AuroraMiddleware/v8
1
0
Fork 0
Code Issues 2 Pull Requests Releases Wiki Activity

Partial refactoring of subgraphs.

Browse Source 
Change the interface to the Hydrogen graph builder to appear like it
directly holds a current basic block and a current environment.
Remove some direct accesses to the current subgraph, and remove
subgraph accessors that simply forwarded to the exit block.

Review URL: http://codereview.chromium.org/6532088

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6887 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
kmillikin@chromium.org 2011-02-22 10:32:16 +00:00
parent b0fa94777e
commit 3c02d036a8
2 changed files with 100 additions and 88 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

159
src/hydrogen.cc
View File

@ -485,16 +485,17 @@ HConstant* HGraph::GetConstantFalse() {
void HSubgraph::AppendJoin(HSubgraph* then_graph,
HSubgraph* else_graph,
AstNode* node) {
if (then_graph->HasExit() && else_graph->HasExit()) {
if (then_graph->exit_block() != NULL &&
else_graph->exit_block() != NULL) {
// We need to merge, create new merge block.
HBasicBlock* join_block = graph_->CreateBasicBlock();
then_graph->exit_block()->Goto(join_block);
else_graph->exit_block()->Goto(join_block);
join_block->SetJoinId(node->id());
exit_block_ = join_block;
} else if (then_graph->HasExit()) {
} else if (then_graph->exit_block() != NULL) {
exit_block_ = then_graph->exit_block_;
} else if (else_graph->HasExit()) {
} else if (else_graph->exit_block() != NULL) {
exit_block_ = else_graph->exit_block_;
} else {
exit_block_ = NULL;
@ -526,8 +527,12 @@ HBasicBlock* HSubgraph::JoinBlocks(HBasicBlock* a, HBasicBlock* b, int id) {
void HSubgraph::AppendEndless(HSubgraph* body,
IterationStatement* statement,
HBasicBlock* break_block) {
ConnectExitTo(body->entry_block());
body->ConnectExitTo(body->entry_block(), true);
if (exit_block() != NULL) {
exit_block()->Goto(body->entry_block(), false);
}
if (body->exit_block() != NULL) {
body->exit_block()->Goto(body->entry_block(), true);
}
if (break_block != NULL) break_block->SetJoinId(statement->ExitId());
exit_block_ = break_block;
body->entry_block()->PostProcessLoopHeader(statement);
@ -539,8 +544,12 @@ void HSubgraph::AppendDoWhile(HSubgraph* body,
HSubgraph* go_back,
HSubgraph* exit,
HBasicBlock* break_block) {
ConnectExitTo(body->entry_block());
go_back->ConnectExitTo(body->entry_block(), true);
if (exit_block() != NULL) {
exit_block()->Goto(body->entry_block(), false);
}
if (go_back->exit_block() != NULL) {
go_back->exit_block()->Goto(body->entry_block(), true);
}
if (break_block != NULL) break_block->SetJoinId(statement->ExitId());
exit_block_ =
JoinBlocks(exit->exit_block(), break_block, statement->ExitId());
@ -554,20 +563,26 @@ void HSubgraph::AppendWhile(HSubgraph* condition,
HSubgraph* continue_subgraph,
HSubgraph* exit,
HBasicBlock* break_block) {
ConnectExitTo(condition->entry_block());
if (exit_block() != NULL) {
exit_block()->Goto(condition->entry_block(), false);
}
if (break_block != NULL) break_block->SetJoinId(statement->ExitId());
exit_block_ =
JoinBlocks(exit->exit_block(), break_block, statement->ExitId());
if (continue_subgraph != NULL) {
body->ConnectExitTo(continue_subgraph->entry_block(), true);
if (body->exit_block() != NULL) {
body->exit_block()->Goto(continue_subgraph->entry_block(), true);
}
continue_subgraph->entry_block()->SetJoinId(statement->EntryId());
exit_block_ = JoinBlocks(exit_block_,
continue_subgraph->exit_block(),
statement->ExitId());
} else {
body->ConnectExitTo(condition->entry_block(), true);
if (body->exit_block() != NULL) {
body->exit_block()->Goto(condition->entry_block(), true);
}
}
condition->entry_block()->PostProcessLoopHeader(statement);
}
