aboutsummaryrefslogtreecommitdiff
path: root/code/tools/lcc/src/dag.c
diff options
context:
space:
mode:
Diffstat (limited to 'code/tools/lcc/src/dag.c')
-rw-r--r--code/tools/lcc/src/dag.c736
1 files changed, 736 insertions, 0 deletions
diff --git a/code/tools/lcc/src/dag.c b/code/tools/lcc/src/dag.c
new file mode 100644
index 0000000..420cbe7
--- /dev/null
+++ b/code/tools/lcc/src/dag.c
@@ -0,0 +1,736 @@
+#include "c.h"
+
+
+#define iscall(op) (generic(op) == CALL \
+ || (IR->mulops_calls \
+ && (generic(op)==DIV||generic(op)==MOD||generic(op)==MUL) \
+ && ( optype(op)==U || optype(op)==I)))
+static Node forest;
+static struct dag {
+ struct node node;
+ struct dag *hlink;
+} *buckets[16];
+int nodecount;
+static Tree firstarg;
+int assignargs = 1;
+int prunetemps = -1;
+static Node *tail;
+
+static int depth = 0;
+static Node replace(Node);
+static Node prune(Node);
+static Node asgnnode(Symbol, Node);
+static struct dag *dagnode(int, Node, Node, Symbol);
+static Symbol equated(Symbol);
+static void fixup(Node);
+static void labelnode(int);
+static void list(Node);
+static void kill(Symbol);
+static Node node(int, Node, Node, Symbol);
+static void printdag1(Node, int, int);
+static void printnode(Node, int, int);
+static void reset(void);
+static Node tmpnode(Node);
+static void typestab(Symbol, void *);
+static Node undag(Node);
+static Node visit(Node, int);
+static void unlist(void);
+void walk(Tree tp, int tlab, int flab) {
+ listnodes(tp, tlab, flab);
+ if (forest) {
+ Node list = forest->link;
+ forest->link = NULL;
+ if (!IR->wants_dag)
+ list = undag(list);
+ code(Gen)->u.forest = list;
+ forest = NULL;
+ }
+ reset();
+ deallocate(STMT);
+}
+
+static Node node(int op, Node l, Node r, Symbol sym) {
+ int i;
+ struct dag *p;
+
+ i = (opindex(op)^((unsigned long)sym>>2))&(NELEMS(buckets)-1);
+ for (p = buckets[i]; p; p = p->hlink)
+ if (p->node.op == op && p->node.syms[0] == sym
+ && p->node.kids[0] == l && p->node.kids[1] == r)
+ return &p->node;
+ p = dagnode(op, l, r, sym);
+ p->hlink = buckets[i];
+ buckets[i] = p;
+ ++nodecount;
+ return &p->node;
+}
+static struct dag *dagnode(int op, Node l, Node r, Symbol sym) {
+ struct dag *p;
+
+ NEW0(p, FUNC);
+ p->node.op = op;
+ if ((p->node.kids[0] = l) != NULL)
+ ++l->count;
+ if ((p->node.kids[1] = r) != NULL)
+ ++r->count;
+ p->node.syms[0] = sym;
+ return p;
+}
+Node newnode(int op, Node l, Node r, Symbol sym) {
+ return &dagnode(op, l, r, sym)->node;
+}
+static void kill(Symbol p) {
+ int i;
+ struct dag **q;
+
+ for (i = 0; i < NELEMS(buckets); i++)
+ for (q = &buckets[i]; *q; )
+ if (generic((*q)->node.op) == INDIR &&
