Reviewers: Yang,
https://codereview.chromium.org/12281019/diff/1/src/hydrogen-instructions.cc
File src/hydrogen-instructions.cc (right):
https://codereview.chromium.org/12281019/diff/1/src/hydrogen-instructions.cc#newcode2749
src/hydrogen-instructions.cc:2749: new(zone)
HConstant(FACTORY->NewNumber(val, TENURED), \
On 2013/02/19 14:39:07, Yang wrote:
As discussed offline, there is no need to allocate in the double case
either.
Done.
Description:
Avoid creating unnecessary branches in Hydrogen
Please review this at https://codereview.chromium.org/12281019/
SVN Base: https://v8.googlecode.com/svn/branches/bleeding_edge
Affected files:
M src/hydrogen-instructions.cc
M src/hydrogen.cc
Index: src/hydrogen-instructions.cc
diff --git a/src/hydrogen-instructions.cc b/src/hydrogen-instructions.cc
index
2d4b82bf16ba1efe84bbc0915111921069ad9384..fceed3c5078494751ab7392c940c1004086c7fb3
100644
--- a/src/hydrogen-instructions.cc
+++ b/src/hydrogen-instructions.cc
@@ -2744,11 +2744,9 @@ bool HStoreKeyed::NeedsCanonicalization() {
#define
H_CONSTANT_INT32(val) \
-new(zone) HConstant(FACTORY->NewNumberFromInt(val,
TENURED), \
- Representation::Integer32())
+new(zone) HConstant(val, Representation::Integer32())
#define
H_CONSTANT_DOUBLE(val) \
-new(zone) HConstant(FACTORY->NewNumber(val,
TENURED), \
- Representation::Double())
+new(zone) HConstant(val, Representation::Double())
#define DEFINE_NEW_H_SIMPLE_ARITHMETIC_INSTR(HInstr,
op) \
HInstruction* HInstr::New##HInstr(Zone*
zone, \
@@ -2893,7 +2891,8 @@ HInstruction* HShr::NewHShr(Zone* zone,
return H_CONSTANT_DOUBLE(
static_cast<double>(static_cast<uint32_t>(left_val)));
}
- return H_CONSTANT_INT32(static_cast<uint32_t>(left_val) >>
right_val);
+ return H_CONSTANT_INT32(static_cast<int32_t>(
+ static_cast<uint32_t>(left_val) >> right_val));
}
}
return new(zone) HShr(context, left, right);
Index: src/hydrogen.cc
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index
62fa571bbcdcd2e29e687b5d2ffc4604979cbab8..5bda97d2187c4b78ef098eb8d40f7d72c725c45a
100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -3615,6 +3615,16 @@ void TestContext::BuildBranch(HValue* value) {
if (value != NULL && value->CheckFlag(HValue::kIsArguments)) {
builder->Bailout("arguments object value in a test context");
}
+ if (value->IsConstant()) {
+ HConstant* constant_value = HConstant::cast(value);
+ if (constant_value->ToBoolean()) {
+ builder->current_block()->Goto(if_true(), builder->function_state());
+ } else {
+ builder->current_block()->Goto(if_false(),
builder->function_state());
+ }
+ builder->set_current_block(NULL);
+ return;
+ }
HBasicBlock* empty_true = builder->graph()->CreateBasicBlock();
HBasicBlock* empty_false = builder->graph()->CreateBasicBlock();
TypeFeedbackId test_id = condition()->test_id();
@@ -3622,8 +3632,8 @@ void TestContext::BuildBranch(HValue* value) {
HBranch* test = new(zone()) HBranch(value, empty_true, empty_false,
expected);
builder->current_block()->Finish(test);
- empty_true->Goto(if_true(), owner()->function_state());
- empty_false->Goto(if_false(), owner()->function_state());
+ empty_true->Goto(if_true(), builder->function_state());
+ empty_false->Goto(if_false(), builder->function_state());
builder->set_current_block(NULL);
}
@@ -9032,6 +9042,17 @@ void
HOptimizedGraphBuilder::VisitLogicalExpression(BinaryOperation* expr) {
} else if (ast_context()->IsValue()) {
CHECK_ALIVE(VisitForValue(expr->left()));
ASSERT(current_block() != NULL);
+ HValue* left_value = Top();
+
+ if (left_value->IsConstant()) {
+ HConstant* left_constant = HConstant::cast(left_value);
+ if ((is_logical_and && left_constant->ToBoolean()) ||
+ (!is_logical_and && !left_constant->ToBoolean())) {
+ Drop(1); // left_value.
+ CHECK_BAILOUT(VisitForValue(expr->right()));
+ }
+ return ast_context()->ReturnValue(Pop());
+ }
// We need an extra block to maintain edge-split form.
HBasicBlock* empty_block = graph()->CreateBasicBlock();
@@ -9039,8 +9060,8 @@ void
HOptimizedGraphBuilder::VisitLogicalExpression(BinaryOperation* expr) {
TypeFeedbackId test_id = expr->left()->test_id();
ToBooleanStub::Types expected(oracle()->ToBooleanTypes(test_id));
HBranch* test = is_logical_and
- ? new(zone()) HBranch(Top(), eval_right, empty_block, expected)
- : new(zone()) HBranch(Top(), empty_block, eval_right, expected);
+ ? new(zone()) HBranch(left_value, eval_right, empty_block, expected)
+ : new(zone()) HBranch(left_value, empty_block, eval_right, expected);
current_block()->Finish(test);
set_current_block(eval_right);
--
--
v8-dev mailing list
[email protected]
http://groups.google.com/group/v8-dev
---
You received this message because you are subscribed to the Google Groups "v8-dev" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
For more options, visit https://groups.google.com/groups/opt_out.
