Remove custom win64 modulo code

Just use the same workaround as on win32.

Also replace fmod calls with modulo() for consistency

BUG=none
R=yangguo@chromium.org
LOG=n

Review URL: https://codereview.chromium.org/1479773002

Cr-Commit-Position: refs/heads/master@{#32322}

src/arm64/simulator-arm64.cc

@@ -2759,7 +2759,7 @@ double Simulator::FPRoundInt(double value, FPRounding round_mode) {
       // If the error is greater than 0.5, or is equal to 0.5 and the integer
       // result is odd, round up.
       } else if ((error > 0.5) ||
-          ((error == 0.5) && (fmod(int_result, 2) != 0))) {
+                 ((error == 0.5) && (modulo(int_result, 2) != 0))) {
         int_result++;
       }
       break;

src/codegen.cc

@@ -20,24 +20,7 @@ namespace v8 {
 namespace internal {
 
 
-#if defined(_WIN64)
-typedef double (*ModuloFunction)(double, double);
-static ModuloFunction modulo_function = NULL;
-// Defined in codegen-x64.cc.
-ModuloFunction CreateModuloFunction();
-
-void init_modulo_function() {
-  modulo_function = CreateModuloFunction();
-}
-
-
-double modulo(double x, double y) {
-  // Note: here we rely on dependent reads being ordered. This is true
-  // on all architectures we currently support.
-  return (*modulo_function)(x, y);
-}
-#elif defined(_WIN32)
-
+#if defined(V8_OS_WIN)
 double modulo(double x, double y) {
   // Workaround MS fmod bugs. ECMA-262 says:
   // dividend is finite and divisor is an infinity => result equals dividend
@@ -61,7 +44,7 @@ double modulo(double x, double y) {
   return std::fmod(x, y);
 #endif
 }
-#endif  // defined(_WIN64)
+#endif  // defined(V8_OS_WIN)
 
 
 #define UNARY_MATH_FUNCTION(name, generator)                             \

src/codegen.h

@@ -100,9 +100,6 @@ double modulo(double x, double y);
 // Custom implementation of math functions.
 double fast_exp(double input, Isolate* isolate);
 double fast_sqrt(double input, Isolate* isolate);
-#ifdef _WIN64
-void init_modulo_function();
-#endif
 void lazily_initialize_fast_exp(Isolate* isolate);
 void lazily_initialize_fast_sqrt(Isolate* isolate);
 

src/conversions.cc

@@ -10,6 +10,7 @@
 
 #include "src/assert-scope.h"
 #include "src/char-predicates-inl.h"
+#include "src/codegen.h"
 #include "src/conversions-inl.h"
 #include "src/dtoa.h"
 #include "src/factory.h"
@@ -440,7 +441,7 @@ char* DoubleToRadixCString(double value, int radix) {
   // at least one digit.
   int integer_pos = kBufferSize - 2;
   do {
-    double remainder = std::fmod(integer_part, radix);
+    double remainder = modulo(integer_part, radix);
     integer_buffer[integer_pos--] = chars[static_cast<int>(remainder)];
     integer_part -= remainder;
     integer_part /= radix;

src/v8.cc

@@ -80,9 +80,6 @@ void V8::InitializeOncePerProcessImpl() {
   Sampler::SetUp();
   CpuFeatures::Probe(false);
   init_memcopy_functions();
-#ifdef _WIN64
-  init_modulo_function();
-#endif
   ElementsAccessor::InitializeOncePerProcess();
   LOperand::SetUpCaches();
   SetUpJSCallerSavedCodeData();

src/x64/codegen-x64.cc

@@ -87,97 +87,6 @@ UnaryMathFunctionWithIsolate CreateSqrtFunction(Isolate* isolate) {
   return FUNCTION_CAST<UnaryMathFunctionWithIsolate>(buffer);
 }
 
-
-#ifdef _WIN64
-typedef double (*ModuloFunction)(double, double);
-// Define custom fmod implementation.
-ModuloFunction CreateModuloFunction() {
-  size_t actual_size;
-  byte* buffer = static_cast<byte*>(
-      base::OS::Allocate(Assembler::kMinimalBufferSize, &actual_size, true));
-  CHECK(buffer);
-  MacroAssembler masm(NULL, buffer, static_cast<int>(actual_size),
-                      CodeObjectRequired::kNo);
-  // Generated code is put into a fixed, unmovable, buffer, and not into
-  // the V8 heap. We can't, and don't, refer to any relocatable addresses
-  // (e.g. the JavaScript nan-object).
-
-  // Windows 64 ABI passes double arguments in xmm0, xmm1 and
-  // returns result in xmm0.
-  // Argument backing space is allocated on the stack above
-  // the return address.
-
-  // Compute x mod y.
-  // Load y and x (use argument backing store as temporary storage).
-  __ Movsd(Operand(rsp, kRegisterSize * 2), xmm1);
-  __ Movsd(Operand(rsp, kRegisterSize), xmm0);
-  __ fld_d(Operand(rsp, kRegisterSize * 2));
-  __ fld_d(Operand(rsp, kRegisterSize));
-
-  // Clear exception flags before operation.
-  {
-    Label no_exceptions;
-    __ fwait();
-    __ fnstsw_ax();
-    // Clear if Illegal Operand or Zero Division exceptions are set.
-    __ testb(rax, Immediate(5));
-    __ j(zero, &no_exceptions);
-    __ fnclex();
-    __ bind(&no_exceptions);
-  }
-
-  // Compute st(0) % st(1)
-  {
-    Label partial_remainder_loop;
-    __ bind(&partial_remainder_loop);
-    __ fprem();
-    __ fwait();
-    __ fnstsw_ax();
-    __ testl(rax, Immediate(0x400 /* C2 */));
-    // If C2 is set, computation only has partial result. Loop to
-    // continue computation.
-    __ j(not_zero, &partial_remainder_loop);
-  }
-
-  Label valid_result;
-  Label return_result;
-  // If Invalid Operand or Zero Division exceptions are set,
-  // return NaN.
-  __ testb(rax, Immediate(5));
-  __ j(zero, &valid_result);
-  __ fstp(0);  // Drop result in st(0).
-  int64_t kNaNValue = V8_INT64_C(0x7ff8000000000000);
-  __ movq(rcx, kNaNValue);
-  __ movq(Operand(rsp, kRegisterSize), rcx);
-  __ Movsd(xmm0, Operand(rsp, kRegisterSize));
-  __ jmp(&return_result);
-
-  // If result is valid, return that.
-  __ bind(&valid_result);
-  __ fstp_d(Operand(rsp, kRegisterSize));
-  __ Movsd(xmm0, Operand(rsp, kRegisterSize));
-
-  // Clean up FPU stack and exceptions and return xmm0
-  __ bind(&return_result);
-  __ fstp(0);  // Unload y.
-
-  Label clear_exceptions;
-  __ testb(rax, Immediate(0x3f /* Any Exception*/));
-  __ j(not_zero, &clear_exceptions);
-  __ ret(0);
-  __ bind(&clear_exceptions);
-  __ fnclex();
-  __ ret(0);
-
-  CodeDesc desc;
-  masm.GetCode(&desc);
-  base::OS::ProtectCode(buffer, actual_size);
-  // Call the function from C++ through this pointer.
-  return FUNCTION_CAST<ModuloFunction>(buffer);
-}
-
-#endif
-
 #undef __
 
 // -------------------------------------------------------------------------