+ (!isaddrop((*q)->node.kids[0]->op)
+ || (*q)->node.kids[0]->syms[0] == p)) {
+ *q = (*q)->hlink;
+ --nodecount;
+ } else
+ q = &(*q)->hlink;
+}
+static void reset(void) {
+ if (nodecount > 0)
+ memset(buckets, 0, sizeof buckets);
+ nodecount = 0;
+}
+Node listnodes(Tree tp, int tlab, int flab) {
+ Node p = NULL, l, r;
+ int op;
+
+ assert(tlab || flab || (tlab == 0 && flab == 0));
+ if (tp == NULL)
+ return NULL;
+ if (tp->node)
+ return tp->node;
+ op = tp->op + sizeop(tp->type->size);
+ switch (generic(tp->op)) {
+ case AND: { if (depth++ == 0) reset();
+ if (flab) {
+ listnodes(tp->kids[0], 0, flab);
+ listnodes(tp->kids[1], 0, flab);
+ } else {
+ listnodes(tp->kids[0], 0, flab = genlabel(1));
+ listnodes(tp->kids[1], tlab, 0);
+ labelnode(flab);
+ }
+ depth--; } break;
+ case OR: { if (depth++ == 0)
+ reset();
+ if (tlab) {
+ listnodes(tp->kids[0], tlab, 0);
+ listnodes(tp->kids[1], tlab, 0);
+ } else {
+ tlab = genlabel(1);
+ listnodes(tp->kids[0], tlab, 0);
+ listnodes(tp->kids[1], 0, flab);
+ labelnode(tlab);
+ }
+ depth--;
+ } break;
+ case NOT: { return listnodes(tp->kids[0], flab, tlab); }
+ case COND: { Tree q = tp->kids[1];
+ assert(tlab == 0 && flab == 0);
+ if (tp->u.sym)
+ addlocal(tp->u.sym);
+ flab = genlabel(2);
+ listnodes(tp->kids[0], 0, flab);
+ assert(q && q->op == RIGHT);
+ reset();
+ listnodes(q->kids[0], 0, 0);
+ if (forest->op == LABEL+V) {
+ equatelab(forest->syms[0], findlabel(flab + 1));
+ unlist();
+ }
+ list(jump(flab + 1));
+ labelnode(flab);
+ listnodes(q->kids[1], 0, 0);
+ if (forest->op == LABEL+V) {
+ equatelab(forest->syms[0], findlabel(flab + 1));
+ unlist();
+ }
+ labelnode(flab + 1);
+
+ if (tp->u.sym)
+ p = listnodes(idtree(tp->u.sym), 0, 0); } break;
+ case CNST: { Type ty = unqual(tp->type);
+ assert(ty->u.sym);
+ if (tlab || flab) {
+ assert(ty == inttype);
+ if (tlab && tp->u.v.i != 0)
+ list(jump(tlab));
+ else if (flab && tp->u.v.i == 0)
+ list(jump(flab));
+ }
+ else if (ty->u.sym->addressed)
+ p = listnodes(cvtconst(tp), 0, 0);
+ else
+ p = node(op, NULL, NULL, constant(ty, tp->u.v)); } break;
+ case RIGHT: { if ( tp->kids[0] && tp->kids[1]
+ && generic(tp->kids[1]->op) == ASGN
+ && ((generic(tp->kids[0]->op) == INDIR
+ && tp->kids[0]->kids[0] == tp->kids[1]->kids[0])
+ || (tp->kids[0]->op == FIELD
+ && tp->kids[0] == tp->kids[1]->kids[0]))) {
+ assert(tlab == 0 && flab == 0);
+ if (generic(tp->kids[0]->op) == INDIR) {
+ p = listnodes(tp->kids[0], 0, 0);
+ list(p);
+ listnodes(tp->kids[1], 0, 0);
+ }
+ else {
+ assert(generic(tp->kids[0]->kids[0]->op) == INDIR);
+ list(listnodes(tp->kids[0]->kids[0], 0, 0));
