteFlags() { - return lc.getCurrentFunction().isStrict() ? callSiteFlags | CALLSITE_STRICT : callSiteFlags; + return lc.getCurrentFunction().getCallSiteFlags() | callSiteFlags; + } + + /** + * Are we generating code for 'eval' code? + * @return true if currently compiled code is 'eval' code. + */ + boolean isEvalCode() { + return evalCode; } /** @@ -214,38 +304,79 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex * @param identNode an identity node to load * @return the method generator used */ - private MethodEmitter loadIdent(final IdentNode identNode, final Type type) { + private MethodEmitter loadIdent(final IdentNode identNode, final TypeBounds resultBounds) { + checkTemporalDeadZone(identNode); final Symbol symbol = identNode.getSymbol(); if (!symbol.isScope()) { + final Type type = identNode.getType(); + if(type == Type.UNDEFINED) { + return method.loadUndefined(resultBounds.widest); + } + assert symbol.hasSlot() || symbol.isParam(); - return method.load(symbol).convert(type); + return method.load(identNode); } - final String name = symbol.getName(); - final Source source = lc.getCurrentFunction().getSource(); - - if (CompilerConstants.__FILE__.name().equals(name)) { - return method.load(source.getName()); - } else if (CompilerConstants.__DIR__.name().equals(name)) { - return method.load(source.getBase()); - } else if (CompilerConstants.__LINE__.name().equals(name)) { - return method.load(source.getLine(identNode.position())).convert(Type.OBJECT); + assert identNode.getSymbol().isScope() : identNode + " is not in scope!"; + final int flags = CALLSITE_SCOPE | getCallSiteFlags(); + if (isFastScope(symbol)) { + // Only generate shared scope getter for fast-scope symbols so we know we can dial in correct scope. + if (symbol.getUseCount() > SharedScopeCall.FAST_SCOPE_GET_THRESHOLD && !isOptimisticOrRestOf()) { + method.loadCompilerConstant(SCOPE); + // As shared scope vars are only used in non-optimistic compilation, we switch from using TypeBounds to + // just a single definitive type, resultBounds.widest. + loadSharedScopeVar(resultBounds.widest, symbol, flags); + } else { + new LoadFastScopeVar(identNode, resultBounds, flags).emit(); + } } else { - assert identNode.getSymbol().isScope() : identNode + " is not in scope!"; + //slow scope load, we have no proto depth + new LoadScopeVar(identNode, resultBounds, flags).emit(); + } - final int flags = CALLSITE_SCOPE | getCallSiteFlags(); - method.loadCompilerConstant(SCOPE); + return method; + } + + // Any access to LET and CONST variables before their declaration must throw ReferenceError. + // This is called the temporal dead zone (TDZ). See https://gist.github.com/rwaldron/f0807a758aa03bcdd58a + private void checkTemporalDeadZone(final IdentNode identNode) { + if (identNode.isDead()) { + method.load(identNode.getSymbol().getName()); + method.invoke(ScriptRuntime.THROW_REFERENCE_ERROR); + } + } - if (isFastScope(symbol)) { - // Only generate shared scope getter for fast-scope symbols so we know we can dial in correct scope. - if (symbol.getUseCount() > SharedScopeCall.FAST_SCOPE_GET_THRESHOLD) { - return loadSharedScopeVar(type, symbol, flags); + private boolean isRestOf() { + return continuationEntryPoints != null; + } + + private boolean isOptimisticOrRestOf() { + return useOptimisticTypes() || isRestOf(); + } + + private boolean isCurrentContinuationEntryPoint(final int programPoint) { + return isRestOf() && getCurrentContinuationEntryPoint() == programPoint; + } + + private int[] getContinuationEntryPoints() { + return isRestOf() ? continuationEntryPoints : null; + } + + private int getCurrentContinuationEntryPoint() { + return isRestOf() ? continuationEntryPoints[0] : INVALID_PROGRAM_POINT; + } + + private boolean isContinuationEntryPoint(final int programPoint) { + if (isRestOf()) { + assert continuationEntryPoints != null; + for (final int cep : continuationEntryPoints) { + if (cep == programPoint) { + return true; } - return loadFastScopeVar(type, symbol, flags, identNode.isFunction()); } - return method.dynamicGet(type, identNode.getName(), flags, identNode.isFunction()); } + return false; } /** @@ -285,7 +416,7 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex } previousWasBlock = true; } else { - if ((node instanceof WithNode && previousWasBlock) || (node instanceof FunctionNode && CodeGeneratorLexicalContext.isFunctionDynamicScope((FunctionNode)node))) { + if (node instanceof WithNode && previousWasBlock || node instanceof FunctionNode && ((FunctionNode)node).needsDynamicScope()) { // If we hit a scope that can have symbols introduced into it at run time before finding the defining // block, the symbol can't be fast scoped. A WithNode only counts if we've immediately seen a block // before - its block. Otherwise, we are currently processing the WithNode's expression, and that's @@ -300,40 +431,89 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex } private MethodEmitter loadSharedScopeVar(final Type valueType, final Symbol symbol, final int flags) { - method.load(isFastScope(symbol) ? getScopeProtoDepth(lc.getCurrentBlock(), symbol) : -1); - final SharedScopeCall scopeCall = lc.getScopeGet(unit, valueType, symbol, flags | CALLSITE_FAST_SCOPE); - return scopeCall.generateInvoke(method); + assert !isOptimisticOrRestOf(); + if (isFastScope(symbol)) { + method.load(getScopeProtoDepth(lc.getCurrentBlock(), symbol)); + } else { + method.load(-1); + } + return lc.getScopeGet(unit, symbol, valueType, flags | CALLSITE_FAST_SCOPE).generateInvoke(method); } - private MethodEmitter loadFastScopeVar(final Type valueType, final Symbol symbol, final int flags, final boolean isMethod) { - loadFastScopeProto(symbol, false); - return method.dynamicGet(valueType, symbol.getName(), flags | CALLSITE_FAST_SCOPE, isMethod); + private class LoadScopeVar extends OptimisticOperation { + final IdentNode identNode; + private final int flags; + + LoadScopeVar(final IdentNode identNode, final TypeBounds resultBounds, final int flags) { + super(identNode, resultBounds); + this.identNode = identNode; + this.flags = flags; + } + + @Override + void loadStack() { + method.loadCompilerConstant(SCOPE); + getProto(); + } + + void getProto() { + //empty + } + + @Override + void consumeStack() { + // If this is either __FILE__, __DIR__, or __LINE__ then load the property initially as Object as we'd convert + // it anyway for replaceLocationPropertyPlaceholder. + if(identNode.isCompileTimePropertyName()) { + method.dynamicGet(Type.OBJECT, identNode.getSymbol().getName(), flags, identNode.isFunction(), false); + replaceCompileTimeProperty(); + } else { + dynamicGet(identNode.getSymbol().getName(), flags, identNode.isFunction(), false); + } + } + } + + private class LoadFastScopeVar extends LoadScopeVar { + LoadFastScopeVar(final IdentNode identNode, final TypeBounds resultBounds, final int flags) { + super(identNode, resultBounds, flags | CALLSITE_FAST_SCOPE); + } + + @Override + void getProto() { + loadFastScopeProto(identNode.getSymbol(), false); + } } private MethodEmitter storeFastScopeVar(final Symbol symbol, final int flags) { loadFastScopeProto(symbol, true); - method.dynamicSet(symbol.getName(), flags | CALLSITE_FAST_SCOPE); + method.dynamicSet(symbol.getName(), flags | CALLSITE_FAST_SCOPE, false); return method; } private int getScopeProtoDepth(final Block startingBlock, final Symbol symbol) { + //walk up the chain from starting block and when we bump into the current function boundary, add the external + //information. + final FunctionNode fn = lc.getCurrentFunction(); + final int externalDepth = compiler.getScriptFunctionData(fn.getId()).getExternalSymbolDepth(symbol.getName()); + + //count the number of scopes from this place to the start of the function + + final int internalDepth = FindScopeDepths.findInternalDepth(lc, fn, startingBlock, symbol); + final int scopesToStart = FindScopeDepths.findScopesToStart(lc, fn, startingBlock); int depth = 0; - final String name = symbol.getName(); - for(final Iterator<Block> blocks = lc.getBlocks(startingBlock); blocks.hasNext();) { - final Block currentBlock = blocks.next(); - if (currentBlock.getExistingSymbol(name) == symbol) { - return depth; - } - if (currentBlock.needsScope()) { - ++depth; - } + if (internalDepth == -1) { + depth = scopesToStart + externalDepth; + } else { + assert internalDepth <= scopesToStart; + depth = internalDepth; } - return -1; + + return depth; } private void loadFastScopeProto(final Symbol symbol, final boolean swap) { final int depth = getScopeProtoDepth(lc.getCurrentBlock(), symbol); - assert depth != -1; + assert depth != -1 : "Couldn't find scope depth for symbol " + symbol.getName() + " in " + lc.getCurrentFunction(); if (depth > 0) { if (swap) { method.swap(); @@ -348,29 +528,36 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex } /** - * Generate code that loads this node to the stack. This method is only - * public to be accessible from the maps sub package. Do not call externally + * Generate code that loads this node to the stack, not constraining its type * - * @param node node to load + * @param expr node to load * * @return the method emitter used */ - MethodEmitter load(final Expression node) { - return load(node, node.hasType() ? node.getType() : null, false); + private MethodEmitter loadExpressionUnbounded(final Expression expr) { + return loadExpression(expr, TypeBounds.UNBOUNDED); + } + + private MethodEmitter loadExpressionAsObject(final Expression expr) { + return loadExpression(expr, TypeBounds.OBJECT); + } + + MethodEmitter loadExpressionAsBoolean(final Expression expr) { + return loadExpression(expr, TypeBounds.BOOLEAN); } // Test whether conversion from source to target involves a call of ES 9.1 ToPrimitive // with possible side effects from calling an object's toString or valueOf methods. - private boolean noToPrimitiveConversion(final Type source, final Type target) { + private static boolean noToPrimitiveConversion(final Type source, final Type target) { // Object to boolean conversion does not cause ToPrimitive call return source.isJSPrimitive() || !target.isJSPrimitive() || target.isBoolean(); } - MethodEmitter loadBinaryOperands(final Expression lhs, final Expression rhs, final Type type) { - return loadBinaryOperands(lhs, rhs, type, false); + MethodEmitter loadBinaryOperands(final BinaryNode binaryNode) { + return loadBinaryOperands(binaryNode.lhs(), binaryNode.rhs(), TypeBounds.UNBOUNDED.notWiderThan(binaryNode.getWidestOperandType()), false, false); } - private MethodEmitter loadBinaryOperands(final Expression lhs, final Expression rhs, final Type type, final boolean baseAlreadyOnStack) { + private MethodEmitter loadBinaryOperands(final Expression lhs, final Expression rhs, final TypeBounds explicitOperandBounds, final boolean baseAlreadyOnStack, final boolean forceConversionSeparation) { // ECMAScript 5.1 specification (sections 11.5-11.11 and 11.13) prescribes that when evaluating a binary // expression "LEFT op RIGHT", the order of operations must be: LOAD LEFT, LOAD RIGHT, CONVERT LEFT, CONVERT // RIGHT, EXECUTE OP. Unfortunately, doing it in this order defeats potential optimizations that arise when we @@ -381,38 +568,154 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex // a primitive value, or RIGHT is an expression that loads without side effects, then we can do the // reordering and collapse LOAD/CONVERT into a single operation; otherwise we need to do the more costly // separate operations to preserve specification semantics. - if (noToPrimitiveConversion(lhs.getType(), type) || rhs.isLocal()) { - // Can reorder. Combine load and convert into single operations. - load(lhs, type, baseAlreadyOnStack); - load(rhs, type, false); + + // Operands' load type should not be narrower than the narrowest of the individual operand types, nor narrower + // than the lower explicit bound, but it should also not be wider than + final Type lhsType = undefinedToNumber(lhs.getType()); + final Type rhsType = undefinedToNumber(rhs.getType()); + final Type narrowestOperandType = Type.narrowest(Type.widest(lhsType, rhsType), explicitOperandBounds.widest); + final TypeBounds operandBounds = explicitOperandBounds.notNarrowerThan(narrowestOperandType); + if (noToPrimitiveConversion(lhsType, explicitOperandBounds.widest) || rhs.isLocal()) { + // Can reorder. We might still need to separate conversion, but at least we can do it with reordering + if (forceConversionSeparation) { + // Can reorder, but can't move conversion into the operand as the operation depends on operands + // exact types for its overflow guarantees. E.g. with {L}{%I}expr1 {L}* {L}{%I}expr2 we are not allowed + // to merge {L}{%I} into {%L}, as that can cause subsequent overflows; test for JDK-8058610 contains + // concrete cases where this could happen. + final TypeBounds safeConvertBounds = TypeBounds.UNBOUNDED.notNarrowerThan(narrowestOperandType); + loadExpression(lhs, safeConvertBounds, baseAlreadyOnStack); + method.convert(operandBounds.within(method.peekType())); + loadExpression(rhs, safeConvertBounds, false); + method.convert(operandBounds.within(method.peekType())); + } else { + // Can reorder and move conversion into the operand. Combine load and convert into single operations. + loadExpression(lhs, operandBounds, baseAlreadyOnStack); + loadExpression(rhs, operandBounds, false); + } } else { // Can't reorder. Load and convert separately. - load(lhs, lhs.getType(), baseAlreadyOnStack); - load(rhs, rhs.getType(), false); - method.swap().convert(type).swap().convert(type); + final TypeBounds safeConvertBounds = TypeBounds.UNBOUNDED.notNarrowerThan(narrowestOperandType); + loadExpression(lhs, safeConvertBounds, baseAlreadyOnStack); + final Type lhsLoadedType = method.peekType(); + loadExpression(rhs, safeConvertBounds, false); + final Type convertedLhsType = operandBounds.within(method.peekType()); + if (convertedLhsType != lhsLoadedType) { + // Do it conditionally, so that if conversion is a no-op we don't introduce a SWAP, SWAP. + method.swap().convert(convertedLhsType).swap(); + } + method.convert(operandBounds.within(method.peekType())); } + assert Type.generic(method.peekType()) == operandBounds.narrowest; + assert Type.generic(method.peekType(1)) == operandBounds.narrowest; return method; } - MethodEmitter loadBinaryOperands(final BinaryNode node) { - return loadBinaryOperands(node.lhs(), node.rhs(), node.getType(), false); + private static final Type undefinedToNumber(final Type type) { + return type == Type.UNDEFINED ? Type.NUMBER : type; } - MethodEmitter load(final Expression node, final Type type) { - return load(node, type, false); + private static final class TypeBounds { + final Type narrowest; + final Type widest; + + static final TypeBounds UNBOUNDED = new TypeBounds(Type.UNKNOWN, Type.OBJECT); + static final TypeBounds INT = exact(Type.INT); + static final TypeBounds OBJECT = exact(Type.OBJECT); + static final TypeBounds BOOLEAN = exact(Type.BOOLEAN); + + static TypeBounds exact(final Type type) { + return new TypeBounds(type, type); + } + + TypeBounds(final Type narrowest, final Type widest) { + assert widest != null && widest != Type.UNDEFINED && widest != Type.UNKNOWN : widest; + assert narrowest != null && narrowest != Type.UNDEFINED : narrowest; + assert !narrowest.widerThan(widest) : narrowest + " wider than " + widest; + assert !widest.narrowerThan(narrowest); + this.narrowest = Type.generic(narrowest); + this.widest = Type.generic(widest); + } + + TypeBounds notNarrowerThan(final Type type) { + return maybeNew(Type.narrowest(Type.widest(narrowest, type), widest), widest); + } + + TypeBounds notWiderThan(final Type type) { + return maybeNew(Type.narrowest(narrowest, type), Type.narrowest(widest, type)); + } + + boolean canBeNarrowerThan(final Type type) { + return narrowest.narrowerThan(type); + } + + TypeBounds maybeNew(final Type newNarrowest, final Type newWidest) { + if(newNarrowest == narrowest && newWidest == widest) { + return this; + } + return new TypeBounds(newNarrowest, newWidest); + } + + TypeBounds booleanToInt() { + return maybeNew(CodeGenerator.booleanToInt(narrowest), CodeGenerator.booleanToInt(widest)); + } + + TypeBounds objectToNumber() { + return maybeNew(CodeGenerator.objectToNumber(narrowest), CodeGenerator.objectToNumber(widest)); + } + + Type within(final Type type) { + if(type.narrowerThan(narrowest)) { + return narrowest; + } + if(type.widerThan(widest)) { + return widest; + } + return type; + } + + @Override + public String toString() { + return "[" + narrowest + ", " + widest + "]"; + } } - private MethodEmitter load(final Expression node, final Type type, final boolean baseAlreadyOnStack) { - final Symbol symbol = node.getSymbol(); + private static Type booleanToInt(final Type t) { + return t == Type.BOOLEAN ? Type.INT : t; + } - // If we lack symbols, we just generate what we see. - if (symbol == null || type == null) { - node.accept(this); - return method; + private static Type objectToNumber(final Type t) { + return t.isObject() ? Type.NUMBER : t; + } + + MethodEmitter loadExpressionAsType(final Expression expr, final Type type) { + if(type == Type.BOOLEAN) { + return loadExpressionAsBoolean(expr); + } else if(type == Type.UNDEFINED) { + assert expr.getType() == Type.UNDEFINED; + return loadExpressionAsObject(expr); } + // having no upper bound preserves semantics of optimistic operations in the expression (by not having them + // converted early) and then applies explicit conversion afterwards. + return loadExpression(expr, TypeBounds.UNBOUNDED.notNarrowerThan(type)).convert(type); + } + + private MethodEmitter loadExpression(final Expression expr, final TypeBounds resultBounds) { + return loadExpression(expr, resultBounds, false); + } - assert !type.isUnknown(); + /** + * Emits code for evaluating an expression and leaving its value on top of the stack, narrowing or widening it if + * necessary. + * @param expr the expression to load + * @param resultBounds the incoming type bounds. The value on the top of the stack is guaranteed to not be of narrower + * type than the narrowest bound, or wider type than the widest bound after it is loaded. + * @param baseAlreadyOnStack true if the base of an access or index node is already on the stack. Used to avoid + * double evaluation of bases in self-assignment expressions to access and index nodes. {@code Type.OBJECT} is used + * to indicate the widest possible type. + * @return the method emitter + */ + private MethodEmitter loadExpression(final Expression expr, final TypeBounds resultBounds, final boolean baseAlreadyOnStack) { /* * The load may be of type IdentNode, e.g. "x", AccessNode, e.g. "x.y" @@ -421,35 +724,54 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex */ final CodeGenerator codegen = this; - node.accept(new NodeVisitor<LexicalContext>(lc) { + final Node currentDiscard = codegen.lc.getCurrentDiscard(); + expr.accept(new NodeOperatorVisitor<LexicalContext>(new LexicalContext()) { @Override public boolean enterIdentNode(final IdentNode identNode) { - loadIdent(identNode, type); + loadIdent(identNode, resultBounds); return false; } @Override public boolean enterAccessNode(final AccessNode accessNode) { - if (!baseAlreadyOnStack) { - load(accessNode.getBase(), Type.OBJECT); - } - assert method.peekType().isObject(); - method.dynamicGet(type, accessNode.getProperty().getName(), getCallSiteFlags(), accessNode.isFunction()); + new OptimisticOperation(accessNode, resultBounds) { + @Override + void loadStack() { + if (!baseAlreadyOnStack) { + loadExpressionAsObject(accessNode.getBase()); + } + assert method.peekType().isObject(); + } + @Override + void consumeStack() { + final int flags = getCallSiteFlags(); + dynamicGet(accessNode.getProperty(), flags, accessNode.isFunction(), accessNode.isIndex()); + } + }.emit(baseAlreadyOnStack ? 1 : 0); return false; } @Override public boolean enterIndexNode(final IndexNode indexNode) { - if (!baseAlreadyOnStack) { - load(indexNode.getBase(), Type.OBJECT); - load(indexNode.getIndex()); - } - method.dynamicGetIndex(type, getCallSiteFlags(), indexNode.isFunction()); + new OptimisticOperation(indexNode, resultBounds) { + @Override + void loadStack() { + if (!baseAlreadyOnStack) { + loadExpressionAsObject(indexNode.getBase()); + loadExpressionUnbounded(indexNode.getIndex()); + } + } + @Override + void consumeStack() { + final int flags = getCallSiteFlags(); + dynamicGetIndex(flags, indexNode.isFunction()); + } + }.emit(baseAlreadyOnStack ? 2 : 0); return false; } @Override - public boolean enterFunctionNode(FunctionNode functionNode) { + public boolean enterFunctionNode(final FunctionNode functionNode) { // function nodes will always leave a constructed function object on stack, no need to load the symbol // separately as in enterDefault() lc.pop(functionNode); @@ -459,204 +781,496 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex // is the last element in the compilation pipeline, the AST it produces is not used externally. So, we // re-push the original functionNode. lc.push(functionNode); - method.convert(type); return false; } @Override - public boolean enterCallNode(CallNode callNode) { - return codegen.enterCallNode(callNode, type); + public boolean enterASSIGN(final BinaryNode binaryNode) { + loadASSIGN(binaryNode); + return false; } @Override - public boolean enterLiteralNode(LiteralNode<?> literalNode) { - return codegen.enterLiteralNode(literalNode, type); + public boolean enterASSIGN_ADD(final BinaryNode binaryNode) { + loadASSIGN_ADD(binaryNode); + return false; } @Override - public boolean enterDefault(final Node otherNode) { - final Node currentDiscard = codegen.lc.getCurrentDiscard(); - otherNode.accept(codegen); // generate code for whatever we are looking at. - if(currentDiscard != otherNode) { - method.load(symbol); // load the final symbol to the stack (or nop if no slot, then result is already there) - assert method.peekType() != null; - method.convert(type); - } + public boolean enterASSIGN_BIT_AND(final BinaryNode binaryNode) { + loadASSIGN_BIT_AND(binaryNode); return false; } - }); - return method; - } + @Override + public boolean enterASSIGN_BIT_OR(final BinaryNode binaryNode) { + loadASSIGN_BIT_OR(binaryNode); + return false; + } - @Override - public boolean enterAccessNode(final AccessNode accessNode) { - load(accessNode); - return false; - } + @Override + public boolean enterASSIGN_BIT_XOR(final BinaryNode binaryNode) { + loadASSIGN_BIT_XOR(binaryNode); + return false; + } - /** - * Initialize a specific set of vars to undefined. This has to be done at - * the start of each method for local variables that aren't passed as - * parameters. - * - * @param symbols list of symbols. - */ - private void initSymbols(final Iterable<Symbol> symbols) { - final LinkedList<Symbol> numbers = new LinkedList<>(); - final LinkedList<Symbol> objects = new LinkedList<>(); + @Override + public boolean enterASSIGN_DIV(final BinaryNode binaryNode) { + loadASSIGN_DIV(binaryNode); + return false; + } - for (final Symbol symbol : symbols) { - /* - * The following symbols are guaranteed to be defined and thus safe - * from having undefined written to them: parameters internals this - * - * Otherwise we must, unless we perform control/escape analysis, - * assign them undefined. - */ - final boolean isInternal = symbol.isParam() || symbol.isInternal() || symbol.isThis() || !symbol.canBeUndefined(); - - if (symbol.hasSlot() && !isInternal) { - assert symbol.getSymbolType().isNumber() || symbol.getSymbolType().isObject() : "no potentially undefined narrower local vars than doubles are allowed: " + symbol + " in " + lc.getCurrentFunction(); - if (symbol.getSymbolType().isNumber()) { - numbers.add(symbol); - } else if (symbol.getSymbolType().isObject()) { - objects.add(symbol); - } + @Override + public boolean enterASSIGN_MOD(final BinaryNode binaryNode) { + loadASSIGN_MOD(binaryNode); + return false; } - } - initSymbols(numbers, Type.NUMBER); - initSymbols(objects, Type.OBJECT); - } + @Override + public boolean enterASSIGN_MUL(final BinaryNode binaryNode) { + loadASSIGN_MUL(binaryNode); + return false; + } - private void initSymbols(final LinkedList<Symbol> symbols, final Type type) { - final Iterator<Symbol> it = symbols.iterator(); - if(it.hasNext()) { - method.loadUndefined(type); - boolean hasNext; - do { - final Symbol symbol = it.next(); - hasNext = it.hasNext(); - if(hasNext) { - method.dup(); - } - method.store(symbol); - } while(hasNext); + @Override + public boolean enterASSIGN_SAR(final BinaryNode binaryNode) { + loadASSIGN_SAR(binaryNode); + return false; + } + + @Override + public boolean enterASSIGN_SHL(final BinaryNode binaryNode) { + loadASSIGN_SHL(binaryNode); + return false; + } + + @Override + public boolean enterASSIGN_SHR(final BinaryNode binaryNode) { + loadASSIGN_SHR(binaryNode); + return false; + } + + @Override + public boolean enterASSIGN_SUB(final BinaryNode binaryNode) { + loadASSIGN_SUB(binaryNode); + return false; + } + + @Override + public boolean enterCallNode(final CallNode callNode) { + return loadCallNode(callNode, resultBounds); + } + + @Override + public boolean enterLiteralNode(final LiteralNode<?