@ -588,7 +603,7 @@ void HSubgraph::Append(HSubgraph* next,
void HSubgraph::FinishExit(HControlInstruction* instruction) {
ASSERT(HasExit());
ASSERT(exit_block() != NULL);
exit_block_->Finish(instruction);
exit_block_->ClearEnvironment();
exit_block_ = NULL;
@ -1936,14 +1951,14 @@ AstContext::~AstContext() {
EffectContext::~EffectContext() {
ASSERT(owner()->HasStackOverflow() ||
!owner()->subgraph()->HasExit() ||
owner()->current_block() == NULL ||
owner()->environment()->length() == original_length_);
}
ValueContext::~ValueContext() {
ASSERT(owner()->HasStackOverflow() ||
!owner()->subgraph()->HasExit() ||
owner()->current_block() == NULL ||
owner()->environment()->length() == original_length_ + 1);
}
@ -2001,7 +2016,7 @@ void TestContext::BuildBranch(HValue* value) {
HBasicBlock* empty_true = builder->graph()->CreateBasicBlock();
HBasicBlock* empty_false = builder->graph()->CreateBasicBlock();
HTest* test = new HTest(value, empty_true, empty_false);
builder->CurrentBlock()->Finish(test);
builder->current_block()->Finish(test);
HValue* const no_return_value = NULL;
HBasicBlock* true_target = if_true();
@ -2017,7 +2032,7 @@ void TestContext::BuildBranch(HValue* value) {
} else {
empty_false->Goto(false_target);
}
builder->subgraph()->set_exit_block(NULL);
builder->set_current_block(NULL);
}
@ -2124,7 +2139,7 @@ void HGraphBuilder::VisitArgument(Expression* expr) {
void HGraphBuilder::VisitArgumentList(ZoneList<Expression*>* arguments) {
for (int i = 0; i < arguments->length(); i++) {
VisitArgument(arguments->at(i));
if (HasStackOverflow() || !current_subgraph_->HasExit()) return;
if (HasStackOverflow() || current_block() == NULL) return;
}
}
@ -2158,7 +2173,7 @@ HGraph* HGraphBuilder::CreateGraph(CompilationInfo* info) {
current_subgraph_->Append(body, NULL, NULL);
body->entry_block()->SetJoinId(info->function()->id());
if (graph_->HasExit()) {
if (graph()->exit_block() != NULL) {
graph_->FinishExit(new HReturn(graph_->GetConstantUndefined()));
}
}
@ -2219,21 +2234,21 @@ void HGraphBuilder::AddToSubgraph(HSubgraph* graph,
HInstruction* HGraphBuilder::AddInstruction(HInstruction* instr) {
ASSERT(current_subgraph_->HasExit());
current_subgraph_->exit_block()->AddInstruction(instr);
ASSERT(current_block() != NULL);
current_block()->AddInstruction(instr);
return instr;
}
void HGraphBuilder::AddSimulate(int id) {
ASSERT(current_subgraph_->HasExit());
current_subgraph_->exit_block()->AddSimulate(id);
ASSERT(current_block() != NULL);
current_block()->AddSimulate(id);
}
void HGraphBuilder::AddPhi(HPhi* instr) {
ASSERT(current_subgraph_->HasExit());
current_subgraph_->exit_block()->AddPhi(instr);
ASSERT(current_block() != NULL);
current_block()->AddPhi(instr);
}
@ -2296,7 +2311,7 @@ void HGraphBuilder::SetupScope(Scope* scope) {
void HGraphBuilder::VisitStatements(ZoneList<Statement*>* statements) {
for (int i = 0; i < statements->length(); i++) {
Visit(statements->at(i));
if (HasStackOverflow() || !current_subgraph_->HasExit()) break;
if (HasStackOverflow() || current_block() == NULL) break;
}
}
@ -2435,15 +2450,15 @@ HBasicBlock* HGraphBuilder::BreakAndContinueScope::Get(
void HGraphBuilder::VisitContinueStatement(ContinueStatement* stmt) {
HBasicBlock* continue_block = break_scope()->Get(stmt->target(), CONTINUE);
subgraph()->exit_block()->Goto(continue_block);
subgraph()->set_exit_block(NULL);
current_block()->Goto(continue_block);
set_current_block(NULL);
}
void HGraphBuilder::VisitBreakStatement(BreakStatement* stmt) {
HBasicBlock* break_block = break_scope()->Get(stmt->target(), BREAK);
subgraph()->exit_block()->Goto(break_block);
subgraph()->set_exit_block(NULL);
current_block()->Goto(break_block);
set_current_block(NULL);
}
@ -2472,9 +2487,9 @@ void HGraphBuilder::VisitReturnStatement(ReturnStatement* stmt) {