+ p = listnodes(tp->kids[0], 0, 0);
+ listnodes(tp->kids[1], 0, 0);
+ }
+ } else if (tp->kids[1]) {
+ listnodes(tp->kids[0], 0, 0);
+ p = listnodes(tp->kids[1], tlab, flab);
+ } else
+ p = listnodes(tp->kids[0], tlab, flab); } break;
+ case JUMP: { assert(tlab == 0 && flab == 0);
+ assert(tp->u.sym == 0);
+ assert(tp->kids[0]);
+ l = listnodes(tp->kids[0], 0, 0);
+ list(newnode(JUMP+V, l, NULL, NULL));
+ reset(); } break;
+ case CALL: { Tree save = firstarg;
+ firstarg = NULL;
+ assert(tlab == 0 && flab == 0);
+ if (tp->op == CALL+B && !IR->wants_callb) {
+ Tree arg0 = tree(ARG+P, tp->kids[1]->type,
+ tp->kids[1], NULL);
+ if (IR->left_to_right)
+ firstarg = arg0;
+ l = listnodes(tp->kids[0], 0, 0);
+ if (!IR->left_to_right || firstarg) {
+ firstarg = NULL;
+ listnodes(arg0, 0, 0);
+ }
+ p = newnode(CALL+V, l, NULL, NULL);
+ } else {
+ l = listnodes(tp->kids[0], 0, 0);
+ r = listnodes(tp->kids[1], 0, 0);
+ p = newnode(tp->op == CALL+B ? tp->op : op, l, r, NULL);
+ }
+ NEW0(p->syms[0], FUNC);
+ assert(isptr(tp->kids[0]->type));
+ assert(isfunc(tp->kids[0]->type->type));
+ p->syms[0]->type = tp->kids[0]->type->type;
+ list(p);
+ reset();
+ cfunc->u.f.ncalls++;
+ firstarg = save;
+ } break;
+ case ARG: { assert(tlab == 0 && flab == 0);
+ if (IR->left_to_right)
+ listnodes(tp->kids[1], 0, 0);
+ if (firstarg) {
+ Tree arg = firstarg;
+ firstarg = NULL;
+ listnodes(arg, 0, 0);
+ }
+ l = listnodes(tp->kids[0], 0, 0);
+ list(newnode(tp->op == ARG+B ? tp->op : op, l, NULL, NULL));
+ forest->syms[0] = intconst(tp->type->size);
+ forest->syms[1] = intconst(tp->type->align);
+ if (!IR->left_to_right)
+ listnodes(tp->kids[1], 0, 0); } break;
+ case EQ: case NE: case GT: case GE: case LE:
+ case LT: { assert(tp->u.sym == 0);
+ assert(errcnt || tlab || flab);
+ l = listnodes(tp->kids[0], 0, 0);
+ r = listnodes(tp->kids[1], 0, 0);
+ assert(errcnt || opkind(l->op) == opkind(r->op));
+ assert(errcnt || optype(op) == optype(l->op));
+ if (tlab)
+ assert(flab == 0),
+ list(newnode(generic(tp->op) + opkind(l->op), l, r, findlabel(tlab)));
+ else if (flab) {
+ switch (generic(tp->op)) {
+ case EQ: op = NE; break;
+ case NE: op = EQ; break;
+ case GT: op = LE; break;
+ case LT: op = GE; break;
+ case GE: op = LT; break;
+ case LE: op = GT; break;
+ default: assert(0);
+ }
+ list(newnode(op + opkind(l->op), l, r, findlabel(flab)));
+ }
+ if (forest && forest->syms[0])
+ forest->syms[0]->ref++; } break;
+ case ASGN: { assert(tlab == 0 && flab == 0);
+ if (tp->kids[0]->op == FIELD) {
+ Tree x = tp->kids[0]->kids[0];
+ Field f = tp->kids[0]->u.field;
+ assert(generic(x->op) == INDIR);
+ reset();
+ l = listnodes(lvalue(x), 0, 0);