> literalNode) { + loadLiteral(literalNode, resultBounds); + return false; + } + + @Override + public boolean enterTernaryNode(final TernaryNode ternaryNode) { + loadTernaryNode(ternaryNode, resultBounds); + return false; + } + + @Override + public boolean enterADD(final BinaryNode binaryNode) { + loadADD(binaryNode, resultBounds); + return false; + } + + @Override + public boolean enterSUB(final UnaryNode unaryNode) { + loadSUB(unaryNode, resultBounds); + return false; + } + + @Override + public boolean enterSUB(final BinaryNode binaryNode) { + loadSUB(binaryNode, resultBounds); + return false; + } + + @Override + public boolean enterMUL(final BinaryNode binaryNode) { + loadMUL(binaryNode, resultBounds); + return false; + } + + @Override + public boolean enterDIV(final BinaryNode binaryNode) { + loadDIV(binaryNode, resultBounds); + return false; + } + + @Override + public boolean enterMOD(final BinaryNode binaryNode) { + loadMOD(binaryNode, resultBounds); + return false; + } + + @Override + public boolean enterSAR(final BinaryNode binaryNode) { + loadSAR(binaryNode); + return false; + } + + @Override + public boolean enterSHL(final BinaryNode binaryNode) { + loadSHL(binaryNode); + return false; + } + + @Override + public boolean enterSHR(final BinaryNode binaryNode) { + loadSHR(binaryNode); + return false; + } + + @Override + public boolean enterCOMMALEFT(final BinaryNode binaryNode) { + loadCOMMALEFT(binaryNode, resultBounds); + return false; + } + + @Override + public boolean enterCOMMARIGHT(final BinaryNode binaryNode) { + loadCOMMARIGHT(binaryNode, resultBounds); + return false; + } + + @Override + public boolean enterAND(final BinaryNode binaryNode) { + loadAND_OR(binaryNode, resultBounds, true); + return false; + } + + @Override + public boolean enterOR(final BinaryNode binaryNode) { + loadAND_OR(binaryNode, resultBounds, false); + return false; + } + + @Override + public boolean enterNOT(final UnaryNode unaryNode) { + loadNOT(unaryNode); + return false; + } + + @Override + public boolean enterADD(final UnaryNode unaryNode) { + loadADD(unaryNode, resultBounds); + return false; + } + + @Override + public boolean enterBIT_NOT(final UnaryNode unaryNode) { + loadBIT_NOT(unaryNode); + return false; + } + + @Override + public boolean enterBIT_AND(final BinaryNode binaryNode) { + loadBIT_AND(binaryNode); + return false; + } + + @Override + public boolean enterBIT_OR(final BinaryNode binaryNode) { + loadBIT_OR(binaryNode); + return false; + } + + @Override + public boolean enterBIT_XOR(final BinaryNode binaryNode) { + loadBIT_XOR(binaryNode); + return false; + } + + @Override + public boolean enterVOID(final UnaryNode unaryNode) { + loadVOID(unaryNode, resultBounds); + return false; + } + + @Override + public boolean enterEQ(final BinaryNode binaryNode) { + loadCmp(binaryNode, Condition.EQ); + return false; + } + + @Override + public boolean enterEQ_STRICT(final BinaryNode binaryNode) { + loadCmp(binaryNode, Condition.EQ); + return false; + } + + @Override + public boolean enterGE(final BinaryNode binaryNode) { + loadCmp(binaryNode, Condition.GE); + return false; + } + + @Override + public boolean enterGT(final BinaryNode binaryNode) { + loadCmp(binaryNode, Condition.GT); + return false; + } + + @Override + public boolean enterLE(final BinaryNode binaryNode) { + loadCmp(binaryNode, Condition.LE); + return false; + } + + @Override + public boolean enterLT(final BinaryNode binaryNode) { + loadCmp(binaryNode, Condition.LT); + return false; + } + + @Override + public boolean enterNE(final BinaryNode binaryNode) { + loadCmp(binaryNode, Condition.NE); + return false; + } + + @Override + public boolean enterNE_STRICT(final BinaryNode binaryNode) { + loadCmp(binaryNode, Condition.NE); + return false; + } + + @Override + public boolean enterObjectNode(final ObjectNode objectNode) { + loadObjectNode(objectNode); + return false; + } + + @Override + public boolean enterRuntimeNode(final RuntimeNode runtimeNode) { + loadRuntimeNode(runtimeNode); + return false; + } + + @Override + public boolean enterNEW(final UnaryNode unaryNode) { + loadNEW(unaryNode); + return false; + } + + @Override + public boolean enterDECINC(final UnaryNode unaryNode) { + loadDECINC(unaryNode); + return false; + } + + @Override + public boolean enterJoinPredecessorExpression(final JoinPredecessorExpression joinExpr) { + loadExpression(joinExpr.getExpression(), resultBounds); + return false; + } + + @Override + public boolean enterGetSplitState(final GetSplitState getSplitState) { + method.loadScope(); + method.invoke(Scope.GET_SPLIT_STATE); + return false; + } + + @Override + public boolean enterDefault(final Node otherNode) { + // Must have handled all expressions that can legally be encountered. + throw new AssertionError(otherNode.getClass().getName()); + } + }); + if(currentDiscard != expr) { + coerceStackTop(resultBounds); } + return method; + } + + private MethodEmitter coerceStackTop(final TypeBounds typeBounds) { + return method.convert(typeBounds.within(method.peekType())); } /** - * Create symbol debug information. + * Closes any still open entries for this block's local variables in the bytecode local variable table. * * @param block block containing symbols. */ - private void symbolInfo(final Block block) { + private void closeBlockVariables(final Block block) { for (final Symbol symbol : block.getSymbols()) { - if (symbol.hasSlot()) { - method.localVariable(symbol, block.getEntryLabel(), block.getBreakLabel()); + if (symbol.isBytecodeLocal()) { + method.closeLocalVariable(symbol, block.getBreakLabel()); } } } @Override public boolean enterBlock(final Block block) { + method.label(block.getEntryLabel()); + if(!method.isReachable()) { + return false; + } if(lc.isFunctionBody() && emittedMethods.contains(lc.getCurrentFunction().getName())) { return false; } - method.label(block.getEntryLabel()); initLocals(block); + assert lc.getUsedSlotCount() == method.getFirstTemp(); return true; } + private boolean useOptimisticTypes() { + return !lc.inSplitNode() && compiler.useOptimisticTypes(); + } + @Override public Node leaveBlock(final Block block) { - method.label(block.getBreakLabel()); - symbolInfo(block); + popBlockScope(block); + method.beforeJoinPoint(block); + + closeBlockVariables(block); + lc.releaseSlots(); + assert !method.isReachable() || (lc.isFunctionBody() ? 0 : lc.getUsedSlotCount()) == method.getFirstTemp() : + "reachable="+method.isReachable() + + " isFunctionBody=" + lc.isFunctionBody() + + " usedSlotCount=" + lc.getUsedSlotCount() + + " firstTemp=" + method.getFirstTemp(); - if (block.needsScope() && !block.isTerminal()) { - popBlockScope(block); - } return block; } private void popBlockScope(final Block block) { - final Label exitLabel = new Label("block_exit"); - final Label recoveryLabel = new Label("block_catch"); - final Label skipLabel = new Label("skip_catch"); + final Label breakLabel = block.getBreakLabel(); - /* pop scope a la try-finally */ - method.loadCompilerConstant(SCOPE); - method.invoke(ScriptObject.GET_PROTO); - method.storeCompilerConstant(SCOPE); - method._goto(skipLabel); - method.label(exitLabel); + if(!block.needsScope() || lc.isFunctionBody()) { + emitBlockBreakLabel(breakLabel); + return; + } + + final Label beginTryLabel = scopeEntryLabels.pop(); + final Label recoveryLabel = new Label("block_popscope_catch"); + emitBlockBreakLabel(breakLabel); + final boolean bodyCanThrow = breakLabel.isAfter(beginTryLabel); + if(bodyCanThrow) { + method._try(beginTryLabel, breakLabel, recoveryLabel); + } + + Label afterCatchLabel = null; + + if(method.isReachable()) { + popScope(); + if(bodyCanThrow) { + afterCatchLabel = new Label("block_after_catch"); + method._goto(afterCatchLabel); + } + } + + if(bodyCanThrow) { + assert !method.isReachable(); + method._catch(recoveryLabel); + popScopeException(); + method.athrow(); + } + if(afterCatchLabel != null) { + method.label(afterCatchLabel); + } + } + + private void emitBlockBreakLabel(final Label breakLabel) { + // TODO: this is totally backwards. Block should not be breakable, LabelNode should be breakable. + final LabelNode labelNode = lc.getCurrentBlockLabelNode(); + if(labelNode != null) { + // Only have conversions if we're reachable + assert labelNode.getLocalVariableConversion() == null || method.isReachable(); + method.beforeJoinPoint(labelNode); + method.breakLabel(breakLabel, labeledBlockBreakLiveLocals.pop()); + } else { + method.label(breakLabel); + } + } + + private void popScope() { + popScopes(1); + } + + /** + * Pop scope as part of an exception handler. Similar to {@code popScope()} but also takes care of adjusting the + * number of scopes that needs to be popped in case a rest-of continuation handler encounters an exception while + * performing a ToPrimitive conversion. + */ + private void popScopeException() { + popScope(); + final ContinuationInfo ci = getContinuationInfo(); + if(ci != null) { + final Label catchLabel = ci.catchLabel; + if(catchLabel != METHOD_BOUNDARY && catchLabel == catchLabels.peek()) { + ++ci.exceptionScopePops; + } + } + } - method._catch(recoveryLabel); + private void popScopesUntil(final LexicalContextNode until) { + popScopes(lc.getScopeNestingLevelTo(until)); + } + + private void popScopes(final int count) { + if(count == 0) { + return; + } + assert count > 0; // together with count == 0 check, asserts nonnegative count + if (!method.hasScope()) { + // We can sometimes invoke this method even if the method has no slot for the scope object. Typical example: + // for(;;) { with({}) { break; } }. WithNode normally creates a scope, but if it uses no identifiers and + // nothing else forces creation of a scope in the method, we just won't have the :scope local variable. + return; + } method.loadCompilerConstant(SCOPE); - method.invoke(ScriptObject.GET_PROTO); + for(int i = 0; i < count; ++i) { + method.invoke(ScriptObject.GET_PROTO); + } method.storeCompilerConstant(SCOPE); - method.athrow(); - method.label(skipLabel); - method._try(block.getEntryLabel(), exitLabel, recoveryLabel, Throwable.class); } @Override public boolean enterBreakNode(final BreakNode breakNode) { - lineNumber(breakNode); + return enterJumpStatement(breakNode); + } - final BreakableNode breakFrom = lc.getBreakable(breakNode.getLabel()); - for (int i = 0; i < lc.getScopeNestingLevelTo(breakFrom); i++) { - closeWith(); + private boolean enterJumpStatement(final JumpStatement jump) { + if(!method.isReachable()) { + return false; } - method.splitAwareGoto(lc, breakFrom.getBreakLabel()); + enterStatement(jump); + + method.beforeJoinPoint(jump); + final BreakableNode target = jump.getTarget(lc); + popScopesUntil(target); + final Label targetLabel = jump.getTargetLabel(target); + targetLabel.markAsBreakTarget(); + method._goto(targetLabel); return false; } private int loadArgs(final List<Expression> args) { - return loadArgs(args, null, false, args.size()); - } - - private int loadArgs(final List<Expression> args, final String signature, final boolean isVarArg, final int argCount) { + final int argCount = args.size(); // arg have already been converted to objects here. - if (isVarArg || argCount > LinkerCallSite.ARGLIMIT) { + if (argCount > LinkerCallSite.ARGLIMIT) { loadArgsArray(args); return 1; } - // pad with undefined if size is too short. argCount is the real number of args - int n = 0; - final Type[] params = signature == null ? null : Type.getMethodArguments(signature); for (final Expression arg : args) { assert arg != null; - if (n >= argCount) { - load(arg); - method.pop(); // we had to load the arg for its side effects - } else if (params != null) { - load(arg, params[n]); - } else { - load(arg); - } - n++; + loadExpressionUnbounded(arg); } - - while (n < argCount) { - method.loadUndefined(Type.OBJECT); - n++; - } - return argCount; } - - @Override - public boolean enterCallNode(final CallNode callNode) { - return enterCallNode(callNode, callNode.getType()); - } - - private boolean enterCallNode(final CallNode callNode, final Type callNodeType) { + private boolean loadCallNode(final CallNode callNode, final TypeBounds resultBounds) { lineNumber(callNode.getLineNumber()); final List<Expression> args = callNode.getArgs(); @@ -668,68 +1282,122 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex private MethodEmitter sharedScopeCall(final IdentNode identNode, final int flags) { final Symbol symbol = identNode.getSymbol(); - int scopeCallFlags = flags; - method.loadCompilerConstant(SCOPE); - if (isFastScope(symbol)) { - method.load(getScopeProtoDepth(currentBlock, symbol)); - scopeCallFlags |= CALLSITE_FAST_SCOPE; - } else { - method.load(-1); // Bypass fast-scope code in shared callsite - } - loadArgs(args); - final Type[] paramTypes = method.getTypesFromStack(args.size()); - final SharedScopeCall scopeCall = codegenLexicalContext.getScopeCall(unit, symbol, identNode.getType(), callNodeType, paramTypes, scopeCallFlags); - return scopeCall.generateInvoke(method); + final boolean isFastScope = isFastScope(symbol); + final int scopeCallFlags = flags | (isFastScope ? CALLSITE_FAST_SCOPE : 0); + new OptimisticOperation(callNode, resultBounds) { + @Override + void loadStack() { + method.loadCompilerConstant(SCOPE); + if (isFastScope) { + method.load(getScopeProtoDepth(currentBlock, symbol)); + } else { + method.load(-1); // Bypass fast-scope code in shared callsite + } + loadArgs(args); + } + @Override + void consumeStack() { + final Type[] paramTypes = method.getTypesFromStack(args.size()); + // We have trouble finding e.g. in Type.typeFor(asm.Type) because it can't see the Context class + // loader, so we need to weaken reference signatures to Object. + for(int i = 0; i < paramTypes.length; ++i) { + paramTypes[i] = Type.generic(paramTypes[i]); + } + // As shared scope calls are only used in non-optimistic compilation, we switch from using + // TypeBounds to just a single definitive type, resultBounds.widest. + final SharedScopeCall scopeCall = codegenLexicalContext.getScopeCall(unit, symbol, + identNode.getType(), resultBounds.widest, paramTypes, scopeCallFlags); + scopeCall.generateInvoke(method); + } + }.emit(); + return method; } - private void scopeCall(final IdentNode node, final int flags) { - load(node, Type.OBJECT); // Type.OBJECT as foo() makes no sense if foo == 3 - // ScriptFunction will see CALLSITE_SCOPE and will bind scope accordingly. - method.loadUndefined(Type.OBJECT); //the 'this' object - method.dynamicCall(callNodeType, 2 + loadArgs(args), flags); + private void scopeCall(final IdentNode ident, final int flags) { + new OptimisticOperation(callNode, resultBounds) { + int argsCount; + @Override + void loadStack() { + loadExpressionAsObject(ident); // foo() makes no sense if foo == 3 + // ScriptFunction will see CALLSITE_SCOPE and will bind scope accordingly. + method.loadUndefined(Type.OBJECT); //the 'this' + argsCount = loadArgs(args); + } + @Override + void consumeStack() { + dynamicCall(2 + argsCount, flags); + } + }.emit(); } - private void evalCall(final IdentNode node, final int flags) { - load(node, Type.OBJECT); // Type.OBJECT as foo() makes no sense if foo == 3 - - final Label not_eval = new Label("not_eval"); + private void evalCall(final IdentNode ident, final int flags) { + final Label invoke_direct_eval = new Label("invoke_direct_eval"); + final Label is_not_eval = new Label("is_not_eval"); final Label eval_done = new Label("eval_done"); - // check if this is the real built-in eval - method.dup(); - globalIsEval(); - - method.ifeq(not_eval); - // We don't need ScriptFunction object for 'eval' - method.pop(); - - method.loadCompilerConstant(SCOPE); // Load up self (scope). - - final CallNode.EvalArgs evalArgs = callNode.getEvalArgs(); - // load evaluated code - load(evalArgs.getCode(), Type.OBJECT); - // load second and subsequent args for side-effect - final List<Expression> args = callNode.getArgs(); - final int numArgs = args.size(); - for (int i = 1; i < numArgs; i++) { - load(args.get(i)).pop(); - } - // special/extra 'eval' arguments - load(evalArgs.getThis()); - method.load(evalArgs.getLocation()); - method.load(evalArgs.getStrictMode()); - method.convert(Type.OBJECT); - - // direct call to Global.directEval - globalDirectEval(); - method.convert(callNodeType); - method._goto(eval_done); + new OptimisticOperation(callNode, resultBounds) { + int argsCount; + @Override + void loadStack() { + /** + * We want to load 'eval' to check if it is indeed global builtin eval. + * If this eval call is inside a 'with' statement, dyn:getMethod|getProp|getElem + * would be generated if ident is a "isFunction". But, that would result in a + * bound function from WithObject. We don't want that as bound function as that + * won't be detected as builtin eval. So, we make ident as "not a function" which + * results in "dyn:getProp|getElem|getMethod" being generated and so WithObject + * would return unbounded eval function. + * + * Example: + * + * var global = this; + * function func() { + * with({ eval: global.eval) { eval("var x = 10;") } + * } + */ + loadExpressionAsObject(ident.setIsNotFunction()); // Type.OBJECT as foo() makes no sense if foo == 3 + globalIsEval(); + method.ifeq(is_not_eval); + + // Load up self (scope). + method.loadCompilerConstant(SCOPE); + final List<Expression> evalArgs = callNode.getEvalArgs().getArgs(); + // load evaluated code + loadExpressionAsObject(evalArgs.get(0)); + // load second and subsequent args for side-effect + final int numArgs = evalArgs.size(); + for (int i = 1; i < numArgs; i++) { + loadAndDiscard(evalArgs.get(i)); + } + method._goto(invoke_direct_eval); + + method.label(is_not_eval); + // load this time but with dyn:getMethod|getProp|getElem + loadExpressionAsObject(ident); // Type.OBJECT as foo() makes no sense if foo == 3 + // This is some scope 'eval' or global eval replaced by user + // but not the built-in ECMAScript 'eval' function call + method.loadNull(); + argsCount = loadArgs(callNode.getArgs()); + } - method.label(not_eval); - // This is some scope 'eval' or global eval replaced by user - // but not the built-in ECMAScript 'eval' function call - method.loadNull(); - method.dynamicCall(callNodeType, 2 + loadArgs(args), flags); + @Override + void consumeStack() { + // Ordinary call + dynamicCall(2 + argsCount, flags); + method._goto(eval_done); + + method.label(invoke_direct_eval); + // Special/extra 'eval' arguments. These can be loaded late (in consumeStack) as we know none of + // them can ever be optimistic. + method.loadCompilerConstant(THIS); + method.load(callNode.getEvalArgs().getLocation()); + method.load(CodeGenerator.this.lc.getCurrentFunction().isStrict()); + // direct call to Global.directEval + globalDirectEval(); + convertOptimisticReturnValue(); + coerceStackTop(resultBounds); + } + }.emit(); method.label(eval_done); } @@ -748,13 +1416,14 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex if (callNode.isEval()) { evalCall(node, flags); } else if (useCount <= SharedScopeCall.FAST_SCOPE_CALL_THRESHOLD - || (!isFastScope(symbol) && useCount <= SharedScopeCall.SLOW_SCOPE_CALL_THRESHOLD) - || CodeGenerator.this.lc.inDynamicScope()) { + || !isFastScope(symbol) && useCount <= SharedScopeCall.SLOW_SCOPE_CALL_THRESHOLD + || CodeGenerator.this.lc.inDynamicScope() + || isOptimisticOrRestOf()) { scopeCall(node, flags); } else { sharedScopeCall(node, flags); } - assert method.peekType().equals(callNodeType) : method.peekType() + "!=" + callNode.getType(); + assert method.peekType().equals(resultBounds.within(callNode.getType())) : method.peekType() + " != " + resultBounds + "(" + callNode.getType() + ")"; } else { enterDefault(node); } @@ -764,104 +1433,158 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex @Override public boolean enterAccessNode(final AccessNode node) { - load(node.getBase(), Type.OBJECT); - method.dup(); - method.dynamicGet(node.getType(), node.getProperty().getName(), getCallSiteFlags(), true); - method.swap(); - method.dynamicCall(callNodeType, 2 + loadArgs(args), getCallSiteFlags()); + //check if this is an apply to call node. only real applies, that haven't been + //shadowed from their way to the global scope counts + + //call nodes have program points. + + final int flags = getCallSiteFlags() | (callNode.isApplyToCall() ? CALLSITE_APPLY_TO_CALL : 0); + + new OptimisticOperation(callNode, resultBounds) { + int argCount; + @Override + void loadStack() { + loadExpressionAsObject(node.getBase()); + method.dup(); + // NOTE: not using a nested OptimisticOperation on this dynamicGet, as we expect to get back + // a callable object. Nobody in their right mind would optimistically type this call site. + assert !node.isOptimistic(); + method.dynamicGet(node.getType(), node.getProperty(), flags, true, node.isIndex()); + method.swap(); + argCount = loadArgs(args); + } + @Override + void consumeStack() { + dynamicCall(2 + argCount, flags); + } + }.emit(); return false; } @Override public boolean enterFunctionNode(final FunctionNode origCallee) { - // NOTE: visiting the callee will leave a constructed ScriptFunction object on the stack if - // callee.needsCallee() == true - final FunctionNode callee = (FunctionNode)origCallee.accept(CodeGenerator.this); - - final boolean isVarArg = callee.isVarArg(); - final int argCount = isVarArg ? -1 : callee.getParameters().size(); - - final String signature = new FunctionSignature(true, callee.needsCallee(), callee.getReturnType(), isVarArg ? null : callee.getParameters()).toString(); + new OptimisticOperation(callNode, resultBounds) { + FunctionNode callee; + int argsCount; + @Override + void loadStack() { + callee = (FunctionNode)origCallee.accept(CodeGenerator.this); + if (callee.isStrict()) { // "this" is undefined + method.loadUndefined(Type.OBJECT); + } else { // get global from scope (which is the self) + globalInstance(); + } + argsCount = loadArgs(args); + } - if (callee.isStrict()) { // self is undefined - method.loadUndefined(Type.OBJECT); - } else { // get global from scope (which is the self) - globalInstance(); - } - loadArgs(args, signature, isVarArg, argCount); - assert callee.getCompileUnit() != null : "no compile unit for " + callee.getName() + " " + Debug.id(callee) + " " + callNode; - method.invokestatic(callee.getCompileUnit().getUnitClassName(), callee.getName(), signature); - assert method.peekType().equals(callee.getReturnType()) : method.peekType() + " != " + callee.getReturnType(); - method.convert(callNodeType); + @Override + void consumeStack() { + final int flags = getCallSiteFlags(); + //assert callNodeType.equals(callee.getReturnType()) : callNodeType + " != " + callee.getReturnType(); + dynamicCall(2 + argsCount, flags); + } + }.emit(); return false; } @Override public boolean enterIndexNode(final IndexNode node) { - load(node.getBase(), Type.OBJECT); - method.dup(); - final Type indexType = node.getIndex().getType(); - if (indexType.isObject() || indexType.isBoolean()) { - load(node.getIndex(), Type.OBJECT); //TODO - } else { - load(node.getIndex()); - } - method.dynamicGetIndex(node.getType(), getCallSiteFlags(), true); - method.swap(); - method.dynamicCall(callNodeType, 2 + loadArgs(args), getCallSiteFlags()); - + new OptimisticOperation(callNode, resultBounds) { + int argsCount; + @Override + void loadStack() { + loadExpressionAsObject(node.getBase()); + method.dup(); + final Type indexType = node.getIndex().getType(); + if (indexType.isObject() || indexType.isBoolean()) { + loadExpressionAsObject(node.getIndex()); //TODO boolean + } else { + loadExpressionUnbounded(node.getIndex()); + } + // NOTE: not using a nested OptimisticOperation on this dynamicGetIndex, as we expect to get + // back a callable object. Nobody in their right mind would optimistically type this call site. + assert !node.isOptimistic(); + method.dynamicGetIndex(node.getType(), getCallSiteFlags(), true); + method.swap(); + argsCount = loadArgs(args); + } + @Override + void consumeStack() { + final int flags = getCallSiteFlags(); + dynamicCall(2 + argsCount, flags); + } + }.emit(); return false; } @Override protected boolean enterDefault(final Node node) { - // Load up function. - load(function, Type.OBJECT); //TODO, e.g. booleans can be used as functions - method.loadUndefined(Type.OBJECT); // ScriptFunction will figure out the correct this when it sees CALLSITE_SCOPE - method.dynamicCall(callNodeType, 2 + loadArgs(args), getCallSiteFlags() | CALLSITE_SCOPE); - + new OptimisticOperation(callNode, resultBounds) { + int argsCount; + @Override + void loadStack() { + // Load up function. + loadExpressionAsObject(function); //TODO, e.g. booleans can be used as functions + method.loadUndefined(Type.OBJECT); // ScriptFunction will figure out the correct this when it sees CALLSITE_SCOPE + argsCount = loadArgs(args); + } + @Override + void consumeStack() { + final int flags = getCallSiteFlags() | CALLSITE_SCOPE; + dynamicCall(2 + argsCount, flags); + } + }.emit(); return false; } }); - method.store(callNode.getSymbol()); - return false; } + /** + * Returns the flags with optimistic flag and program point removed. + * @param flags the flags that need optimism stripped from them. + * @return flags without optimism + */ + static int nonOptimisticFlags(final int flags) { + return flags & ~(CALLSITE_OPTIMISTIC | -1 << CALLSITE_PROGRAM_POINT_SHIFT); + } + @Override public boolean enterContinueNode(final ContinueNode continueNode) { - lineNumber(continueNode); - - final LoopNode continueTo = lc.getContinueTo(continueNode.getLabel()); - for (int i = 0; i < lc.getScopeNestingLevelTo(continueTo); i++) { - closeWith(); - } - method.splitAwareGoto(lc, continueTo.getContinueLabel()); - - return false; + return enterJumpStatement(continueNode); } @Override public boolean enterEmptyNode(final EmptyNode emptyNode) { - lineNumber(emptyNode); + if(!method.isReachable()) { + return false; + } + enterStatement(emptyNode); return false; } @Override public boolean enterExpressionStatement(final ExpressionStatement expressionStatement) { - lineNumber(expressionStatement); + if(!method.isReachable()) { + return false; + } + enterStatement(expressionStatement); - expressionStatement.getExpression().accept(this); + loadAndDiscard(expressionStatement.getExpression()); + assert method.getStackSize() == 0; return false; } @Override public boolean enterBlockStatement(final BlockStatement blockStatement) { - lineNumber(blockStatement); + if(!method.isReachable()) { + return false; + } + enterStatement(blockStatement); blockStatement.getBlock().accept(this); @@ -870,83 +1593,79 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex @Override public boolean enterForNode(final ForNode forNode) { - lineNumber(forNode); - + if(!method.isReachable()) { + return false; + } + enterStatement(forNode); if (forNode.isForIn()) { enterForIn(forNode); } else { - enterFor(forNode); + final Expression init = forNode.getInit(); + if (init != null) { + loadAndDiscard(init); + } + enterForOrWhile(forNode, forNode.getModify()); } return false; } - private void enterFor(final ForNode forNode) { - final Expression init = forNode.getInit(); - final Expression test = forNode.getTest(); - final Block body = forNode.getBody(); - final Expression modify = forNode.getModify(); - - if (init != null) { - init.accept(this); - } - - final Label loopLabel = new Label("loop"); - final Label testLabel = new Label("test"); - - method._goto(testLabel); - method.label(loopLabel); - body.accept(this); - method.label(forNode.getContinueLabel()); - - if (!body.isTerminal() && modify != null) { - load(modify); - } - - method.label(testLabel); - if (test != null) { - new BranchOptimizer(this, method).execute(test, loopLabel, true); - } else { - method._goto(loopLabel); - } - - method.label(forNode.getBreakLabel()); - } - private void enterForIn(final ForNode forNode) { - final Block body = forNode.getBody(); - final Expression modify = forNode.getModify(); - - final Symbol iter = forNode.getIterator(); - final Label loopLabel = new Label("loop"); - - final Expression init = forNode.getInit(); - - load(modify, Type.OBJECT); + loadExpression(forNode.getModify(), TypeBounds.OBJECT); method.invoke(forNode.isForEach() ? ScriptRuntime.TO_VALUE_ITERATOR : ScriptRuntime.TO_PROPERTY_ITERATOR); - method.store(iter); - method._goto(forNode.getContinueLabel()); - method.label(loopLabel); + final Symbol iterSymbol = forNode.getIterator(); + final int iterSlot = iterSymbol.getSlot(Type.OBJECT); + method.store(iterSymbol, ITERATOR_TYPE); + + method.beforeJoinPoint(forNode); + + final Label continueLabel = forNode.getContinueLabel(); + final Label breakLabel = forNode.getBreakLabel(); + + method.label(continueLabel); + method.load(ITERATOR_TYPE, iterSlot); + method.invoke(interfaceCallNoLookup(ITERATOR_CLASS, "hasNext", boolean.class)); + final JoinPredecessorExpression test = forNode.getTest(); + final Block body = forNode.getBody(); + if(LocalVariableConversion.hasLiveConversion(test)) { + final Label afterConversion = new Label("for_in_after_test_conv"); + method.ifne(afterConversion); + method.beforeJoinPoint(test); + method._goto(breakLabel); + method.label(afterConversion); + } else { + method.ifeq(breakLabel); + } - new Store<Expression>(init) { + new Store<Expression>(forNode.getInit()) { @Override protected void storeNonDiscard() { - return; + // This expression is neither part of a discard, nor needs to be left on the stack after it was + // stored, so we override storeNonDiscard to be a no-op. } + @Override protected void evaluate() { - method.load(iter); - method.invoke(interfaceCallNoLookup(Iterator.class, "next", Object.class)); + new OptimisticOperation((Optimistic)forNode.getInit(), TypeBounds.UNBOUNDED) { + @Override + void loadStack() { + method.load(ITERATOR_TYPE, iterSlot); + } + + @Override + void consumeStack() { + method.invoke(interfaceCallNoLookup(ITERATOR_CLASS, "next", Object.class)); + convertOptimisticReturnValue(); + } + }.emit(); } }.store(); - body.accept(this); - method.label(forNode.getContinueLabel()); - method.load(iter); - method.invoke(interfaceCallNoLookup(Iterator.class, "hasNext", boolean.class)); - method.ifne(loopLabel); - method.label(forNode.getBreakLabel()); + if(method.isReachable()) { + method._goto(continueLabel); + } + method.label(breakLabel); } /** @@ -955,13 +1674,16 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex * @param block block with local vars. */ private void initLocals(final Block block) { - lc.nextFreeSlot(block); + lc.onEnterBlock(block); final boolean isFunctionBody = lc.isFunctionBody(); - final FunctionNode function = lc.getCurrentFunction(); if (isFunctionBody) { - if(method.hasScope()) { + initializeMethodParameters(function); + if(!function.isVarArg()) { + expandParameterSlots(function); + } + if (method.hasScope()) { if (function.needsParentScope()) { method.loadCompilerConstant(CALLEE); method.invoke(ScriptFunction.GET_SCOPE); @@ -988,76 +1710,173 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex // TODO for LET we can do better: if *block* does not contain any eval/with, we don't need its vars in scope. - final List<String> nameList = new ArrayList<>(); - final List<Symbol> locals = new ArrayList<>(); - - // Initalize symbols and values - final List<Symbol> newSymbols = new ArrayList<>(); - final List<Symbol> values = new ArrayList<>(); - final boolean hasArguments = function.needsArguments(); - + final List<MapTuple<Symbol>> tuples = new ArrayList<>(); + final Iterator<IdentNode> paramIter = function.getParameters().iterator(); for (final Symbol symbol : block.getSymbols()) { - - if (symbol.isInternal() || symbol.isThis() || symbol.isTemp()) { + if (symbol.isInternal() || symbol.isThis()) { continue; } if (symbol.isVar()) { + assert !varsInScope || symbol.isScope(); if (varsInScope || symbol.isScope()) { - nameList.add(symbol.getName()); - newSymbols.add(symbol); - values.add(null); assert symbol.isScope() : "scope for " + symbol + " should have been set in Lower already " + function.getName(); assert !symbol.hasSlot() : "slot for " + symbol + " should have been removed in Lower already" + function.getName(); + + //this tuple will not be put fielded, as it has no value, just a symbol + tuples.add(new MapTuple<Symbol>(symbol.getName(), symbol, null)); } else { - assert symbol.hasSlot() : symbol + " should have a slot only, no scope"; - locals.add(symbol); + assert symbol.hasSlot() || symbol.slotCount() == 0 : symbol + " should have a slot only, no scope"; } } else if (symbol.isParam() && (varsInScope || hasArguments || symbol.isScope())) { - nameList.add(symbol.getName()); - newSymbols.add(symbol); - values.add(hasArguments ? null : symbol); - assert symbol.isScope() : "scope for " + symbol + " should have been set in Lower already " + function.getName() + " varsInScope="+varsInScope+" hasArguments="+hasArguments+" symbol.isScope()=" + symbol.isScope(); + assert symbol.isScope() : "scope for " + symbol + " should have been set in AssignSymbols already " + function.getName() + " varsInScope="+varsInScope+" hasArguments="+hasArguments+" symbol.isScope()=" + symbol.isScope(); assert !(hasArguments && symbol.hasSlot()) : "slot for " + symbol + " should have been removed in Lower already " + function.getName(); + + final Type paramType; + final Symbol paramSymbol; + + if (hasArguments) { + assert !symbol.hasSlot() : "slot for " + symbol + " should have been removed in Lower already "; + paramSymbol = null; + paramType = null; + } else { + paramSymbol = symbol; + // NOTE: We're relying on the fact here that Block.symbols is a LinkedHashMap, hence it will + // return symbols in the order they were defined, and parameters are defined in the same order + // they appear in the function. That's why we can have a single pass over the parameter list + // with an iterator, always just scanning forward for the next parameter that matches the symbol + // name. + for(;;) { + final IdentNode nextParam = paramIter.next(); + if(nextParam.getName().equals(symbol.getName())) { + paramType = nextParam.getType(); + break; + } + } + } + + tuples.add(new MapTuple<Symbol>(symbol.getName(), symbol, paramType, paramSymbol) { + //this symbol will be put fielded, we can't initialize it as undefined with a known type + @Override + public Class<?> getValueType() { + if (OBJECT_FIELDS_ONLY || value == null || paramType == null) { + return Object.class; + } + return paramType.isBoolean() ? Object.class : paramType.getTypeClass(); + } + }); } } - // we may have locals that need to be initialized - initSymbols(locals); - /* * Create a new object based on the symbols and values, generate * bootstrap code for object */ - new FieldObjectCreator<Symbol>(this, nameList, newSymbols, values, true, hasArguments) { + new FieldObjectCreator<Symbol>(this, tuples, true, hasArguments) { @Override - protected void loadValue(final Symbol value) { - method.load(value); + protected void loadValue(final Symbol value, final Type type) { + method.load(value, type); } }.makeObject(method); - - // runScript(): merge scope into global + // program function: merge scope into global if (isFunctionBody && function.isProgram()) { method.invoke(ScriptRuntime.MERGE_SCOPE); } method.storeCompilerConstant(SCOPE); - } else { + if(!isFunctionBody) { + // Function body doesn't need a try/catch to restore scope, as it'd be a dead store anyway. Allowing it + // actually causes issues with UnwarrantedOptimismException handlers as ASM will sort this handler to + // the top of the exception handler table, so it'll be triggered instead of the UOE handlers. + final Label scopeEntryLabel = new Label("scope_entry"); + scopeEntryLabels.push(scopeEntryLabel); + method.label(scopeEntryLabel); + } + } else if (isFunctionBody && function.isVarArg()) { // Since we don't have a scope, parameters didn't get assigned array indices by the FieldObjectCreator, so // we need to assign them separately here. int nextParam = 0; - if (isFunctionBody && function.isVarArg()) { - for (final IdentNode param : function.getParameters()) { - param.getSymbol().setFieldIndex(nextParam++); - } + for (final IdentNode param : function.getParameters()) { + param.getSymbol().setFieldIndex(nextParam++); } - - initSymbols(block.getSymbols()); } // Debugging: print symbols? @see --print-symbols flag - printSymbols(block, (isFunctionBody ? "Function " : "Block in ") + (function.getIdent() == null ? "<anonymous>" : function.getIdent().getName())); + printSymbols(block, function, (isFunctionBody ? "Function " : "Block in ") + (function.getIdent() == null ? "<anonymous>" : function.getIdent().getName())); + } + + /** + * Incoming method parameters are always declared on method entry; declare them in the local variable table. + * @param function function for which code is being generated. + */ + private void initializeMethodParameters(final FunctionNode function) { + final Label functionStart = new Label("fn_start"); + method.label(functionStart); + int nextSlot = 0; + if(function.needsCallee()) { + initializeInternalFunctionParameter(CALLEE, function, functionStart, nextSlot++); + } + initializeInternalFunctionParameter(THIS, function, functionStart, nextSlot++); + if(function.isVarArg()) { + initializeInternalFunctionParameter(VARARGS, function, functionStart, nextSlot++); + } else { + for(final IdentNode param: function.getParameters()) { + final Symbol symbol = param.getSymbol(); + if(symbol.isBytecodeLocal()) { + method.initializeMethodParameter(symbol, param.getType(), functionStart); + } + } + } + } + + private void initializeInternalFunctionParameter(final CompilerConstants cc, final FunctionNode fn, final Label functionStart, final int slot) { + final Symbol symbol = initializeInternalFunctionOrSplitParameter(cc, fn, functionStart, slot); + // Internal function params (:callee, this, and :varargs) are never expanded to multiple slots + assert symbol.getFirstSlot() == slot; + } + + private Symbol initializeInternalFunctionOrSplitParameter(final CompilerConstants cc, final FunctionNode fn, final Label functionStart, final int slot) { + final Symbol symbol = fn.getBody().getExistingSymbol(cc.symbolName()); + final Type type = Type.typeFor(cc.type()); + method.initializeMethodParameter(symbol, type, functionStart); + method.onLocalStore(type, slot); + return symbol; + } + + /** + * Parameters come into the method packed into local variable slots next to each other. Nashorn on the other hand + * can use 1-6 slots for a local variable depending on all the types it needs to store. When this method is invoked, + * the symbols are already allocated such wider slots, but the values are still in tightly packed incoming slots, + * and we need to spread them into their new locations. + * @param function the function for which parameter-spreading code needs to be emitted + */ + private void expandParameterSlots(final FunctionNode function) { + final List<IdentNode> parameters = function.getParameters(); + // Calculate the total number of incoming parameter slots + int currentIncomingSlot = function.needsCallee() ? 2 : 1; + for(final IdentNode parameter: parameters) { + currentIncomingSlot += parameter.getType().getSlots(); + } + // Starting from last parameter going backwards, move the parameter values into their new slots. + for(int i = parameters.size(); i-- > 0;) { + final IdentNode parameter = parameters.get(i); + final Type parameterType = parameter.getType(); + final int typeWidth = parameterType.getSlots(); + currentIncomingSlot -= typeWidth; + final Symbol symbol = parameter.getSymbol(); + final int slotCount = symbol.slotCount(); + assert slotCount > 0; + // Scoped parameters must not hold more than one value + assert symbol.isBytecodeLocal() || slotCount == typeWidth; + + // Mark it as having its value stored into it by the method invocation. + method.onLocalStore(parameterType, currentIncomingSlot); + if(currentIncomingSlot != symbol.getSlot(parameterType)) { + method.load(parameterType, currentIncomingSlot); + method.store(symbol, parameterType); + } + } } private void initArguments(final FunctionNode function) { @@ -1075,15 +1894,45 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex method.storeCompilerConstant(ARGUMENTS); } + private boolean skipFunction(final FunctionNode functionNode) { + final ScriptEnvironment env = compiler.getScriptEnvironment(); + final boolean lazy = env._lazy_compilation; + final boolean onDemand = compiler.isOnDemandCompilation(); + + // If this is on-demand or lazy compilation, don't compile a nested (not topmost) function. + if((onDemand || lazy) && lc.getOutermostFunction() != functionNode) { + return true; + } + + // If lazy compiling with optimistic types, don't compile the program eagerly either. It will soon be + // invalidated anyway. In presence of a class cache, this further means that an obsoleted program version + // lingers around. Also, currently loading previously persisted optimistic types information only works if + // we're on-demand compiling a function, so with this strategy the :program method can also have the warmup + // benefit of using previously persisted types. + // + // NOTE that this means the first compiled class will effectively just have a :createProgramFunction method, and + // the RecompilableScriptFunctionData (RSFD) object in its constants array. It won't even have the :program + // method. This is by design. It does mean that we're wasting one compiler execution (and we could minimize this + // by just running it up to scope depth calculation, which creates the RSFDs and then this limited codegen). + // We could emit an initial separate compile unit with the initial version of :program in it to better utilize + // the compilation pipeline, but that would need more invasive changes, as currently the assumption that + // :program is emitted into the first compilation unit of the function lives in many places. + return !onDemand && lazy && env._optimistic_types && functionNode.isProgram(); + } + @Override public boolean enterFunctionNode(final FunctionNode functionNode) { - if (functionNode.isLazy()) { - // Must do it now; can't postpone it until leaveFunctionNode() - newFunctionObject(functionNode, functionNode); + final int fnId = functionNode.getId(); + + if (skipFunction(functionNode)) { + // In case we are not generating code for the function, we must create or retrieve the function object and + // load it on the stack here. + newFunctionObject(functionNode, false); return false; } final String fnName = functionNode.getName(); + // NOTE: we only emit the method for a function with the given name once. We can have multiple functions with // the same name as a result of inlining finally blocks. However, in the future -- with type specialization, // notably -- we might need to check for both name *and* signature. Of course, even that might not be @@ -1092,35 +1941,67 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex // to decide to either generate a unique method for each inlined copy of the function, maybe figure out its // exact type closure and deduplicate based on that, or just decide that functions in finally blocks aren't // worth it, and generate one method with most generic type closure. - if(!emittedMethods.contains(fnName)) { - LOG.info("=== BEGIN ", fnName); + if (!emittedMethods.contains(fnName)) { + log.info("=== BEGIN ", fnName); assert functionNode.getCompileUnit() != null : "no compile unit for " + fnName + " " + Debug.id(functionNode); unit = lc.pushCompileUnit(functionNode.getCompileUnit()); assert lc.hasCompileUnits(); - method = lc.pushMethodEmitter(unit.getClassEmitter().method(functionNode)); + final ClassEmitter classEmitter = unit.getClassEmitter(); + pushMethodEmitter(isRestOf() ? classEmitter.restOfMethod(functionNode) : classEmitter.method(functionNode)); + method.setPreventUndefinedLoad(); + if(useOptimisticTypes()) { + lc.pushUnwarrantedOptimismHandlers(); + } + // new method - reset last line number lastLineNumber = -1; - // Mark end for variable tables. + method.begin(); + + if (isRestOf()) { + final ContinuationInfo ci = new ContinuationInfo(); + fnIdToContinuationInfo.put(fnId, ci); + method.gotoLoopStart(ci.getHandlerLabel()); + } } return true; } + private void pushMethodEmitter(final MethodEmitter newMethod) { + method = lc.pushMethodEmitter(newMethod); + catchLabels.push(METHOD_BOUNDARY); + } + + private void popMethodEmitter() { + method = lc.popMethodEmitter(method); + assert catchLabels.peek() == METHOD_BOUNDARY; + catchLabels.pop(); + } + @Override public Node leaveFunctionNode(final FunctionNode functionNode) { try { - if(emittedMethods.add(functionNode.getName())) { + final boolean markOptimistic; + if (emittedMethods.add(functionNode.getName())) { + markOptimistic = generateUnwarrantedOptimismExceptionHandlers(functionNode); + generateContinuationHandler(); method.end(); // wrap up this method unit = lc.popCompileUnit(functionNode.getCompileUnit()); - method = lc.popMethodEmitter(method); - LOG.info("=== END ", functionNode.getName()); + popMethodEmitter(); + log.info("=== END ", functionNode.getName()); + } else { + markOptimistic = false; + } + + FunctionNode newFunctionNode = functionNode.setState(lc, CompilationState.BYTECODE_GENERATED); + if (markOptimistic) { + newFunctionNode = newFunctionNode.setFlag(lc, FunctionNode.IS_DEOPTIMIZABLE); } - final FunctionNode newFunctionNode = functionNode.setState(lc, CompilationState.EMITTED); - newFunctionObject(newFunctionNode, functionNode); + newFunctionObject(newFunctionNode, true); return newFunctionNode; } catch (final Throwable t) { Context.printStackTrace(t); @@ -1131,62 +2012,75 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex } @Override - public boolean enterIdentNode(final IdentNode identNode) { - return false; - } - - @Override public boolean enterIfNode(final IfNode ifNode) { - lineNumber(ifNode); + if(!method.isReachable()) { + return false; + } + enterStatement(ifNode); final Expression test = ifNode.getTest(); final Block pass = ifNode.getPass(); final Block fail = ifNode.getFail(); - final Label failLabel = new Label("if_fail"); - final Label afterLabel = fail == null ? failLabel : new Label("if_done"); + if (Expression.isAlwaysTrue(test)) { + loadAndDiscard(test); + pass.accept(this); + return false; + } else if (Expression.isAlwaysFalse(test)) { + loadAndDiscard(test); + if (fail != null) { + fail.accept(this); + } + return false; + } - new BranchOptimizer(this, method).execute(test, failLabel, false); + final boolean hasFailConversion = LocalVariableConversion.hasLiveConversion(ifNode); - boolean passTerminal = false; - boolean failTerminal = false; + final Label failLabel = new Label("if_fail"); + final Label afterLabel = (fail == null && !hasFailConversion) ? null : new Label("if_done"); + + emitBranch(test, failLabel, false); pass.accept(this); - if (!pass.hasTerminalFlags()) { + if(method.isReachable() && afterLabel != null) { method._goto(afterLabel); //don't fallthru to fail block - } else { - passTerminal = pass.isTerminal(); } + method.label(failLabel); if (fail != null) { - method.label(failLabel); fail.accept(this); - failTerminal = fail.isTerminal(); + } else if(hasFailConversion) { + method.beforeJoinPoint(ifNode); } - //if if terminates, put the after label there - if (!passTerminal || !failTerminal) { + if(afterLabel != null && afterLabel.isReachable()) { method.label(afterLabel); } return false; } - @Override - public boolean enterIndexNode(final IndexNode indexNode) { - load(indexNode); - return false; + private void emitBranch(final Expression test, final Label label, final boolean jumpWhenTrue) { + new BranchOptimizer(this, method).execute(test, label, jumpWhenTrue); + } + + private void enterStatement(final Statement statement) { + lineNumber(statement); } private void lineNumber(final Statement statement) { lineNumber(statement.getLineNumber()); } - private void lineNumber(int lineNumber) { - if (lineNumber != lastLineNumber) { + private void lineNumber(final int lineNumber) { + if (lineNumber != lastLineNumber && lineNumber != Node.NO_LINE_NUMBER) { method.lineNumber(lineNumber); + lastLineNumber = lineNumber; } - lastLineNumber = lineNumber; + } + + int getLastLineNumber() { + return lastLineNumber; } /** @@ -1219,26 +2113,35 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex unit = lc.pushCompileUnit(arrayUnit.getCompileUnit()); final String className = unit.getUnitClassName(); + assert unit != null; final String name = currentFunction.uniqueName(SPLIT_PREFIX.symbolName()); final String signature = methodDescriptor(type, ScriptFunction.class, Object.class, ScriptObject.class, type); - final MethodEmitter me = unit.getClassEmitter().method(EnumSet.of(Flag.PUBLIC, Flag.STATIC), name, signature); - method = lc.pushMethodEmitter(me); + pushMethodEmitter(unit.getClassEmitter().method(EnumSet.of(Flag.PUBLIC, Flag.STATIC), name, signature)); method.setFunctionNode(currentFunction); method.begin(); - fixScopeSlot(currentFunction); + defineCommonSplitMethodParameters(); + defineSplitMethodParameter(CompilerConstants.SPLIT_ARRAY_ARG.slot(), arrayType); + + // NOTE: when this is no longer needed, SplitIntoFunctions will no longer have to add IS_SPLIT + // to synthetic functions, and FunctionNode.needsCallee() will no longer need to test for isSplit(). + final int arraySlot = fixScopeSlot(currentFunction, 3); - method.load(arrayType, SPLIT_ARRAY_ARG.slot()); + lc.enterSplitNode(); for (int i = arrayUnit.getLo(); i < arrayUnit.getHi(); i++) { + method.load(arrayType, arraySlot); storeElement(nodes, elementType, postsets[i]); } + method.load(arrayType, arraySlot); method._return(); + lc.exitSplitNode(); method.end(); - method = lc.popMethodEmitter(me); + lc.releaseSlots(); + popMethodEmitter(); assert method == savedMethod; method.loadCompilerConstant(CALLEE); @@ -1255,15 +2158,19 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex return method; } - for (final int postset : postsets) { - storeElement(nodes, elementType, postset); + if(postsets.length > 0) { + final int arraySlot = method.getUsedSlotsWithLiveTemporaries(); + method.storeTemp(arrayType, arraySlot); + for (final int postset : postsets) { + method.load(arrayType, arraySlot); + storeElement(nodes, elementType, postset); + } + method.load(arrayType, arraySlot); } - return method; } private void storeElement(final Expression[] nodes, final Type elementType, final int index) { - method.dup(); method.load(index); final Expression element = nodes[index]; @@ -1271,7 +2178,7 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex if (element == null) { method.loadEmpty(elementType); } else { - load(element, elementType); + loadExpressionAsType(element, elementType); } method.arraystore(); @@ -1284,7 +2191,7 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex for (int i = 0; i < args.size(); i++) { method.dup(); method.load(i); - load(args.get(i), Type.OBJECT); //has to be upcast to object or we fail + loadExpression(args.get(i), TypeBounds.OBJECT); // variable arity methods always take objects method.arraystore(); } @@ -1314,44 +2221,48 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex * @param object object to load */ void loadConstant(final Object object) { - final String unitClassName = unit.getUnitClassName(); - final ClassEmitter classEmitter = unit.getClassEmitter(); + loadConstant(object, unit, method); + } + + private void loadConstant(final Object object, final CompileUnit compileUnit, final MethodEmitter methodEmitter) { + final String unitClassName = compileUnit.getUnitClassName(); + final ClassEmitter classEmitter = compileUnit.getClassEmitter(); final int index = compiler.getConstantData().add(object); final Class<?> cls = object.getClass(); if (cls == PropertyMap.class) { - method.load(index); - method.invokestatic(unitClassName, GET_MAP.symbolName(), methodDescriptor(PropertyMap.class, int.class)); + methodEmitter.load(index); + methodEmitter.invokestatic(unitClassName, GET_MAP.symbolName(), methodDescriptor(PropertyMap.class, int.class)); classEmitter.needGetConstantMethod(PropertyMap.class); } else if (cls.isArray()) { - method.load(index); + methodEmitter.load(index); final String methodName = ClassEmitter.getArrayMethodName(cls); - method.invokestatic(unitClassName, methodName, methodDescriptor(cls, int.class)); + methodEmitter.invokestatic(unitClassName, methodName, methodDescriptor(cls, int.class)); classEmitter.needGetConstantMethod(cls); } else { - method.loadConstants().load(index).arrayload(); + methodEmitter.loadConstants().load(index).arrayload(); if (object instanceof ArrayData) { // avoid cast to non-public ArrayData subclass - method.checkcast(ArrayData.class); - method.invoke(virtualCallNoLookup(ArrayData.class, "copy", ArrayData.class)); + methodEmitter.checkcast(ArrayData.class); + methodEmitter.invoke(virtualCallNoLookup(ArrayData.class, "copy", ArrayData.class)); } else if (cls != Object.class) { - method.checkcast(cls); + methodEmitter.checkcast(cls); } } } // literal values - private MethodEmitter loadLiteral(final LiteralNode<?> node, final Type type) { + private void loadLiteral(final LiteralNode<?