Simplified CPU/CpuFeatures a bit.

This is a necessary intermediate step to disentangle the startup.

In the long run CPU and CpuFeatures should probably be merged,
and Serializer::enabled usage should be radically reduced, but
we're not there yet.

BUG=359977
LOG=y
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/258993002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@21001 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/assembler-arm.cc

@@ -48,7 +48,6 @@ namespace internal {
 #ifdef DEBUG
 bool CpuFeatures::initialized_ = false;
 #endif
-bool CpuFeatures::hint_creating_snapshot_ = false;
 unsigned CpuFeatures::supported_ = 0;
 unsigned CpuFeatures::found_by_runtime_probing_only_ = 0;
 unsigned CpuFeatures::cross_compile_ = 0;
@@ -101,22 +100,6 @@ const char* DwVfpRegister::AllocationIndexToString(int index) {
 }
 
 
-void CpuFeatures::SetHintCreatingSnapshot() {
-  hint_creating_snapshot_ = true;
-}
-
-
-void CpuFeatures::ProbeWithoutIsolate() {
-  Probe(hint_creating_snapshot_);
-}
-
-
-void CpuFeatures::Probe() {
-  // The Serializer can only be queried after isolate initialization.
-  Probe(Serializer::enabled());
-}
-
-
 void CpuFeatures::Probe(bool serializer_enabled) {
   uint64_t standard_features = static_cast<unsigned>(
       OS::CpuFeaturesImpliedByPlatform()) | CpuFeaturesImpliedByCompiler();
@@ -133,8 +116,6 @@ void CpuFeatures::Probe(bool serializer_enabled) {
 
   if (serializer_enabled) {
     // No probing for features if we might serialize (generate snapshot).
-    printf("   ");
-    PrintFeatures();
     return;
   }
 

src/arm/assembler-arm.h

@@ -56,12 +56,7 @@ class CpuFeatures : public AllStatic {
  public:
   // Detect features of the target CPU. Set safe defaults if the serializer
   // is enabled (snapshots must be portable).
-  static void Probe();
-
-  // A special case for printing target and features, which we want to do
-  // before initializing the isolate
-  static void SetHintCreatingSnapshot();
-  static void ProbeWithoutIsolate();
+  static void Probe(bool serializer_enabled);
 
   // Display target use when compiling.
   static void PrintTarget();
@@ -98,10 +93,9 @@ class CpuFeatures : public AllStatic {
            (cross_compile_ & mask) == mask;
   }
 
- private:
-  static void Probe(bool serializer_enabled);
-  static bool hint_creating_snapshot_;
+  static bool SupportsCrankshaft() { return CpuFeatures::IsSupported(VFP3); }
 
+ private:
   static bool Check(CpuFeature f, unsigned set) {
     return (set & flag2set(f)) != 0;
   }

src/arm/cpu-arm.cc

@@ -46,16 +46,6 @@
 namespace v8 {
 namespace internal {
 
-void CPU::SetUp() {
-  CpuFeatures::Probe();
-}
-
-
-bool CPU::SupportsCrankshaft() {
-  return CpuFeatures::IsSupported(VFP3);
-}
-
-
 void CPU::FlushICache(void* start, size_t size) {
   // Nothing to do flushing no instructions.
   if (size == 0) {

src/arm64/cpu-arm64.cc

@@ -49,16 +49,6 @@ unsigned CpuFeatures::dcache_line_size_ = 1;
 unsigned CpuFeatures::icache_line_size_ = 1;
 
 
-void CPU::SetUp() {
-  CpuFeatures::Probe();
-}
-
-
-bool CPU::SupportsCrankshaft() {
-  return true;
-}
-
-
 void CPU::FlushICache(void* address, size_t length) {
   if (length == 0) {
     return;
@@ -139,7 +129,7 @@ void CPU::FlushICache(void* address, size_t length) {
 }
 
 
-void CpuFeatures::Probe() {
+void CpuFeatures::Probe(bool serializer_enabled) {
   // Compute I and D cache line size. The cache type register holds
   // information about the caches.
   uint32_t cache_type_register = GetCacheType();

src/arm64/cpu-arm64.h

@@ -42,7 +42,7 @@ class CpuFeatures : public AllStatic {
  public:
   // Detect features of the target CPU. Set safe defaults if the serializer
   // is enabled (snapshots must be portable).
-  static void Probe();
+  static void Probe(bool serializer_enabled);
 
   // Check whether a feature is supported by the target CPU.
   static bool IsSupported(CpuFeature f) {
@@ -81,6 +81,8 @@ class CpuFeatures : public AllStatic {
     return true;
   }
 
+  static bool SupportsCrankshaft() { return true; }
+
  private:
   // Return the content of the cache type register.
   static uint32_t GetCacheType();

src/cpu.h

@@ -102,11 +102,6 @@ class CPU V8_FINAL BASE_EMBEDDED {
   // Returns the number of processors online.
   static int NumberOfProcessorsOnline();
 