+ if (fieldsize(f) < 8*f->type->size) {
+ unsigned int fmask = fieldmask(f);
+ unsigned int mask = fmask<<fieldright(f);
+ Tree q = tp->kids[1];
+ if ((q->op == CNST+I && q->u.v.i == 0)
+ || (q->op == CNST+U && q->u.v.u == 0))
+ q = bittree(BAND, x, cnsttree(unsignedtype, (unsigned long)~mask));
+ else if ((q->op == CNST+I && (q->u.v.i&fmask) == fmask)
+ || (q->op == CNST+U && (q->u.v.u&fmask) == fmask))
+ q = bittree(BOR, x, cnsttree(unsignedtype, (unsigned long)mask));
+ else {
+ listnodes(q, 0, 0);
+ q = bittree(BOR,
+ bittree(BAND, rvalue(lvalue(x)),
+ cnsttree(unsignedtype, (unsigned long)~mask)),
+ bittree(BAND, shtree(LSH, cast(q, unsignedtype),
+ cnsttree(unsignedtype, (unsigned long)fieldright(f))),
+ cnsttree(unsignedtype, (unsigned long)mask)));
+ }
+ r = listnodes(q, 0, 0);
+ op = ASGN + ttob(q->type);
+ } else {
+ r = listnodes(tp->kids[1], 0, 0);
+ op = ASGN + ttob(tp->kids[1]->type);
+ }
+ } else {
+ l = listnodes(tp->kids[0], 0, 0);
+ r = listnodes(tp->kids[1], 0, 0);
+ }
+ list(newnode(tp->op == ASGN+B ? tp->op : op, l, r, NULL));
+ forest->syms[0] = intconst(tp->kids[1]->type->size);
+ forest->syms[1] = intconst(tp->kids[1]->type->align);
+ if (isaddrop(tp->kids[0]->op)
+ && !tp->kids[0]->u.sym->computed)
+ kill(tp->kids[0]->u.sym);
+ else
+ reset();
+ p = listnodes(tp->kids[1], 0, 0); } break;
+ case BOR: case BAND: case BXOR:
+ case ADD: case SUB: case RSH:
+ case LSH: { assert(tlab == 0 && flab == 0);
+ l = listnodes(tp->kids[0], 0, 0);
+ r = listnodes(tp->kids[1], 0, 0);
+ p = node(op, l, r, NULL); } break;
+ case DIV: case MUL:
+ case MOD: { assert(tlab == 0 && flab == 0);
+ l = listnodes(tp->kids[0], 0, 0);
+ r = listnodes(tp->kids[1], 0, 0);
+ p = node(op, l, r, NULL);
+ if (IR->mulops_calls && isint(tp->type)) {
+ list(p);
+ cfunc->u.f.ncalls++;
+ } } break;
+ case RET: { assert(tlab == 0 && flab == 0);
+ l = listnodes(tp->kids[0], 0, 0);
+ list(newnode(op, l, NULL, NULL)); } break;
+ case CVF: case CVI: case CVP:
+ case CVU: { assert(tlab == 0 && flab == 0);
+ assert(optype(tp->kids[0]->op) != optype(tp->op) || tp->kids[0]->type->size != tp->type->size);
+ l = listnodes(tp->kids[0], 0, 0);
+ p = node(op, l, NULL, intconst(tp->kids[0]->type->size));
+ } break;
+ case BCOM:
+ case NEG: { assert(tlab == 0 && flab == 0);
+ l = listnodes(tp->kids[0], 0, 0);
+ p = node(op, l, NULL, NULL); } break;
+ case INDIR: { Type ty = tp->kids[0]->type;
+ assert(tlab == 0 && flab == 0);
+ l = listnodes(tp->kids[0], 0, 0);
+ if (isptr(ty))
+ ty = unqual(ty)->type;
+ if (isvolatile(ty)
+ || (isstruct(ty) && unqual(ty)->u.sym->u.s.vfields))
