From b1fe586e6bd553c3a9d69e53d2ffc7fbeeb4fabb Mon Sep 17 00:00:00 2001
From: "mstarzinger@chromium.org"
 <mstarzinger@chromium.org@ce2b1a6d-e550-0410-aec6-3dcde31c8c00>
Date: Mon, 18 Jun 2012 13:26:43 +0000
Subject: [PATCH] Fix optimized code caching in FastNewClosureStub.

This fixes a corner-case on ARM and MIPS where optimized code was not
shared immediately across closures when a function was used in several
global contexts at once.

R=ulan@chromium.org
TEST=cctest/test-compiler/OptimizedCodeSharing

Review URL: https://chromiumcodereview.appspot.com/10544205

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11850 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
---
 src/arm/code-stubs-arm.cc    |  1 -
 src/mips/code-stubs-mips.cc  |  1 -
 test/cctest/test-compiler.cc | 29 +++++++++++++++++++++++++++++
 3 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/src/arm/code-stubs-arm.cc b/src/arm/code-stubs-arm.cc
index 7c0db4cbbf..169a032fb0 100644
--- a/src/arm/code-stubs-arm.cc
+++ b/src/arm/code-stubs-arm.cc
@@ -158,7 +158,6 @@ void FastNewClosureStub::Generate(MacroAssembler* masm) {
   __ ldr(r5, FieldMemOperand(r1, FixedArray::kHeaderSize));
   __ cmp(r2, r5);
   __ b(eq, &install_optimized);
-  __ b(&install_unoptimized);
 
   // Iterate through the rest of map backwards.  r4 holds an index as a Smi.
   Label loop;
diff --git a/src/mips/code-stubs-mips.cc b/src/mips/code-stubs-mips.cc
index 2155b18647..7ae84fa9ff 100644
--- a/src/mips/code-stubs-mips.cc
+++ b/src/mips/code-stubs-mips.cc
@@ -159,7 +159,6 @@ void FastNewClosureStub::Generate(MacroAssembler* masm) {
   __ lw(t0, FieldMemOperand(a1, FixedArray::kHeaderSize + kPointerSize));
   __ lw(t1, FieldMemOperand(a1, FixedArray::kHeaderSize));
   __ Branch(&install_optimized, eq, a2, Operand(t1));
-  __ Branch(&install_unoptimized);
 
   // Iterate through the rest of map backwards.  t0 holds an index as a Smi.
   Label loop;
diff --git a/test/cctest/test-compiler.cc b/test/cctest/test-compiler.cc
index 9ca0b0a170..e366a06828 100644
--- a/test/cctest/test-compiler.cc
+++ b/test/cctest/test-compiler.cc
@@ -352,6 +352,35 @@ TEST(GetScriptLineNumber) {
 }
 
 
+// Test that optimized code for different closures is actually shared
+// immediately by the FastNewClosureStub when run in the same context.
+TEST(OptimizedCodeSharing) {
+  FLAG_allow_natives_syntax = true;
+  InitializeVM();
+  v8::HandleScope scope;
+  for (int i = 0; i < 10; i++) {
+    LocalContext env;
+    env->Global()->Set(v8::String::New("x"), v8::Integer::New(i));
+    CompileRun("function MakeClosure() {"
+               "  return function() { return x; };"
+               "}"
+               "var closure0 = MakeClosure();"
+               "%DebugPrint(closure0());"
+               "%OptimizeFunctionOnNextCall(closure0);"
+               "%DebugPrint(closure0());"
+               "var closure1 = MakeClosure();"
+               "var closure2 = MakeClosure();");
+    Handle<JSFunction> fun1 = v8::Utils::OpenHandle(
+        *v8::Local<v8::Function>::Cast(env->Global()->Get(v8_str("closure1"))));
+    Handle<JSFunction> fun2 = v8::Utils::OpenHandle(
+        *v8::Local<v8::Function>::Cast(env->Global()->Get(v8_str("closure2"))));
+    CHECK(fun1->IsOptimized() || !FLAG_crankshaft);
+    CHECK(fun2->IsOptimized() || !FLAG_crankshaft);
+    CHECK_EQ(fun1->code(), fun2->code());
+  }
+}
+
+
 #ifdef ENABLE_DISASSEMBLER
 static Handle<JSFunction> GetJSFunction(v8::Handle<v8::Object> obj,
                                  const char* property_name) {