VISIT_FOR_VALUE(stmt->expression());
return_value = environment()->Pop();
}
subgraph()->exit_block()->AddLeaveInlined(return_value,
current_block()->AddLeaveInlined(return_value,
function_return_);
subgraph()->set_exit_block(NULL);
set_current_block(NULL);
}
}
}
@ -2495,7 +2510,7 @@ HCompare* HGraphBuilder::BuildSwitchCompare(HSubgraph* subgraph,
CaseClause* clause) {
AddToSubgraph(subgraph, clause->label());
if (HasStackOverflow()) return NULL;
HValue* clause_value = subgraph->environment()->Pop();
HValue* clause_value = subgraph->exit_block()->last_environment()->Pop();
HCompare* compare = new HCompare(switch_value,
clause_value,
Token::EQ_STRICT);
@ -2576,7 +2591,7 @@ void HGraphBuilder::VisitSwitchStatement(SwitchStatement* stmt) {
// last_false_block is the (empty) false-block of the last comparison. If
// there are no comparisons at all (a single default clause), it is just
// the last block of the current subgraph.
HBasicBlock* last_false_block = current_subgraph_->exit_block();
HBasicBlock* last_false_block = current_block();
if (prev_graph != current_subgraph_) {
last_false_block = graph()->CreateBasicBlock();
HBasicBlock* empty = graph()->CreateBasicBlock();
@ -2619,7 +2634,7 @@ void HGraphBuilder::VisitSwitchStatement(SwitchStatement* stmt) {
}
// Check for fall-through from previous statement block.
if (previous_subgraph != NULL && previous_subgraph->HasExit()) {
if (previous_subgraph != NULL && previous_subgraph->exit_block() != NULL) {
if (subgraph == NULL) subgraph = CreateEmptySubgraph();
previous_subgraph->exit_block()->
Finish(new HGoto(subgraph->entry_block()));
@ -2641,7 +2656,7 @@ void HGraphBuilder::VisitSwitchStatement(SwitchStatement* stmt) {
// If the last statement block has a fall-through, connect it to the
// single exit block.
if (previous_subgraph != NULL && previous_subgraph->HasExit()) {
if (previous_subgraph != NULL && previous_subgraph->exit_block() != NULL) {
previous_subgraph->exit_block()->Finish(new HGoto(single_exit_block));
}
@ -2651,9 +2666,9 @@ void HGraphBuilder::VisitSwitchStatement(SwitchStatement* stmt) {
}
if (single_exit_block->HasPredecessor()) {
current_subgraph_->set_exit_block(single_exit_block);
set_current_block(single_exit_block);
} else {
current_subgraph_->set_exit_block(NULL);
set_current_block(NULL);
}
}
@ -2695,7 +2710,7 @@ void HSubgraph::PreProcessOsrEntry(IterationStatement* statement) {
void HGraphBuilder::VisitDoWhileStatement(DoWhileStatement* stmt) {
ASSERT(subgraph()->HasExit());
ASSERT(current_block() != NULL);
subgraph()->PreProcessOsrEntry(stmt);
HSubgraph* body_graph = CreateLoopHeaderSubgraph(environment());
@ -2705,7 +2720,7 @@ void HGraphBuilder::VisitDoWhileStatement(DoWhileStatement* stmt) {
}
body_graph->ResolveContinue(stmt, break_info.continue_block());
if (!body_graph->HasExit() || stmt->cond()->ToBooleanIsTrue()) {
if (body_graph->exit_block() == NULL || stmt->cond()->ToBooleanIsTrue()) {
subgraph()->AppendEndless(body_graph, stmt, break_info.break_block());
} else {
HSubgraph* go_back = CreateEmptySubgraph();
@ -2730,7 +2745,7 @@ bool HGraphBuilder::ShouldPeel(HSubgraph* cond, HSubgraph* body) {
void HGraphBuilder::VisitWhileStatement(WhileStatement* stmt) {
ASSERT(subgraph()->HasExit());
ASSERT(current_block() != NULL);
subgraph()->PreProcessOsrEntry(stmt);
HSubgraph* cond_graph = NULL;
@ -2776,12 +2791,12 @@ void HGraphBuilder::AppendPeeledWhile(IterationStatement* stmt,
HSubgraph* exit_graph,
HBasicBlock* break_block) {
HSubgraph* loop = NULL;
if (body_graph->HasExit() && stmt != peeled_statement_ &&
if (body_graph->exit_block() != NULL && stmt != peeled_statement_ &&
ShouldPeel(cond_graph, body_graph)) {
// Save the last peeled iteration statement to prevent infinite recursion.