> node, final TypeBounds resultBounds) { final Object value = node.getValue(); if (value == null) { method.loadNull(); } else if (value instanceof Undefined) { - method.loadUndefined(Type.OBJECT); + method.loadUndefined(resultBounds.within(Type.OBJECT)); } else if (value instanceof String) { final String string = (String)value; - if (string.length() > (MethodEmitter.LARGE_STRING_THRESHOLD / 3)) { // 3 == max bytes per encoded char + if (string.length() > MethodEmitter.LARGE_STRING_THRESHOLD / 3) { // 3 == max bytes per encoded char loadConstant(string); } else { method.load(string); @@ -1361,31 +2272,40 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex } else if (value instanceof Boolean) { method.load((Boolean)value); } else if (value instanceof Integer) { - if(type.isEquivalentTo(Type.NUMBER)) { + if(!resultBounds.canBeNarrowerThan(Type.OBJECT)) { + method.load((Integer)value); + method.convert(Type.OBJECT); + } else if(!resultBounds.canBeNarrowerThan(Type.NUMBER)) { method.load(((Integer)value).doubleValue()); - } else if(type.isEquivalentTo(Type.LONG)) { + } else if(!resultBounds.canBeNarrowerThan(Type.LONG)) { method.load(((Integer)value).longValue()); } else { method.load((Integer)value); } } else if (value instanceof Long) { - if(type.isEquivalentTo(Type.NUMBER)) { + if(!resultBounds.canBeNarrowerThan(Type.OBJECT)) { + method.load((Long)value); + method.convert(Type.OBJECT); + } else if(!resultBounds.canBeNarrowerThan(Type.NUMBER)) { method.load(((Long)value).doubleValue()); } else { method.load((Long)value); } } else if (value instanceof Double) { - method.load((Double)value); + if(!resultBounds.canBeNarrowerThan(Type.OBJECT)) { + method.load((Double)value); + method.convert(Type.OBJECT); + } else { + method.load((Double)value); + } } else if (node instanceof ArrayLiteralNode) { final ArrayLiteralNode arrayLiteral = (ArrayLiteralNode)node; final ArrayType atype = arrayLiteral.getArrayType(); loadArray(arrayLiteral, atype); globalAllocateArray(atype); } else { - assert false : "Unknown literal for " + node.getClass() + " " + value.getClass() + " " + value; + throw new UnsupportedOperationException("Unknown literal for " + node.getClass() + " " + value.getClass() + " " + value); } - - return method; } private MethodEmitter loadRegexToken(final RegexToken value) { @@ -1422,35 +2342,65 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex return method; } - @Override - public boolean enterLiteralNode(final LiteralNode<?> literalNode) { - return enterLiteralNode(literalNode, literalNode.getType()); - } + /** + * Check if a property value contains a particular program point + * @param value value + * @param pp program point + * @return true if it's there. + */ + private static boolean propertyValueContains(final Expression value, final int pp) { + return new Supplier<Boolean>() { + boolean contains; - private boolean enterLiteralNode(final LiteralNode<?> literalNode, final Type type) { - assert literalNode.getSymbol() != null : literalNode + " has no symbol"; - loadLiteral(literalNode, type).convert(type).store(literalNode.getSymbol()); - return false; + @Override + public Boolean get() { + value.accept(new NodeVisitor<LexicalContext>(new LexicalContext()) { + @Override + public boolean enterFunctionNode(final FunctionNode functionNode) { + return false; + } + + @Override + public boolean enterObjectNode(final ObjectNode objectNode) { + return false; + } + + @Override + public boolean enterDefault(final Node node) { + if (contains) { + return false; + } + if (node instanceof Optimistic && ((Optimistic)node).getProgramPoint() == pp) { + contains = true; + return false; + } + return true; + } + }); + + return contains; + } + }.get(); } - @Override - public boolean enterObjectNode(final ObjectNode objectNode) { + private void loadObjectNode(final ObjectNode objectNode) { final List<PropertyNode> elements = objectNode.getElements(); - final List<String> keys = new ArrayList<>(); - final List<Symbol> symbols = new ArrayList<>(); - final List<Expression> values = new ArrayList<>(); + final List<MapTuple<Expression>> tuples = new ArrayList<>(); + final List<PropertyNode> gettersSetters = new ArrayList<>(); + final int ccp = getCurrentContinuationEntryPoint(); - boolean hasGettersSetters = false; Expression protoNode = null; + boolean restOfProperty = false; - for (PropertyNode propertyNode: elements) { - final Expression value = propertyNode.getValue(); - final String key = propertyNode.getKeyName(); - final Symbol symbol = value == null ? null : propertyNode.getKey().getSymbol(); + for (final PropertyNode propertyNode : elements) { + final Expression value = propertyNode.getValue(); + final String key = propertyNode.getKeyName(); + // Just use a pseudo-symbol. We just need something non null; use the name and zero flags. + final Symbol symbol = value == null ? null : new Symbol(key, 0); if (value == null) { - hasGettersSetters = true; + gettersSetters.add(propertyNode); } else if (propertyNode.getKey() instanceof IdentNode && key.equals(ScriptObject.PROTO_PROPERTY_NAME)) { // ES6 draft compliant __proto__ inside object literal @@ -1459,89 +2409,84 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex continue; } - keys.add(key); - symbols.add(symbol); - values.add(value); - } + restOfProperty |= + value != null && + isValid(ccp) && + propertyValueContains(value, ccp); - if (elements.size() > OBJECT_SPILL_THRESHOLD) { - new SpillObjectCreator(this, keys, symbols, values).makeObject(method); - } else { - new FieldObjectCreator<Expression>(this, keys, symbols, values) { + //for literals, a value of null means object type, i.e. the value null or getter setter function + //(I think) + final Class<?> valueType = (OBJECT_FIELDS_ONLY || value == null || value.getType().isBoolean()) ? Object.class : value.getType().getTypeClass(); + tuples.add(new MapTuple<Expression>(key, symbol, Type.typeFor(valueType), value) { @Override - protected void loadValue(final Expression node) { - load(node); + public Class<?> getValueType() { + return type.getTypeClass(); } + }); + } - /** - * Ensure that the properties start out as object types so that - * we can do putfield initializations instead of dynamicSetIndex - * which would be the case to determine initial property type - * otherwise. - * - * Use case, it's very expensive to do a million var x = {a:obj, b:obj} - * just to have to invalidate them immediately on initialization - * - * see NASHORN-594 - */ + final ObjectCreator<?> oc; + if (elements.size() > OBJECT_SPILL_THRESHOLD) { + oc = new SpillObjectCreator(this, tuples); + } else { + oc = new FieldObjectCreator<Expression>(this, tuples) { @Override - protected MapCreator newMapCreator(final Class<?> fieldObjectClass) { - return new MapCreator(fieldObjectClass, keys, symbols) { - @Override - protected int getPropertyFlags(final Symbol symbol, final boolean hasArguments) { - return super.getPropertyFlags(symbol, hasArguments) | Property.IS_ALWAYS_OBJECT; - } - }; - } - - }.makeObject(method); + protected void loadValue(final Expression node, final Type type) { + loadExpressionAsType(node, type); + }}; + } + oc.makeObject(method); + + //if this is a rest of method and our continuation point was found as one of the values + //in the properties above, we need to reset the map to oc.getMap() in the continuation + //handler + if (restOfProperty) { + final ContinuationInfo ci = getContinuationInfo(); + // Can be set at most once for a single rest-of method + assert ci.getObjectLiteralMap() == null; + ci.setObjectLiteralMap(oc.getMap()); + ci.setObjectLiteralStackDepth(method.getStackSize()); } method.dup(); if (protoNode != null) { - load(protoNode); + loadExpressionAsObject(protoNode); // take care of { __proto__: 34 } or some such! method.convert(Type.OBJECT); method.invoke(ScriptObject.SET_PROTO_FROM_LITERAL); } else { - globalObjectPrototype(); - method.invoke(ScriptObject.SET_PROTO); + method.invoke(ScriptObject.SET_GLOBAL_OBJECT_PROTO); } - if (hasGettersSetters) { - for (final PropertyNode propertyNode : elements) { - final FunctionNode getter = propertyNode.getGetter(); - final FunctionNode setter = propertyNode.getSetter(); - - if (getter == null && setter == null) { - continue; - } - - method.dup().loadKey(propertyNode.getKey()); + for (final PropertyNode propertyNode : gettersSetters) { + final FunctionNode getter = propertyNode.getGetter(); + final FunctionNode setter = propertyNode.getSetter(); - if (getter == null) { - method.loadNull(); - } else { - getter.accept(this); - } + assert getter != null || setter != null; - if (setter == null) { - method.loadNull(); - } else { - setter.accept(this); - } + method.dup().loadKey(propertyNode.getKey()); + if (getter == null) { + method.loadNull(); + } else { + getter.accept(this); + } - method.invoke(ScriptObject.SET_USER_ACCESSORS); + if (setter == null) { + method.loadNull(); + } else { + setter.accept(this); } - } - method.store(objectNode.getSymbol()); - return false; + method.invoke(ScriptObject.SET_USER_ACCESSORS); + } } @Override public boolean enterReturnNode(final ReturnNode returnNode) { - lineNumber(returnNode); + if(!method.isReachable()) { + return false; + } + enterStatement(returnNode); method.registerReturn(); @@ -1549,7 +2494,7 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex final Expression expression = returnNode.getExpression(); if (expression != null) { - load(expression); + loadExpressionUnbounded(expression); } else { method.loadUndefined(returnType); } @@ -1559,11 +2504,83 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex return false; } + private boolean undefinedCheck(final RuntimeNode runtimeNode, final List<Expression> args) { + final Request request = runtimeNode.getRequest(); + + if (!Request.isUndefinedCheck(request)) { + return false; + } + + final Expression lhs = args.get(0); + final Expression rhs = args.get(1); + + final Symbol lhsSymbol = lhs instanceof IdentNode ? ((IdentNode)lhs).getSymbol() : null; + final Symbol rhsSymbol = rhs instanceof IdentNode ? ((IdentNode)rhs).getSymbol() : null; + // One must be a "undefined" identifier, otherwise we can't get here + assert lhsSymbol != null || rhsSymbol != null; + + final Symbol undefinedSymbol; + if (isUndefinedSymbol(lhsSymbol)) { + undefinedSymbol = lhsSymbol; + } else { + assert isUndefinedSymbol(rhsSymbol); + undefinedSymbol = rhsSymbol; + } + + assert undefinedSymbol != null; //remove warning + if (!undefinedSymbol.isScope()) { + return false; //disallow undefined as local var or parameter + } + + if (lhsSymbol == undefinedSymbol && lhs.getType().isPrimitive()) { + //we load the undefined first. never mind, because this will deoptimize anyway + return false; + } + + if(isDeoptimizedExpression(lhs)) { + // This is actually related to "lhs.getType().isPrimitive()" above: any expression being deoptimized in + // the current chain of rest-of compilations used to have a type narrower than Object (so it was primitive). + // We must not perform undefined check specialization for them, as then we'd violate the basic rule of + // "Thou shalt not alter the stack shape between a deoptimized method and any of its (transitive) rest-ofs." + return false; + } + + //make sure that undefined has not been overridden or scoped as a local var + //between us and global + if (!compiler.isGlobalSymbol(lc.getCurrentFunction(), "undefined")) { + return false; + } + + final boolean isUndefinedCheck = request == Request.IS_UNDEFINED; + final Expression expr = undefinedSymbol == lhsSymbol ? rhs : lhs; + if (expr.getType().isPrimitive()) { + loadAndDiscard(expr); //throw away lhs, but it still needs to be evaluated for side effects, even if not in scope, as it can be optimistic + method.load(!isUndefinedCheck); + } else { + final Label checkTrue = new Label("ud_check_true"); + final Label end = new Label("end"); + loadExpressionAsObject(expr); + method.loadUndefined(Type.OBJECT); + method.if_acmpeq(checkTrue); + method.load(!isUndefinedCheck); + method._goto(end); + method.label(checkTrue); + method.load(isUndefinedCheck); + method.label(end); + } + + return true; + } + + private static boolean isUndefinedSymbol(final Symbol symbol) { + return symbol != null && "undefined".equals(symbol.getName()); + } + private static boolean isNullLiteral(final Node node) { return node instanceof LiteralNode<?> && ((LiteralNode<?>) node).isNull(); } - private boolean nullCheck(final RuntimeNode runtimeNode, final List<Expression> args, final String signature) { + private boolean nullCheck(final RuntimeNode runtimeNode, final List<Expression> args) { final Request request = runtimeNode.getRequest(); if (!Request.isEQ(request) && !Request.isNE(request)) { @@ -1581,344 +2598,239 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex rhs = tmp; } + if (!isNullLiteral(rhs)) { + return false; + } + + if (!lhs.getType().isObject()) { + return false; + } + + if(isDeoptimizedExpression(lhs)) { + // This is actually related to "!lhs.getType().isObject()" above: any expression being deoptimized in + // the current chain of rest-of compilations used to have a type narrower than Object. We must not + // perform null check specialization for them, as then we'd no longer be loading aconst_null on stack + // and thus violate the basic rule of "Thou shalt not alter the stack shape between a deoptimized + // method and any of its (transitive) rest-ofs." + // NOTE also that if we had a representation for well-known constants (e.g. null, 0, 1, -1, etc.) in + // Label$Stack.localLoads then this wouldn't be an issue, as we would never (somewhat ridiculously) + // allocate a temporary local to hold the result of aconst_null before attempting an optimistic + // operation. + return false; + } + // this is a null literal check, so if there is implicit coercion // involved like {D}x=null, we will fail - this is very rare - if (isNullLiteral(rhs) && lhs.getType().isObject()) { - final Label trueLabel = new Label("trueLabel"); - final Label falseLabel = new Label("falseLabel"); - final Label endLabel = new Label("end"); + final Label trueLabel = new Label("trueLabel"); + final Label falseLabel = new Label("falseLabel"); + final Label endLabel = new Label("end"); + + loadExpressionUnbounded(lhs); //lhs + final Label popLabel; + if (!Request.isStrict(request)) { + method.dup(); //lhs lhs + popLabel = new Label("pop"); + } else { + popLabel = null; + } - load(lhs); - method.dup(); - if (Request.isEQ(request)) { - method.ifnull(trueLabel); - } else if (Request.isNE(request)) { - method.ifnonnull(trueLabel); - } else { - assert false : "Invalid request " + request; + if (Request.isEQ(request)) { + method.ifnull(!Request.isStrict(request) ? popLabel : trueLabel); + if (!Request.isStrict(request)) { + method.loadUndefined(Type.OBJECT); + method.if_acmpeq(trueLabel); } - method.label(falseLabel); - load(rhs); - method.invokestatic(CompilerConstants.className(ScriptRuntime.class), request.toString(), signature); + method.load(false); method._goto(endLabel); - + if (!Request.isStrict(request)) { + method.label(popLabel); + method.pop(); + } method.label(trueLabel); - // if NE (not strict) this can be "undefined != null" which is supposed to be false - if (request == Request.NE) { + method.load(true); + method.label(endLabel); + } else if (Request.isNE(request)) { + method.ifnull(!Request.isStrict(request) ? popLabel : falseLabel); + if (!Request.isStrict(request)) { method.loadUndefined(Type.OBJECT); - final Label isUndefined = new Label("isUndefined"); - final Label afterUndefinedCheck = new Label("afterUndefinedCheck"); - method.if_acmpeq(isUndefined); - // not undefined - method.load(true); - method._goto(afterUndefinedCheck); - method.label(isUndefined); - method.load(false); - method.label(afterUndefinedCheck); - } else { + method.if_acmpeq(falseLabel); + } + method.label(trueLabel); + method.load(true); + method._goto(endLabel); + if (!Request.isStrict(request)) { + method.label(popLabel); method.pop(); - method.load(true); } + method.label(falseLabel); + method.load(false); method.label(endLabel); - method.convert(runtimeNode.getType()); - method.store(runtimeNode.getSymbol()); - - return true; } - return false; + assert runtimeNode.getType().isBoolean(); + method.convert(runtimeNode.getType()); + + return true; } - private boolean specializationCheck(final RuntimeNode.Request request, final Expression node, final List<Expression> args) { - if (!request.canSpecialize()) { + /** + * Was this expression or any of its subexpressions deoptimized in the current recompilation chain of rest-of methods? + * @param rootExpr the expression being tested + * @return true if the expression or any of its subexpressions was deoptimized in the current recompilation chain. + */ + private boolean isDeoptimizedExpression(final Expression rootExpr) { + if(!isRestOf()) { return false; } - - assert args.size() == 2; - final Type returnType = node.getType(); - - load(args.get(0)); - load(args.get(1)); - - Request finalRequest = request; - - //if the request is a comparison, i.e. one that can be reversed - //it keeps its semantic, but make sure that the object comes in - //last - final Request reverse = Request.reverse(request); - if (method.peekType().isObject() && reverse != null) { //rhs is object - if (!method.peekType(1).isObject()) { //lhs is not object - method.swap(); //prefer object as lhs - finalRequest = reverse; + return new Supplier<Boolean>() { + boolean contains; + @Override + public Boolean get() { + rootExpr.accept(new NodeVisitor<LexicalContext>(new LexicalContext()) { + @Override + public boolean enterFunctionNode(final FunctionNode functionNode) { + return false; + } + @Override + public boolean enterDefault(final Node node) { + if(!contains && node instanceof Optimistic) { + final int pp = ((Optimistic)node).getProgramPoint(); + contains = isValid(pp) && isContinuationEntryPoint(pp); + } + return !contains; + } + }); + return contains; } - } - - method.dynamicRuntimeCall( - new SpecializedRuntimeNode( - finalRequest, - new Type[] { - method.peekType(1), - method.peekType() - }, - returnType).getInitialName(), - returnType, - finalRequest); - - method.convert(node.getType()); - method.store(node.getSymbol()); - - return true; - } - - private static boolean isReducible(final Request request) { - return Request.isComparison(request) || request == Request.ADD; + }.get(); } - @Override - public boolean enterRuntimeNode(final RuntimeNode runtimeNode) { - /* - * First check if this should be something other than a runtime node - * AccessSpecializer might have changed the type - * - * TODO - remove this - Access Specializer will always know after Attr/Lower - */ - final List<Expression> args = runtimeNode.getArgs(); - if (runtimeNode.isPrimitive() && !runtimeNode.isFinal() && isReducible(runtimeNode.getRequest())) { - final Expression lhs = args.get(0); - assert args.size() > 1 : runtimeNode + " must have two args"; - final Expression rhs = args.get(1); - - final Type type = runtimeNode.getType(); - final Symbol symbol = runtimeNode.getSymbol(); - - switch (runtimeNode.getRequest()) { - case EQ: - case EQ_STRICT: - return enterCmp(lhs, rhs, Condition.EQ, type, symbol); - case NE: - case NE_STRICT: - return enterCmp(lhs, rhs, Condition.NE, type, symbol); - case LE: - return enterCmp(lhs, rhs, Condition.LE, type, symbol); - case LT: - return enterCmp(lhs, rhs, Condition.LT, type, symbol); - case GE: - return enterCmp(lhs, rhs, Condition.GE, type, symbol); - case GT: - return enterCmp(lhs, rhs, Condition.GT, type, symbol); - case ADD: - Type widest = Type.widest(lhs.getType(), rhs.getType()); - load(lhs, widest); - load(rhs, widest); - method.add(); - method.convert(type); - method.store(symbol); - return false; - default: - // it's ok to send this one on with only primitive arguments, maybe INSTANCEOF(true, true) or similar - // assert false : runtimeNode + " has all primitive arguments. This is an inconsistent state"; - break; - } - } - - if (nullCheck(runtimeNode, args, new FunctionSignature(false, false, runtimeNode.getType(), args).toString())) { - return false; - } - - if (!runtimeNode.isFinal() && specializationCheck(runtimeNode.getRequest(), runtimeNode, args)) { - return false; + private void loadRuntimeNode(final RuntimeNode runtimeNode) { + final List<Expression> args = new ArrayList<>(runtimeNode.getArgs()); + if (nullCheck(runtimeNode, args)) { + return; + } else if(undefinedCheck(runtimeNode, args)) { + return; } - - for (final Expression arg : args) { - load(arg, Type.OBJECT); + // Revert a false undefined check to a strict equality check + final RuntimeNode newRuntimeNode; + final Request request = runtimeNode.getRequest(); + if (Request.isUndefinedCheck(request)) { + newRuntimeNode = runtimeNode.setRequest(request == Request.IS_UNDEFINED ? Request.EQ_STRICT : Request.NE_STRICT); + } else { + newRuntimeNode = runtimeNode; } - method.invokestatic( - CompilerConstants.className(ScriptRuntime.class), - runtimeNode.getRequest().toString(), - new FunctionSignature( - false, - false, - runtimeNode.getType(), - args.size()).toString()); - method.convert(runtimeNode.getType()); - method.store(runtimeNode.getSymbol()); + new OptimisticOperation(newRuntimeNode, TypeBounds.UNBOUNDED) { + @Override + void loadStack() { + for (final Expression arg : args) { + loadExpression(arg, TypeBounds.OBJECT); + } + } + @Override + void consumeStack() { + method.invokestatic( + CompilerConstants.className(ScriptRuntime.class), + newRuntimeNode.getRequest().toString(), + new FunctionSignature( + false, + false, + newRuntimeNode.getType(), + args.size()).toString()); + } + }.emit(); - return false; + method.convert(newRuntimeNode.getType()); } - @Override - public boolean enterSplitNode(final SplitNode splitNode) { - final CompileUnit splitCompileUnit = splitNode.getCompileUnit(); + private void defineCommonSplitMethodParameters() { + defineSplitMethodParameter(0, CALLEE); + defineSplitMethodParameter(1, THIS); + defineSplitMethodParameter(2, SCOPE); + } - final FunctionNode fn = lc.getCurrentFunction(); - final String className = splitCompileUnit.getUnitClassName(); - final String name = splitNode.getName(); - - final Class<?> rtype = fn.getReturnType().getTypeClass(); - final boolean needsArguments = fn.needsArguments(); - final Class<?>[] ptypes = needsArguments ? - new Class<?>[] {ScriptFunction.class, Object.class, ScriptObject.class, Object.class} : - new Class<?>[] {ScriptFunction.class, Object.class, ScriptObject.class}; - - final MethodEmitter caller = method; - unit = lc.pushCompileUnit(splitCompileUnit); - - final Call splitCall = staticCallNoLookup( - className, - name, - methodDescriptor(rtype, ptypes)); - - final MethodEmitter splitEmitter = - splitCompileUnit.getClassEmitter().method( - splitNode, - name, - rtype, - ptypes); - - method = lc.pushMethodEmitter(splitEmitter); - method.setFunctionNode(fn); - - assert fn.needsCallee() : "split function should require callee"; - caller.loadCompilerConstant(CALLEE); - caller.loadCompilerConstant(THIS); - caller.loadCompilerConstant(SCOPE); - if (needsArguments) { - caller.loadCompilerConstant(ARGUMENTS); - } - caller.invoke(splitCall); - caller.storeCompilerConstant(RETURN); - - method.begin(); - // Copy scope to its target slot as first thing because the original slot could be used by return symbol. - fixScopeSlot(fn); - - method.loadUndefined(fn.getReturnType()); - method.storeCompilerConstant(RETURN); + private void defineSplitMethodParameter(final int slot, final CompilerConstants cc) { + defineSplitMethodParameter(slot, Type.typeFor(cc.type())); + } - return true; + private void defineSplitMethodParameter(final int slot, final Type type) { + method.defineBlockLocalVariable(slot, slot + type.getSlots()); + method.onLocalStore(type, slot); } - private void fixScopeSlot(final FunctionNode functionNode) { + private int fixScopeSlot(final FunctionNode functionNode, final int extraSlot) { // TODO hack to move the scope to the expected slot (needed because split methods reuse the same slots as the root method) - if (functionNode.compilerConstant(SCOPE).getSlot() != SCOPE.slot()) { - method.load(Type.typeFor(ScriptObject.class), SCOPE.slot()); + final int actualScopeSlot = functionNode.compilerConstant(SCOPE).getSlot(SCOPE_TYPE); + final int defaultScopeSlot = SCOPE.slot(); + int newExtraSlot = extraSlot; + if (actualScopeSlot != defaultScopeSlot) { + if (actualScopeSlot == extraSlot) { + newExtraSlot = extraSlot + 1; + method.defineBlockLocalVariable(newExtraSlot, newExtraSlot + 1); + method.load(Type.OBJECT, extraSlot); + method.storeHidden(Type.OBJECT, newExtraSlot); + } else { + method.defineBlockLocalVariable(actualScopeSlot, actualScopeSlot + 1); + } + method.load(SCOPE_TYPE, defaultScopeSlot); method.storeCompilerConstant(SCOPE); } + return newExtraSlot; } @Override - public Node leaveSplitNode(final SplitNode splitNode) { - assert method instanceof SplitMethodEmitter; - final boolean hasReturn = method.hasReturn(); - final List<Label> targets = method.getExternalTargets(); - - try { - // Wrap up this method. - - method.loadCompilerConstant(RETURN); - method._return(lc.getCurrentFunction().getReturnType()); - method.end(); - - unit = lc.popCompileUnit(splitNode.getCompileUnit()); - method = lc.popMethodEmitter(method); - - } catch (final Throwable t) { - Context.printStackTrace(t); - final VerifyError e = new VerifyError("Code generation bug in \"" + splitNode.getName() + "\": likely stack misaligned: " + t + " " + lc.getCurrentFunction().getSource().getName()); - e.initCause(t); - throw e; - } - - // Handle return from split method if there was one. - final MethodEmitter caller = method; - final int targetCount = targets.size(); - - //no external jump targets or return in switch node - if (!hasReturn && targets.isEmpty()) { - return splitNode; - } - - caller.loadCompilerConstant(SCOPE); - caller.checkcast(Scope.class); - caller.invoke(Scope.GET_SPLIT_STATE); - - final Label breakLabel = new Label("no_split_state"); - // Split state is -1 for no split state, 0 for return, 1..n+1 for break/continue - - //the common case is that we don't need a switch - if (targetCount == 0) { - assert hasReturn; - caller.ifne(breakLabel); - //has to be zero - caller.label(new Label("split_return")); - caller.loadCompilerConstant(RETURN); - caller._return(lc.getCurrentFunction().getReturnType()); - caller.label(breakLabel); - } else { - assert !targets.isEmpty(); - - final int low = hasReturn ? 