Factor out OSR-related graph-building functionality from hydrogen.cc.

src/hydrogen.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1888 matching lines @@
 
 
 HOptimizedGraphBuilder::HOptimizedGraphBuilder(CompilationInfo* info)
     : HGraphBuilder(info),
       function_state_(NULL),
       initial_function_state_(this, info, NORMAL_RETURN),
       ast_context_(NULL),
       break_scope_(NULL),
       inlined_count_(0),
       globals_(10, info->zone()),
-      inline_bailout_(false) {
+      inline_bailout_(false),
+      osr_(this) {
   // This is not initialized in the initializer list because the
   // constructor for the initial state relies on function_state_ == NULL
   // to know it's the initial state.
   function_state_= &initial_function_state_;
   InitializeAstVisitor();
 }
 
 
 HBasicBlock* HOptimizedGraphBuilder::CreateJoin(HBasicBlock* first,
                                                 HBasicBlock* second,
@@ skipping 47 matching lines @@
 
 
 HGraph::HGraph(CompilationInfo* info)
     : isolate_(info->isolate()),
       next_block_id_(0),
       entry_block_(NULL),
       blocks_(8, info->zone()),
       values_(16, info->zone()),
       phi_list_(NULL),
       uint32_instructions_(NULL),
+      osr_(NULL),
       info_(info),
       zone_(info->zone()),
       is_recursive_(false),
       use_optimistic_licm_(false),
       has_soft_deoptimize_(false),
       depends_on_empty_array_proto_elements_(false),
       type_change_checksum_(0),
       maximum_environment_size_(0) {
   if (info->IsStub()) {
     HydrogenCodeStub* stub = info->code_stub();
@@ skipping 1751 matching lines @@
   Handle<Code> unoptimized_code(current_info()->shared_info()->code());
   ASSERT(unoptimized_code->kind() == Code::FUNCTION);
   Handle<TypeFeedbackInfo> type_info(
       TypeFeedbackInfo::cast(unoptimized_code->type_feedback_info()));
   int checksum = type_info->own_type_change_checksum();
   int composite_checksum = graph()->update_type_change_checksum(checksum);
   graph()->set_use_optimistic_licm(
       !type_info->matches_inlined_type_change_checksum(composite_checksum));
   type_info->set_inlined_type_change_checksum(composite_checksum);
 
+  // Perform any necessary OSR-specific cleanups or changes to the graph.
+  osr_.FinishGraph();
+
   return true;
 }
 
 
 bool HGraph::Optimize(SmartArrayPointer<char>* bailout_reason) {
   *bailout_reason = SmartArrayPointer<char>();
   OrderBlocks();
   AssignDominators();
 
   // We need to create a HConstant "zero" now so that GVN will fold every
@@ skipping 23 matching lines @@
         "Unsupported phi use of arguments"));
     return false;
   }
 
   // Remove dead code and phis
   if (FLAG_dead_code_elimination) {
     DeadCodeElimination("H_Eliminate early dead code");
   }
   CollectPhis();
 
-  if (has_osr_loop_entry()) {
-    const ZoneList<HPhi*>* phis = osr_loop_entry()->phis();
-    for (int j = 0; j < phis->length(); j++) {
-      HPhi* phi = phis->at(j);
-      osr_values()->at(phi->merged_index())->set_incoming_value(phi);
-    }
-  }
+  if (has_osr()) osr()->FinishOsrValues();
 
   Run<HInferRepresentationPhase>();
 
   // Remove HSimulate instructions that have turned out not to be needed
   // after all by folding them into the following HSimulate.
   // This must happen after inferring representations.
   MergeRemovableSimulates();
 
   MarkDeoptimizeOnUndefined();
   InsertRepresentationChanges();
@@ skipping 1087 matching lines @@
                                  stmt->ExitId()));
   } else {
     if (fall_through_block != NULL) fall_through_block->Goto(break_block);
     if (last_block != NULL) last_block->Goto(break_block);
     break_block->SetJoinId(stmt->ExitId());
     set_current_block(break_block);
   }
 }
 
