Ensure consistency of Math.sqrt on Intel platforms.

BUG=
TEST=regress-sqrt.js

Review URL: https://chromiumcodereview.appspot.com/9690010

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11012 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
yangguo@chromium.org 2012-03-12 14:56:04 +00:00
parent 12c09fdfe4
commit 7659beafb1
10 changed files with 161 additions and 50 deletions

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@ -37,8 +37,7 @@ namespace internal {
#define __ ACCESS_MASM(masm)
TranscendentalFunction CreateTranscendentalFunction(
TranscendentalCache::Type type) {
UnaryMathFunction CreateTranscendentalFunction(TranscendentalCache::Type type) {
switch (type) {
case TranscendentalCache::SIN: return &sin;
case TranscendentalCache::COS: return &cos;
@ -50,6 +49,10 @@ TranscendentalFunction CreateTranscendentalFunction(
}
UnaryMathFunction CreateSqrtFunction() {
return &sqrt;
}
// -------------------------------------------------------------------------
// Platform-specific RuntimeCallHelper functions.

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@ -87,10 +87,10 @@ namespace internal {
// Results of the library implementation of transcendental functions may differ
// from the one we use in our generated code. Therefore we use the same
// generated code both in runtime and compiled code.
typedef double (*TranscendentalFunction)(double x);
typedef double (*UnaryMathFunction)(double x);
TranscendentalFunction CreateTranscendentalFunction(
TranscendentalCache::Type type);
UnaryMathFunction CreateTranscendentalFunction(TranscendentalCache::Type type);
UnaryMathFunction CreateSqrtFunction();
class ElementsTransitionGenerator : public AllStatic {

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@ -57,8 +57,7 @@ void StubRuntimeCallHelper::AfterCall(MacroAssembler* masm) const {
#define __ masm.
TranscendentalFunction CreateTranscendentalFunction(
TranscendentalCache::Type type) {
UnaryMathFunction CreateTranscendentalFunction(TranscendentalCache::Type type) {
size_t actual_size;
// Allocate buffer in executable space.
byte* buffer = static_cast<byte*>(OS::Allocate(1 * KB,
@ -99,7 +98,40 @@ TranscendentalFunction CreateTranscendentalFunction(
CPU::FlushICache(buffer, actual_size);
OS::ProtectCode(buffer, actual_size);
return FUNCTION_CAST<TranscendentalFunction>(buffer);
return FUNCTION_CAST<UnaryMathFunction>(buffer);
}
UnaryMathFunction CreateSqrtFunction() {
size_t actual_size;
// Allocate buffer in executable space.
byte* buffer = static_cast<byte*>(OS::Allocate(1 * KB,
&actual_size,
true));
// If SSE2 is not available, we can use libc's implementation to ensure
// consistency since code by fullcodegen's calls into runtime in that case.
if (buffer == NULL || !CpuFeatures::IsSupported(SSE2)) return &sqrt;
MacroAssembler masm(NULL, buffer, static_cast<int>(actual_size));
// esp[1 * kPointerSize]: raw double input
// esp[0 * kPointerSize]: return address
// Move double input into registers.
{
CpuFeatures::Scope use_sse2(SSE2);
__ movdbl(xmm0, Operand(esp, 1 * kPointerSize));
__ sqrtsd(xmm0, xmm0);
__ movdbl(Operand(esp, 1 * kPointerSize), xmm0);
// Load result into floating point register as return value.
__ fld_d(Operand(esp, 1 * kPointerSize));
__ Ret();
}
CodeDesc desc;
masm.GetCode(&desc);
ASSERT(desc.reloc_size == 0);
CPU::FlushICache(buffer, actual_size);
OS::ProtectCode(buffer, actual_size);
return FUNCTION_CAST<UnaryMathFunction>(buffer);
}

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@ -37,8 +37,7 @@ namespace internal {
#define __ ACCESS_MASM(masm)
TranscendentalFunction CreateTranscendentalFunction(
TranscendentalCache::Type type) {
UnaryMathFunction CreateTranscendentalFunction(TranscendentalCache::Type type) {
switch (type) {
case TranscendentalCache::SIN: return &sin;
case TranscendentalCache::COS: return &cos;
@ -50,6 +49,10 @@ TranscendentalFunction CreateTranscendentalFunction(
}
UnaryMathFunction CreateSqrtFunction() {
return &sqrt;
}
// -------------------------------------------------------------------------
// Platform-specific RuntimeCallHelper functions.

