Reviewers: Kasper Lund,
Description:
Fix a bug in our handling of conditional expressions in test contexts.
In the FullCodeGenerator, we compile the true subexpression of a
conditional (ternary) expression in the inherited context of the
entire expression. This is correct for effect and value contexts, but
not for test contexts where the context includes a possible
fall-through label.
Please review this at http://codereview.chromium.org/3621013/show
Affected files:
M src/full-codegen.h
M src/full-codegen.cc
Index: src/full-codegen.cc
diff --git a/src/full-codegen.cc b/src/full-codegen.cc
index
796b0717cf0e84dc1a627cfeed126f4565e2ab2a..97987c27a80c7aae2c1349a12141fbcf171bad70
100644
--- a/src/full-codegen.cc
+++ b/src/full-codegen.cc
@@ -1128,9 +1128,14 @@ void
FullCodeGenerator::VisitConditional(Conditional* expr) {
__ bind(&true_case);
SetExpressionPosition(expr->then_expression(),
expr->then_expression_position());
- Visit(expr->then_expression());
- // If control flow falls through Visit, jump to done.
- if (!context()->IsTest()) {
+ if (context()->IsTest()) {
+ const TestContext* for_test = TestContext::cast(context());
+ VisitForControl(expr->then_expression(),
+ for_test->true_label(),
+ for_test->false_label(),
+ NULL);
+ } else {
+ Visit(expr->then_expression());
__ jmp(&done);
}
Index: src/full-codegen.h
diff --git a/src/full-codegen.h b/src/full-codegen.h
index
9e126b848356b642f84b3c587c63bd795193f034..201507b2af338ea6e32b59d36c6a8cc145e22e0a
100644
--- a/src/full-codegen.h
+++ b/src/full-codegen.h
@@ -604,6 +604,15 @@ class FullCodeGenerator: public AstVisitor {
false_label_(false_label),
fall_through_(fall_through) { }
+ static const TestContext* cast(const ExpressionContext* context) {
+ ASSERT(context->IsTest());
+ return reinterpret_cast<const TestContext*>(context);
+ }
+
+ Label* true_label() const { return true_label_; }
+ Label* false_label() const { return false_label_; }
+ Label* fall_through() const { return fall_through_; }
+
virtual void Plug(bool flag) const;
virtual void Plug(Register reg) const;
virtual void Plug(Label* materialize_true, Label* materialize_false)
const;
--
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