-  // Initializes the cpu architecture support. Called once at VM startup.
-  static void SetUp();
-
-  static bool SupportsCrankshaft();
-
   // Flush instruction cache.
   static void FlushICache(void* start, size_t size);
 

src/flags.cc

@@ -360,10 +360,15 @@ static Flag* FindFlag(const char* name) {
 }
 
 
+bool FlagList::serializer_enabled_ = false;
+
+
 // static
 int FlagList::SetFlagsFromCommandLine(int* argc,
                                       char** argv,
-                                      bool remove_flags) {
+                                      bool remove_flags,
+                                      bool serializer_enabled) {
+  serializer_enabled_ = serializer_enabled;
   int return_code = 0;
   // parse arguments
   for (int i = 1; i < *argc;) {
@@ -545,7 +550,7 @@ void FlagList::ResetAllFlags() {
 void FlagList::PrintHelp() {
 #if V8_TARGET_ARCH_ARM
   CpuFeatures::PrintTarget();
-  CpuFeatures::ProbeWithoutIsolate();
+  CpuFeatures::Probe(serializer_enabled_);
   CpuFeatures::PrintFeatures();
 #endif  // V8_TARGET_ARCH_ARM
 

src/flags.h

@@ -63,7 +63,10 @@ class FlagList {
   //   --flag=value  (non-bool flags only, no spaces around '=')
   //   --flag value  (non-bool flags only)
   //   --            (equivalent to --js_arguments, captures all remaining args)
-  static int SetFlagsFromCommandLine(int* argc, char** argv, bool remove_flags);
+  static int SetFlagsFromCommandLine(int* argc,
+                                     char** argv,
+                                     bool remove_flags,
+                                     bool serializer_enabled = false);
 
   // Set the flag values by parsing the string str. Splits string into argc
   // substrings argv[], each of which consisting of non-white-space chars,
@@ -78,6 +81,10 @@ class FlagList {
 
   // Set flags as consequence of being implied by another flag.
   static void EnforceFlagImplications();
+
+ private:
+  // TODO(svenpanne) Remove this when Serializer/startup has been refactored.
+  static bool serializer_enabled_;
 };
 
 } }  // namespace v8::internal

src/ia32/assembler-ia32.cc

@@ -89,13 +89,13 @@ const char* IntelDoubleRegister::AllocationIndexToString(int index) {
 }
 
 
-void CpuFeatures::Probe() {
+void CpuFeatures::Probe(bool serializer_enabled) {
   ASSERT(!initialized_);
   ASSERT(supported_ == 0);
 #ifdef DEBUG
   initialized_ = true;
 #endif
-  if (Serializer::enabled()) {
+  if (serializer_enabled) {
     supported_ |= OS::CpuFeaturesImpliedByPlatform();
     return;  // No features if we might serialize.
   }

src/ia32/assembler-ia32.h

@@ -530,7 +530,7 @@ class CpuFeatures : public AllStatic {
  public:
   // Detect features of the target CPU. Set safe defaults if the serializer
   // is enabled (snapshots must be portable).
-  static void Probe();
+  static void Probe(bool serializer_enabled);
 
   // Check whether a feature is supported by the target CPU.
   static bool IsSupported(CpuFeature f) {
@@ -564,6 +564,8 @@ class CpuFeatures : public AllStatic {
            (cross_compile_ & mask) == mask;
   }
 
+  static bool SupportsCrankshaft() { return IsSupported(SSE2); }
+
  private:
   static bool Check(CpuFeature f, uint64_t set) {
     return (set & flag2set(f)) != 0;

src/ia32/cpu-ia32.cc

@@ -41,16 +41,6 @@
 namespace v8 {
 namespace internal {
 
-void CPU::SetUp() {
-  CpuFeatures::Probe();
-}
-
-
-bool CPU::SupportsCrankshaft() {
-  return CpuFeatures::IsSupported(SSE2);
-}
-
-
 void CPU::FlushICache(void* start, size_t size) {
   // No need to flush the instruction cache on Intel. On Intel instruction
   // cache flushing is only necessary when multiple cores running the same

src/isolate.cc

@@ -1808,7 +1808,7 @@ bool Isolate::Init(Deserializer* des) {
 
   use_crankshaft_ = FLAG_crankshaft
       && !Serializer::enabled()
-      && CPU::SupportsCrankshaft();
+      && CpuFeatures::SupportsCrankshaft();
 
   if (function_entry_hook() != NULL) {
     // When function entry hooking is in effect, we have to create the code

src/mips/assembler-mips.cc

@@ -46,7 +46,6 @@ namespace internal {
 #ifdef DEBUG
 bool CpuFeatures::initialized_ = false;
 #endif
-bool CpuFeatures::hint_creating_snapshot_ = false;
 unsigned CpuFeatures::supported_ = 0;
 unsigned CpuFeatures::found_by_runtime_probing_only_ = 0;
 unsigned CpuFeatures::cross_compile_ = 0;
@@ -103,22 +102,6 @@ const char* DoubleRegister::AllocationIndexToString(int index) {
 }
 
