[turbofan] Add new JSFrameSpecialization reducer.

src/runtime/runtime-compiler.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/v8.h"
 
 #include "src/arguments.h"
 #include "src/compiler.h"
 #include "src/deoptimizer.h"
 #include "src/frames.h"
@@ skipping 201 matching lines @@
 #ifdef DEBUG
   DCHECK_EQ(frame->function(), *function);
   DCHECK_EQ(frame->LookupCode(), *caller_code);
   DCHECK(caller_code->contains(frame->pc()));
 #endif  // DEBUG
 
 
   BailoutId ast_id = caller_code->TranslatePcOffsetToAstId(pc_offset);
   DCHECK(!ast_id.IsNone());
 
-  Compiler::ConcurrencyMode mode =
-      isolate->concurrent_osr_enabled() &&
-              (function->shared()->ast_node_count() > 512)
-          ? Compiler::CONCURRENT
-          : Compiler::NOT_CONCURRENT;
+  // Disable concurrent OSR for asm.js, to enable frame specialization.
+  Compiler::ConcurrencyMode mode = (isolate->concurrent_osr_enabled() &&
+                                    !function->shared()->asm_function() &&
+                                    function->shared()->ast_node_count() > 512)
+                                       ? Compiler::CONCURRENT
+                                       : Compiler::NOT_CONCURRENT;
   Handle<Code> result = Handle<Code>::null();
 
   OptimizedCompileJob* job = NULL;
   if (mode == Compiler::CONCURRENT) {
     // Gate the OSR entry with a stack check.
     BackEdgeTable::AddStackCheck(caller_code, pc_offset);
     // Poll already queued compilation jobs.
     OptimizingCompileDispatcher* dispatcher =
         isolate->optimizing_compile_dispatcher();
     if (dispatcher->IsQueuedForOSR(function, ast_id)) {
@@ skipping 14 matching lines @@
       function->PrintName();
       PrintF(" at AST id %d]\n", ast_id.ToInt());
     }
     result = Compiler::GetConcurrentlyOptimizedCode(job);
   } else if (IsSuitableForOnStackReplacement(isolate, function)) {
     if (FLAG_trace_osr) {
       PrintF("[OSR - Compiling: ");
       function->PrintName();
       PrintF(" at AST id %d]\n", ast_id.ToInt());
     }
-    MaybeHandle<Code> maybe_result =
-        Compiler::GetOptimizedCode(function, caller_code, mode, ast_id);
+    MaybeHandle<Code> maybe_result = Compiler::GetOptimizedCode(
+        function, caller_code, mode, ast_id,
+        (mode == Compiler::NOT_CONCURRENT) ? frame : nullptr);
     if (maybe_result.ToHandle(&result) &&
         result.is_identical_to(isolate->builtins()->InOptimizationQueue())) {
       // Optimization is queued.  Return to check later.
       return NULL;
     }
   }
 
   // Revert the patched back edge table, regardless of whether OSR succeeds.
   BackEdgeTable::Revert(isolate, *caller_code);
 
@@ skipping 161 matching lines @@
   DCHECK(is_valid_language_mode(args.smi_at(3)));
   LanguageMode language_mode = static_cast<LanguageMode>(args.smi_at(3));
   DCHECK(args[4]->IsSmi());
   Handle<SharedFunctionInfo> outer_info(args.at<JSFunction>(2)->shared(),
                                         isolate);
   return CompileGlobalEval(isolate, args.at<String>(1), outer_info,
                            language_mode, args.smi_at(4));
 }
 }  // namespace internal
 }  // namespace v8