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@ -127,27 +127,27 @@ double modulo(double x, double y) {
}
static Mutex* transcendental_function_mutex = OS::CreateMutex();
static Mutex* math_function_mutex = OS::CreateMutex();
#define TRANSCENDENTAL_FUNCTION(name, type) \
static TranscendentalFunction fast_##name##_function = NULL; \
#define UNARY_MATH_FUNCTION(name, generator) \
static UnaryMathFunction fast_##name##_function = NULL; \
double fast_##name(double x) { \
if (fast_##name##_function == NULL) { \
ScopedLock lock(transcendental_function_mutex); \
TranscendentalFunction temp = \
CreateTranscendentalFunction(type); \
ScopedLock lock(math_function_mutex); \
UnaryMathFunction temp = generator; \
MemoryBarrier(); \
fast_##name##_function = temp; \
} \
return (*fast_##name##_function)(x); \
}
TRANSCENDENTAL_FUNCTION(sin, TranscendentalCache::SIN)
TRANSCENDENTAL_FUNCTION(cos, TranscendentalCache::COS)
TRANSCENDENTAL_FUNCTION(tan, TranscendentalCache::TAN)
TRANSCENDENTAL_FUNCTION(log, TranscendentalCache::LOG)
UNARY_MATH_FUNCTION(sin, CreateTranscendentalFunction(TranscendentalCache::SIN))
UNARY_MATH_FUNCTION(cos, CreateTranscendentalFunction(TranscendentalCache::COS))
UNARY_MATH_FUNCTION(tan, CreateTranscendentalFunction(TranscendentalCache::TAN))
UNARY_MATH_FUNCTION(log, CreateTranscendentalFunction(TranscendentalCache::LOG))
UNARY_MATH_FUNCTION(sqrt, CreateSqrtFunction())
#undef TRANSCENDENTAL_FUNCTION
#undef MATH_FUNCTION
double OS::nan_value() {

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@ -208,27 +208,27 @@ double modulo(double x, double y) {
#endif // _WIN64
static Mutex* transcendental_function_mutex = OS::CreateMutex();
static Mutex* math_function_mutex = OS::CreateMutex();
#define TRANSCENDENTAL_FUNCTION(name, type) \
static TranscendentalFunction fast_##name##_function = NULL; \
#define UNARY_MATH_FUNCTION(name, generator) \
static UnaryMathFunction fast_##name##_function = NULL; \
double fast_##name(double x) { \
if (fast_##name##_function == NULL) { \
ScopedLock lock(transcendental_function_mutex); \
TranscendentalFunction temp = \
CreateTranscendentalFunction(type); \
ScopedLock lock(math_function_mutex); \
UnaryMathFunction temp = generator; \
MemoryBarrier(); \
fast_##name##_function = temp; \
} \
return (*fast_##name##_function)(x); \
}
TRANSCENDENTAL_FUNCTION(sin, TranscendentalCache::SIN)
TRANSCENDENTAL_FUNCTION(cos, TranscendentalCache::COS)
TRANSCENDENTAL_FUNCTION(tan, TranscendentalCache::TAN)
TRANSCENDENTAL_FUNCTION(log, TranscendentalCache::LOG)
UNARY_MATH_FUNCTION(sin, CreateTranscendentalFunction(TranscendentalCache::SIN))
UNARY_MATH_FUNCTION(cos, CreateTranscendentalFunction(TranscendentalCache::COS))
UNARY_MATH_FUNCTION(tan, CreateTranscendentalFunction(TranscendentalCache::TAN))
UNARY_MATH_FUNCTION(log, CreateTranscendentalFunction(TranscendentalCache::LOG))
UNARY_MATH_FUNCTION(sqrt, CreateSqrtFunction())
#undef TRANSCENDENTAL_FUNCTION
#undef MATH_FUNCTION
// ----------------------------------------------------------------------------