IterationStatement* outer_peeled_statement = peeled_statement_;
peeled_statement_ = stmt;
loop = CreateGotoSubgraph(body_graph->environment());
loop = CreateGotoSubgraph(body_graph->exit_block()->last_environment());
ADD_TO_SUBGRAPH(loop, stmt);
peeled_statement_ = outer_peeled_statement;
}
@ -2796,7 +2811,7 @@ void HGraphBuilder::VisitForStatement(ForStatement* stmt) {
Visit(stmt->init());
CHECK_BAILOUT;
}
ASSERT(subgraph()->HasExit());
ASSERT(current_block() != NULL);
subgraph()->PreProcessOsrEntry(stmt);
HSubgraph* cond_graph = NULL;
@ -2825,8 +2840,9 @@ void HGraphBuilder::VisitForStatement(ForStatement* stmt) {
HSubgraph* next_graph = NULL;
body_graph->ResolveContinue(stmt, break_info.continue_block());
if (stmt->next() != NULL && body_graph->HasExit()) {
next_graph = CreateGotoSubgraph(body_graph->environment());
if (stmt->next() != NULL && body_graph->exit_block() != NULL) {
next_graph =
CreateGotoSubgraph(body_graph->exit_block()->last_environment());
ADD_TO_SUBGRAPH(next_graph, stmt->next());
body_graph->Append(next_graph, NULL, NULL);
next_graph->entry_block()->SetJoinId(stmt->ContinueId());
@ -3103,9 +3119,9 @@ HBasicBlock* HGraphBuilder::BuildTypeSwitch(HValue* receiver,
maps->at(i),
if_true->entry_block(),
if_false->entry_block());
subgraph()->exit_block()->Finish(compare);
current_block()->Finish(compare);
if (if_true->HasExit()) {
if (if_true->exit_block() != NULL) {
// In an effect context the value of the type switch is not needed.
// There is no need to merge it at the join block only to discard it.
if (ast_context()->IsEffect()) {
@ -3114,15 +3130,15 @@ HBasicBlock* HGraphBuilder::BuildTypeSwitch(HValue* receiver,
if_true->exit_block()->Goto(join_block);
}
subgraph()->set_exit_block(if_false->exit_block());
set_current_block(if_false->exit_block());
}
// Connect the default if necessary.
if (subgraph()->HasExit()) {
if (current_block() != NULL) {
if (ast_context()->IsEffect()) {
environment()->Drop(1);
}
subgraph()->exit_block()->Goto(join_block);
current_block()->Goto(join_block);
}
if (join_block->predecessors()->is_empty()) return NULL;
@ -3279,10 +3295,10 @@ void HGraphBuilder::HandlePolymorphicStoreNamedField(Assignment* expr,
HBasicBlock* new_exit_block =
BuildTypeSwitch(object, &maps, &subgraphs, default_graph, expr->id());
subgraph()->set_exit_block(new_exit_block);
set_current_block(new_exit_block);
// In an effect context, we did not materialized the value in the
// predecessor environments so there's no need to handle it here.
