Refactor and cleanup VirtualMemory.

src/x64/codegen-x64.cc

Index: src/x64/codegen-x64.cc
diff --git a/src/x64/codegen-x64.cc b/src/x64/codegen-x64.cc
index 24773c2595d1303aac57cacd10cad243a868e9e0..9d4421eaf31cf791137dee0639460cb9b29ced0b 100644
--- a/src/x64/codegen-x64.cc
+++ b/src/x64/codegen-x64.cc
@@ -58,9 +58,8 @@ void StubRuntimeCallHelper::AfterCall(MacroAssembler* masm) const {
 UnaryMathFunction CreateTranscendentalFunction(TranscendentalCache::Type type) {
   size_t actual_size;
   // Allocate buffer in executable space.
-  byte* buffer = static_cast<byte*>(OS::Allocate(1 * KB,
-                                                 &actual_size,
-                                                 true));
+  byte* buffer = static_cast<byte*>(VirtualMemory::AllocateRegion(
+          1 * KB, &actual_size, VirtualMemory::EXECUTABLE));
   if (buffer == NULL) {
     // Fallback to library function if function cannot be created.
     switch (type) {
@@ -94,7 +93,9 @@ UnaryMathFunction CreateTranscendentalFunction(TranscendentalCache::Type type) {
   ASSERT(!RelocInfo::RequiresRelocation(desc));
 
   CPU::FlushICache(buffer, actual_size);
-  OS::ProtectCode(buffer, actual_size);
+  bool result = VirtualMemory::WriteProtectRegion(buffer, actual_size);
+  ASSERT(result);
+  USE(result);
   return FUNCTION_CAST<UnaryMathFunction>(buffer);
 }
 
@@ -102,7 +103,8 @@ UnaryMathFunction CreateTranscendentalFunction(TranscendentalCache::Type type) {
 UnaryMathFunction CreateExpFunction() {
   if (!FLAG_fast_math) return &exp;
   size_t actual_size;
-  byte* buffer = static_cast<byte*>(OS::Allocate(1 * KB, &actual_size, true));
+  byte* buffer = static_cast<byte*>(VirtualMemory::AllocateRegion(
+          1 * KB, &actual_size, VirtualMemory::EXECUTABLE));
   if (buffer == NULL) return &exp;
   ExternalReference::InitializeMathExpData();
 
@@ -125,7 +127,9 @@ UnaryMathFunction CreateExpFunction() {
   ASSERT(!RelocInfo::RequiresRelocation(desc));
 
   CPU::FlushICache(buffer, actual_size);
-  OS::ProtectCode(buffer, actual_size);
+  bool ok = VirtualMemory::WriteProtectRegion(buffer, actual_size);
+  ASSERT(ok);
+  USE(ok);
   return FUNCTION_CAST<UnaryMathFunction>(buffer);
 }
 
@@ -133,9 +137,8 @@ UnaryMathFunction CreateExpFunction() {
 UnaryMathFunction CreateSqrtFunction() {
   size_t actual_size;
   // Allocate buffer in executable space.
-  byte* buffer = static_cast<byte*>(OS::Allocate(1 * KB,
-                                                 &actual_size,
-                                                 true));
+  byte* buffer = static_cast<byte*>(VirtualMemory::AllocateRegion(
+          1 * KB, &actual_size, VirtualMemory::EXECUTABLE));
   if (buffer == NULL) return &sqrt;
 
   MacroAssembler masm(NULL, buffer, static_cast<int>(actual_size));
@@ -149,7 +152,9 @@ UnaryMathFunction CreateSqrtFunction() {
   ASSERT(!RelocInfo::RequiresRelocation(desc));
 
   CPU::FlushICache(buffer, actual_size);
-  OS::ProtectCode(buffer, actual_size);
+  bool result = VirtualMemory::WriteProtectRegion(buffer, actual_size);
+  ASSERT(result);
+  USE(result);
   return FUNCTION_CAST<UnaryMathFunction>(buffer);
 }
 
@@ -237,7 +242,9 @@ ModuloFunction CreateModuloFunction() {
 
   CodeDesc desc;
   masm.GetCode(&desc);
-  OS::ProtectCode(buffer, actual_size);
+  bool result = VirtualMemory::WriteProtectRegion(buffer, actual_size);
+  ASSERT(result);
+  USE(result);
   // Call the function from C++ through this pointer.
   return FUNCTION_CAST<ModuloFunction>(buffer);
 }