+ p = newnode(tp->op == INDIR+B ? tp->op : op, l, NULL, NULL);
+ else
+ p = node(tp->op == INDIR+B ? tp->op : op, l, NULL, NULL); } break;
+ case FIELD: { Tree q = tp->kids[0];
+ if (tp->type == inttype) {
+ long n = fieldleft(tp->u.field);
+ q = shtree(RSH,
+ shtree(LSH, q, cnsttree(inttype, n)),
+ cnsttree(inttype, n + fieldright(tp->u.field)));
+ } else if (fieldsize(tp->u.field) < 8*tp->u.field->type->size)
+ q = bittree(BAND,
+ shtree(RSH, q, cnsttree(inttype, (long)fieldright(tp->u.field))),
+ cnsttree(unsignedtype, (unsigned long)fieldmask(tp->u.field)));
+ assert(tlab == 0 && flab == 0);
+ p = listnodes(q, 0, 0); } break;
+ case ADDRG:
+ case ADDRF: { assert(tlab == 0 && flab == 0);
+ p = node(tp->op + sizeop(voidptype->size), NULL, NULL, tp->u.sym);
+ } break;
+ case ADDRL: { assert(tlab == 0 && flab == 0);
+ if (tp->u.sym->temporary)
+ addlocal(tp->u.sym);
+ p = node(tp->op + sizeop(voidptype->size), NULL, NULL, tp->u.sym); } break;
+ default:assert(0);
+ }
+ tp->node = p;
+ return p;
+}
+static void list(Node p) {
+ if (p && p->link == NULL) {
+ if (forest) {
+ p->link = forest->link;
+ forest->link = p;
+ } else
+ p->link = p;
+ forest = p;
+ }
+}
+static void labelnode(int lab) {
+ assert(lab);
+ if (forest && forest->op == LABEL+V)
+ equatelab(findlabel(lab), forest->syms[0]);
+ else
+ list(newnode(LABEL+V, NULL, NULL, findlabel(lab)));
+ reset();
+}
+static void unlist(void) {
+ Node p;
+
+ assert(forest);
+ assert(forest != forest->link);
+ p = forest->link;
+ while (p->link != forest)
+ p = p->link;
+ p->link = forest->link;
+ forest = p;
+}
+Tree cvtconst(Tree p) {
+ Symbol q = constant(p->type, p->u.v);
+ Tree e;
+
+ if (q->u.c.loc == NULL)
+ q->u.c.loc = genident(STATIC, p->type, GLOBAL);
+ if (isarray(p->type)) {
+ e = simplify(ADDRG, atop(p->type), NULL, NULL);
+ e->u.sym = q->u.c.loc;
+ } else
+ e = idtree(q->u.c.loc);
+ return e;
+}
+void gencode(Symbol caller[], Symbol callee[]) {
+ Code cp;
+ Coordinate save;
+
+ if (prunetemps == -1)
+ prunetemps = !IR->wants_dag;
+ save = src;
+ if (assignargs) {
+ int i;
+ Symbol p, q;
+ cp = codehead.next->next;
+ codelist = codehead.next;
+ for (i = 0; (p = callee[i]) != NULL
+ && (q = caller[i]) != NULL; i++)
+ if (p->sclass != q->sclass || p->type != q->type)
+ walk(asgn(p, idtree(q)), 0, 0);
+ codelist->next = cp;
+ cp->prev = codelist;
+ }
+ if (glevel && IR->stabsym) {
+ int i;
+ Symbol p, q;
+ for (i = 0; (p = callee[i]) != NULL
+ && (q = caller[i]) != NULL; i++) {
+ (*IR->stabsym)(p);
+ if (p->sclass != q->sclass || p->type != q->type)
+ (*IR->stabsym)(q);
+ }
+ swtoseg(CODE);
+ }
+ cp = codehead.next;
+ for ( ; errcnt <= 0 && cp; cp = cp->next)
