Merge (7265, 7271] from bleeding_edge to experimental/gc branch....

src/x64/assembler-x64.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // All Rights Reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 // - Redistributions of source code must retain the above copyright notice,
 // this list of conditions and the following disclaimer.
 //
@@ skipping 422 matching lines @@
 
 // CpuFeatures keeps track of which features are supported by the target CPU.
 // Supported features must be enabled by a Scope before use.
 // Example:
 //   if (CpuFeatures::IsSupported(SSE3)) {
 //     CpuFeatures::Scope fscope(SSE3);
 //     // Generate SSE3 floating point code.
 //   } else {
 //     // Generate standard x87 or SSE2 floating point code.
 //   }
-class CpuFeatures : public AllStatic {
+class CpuFeatures {
  public:
   // Detect features of the target CPU. Set safe defaults if the serializer
   // is enabled (snapshots must be portable).
-  static void Probe(bool portable);
+  void Probe(bool portable);
+
   // Check whether a feature is supported by the target CPU.
-  static bool IsSupported(CpuFeature f) {
+  bool IsSupported(CpuFeature f) const {
     if (f == SSE2 && !FLAG_enable_sse2) return false;
     if (f == SSE3 && !FLAG_enable_sse3) return false;
     if (f == CMOV && !FLAG_enable_cmov) return false;
     if (f == RDTSC && !FLAG_enable_rdtsc) return false;
     if (f == SAHF && !FLAG_enable_sahf) return false;
     return (supported_ & (V8_UINT64_C(1) << f)) != 0;
   }
   // Check whether a feature is currently enabled.
-  static bool IsEnabled(CpuFeature f) {
+  bool IsEnabled(CpuFeature f) const {
     return (enabled_ & (V8_UINT64_C(1) << f)) != 0;
   }
   // Enable a specified feature within a scope.
   class Scope BASE_EMBEDDED {
 #ifdef DEBUG
    public:
-    explicit Scope(CpuFeature f) {
+    explicit Scope(CpuFeature f)
+        : cpu_features_(Isolate::Current()->cpu_features()),
+          isolate_(Isolate::Current()) {
       uint64_t mask = (V8_UINT64_C(1) << f);
-      ASSERT(CpuFeatures::IsSupported(f));
-      ASSERT(!Serializer::enabled() || (found_by_runtime_probing_ & mask) == 0);
-      old_enabled_ = CpuFeatures::enabled_;
-      CpuFeatures::enabled_ |= mask;
+      ASSERT(cpu_features_->IsSupported(f));
+      ASSERT(!Serializer::enabled() ||
+          (cpu_features_->found_by_runtime_probing_ & mask) == 0);
+      old_enabled_ = cpu_features_->enabled_;
+      cpu_features_->enabled_ |= mask;
     }
-    ~Scope() { CpuFeatures::enabled_ = old_enabled_; }
+    ~Scope() {
+      ASSERT_EQ(Isolate::Current(), isolate_);
+      cpu_features_->enabled_ = old_enabled_;
+    }
    private:
     uint64_t old_enabled_;
+    CpuFeatures* cpu_features_;
+    Isolate* isolate_;
 #else
    public:
     explicit Scope(CpuFeature f) {}
 #endif
   };
  private:
+  CpuFeatures();
+
   // Safe defaults include SSE2 and CMOV for X64. It is always available, if
   // anyone checks, but they shouldn't need to check.
+  // The required user mode extensions in X64 are (from AMD64 ABI Table A.1):
+  //   fpu, tsc, cx8, cmov, mmx, sse, sse2, fxsr, syscall
   static const uint64_t kDefaultCpuFeatures = (1 << SSE2 | 1 << CMOV);
-  static uint64_t supported_;
-  static uint64_t enabled_;
-  static uint64_t found_by_runtime_probing_;
+
+  uint64_t supported_;
+  uint64_t enabled_;
+  uint64_t found_by_runtime_probing_;
+
+  friend class Isolate;
+
+  DISALLOW_COPY_AND_ASSIGN(CpuFeatures);
 };
 
 
 class Assembler : public Malloced {
  private:
   // We check before assembling an instruction that there is sufficient
   // space to write an instruction and its relocation information.
   // The relocation writer's position must be kGap bytes above the end of
   // the generated instructions. This leaves enough space for the
   // longest possible x64 instruction, 15 bytes, and the longest possible
@@ skipping 1051 matching lines @@
   friend class CodePatcher;
   friend class EnsureSpace;
   friend class RegExpMacroAssemblerX64;
 
   // Code buffer:
   // The buffer into which code and relocation info are generated.
   byte* buffer_;
   int buffer_size_;
   // True if the assembler owns the buffer, false if buffer is external.
   bool own_buffer_;
-  // A previously allocated buffer of kMinimalBufferSize bytes, or NULL.
-  static byte* spare_buffer_;
 
   // code generation
   byte* pc_;  // the program counter; moves forward
   RelocInfoWriter reloc_info_writer;
 
   List< Handle<Code> > code_targets_;
   // push-pop elimination
   byte* last_pc_;
 
   PositionsRecorder positions_recorder_;
@@ skipping 27 matching lines @@
  private:
   Assembler* assembler_;
 #ifdef DEBUG
   int space_before_;
 #endif
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_ASSEMBLER_X64_H_