[interpreter] Make it possible to optimize without parse.

This makes sure we can run through the TurboFan pipeline without having
to parse the source when using the bytecode stream as input. This path
is now being tested by the BytecodeGraphTester helper.

R=titzer@chromium.org,rmcilroy@chromium.org

Review URL: https://codereview.chromium.org/1679313002

Cr-Commit-Position: refs/heads/master@{#33856}

src/compiler.cc

@@ -279,10 +279,13 @@ void CompilationInfo::LogDeoptCallPosition(int pc_offset, int inlining_id) {
 
 
 base::SmartArrayPointer<char> CompilationInfo::GetDebugName() const {
-  if (parse_info()) {
+  if (parse_info() && parse_info()->literal()) {
     AllowHandleDereference allow_deref;
     return parse_info()->literal()->debug_name()->ToCString();
   }
+  if (parse_info() && !parse_info()->shared_info().is_null()) {
+    return parse_info()->shared_info()->DebugName()->ToCString();
+  }
   const char* str = debug_name_ ? debug_name_ : "unknown";
   size_t len = strlen(str) + 1;
   base::SmartArrayPointer<char> name(new char[len]);

src/compiler/pipeline.cc

@@ -1078,13 +1078,14 @@ Handle<Code> Pipeline::GenerateCode() {
     if (json_file != nullptr) {
       OFStream json_of(json_file);
       Handle<Script> script = info()->script();
-      FunctionLiteral* function = info()->literal();
       base::SmartArrayPointer<char> function_name = info()->GetDebugName();
       int pos = info()->shared_info()->start_position();
       json_of << "{\"function\":\"" << function_name.get()
               << "\", \"sourcePosition\":" << pos << ", \"source\":\"";
-      if (!script->IsUndefined() && !script->source()->IsUndefined()) {
+      if (info()->has_literal() && !script->IsUndefined() &&
+          !script->source()->IsUndefined()) {
         DisallowHeapAllocation no_allocation;
+        FunctionLiteral* function = info()->literal();
         int start = function->start_position();
         int len = function->end_position() - start;
         String::SubStringRange source(String::cast(script->source()), start,

test/cctest/compiler/test-run-bytecode-graph-builder.cc

@@ -70,6 +70,7 @@ class BytecodeGraphTester {
     i::FLAG_ignition = true;
     i::FLAG_always_opt = false;
     i::FLAG_allow_natives_syntax = true;
+    i::FLAG_loop_assignment_analysis = false;
     // Set ignition filter flag via SetFlagsFromString to avoid double-free
     // (or potential leak with StrDup() based on ownership confusion).
     ScopedVector<char> ignition_filter(64);
@@ -118,13 +119,13 @@ class BytecodeGraphTester {
         Handle<JSFunction>::cast(v8::Utils::OpenHandle(*api_function));
     CHECK(function->shared()->HasBytecodeArray());
 
+    // TODO(mstarzinger): We should be able to prime CompilationInfo without
+    // having to instantiate a ParseInfo first. Fix this!
     ParseInfo parse_info(zone_, function);
 
     CompilationInfo compilation_info(&parse_info);
     compilation_info.SetOptimizing(BailoutId::None(), Handle<Code>());
     compilation_info.MarkAsDeoptimizationEnabled();
-    // TODO(mythria): Remove this step once parse_info is not needed.
-    CHECK(Compiler::ParseAndAnalyze(&parse_info));
     compiler::Pipeline pipeline(&compilation_info);
     Handle<Code> code = pipeline.GenerateCode();
     function->ReplaceCode(*code);