+ switch (cp->kind) {
+ case Address: (*IR->address)(cp->u.addr.sym, cp->u.addr.base,
+ cp->u.addr.offset); break;
+ case Blockbeg: {
+ Symbol *p = cp->u.block.locals;
+ (*IR->blockbeg)(&cp->u.block.x);
+ for ( ; *p; p++)
+ if ((*p)->ref != 0.0)
+ (*IR->local)(*p);
+ else if (glevel) (*IR->local)(*p);
+ }
+ break;
+ case Blockend: (*IR->blockend)(&cp->u.begin->u.block.x); break;
+ case Defpoint: src = cp->u.point.src; break;
+ case Gen: case Jump:
+ case Label: if (prunetemps)
+ cp->u.forest = prune(cp->u.forest);
+ fixup(cp->u.forest);
+ cp->u.forest = (*IR->gen)(cp->u.forest); break;
+ case Local: (*IR->local)(cp->u.var); break;
+ case Switch: break;
+ default: assert(0);
+ }
+ src = save;
+}
+static void fixup(Node p) {
+ for ( ; p; p = p->link)
+ switch (generic(p->op)) {
+ case JUMP:
+ if (specific(p->kids[0]->op) == ADDRG+P)
+ p->kids[0]->syms[0] =
+ equated(p->kids[0]->syms[0]);
+ break;
+ case LABEL: assert(p->syms[0] == equated(p->syms[0])); break;
+ case EQ: case GE: case GT: case LE: case LT: case NE:
+ assert(p->syms[0]);
+ p->syms[0] = equated(p->syms[0]);
+ }
+}
+static Symbol equated(Symbol p) {
+ { Symbol q; for (q = p->u.l.equatedto; q; q = q->u.l.equatedto) assert(p != q); }
+ while (p->u.l.equatedto)
+ p = p->u.l.equatedto;
+ return p;
+}
+void emitcode(void) {
+ Code cp;
+ Coordinate save;
+
+ save = src;
+ cp = codehead.next;
+ for ( ; errcnt <= 0 && cp; cp = cp->next)
+ switch (cp->kind) {
+ case Address: break;
+ case Blockbeg: if (glevel && IR->stabblock) {
+ (*IR->stabblock)('{', cp->u.block.level - LOCAL, cp->u.block.locals);
+ swtoseg(CODE);
+ }
+ break;
+ case Blockend: if (glevel && IR->stabblock) {
+ Code bp = cp->u.begin;
+ foreach(bp->u.block.identifiers, bp->u.block.level, typestab, NULL);
+ foreach(bp->u.block.types, bp->u.block.level, typestab, NULL);
+ (*IR->stabblock)('}', bp->u.block.level - LOCAL, bp->u.block.locals);
+ swtoseg(CODE);
+ }
+ break;
+ case Defpoint: src = cp->u.point.src;
+ if (glevel > 0 && IR->stabline) {
+ (*IR->stabline)(&cp->u.point.src); swtoseg(CODE); } break;
+ case Gen: case Jump:
+ case Label: if (cp->u.forest)
+ (*IR->emit)(cp->u.forest); break;
+ case Local: if (glevel && IR->stabsym) {
+ (*IR->stabsym)(cp->u.var);
+ swtoseg(CODE);
+ } break;
+ case Switch: { int i;
+ defglobal(cp->u.swtch.table, LIT);
+ (*IR->defaddress)(equated(cp->u.swtch.labels[0]));
+ for (i = 1; i < cp->u.swtch.size; i++) {
+ long k = cp->u.swtch.values[i-1];
+ while (++k < cp->u.swtch.values[i])
+ assert(k < LONG_MAX),
+ (*IR->defaddress)(equated(cp->u.swtch.deflab));
+ (*IR->defaddress)(equated(cp->u.swtch.labels[i]));
