Make sure that on x86 we don't generate SSE2 code in the snapshot.

BUG=

Review URL: https://codereview.chromium.org/12391033

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13844 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/assembler-arm.h

@@ -74,31 +74,10 @@ class CpuFeatures : public AllStatic {
             (static_cast<uint64_t>(1) << f)) != 0;
   }
 
-  class TryForceFeatureScope BASE_EMBEDDED {
-   public:
-    explicit TryForceFeatureScope(CpuFeature f)
-        : old_supported_(CpuFeatures::supported_) {
-      if (CanForce()) {
-        CpuFeatures::supported_ |= (1u << f);
-      }
-    }
-
-    ~TryForceFeatureScope() {
-      if (CanForce()) {
-        CpuFeatures::supported_ = old_supported_;
-      }
-    }
-
-   private:
-    static bool CanForce() {
-      // It's only safe to temporarily force support of CPU features
-      // when there's only a single isolate, which is guaranteed when
-      // the serializer is enabled.
-      return Serializer::enabled();
-    }
-
-    const unsigned old_supported_;
-  };
+  static bool IsSafeForSnapshot(CpuFeature f) {
+    return (IsSupported(f) &&
+            (!Serializer::enabled() || !IsFoundByRuntimeProbingOnly(f)));
+  }
 
  private:
 #ifdef DEBUG

src/arm/builtins-arm.cc

@@ -1377,12 +1377,6 @@ void Builtins::Generate_NotifyOSR(MacroAssembler* masm) {
 
 
 void Builtins::Generate_OnStackReplacement(MacroAssembler* masm) {
-  CpuFeatures::TryForceFeatureScope scope(VFP3);
-  if (!CPU::SupportsCrankshaft()) {
-    __ Abort("Unreachable code: Cannot optimize without VFP3 support.");
-    return;
-  }
-
   // Lookup the function in the JavaScript frame and push it as an
   // argument to the on-stack replacement function.
   __ ldr(r0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));

src/assembler.cc

@@ -186,9 +186,7 @@ PredictableCodeSizeScope::~PredictableCodeSizeScope() {
 #ifdef DEBUG
 CpuFeatureScope::CpuFeatureScope(AssemblerBase* assembler, CpuFeature f)
     : assembler_(assembler) {
-  ASSERT(CpuFeatures::IsSupported(f));
-  ASSERT(!Serializer::enabled() ||
-         !CpuFeatures::IsFoundByRuntimeProbingOnly(f));
+  ASSERT(CpuFeatures::IsSafeForSnapshot(f));
   old_enabled_ = assembler_->enabled_cpu_features();
   uint64_t mask = static_cast<uint64_t>(1) << f;
   // TODO(svenpanne) This special case below doesn't belong here!

src/ia32/assembler-ia32.h

@@ -536,31 +536,10 @@ class CpuFeatures : public AllStatic {
             (static_cast<uint64_t>(1) << f)) != 0;
   }
 
-  class TryForceFeatureScope BASE_EMBEDDED {
-   public:
-    explicit TryForceFeatureScope(CpuFeature f)
-        : old_supported_(CpuFeatures::supported_) {
-      if (CanForce()) {
-        CpuFeatures::supported_ |= (static_cast<uint64_t>(1) << f);
-      }
-    }
-
-    ~TryForceFeatureScope() {
-      if (CanForce()) {
-        CpuFeatures::supported_ = old_supported_;
-      }
-    }
-
-   private:
-    static bool CanForce() {
-      // It's only safe to temporarily force support of CPU features
-      // when there's only a single isolate, which is guaranteed when
-      // the serializer is enabled.
-      return Serializer::enabled();
-    }
-
-    const uint64_t old_supported_;
-  };
+  static bool IsSafeForSnapshot(CpuFeature f) {
+    return (IsSupported(f) &&
+            (!Serializer::enabled() || !IsFoundByRuntimeProbingOnly(f)));
+  }
 
  private:
 #ifdef DEBUG

src/ia32/builtins-ia32.cc

@@ -643,6 +643,8 @@ void Builtins::Generate_NotifyLazyDeoptimized(MacroAssembler* masm) {
 
 void Builtins::Generate_NotifyOSR(MacroAssembler* masm) {
   // TODO(kasperl): Do we need to save/restore the XMM registers too?
+  // TODO(mvstanton): We should save these regs, do this in a future
+  // checkin.
 