if (subgraph()->HasExit() && !ast_context()->IsEffect()) {
if (current_block() != NULL && !ast_context()->IsEffect()) {
ast_context()->ReturnValue(Pop());
}
}
@ -3613,10 +3629,10 @@ void HGraphBuilder::HandlePolymorphicLoadNamedField(Property* expr,
HBasicBlock* new_exit_block =
BuildTypeSwitch(object, &maps, &subgraphs, default_graph, expr->id());
subgraph()->set_exit_block(new_exit_block);
set_current_block(new_exit_block);
// In an effect context, we did not materialized the value in the
// predecessor environments so there's no need to handle it here.
if (subgraph()->HasExit() && !ast_context()->IsEffect()) {
if (current_block() != NULL && !ast_context()->IsEffect()) {
ast_context()->ReturnValue(Pop());
}
}
@ -3973,7 +3989,7 @@ void HGraphBuilder::HandlePolymorphicCallNamed(Call* expr,
HBasicBlock* new_exit_block =
BuildTypeSwitch(receiver, &maps, &subgraphs, default_graph, expr->id());
subgraph()->set_exit_block(new_exit_block);
set_current_block(new_exit_block);
// In an effect context, we did not materialized the value in the
// predecessor environments so there's no need to handle it here.
if (new_exit_block != NULL && !ast_context()->IsEffect()) {
@ -4142,7 +4158,7 @@ bool HGraphBuilder::TryInline(Call* expr) {
if (FLAG_trace_inlining) TraceInline(target, true);
if (body->HasExit()) {
if (body->exit_block() != NULL) {
// Add a return of undefined if control can fall off the body. In a
// test context, undefined is false.
HValue* return_value = graph()->GetConstantUndefined();
@ -4171,7 +4187,7 @@ bool HGraphBuilder::TryInline(Call* expr) {
AddSimulate(expr->ReturnId());
// Jump to the function entry (without re-recording the environment).
subgraph()->exit_block()->Finish(new HGoto(body->entry_block()));
current_block()->Finish(new HGoto(body->entry_block()));
// Fix up the function exits.
if (test_context != NULL) {
@ -4201,11 +4217,11 @@ bool HGraphBuilder::TryInline(Call* expr) {
// TODO(kmillikin): Come up with a better way to handle this. It is too
// subtle. NULL here indicates that the enclosing context has no control
// flow to handle.
subgraph()->set_exit_block(NULL);
set_current_block(NULL);
} else {
function_return_->SetJoinId(expr->id());
subgraph()->set_exit_block(function_return_);
set_current_block(function_return_);
}
call_context_ = saved_call_context;
@ -4434,7 +4450,7 @@ void HGraphBuilder::VisitCall(Call* expr) {
AddCheckConstantFunction(expr, receiver, receiver_map, true);
if (TryInline(expr)) {
if (subgraph()->HasExit()) {
if (current_block() != NULL) {
HValue* return_value = Pop();
// If we inlined a function in a test context then we need to emit
// a simulate here to shadow the ones at the end of the
@ -4505,7 +4521,7 @@ void HGraphBuilder::VisitCall(Call* expr) {
environment()->SetExpressionStackAt(receiver_index, global_receiver);
if (TryInline(expr)) {
if (subgraph()->HasExit()) {
if (current_block() != NULL) {
HValue* return_value = Pop();
// If we inlined a function in a test context then we need to
// emit a simulate here to shadow the ones at the end of the
@ -4673,10 +4689,12 @@ void HGraphBuilder::VisitUnaryOperation(UnaryOperation* expr) {
false_graph->entry_block(),
true_graph->entry_block());
true_graph->entry_block()->SetJoinId(expr->expression()->id());
true_graph->environment()->Push(graph_->GetConstantTrue());
true_graph->exit_block()->last_environment()->Push(
graph_->GetConstantTrue());
false_graph->entry_block()->SetJoinId(expr->expression()->id());
false_graph->environment()->Push(graph_->GetConstantFalse());
false_graph->exit_block()->last_environment()->Push(
graph_->GetConstantFalse());
current_subgraph_->AppendJoin(true_graph, false_graph, expr);
ast_context()->ReturnValue(Pop());
@ -4973,12 +4991,12 @@ void HGraphBuilder::VisitBinaryOperation(BinaryOperation* expr) {
// Translate right subexpression by visiting it in the same AST
// context as the entire expression.