+ }
+ swtoseg(CODE);
+ } break;
+ default: assert(0);
+ }
+ src = save;
+}
+
+static Node undag(Node forest) {
+ Node p;
+
+ tail = &forest;
+ for (p = forest; p; p = p->link)
+ if (generic(p->op) == INDIR) {
+ assert(p->count >= 1);
+ visit(p, 1);
+ if (p->syms[2]) {
+ assert(p->syms[2]->u.t.cse);
+ p->syms[2]->u.t.cse = NULL;
+ addlocal(p->syms[2]);
+ }
+ } else if (iscall(p->op) && p->count >= 1)
+ visit(p, 1);
+ else {
+ assert(p->count == 0),
+ visit(p, 1);
+ *tail = p;
+ tail = &p->link;
+ }
+ *tail = NULL;
+ return forest;
+}
+static Node replace(Node p) {
+ if (p && ( generic(p->op) == INDIR
+ && generic(p->kids[0]->op) == ADDRL
+ && p->kids[0]->syms[0]->temporary
+ && p->kids[0]->syms[0]->u.t.replace)) {
+ p = p->kids[0]->syms[0]->u.t.cse;
+ if (generic(p->op) == INDIR && isaddrop(p->kids[0]->op))
+ p = newnode(p->op, newnode(p->kids[0]->op, NULL, NULL,
+ p->kids[0]->syms[0]), NULL, NULL);
+ else if (generic(p->op) == ADDRG)
+ p = newnode(p->op, NULL, NULL, p->syms[0]);
+ else
+ assert(0);
+ p->count = 1;
+ } else if (p) {
+ p->kids[0] = replace(p->kids[0]);
+ p->kids[1] = replace(p->kids[1]);
+ }
+ return p;
+}
+static Node prune(Node forest) {
+ Node p, *tail = &forest;
+ int count = 0;
+
+ for (p = forest; p; p = p->link) {
+ if (count > 0) {
+ p->kids[0] = replace(p->kids[0]);
+ p->kids[1] = replace(p->kids[1]);
+ }
+ if (( generic(p->op) == ASGN
+ && generic(p->kids[0]->op) == ADDRL
+ && p->kids[0]->syms[0]->temporary
+ && p->kids[0]->syms[0]->u.t.cse == p->kids[1])) {
+ Symbol tmp = p->kids[0]->syms[0];
+ if (!tmp->defined)
+ (*IR->local)(tmp);
+ tmp->defined = 1;
+ if (( generic(p->kids[1]->op) == INDIR
+ && isaddrop(p->kids[1]->kids[0]->op)
+ && p->kids[1]->kids[0]->syms[0]->sclass == REGISTER)
+ || (( generic(p->kids[1]->op) == INDIR
+ && isaddrop(p->kids[1]->kids[0]->op)) && tmp->sclass == AUTO)
+ || (generic(p->kids[1]->op) == ADDRG && tmp->sclass == AUTO)) {
+ tmp->u.t.replace = 1;
+ count++;
+ continue; /* and omit the assignment */
+ }
+ }
+ /* keep the assignment and other roots */
+ *tail = p;
+ tail = &(*tail)->link;
+ }
+ assert(*tail == NULL);
+ return forest;
+}
+static Node visit(Node p, int listed) {
+ if (p) {
+ if (p->syms[2])
+ p = tmpnode(p);
+ else if ((p->count <= 1 && !iscall(p->op))
+ || (p->count == 0 && iscall(p->op))) {
+ p->kids[0] = visit(p->kids[0], 0);
+ p->kids[1] = visit(p->kids[1], 0);
+ }
+
+ else if (specific(p->op) == ADDRL+P || specific(p->op) == ADDRF+P) {
+ assert(!listed);
+ p = newnode(p->op, NULL, NULL, p->syms[0]);
+ p->count = 1;
+ }
+ else if (p->op == INDIR+B) {
+ p = newnode(p->op, p->kids[0], NULL, NULL);
+ p->count = 1;
