2015-03-10 Michael Collison <michael.collison@linaro.org>

	Backport from trunk r217852.
	2014-11-20  Tejas Belagod  <tejas.belagod@arm.com>

	* config/aarch64/aarch64-protos.h (aarch64_classify_symbol):
	Fixup prototype.
	* config/aarch64/aarch64.c (aarch64_expand_mov_immediate,
	aarch64_cannot_force_const_mem, aarch64_classify_address,
	aarch64_classify_symbolic_expression): Fixup call to
	aarch64_classify_symbol.
	(aarch64_classify_symbol): Add range-checking for
	symbol + offset addressing for tiny and small models.

2015-03-10  Michael Collison  <michael.collison@linaro.org>

	Backport from trunk r217852.
	2014-11-20  Tejas Belagod  <tejas.belagod@arm.com>

	* gcc.target/aarch64/symbol-range.c: New.
	* gcc.target/aarch64/symbol-range-tiny.c: New.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/linaro/gcc-4_9-branch@221300 138bc75d-0d04-0410-961f-82ee72b054a4

6 files changed, 69 insertions, 8 deletions

diff --git a/gcc/ChangeLog.linaro b/gcc/ChangeLog.linaro
index af134cf7bf3..c3008875183 100644
--- a/gcc/ChangeLog.linaro
+++ b/gcc/ChangeLog.linaro
@@ -1,3 +1,17 @@
+2015-03-10  Michael Collison  <michael.collison@linaro.org>
+
+	Backport from trunk r217852.
+	2014-11-20  Tejas Belagod  <tejas.belagod@arm.com>
+
+	* config/aarch64/aarch64-protos.h (aarch64_classify_symbol):
+	Fixup prototype.
+	* config/aarch64/aarch64.c (aarch64_expand_mov_immediate,
+	aarch64_cannot_force_const_mem, aarch64_classify_address,
+	aarch64_classify_symbolic_expression): Fixup call to
+	aarch64_classify_symbol.
+	(aarch64_classify_symbol): Add range-checking for
+	symbol + offset addressing for tiny and small models.
+
 2015-03-06  Christophe Lyon  <christophe.lyon@linaro.org>
 
 	Backport from trunk r217707.
diff --git a/gcc/config/aarch64/aarch64-protos.h b/gcc/config/aarch64/aarch64-protos.h
index 379df12031f..b0e5a31e3e7 100644
--- a/gcc/config/aarch64/aarch64-protos.h
+++ b/gcc/config/aarch64/aarch64-protos.h
@@ -216,7 +216,7 @@ bool aarch64_uimm12_shift (HOST_WIDE_INT);
 const char *aarch64_output_casesi (rtx *);
 const char *aarch64_rewrite_selected_cpu (const char *name);
 
-enum aarch64_symbol_type aarch64_classify_symbol (rtx,
+enum aarch64_symbol_type aarch64_classify_symbol (rtx, rtx,
 						  enum aarch64_symbol_context);
 enum aarch64_symbol_type aarch64_classify_tls_symbol (rtx);
 enum reg_class aarch64_regno_regclass (unsigned);
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index eb4554bdd83..4bbcca74eb9 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -1324,7 +1324,7 @@ aarch64_expand_mov_immediate (rtx dest, rtx imm)
 	 before we start classifying the symbol.  */
       split_const (imm, &base, &offset);
 
-      sty = aarch64_classify_symbol (base, SYMBOL_CONTEXT_ADR);
+      sty = aarch64_classify_symbol (base, offset, SYMBOL_CONTEXT_ADR);
       switch (sty)
 	{
 	case SYMBOL_FORCE_TO_MEM:
@@ -2994,7 +2994,7 @@ aarch64_cannot_force_const_mem (enum machine_mode mode ATTRIBUTE_UNUSED, rtx x)
   split_const (x, &base, &offset);
   if (GET_CODE (base) == SYMBOL_REF || GET_CODE (base) == LABEL_REF)
     {
-      if (aarch64_classify_symbol (base, SYMBOL_CONTEXT_ADR)
+      if (aarch64_classify_symbol (base, offset, SYMBOL_CONTEXT_ADR)
 	  != SYMBOL_FORCE_TO_MEM)
 	return true;
       else
@@ -3408,7 +3408,7 @@ aarch64_classify_address (struct aarch64_address_info *info,
 	  rtx sym, offs;
 	  split_const (info->offset, &sym, &offs);
 	  if (GET_CODE (sym) == SYMBOL_REF
-	      && (aarch64_classify_symbol (sym, SYMBOL_CONTEXT_MEM)
+	      && (aarch64_classify_symbol (sym, offs, SYMBOL_CONTEXT_MEM)
 		  == SYMBOL_SMALL_ABSOLUTE))
 	    {
 	      /* The symbol and offset must be aligned to the access size.  */
@@ -3465,7 +3465,7 @@ aarch64_classify_symbolic_expression (rtx x,
   rtx offset;
 
   split_const (x, &x, &offset);
-  return aarch64_classify_symbol (x, context);
+  return aarch64_classify_symbol (x, offset, context);
 }
 
