Reviewers: Kevin Millikin,
Description:
Mark HChange that convert to int32 with truncation with the appropiate flag.
Before we would compute the flag by iterating over all uses. The truncating
flag is always determined at construction time since we already computed
the flag for all other instructions before inserting HChange instructions.
Please review this at http://codereview.chromium.org/6615012/
SVN Base: http://v8.googlecode.com/svn/branches/bleeding_edge/
Affected files:
M src/hydrogen-instructions.h
M src/hydrogen.h
M src/hydrogen.cc
Index: src/hydrogen-instructions.h
===================================================================
--- src/hydrogen-instructions.h (revision 7039)
+++ src/hydrogen-instructions.h (working copy)
@@ -940,13 +940,14 @@
public:
HChange(HValue* value,
Representation from,
- Representation to)
+ Representation to,
+ bool is_truncating)
: HUnaryOperation(value), from_(from), to_(to) {
ASSERT(!from.IsNone() && !to.IsNone());
ASSERT(!from.Equals(to));
set_representation(to);
SetFlag(kUseGVN);
-
+ if (is_truncating) SetFlag(kTruncatingToInt32);
if (from.IsInteger32() && to.IsTagged() && value->range() != NULL &&
value->range()->IsInSmiRange()) {
set_type(HType::Smi());
@@ -961,12 +962,7 @@
return from_;
}
- bool CanTruncateToInt32() const {
- for (int i = 0; i < uses()->length(); ++i) {
- if (!uses()->at(i)->CheckFlag(HValue::kTruncatingToInt32)) return
false;
- }
- return true;
- }
+ bool CanTruncateToInt32() const { return CheckFlag(kTruncatingToInt32); }
virtual void PrintDataTo(StringStream* stream);
@@ -978,8 +974,7 @@
if (!other->IsChange()) return false;
HChange* change = HChange::cast(other);
return value() == change->value()
- && to().Equals(change->to())
- && CanTruncateToInt32() == change->CanTruncateToInt32();
+ && to().Equals(change->to());
}
private:
Index: src/hydrogen.cc
===================================================================
--- src/hydrogen.cc (revision 7039)
+++ src/hydrogen.cc (working copy)
@@ -1663,8 +1663,7 @@
void HGraph::InsertRepresentationChangeForUse(HValue* value,
HValue* use,
- Representation to,
- bool is_truncating) {
+ Representation to) {
// Insert the representation change right before its use. For phi-uses we
// insert at the end of the corresponding predecessor.
HInstruction* next = NULL;
@@ -1681,6 +1680,7 @@
// information we treat constants like normal instructions and insert the
// change instructions for them.
HInstruction* new_value = NULL;
+ bool is_truncating = use->CheckFlag(HValue::kTruncatingToInt32);
if (value->IsConstant()) {
HConstant* constant = HConstant::cast(value);
// Try to create a new copy of the constant with the new
representation.
@@ -1690,7 +1690,7 @@
}
if (new_value == NULL) {
- new_value = new HChange(value, value->representation(), to);
+ new_value = new HChange(value, value->representation(), to,
is_truncating);
}
new_value->InsertBefore(next);
@@ -1765,8 +1765,7 @@
for (int i = 0; i < to_convert.length(); ++i) {
HValue* use = to_convert[i];
Representation r_to = to_convert_reps[i];
- bool is_truncating = use->CheckFlag(HValue::kTruncatingToInt32);
- InsertRepresentationChangeForUse(current, use, r_to, is_truncating);
+ InsertRepresentationChangeForUse(current, use, r_to);
}
if (current->uses()->is_empty()) {
Index: src/hydrogen.h
===================================================================
--- src/hydrogen.h (revision 7039)
+++ src/hydrogen.h (working copy)
@@ -302,8 +302,7 @@
void PropagateMinusZeroChecks(HValue* value, BitVector* visited);
void InsertRepresentationChangeForUse(HValue* value,
HValue* use,
- Representation to,
- bool truncating);
+ Representation to);
void InsertRepresentationChanges(HValue* current);
void InferTypes(ZoneList<HValue*>* worklist);
void InitializeInferredTypes(int from_inclusive, int to_inclusive);
--
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