 
-bool HOptimizedGraphBuilder::HasOsrEntryAt(IterationStatement* statement) {
-  return statement->OsrEntryId() == current_info()->osr_ast_id();
-}
-
-
-bool HOptimizedGraphBuilder::PreProcessOsrEntry(IterationStatement* statement) {
-  if (!HasOsrEntryAt(statement)) return false;
-
-  HBasicBlock* non_osr_entry = graph()->CreateBasicBlock();
-  HBasicBlock* osr_entry = graph()->CreateBasicBlock();
-  HValue* true_value = graph()->GetConstantTrue();
-  HBranch* test = new(zone()) HBranch(true_value, non_osr_entry, osr_entry);
-  current_block()->Finish(test);
-
-  HBasicBlock* loop_predecessor = graph()->CreateBasicBlock();
-  non_osr_entry->Goto(loop_predecessor);
-
-  set_current_block(osr_entry);
-  osr_entry->set_osr_entry();
-  BailoutId osr_entry_id = statement->OsrEntryId();
-  int first_expression_index = environment()->first_expression_index();
-  int length = environment()->length();
-  ZoneList<HUnknownOSRValue*>* osr_values =
-      new(zone()) ZoneList<HUnknownOSRValue*>(length, zone());
-
-  for (int i = 0; i < first_expression_index; ++i) {
-    HUnknownOSRValue* osr_value = Add<HUnknownOSRValue>();
-    environment()->Bind(i, osr_value);
-    osr_values->Add(osr_value, zone());
-  }
-
-  if (first_expression_index != length) {
-    environment()->Drop(length - first_expression_index);
-    for (int i = first_expression_index; i < length; ++i) {
-      HUnknownOSRValue* osr_value = Add<HUnknownOSRValue>();
-      environment()->Push(osr_value);
-      osr_values->Add(osr_value, zone());
-    }
-  }
-
-  graph()->set_osr_values(osr_values);
-
-  AddSimulate(osr_entry_id);
-  Add<HOsrEntry>(osr_entry_id);
-  HContext* context = Add<HContext>();
-  environment()->BindContext(context);
-  current_block()->Goto(loop_predecessor);
-  loop_predecessor->SetJoinId(statement->EntryId());
-  set_current_block(loop_predecessor);
-  return true;
-}
-
-
 void HOptimizedGraphBuilder::VisitLoopBody(IterationStatement* stmt,
                                            HBasicBlock* loop_entry,
                                            BreakAndContinueInfo* break_info) {
   BreakAndContinueScope push(break_info, this);
   AddSimulate(stmt->StackCheckId());
   HValue* context = environment()->LookupContext();
   HStackCheck* stack_check = Add<HStackCheck>(
       context, HStackCheck::kBackwardsBranch);
   ASSERT(loop_entry->IsLoopHeader());
   loop_entry->loop_information()->set_stack_check(stack_check);
   CHECK_BAILOUT(Visit(stmt->body()));
 }
 
 
 void HOptimizedGraphBuilder::VisitDoWhileStatement(DoWhileStatement* stmt) {
   ASSERT(!HasStackOverflow());
   ASSERT(current_block() != NULL);
   ASSERT(current_block()->HasPredecessor());
   ASSERT(current_block() != NULL);
-  bool osr_entry = PreProcessOsrEntry(stmt);
-  HBasicBlock* loop_entry = CreateLoopHeaderBlock();
-  current_block()->Goto(loop_entry);
-  set_current_block(loop_entry);
-  if (osr_entry) graph()->set_osr_loop_entry(loop_entry);
+  HBasicBlock* loop_entry = osr_.BuildPossibleOsrLoopEntry(stmt);
 