 
-void CpuFeatures::SetHintCreatingSnapshot() {
-  hint_creating_snapshot_ = true;
-}
-
-
-void CpuFeatures::ProbeWithoutIsolate() {
-  Probe(hint_creating_snapshot_);
-}
-
-
-void CpuFeatures::Probe() {
-  // The Serializer can only be queried after isolate initialization.
-  Probe(Serializer::enabled());
-}
-
-
 void CpuFeatures::Probe(bool serializer_enabled) {
   unsigned standard_features = (OS::CpuFeaturesImpliedByPlatform() |
                                 CpuFeaturesImpliedByCompiler());

src/mips/assembler-mips.h

@@ -425,12 +425,10 @@ class CpuFeatures : public AllStatic {
  public:
   // Detect features of the target CPU. Set safe defaults if the serializer
   // is enabled (snapshots must be portable).
-  static void Probe();
+  static void Probe(bool serializer_enabled);
 
   // A special case for printing target and features, which we want to do
   // before initializing the isolate
-  static void SetHintCreatingSnapshot();
-  static void ProbeWithoutIsolate();
 
   // Check whether a feature is supported by the target CPU.
   static bool IsSupported(CpuFeature f) {
@@ -459,10 +457,9 @@ class CpuFeatures : public AllStatic {
            (cross_compile_ & mask) == mask;
   }
 
- private:
-  static void Probe(bool serializer_enabled);
-  static bool hint_creating_snapshot_;
+  static bool SupportsCrankshaft() { return CpuFeatures::IsSupported(FPU); }
 
+ private:
   static bool Check(CpuFeature f, unsigned set) {
     return (set & flag2set(f)) != 0;
   }

src/mips/cpu-mips.cc

@@ -47,16 +47,6 @@ namespace v8 {
 namespace internal {
 
 
-void CPU::SetUp() {
-  CpuFeatures::Probe();
-}
-
-
-bool CPU::SupportsCrankshaft() {
-  return CpuFeatures::IsSupported(FPU);
-}
-
-
 void CPU::FlushICache(void* start, size_t size) {
   // Nothing to do, flushing no instructions.
   if (size == 0) {

src/mksnapshot.cc

@@ -301,15 +301,9 @@ int main(int argc, char** argv) {
   // By default, log code create information in the snapshot.
   i::FLAG_log_code = true;
 
-#if V8_TARGET_ARCH_ARM
-  // Printing flags on ARM requires knowing if we intend to enable
-  // the serializer or not.
-  v8::internal::CpuFeatures::SetHintCreatingSnapshot();
-#endif
-
   // Print the usage if an error occurs when parsing the command line
   // flags or if the help flag is set.
-  int result = i::FlagList::SetFlagsFromCommandLine(&argc, argv, true);
+  int result = i::FlagList::SetFlagsFromCommandLine(&argc, argv, true, true);
   if (result > 0 || argc != 2 || i::FLAG_help) {
     ::printf("Usage: %s [flag] ... outfile\n", argv[0]);
     i::FlagList::PrintHelp();

src/v8.cc

@@ -144,7 +144,7 @@ void V8::InitializeOncePerProcessImpl() {
   platform_ = new DefaultPlatform;
 #endif
   Sampler::SetUp();
-  CPU::SetUp();
+  CpuFeatures::Probe(Serializer::enabled());
   OS::PostSetUp();
   ElementsAccessor::InitializeOncePerProcess();
   LOperand::SetUpCaches();

src/x64/assembler-x64.cc

@@ -52,13 +52,13 @@ ExternalReference ExternalReference::cpu_features() {
 }
 
 
-void CpuFeatures::Probe() {
+void CpuFeatures::Probe(bool serializer_enabled) {
   ASSERT(supported_ == CpuFeatures::kDefaultCpuFeatures);
 #ifdef DEBUG
   initialized_ = true;
 #endif
   supported_ = kDefaultCpuFeatures;
-  if (Serializer::enabled()) {
+  if (serializer_enabled) {
     supported_ |= OS::CpuFeaturesImpliedByPlatform();
     return;  // No features if we might serialize.
   }

src/x64/assembler-x64.h

@@ -450,7 +450,7 @@ class CpuFeatures : public AllStatic {
  public:
   // Detect features of the target CPU. Set safe defaults if the serializer
   // is enabled (snapshots must be portable).
-  static void Probe();
+  static void Probe(bool serializer_enabled);
 
   // Check whether a feature is supported by the target CPU.
   static bool IsSupported(CpuFeature f) {
@@ -484,6 +484,8 @@ class CpuFeatures : public AllStatic {
            (cross_compile_ & mask) == mask;
   }
 
+  static bool SupportsCrankshaft() { return true; }
+
  private:
   static bool Check(CpuFeature f, uint64_t set) {
     return (set & flag2set(f)) != 0;

src/x64/cpu-x64.cc

@@ -41,16 +41,6 @@
 namespace v8 {
 namespace internal {
 
-void CPU::SetUp() {
-  CpuFeatures::Probe();
-}
-
-
-bool CPU::SupportsCrankshaft() {
-  return true;  // Yay!
-}
-
-
 void CPU::FlushICache(void* start, size_t size) {
   // No need to flush the instruction cache on Intel. On Intel instruction
   // cache flushing is only necessary when multiple cores running the same