Reviewers: Vyacheslav Egorov,
Description:
Revert r9612, it hits an assertion under special circumstances.
Problematic code is e.g.:
function typeofViaVariable() {
var foo = typeof({})
return foo === "undefined";
}
Please review this at http://codereview.chromium.org/8283036/
SVN Base: http://v8.googlecode.com/svn/branches/bleeding_edge/
Affected files:
M src/hydrogen.h
M src/hydrogen.cc
Index: src/hydrogen.cc
===================================================================
--- src/hydrogen.cc (revision 9639)
+++ src/hydrogen.cc (working copy)
@@ -5789,68 +5789,38 @@
void HGraphBuilder::HandleLiteralCompareTypeof(CompareOperation* expr,
- HTypeof* typeof_expr,
+ Expression* sub_expr,
Handle<String> check) {
- HValue* value = typeof_expr->value();
+ CHECK_ALIVE(VisitForTypeOf(sub_expr));
+ HValue* value = Pop();
HTypeofIsAndBranch* instr = new(zone()) HTypeofIsAndBranch(value, check);
instr->set_position(expr->position());
- ast_context()->ReturnControl(instr, expr->id());
- typeof_expr->DeleteAndReplaceWith(NULL);
+ return ast_context()->ReturnControl(instr, expr->id());
}
-static bool MatchLiteralCompareNil(HValue* left,
- Token::Value op,
- HValue* right,
- Handle<Object> nil,
- HValue** expr) {
- if (left->IsConstant() &&
- HConstant::cast(left)->handle().is_identical_to(nil) &&
- Token::IsEqualityOp(op)) {
- *expr = right;
+bool HGraphBuilder::TryLiteralCompare(CompareOperation* expr) {
+ Expression *sub_expr;
+ Handle<String> check;
+ if (expr->IsLiteralCompareTypeof(&sub_expr, &check)) {
+ HandleLiteralCompareTypeof(expr, sub_expr, check);
return true;
}
- return false;
-}
+ if (expr->IsLiteralCompareUndefined(&sub_expr)) {
+ HandleLiteralCompareNil(expr, sub_expr, kUndefinedValue);
+ return true;
+ }
-static bool MatchLiteralCompareTypeof(HValue* left,
- Token::Value op,
- HValue* right,
- HTypeof** typeof_expr,
- Handle<String>* check) {
- if (left->IsTypeof() &&
- Token::IsEqualityOp(op) &&
- right->IsConstant() &&
- HConstant::cast(right)->HasStringValue()) {
- *typeof_expr = HTypeof::cast(left);
- *check = Handle<String>::cast(HConstant::cast(right)->handle());
+ if (expr->IsLiteralCompareNull(&sub_expr)) {
+ HandleLiteralCompareNil(expr, sub_expr, kNullValue);
return true;
}
+
return false;
}
-static bool IsLiteralCompareTypeof(HValue* left,
- Token::Value op,
- HValue* right,
- HTypeof** typeof_expr,
- Handle<String>* check) {
- return MatchLiteralCompareTypeof(left, op, right, typeof_expr, check) ||
- MatchLiteralCompareTypeof(right, op, left, typeof_expr, check);
-}
-
-
-static bool IsLiteralCompareNil(HValue* left,
- Token::Value op,
- HValue* right,
- Handle<Object> nil,
- HValue** expr) {
- return MatchLiteralCompareNil(left, op, right, nil, expr) ||
- MatchLiteralCompareNil(right, op, left, nil, expr);
-}
-
-
void HGraphBuilder::VisitCompareOperation(CompareOperation* expr) {
ASSERT(!HasStackOverflow());
ASSERT(current_block() != NULL);
@@ -5868,9 +5838,11 @@
return ast_context()->ReturnControl(instr, expr->id());
}
+ // Check for special cases that compare against literals.
+ if (TryLiteralCompare(expr)) return;
+
TypeInfo type_info = oracle()->CompareType(expr);
// Check if this expression was ever executed according to type feedback.
- // Note that for the special typeof/null/undefined cases we get unknown
here.
if (type_info.IsUninitialized()) {
AddInstruction(new(zone()) HSoftDeoptimize);
current_block()->MarkAsDeoptimizing();
@@ -5885,20 +5857,6 @@
HValue* left = Pop();
Token::Value op = expr->op();
- HTypeof* typeof_expr = NULL;
- Handle<String> check;
- if (IsLiteralCompareTypeof(left, op, right, &typeof_expr, &check)) {
- return HandleLiteralCompareTypeof(expr, typeof_expr, check);
- }
- HValue* sub_expr = NULL;
- Factory* f = graph()->isolate()->factory();
- if (IsLiteralCompareNil(left, op, right, f->undefined_value(),
&sub_expr)) {
- return HandleLiteralCompareNil(expr, sub_expr, kUndefinedValue);
- }
- if (IsLiteralCompareNil(left, op, right, f->null_value(), &sub_expr)) {
- return HandleLiteralCompareNil(expr, sub_expr, kNullValue);
- }
-
if (op == Token::INSTANCEOF) {
// Check to see if the rhs of the instanceof is a global function not
// residing in new space. If it is we assume that the function will
stay the
@@ -5987,11 +5945,13 @@
void HGraphBuilder::HandleLiteralCompareNil(CompareOperation* expr,
- HValue* value,
+ Expression* sub_expr,
NilValue nil) {
ASSERT(!HasStackOverflow());
ASSERT(current_block() != NULL);
ASSERT(current_block()->HasPredecessor());
+ CHECK_ALIVE(VisitForValue(sub_expr));
+ HValue* value = Pop();
EqualityKind kind =
expr->op() == Token::EQ_STRICT ? kStrictEquality :
kNonStrictEquality;
HIsNilAndBranch* instr = new(zone()) HIsNilAndBranch(value, kind, nil);
Index: src/hydrogen.h
===================================================================
--- src/hydrogen.h (revision 9639)
+++ src/hydrogen.h (working copy)
@@ -912,11 +912,12 @@
HValue* receiver,
SmallMapList* types,
Handle<String> name);
+ bool TryLiteralCompare(CompareOperation* expr);
void HandleLiteralCompareTypeof(CompareOperation* expr,
- HTypeof* typeof_expr,
+ Expression* sub_expr,
Handle<String> check);
void HandleLiteralCompareNil(CompareOperation* expr,
- HValue* value,
+ Expression* sub_expr,
NilValue nil);
HStringCharCodeAt* BuildStringCharCodeAt(HValue* context,
--
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