   BreakAndContinueInfo break_info(stmt);
   CHECK_BAILOUT(VisitLoopBody(stmt, loop_entry, &break_info));
   HBasicBlock* body_exit =
       JoinContinue(stmt, current_block(), break_info.continue_block());
   HBasicBlock* loop_successor = NULL;
   if (body_exit != NULL && !stmt->cond()->ToBooleanIsTrue()) {
     set_current_block(body_exit);
     // The block for a true condition, the actual predecessor block of the
     // back edge.
@@ skipping 18 matching lines @@
                                       break_info.break_block());
   set_current_block(loop_exit);
 }
 
 
 void HOptimizedGraphBuilder::VisitWhileStatement(WhileStatement* stmt) {
   ASSERT(!HasStackOverflow());
   ASSERT(current_block() != NULL);
   ASSERT(current_block()->HasPredecessor());
   ASSERT(current_block() != NULL);
-  bool osr_entry = PreProcessOsrEntry(stmt);
-  HBasicBlock* loop_entry = CreateLoopHeaderBlock();
-  current_block()->Goto(loop_entry);
-  set_current_block(loop_entry);
-  if (osr_entry) graph()->set_osr_loop_entry(loop_entry);
-
+  HBasicBlock* loop_entry = osr_.BuildPossibleOsrLoopEntry(stmt);
 
   // If the condition is constant true, do not generate a branch.
   HBasicBlock* loop_successor = NULL;
   if (!stmt->cond()->ToBooleanIsTrue()) {
     HBasicBlock* body_entry = graph()->CreateBasicBlock();
     loop_successor = graph()->CreateBasicBlock();
     CHECK_BAILOUT(VisitForControl(stmt->cond(), body_entry, loop_successor));
     if (body_entry->HasPredecessor()) {
       body_entry->SetJoinId(stmt->BodyId());
       set_current_block(body_entry);
@@ skipping 21 matching lines @@
 
 
 void HOptimizedGraphBuilder::VisitForStatement(ForStatement* stmt) {
   ASSERT(!HasStackOverflow());
   ASSERT(current_block() != NULL);
   ASSERT(current_block()->HasPredecessor());
   if (stmt->init() != NULL) {
     CHECK_ALIVE(Visit(stmt->init()));
   }
   ASSERT(current_block() != NULL);
-  bool osr_entry = PreProcessOsrEntry(stmt);
-  HBasicBlock* loop_entry = CreateLoopHeaderBlock();
-  current_block()->Goto(loop_entry);
-  set_current_block(loop_entry);
-  if (osr_entry) graph()->set_osr_loop_entry(loop_entry);
+  HBasicBlock* loop_entry = osr_.BuildPossibleOsrLoopEntry(stmt);
 
   HBasicBlock* loop_successor = NULL;
   if (stmt->cond() != NULL) {
     HBasicBlock* body_entry = graph()->CreateBasicBlock();
     loop_successor = graph()->CreateBasicBlock();
     CHECK_BAILOUT(VisitForControl(stmt->cond(), body_entry, loop_successor));
     if (body_entry->HasPredecessor()) {
       body_entry->SetJoinId(stmt->BodyId());
       set_current_block(body_entry);
     }
@@ skipping 63 matching lines @@
   Push(map);
   Push(array);
   Push(enum_length);
   Push(start_index);
 
   HInstruction* index_cache = Add<HForInCacheArray>(
       enumerable, map, DescriptorArray::kEnumCacheBridgeIndicesCacheIndex);
   HForInCacheArray::cast(array)->set_index_cache(
       HForInCacheArray::cast(index_cache));
 
-  bool osr_entry = PreProcessOsrEntry(stmt);
-  HBasicBlock* loop_entry = CreateLoopHeaderBlock();
-  current_block()->Goto(loop_entry);
-  set_current_block(loop_entry);
-  if (osr_entry) graph()->set_osr_loop_entry(loop_entry);
+  HBasicBlock* loop_entry = osr_.BuildPossibleOsrLoopEntry(stmt);
 
   HValue* index = environment()->ExpressionStackAt(0);
   HValue* limit = environment()->ExpressionStackAt(1);
 
   // Check that we still have more keys.
   HCompareIDAndBranch* compare_index =
       new(zone()) HCompareIDAndBranch(index, limit, Token::LT);
   compare_index->set_observed_input_representation(
       Representation::Smi(), Representation::Smi());
 
@@ skipping 6071 matching lines @@
   if (ShouldProduceTraceOutput()) {
     isolate()->GetHTracer()->TraceHydrogen(name(), graph_);
   }
 
 #ifdef DEBUG
   graph_->Verify(false);  // No full verify.
 #endif
 }
 
 } }  // namespace v8::internal