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

src/compiler/ast-graph-builder.cc

Index: src/compiler/ast-graph-builder.cc
diff --git a/src/compiler/ast-graph-builder.cc b/src/compiler/ast-graph-builder.cc
index 1147f85a6377c5978b39a5701438d789779b1aab..4de9a6434d1e6f5adaa983ca663c9fd4c098ef19 100644
--- a/src/compiler/ast-graph-builder.cc
+++ b/src/compiler/ast-graph-builder.cc
@@ -1095,8 +1095,8 @@ 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());
@@ -1519,14 +1519,10 @@ void AstGraphBuilder::VisitDebuggerStatement(DebuggerStatement* stmt) {
 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;