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Refactor translation of short-circuit logical operations to avoid subgraphs.

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Do not use a subgraph or subgraph scope for the Hydrogen translation
of the short-circuit logical operations.

Review URL: http://codereview.chromium.org/6615010

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7045 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
kmillikin@chromium.org 2011-03-03 13:02:56 +00:00
parent f5839996fb
commit 84aceb526a
1 changed files with 11 additions and 16 deletions
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27
src/hydrogen.cc
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@ -4915,28 +4915,23 @@ void HGraphBuilder::VisitBinaryOperation(BinaryOperation* expr) {
VISIT_FOR_VALUE(expr->left());
ASSERT(current_block() != NULL);
HValue* left = Top();
HEnvironment* environment_copy = environment()->Copy();
environment_copy->Pop();
HSubgraph* right_subgraph;
right_subgraph = CreateBranchSubgraph(environment_copy);
ADD_TO_SUBGRAPH(right_subgraph, expr->right());
ASSERT(current_block() != NULL &&
right_subgraph->exit_block() != NULL);
// We need an extra block to maintain edge-split form.
HBasicBlock* empty_block = graph()->CreateBasicBlock();
HBasicBlock* join_block = graph()->CreateBasicBlock();
HBasicBlock* eval_right = graph()->CreateBasicBlock();
HTest* test = is_logical_and
? new HTest(left, right_subgraph->entry_block(), empty_block)
: new HTest(left, empty_block, right_subgraph->entry_block());
? new HTest(Top(), eval_right, empty_block)
: new HTest(Top(), empty_block, eval_right);
current_block()->Finish(test);
empty_block->Goto(join_block);
right_subgraph->exit_block()->Goto(join_block);
join_block->SetJoinId(expr->id());
set_current_block(eval_right);
Drop(1); // Value of the left subexpression.
VISIT_FOR_VALUE(expr->right());
HBasicBlock* join_block =
CreateJoin(empty_block, current_block(), expr->id());
set_current_block(join_block);
ast_context()->ReturnValue(Pop());
} else {
ASSERT(ast_context()->IsEffect());
// In an effect context, we don't need the value of the left