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@ -102,6 +102,7 @@ double fast_sin(double input);
double fast_cos(double input);
double fast_tan(double input);
double fast_log(double input);
double fast_sqrt(double input);
// Forward declarations.
class Socket;

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@ -7441,9 +7441,11 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_Math_pow) {
if (y == y_int) {
result = power_double_int(x, y_int); // Returns 1 if exponent is 0.
} else if (y == 0.5) {
result = (isinf(x)) ? V8_INFINITY : sqrt(x + 0.0); // Convert -0 to +0.
result = (isinf(x)) ? V8_INFINITY
: fast_sqrt(x + 0.0); // Convert -0 to +0.
} else if (y == -0.5) {
result = (isinf(x)) ? 0 : 1.0 / sqrt(x + 0.0); // Convert -0 to +0.
result = (isinf(x)) ? 0
: 1.0 / fast_sqrt(x + 0.0); // Convert -0 to +0.
} else {
result = power_double_double(x, y);
}
@ -7529,7 +7531,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_Math_sqrt) {
isolate->counters()->math_sqrt()->Increment();
CONVERT_DOUBLE_ARG_CHECKED(x, 0);
return isolate->heap()->AllocateHeapNumber(sqrt(x));
return isolate->heap()->AllocateHeapNumber(fast_sqrt(x));
}

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@ -55,8 +55,7 @@ void StubRuntimeCallHelper::AfterCall(MacroAssembler* masm) const {
#define __ masm.
TranscendentalFunction CreateTranscendentalFunction(
TranscendentalCache::Type type) {
UnaryMathFunction CreateTranscendentalFunction(TranscendentalCache::Type type) {
size_t actual_size;
// Allocate buffer in executable space.
byte* buffer = static_cast<byte*>(OS::Allocate(1 * KB,
@ -96,7 +95,31 @@ TranscendentalFunction CreateTranscendentalFunction(
CPU::FlushICache(buffer, actual_size);
OS::ProtectCode(buffer, actual_size);
return FUNCTION_CAST<TranscendentalFunction>(buffer);
return FUNCTION_CAST<UnaryMathFunction>(buffer);
}
UnaryMathFunction CreateSqrtFunction() {
size_t actual_size;
// Allocate buffer in executable space.
byte* buffer = static_cast<byte*>(OS::Allocate(1 * KB,
&actual_size,
true));
if (buffer == NULL) return &sqrt;
MacroAssembler masm(NULL, buffer, static_cast<int>(actual_size));
// xmm0: raw double input.
// Move double input into registers.
__ sqrtsd(xmm0, xmm0);
__ Ret();
CodeDesc desc;
masm.GetCode(&desc);
ASSERT(desc.reloc_size == 0);
CPU::FlushICache(buffer, actual_size);
OS::ProtectCode(buffer, actual_size);
return FUNCTION_CAST<UnaryMathFunction>(buffer);
}

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@ -0,0 +1,47 @@
// Copyright 2012 the V8 project authors. 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.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Flags: --allow-natives-syntax
// Check that Math.sqrt returns the same value regardless of being
// optimized or not.
function f(x) {
return Math.sqrt(x);
}
var x = 7.0506280066499245e-233;
var a = f(x);
f(0.1);
f(0.2);
%OptimizeFunctionOnNextCall(f);
var b = f(x);
assertEquals(a, b);