subgraph()->set_exit_block(eval_right);
set_current_block(eval_right);
Visit(expr->right());
} else if (ast_context()->IsValue()) {
VISIT_FOR_VALUE(expr->left());
ASSERT(current_subgraph_->HasExit());
ASSERT(current_block() != NULL);
HValue* left = Top();
HEnvironment* environment_copy = environment()->Copy();
@ -4987,7 +5005,8 @@ void HGraphBuilder::VisitBinaryOperation(BinaryOperation* expr) {
right_subgraph = CreateBranchSubgraph(environment_copy);
ADD_TO_SUBGRAPH(right_subgraph, expr->right());
ASSERT(subgraph()->HasExit() && right_subgraph->HasExit());
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();
@ -4995,11 +5014,11 @@ void HGraphBuilder::VisitBinaryOperation(BinaryOperation* expr) {
HTest* test = is_logical_and
? new HTest(left, right_subgraph->entry_block(), empty_block)
: new HTest(left, empty_block, right_subgraph->entry_block());
subgraph()->exit_block()->Finish(test);
current_block()->Finish(test);
empty_block->Goto(join_block);
right_subgraph->exit_block()->Goto(join_block);
join_block->SetJoinId(expr->id());
subgraph()->set_exit_block(join_block);
set_current_block(join_block);
ast_context()->ReturnValue(Pop());
} else {
ASSERT(ast_context()->IsEffect());
@ -5021,13 +5040,13 @@ void HGraphBuilder::VisitBinaryOperation(BinaryOperation* expr) {
// no good AST ID to put on that first HSimulate.
empty_block->SetJoinId(expr->id());
right_block->SetJoinId(expr->RightId());
subgraph()->set_exit_block(right_block);
set_current_block(right_block);
VISIT_FOR_EFFECT(expr->right());
empty_block->Goto(join_block);
subgraph()->exit_block()->Goto(join_block);
current_block()->Goto(join_block);
join_block->SetJoinId(expr->id());
subgraph()->set_exit_block(join_block);
set_current_block(join_block);
// We did not materialize any value in the predecessor environments,
// so there is no need to handle it here.
}

29
src/hydrogen.h
View File

@ -200,13 +200,12 @@ class HSubgraph: public ZoneObject {
}
HGraph* graph() const { return graph_; }
HEnvironment* environment() const {
ASSERT(HasExit());
return exit_block_->last_environment();
HBasicBlock* entry_block() const { return entry_block_; }
HBasicBlock* exit_block() const { return exit_block_; }
void set_exit_block(HBasicBlock* block) {
exit_block_ = block;
}
bool HasExit() const { return exit_block_ != NULL; }
void PreProcessOsrEntry(IterationStatement* statement);
void AppendJoin(HSubgraph* then_graph, HSubgraph* else_graph, AstNode* node);
@ -237,17 +236,6 @@ class HSubgraph: public ZoneObject {
entry_block_ = block;
exit_block_ = block;
}
HBasicBlock* entry_block() const { return entry_block_; }
HBasicBlock* exit_block() const { return exit_block_; }
void set_exit_block(HBasicBlock* block) {
exit_block_ = block;
}
void ConnectExitTo(HBasicBlock* other, bool include_stack_check = false) {
if (HasExit()) {
exit_block()->Goto(other, include_stack_check);
}
}
protected:
HGraph* graph_; // The graph this is a subgraph of.
@ -657,8 +645,13 @@ class HGraphBuilder: public AstVisitor {
BreakAndContinueScope* break_scope() const { return break_scope_; }
void set_break_scope(BreakAndContinueScope* head) { break_scope_ = head; }
HEnvironment* environment() const { return subgraph()->environment(); }
HBasicBlock* CurrentBlock() const { return subgraph()->exit_block(); }
HBasicBlock* current_block() const { return subgraph()->exit_block(); }
void set_current_block(HBasicBlock* block) {
subgraph()->set_exit_block(block);
}
HEnvironment* environment() const {
return current_block()->last_environment();
}
// Adding instructions.
HInstruction* AddInstruction(HInstruction* instr);