0 : 1; - final int labelCount = targetCount + 1 - low; - final Label[] labels = new Label[labelCount]; - - for (int i = 0; i < labelCount; i++) { - labels[i] = new Label(i == 0 ? "split_return" : "split_" + targets.get(i - 1)); - } - caller.tableswitch(low, targetCount, breakLabel, labels); - for (int i = low; i <= targetCount; i++) { - caller.label(labels[i - low]); - if (i == 0) { - caller.loadCompilerConstant(RETURN); - caller._return(lc.getCurrentFunction().getReturnType()); - } else { - // Clear split state. - caller.loadCompilerConstant(SCOPE); - caller.checkcast(Scope.class); - caller.load(-1); - caller.invoke(Scope.SET_SPLIT_STATE); - caller.splitAwareGoto(lc, targets.get(i - 1)); - } - } - caller.label(breakLabel); + public boolean enterSplitReturn(final SplitReturn splitReturn) { + if (method.isReachable()) { + method.loadUndefined(lc.getCurrentFunction().getReturnType())._return(); } + return false; + } - // If split has a return and caller is itself a split method it needs to propagate the return. - if (hasReturn) { - caller.setHasReturn(); + @Override + public boolean enterSetSplitState(final SetSplitState setSplitState) { + if (method.isReachable()) { + method.setSplitState(setSplitState.getState()); } - - return splitNode; + return false; } @Override public boolean enterSwitchNode(final SwitchNode switchNode) { - lineNumber(switchNode); + if(!method.isReachable()) { + return false; + } + enterStatement(switchNode); final Expression expression = switchNode.getExpression(); - final Symbol tag = switchNode.getTag(); - final boolean allInteger = tag.getSymbolType().isInteger(); final List<CaseNode> cases = switchNode.getCases(); - final CaseNode defaultCase = switchNode.getDefaultCase(); - final Label breakLabel = switchNode.getBreakLabel(); - - Label defaultLabel = breakLabel; - boolean hasDefault = false; - - if (defaultCase != null) { - defaultLabel = defaultCase.getEntry(); - hasDefault = true; - } if (cases.isEmpty()) { // still evaluate expression for side-effects. - load(expression).pop(); - method.label(breakLabel); + loadAndDiscard(expression); + return false; + } + + final CaseNode defaultCase = switchNode.getDefaultCase(); + final Label breakLabel = switchNode.getBreakLabel(); + final int liveLocalsOnBreak = method.getUsedSlotsWithLiveTemporaries(); + + if (defaultCase != null && cases.size() == 1) { + // default case only + assert cases.get(0) == defaultCase; + loadAndDiscard(expression); + defaultCase.getBody().accept(this); + method.breakLabel(breakLabel, liveLocalsOnBreak); return false; } - if (allInteger) { + // NOTE: it can still change in the tableswitch/lookupswitch case if there's no default case + // but we need to add a synthetic default case for local variable conversions + Label defaultLabel = defaultCase != null ? defaultCase.getEntry() : breakLabel; + final boolean hasSkipConversion = LocalVariableConversion.hasLiveConversion(switchNode); + + if (switchNode.isUniqueInteger()) { // Tree for sorting values. final TreeMap<Integer, Label> tree = new TreeMap<>(); @@ -1931,7 +2843,7 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex final Label entry = caseNode.getEntry(); // Take first duplicate. - if (!(tree.containsKey(value))) { + if (!tree.containsKey(value)) { tree.put(value, entry); } } @@ -1945,7 +2857,7 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex // Discern low, high and range. final int lo = values[0]; final int hi = values[size - 1]; - final int range = hi - lo + 1; + final long range = (long)hi - (long)lo + 1; // Find an unused value for default. int deflt = Integer.MIN_VALUE; @@ -1958,7 +2870,7 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex } // Load switch expression. - load(expression); + loadExpressionUnbounded(expression); final Type type = expression.getType(); // If expression not int see if we can convert, if not use deflt to trigger default. @@ -1968,11 +2880,15 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex method.invoke(staticCallNoLookup(ScriptRuntime.class, "switchTagAsInt", int.class, exprClass.isPrimitive()? exprClass : Object.class, int.class)); } - // If reasonable size and not too sparse (80%), use table otherwise use lookup. - if (range > 0 && range < 4096 && range < (size * 5 / 4)) { - final Label[] table = new Label[range]; + if(hasSkipConversion) { + assert defaultLabel == breakLabel; + defaultLabel = new Label("switch_skip"); + } + // TABLESWITCH needs (range + 3) 32-bit values; LOOKUPSWITCH needs ((size * 2) + 2). Choose the one with + // smaller representation, favor TABLESWITCH when they're equal size. + if (range + 1 <= (size * 2) && range <= Integer.MAX_VALUE) { + final Label[] table = new Label[(int)range]; Arrays.fill(table, defaultLabel); - for (int i = 0; i < size; i++) { final int value = values[i]; table[value - lo] = labels[i]; @@ -1987,97 +2903,163 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex method.lookupswitch(defaultLabel, ints, labels); } + // This is a synthetic "default case" used in absence of actual default case, created if we need to apply + // local variable conversions if neither case is taken. + if(hasSkipConversion) { + method.label(defaultLabel); + method.beforeJoinPoint(switchNode); + method._goto(breakLabel); + } } else { - load(expression, Type.OBJECT); - method.store(tag); + final Symbol tagSymbol = switchNode.getTag(); + // TODO: we could have non-object tag + final int tagSlot = tagSymbol.getSlot(Type.OBJECT); + loadExpressionAsObject(expression); + method.store(tagSymbol, Type.OBJECT); for (final CaseNode caseNode : cases) { final Expression test = caseNode.getTest(); if (test != null) { - method.load(tag); - load(test, Type.OBJECT); + method.load(Type.OBJECT, tagSlot); + loadExpressionAsObject(test); method.invoke(ScriptRuntime.EQ_STRICT); method.ifne(caseNode.getEntry()); } } - method._goto(hasDefault ? defaultLabel : breakLabel); + if (defaultCase != null) { + method._goto(defaultLabel); + } else { + method.beforeJoinPoint(switchNode); + method._goto(breakLabel); + } } + // First case is only reachable through jump + assert !method.isReachable(); + for (final CaseNode caseNode : cases) { + final Label fallThroughLabel; + if(caseNode.getLocalVariableConversion() != null && method.isReachable()) { + fallThroughLabel = new Label("fallthrough"); + method._goto(fallThroughLabel); + } else { + fallThroughLabel = null; + } method.label(caseNode.getEntry()); + method.beforeJoinPoint(caseNode); + if(fallThroughLabel != null) { + method.label(fallThroughLabel); + } caseNode.getBody().accept(this); } - if (!switchNode.isTerminal()) { - method.label(breakLabel); - } + method.breakLabel(breakLabel, liveLocalsOnBreak); return false; } @Override public boolean enterThrowNode(final ThrowNode throwNode) { - lineNumber(throwNode); + if(!method.isReachable()) { + return false; + } + enterStatement(throwNode); if (throwNode.isSyntheticRethrow()) { + method.beforeJoinPoint(throwNode); + //do not wrap whatever this is in an ecma exception, just rethrow it - load(throwNode.getExpression()); + final IdentNode exceptionExpr = (IdentNode)throwNode.getExpression(); + final Symbol exceptionSymbol = exceptionExpr.getSymbol(); + method.load(exceptionSymbol, EXCEPTION_TYPE); + method.checkcast(EXCEPTION_TYPE.getTypeClass()); method.athrow(); return false; } - final Source source = lc.getCurrentFunction().getSource(); - + final Source source = getCurrentSource(); final Expression expression = throwNode.getExpression(); final int position = throwNode.position(); final int line = throwNode.getLineNumber(); final int column = source.getColumn(position); - load(expression, Type.OBJECT); + // NOTE: we first evaluate the expression, and only after it was evaluated do we create the new ECMAException + // object and then somewhat cumbersomely move it beneath the evaluated expression on the stack. The reason for + // this is that if expression is optimistic (or contains an optimistic subexpression), we'd potentially access + // the not-yet-<init>ialized object on the stack from the UnwarrantedOptimismException handler, and bytecode + // verifier forbids that. + loadExpressionAsObject(expression); method.load(source.getName()); method.load(line); method.load(column); method.invoke(ECMAException.CREATE); + method.beforeJoinPoint(throwNode); method.athrow(); return false; } + private Source getCurrentSource() { + return lc.getCurrentFunction().getSource(); + } + @Override public boolean enterTryNode(final TryNode tryNode) { - lineNumber(tryNode); + if(!method.isReachable()) { + return false; + } + enterStatement(tryNode); final Block body = tryNode.getBody(); final List<Block> catchBlocks = tryNode.getCatchBlocks(); - final Symbol symbol = tryNode.getException(); + final Symbol vmException = tryNode.getException(); final Label entry = new Label("try"); final Label recovery = new Label("catch"); - final Label exit = tryNode.getExit(); + final Label exit = new Label("end_try"); final Label skip = new Label("skip"); + method.canThrow(recovery); + // Effect any conversions that might be observed at the entry of the catch node before entering the try node. + // This is because even the first instruction in the try block must be presumed to be able to transfer control + // to the catch block. Note that this doesn't kill the original values; in this regard it works a lot like + // conversions of assignments within the try block. + method.beforeTry(tryNode, recovery); method.label(entry); - - body.accept(this); - - if (!body.hasTerminalFlags()) { - method._goto(skip); + catchLabels.push(recovery); + try { + body.accept(this); + } finally { + assert catchLabels.peek() == recovery; + catchLabels.pop(); } method.label(exit); + final boolean bodyCanThrow = exit.isAfter(entry); + if(!bodyCanThrow) { + // The body can't throw an exception; don't even bother emitting the catch handlers, they're all dead code. + return false; + } + + method._try(entry, exit, recovery, Throwable.class); + if (method.isReachable()) { + method._goto(skip); + } method._catch(recovery); - method.store(symbol); + method.store(vmException, EXCEPTION_TYPE); - for (int i = 0; i < catchBlocks.size(); i++) { + final int catchBlockCount = catchBlocks.size(); + final Label afterCatch = new Label("after_catch"); + for (int i = 0; i < catchBlockCount; i++) { + assert method.isReachable(); final Block catchBlock = catchBlocks.get(i); - //TODO this is very ugly - try not to call enter/leave methods directly - //better to use the implicit lexical context scoping given by the visitor's - //accept method. + // Because of the peculiarities of the flow control, we need to use an explicit push/enterBlock/leaveBlock + // here. lc.push(catchBlock); enterBlock(catchBlock); @@ -2089,13 +3071,14 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex new Store<IdentNode>(exception) { @Override protected void storeNonDiscard() { - return; + // This expression is neither part of a discard, nor needs to be left on the stack after it was + // stored, so we override storeNonDiscard to be a no-op. } @Override protected void evaluate() { if (catchNode.isSyntheticRethrow()) { - method.load(symbol); + method.load(vmException, EXCEPTION_TYPE); return; } /* @@ -2104,126 +3087,273 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex * caught object itself to the script catch var. */ final Label notEcmaException = new Label("no_ecma_exception"); - method.load(symbol).dup()._instanceof(ECMAException.class).ifeq(notEcmaException); + method.load(vmException, EXCEPTION_TYPE).dup()._instanceof(ECMAException.class).ifeq(notEcmaException); method.checkcast(ECMAException.class); //TODO is this necessary? method.getField(ECMAException.THROWN); method.label(notEcmaException); } }.store(); - final Label next; - - if (exceptionCondition != null) { - next = new Label("next"); - load(exceptionCondition, Type.BOOLEAN).ifeq(next); + final boolean isConditionalCatch = exceptionCondition != null; + final Label nextCatch; + if (isConditionalCatch) { + loadExpressionAsBoolean(exceptionCondition); + nextCatch = new Label("next_catch"); + method.ifeq(nextCatch); } else { - next = null; + nextCatch = null; } catchBody.accept(this); - - if (i + 1 != catchBlocks.size() && !catchBody.hasTerminalFlags()) { - method._goto(skip); - } - - if (next != null) { - if (i + 1 == catchBlocks.size()) { - // no next catch block - rethrow if condition failed - method._goto(skip); - method.label(next); - method.load(symbol).athrow(); - } else { - method.label(next); - } - } - leaveBlock(catchBlock); lc.pop(catchBlock); + if(method.isReachable()) { + method._goto(afterCatch); + } + if(nextCatch != null) { + method.label(nextCatch); + } } + assert !method.isReachable(); + // afterCatch could be the same as skip, except that we need to establish that the vmException is dead. + method.label(afterCatch); + if(method.isReachable()) { + method.markDeadLocalVariable(vmException); + } method.label(skip); - method._try(entry, exit, recovery, Throwable.class); // Finally body is always inlined elsewhere so it doesn't need to be emitted - return false; } @Override public boolean enterVarNode(final VarNode varNode) { - - final Expression init = varNode.getInit(); - - if (init == null) { + if(!method.isReachable()) { return false; } - - lineNumber(varNode); - + final Expression init = varNode.getInit(); final IdentNode identNode = varNode.getName(); final Symbol identSymbol = identNode.getSymbol(); assert identSymbol != null : "variable node " + varNode + " requires a name with a symbol"; + final boolean needsScope = identSymbol.isScope(); + if (init == null) { + if (needsScope && varNode.isBlockScoped()) { + // block scoped variables need a DECLARE flag to signal end of temporal dead zone (TDZ) + method.loadCompilerConstant(SCOPE); + method.loadUndefined(Type.OBJECT); + final int flags = CALLSITE_SCOPE | getCallSiteFlags() | (varNode.isBlockScoped() ? CALLSITE_DECLARE : 0); + assert isFastScope(identSymbol); + storeFastScopeVar(identSymbol, flags); + } + return false; + } + + enterStatement(varNode); assert method != null; - final boolean needsScope = identSymbol.isScope(); if (needsScope) { method.loadCompilerConstant(SCOPE); } if (needsScope) { - load(init); - int flags = CALLSITE_SCOPE | getCallSiteFlags(); + loadExpressionUnbounded(init); + // block scoped variables need a DECLARE flag to signal end of temporal dead zone (TDZ) + final int flags = CALLSITE_SCOPE | getCallSiteFlags() | (varNode.isBlockScoped() ? CALLSITE_DECLARE : 0); if (isFastScope(identSymbol)) { storeFastScopeVar(identSymbol, flags); } else { - method.dynamicSet(identNode.getName(), flags); + method.dynamicSet(identNode.getName(), flags, false); } } else { - load(init, identNode.getType()); - method.store(identSymbol); + final Type identType = identNode.getType(); + if(identType == Type.UNDEFINED) { + // The initializer is either itself undefined (explicit assignment of undefined to undefined), + // or the left hand side is a dead variable. + assert init.getType() == Type.UNDEFINED || identNode.getSymbol().slotCount() == 0; + loadAndDiscard(init); + return false; + } + loadExpressionAsType(init, identType); + storeIdentWithCatchConversion(identNode, identType); } return false; } + private void storeIdentWithCatchConversion(final IdentNode identNode, final Type type) { + // Assignments happening in try/catch blocks need to ensure that they also store a possibly wider typed value + // that will be live at the exit from the try block + final LocalVariableConversion conversion = identNode.getLocalVariableConversion(); + final Symbol symbol = identNode.getSymbol(); + if(conversion != null && conversion.isLive()) { + assert symbol == conversion.getSymbol(); + assert symbol.isBytecodeLocal(); + // Only a single conversion from the target type to the join type is expected. + assert conversion.getNext() == null; + assert conversion.getFrom() == type; + // We must propagate potential type change to the catch block + final Label catchLabel = catchLabels.peek(); + assert catchLabel != METHOD_BOUNDARY; // ident conversion only exists in try blocks + assert catchLabel.isReachable(); + final Type joinType = conversion.getTo(); + final Label.Stack catchStack = catchLabel.getStack(); + final int joinSlot = symbol.getSlot(joinType); + // With nested try/catch blocks (incl. synthetic ones for finally), we can have a supposed conversion for + // the exception symbol in the nested catch, but it isn't live in the outer catch block, so prevent doing + // conversions for it. E.g. in "try { try { ... } catch(e) { e = 1; } } catch(e2) { ... }", we must not + // introduce an I->O conversion on "e = 1" assignment as "e" is not live in "catch(e2)". + if(catchStack.getUsedSlotsWithLiveTemporaries() > joinSlot) { + method.dup(); + method.convert(joinType); + method.store(symbol, joinType); + catchLabel.getStack().onLocalStore(joinType, joinSlot, true); + method.canThrow(catchLabel); + // Store but keep the previous store live too. + method.store(symbol, type, false); + return; + } + } + + method.store(symbol, type, true); + } + @Override public boolean enterWhileNode(final WhileNode whileNode) { - final Expression test = whileNode.getTest(); - final Block body = whileNode.getBody(); - final Label breakLabel = whileNode.getBreakLabel(); - final Label continueLabel = whileNode.getContinueLabel(); - final boolean isDoWhile = whileNode.isDoWhile(); - final Label loopLabel = new Label("loop"); - - if (!isDoWhile) { - method._goto(continueLabel); + if(!method.isReachable()) { + return false; } - - method.label(loopLabel); - body.accept(this); - if (!whileNode.isTerminal()) { - method.label(continueLabel); - lineNumber(whileNode); - new BranchOptimizer(this, method).execute(test, loopLabel, true); - method.label(breakLabel); + if(whileNode.isDoWhile()) { + enterDoWhile(whileNode); + } else { + enterStatement(whileNode); + enterForOrWhile(whileNode, null); } - return false; } - private void closeWith() { - if (method.hasScope()) { + private void enterForOrWhile(final LoopNode loopNode, final JoinPredecessorExpression modify) { + // NOTE: the usual pattern for compiling test-first loops is "GOTO test; body; test; IFNE body". We use the less + // conventional "test; IFEQ break; body; GOTO test; break;". It has one extra unconditional GOTO in each repeat + // of the loop, but it's not a problem for modern JIT compilers. We do this because our local variable type + // tracking is unfortunately not really prepared for out-of-order execution, e.g. compiling the following + // contrived but legal JavaScript code snippet would fail because the test changes the type of "i" from object + // to double: var i = {valueOf: function() { return 1} }; while(--i >= 0) { ... } + // Instead of adding more complexity to the local variable type tracking, we instead choose to emit this + // different code shape. + final int liveLocalsOnBreak = method.getUsedSlotsWithLiveTemporaries(); + final JoinPredecessorExpression test = loopNode.getTest(); + if(Expression.isAlwaysFalse(test)) { + loadAndDiscard(test); + return; + } + + method.beforeJoinPoint(loopNode); + + final Label continueLabel = loopNode.getContinueLabel(); + final Label repeatLabel = modify != null ? new Label("for_repeat") : continueLabel; + method.label(repeatLabel); + final int liveLocalsOnContinue = method.getUsedSlotsWithLiveTemporaries(); + + final Block body = loopNode.getBody(); + final Label breakLabel = loopNode.getBreakLabel(); + final boolean testHasLiveConversion = test != null && LocalVariableConversion.hasLiveConversion(test); + + if(Expression.isAlwaysTrue(test)) { + if(test != null) { + loadAndDiscard(test); + if(testHasLiveConversion) { + method.beforeJoinPoint(test); + } + } + } else if (test != null) { + if (testHasLiveConversion) { + emitBranch(test.getExpression(), body.getEntryLabel(), true); + method.beforeJoinPoint(test); + method._goto(breakLabel); + } else { + emitBranch(test.getExpression(), breakLabel, false); + } + } + + body.accept(this); + if(repeatLabel != continueLabel) { + emitContinueLabel(continueLabel, liveLocalsOnContinue); + } + + if (loopNode.hasPerIterationScope() && lc.getCurrentBlock().needsScope()) { + // ES6 for loops with LET init need a new scope for each iteration. We just create a shallow copy here. method.loadCompilerConstant(SCOPE); - method.invoke(ScriptRuntime.CLOSE_WITH); + method.invoke(virtualCallNoLookup(ScriptObject.class, "copy", ScriptObject.class)); method.storeCompilerConstant(SCOPE); } + + if(method.isReachable()) { + if(modify != null) { + lineNumber(loopNode); + loadAndDiscard(modify); + method.beforeJoinPoint(modify); + } + method._goto(repeatLabel); + } + + method.breakLabel(breakLabel, liveLocalsOnBreak); + } + + private void emitContinueLabel(final Label continueLabel, final int liveLocals) { + final boolean reachable = method.isReachable(); + method.breakLabel(continueLabel, liveLocals); + // If we reach here only through a continue statement (e.g. body does not exit normally) then the + // continueLabel can have extra non-temp symbols (e.g. exception from a try/catch contained in the body). We + // must make sure those are thrown away. + if(!reachable) { + method.undefineLocalVariables(lc.getUsedSlotCount(), false); + } } + private void enterDoWhile(final WhileNode whileNode) { + final int liveLocalsOnContinueOrBreak = method.getUsedSlotsWithLiveTemporaries(); + method.beforeJoinPoint(whileNode); + + final Block body = whileNode.getBody(); + body.accept(this); + + emitContinueLabel(whileNode.getContinueLabel(), liveLocalsOnContinueOrBreak); + if(method.isReachable()) { + lineNumber(whileNode); + final JoinPredecessorExpression test = whileNode.getTest(); + final Label bodyEntryLabel = body.getEntryLabel(); + final boolean testHasLiveConversion = LocalVariableConversion.hasLiveConversion(test); + if(Expression.isAlwaysFalse(test)) { + loadAndDiscard(test); + if(testHasLiveConversion) { + method.beforeJoinPoint(test); + } + } else if(testHasLiveConversion) { + // If we have conversions after the test in do-while, they need to be effected on both branches. + final Label beforeExit = new Label("do_while_preexit"); + emitBranch(test.getExpression(), beforeExit, false); + method.beforeJoinPoint(test); + method._goto(bodyEntryLabel); + method.label(beforeExit); + method.beforeJoinPoint(test); + } else { + emitBranch(test.getExpression(), bodyEntryLabel, true); + } + } + method.breakLabel(whileNode.getBreakLabel(), liveLocalsOnContinueOrBreak); + } + + @Override public boolean enterWithNode(final WithNode withNode) { + if(!method.isReachable()) { + return false; + } + enterStatement(withNode); final Expression expression = withNode.getExpression(); - final Node body = withNode.getBody(); + final Block body = withNode.getBody(); // It is possible to have a "pathological" case where the with block does not reference *any* identifiers. It's // pointless, but legal. In that case, if nothing else in the method forced the assignment of a slot to the @@ -2231,28 +3361,26 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex // for its side effect and visit the body, and not bother opening and closing a WithObject. final boolean hasScope = method.hasScope(); - final Label tryLabel; if (hasScope) { - tryLabel = new Label("with_try"); - method.label(tryLabel); method.loadCompilerConstant(SCOPE); - } else { - tryLabel = null; } - load(expression, Type.OBJECT); + loadExpressionAsObject(expression); + final Label tryLabel; if (hasScope) { // Construct a WithObject if we have a scope method.invoke(ScriptRuntime.OPEN_WITH); method.storeCompilerConstant(SCOPE); + tryLabel = new Label("with_try"); + method.label(tryLabel); } else { // We just loaded the expression for its side effect and to check // for null or undefined value. globalCheckObjectCoercible(); + tryLabel = null; } - // Always process body body.accept(this); @@ -2262,62 +3390,78 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex final Label catchLabel = new Label("with_catch"); final Label exitLabel = new Label("with_exit"); - if (!body.isTerminal()) { - closeWith(); - method._goto(exitLabel); - } - method.label(endLabel); + // Somewhat conservatively presume that if the body is not empty, it can throw an exception. In any case, + // we must prevent trying to emit a try-catch for empty range, as it causes a verification error. + final boolean bodyCanThrow = endLabel.isAfter(tryLabel); + if(bodyCanThrow) { + method._try(tryLabel, endLabel, catchLabel); + } - method._catch(catchLabel); - closeWith(); - method.athrow(); - - method.label(exitLabel); + final boolean reachable = method.isReachable(); + if(reachable) { + popScope(); + if(bodyCanThrow) { + method._goto(exitLabel); + } + } - method._try(tryLabel, endLabel, catchLabel); + if(bodyCanThrow) { + method._catch(catchLabel); + popScopeException(); + method.athrow(); + if(reachable) { + method.label(exitLabel); + } + } } return false; } - @Override - public boolean enterADD(final UnaryNode unaryNode) { - load(unaryNode.rhs(), unaryNode.getType()); - assert unaryNode.getType().isNumeric(); - method.store(unaryNode.getSymbol()); - return false; + private void loadADD(final UnaryNode unaryNode, final TypeBounds resultBounds) { + loadExpression(unaryNode.getExpression(), resultBounds.booleanToInt().notWiderThan(Type.NUMBER)); + if(method.peekType() == Type.BOOLEAN) { + // It's a no-op in bytecode, but we must make sure it is treated as an int for purposes of type signatures + method.convert(Type.INT); + } } - @Override - public boolean enterBIT_NOT(final UnaryNode unaryNode) { - load(unaryNode.rhs(), Type.INT).load(-1).xor().store(unaryNode.getSymbol()); - return false; + private void loadBIT_NOT(final UnaryNode unaryNode) { + loadExpression(unaryNode.getExpression(), TypeBounds.INT).load(-1).xor(); } - @Override - public boolean enterDECINC(final UnaryNode unaryNode) { - final Expression rhs = unaryNode.rhs(); + private void loadDECINC(final UnaryNode unaryNode) { + final Expression operand = unaryNode.getExpression(); final Type type = unaryNode.getType(); + final TypeBounds typeBounds = new TypeBounds(type, Type.NUMBER); final TokenType tokenType = unaryNode.tokenType(); final boolean isPostfix = tokenType == TokenType.DECPOSTFIX || tokenType == TokenType.INCPOSTFIX; final boolean isIncrement = tokenType == TokenType.INCPREFIX || tokenType == TokenType.INCPOSTFIX; assert !type.isObject(); - new SelfModifyingStore<UnaryNode>(unaryNode, rhs) { + new SelfModifyingStore<UnaryNode>(unaryNode, operand) { + + private void loadRhs() { + loadExpression(operand, typeBounds, true); + } @Override protected void evaluate() { - load(rhs, type, true); - if (!isPostfix) { - if (type.isInteger()) { - method.load(isIncrement ? 