Commit 55bdf90f authored by bmeurer@chromium.org's avatar bmeurer@chromium.org

Drop obsolete misc-intrinsics.h file.

R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/648643003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24742 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
parent 4b5ca4f3
// Copyright 2011 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_MISC_INTRINSICS_H_
#define V8_MISC_INTRINSICS_H_
#include "include/v8.h"
#include "src/globals.h"
namespace v8 {
namespace internal {
// Returns the index of the leading 1 bit, counting the least significant bit at
// index 0. (1 << IntegerLog2(x)) is a mask for the most significant bit of x.
// Result is undefined if input is zero.
int IntegerLog2(uint32_t value);
#if defined(__GNUC__)
inline int IntegerLog2(uint32_t value) {
return 31 - __builtin_clz(value);
}
#elif defined(_MSC_VER)
#pragma intrinsic(_BitScanReverse)
inline int IntegerLog2(uint32_t value) {
unsigned long result; // NOLINT: MSVC intrinsic demands this type.
_BitScanReverse(&result, value);
return result;
}
#else
// Default version using regular operations. Code taken from:
// http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog
inline int IntegerLog2(uint32_t value) {
int result, shift;
shift = (value > 0xFFFF) << 4;
value >>= shift;
result = shift;
shift = (value > 0xFF) << 3;
value >>= shift;
result |= shift;
shift = (value > 0xF) << 2;
value >>= shift;
result |= shift;
shift = (value > 0x3) << 1;
value >>= shift;
result |= shift;
result |= (value >> 1);
return result;
}
#endif
} } // namespace v8::internal
#endif // V8_MISC_INTRINSICS_H_
...@@ -5,9 +5,9 @@ ...@@ -5,9 +5,9 @@
#include "src/v8.h" #include "src/v8.h"
#include "src/arguments.h" #include "src/arguments.h"
#include "src/base/bits.h"
#include "src/bootstrapper.h" #include "src/bootstrapper.h"
#include "src/codegen.h" #include "src/codegen.h"
#include "src/misc-intrinsics.h"
#include "src/runtime/runtime-utils.h" #include "src/runtime/runtime-utils.h"
...@@ -525,11 +525,11 @@ RUNTIME_FUNCTION(Runtime_SmiLexicographicCompare) { ...@@ -525,11 +525,11 @@ RUNTIME_FUNCTION(Runtime_SmiLexicographicCompare) {
// integer comes first in the lexicographic order. // integer comes first in the lexicographic order.
// From http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10 // From http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10
int x_log2 = IntegerLog2(x_scaled); int x_log2 = 31 - base::bits::CountLeadingZeros32(x_scaled);
int x_log10 = ((x_log2 + 1) * 1233) >> 12; int x_log10 = ((x_log2 + 1) * 1233) >> 12;
x_log10 -= x_scaled < kPowersOf10[x_log10]; x_log10 -= x_scaled < kPowersOf10[x_log10];
int y_log2 = IntegerLog2(y_scaled); int y_log2 = 31 - base::bits::CountLeadingZeros32(y_scaled);
int y_log10 = ((y_log2 + 1) * 1233) >> 12; int y_log10 = ((y_log2 + 1) * 1233) >> 12;
y_log10 -= y_scaled < kPowersOf10[y_log10]; y_log10 -= y_scaled < kPowersOf10[y_log10];
......
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