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
This commit is contained in:
parent
4b5ca4f396
commit
55bdf90f60
@ -1,66 +0,0 @@
|
||||
// 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 @@
|
||||
#include "src/v8.h"
|
||||
|
||||
#include "src/arguments.h"
|
||||
#include "src/base/bits.h"
|
||||
#include "src/bootstrapper.h"
|
||||
#include "src/codegen.h"
|
||||
#include "src/misc-intrinsics.h"
|
||||
#include "src/runtime/runtime-utils.h"
|
||||
|
||||
|
||||
@ -525,11 +525,11 @@ RUNTIME_FUNCTION(Runtime_SmiLexicographicCompare) {
|
||||
// integer comes first in the lexicographic order.
|
||||
|
||||
// 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;
|
||||
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;
|
||||
y_log10 -= y_scaled < kPowersOf10[y_log10];
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user