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FixedDiv using integers

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BUG=250
TEST=fixed div unittest
R=dingkai@google.com, ryanpetrie@google.com

Review URL: https://webrtc-codereview.appspot.com/1681004

git-svn-id: http://libyuv.googlecode.com/svn/trunk@732 16f28f9a-4ce2-e073-06de-1de4eb20be90
This commit is contained in:
fbarchard@google.com 2013-06-18 17:12:15 +00:00
parent 1140454596
commit 747ceb9fa5
6 changed files with 740 additions and 709 deletions
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2
README.chromium
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@ -1,6 +1,6 @@
Name: libyuv
URL: http://code.google.com/p/libyuv/
Version: 731
Version: 732
License: BSD
License File: LICENSE

16
include/libyuv/row.h
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@ -130,6 +130,7 @@ extern "C" {
// TODO(fbarchard): Port to gcc.
#if !defined(LIBYUV_DISABLE_X86) && defined(_M_IX86) && defined(_MSC_VER)
#define HAS_ARGBCOLORTABLEROW_X86
#define HAS_FIXEDDIV
// Visual C 2012 required for AVX2.
#if _MSC_VER >= 1700
#define HAS_ARGBSHUFFLEROW_AVX2
@ -1516,16 +1517,13 @@ void SobelXYRow_SSE2(const uint8* src_sobelx, const uint8* src_sobely,
uint8* dst_argb, int width);
void SobelXYRow_NEON(const uint8* src_sobelx, const uint8* src_sobely,
uint8* dst_argb, int width);
extern const float kRecipTable[4097];
// Divide num by div and return value as 16.16 fixed point.
#ifdef __cplusplus
static __inline int FixedDiv(int num, int div) {
if (static_cast<unsigned int>(div) <= 4096u) {
return static_cast<int>(num * kRecipTable[div]);
}
return static_cast<int>((static_cast<int64>(num) << 16) / div);
}
// Divide num by div and return as 16.16 fixed point result.
int FixedDiv_C(int num, int div);
#ifdef HAS_FIXEDDIV
int FixedDiv(int num, int div);
#else
#define FixedDiv FixedDiv_C
#endif
#ifdef __cplusplus

2
include/libyuv/version.h
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@ -11,6 +11,6 @@
#ifndef INCLUDE_LIBYUV_VERSION_H_ // NOLINT
#define INCLUDE_LIBYUV_VERSION_H_
#define LIBYUV_VERSION 731
#define LIBYUV_VERSION 732
#endif // INCLUDE_LIBYUV_VERSION_H_ NOLINT

1380
source/row_common.cc
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File diff suppressed because it is too large Load Diff

24
source/row_win.cc
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@ -6602,6 +6602,30 @@ void I422ToUYVYRow_SSE2(const uint8* src_y,
ret
}
}
// Fixed point 0.32 reciprocal table.
extern const uint32 kRecipTable[4097];
// Divide num by div and return as 16.16 fixed point result.
__declspec(naked) __declspec(align(16))
int FixedDiv(int num, int div) {
__asm {
mov eax, [esp + 4] // num
mov ecx, [esp + 8] // div
cmp ecx, 4096
ja largediv
mul dword ptr kRecipTable[ecx * 4]
shrd eax, edx, 16
ret
largediv:
cwd // extend num to 64 bits
shld edx, eax, 16
shl eax, 16
idiv ecx
ret
}
}
#endif // !defined(LIBYUV_DISABLE_X86) && defined(_M_IX86) && defined(_MSC_VER)
#ifdef __cplusplus

25
unit_test/math_test.cc
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@ -12,16 +12,12 @@
#include <string.h>
#include "libyuv/basic_types.h"
#include "libyuv/cpu_id.h"
#include "libyuv/row.h"
#include "../unit_test/unit_test.h"
namespace libyuv {
// Divide num by div and return value as 16.16 fixed point.
static int FixedDiv_C(int num, int div) {
return static_cast<int>((static_cast<int64>(num) << 16) / div);
}
TEST_F(libyuvTest, TestFixedDiv) {
int num[256];
int div[256];
@ -43,7 +39,7 @@ TEST_F(libyuvTest, TestFixedDiv) {
}
for (int j = 0; j < 256; ++j) {
result_c[j] = libyuv::FixedDiv_C(num[j], div[j]);
EXPECT_NEAR(result_c[j], result_opt[j], 3);
EXPECT_NEAR(result_c[j], result_opt[j], 1);
}
}
@ -64,8 +60,7 @@ TEST_F(libyuvTest, TestFixedDiv_Opt) {
EXPECT_EQ(0x20000, libyuv::FixedDiv(960 * 2, 960));
EXPECT_EQ(0x08000, libyuv::FixedDiv(640 / 2, 640));
EXPECT_EQ(0x04000, libyuv::FixedDiv(640 / 4, 640));
// TODO(fbarchard): Improve accuracy for divides should be exact.
EXPECT_NEAR(0x20000, libyuv::FixedDiv(1080 * 2, 1080), 1);
EXPECT_EQ(0x20000, libyuv::FixedDiv(1080 * 2, 1080));
srandom(time(NULL));
MemRandomize(reinterpret_cast<uint8*>(&num[0]), sizeof(num));
@ -77,14 +72,22 @@ TEST_F(libyuvTest, TestFixedDiv_Opt) {
div[j] = 1280;
}
}
int has_x86 = TestCpuFlag(kCpuHasX86);
for (int i = 0; i < benchmark_pixels_div256_; ++i) {
for (int j = 0; j < 256; ++j) {
result_opt[j] = libyuv::FixedDiv(num[j], div[j]);
if (has_x86) {
for (int j = 0; j < 256; ++j) {
result_opt[j] = libyuv::FixedDiv(num[j], div[j]);
}
} else {
for (int j = 0; j < 256; ++j) {
result_opt[j] = libyuv::FixedDiv_C(num[j], div[j]);
}
}
}
for (int j = 0; j < 256; ++j) {
result_c[j] = libyuv::FixedDiv_C(num[j], div[j]);
EXPECT_NEAR(result_c[j], result_opt[j], 3);
EXPECT_NEAR(result_c[j], result_opt[j], 1);
}
}