Adding visitors to regurgitate expression types or reset them.

src/typing-reset.cc

Index: src/typing-reset.cc
diff --git a/src/typing-reset.cc b/src/typing-reset.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b3b3aec573ecfd35bdeae93e3a4905598aedb087
--- /dev/null
+++ b/src/typing-reset.cc
@@ -0,0 +1,31 @@
+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "src/v8.h"
+
+#include "src/typing-reset.h"
+
+#include "src/ast.h"
+#include "src/codegen.h"
+#include "src/scopes.h"
+
+namespace v8 {
+namespace internal {
+
+
+TypingReseter::TypingReseter(CompilationInfo* info)
+    : AstExpressionVisitor(info), info_(info) {}
+
+
+void TypingReseter::Run(CompilationInfo* info) {
+  TypingReseter* visitor = new (info->zone()) TypingReseter(info);

[rossberg, 2015/08/20 16:34:26]

No need to heap-allocate the visitor, AFAICT.

[bradn, 2015/08/20 21:35:47]

Ok, changed round.

By the way, a terminology question.
You referred to this as heap-allocation, but I had the impression that usually
refers to allocation in V8's GC heap? Whereas isn't this just in a Zone scoped
to this particular compile? Or have I misunderstood something about Zones + GC
heap?

[rossberg, 2015/08/21 12:36:51]

I was just being sloppy. Meant heap-allocated as opposed to stack-allocated.

+  visitor->VisitAll();
+}
+
+
+void TypingReseter::VisitExpression(Expression* expression) {
+  expression->set_bounds(Bounds::Unbounded(info_->zone()));
+}
+}
+}  // namespace v8::internal