+ p->kids[0] = visit(p->kids[0], 0);
+ p->kids[1] = visit(p->kids[1], 0);
+ }
+ else {
+ p->kids[0] = visit(p->kids[0], 0);
+ p->kids[1] = visit(p->kids[1], 0);
+ p->syms[2] = temporary(REGISTER, btot(p->op, opsize(p->op)));
+ assert(!p->syms[2]->defined);
+ p->syms[2]->ref = 1;
+ p->syms[2]->u.t.cse = p;
+
+ *tail = asgnnode(p->syms[2], p);
+ tail = &(*tail)->link;
+ if (!listed)
+ p = tmpnode(p);
+ };
+ }
+ return p;
+}
+static Node tmpnode(Node p) {
+ Symbol tmp = p->syms[2];
+
+ assert(tmp);
+ if (--p->count == 0)
+ p->syms[2] = NULL;
+ p = newnode(INDIR + ttob(tmp->type),
+ newnode(ADDRL + ttob(voidptype), NULL, NULL, tmp), NULL, NULL);
+ p->count = 1;
+ return p;
+}
+static Node asgnnode(Symbol tmp, Node p) {
+ p = newnode(ASGN + ttob(tmp->type),
+ newnode(ADDRL + ttob(voidptype), NULL, NULL, tmp), p, NULL);
+ p->syms[0] = intconst(tmp->type->size);
+ p->syms[1] = intconst(tmp->type->align);
+ return p;
+}
+/* printdag - print dag p on fd, or the node list if p == 0 */
+void printdag(Node p, int fd) {
+ FILE *f = fd == 1 ? stdout : stderr;
+
+ printed(0);
+ if (p == 0) {
+ if ((p = forest) != NULL)
+ do {
+ p = p->link;
+ printdag1(p, fd, 0);
+ } while (p != forest);
+ } else if (*printed(nodeid((Tree)p)))
+ fprint(f, "node'%d printed above\n", nodeid((Tree)p));
+ else
+ printdag1(p, fd, 0);
+}
+
+/* printdag1 - recursively print dag p */
+static void printdag1(Node p, int fd, int lev) {
+ int id, i;
+
+ if (p == 0 || *printed(id = nodeid((Tree)p)))
+ return;
+ *printed(id) = 1;
+ for (i = 0; i < NELEMS(p->kids); i++)
+ printdag1(p->kids[i], fd, lev + 1);
+ printnode(p, fd, lev);
+}
+
+/* printnode - print fields of dag p */
+static void printnode(Node p, int fd, int lev) {
+ if (p) {
+ FILE *f = fd == 1 ? stdout : stderr;
+ int i, id = nodeid((Tree)p);
+ fprint(f, "%c%d%s", lev == 0 ? '\'' : '#', id,
+ &" "[id < 10 ? 0 : id < 100 ? 1 : 2]);
+ fprint(f, "%s count=%d", opname(p->op), p->count);
+ for (i = 0; i < NELEMS(p->kids) && p->kids[i]; i++)
+ fprint(f, " #%d", nodeid((Tree)p->kids[i]));
+ if (generic(p->op) == CALL && p->syms[0] && p->syms[0]->type)
+ fprint(f, " {%t}", p->syms[0]->type);
+ else
+ for (i = 0; i < NELEMS(p->syms) && p->syms[i]; i++)
+ if (p->syms[i]->name)
+ fprint(f, " %s", p->syms[i]->name);
+ else
+ fprint(f, " %p", p->syms[i]);
+ fprint(f, "\n");
+ }
+}
+
+/* typestab - emit stab entries for p */
+static void typestab(Symbol p, void *cl) {
+ if (!isfunc(p->type) && (p->sclass == EXTERN || p->sclass == STATIC) && IR->stabsym)
+ (*IR->stabsym)(p);
+ else if ((p->sclass == TYPEDEF || p->sclass == 0) && IR->stabtype)
+ (*IR->stabtype)(p);
+}
+