1 : -1); - } else if (type.isLong()) { - method.load(isIncrement ? 1L : -1L); - } else { - method.load(isIncrement ? 1.0 : -1.0); - } - method.add(); + if(isPostfix) { + loadRhs(); + } else { + new OptimisticOperation(unaryNode, typeBounds) { + @Override + void loadStack() { + loadRhs(); + loadMinusOne(); + } + @Override + void consumeStack() { + doDecInc(getProgramPoint()); + } + }.emit(getOptimisticIgnoreCountForSelfModifyingExpression(operand)); } } @@ -2325,448 +3469,485 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex protected void storeNonDiscard() { super.storeNonDiscard(); if (isPostfix) { - if (type.isInteger()) { - method.load(isIncrement ? 1 : -1); - } else if (type.isLong()) { - method.load(isIncrement ? 1L : 1L); - } else { - method.load(isIncrement ? 1.0 : -1.0); - } - method.add(); + new OptimisticOperation(unaryNode, typeBounds) { + @Override + void loadStack() { + loadMinusOne(); + } + @Override + void consumeStack() { + doDecInc(getProgramPoint()); + } + }.emit(1); // 1 for non-incremented result on the top of the stack pushed in evaluate() } } - }.store(); - return false; + private void loadMinusOne() { + if (type.isInteger()) { + method.load(isIncrement ? 1 : -1); + } else if (type.isLong()) { + method.load(isIncrement ? 1L : -1L); + } else { + method.load(isIncrement ? 1.0 : -1.0); + } + } + + private void doDecInc(final int programPoint) { + method.add(programPoint); + } + }.store(); } - @Override - public boolean enterDISCARD(final UnaryNode unaryNode) { - final Expression rhs = unaryNode.rhs(); + private static int getOptimisticIgnoreCountForSelfModifyingExpression(final Expression target) { + return target instanceof AccessNode ? 1 : target instanceof IndexNode ? 2 : 0; + } - lc.pushDiscard(rhs); - load(rhs); + private void loadAndDiscard(final Expression expr) { + // TODO: move checks for discarding to actual expression load code (e.g. as we do with void). That way we might + // be able to eliminate even more checks. + if(expr instanceof PrimitiveLiteralNode | isLocalVariable(expr)) { + assert lc.getCurrentDiscard() != expr; + // Don't bother evaluating expressions without side effects. Typical usage is "void 0" for reliably generating + // undefined. + return; + } - if (lc.getCurrentDiscard() == rhs) { - assert !rhs.isAssignment(); + lc.pushDiscard(expr); + loadExpression(expr, TypeBounds.UNBOUNDED); + if (lc.getCurrentDiscard() == expr) { + assert !expr.isAssignment(); + // NOTE: if we had a way to load with type void, we could avoid popping method.pop(); lc.popDiscard(); } - - return false; } - @Override - public boolean enterNEW(final UnaryNode unaryNode) { - final CallNode callNode = (CallNode)unaryNode.rhs(); + private void loadNEW(final UnaryNode unaryNode) { + final CallNode callNode = (CallNode)unaryNode.getExpression(); final List<Expression> args = callNode.getArgs(); // Load function reference. - load(callNode.getFunction(), Type.OBJECT); // must detect type error + loadExpressionAsObject(callNode.getFunction()); // must detect type error method.dynamicNew(1 + loadArgs(args), getCallSiteFlags()); - method.store(unaryNode.getSymbol()); - - return false; - } - - @Override - public boolean enterNOT(final UnaryNode unaryNode) { - final Expression rhs = unaryNode.rhs(); - - load(rhs, Type.BOOLEAN); - - final Label trueLabel = new Label("true"); - final Label afterLabel = new Label("after"); - - method.ifne(trueLabel); - method.load(true); - method._goto(afterLabel); - method.label(trueLabel); - method.load(false); - method.label(afterLabel); - method.store(unaryNode.getSymbol()); - - return false; - } - - @Override - public boolean enterSUB(final UnaryNode unaryNode) { - assert unaryNode.getType().isNumeric(); - load(unaryNode.rhs(), unaryNode.getType()).neg().store(unaryNode.getSymbol()); - return false; } - @Override - public boolean enterVOID(final UnaryNode unaryNode) { - load(unaryNode.rhs()).pop(); - method.loadUndefined(Type.OBJECT); + private void loadNOT(final UnaryNode unaryNode) { + final Expression expr = unaryNode.getExpression(); + if(expr instanceof UnaryNode && expr.isTokenType(TokenType.NOT)) { + // !!x is idiomatic boolean cast in JavaScript + loadExpressionAsBoolean(((UnaryNode)expr).getExpression()); + } else { + final Label trueLabel = new Label("true"); + final Label afterLabel = new Label("after"); - return false; + emitBranch(expr, trueLabel, true); + method.load(true); + method._goto(afterLabel); + method.label(trueLabel); + method.load(false); + method.label(afterLabel); + } } - private void enterNumericAdd(final Expression lhs, final Expression rhs, final Type type, final Symbol symbol) { - loadBinaryOperands(lhs, rhs, type); - method.add(); //if the symbol is optimistic, it always needs to be written, not on the stack? - method.store(symbol); + private void loadSUB(final UnaryNode unaryNode, final TypeBounds resultBounds) { + final Type type = unaryNode.getType(); + assert type.isNumeric(); + final TypeBounds numericBounds = resultBounds.booleanToInt(); + new OptimisticOperation(unaryNode, numericBounds) { + @Override + void loadStack() { + final Expression expr = unaryNode.getExpression(); + loadExpression(expr, numericBounds.notWiderThan(Type.NUMBER)); + } + @Override + void consumeStack() { + // Must do an explicit conversion to the operation's type when it's double so that we correctly handle + // negation of an int 0 to a double -0. With this, we get the correct negation of a local variable after + // it deoptimized, e.g. "iload_2; i2d; dneg". Without this, we get "iload_2; ineg; i2d". + if(type.isNumber()) { + method.convert(type); + } + method.neg(getProgramPoint()); + } + }.emit(); } - @Override - public boolean enterADD(final BinaryNode binaryNode) { - final Expression lhs = binaryNode.lhs(); - final Expression rhs = binaryNode.rhs(); - - final Type type = binaryNode.getType(); - if (type.isNumeric()) { - enterNumericAdd(lhs, rhs, type, binaryNode.getSymbol()); + public void loadVOID(final UnaryNode unaryNode, final TypeBounds resultBounds) { + loadAndDiscard(unaryNode.getExpression()); + if(lc.getCurrentDiscard() == unaryNode) { + lc.popDiscard(); } else { - loadBinaryOperands(binaryNode); - method.add(); - method.store(binaryNode.getSymbol()); + method.loadUndefined(resultBounds.widest); } + } - return false; + public void loadADD(final BinaryNode binaryNode, final TypeBounds resultBounds) { + new OptimisticOperation(binaryNode, resultBounds) { + @Override + void loadStack() { + final TypeBounds operandBounds; + final boolean isOptimistic = isValid(getProgramPoint()); + boolean forceConversionSeparation = false; + if(isOptimistic) { + operandBounds = new TypeBounds(binaryNode.getType(), Type.OBJECT); + } else { + // Non-optimistic, non-FP +. Allow it to overflow. + final Type widestOperationType = binaryNode.getWidestOperationType(); + operandBounds = new TypeBounds(Type.narrowest(binaryNode.getWidestOperandType(), resultBounds.widest), widestOperationType); + forceConversionSeparation = widestOperationType.narrowerThan(resultBounds.widest); + } + loadBinaryOperands(binaryNode.lhs(), binaryNode.rhs(), operandBounds, false, forceConversionSeparation); + } + + @Override + void consumeStack() { + method.add(getProgramPoint()); + } + }.emit(); } - private boolean enterAND_OR(final BinaryNode binaryNode) { - final Expression lhs = binaryNode.lhs(); - final Expression rhs = binaryNode.rhs(); + private void loadAND_OR(final BinaryNode binaryNode, final TypeBounds resultBounds, final boolean isAnd) { + final Type narrowestOperandType = Type.widestReturnType(binaryNode.lhs().getType(), binaryNode.rhs().getType()); final Label skip = new Label("skip"); + if(narrowestOperandType == Type.BOOLEAN) { + // optimize all-boolean logical expressions + final Label onTrue = new Label("andor_true"); + emitBranch(binaryNode, onTrue, true); + method.load(false); + method._goto(skip); + method.label(onTrue); + method.load(true); + method.label(skip); + return; + } - load(lhs, Type.OBJECT).dup().convert(Type.BOOLEAN); + final TypeBounds outBounds = resultBounds.notNarrowerThan(narrowestOperandType); + final JoinPredecessorExpression lhs = (JoinPredecessorExpression)binaryNode.lhs(); + final boolean lhsConvert = LocalVariableConversion.hasLiveConversion(lhs); + final Label evalRhs = lhsConvert ? new Label("eval_rhs") : null; - if (binaryNode.tokenType() == TokenType.AND) { - method.ifeq(skip); + loadExpression(lhs, outBounds).dup().convert(Type.BOOLEAN); + if (isAnd) { + if(lhsConvert) { + method.ifne(evalRhs); + } else { + method.ifeq(skip); + } + } else if(lhsConvert) { + method.ifeq(evalRhs); } else { method.ifne(skip); } + if(lhsConvert) { + method.beforeJoinPoint(lhs); + method._goto(skip); + method.label(evalRhs); + } + method.pop(); - load(rhs, Type.OBJECT); + final JoinPredecessorExpression rhs = (JoinPredecessorExpression)binaryNode.rhs(); + loadExpression(rhs, outBounds); + method.beforeJoinPoint(rhs); method.label(skip); - method.store(binaryNode.getSymbol()); + } - return false; + private static boolean isLocalVariable(final Expression lhs) { + return lhs instanceof IdentNode && isLocalVariable((IdentNode)lhs); } - @Override - public boolean enterAND(final BinaryNode binaryNode) { - return enterAND_OR(binaryNode); + private static boolean isLocalVariable(final IdentNode lhs) { + return lhs.getSymbol().isBytecodeLocal(); } - @Override - public boolean enterASSIGN(final BinaryNode binaryNode) { + // NOTE: does not use resultBounds as the assignment is driven by the type of the RHS + private void loadASSIGN(final BinaryNode binaryNode) { final Expression lhs = binaryNode.lhs(); final Expression rhs = binaryNode.rhs(); - final Type lhsType = lhs.getType(); final Type rhsType = rhs.getType(); - - if (!lhsType.isEquivalentTo(rhsType)) { - //this is OK if scoped, only locals are wrong + // Detect dead assignments + if(lhs instanceof IdentNode) { + final Symbol symbol = ((IdentNode)lhs).getSymbol(); + if(!symbol.isScope() && !symbol.hasSlotFor(rhsType) && lc.getCurrentDiscard() == binaryNode) { + loadAndDiscard(rhs); + lc.popDiscard(); + method.markDeadLocalVariable(symbol); + return; + } } new Store<BinaryNode>(binaryNode, lhs) { @Override protected void evaluate() { - if ((lhs instanceof IdentNode) && !lhs.getSymbol().isScope()) { - load(rhs, lhsType); - } else { - load(rhs); - } + // NOTE: we're loading with "at least as wide as" so optimistic operations on the right hand side + // remain optimistic, and then explicitly convert to the required type if needed. + loadExpressionAsType(rhs, rhsType); } }.store(); - - return false; } /** - * Helper class for assignment ops, e.g. *=, += and so on.. + * Binary self-assignment that can be optimistic: +=, -=, *=, and /=. */ - private abstract class AssignOp extends SelfModifyingStore<BinaryNode> { - - /** The type of the resulting operation */ - private final Type opType; + private abstract class BinaryOptimisticSelfAssignment extends SelfModifyingStore<BinaryNode> { /** * Constructor * * @param node the assign op node */ - AssignOp(final BinaryNode node) { - this(node.getType(), node); - } - - /** - * Constructor - * - * @param opType type of the computation - overriding the type of the node - * @param node the assign op node - */ - AssignOp(final Type opType, final BinaryNode node) { + BinaryOptimisticSelfAssignment(final BinaryNode node) { super(node, node.lhs()); - this.opType = opType; } - protected abstract void op(); + protected abstract void op(OptimisticOperation oo); @Override protected void evaluate() { - loadBinaryOperands(assignNode.lhs(), assignNode.rhs(), opType, true); - op(); + final Expression lhs = assignNode.lhs(); + final Expression rhs = assignNode.rhs(); + final Type widestOperationType = assignNode.getWidestOperationType(); + final TypeBounds bounds = new TypeBounds(assignNode.getType(), widestOperationType); + new OptimisticOperation(assignNode, bounds) { + @Override + void loadStack() { + final boolean forceConversionSeparation; + if (isValid(getProgramPoint()) || widestOperationType == Type.NUMBER) { + forceConversionSeparation = false; + } else { + final Type operandType = Type.widest(booleanToInt(objectToNumber(lhs.getType())), booleanToInt(objectToNumber(rhs.getType()))); + forceConversionSeparation = operandType.narrowerThan(widestOperationType); + } + loadBinaryOperands(lhs, rhs, bounds, true, forceConversionSeparation); + } + @Override + void consumeStack() { + op(this); + } + }.emit(getOptimisticIgnoreCountForSelfModifyingExpression(lhs)); method.convert(assignNode.getType()); } } - @Override - public boolean enterASSIGN_ADD(final BinaryNode binaryNode) { - assert RuntimeNode.Request.ADD.canSpecialize(); - final Type lhsType = binaryNode.lhs().getType(); - final Type rhsType = binaryNode.rhs().getType(); - final boolean specialize = binaryNode.getType() == Type.OBJECT; + /** + * Non-optimistic binary self-assignment operation. Basically, everything except +=, -=, *=, and /=. + */ + private abstract class BinarySelfAssignment extends SelfModifyingStore<BinaryNode> { + BinarySelfAssignment(final BinaryNode node) { + super(node, node.lhs()); + } - new AssignOp(binaryNode) { + protected abstract void op(); - @Override - protected void op() { - if (specialize) { - method.dynamicRuntimeCall( - new SpecializedRuntimeNode( - Request.ADD, - new Type[] { - lhsType, - rhsType, - }, - Type.OBJECT).getInitialName(), - Type.OBJECT, - Request.ADD); - } else { - method.add(); - } - } + @Override + protected void evaluate() { + loadBinaryOperands(assignNode.lhs(), assignNode.rhs(), TypeBounds.UNBOUNDED.notWiderThan(assignNode.getWidestOperandType()), true, false); + op(); + } + } + private void loadASSIGN_ADD(final BinaryNode binaryNode) { + new BinaryOptimisticSelfAssignment(binaryNode) { @Override - protected void evaluate() { - super.evaluate(); + protected void op(final OptimisticOperation oo) { + assert !(binaryNode.getType().isObject() && oo.isOptimistic); + method.add(oo.getProgramPoint()); } }.store(); - - return false; } - @Override - public boolean enterASSIGN_BIT_AND(final BinaryNode binaryNode) { - new AssignOp(Type.INT, binaryNode) { + private void loadASSIGN_BIT_AND(final BinaryNode binaryNode) { + new BinarySelfAssignment(binaryNode) { @Override protected void op() { method.and(); } }.store(); - - return false; } - @Override - public boolean enterASSIGN_BIT_OR(final BinaryNode binaryNode) { - new AssignOp(Type.INT, binaryNode) { + private void loadASSIGN_BIT_OR(final BinaryNode binaryNode) { + new BinarySelfAssignment(binaryNode) { @Override protected void op() { method.or(); } }.store(); - - return false; } - @Override - public boolean enterASSIGN_BIT_XOR(final BinaryNode binaryNode) { - new AssignOp(Type.INT, binaryNode) { + private void loadASSIGN_BIT_XOR(final BinaryNode binaryNode) { + new BinarySelfAssignment(binaryNode) { @Override protected void op() { method.xor(); } }.store(); - - return false; } - @Override - public boolean enterASSIGN_DIV(final BinaryNode binaryNode) { - new AssignOp(binaryNode) { + private void loadASSIGN_DIV(final BinaryNode binaryNode) { + new BinaryOptimisticSelfAssignment(binaryNode) { @Override - protected void op() { - method.div(); + protected void op(final OptimisticOperation oo) { + method.div(oo.getProgramPoint()); } }.store(); - - return false; } - @Override - public boolean enterASSIGN_MOD(final BinaryNode binaryNode) { - new AssignOp(binaryNode) { + private void loadASSIGN_MOD(final BinaryNode binaryNode) { + new BinaryOptimisticSelfAssignment(binaryNode) { @Override - protected void op() { - method.rem(); + protected void op(final OptimisticOperation oo) { + method.rem(oo.getProgramPoint()); } }.store(); - - return false; } - @Override - public boolean enterASSIGN_MUL(final BinaryNode binaryNode) { - new AssignOp(binaryNode) { + private void loadASSIGN_MUL(final BinaryNode binaryNode) { + new BinaryOptimisticSelfAssignment(binaryNode) { @Override - protected void op() { - method.mul(); + protected void op(final OptimisticOperation oo) { + method.mul(oo.getProgramPoint()); } }.store(); - - return false; } - @Override - public boolean enterASSIGN_SAR(final BinaryNode binaryNode) { - new AssignOp(Type.INT, binaryNode) { + private void loadASSIGN_SAR(final BinaryNode binaryNode) { + new BinarySelfAssignment(binaryNode) { @Override protected void op() { method.sar(); } }.store(); - - return false; } - @Override - public boolean enterASSIGN_SHL(final BinaryNode binaryNode) { - new AssignOp(Type.INT, binaryNode) { + private void loadASSIGN_SHL(final BinaryNode binaryNode) { + new BinarySelfAssignment(binaryNode) { @Override protected void op() { method.shl(); } }.store(); - - return false; } - @Override - public boolean enterASSIGN_SHR(final BinaryNode binaryNode) { - new AssignOp(Type.INT, binaryNode) { + private void loadASSIGN_SHR(final BinaryNode binaryNode) { + new BinarySelfAssignment(binaryNode) { @Override protected void op() { - method.shr(); - method.convert(Type.LONG).load(JSType.MAX_UINT).and(); + doSHR(); } + }.store(); + } - return false; + private void doSHR() { + // TODO: make SHR optimistic + method.shr(); + toUint(); } - @Override - public boolean enterASSIGN_SUB(final BinaryNode binaryNode) { - new AssignOp(binaryNode) { + private void toUint() { + JSType.TO_UINT32_I.invoke(method); + } + + private void loadASSIGN_SUB(final BinaryNode binaryNode) { + new BinaryOptimisticSelfAssignment(binaryNode) { @Override - protected void op() { - method.sub(); + protected void op(final OptimisticOperation oo) { + method.sub(oo.getProgramPoint()); } }.store(); - - return false; } /** * Helper class for binary arithmetic ops */ private abstract class BinaryArith { + protected abstract void op(int programPoint); - protected abstract void op(); + protected void evaluate(final BinaryNode node, final TypeBounds resultBounds) { + final TypeBounds numericBounds = resultBounds.booleanToInt().objectToNumber(); + new OptimisticOperation(node, numericBounds) { + @Override + void loadStack() { + final TypeBounds operandBounds; + boolean forceConversionSeparation = false; + if(numericBounds.narrowest == Type.NUMBER) { + // Result should be double always. Propagate it into the operands so we don't have lots of I2D + // and L2D after operand evaluation. + assert numericBounds.widest == Type.NUMBER; + operandBounds = numericBounds; + } else { + final boolean isOptimistic = isValid(getProgramPoint()); + if(isOptimistic || node.isTokenType(TokenType.DIV) || node.isTokenType(TokenType.MOD)) { + operandBounds = new TypeBounds(node.getType(), Type.NUMBER); + } else { + // Non-optimistic, non-FP subtraction or multiplication. Allow them to overflow. + operandBounds = new TypeBounds(Type.narrowest(node.getWidestOperandType(), + numericBounds.widest), Type.NUMBER); + forceConversionSeparation = node.getWidestOperationType().narrowerThan(numericBounds.widest); + } + } + loadBinaryOperands(node.lhs(), node.rhs(), operandBounds, false, forceConversionSeparation); + } - protected void evaluate(final BinaryNode node) { - loadBinaryOperands(node); - op(); - method.store(node.getSymbol()); + @Override + void consumeStack() { + op(getProgramPoint()); + } + }.emit(); } } - @Override - public boolean enterBIT_AND(final BinaryNode binaryNode) { - new BinaryArith() { - @Override - protected void op() { - method.and(); - } - }.evaluate(binaryNode); - - return false; + private void loadBIT_AND(final BinaryNode binaryNode) { + loadBinaryOperands(binaryNode); + method.and(); } - @Override - public boolean enterBIT_OR(final BinaryNode binaryNode) { - new BinaryArith() { - @Override - protected void op() { - method.or(); - } - }.evaluate(binaryNode); - - return false; - } - - @Override - public boolean enterBIT_XOR(final BinaryNode binaryNode) { - new BinaryArith() { - @Override - protected void op() { - method.xor(); - } - }.evaluate(binaryNode); - - return false; + private void loadBIT_OR(final BinaryNode binaryNode) { + // Optimize x|0 to (int)x + if (isRhsZero(binaryNode)) { + loadExpressionAsType(binaryNode.lhs(), Type.INT); + } else { + loadBinaryOperands(binaryNode); + method.or(); + } } - private boolean enterComma(final BinaryNode binaryNode) { - final Expression lhs = binaryNode.lhs(); + private static boolean isRhsZero(final BinaryNode binaryNode) { final Expression rhs = binaryNode.rhs(); + return rhs instanceof LiteralNode && INT_ZERO.equals(((LiteralNode<?>)rhs).getValue()); + } - load(lhs); - load(rhs); - method.store(binaryNode.getSymbol()); - - return false; + private void loadBIT_XOR(final BinaryNode binaryNode) { + loadBinaryOperands(binaryNode); + method.xor(); } - @Override - public boolean enterCOMMARIGHT(final BinaryNode binaryNode) { - return enterComma(binaryNode); + private void loadCOMMARIGHT(final BinaryNode binaryNode, final TypeBounds resultBounds) { + loadAndDiscard(binaryNode.lhs()); + loadExpression(binaryNode.rhs(), resultBounds); } - @Override - public boolean enterCOMMALEFT(final BinaryNode binaryNode) { - return enterComma(binaryNode); + private void loadCOMMALEFT(final BinaryNode binaryNode, final TypeBounds resultBounds) { + loadExpression(binaryNode.lhs(), resultBounds); + loadAndDiscard(binaryNode.rhs()); } - @Override - public boolean enterDIV(final BinaryNode binaryNode) { + private void loadDIV(final BinaryNode binaryNode, final TypeBounds resultBounds) { new BinaryArith() { @Override - protected void op() { - method.div(); + protected void op(final int programPoint) { + method.div(programPoint); } - }.evaluate(binaryNode); - - return false; + }.evaluate(binaryNode, resultBounds); } - private boolean enterCmp(final Expression lhs, final Expression rhs, final Condition cond, final Type type, final Symbol symbol) { - final Type lhsType = lhs.getType(); - final Type rhsType = rhs.getType(); + private void loadCmp(final BinaryNode binaryNode, final Condition cond) { + assert comparisonOperandsArePrimitive(binaryNode) : binaryNode; + loadBinaryOperands(binaryNode); - final Type widest = Type.widest(lhsType, rhsType); - assert widest.isNumeric() || widest.isBoolean() : widest; - - loadBinaryOperands(lhs, rhs, widest); final Label trueLabel = new Label("trueLabel"); final Label afterLabel = new Label("skip"); @@ -2777,177 +3958,100 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex method.label(trueLabel); method.load(Boolean.TRUE); method.label(afterLabel); - - method.convert(type); - method.store(symbol); - - return false; - } - - private boolean enterCmp(final BinaryNode binaryNode, final Condition cond) { - return enterCmp(binaryNode.lhs(), binaryNode.rhs(), cond, binaryNode.getType(), binaryNode.getSymbol()); - } - - @Override - public boolean enterEQ(final BinaryNode binaryNode) { - return enterCmp(binaryNode, Condition.EQ); - } - - @Override - public boolean enterEQ_STRICT(final BinaryNode binaryNode) { - return enterCmp(binaryNode, Condition.EQ); - } - - @Override - public boolean enterGE(final BinaryNode binaryNode) { - return enterCmp(binaryNode, Condition.GE); } - @Override - public boolean enterGT(final BinaryNode binaryNode) { - return enterCmp(binaryNode, Condition.GT); + private static boolean comparisonOperandsArePrimitive(final BinaryNode binaryNode) { + final Type widest = Type.widest(binaryNode.lhs().getType(), binaryNode.rhs().getType()); + return widest.isNumeric() || widest.isBoolean(); } - @Override - public boolean enterLE(final BinaryNode binaryNode) { - return enterCmp(binaryNode, Condition.LE); - } - - @Override - public boolean enterLT(final BinaryNode binaryNode) { - return enterCmp(binaryNode, Condition.LT); - } - - @Override - public boolean enterMOD(final BinaryNode binaryNode) { + private void loadMOD(final BinaryNode binaryNode, final TypeBounds resultBounds) { new BinaryArith() { @Override - protected void op() { - method.rem(); + protected void op(final int programPoint) { + method.rem(programPoint); } - }.evaluate(binaryNode); - - return false; + }.evaluate(binaryNode, resultBounds); } - @Override - public boolean enterMUL(final BinaryNode binaryNode) { + private void loadMUL(final BinaryNode binaryNode, final TypeBounds resultBounds) { new BinaryArith() { @Override - protected void op() { - method.mul(); + protected void op(final int programPoint) { + method.mul(programPoint); } - }.evaluate(binaryNode); - - return false; + }.evaluate(binaryNode, resultBounds); } - @Override - public boolean enterNE(final BinaryNode binaryNode) { - return enterCmp(binaryNode, Condition.NE); + private void loadSAR(final BinaryNode binaryNode) { + loadBinaryOperands(binaryNode); + method.sar(); } - @Override - public boolean enterNE_STRICT(final BinaryNode binaryNode) { - return enterCmp(binaryNode, Condition.NE); + private void loadSHL(final BinaryNode binaryNode) { + loadBinaryOperands(binaryNode); + method.shl(); } - @Override - public boolean enterOR(final BinaryNode binaryNode) { - return enterAND_OR(binaryNode); + private void loadSHR(final BinaryNode binaryNode) { + // Optimize x >>> 0 to (uint)x + if (isRhsZero(binaryNode)) { + loadExpressionAsType(binaryNode.lhs(), Type.INT); + toUint(); + } else { + loadBinaryOperands(binaryNode); + doSHR(); + } } - @Override - public boolean enterSAR(final BinaryNode binaryNode) { + private void loadSUB(final BinaryNode binaryNode, final TypeBounds resultBounds) { new BinaryArith() { @Override - protected void op() { - method.sar(); + protected void op(final int programPoint) { + method.sub(programPoint); } - }.evaluate(binaryNode); - - return false; + }.evaluate(binaryNode, resultBounds); } @Override - public boolean enterSHL(final BinaryNode binaryNode) { - new BinaryArith() { - @Override - protected void op() { - method.shl(); - } - }.evaluate(binaryNode); - - return false; + public boolean