   // For now, we are relying on the fact that Runtime::NotifyOSR
   // doesn't do any garbage collection which allows us to save/restore
@@ -1792,12 +1794,6 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
 
 
 void Builtins::Generate_OnStackReplacement(MacroAssembler* masm) {
-  CpuFeatures::TryForceFeatureScope scope(SSE2);
-  if (!CpuFeatures::IsSupported(SSE2) && FLAG_debug_code) {
-    __ Abort("Unreachable code: Cannot optimize without SSE2 support.");
-    return;
-  }
-
   // Get the loop depth of the stack guard check. This is recorded in
   // a test(eax, depth) instruction right after the call.
   Label stack_check;

src/ia32/code-stubs-ia32.cc

@@ -7516,11 +7516,9 @@ bool RecordWriteStub::IsPregenerated() {
 
 void StoreBufferOverflowStub::GenerateFixedRegStubsAheadOfTime(
     Isolate* isolate) {
-  StoreBufferOverflowStub stub1(kDontSaveFPRegs);
-  stub1.GetCode(isolate)->set_is_pregenerated(true);
-
-  CpuFeatures::TryForceFeatureScope scope(SSE2);
-  if (CpuFeatures::IsSupported(SSE2)) {
+  StoreBufferOverflowStub stub(kDontSaveFPRegs);
+  stub.GetCode(isolate)->set_is_pregenerated(true);
+  if (CpuFeatures::IsSafeForSnapshot(SSE2)) {
     StoreBufferOverflowStub stub2(kSaveFPRegs);
     stub2.GetCode(isolate)->set_is_pregenerated(true);
   }

src/ia32/code-stubs-ia32.h

@@ -64,7 +64,9 @@ class TranscendentalCacheStub: public PlatformCodeStub {
 class StoreBufferOverflowStub: public PlatformCodeStub {
  public:
   explicit StoreBufferOverflowStub(SaveFPRegsMode save_fp)
-      : save_doubles_(save_fp) { }
+      : save_doubles_(save_fp) {
+    ASSERT(CpuFeatures::IsSafeForSnapshot(SSE2) || save_fp == kDontSaveFPRegs);
+  }
 
   void Generate(MacroAssembler* masm);
 
@@ -397,6 +399,7 @@ class RecordWriteStub: public PlatformCodeStub {
         regs_(object,   // An input reg.
               address,  // An input reg.
               value) {  // One scratch reg.
+    ASSERT(CpuFeatures::IsSafeForSnapshot(SSE2) || fp_mode == kDontSaveFPRegs);
   }
 
