Reland "Keep a canonical list of shared function infos."

src/compiler/ast-graph-builder.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/ast-graph-builder.h"
 
 #include "src/compiler.h"
 #include "src/compiler/ast-loop-assignment-analyzer.h"
 #include "src/compiler/control-builders.h"
 #include "src/compiler/js-type-feedback.h"
@@ skipping 1077 matching lines @@
     case Variable::LOOKUP:
       UNIMPLEMENTED();
   }
 }
 
 
 void AstGraphBuilder::VisitFunctionDeclaration(FunctionDeclaration* decl) {
   Variable* variable = decl->proxy()->var();
   switch (variable->location()) {
     case Variable::UNALLOCATED: {
-      Handle<SharedFunctionInfo> function =
-          Compiler::BuildFunctionInfo(decl->fun(), info()->script(), info());
+      Handle<SharedFunctionInfo> function = Compiler::GetSharedFunctionInfo(
+          decl->fun(), info()->script(), info());
       // Check for stack-overflow exception.
       if (function.is_null()) return SetStackOverflow();
       globals()->push_back(variable->name());
       globals()->push_back(function);
       break;
     }
     case Variable::PARAMETER:
     case Variable::LOCAL: {
       VisitForValue(decl->fun());
       Node* value = environment()->Pop();
@@ skipping 402 matching lines @@
 void AstGraphBuilder::VisitDebuggerStatement(DebuggerStatement* stmt) {
   Node* node = NewNode(javascript()->CallRuntime(Runtime::kDebugBreak, 0));
   PrepareFrameState(node, stmt->DebugBreakId());
   environment()->MarkAllLocalsLive();
 }
 
 
 void AstGraphBuilder::VisitFunctionLiteral(FunctionLiteral* expr) {
   Node* context = current_context();
 
-  // Build a new shared function info if we cannot find one in the baseline
-  // code. We also have a stack overflow if the recursive compilation did.
-  expr->InitializeSharedInfo(handle(info()->shared_info()->code()));
-  Handle<SharedFunctionInfo> shared_info = expr->shared_info();
-  if (shared_info.is_null()) {
-    shared_info = Compiler::BuildFunctionInfo(expr, info()->script(), info());
-    CHECK(!shared_info.is_null());  // TODO(mstarzinger): Set stack overflow?
-  }
+  // Find or build a shared function info.
+  Handle<SharedFunctionInfo> shared_info =
+      Compiler::GetSharedFunctionInfo(expr, info()->script(), info());
+  CHECK(!shared_info.is_null());  // TODO(mstarzinger): Set stack overflow?
 
   // Create node to instantiate a new closure.
   PretenureFlag pretenure = expr->pretenure() ? TENURED : NOT_TENURED;
   const Operator* op = javascript()->CreateClosure(shared_info, pretenure);
   Node* value = NewNode(op, context);
   ast_context()->ProduceValue(value);
 }
 
 
 void AstGraphBuilder::VisitClassLiteral(ClassLiteral* expr) {
@@ skipping 2622 matching lines @@
     // Phi does not exist yet, introduce one.
     value = NewPhi(inputs, value, control);
     value->ReplaceInput(inputs - 1, other);
   }
   return value;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8