enterLabelNode(final LabelNode labelNode) { + labeledBlockBreakLiveLocals.push(lc.getUsedSlotCount()); + return true; } @Override - public boolean enterSHR(final BinaryNode binaryNode) { - new BinaryArith() { - @Override - protected void evaluate(final BinaryNode node) { - loadBinaryOperands(node.lhs(), node.rhs(), Type.INT); - op(); - method.store(node.getSymbol()); - } - @Override - protected void op() { - method.shr(); - method.convert(Type.LONG).load(JSType.MAX_UINT).and(); - } - }.evaluate(binaryNode); - - return false; + protected boolean enterDefault(final Node node) { + throw new AssertionError("Code generator entered node of type " + node.getClass().getName()); } - @Override - public boolean enterSUB(final BinaryNode binaryNode) { - new BinaryArith() { - @Override - protected void op() { - method.sub(); - } - }.evaluate(binaryNode); + private void loadTernaryNode(final TernaryNode ternaryNode, final TypeBounds resultBounds) { + final Expression test = ternaryNode.getTest(); + final JoinPredecessorExpression trueExpr = ternaryNode.getTrueExpression(); + final JoinPredecessorExpression falseExpr = ternaryNode.getFalseExpression(); - return false; - } + final Label falseLabel = new Label("ternary_false"); + final Label exitLabel = new Label("ternary_exit"); - @Override - public boolean enterTernaryNode(final TernaryNode ternaryNode) { - final Expression test = ternaryNode.getTest(); - final Expression trueExpr = ternaryNode.getTrueExpression(); - final Expression falseExpr = ternaryNode.getFalseExpression(); - - final Symbol symbol = ternaryNode.getSymbol(); - final Label falseLabel = new Label("ternary_false"); - final Label exitLabel = new Label("ternary_exit"); - - Type widest = Type.widest(ternaryNode.getType(), Type.widest(trueExpr.getType(), falseExpr.getType())); - if (trueExpr.getType().isArray() || falseExpr.getType().isArray()) { //loadArray creates a Java array type on the stack, calls global allocate, which creates a native array type - widest = Type.OBJECT; - } - - load(test, Type.BOOLEAN); - // we still keep the conversion here as the AccessSpecializer can have separated the types, e.g. var y = x ? x=55 : 17 - // will left as (Object)x=55 : (Object)17 by Lower. Then the first term can be {I}x=55 of type int, which breaks the - // symmetry for the temporary slot for this TernaryNode. This is evidence that we assign types and explicit conversions - // too early, or Apply the AccessSpecializer too late. We are mostly probably looking for a separate type pass to - // do this property. Then we never need any conversions in CodeGenerator - method.ifeq(falseLabel); - load(trueExpr, widest); + final Type outNarrowest = Type.narrowest(resultBounds.widest, Type.generic(Type.widestReturnType(trueExpr.getType(), falseExpr.getType()))); + final TypeBounds outBounds = resultBounds.notNarrowerThan(outNarrowest); + + emitBranch(test, falseLabel, false); + + loadExpression(trueExpr.getExpression(), outBounds); + assert Type.generic(method.peekType()) == outBounds.narrowest; + method.beforeJoinPoint(trueExpr); method._goto(exitLabel); method.label(falseLabel); - load(falseExpr, widest); + loadExpression(falseExpr.getExpression(), outBounds); + assert Type.generic(method.peekType()) == outBounds.narrowest; + method.beforeJoinPoint(falseExpr); method.label(exitLabel); - method.store(symbol); - - return false; } /** * Generate all shared scope calls generated during codegen. */ - protected void generateScopeCalls() { + void generateScopeCalls() { for (final SharedScopeCall scopeAccess : lc.getScopeCalls()) { scopeAccess.generateScopeCall(); } @@ -2957,20 +4061,18 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex * Debug code used to print symbols * * @param block the block we are in + * @param function the function we are in * @param ident identifier for block or function where applicable */ - @SuppressWarnings("resource") - private void printSymbols(final Block block, final String ident) { - if (!compiler.getEnv()._print_symbols) { - return; - } - - final PrintWriter out = compiler.getEnv().getErr(); - out.println("[BLOCK in '" + ident + "']"); - if (!block.printSymbols(out)) { - out.println("<no symbols>"); + private void printSymbols(final Block block, final FunctionNode function, final String ident) { + if (compiler.getScriptEnvironment()._print_symbols || function.getFlag(FunctionNode.IS_PRINT_SYMBOLS)) { + final PrintWriter out = compiler.getScriptEnvironment().getErr(); + out.println("[BLOCK in '" + ident + "']"); + if (!block.printSymbols(out)) { + out.println("<no symbols>"); + } + out.println(); } - out.println(); } @@ -3015,7 +4117,7 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex private int depth; /** If we have too many arguments, we need temporary storage, this is stored in 'quick' */ - private Symbol quick; + private IdentNode quick; /** * Constructor @@ -3046,9 +4148,6 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex } private void prologue() { - final Symbol targetSymbol = target.getSymbol(); - final Symbol scopeSymbol = lc.getCurrentFunction().compilerConstant(SCOPE); - /** * This loads the parts of the target, e.g base and index. they are kept * on the stack throughout the store and used at the end to execute it @@ -3057,9 +4156,10 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex target.accept(new NodeVisitor<LexicalContext>(new LexicalContext()) { @Override public boolean enterIdentNode(final IdentNode node) { - if (targetSymbol.isScope()) { - method.load(scopeSymbol); - depth++; + if (node.getSymbol().isScope()) { + method.loadCompilerConstant(SCOPE); + depth += Type.SCOPE.getSlots(); + assert depth == 1; } return false; } @@ -3069,8 +4169,9 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex final BaseNode baseNode = (BaseNode)target; final Expression base = baseNode.getBase(); - load(base, Type.OBJECT); + loadExpressionAsObject(base); depth += Type.OBJECT.getSlots(); + assert depth == 1; if (isSelfModifying()) { method.dup(); @@ -3090,9 +4191,9 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex final Expression index = node.getIndex(); if (!index.getType().isNumeric()) { // could be boolean here as well - load(index, Type.OBJECT); + loadExpressionAsObject(index); } else { - load(index); + loadExpressionUnbounded(index); } depth += index.getType().getSlots(); @@ -3107,28 +4208,23 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex }); } - private Symbol quickSymbol(final Type type) { - return quickSymbol(type, QUICK_PREFIX.symbolName()); - } - /** - * Quick symbol generates an extra local variable, always using the same - * slot, one that is available after the end of the frame. + * Generates an extra local variable, always using the same slot, one that is available after the end of the + * frame. * - * @param type the type of the symbol - * @param prefix the prefix for the variable name for the symbol + * @param type the type of the variable * - * @return the quick symbol + * @return the quick variable */ - private Symbol quickSymbol(final Type type, final String prefix) { - final String name = lc.getCurrentFunction().uniqueName(prefix); - final Symbol symbol = new Symbol(name, IS_TEMP | IS_INTERNAL); - - symbol.setType(type); + private IdentNode quickLocalVariable(final Type type) { + final String name = lc.getCurrentFunction().uniqueName(QUICK_PREFIX.symbolName()); + final Symbol symbol = new Symbol(name, IS_INTERNAL | HAS_SLOT); + symbol.setHasSlotFor(type); + symbol.setFirstSlot(lc.quickSlot(type)); - symbol.setSlot(lc.quickSlot(symbol)); + final IdentNode quickIdent = IdentNode.createInternalIdentifier(symbol).setType(type); - return symbol; + return quickIdent; } // store the result that "lives on" after the op, e.g. "i" in i++ postfix. @@ -3139,16 +4235,12 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex return; } - final Symbol symbol = assignNode.getSymbol(); - if (symbol.hasSlot()) { - method.dup().store(symbol); - return; - } - if (method.dup(depth) == null) { method.dup(); - this.quick = quickSymbol(method.peekType()); - method.store(quick); + final Type quickType = method.peekType(); + this.quick = quickLocalVariable(quickType); + final Symbol quickSymbol = quick.getSymbol(); + method.storeTemp(quickType, quickSymbol.getFirstSlot()); } } @@ -3163,7 +4255,7 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex */ target.accept(new NodeVisitor<LexicalContext>(new LexicalContext()) { @Override - protected boolean enterDefault(Node node) { + protected boolean enterDefault(final Node node) { throw new AssertionError("Unexpected node " + node + " in store epilogue"); } @@ -3172,14 +4264,20 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex final Symbol symbol = node.getSymbol(); assert symbol != null; if (symbol.isScope()) { + final int flags = CALLSITE_SCOPE | getCallSiteFlags(); if (isFastScope(symbol)) { - storeFastScopeVar(symbol, CALLSITE_SCOPE | getCallSiteFlags()); + storeFastScopeVar(symbol, flags); } else { - method.dynamicSet(node.getName(), CALLSITE_SCOPE | getCallSiteFlags()); + method.dynamicSet(node.getName(), flags, false); } } else { - method.convert(node.getType()); - method.store(symbol); + final Type storeType = assignNode.getType(); + if (symbol.hasSlotFor(storeType)) { + // Only emit a convert for a store known to be live; converts for dead stores can + // give us an unnecessary ClassCastException. + method.convert(storeType); + } + storeIdentWithCatchConversion(node, storeType); } return false; @@ -3187,7 +4285,7 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex @Override public boolean enterAccessNode(final AccessNode node) { - method.dynamicSet(node.getProperty().getName(), getCallSiteFlags()); + method.dynamicSet(node.getProperty(), getCallSiteFlags(), node.isIndex()); return false; } @@ -3205,6 +4303,9 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex protected abstract void evaluate(); void store() { + if (target instanceof IdentNode) { + checkTemporalDeadZone((IdentNode)target); + } prologue(); evaluate(); // leaves an operation of whatever the operationType was on the stack storeNonDiscard(); @@ -3215,35 +4316,44 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex } } - private void newFunctionObject(final FunctionNode functionNode, final FunctionNode originalFunctionNode) { + private void newFunctionObject(final FunctionNode functionNode, final boolean addInitializer) { assert lc.peek() == functionNode; - // We don't emit a ScriptFunction on stack for: - // 1. the outermost compiled function (as there's no code being generated in its outer context that'd need it - // as a callee), and - // 2. for functions that are immediately called upon definition and they don't need a callee, e.g. (function(){})(). - // Such immediately-called functions are invoked using INVOKESTATIC (see enterFunctionNode() of the embedded - // visitor of enterCallNode() for details), and if they don't need a callee, they don't have it on their - // static method's parameter list. - if (lc.getOutermostFunction() == functionNode || - (!functionNode.needsCallee()) && lc.isFunctionDefinedInCurrentCall(originalFunctionNode)) { - return; + + final RecompilableScriptFunctionData data = compiler.getScriptFunctionData(functionNode.getId()); + + if (functionNode.isProgram() && !compiler.isOnDemandCompilation()) { + final CompileUnit fnUnit = functionNode.getCompileUnit(); + final MethodEmitter createFunction = fnUnit.getClassEmitter().method( + EnumSet.of(Flag.PUBLIC, Flag.STATIC), CREATE_PROGRAM_FUNCTION.symbolName(), + ScriptFunction.class, ScriptObject.class); + createFunction.begin(); + createFunction._new(SCRIPTFUNCTION_IMPL_NAME, SCRIPTFUNCTION_IMPL_TYPE).dup(); + loadConstant(data, fnUnit, createFunction); + createFunction.load(SCOPE_TYPE, 0); + createFunction.invoke(constructorNoLookup(SCRIPTFUNCTION_IMPL_NAME, RecompilableScriptFunctionData.class, ScriptObject.class)); + createFunction._return(); + createFunction.end(); } - // Generate the object class and property map in case this function is ever used as constructor - final String className = SCRIPTFUNCTION_IMPL_OBJECT; - final int fieldCount = ObjectClassGenerator.getPaddedFieldCount(functionNode.countThisProperties()); - final String allocatorClassName = Compiler.binaryName(ObjectClassGenerator.getClassName(fieldCount)); - final PropertyMap allocatorMap = PropertyMap.newMap(null, allocatorClassName, 0, fieldCount, 0); + if (addInitializer && !compiler.isOnDemandCompilation()) { + compiler.addFunctionInitializer(data, functionNode); + } - method._new(className).dup(); - loadConstant(new RecompilableScriptFunctionData(functionNode, compiler.getCodeInstaller(), allocatorClassName, allocatorMap)); + // We don't emit a ScriptFunction on stack for the outermost compiled function (as there's no code being + // generated in its outer context that'd need it as a callee). + if (lc.getOutermostFunction() == functionNode) { + return; + } + + method._new(SCRIPTFUNCTION_IMPL_NAME, SCRIPTFUNCTION_IMPL_TYPE).dup(); + loadConstant(data); - if (functionNode.isLazy() || functionNode.needsParentScope()) { + if (functionNode.needsParentScope()) { method.loadCompilerConstant(SCOPE); } else { method.loadNull(); } - method.invoke(constructorNoLookup(className, RecompilableScriptFunctionData.class, ScriptObject.class)); + method.invoke(constructorNoLookup(SCRIPTFUNCTION_IMPL_NAME, RecompilableScriptFunctionData.class, ScriptObject.class)); } // calls on Global class. @@ -3251,10 +4361,6 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex return method.invokestatic(GLOBAL_OBJECT, "instance", "()L" + GLOBAL_OBJECT + ';'); } - private MethodEmitter globalObjectPrototype() { - return method.invokestatic(GLOBAL_OBJECT, "objectPrototype", methodDescriptor(ScriptObject.class)); - } - private MethodEmitter globalAllocateArguments() { return method.invokestatic(GLOBAL_OBJECT, "allocateArguments", methodDescriptor(ScriptObject.class, Object[].class, Object.class, int.class)); } @@ -3276,12 +4382,907 @@ final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContex return method.invokestatic(GLOBAL_OBJECT, "isEval", methodDescriptor(boolean.class, Object.class)); } + private MethodEmitter globalReplaceLocationPropertyPlaceholder() { + return method.invokestatic(GLOBAL_OBJECT, "replaceLocationPropertyPlaceholder", methodDescriptor(Object.class, Object.class, Object.class)); + } + private MethodEmitter globalCheckObjectCoercible() { return method.invokestatic(GLOBAL_OBJECT, "checkObjectCoercible", methodDescriptor(void.class, Object.class)); } private MethodEmitter globalDirectEval() { return method.invokestatic(GLOBAL_OBJECT, "directEval", - methodDescriptor(Object.class, Object.class, Object.class, Object.class, Object.class, Object.class)); + methodDescriptor(Object.class, Object.class, Object.class, Object.class, Object.class, boolean.class)); + } + + private abstract class OptimisticOperation { + private final boolean isOptimistic; + // expression and optimistic are the same reference + private final Expression expression; + private final Optimistic optimistic; + private final TypeBounds resultBounds; + + OptimisticOperation(final Optimistic optimistic, final TypeBounds resultBounds) { + this.optimistic = optimistic; + this.expression = (Expression)optimistic; + this.resultBounds = resultBounds; + this.isOptimistic = isOptimistic(optimistic) && useOptimisticTypes() && + // Operation is only effectively optimistic if its type, after being coerced into the result bounds + // is narrower than the upper bound. + resultBounds.within(Type.generic(((Expression)optimistic).getType())).narrowerThan(resultBounds.widest); + } + + MethodEmitter emit() { + return emit(0); + } + + MethodEmitter emit(final int ignoredArgCount) { + final int programPoint = optimistic.getProgramPoint(); + final boolean optimisticOrContinuation = isOptimistic || isContinuationEntryPoint(programPoint); + final boolean currentContinuationEntryPoint = isCurrentContinuationEntryPoint(programPoint); + final int stackSizeOnEntry = method.getStackSize() - ignoredArgCount; + + // First store the values on the stack opportunistically into local variables. Doing it before loadStack() + // allows us to not have to pop/load any arguments that are pushed onto it by loadStack() in the second + // storeStack(). + storeStack(ignoredArgCount, optimisticOrContinuation); + + // Now, load the stack + loadStack(); + + // Now store the values on the stack ultimately into local variables. In vast majority of cases, this is + // (aside from creating the local types map) a no-op, as the first opportunistic stack store will already + // store all variables. However, there can be operations in the loadStack() that invalidate some of the + // stack stores, e.g. in "x[i] = x[++i]", "++i" will invalidate the already stored value for "i". In such + // unfortunate cases this second storeStack() will restore the invariant that everything on the stack is + // stored into a local variable, although at the cost of doing a store/load on the loaded arguments as well. + final int liveLocalsCount = storeStack(method.getStackSize() - stackSizeOnEntry, optimisticOrContinuation); + assert optimisticOrContinuation == (liveLocalsCount != -1); + + final Label beginTry; + final Label catchLabel; + final Label afterConsumeStack = isOptimistic || currentContinuationEntryPoint ? new Label("after_consume_stack") : null; + if(isOptimistic) { + beginTry = new Label("try_optimistic"); + final String catchLabelName = (afterConsumeStack == null ? "" : afterConsumeStack.toString()) + "_handler"; + catchLabel = new Label(catchLabelName); + method.label(beginTry); + } else { + beginTry = catchLabel = null; + } + + consumeStack(); + + if(isOptimistic) { + method._try(beginTry, afterConsumeStack, catchLabel, UnwarrantedOptimismException.class); + } + + if(isOptimistic || currentContinuationEntryPoint) { + method.label(afterConsumeStack); + + final int[] localLoads = method.getLocalLoadsOnStack(0, stackSizeOnEntry); + assert everyStackValueIsLocalLoad(localLoads) : Arrays.toString(localLoads) + ", " + stackSizeOnEntry + ", " + ignoredArgCount; + final List<Type> localTypesList = method.getLocalVariableTypes(); + final int usedLocals = method.getUsedSlotsWithLiveTemporaries(); + final List<Type> localTypes = method.getWidestLiveLocals(localTypesList.subList(0, usedLocals)); + assert everyLocalLoadIsValid(localLoads, usedLocals) : Arrays.toString(localLoads) + " ~ " + localTypes; + + if(isOptimistic) { + addUnwarrantedOptimismHandlerLabel(localTypes, catchLabel); + } + if(currentContinuationEntryPoint) { + final ContinuationInfo ci = getContinuationInfo(); + assert ci != null : "no continuation info found for " + lc.getCurrentFunction(); + assert !ci.hasTargetLabel(); // No duplicate program points + ci.setTargetLabel(afterConsumeStack); + ci.getHandlerLabel().markAsOptimisticContinuationHandlerFor(afterConsumeStack); + // Can't rely on targetLabel.stack.localVariableTypes.length, as it can be higher due to effectively + // dead local variables. + ci.lvarCount = localTypes.size(); + ci.setStackStoreSpec(localLoads); + ci.setStackTypes(Arrays.copyOf(method.getTypesFromStack(method.getStackSize()), stackSizeOnEntry)); + assert ci.getStackStoreSpec().length == ci.getStackTypes().length; + ci.setReturnValueType(method.peekType()); + ci.lineNumber = getLastLineNumber(); + ci.catchLabel = catchLabels.peek(); + } + } + return method; + } + + /** + * Stores the current contents of the stack into local variables so they are not lost before invoking something that + * can result in an {@code UnwarantedOptimizationException}. + * @param ignoreArgCount the number of topmost arguments on stack to ignore when deciding on the shape of the catch + * block. Those are used in the situations when we could not place the call to {@code storeStack} early enough + * (before emitting code for pushing the arguments that the optimistic call will pop). This is admittedly a + * deficiency in the design of the code generator when it deals with self-assignments and we should probably look + * into fixing it. + * @return types of the significant local variables after the stack was stored (types for local variables used + * for temporary storage of ignored arguments are not returned). + * @param optimisticOrContinuation if false, this method should not execute + * a label for a catch block for the {@code UnwarantedOptimizationException}, suitable for capturing the + * currently live local variables, tailored to their types. + */ + private int storeStack(final int ignoreArgCount, final boolean optimisticOrContinuation) { + if(!optimisticOrContinuation) { + return -1; // NOTE: correct value to return is lc.getUsedSlotCount(), but it wouldn't be used anyway + } + + final int stackSize = method.getStackSize(); + final Type[] stackTypes = method.getTypesFromStack(stackSize); + final int[] localLoadsOnStack = method.getLocalLoadsOnStack(0, stackSize); + final int usedSlots = method.getUsedSlotsWithLiveTemporaries(); + + final int firstIgnored = stackSize - ignoreArgCount; + // Find the first value on the stack (from the bottom) that is not a load from a local variable. + int firstNonLoad = 0; + while(firstNonLoad < firstIgnored && localLoadsOnStack[firstNonLoad] != Label.Stack.NON_LOAD) { + firstNonLoad++; + } + + // Only do the store/load if first non-load is not an ignored argument. Otherwise, do nothing and return + // the number of used slots as the number of live local variables. + if(firstNonLoad >= firstIgnored) { + return usedSlots; + } + + // Find the number of new temporary local variables that we need; it's the number of values on the stack that + // are not direct loads of existing local variables. + int tempSlotsNeeded = 0; + for(int i = firstNonLoad; i < stackSize; ++i) { + if(localLoadsOnStack[i] == Label.Stack.NON_LOAD) { + tempSlotsNeeded += stackTypes[i].getSlots(); + } + } + + // Ensure all values on the stack that weren't directly loaded from a local variable are stored in a local + // variable. We're starting from highest local variable index, so that in case ignoreArgCount > 0 the ignored + // ones end up at the end of the local variable table. + int lastTempSlot = usedSlots + tempSlotsNeeded; + int ignoreSlotCount = 0; + for(int i = stackSize; i -- > firstNonLoad;) { + final int loadSlot = localLoadsOnStack[i]; + if(loadSlot == Label.Stack.NON_LOAD) { + final Type type = stackTypes[i]; + final int slots = type.getSlots(); + lastTempSlot -= slots; + if(i >= firstIgnored) { + ignoreSlotCount += slots; + } + method.storeTemp(type, lastTempSlot); + } else { + method.pop(); + } + } + assert lastTempSlot == usedSlots; // used all temporary locals + + final List<Type> localTypesList = method.getLocalVariableTypes(); + + // Load values back on stack. + for(int i = firstNonLoad; i < stackSize; ++i) { + final int loadSlot = localLoadsOnStack[i]; + final Type stackType = stackTypes[i]; + final boolean isLoad = loadSlot != Label.Stack.NON_LOAD; + final int lvarSlot = isLoad ? loadSlot : lastTempSlot; + final Type lvarType = localTypesList.get(lvarSlot); + method.load(lvarType, lvarSlot); + if(isLoad) { + // Conversion operators (I2L etc.) preserve "load"-ness of the value despite the fact that, in the + // strict sense they are creating a derived value from the loaded value. This special behavior of + // on-stack conversion operators is necessary to accommodate for differences in local variable types + // after deoptimization; having a conversion operator throw away "load"-ness would create different + // local variable table shapes between optimism-failed code and its deoptimized rest-of method). + // After we load the value back, we need to redo the conversion to the stack type if stack type is + // different. + // NOTE: this would only strictly be necessary for widening conversions (I2L, L2D, I2D), and not for + // narrowing ones (L2I, D2L, D2I) as only widening conversions are the ones that can get eliminated + // in a deoptimized method, as their original input argument got widened. Maybe experiment with + // throwing away "load"-ness for narrowing conversions in MethodEmitter.convert()? + method.convert(stackType); + } else { + // temporary stores never needs a convert, as their type is always the same as the stack type. + assert lvarType == stackType; + lastTempSlot += lvarType.getSlots(); + } + } + // used all temporaries + assert lastTempSlot == usedSlots + tempSlotsNeeded; + + return lastTempSlot - ignoreSlotCount; + } + + private void addUnwarrantedOptimismHandlerLabel(final List<Type> localTypes, final Label label) { + final String lvarTypesDescriptor = getLvarTypesDescriptor(localTypes); + final Map<String, Collection<Label>> unwarrantedOptimismHandlers = lc.getUnwarrantedOptimismHandlers(); + Collection<Label> labels = unwarrantedOptimismHandlers.get(lvarTypesDescriptor); + if(labels == null) { + labels = new LinkedList<>(); + unwarrantedOptimismHandlers.put(lvarTypesDescriptor, labels); + } + method.markLabelAsOptimisticCatchHandler(label, localTypes.size()); + labels.add(label); + } + + abstract void loadStack(); + + // Make sure that whatever indy call site you emit from this method uses {@code getCallSiteFlagsOptimistic(node)} + // or otherwise ensure optimistic flag is correctly set in the call site, otherwise it doesn't make much sense + // to use OptimisticExpression for emitting it. + abstract void consumeStack(); + + /** + * Emits the correct dynamic getter code. Normally just delegates to method emitter, except when the target + * expression is optimistic, and the desired type is narrower than the optimistic type. In that case, it'll emit a + * dynamic getter with its original optimistic type, and explicitly insert a narrowing conversion. This way we can + * preserve the optimism of the values even if they're subsequently immediately coerced into a narrower type. This + * is beneficial because in this case we can still presume that since the original getter was optimistic, the + * conversion has no side effects. + * @param name the name of the property being get + * @param flags call site flags + * @param isMethod whether we're preferrably retrieving a function + * @return the current method emitter + */ + MethodEmitter dynamicGet(final String name, final int flags, final boolean isMethod, final boolean isIndex) { + if(isOptimistic) { + return method.dynamicGet(getOptimisticCoercedType(), name, getOptimisticFlags(flags), isMethod, isIndex); + } + return method.dynamicGet(resultBounds.within(expression.getType()), name, nonOptimisticFlags(flags), isMethod, isIndex); + } + + MethodEmitter dynamicGetIndex(final int flags, final boolean isMethod) { + if(isOptimistic) { + return method.dynamicGetIndex(getOptimisticCoercedType(), getOptimisticFlags(flags), isMethod); + } + return method.dynamicGetIndex(resultBounds.within(expression.getType()), nonOptimisticFlags(flags), isMethod); + } + + MethodEmitter dynamicCall(final int argCount, final int flags) { + if (isOptimistic) { + return method.dynamicCall(getOptimisticCoercedType(), argCount, getOptimisticFlags(flags)); + } + return method.dynamicCall(resultBounds.within(expression.getType()), argCount, nonOptimisticFlags(flags)); + } + + int getOptimisticFlags(final int flags) { + return flags | CALLSITE_OPTIMISTIC | (optimistic.getProgramPoint() << CALLSITE_PROGRAM_POINT_SHIFT); //encode program point in high bits + } + + int getProgramPoint() { + return isOptimistic ? optimistic.getProgramPoint() : INVALID_PROGRAM_POINT; + } + + void convertOptimisticReturnValue() { + if (isOptimistic) { + final Type optimisticType = getOptimisticCoercedType(); + if(!optimisticType.isObject()) { + method.load(optimistic.getProgramPoint()); + if(optimisticType.isInteger()) { + method.invoke(ENSURE_INT); + } else if(optimisticType.isLong()) { + method.invoke(ENSURE_LONG); + } else if(optimisticType.isNumber()) { + method.invoke(ENSURE_NUMBER); + } else { + throw new AssertionError(optimisticType); + } + } + } + } + + void replaceCompileTimeProperty() { + final IdentNode identNode = (IdentNode)expression; + final String name = identNode.getSymbol().getName(); + if (CompilerConstants.