 
@@ -6607,7 +6607,7 @@ aarch64_classify_tls_symbol (rtx x)
    LABEL_REF X in context CONTEXT.  */
 
 enum aarch64_symbol_type
-aarch64_classify_symbol (rtx x,
+aarch64_classify_symbol (rtx x, rtx offset,
 			 enum aarch64_symbol_context context ATTRIBUTE_UNUSED)
 {
   if (GET_CODE (x) == LABEL_REF)
@@ -6641,12 +6641,25 @@ aarch64_classify_symbol (rtx x,
       switch (aarch64_cmodel)
 	{
 	case AARCH64_CMODEL_TINY:
-	  if (SYMBOL_REF_WEAK (x))
+	  /* When we retreive symbol + offset address, we have to make sure
+	     the offset does not cause overflow of the final address.  But
+	     we have no way of knowing the address of symbol at compile time
+	     so we can't accurately say if the distance between the PC and
+	     symbol + offset is outside the addressible range of +/-1M in the
+	     TINY code model.  So we rely on images not being greater than
+	     1M and cap the offset at 1M and anything beyond 1M will have to
+	     be loaded using an alternative mechanism.  */
+	  if (SYMBOL_REF_WEAK (x)
+	      || INTVAL (offset) < -1048575 || INTVAL (offset) > 1048575)
 	    return SYMBOL_FORCE_TO_MEM;
 	  return SYMBOL_TINY_ABSOLUTE;
 
 	case AARCH64_CMODEL_SMALL:
-	  if (SYMBOL_REF_WEAK (x))
+	  /* Same reasoning as the tiny code model, but the offset cap here is
+	     4G.  */
+	  if (SYMBOL_REF_WEAK (x)
+	      || INTVAL (offset) < (HOST_WIDE_INT) -4294967263
+	      || INTVAL (offset) > (HOST_WIDE_INT) 4294967264)
 	    return SYMBOL_FORCE_TO_MEM;
 	  return SYMBOL_SMALL_ABSOLUTE;
 
diff --git a/gcc/testsuite/ChangeLog.linaro b/gcc/testsuite/ChangeLog.linaro
index 93775f9b058..2dc587a6608 100644
--- a/gcc/testsuite/ChangeLog.linaro
+++ b/gcc/testsuite/ChangeLog.linaro
@@ -1,3 +1,11 @@
+2015-03-10  Michael Collison  <michael.collison@linaro.org>
+
+	Backport from trunk r217852.
+	2014-11-20  Tejas Belagod  <tejas.belagod@arm.com>
+
+	* gcc.target/aarch64/symbol-range.c: New.
+	* gcc.target/aarch64/symbol-range-tiny.c: New.
+
 2015-03-06  Christophe Lyon  <christophe.lyon@linaro.org>
 
 	Backport from trunk r218463, r219764, r219765, r219767, r219914,
diff --git a/gcc/testsuite/gcc.target/aarch64/symbol-range-tiny.c b/gcc/testsuite/gcc.target/aarch64/symbol-range-tiny.c
new file mode 100644
index 00000000000..d7d2039694f
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/symbol-range-tiny.c
@@ -0,0 +1,13 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -save-temps -mcmodel=tiny" } */
+
+int fixed_regs[0x00200000];
+
+int
+foo()
+{
+  return fixed_regs[0x00080000];
+}
+
+/* { dg-final { scan-assembler-not "adr\tx\[0-9\]+, fixed_regs\\\+" } } */
+/* { dg-final {cleanup-saved-temps } } */
diff --git a/gcc/testsuite/gcc.target/aarch64/symbol-range.c b/gcc/testsuite/gcc.target/aarch64/symbol-range.c
new file mode 100644
index 00000000000..f999bb38102
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/symbol-range.c
@@ -0,0 +1,13 @@
+/* { dg-do compile } */
+/* { dg-options "-O3 -save-temps -mcmodel=small" } */
+
+int fixed_regs[0x200000000ULL];
+
+int
+foo()
+{
+  return fixed_regs[0x100000000ULL];
+}
+
+/* { dg-final { scan-assembler-not "adrp\tx\[0-9\]+, fixed_regs\\\+" } } */
+/* { dg-final {cleanup-saved-temps } } */