   enum Mode {

src/ia32/lithium-codegen-ia32.cc

@@ -40,6 +40,12 @@ namespace v8 {
 namespace internal {
 
 
+static SaveFPRegsMode GetSaveFPRegsMode() {
+  // We don't need to save floating point regs when generating the snapshot
+  return CpuFeatures::IsSafeForSnapshot(SSE2) ? kSaveFPRegs : kDontSaveFPRegs;
+}
+
+
 // When invoking builtins, we need to record the safepoint in the middle of
 // the invoke instruction sequence generated by the macro assembler.
 class SafepointGenerator : public CallWrapper {
@@ -2847,7 +2853,7 @@ void LCodeGen::DoStoreContextSlot(LStoreContextSlot* instr) {
                               offset,
                               value,
                               temp,
-                              kSaveFPRegs,
+                              GetSaveFPRegsMode(),
                               EMIT_REMEMBERED_SET,
                               check_needed);
   }
@@ -4179,7 +4185,7 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
                           HeapObject::kMapOffset,
                           temp_map,
                           temp,
-                          kSaveFPRegs,
+                          GetSaveFPRegsMode(),
                           OMIT_REMEMBERED_SET,
                           OMIT_SMI_CHECK);
     }
@@ -4198,7 +4204,7 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
                           offset,
                           value,
                           temp,
-                          kSaveFPRegs,
+                          GetSaveFPRegsMode(),
                           EMIT_REMEMBERED_SET,
                           check_needed);
     }
@@ -4213,7 +4219,7 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
                           offset,
                           value,
                           object,
-                          kSaveFPRegs,
+                          GetSaveFPRegsMode(),
                           EMIT_REMEMBERED_SET,
                           check_needed);
     }
@@ -4360,7 +4366,7 @@ void LCodeGen::DoStoreKeyedFixedArray(LStoreKeyed* instr) {
     __ RecordWrite(elements,
                    key,
                    value,
-                   kSaveFPRegs,
+                   GetSaveFPRegsMode(),
                    EMIT_REMEMBERED_SET,
                    check_needed);
   }

src/isolate.cc

@@ -2156,8 +2156,10 @@ bool Isolate::Init(Deserializer* des) {
   }
 
   if (!Serializer::enabled()) {
-    // Ensure that the stub failure trampoline has been generated.
+    // Ensure that all stubs which need to be generated ahead of time, but
+    // cannot be serialized into the snapshot have been generated.
     HandleScope scope(this);
+    StoreBufferOverflowStub::GenerateFixedRegStubsAheadOfTime(this);
     CodeStub::GenerateFPStubs(this);
     StubFailureTrampolineStub::GenerateAheadOfTime(this);
   }

src/mips/assembler-mips.h

@@ -413,32 +413,6 @@ class CpuFeatures : public AllStatic {
             (static_cast<uint64_t>(1) << f)) != 0;
   }
 
-  class TryForceFeatureScope BASE_EMBEDDED {
-   public:
-    explicit TryForceFeatureScope(CpuFeature f)
-        : old_supported_(CpuFeatures::supported_) {
-      if (CanForce()) {
-        CpuFeatures::supported_ |= (1u << f);
-      }
-    }
-
-    ~TryForceFeatureScope() {
-      if (CanForce()) {
-        CpuFeatures::supported_ = old_supported_;
-      }
-    }
-
-   private:
-    static bool CanForce() {
-      // It's only safe to temporarily force support of CPU features
-      // when there's only a single isolate, which is guaranteed when
-      // the serializer is enabled.
-      return Serializer::enabled();
-    }
-
-    const unsigned old_supported_;
-  };
-
  private:
 #ifdef DEBUG
   static bool initialized_;

src/mips/builtins-mips.cc

@@ -1409,12 +1409,6 @@ void Builtins::Generate_NotifyOSR(MacroAssembler* masm) {
 
 
 void Builtins::Generate_OnStackReplacement(MacroAssembler* masm) {
-  CpuFeatures::TryForceFeatureScope scope(VFP3);
-  if (!CpuFeatures::IsSupported(FPU)) {
-    __ Abort("Unreachable code: Cannot optimize without FPU support.");
-    return;
-  }
-
   // Lookup the function in the JavaScript frame and push it as an
   // argument to the on-stack replacement function.
   __ lw(a0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));

src/x64/assembler-x64.h

@@ -474,6 +474,11 @@ class CpuFeatures : public AllStatic {
             (static_cast<uint64_t>(1) << f)) != 0;
   }
 
+  static bool IsSafeForSnapshot(CpuFeature f) {
+    return (IsSupported(f) &&
+            (!Serializer::enabled() || !IsFoundByRuntimeProbingOnly(f)));
+  }
+
  private:
   // Safe defaults include SSE2 and CMOV for X64. It is always available, if
   // anyone checks, but they shouldn't need to check.