__FILE__.name().equals(name)) { + replaceCompileTimeProperty(getCurrentSource().getName()); + } else if (CompilerConstants.__DIR__.name().equals(name)) { + replaceCompileTimeProperty(getCurrentSource().getBase()); + } else if (CompilerConstants.__LINE__.name().equals(name)) { + replaceCompileTimeProperty(getCurrentSource().getLine(identNode.position())); + } + } + + /** + * When an ident with name __FILE__, __DIR__, or __LINE__ is loaded, we'll try to look it up as any other + * identifier. However, if it gets all the way up to the Global object, it will send back a special value that + * represents a placeholder for these compile-time location properties. This method will generate code that loads + * the value of the compile-time location property and then invokes a method in Global that will replace the + * placeholder with the value. Effectively, if the symbol for these properties is defined anywhere in the lexical + * scope, they take precedence, but if they aren't, then they resolve to the compile-time location property. + * @param propertyValue the actual value of the property + */ + private void replaceCompileTimeProperty(final Object propertyValue) { + assert method.peekType().isObject(); + if(propertyValue instanceof String || propertyValue == null) { + method.load((String)propertyValue); + } else if(propertyValue instanceof Integer) { + method.load(((Integer)propertyValue).intValue()); + method.convert(Type.OBJECT); + } else { + throw new AssertionError(); + } + globalReplaceLocationPropertyPlaceholder(); + convertOptimisticReturnValue(); + } + + /** + * Returns the type that should be used as the return type of the dynamic invocation that is emitted as the code + * for the current optimistic operation. If the type bounds is exact boolean or narrower than the expression's + * optimistic type, then the optimistic type is returned, otherwise the coercing type. Effectively, this method + * allows for moving the coercion into the optimistic type when it won't adversely affect the optimistic + * evaluation semantics, and for preserving the optimistic type and doing a separate coercion when it would + * affect it. + * @return + */ + private Type getOptimisticCoercedType() { + final Type optimisticType = expression.getType(); + assert resultBounds.widest.widerThan(optimisticType); + final Type narrowest = resultBounds.narrowest; + + if(narrowest.isBoolean() || narrowest.narrowerThan(optimisticType)) { + assert !optimisticType.isObject(); + return optimisticType; + } + assert !narrowest.isObject(); + return narrowest; + } + } + + private static boolean isOptimistic(final Optimistic optimistic) { + if(!optimistic.canBeOptimistic()) { + return false; + } + final Expression expr = (Expression)optimistic; + return expr.getType().narrowerThan(expr.getWidestOperationType()); + } + + private static boolean everyLocalLoadIsValid(final int[] loads, final int localCount) { + for (final int load : loads) { + if(load < 0 || load >= localCount) { + return false; + } + } + return true; + } + + private static boolean everyStackValueIsLocalLoad(final int[] loads) { + for (final int load : loads) { + if(load == Label.Stack.NON_LOAD) { + return false; + } + } + return true; + } + + private String getLvarTypesDescriptor(final List<Type> localVarTypes) { + final int count = localVarTypes.size(); + final StringBuilder desc = new StringBuilder(count); + for(int i = 0; i < count;) { + i += appendType(desc, localVarTypes.get(i)); + } + return method.markSymbolBoundariesInLvarTypesDescriptor(desc.toString()); + } + + private static int appendType(final StringBuilder b, final Type t) { + b.append(t.getBytecodeStackType()); + return t.getSlots(); + } + + private static int countSymbolsInLvarTypeDescriptor(final String lvarTypeDescriptor) { + int count = 0; + for(int i = 0; i < lvarTypeDescriptor.length(); ++i) { + if(Character.isUpperCase(lvarTypeDescriptor.charAt(i))) { + ++count; + } + } + return count; + + } + /** + * Generates all the required {@code UnwarrantedOptimismException} handlers for the current function. The employed + * strategy strives to maximize code reuse. Every handler constructs an array to hold the local variables, then + * fills in some trailing part of the local variables (those for which it has a unique suffix in the descriptor), + * then jumps to a handler for a prefix that's shared with other handlers. A handler that fills up locals up to + * position 0 will not jump to a prefix handler (as it has no prefix), but instead end with constructing and + * throwing a {@code RewriteException}. Since we lexicographically sort the entries, we only need to check every + * entry to its immediately preceding one for longest matching prefix. + * @return true if there is at least one exception handler + */ + private boolean generateUnwarrantedOptimismExceptionHandlers(final FunctionNode fn) { + if(!useOptimisticTypes()) { + return false; + } + + // Take the mapping of lvarSpecs -> labels, and turn them into a descending lexicographically sorted list of + // handler specifications. + final Map<String, Collection<Label>> unwarrantedOptimismHandlers = lc.popUnwarrantedOptimismHandlers(); + if(unwarrantedOptimismHandlers.isEmpty()) { + return false; + } + + method.lineNumber(0); + + final List<OptimismExceptionHandlerSpec> handlerSpecs = new ArrayList<>(unwarrantedOptimismHandlers.size() * 4/3); + for(final String spec: unwarrantedOptimismHandlers.keySet()) { + handlerSpecs.add(new OptimismExceptionHandlerSpec(spec, true)); + } + Collections.sort(handlerSpecs, Collections.reverseOrder()); + + // Map of local variable specifications to labels for populating the array for that local variable spec. + final Map<String, Label> delegationLabels = new HashMap<>(); + + // Do everything in a single pass over the handlerSpecs list. Note that the list can actually grow as we're + // passing through it as we might add new prefix handlers into it, so can't hoist size() outside of the loop. + for(int handlerIndex = 0; handlerIndex < handlerSpecs.size(); ++handlerIndex) { + final OptimismExceptionHandlerSpec spec = handlerSpecs.get(handlerIndex); + final String lvarSpec = spec.lvarSpec; + if(spec.catchTarget) { + assert !method.isReachable(); + // Start a catch block and assign the labels for this lvarSpec with it. + method._catch(unwarrantedOptimismHandlers.get(lvarSpec)); + // This spec is a catch target, so emit array creation code. The length of the array is the number of + // symbols - the number of uppercase characters. + method.load(countSymbolsInLvarTypeDescriptor(lvarSpec)); + method.newarray(Type.OBJECT_ARRAY); + } + if(spec.delegationTarget) { + // If another handler can delegate to this handler as its prefix, then put a jump target here for the + // shared code (after the array creation code, which is never shared). + method.label(delegationLabels.get(lvarSpec)); // label must exist + } + + final boolean lastHandler = handlerIndex == handlerSpecs.size() - 1; + + int lvarIndex; + final int firstArrayIndex; + final int firstLvarIndex; + Label delegationLabel; + final String commonLvarSpec; + if(lastHandler) { + // Last handler block, doesn't delegate to anything. + lvarIndex = 0; + firstLvarIndex = 0; + firstArrayIndex = 0; + delegationLabel = null; + commonLvarSpec = null; + } else { + // Not yet the last handler block, will definitely delegate to another handler; let's figure out which + // one. It can be an already declared handler further down the list, or it might need to declare a new + // prefix handler. + + // Since we're lexicographically ordered, the common prefix handler is defined by the common prefix of + // this handler and the next handler on the list. + final int nextHandlerIndex = handlerIndex + 1; + final String nextLvarSpec = handlerSpecs.get(nextHandlerIndex).lvarSpec; + commonLvarSpec = commonPrefix(lvarSpec, nextLvarSpec); + // We don't chop symbols in half + assert Character.isUpperCase(commonLvarSpec.charAt(commonLvarSpec.length() - 1)); + + // Let's find if we already have a declaration for such handler, or we need to insert it. + { + boolean addNewHandler = true; + int commonHandlerIndex = nextHandlerIndex; + for(; commonHandlerIndex < handlerSpecs.size(); ++commonHandlerIndex) { + final OptimismExceptionHandlerSpec forwardHandlerSpec = handlerSpecs.get(commonHandlerIndex); + final String forwardLvarSpec = forwardHandlerSpec.lvarSpec; + if(forwardLvarSpec.equals(commonLvarSpec)) { + // We already have a handler for the common prefix. + addNewHandler = false; + // Make sure we mark it as a delegation target. + forwardHandlerSpec.delegationTarget = true; + break; + } else if(!forwardLvarSpec.startsWith(commonLvarSpec)) { + break; + } + } + if(addNewHandler) { + // We need to insert a common prefix handler. Note handlers created with catchTarget == false + // will automatically have delegationTarget == true (because that's the only reason for their + // existence). + handlerSpecs.add(commonHandlerIndex, new OptimismExceptionHandlerSpec(commonLvarSpec, false)); + } + } + + firstArrayIndex = countSymbolsInLvarTypeDescriptor(commonLvarSpec); + lvarIndex = 0; + for(int j = 0; j < commonLvarSpec.length(); ++j) { + lvarIndex += CodeGeneratorLexicalContext.getTypeForSlotDescriptor(commonLvarSpec.charAt(j)).getSlots(); + } + firstLvarIndex = lvarIndex; + + // Create a delegation label if not already present + delegationLabel = delegationLabels.get(commonLvarSpec); + if(delegationLabel == null) { + // uo_pa == "unwarranted optimism, populate array" + delegationLabel = new Label("uo_pa_" + commonLvarSpec); + delegationLabels.put(commonLvarSpec, delegationLabel); + } + } + + // Load local variables handled by this handler on stack + int args = 0; + boolean symbolHadValue = false; + for(int typeIndex = commonLvarSpec == null ? 0 : commonLvarSpec.length(); typeIndex < lvarSpec.length(); ++typeIndex) { + final char typeDesc = lvarSpec.charAt(typeIndex); + final Type lvarType = CodeGeneratorLexicalContext.getTypeForSlotDescriptor(typeDesc); + if (!lvarType.isUnknown()) { + method.load(lvarType, lvarIndex); + symbolHadValue = true; + args++; + } else if(typeDesc == 'U' && !symbolHadValue) { + // Symbol boundary with undefined last value. Check if all previous values for this symbol were also + // undefined; if so, emit one explicit Undefined. This serves to ensure that we're emiting exactly + // one value for every symbol that uses local slots. While we could in theory ignore symbols that + // are undefined (in other words, dead) at the point where this exception was thrown, unfortunately + // we can't do it in practice. The reason for this is that currently our liveness analysis is + // coarse (it can determine whether a symbol has not been read with a particular type anywhere in + // the function being compiled, but that's it), and a symbol being promoted to Object due to a + // deoptimization will suddenly show up as "live for Object type", and previously dead U->O + // conversions on loop entries will suddenly become alive in the deoptimized method which will then + // expect a value for that slot in its continuation handler. If we had precise liveness analysis, we + // could go back to excluding known dead symbols from the payload of the RewriteException. + if(method.peekType() == Type.UNDEFINED) { + method.dup(); + } else { + method.loadUndefined(Type.OBJECT); + } + args++; + } + if(Character.isUpperCase(typeDesc)) { + // Reached symbol boundary; reset flag for the next symbol. + symbolHadValue = false; + } + lvarIndex += lvarType.getSlots(); + } + assert args > 0; + // Delegate actual storing into array to an array populator utility method. + //on the stack: + // object array to be populated + // start index + // a lot of types + method.dynamicArrayPopulatorCall(args + 1, firstArrayIndex); + if(delegationLabel != null) { + // We cascade to a prefix handler to fill out the rest of the local variables and throw the + // RewriteException. + assert !lastHandler; + assert commonLvarSpec != null; + // Must undefine the local variables that we have already processed for the sake of correct join on the + // delegate label + method.undefineLocalVariables(firstLvarIndex, true); + final OptimismExceptionHandlerSpec nextSpec = handlerSpecs.get(handlerIndex + 1); + // If the delegate immediately follows, and it's not a catch target (so it doesn't have array setup + // code) don't bother emitting a jump, as we'd just jump to the next instruction. + if(!nextSpec.lvarSpec.equals(commonLvarSpec) || nextSpec.catchTarget) { + method._goto(delegationLabel); + } + } else { + assert lastHandler; + // Nothing to delegate to, so this handler must create and throw the RewriteException. + // At this point we have the UnwarrantedOptimismException and the Object[] with local variables on + // stack. We need to create a RewriteException, push two references to it below the constructor + // arguments, invoke the constructor, and throw the exception. + loadConstant(getByteCodeSymbolNames(fn)); + if (isRestOf()) { + loadConstant(getContinuationEntryPoints()); + method.invoke(CREATE_REWRITE_EXCEPTION_REST_OF); + } else { + method.invoke(CREATE_REWRITE_EXCEPTION); + } + method.athrow(); + } + } + return true; + } + + private static String[] getByteCodeSymbolNames(final FunctionNode fn) { + // Only names of local variables on the function level are captured. This information is used to reduce + // deoptimizations, so as much as we can capture will help. We rely on the fact that function wide variables are + // all live all the time, so the array passed to rewrite exception contains one element for every slotted symbol + // here. + final List<String> names = new ArrayList<>(); + for (final Symbol symbol: fn.getBody().getSymbols()) { + if (symbol.hasSlot()) { + if (symbol.isScope()) { + // slot + scope can only be true for parameters + assert symbol.isParam(); + names.add(null); + } else { + names.add(symbol.getName()); + } + } + } + return names.toArray(new String[names.size()]); + } + + private static String commonPrefix(final String s1, final String s2) { + final int l1 = s1.length(); + final int l = Math.min(l1, s2.length()); + int lms = -1; // last matching symbol + for(int i = 0; i < l; ++i) { + final char c1 = s1.charAt(i); + if(c1 != s2.charAt(i)) { + return s1.substring(0, lms + 1); + } else if(Character.isUpperCase(c1)) { + lms = i; + } + } + return l == l1 ? s1 : s2; + } + + private static class OptimismExceptionHandlerSpec implements Comparable<OptimismExceptionHandlerSpec> { + private final String lvarSpec; + private final boolean catchTarget; + private boolean delegationTarget; + + OptimismExceptionHandlerSpec(final String lvarSpec, final boolean catchTarget) { + this.lvarSpec = lvarSpec; + this.catchTarget = catchTarget; + if(!catchTarget) { + delegationTarget = true; + } + } + + @Override + public int compareTo(final OptimismExceptionHandlerSpec o) { + return lvarSpec.compareTo(o.lvarSpec); + } + + @Override + public String toString() { + final StringBuilder b = new StringBuilder(64).append("[HandlerSpec ").append(lvarSpec); + if(catchTarget) { + b.append(", catchTarget"); + } + if(delegationTarget) { + b.append(", delegationTarget"); + } + return b.append("]").toString(); + } + } + + private static class ContinuationInfo { + private final Label handlerLabel; + private Label targetLabel; // Label for the target instruction. + int lvarCount; + // Indices of local variables that need to be loaded on the stack when this node completes + private int[] stackStoreSpec; + // Types of values loaded on the stack + private Type[] stackTypes; + // If non-null, this node should perform the requisite type conversion + private Type returnValueType; + // If we are in the middle of an object literal initialization, we need to update the map + private PropertyMap objectLiteralMap; + // Object literal stack depth for object literal - not necessarly top if property is a tree + private int objectLiteralStackDepth = -1; + // The line number at the continuation point + private int lineNumber; + // The active catch label, in case the continuation point is in a try/catch block + private Label catchLabel; + // The number of scopes that need to be popped before control is transferred to the catch label. + private int exceptionScopePops; + + ContinuationInfo() { + this.handlerLabel = new Label("continuation_handler"); + } + + Label getHandlerLabel() { + return handlerLabel; + } + + boolean hasTargetLabel() { + return targetLabel != null; + } + + Label getTargetLabel() { + return targetLabel; + } + + void setTargetLabel(final Label targetLabel) { + this.targetLabel = targetLabel; + } + + int[] getStackStoreSpec() { + return stackStoreSpec.clone(); + } + + void setStackStoreSpec(final int[] stackStoreSpec) { + this.stackStoreSpec = stackStoreSpec; + } + + Type[] getStackTypes() { + return stackTypes.clone(); + } + + void setStackTypes(final Type[] stackTypes) { + this.stackTypes = stackTypes; + } + + Type getReturnValueType() { + return returnValueType; + } + + void setReturnValueType(final Type returnValueType) { + this.returnValueType = returnValueType; + } + + int getObjectLiteralStackDepth() { + return objectLiteralStackDepth; + } + + void setObjectLiteralStackDepth(final int objectLiteralStackDepth) { + this.objectLiteralStackDepth = objectLiteralStackDepth; + } + + PropertyMap getObjectLiteralMap() { + return objectLiteralMap; + } + + void setObjectLiteralMap(final PropertyMap objectLiteralMap) { + this.objectLiteralMap = objectLiteralMap; + } + + @Override + public String toString() { + return "[localVariableTypes=" + targetLabel.getStack().getLocalVariableTypesCopy() + ", stackStoreSpec=" + + Arrays.toString(stackStoreSpec) + ", returnValueType=" + returnValueType + "]"; + } + } + + private ContinuationInfo getContinuationInfo() { + return fnIdToContinuationInfo.get(lc.getCurrentFunction().getId()); + } + + private void generateContinuationHandler() { + if (!isRestOf()) { + return; + } + + final ContinuationInfo ci = getContinuationInfo(); + method.label(ci.getHandlerLabel()); + + // There should never be an exception thrown from the continuation handler, but in case there is (meaning, + // Nashorn has a bug), then line number 0 will be an indication of where it came from (line numbers are Uint16). + method.lineNumber(0); + + final Label.Stack stack = ci.getTargetLabel().getStack(); + final List<Type> lvarTypes = stack.getLocalVariableTypesCopy(); + final BitSet symbolBoundary = stack.getSymbolBoundaryCopy(); + final int lvarCount = ci.lvarCount; + + final Type rewriteExceptionType = Type.typeFor(RewriteException.class); + // Store the RewriteException into an unused local variable slot. + method.load(rewriteExceptionType, 0); + method.storeTemp(rewriteExceptionType, lvarCount); + // Get local variable array + method.load(rewriteExceptionType, 0); + method.invoke(RewriteException.GET_BYTECODE_SLOTS); + // Store local variables. Note that deoptimization might introduce new value types for existing local variables, + // so we must use both liveLocals and symbolBoundary, as in some cases (when the continuation is inside of a try + // block) we need to store the incoming value into multiple slots. The optimism exception handlers will have + // exactly one array element for every symbol that uses bytecode storage. If in the originating method the value + // was undefined, there will be an explicit Undefined value in the array. + int arrayIndex = 0; + for(int lvarIndex = 0; lvarIndex < lvarCount;) { + final Type lvarType = lvarTypes.get(lvarIndex); + if(!lvarType.isUnknown()) { + method.dup(); + method.load(arrayIndex).arrayload(); + final Class<?> typeClass = lvarType.getTypeClass(); + // Deoptimization in array initializers can cause arrays to undergo component type widening + if(typeClass == long[].class) { + method.load(rewriteExceptionType, lvarCount); + method.invoke(RewriteException.TO_LONG_ARRAY); + } else if(typeClass == double[].class) { + method.load(rewriteExceptionType, lvarCount); + method.invoke(RewriteException.TO_DOUBLE_ARRAY); + } else if(typeClass == Object[].class) { + method.load(rewriteExceptionType, lvarCount); + method.invoke(RewriteException.TO_OBJECT_ARRAY); + } else { + if(!(typeClass.isPrimitive() || typeClass == Object.class)) { + // NOTE: this can only happen with dead stores. E.g. for the program "1; []; f();" in which the + // call to f() will deoptimize the call site, but it'll expect :return to have the type + // NativeArray. However, in the more optimal version, :return's only live type is int, therefore + // "{O}:return = []" is a dead store, and the variable will be sent into the continuation as + // Undefined, however NativeArray can't hold Undefined instance. + method.loadType(Type.getInternalName(typeClass)); + method.invoke(RewriteException.INSTANCE_OR_NULL); + } + method.convert(lvarType); + } + method.storeHidden(lvarType, lvarIndex, false); + } + final int nextLvarIndex = lvarIndex + lvarType.getSlots(); + if(symbolBoundary.get(nextLvarIndex - 1)) { + ++arrayIndex; + } + lvarIndex = nextLvarIndex; + } + if (AssertsEnabled.assertsEnabled()) { + method.load(arrayIndex); + method.invoke(RewriteException.ASSERT_ARRAY_LENGTH); + } else { + method.pop(); + } + + final int[] stackStoreSpec = ci.getStackStoreSpec(); + final Type[] stackTypes = ci.getStackTypes(); + final boolean isStackEmpty = stackStoreSpec.length == 0; + boolean replacedObjectLiteralMap = false; + if(!isStackEmpty) { + // Load arguments on the stack + final int objectLiteralStackDepth = ci.getObjectLiteralStackDepth(); + for(int i = 0; i < stackStoreSpec.length; ++i) { + final int slot = stackStoreSpec[i]; + method.load(lvarTypes.get(slot), slot); + method.convert(stackTypes[i]); + // stack: s0=object literal being initialized + // change map of s0 so that the property we are initilizing when we failed + // is now ci.returnValueType + if (i == objectLiteralStackDepth) { + method.dup(); + assert ci.getObjectLiteralMap() != null; + assert ScriptObject.class.isAssignableFrom(method.peekType().getTypeClass()) : method.peekType().getTypeClass() + " is not a script object"; + loadConstant(ci.getObjectLiteralMap()); + method.invoke(ScriptObject.SET_MAP); + replacedObjectLiteralMap = true; + } + } + } + // Must have emitted the code for replacing the map of an object literal if we have a set object literal stack depth + assert ci.getObjectLiteralStackDepth() == -1 || replacedObjectLiteralMap; + // Load RewriteException back. + method.load(rewriteExceptionType, lvarCount); + // Get rid of the stored reference + method.loadNull(); + method.storeHidden(Type.OBJECT, lvarCount); + // Mark it dead + method.markDeadSlots(lvarCount, Type.OBJECT.getSlots()); + + // Load return value on the stack + method.invoke(RewriteException.GET_RETURN_VALUE); + + final Type returnValueType = ci.getReturnValueType(); + + // Set up an exception handler for primitive type conversion of return value if needed + boolean needsCatch = false; + final Label targetCatchLabel = ci.catchLabel; + Label _try = null; + if(returnValueType.isPrimitive()) { + // If the conversion throws an exception, we want to report the line number of the continuation point. + method.lineNumber(ci.lineNumber); + + if(targetCatchLabel != METHOD_BOUNDARY) { + _try = new Label(""); + method.label(_try); + needsCatch = true; + } + } + + // Convert return value + method.convert(returnValueType); + + final int scopePopCount = needsCatch ? ci.exceptionScopePops : 0; + + // Declare a try/catch for the conversion. If no scopes need to be popped until the target catch block, just + // jump into it. Otherwise, we'll need to create a scope-popping catch block below. + final Label catchLabel = scopePopCount > 0 ? new Label("") : targetCatchLabel; + if(needsCatch) { + final Label _end_try = new Label(""); + method.label(_end_try); + method._try(_try, _end_try, catchLabel); + } + + // Jump to continuation point + method._goto(ci.getTargetLabel()); + + // Make a scope-popping exception delegate if needed + if(catchLabel != targetCatchLabel) { + method.lineNumber(0); + assert scopePopCount > 0; + method._catch(catchLabel); + popScopes(scopePopCount); + method.uncheckedGoto(targetCatchLabel); + } } } |