blob: ba0fd22d92806224f175cfe44ad4e3682b1135a7 [file] [log] [blame]
/*
@author herumi
JPEG quantize sample
This program generates a quantization routine by using fast division algorithm in run-time.
time(sec)
quality 1(high) 10 50 100(low)
VC2005 8.0 8.0 8.0 8.0
Xbyak 1.6 0.8 0.5 0.5
; generated code at q = 1
push esi
push edi
mov edi,dword ptr [esp+0Ch]
mov esi,dword ptr [esp+10h]
mov eax,dword ptr [esi]
shr eax,4
mov dword ptr [edi],eax
mov eax,dword ptr [esi+4]
mov edx,0BA2E8BA3h
mul eax,edx
shr edx,3
...
; generated code at q = 100
push esi
push edi
mov edi,dword ptr [esp+0Ch]
mov esi,dword ptr [esp+10h]
mov eax,dword ptr [esi]
mov dword ptr [edi],eax
mov eax,dword ptr [esi+4]
mov dword ptr [edi+4],eax
mov eax,dword ptr [esi+8]
mov dword ptr [edi+8],eax
mov eax,dword ptr [esi+0Ch]
...
*/
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define XBYAK_NO_OP_NAMES
#include "xbyak/xbyak.h"
#ifdef _MSC_VER
#pragma warning(disable : 4996) // scanf
#endif
const int N = 64;
class Quantize : public Xbyak::CodeGenerator {
static int ilog2(int x)
{
int shift = 0;
while ((1 << shift) <= x) shift++;
return shift - 1;
}
public:
/*
input : esi
output : eax = [esi+offset] / dividend
destroy : edx
*/
void udiv(uint32_t dividend, int offset)
{
mov(eax, ptr[esi + offset]);
/* dividend = odd x 2^exponent */
int exponent = 0, odd = dividend;
while ((odd & 1) == 0) {
odd >>= 1; exponent++;
}
if (odd == 1) { // trivial case
if (exponent) {
shr(eax, exponent);
}
return;
}
uint64_t mLow, mHigh;
int len = ilog2(odd) + 1;
{
uint64_t roundUp = uint64_t(1) << (32 + len);
uint64_t k = roundUp / (0xFFFFFFFFL - (0xFFFFFFFFL % odd));
mLow = roundUp / odd;
mHigh = (roundUp + k) / odd;
}
while (((mLow >> 1) < (mHigh >> 1)) && (len > 0)) {
mLow >>= 1; mHigh >>= 1; len--;
}
uint64_t m; int a;
if ((mHigh >> 32) == 0) {
m = mHigh; a = 0;
} else {
len = ilog2(odd);
uint64_t roundDown = uint64_t(1) << (32 + len);
mLow = roundDown / odd;
int r = (int)(roundDown % odd);
m = (r <= (odd >> 1)) ? mLow : mLow + 1;
a = 1;
}
while ((m & 1) == 0) {
m >>= 1; len--;
}
len += exponent;
mov(edx, int(m));
mul(edx);
if (a) {
add(eax, int(m));
adc(edx, 0);
}
if (len) {
shr(edx, len);
}
mov(eax, edx);
}
/*
quantize(uint32_t dest[64], const uint32_t src[64]);
*/
Quantize(const uint32_t qTbl[64])
{
push(esi);
push(edi);
const int P_ = 4 * 2;
mov(edi, ptr [esp+P_+4]); // dest
mov(esi, ptr [esp+P_+8]); // src
for (int i = 0; i < N; i++) {
udiv(qTbl[i], i * 4);
mov(ptr[edi+i*4], eax);
}
pop(edi);
pop(esi);
ret();
}
};
void quantize(uint32_t dest[64], const uint32_t src[64], const uint32_t qTbl[64])
{
for (int i = 0; i < N; i++) {
dest[i] = src[i] / qTbl[i];
}
}
#ifdef XBYAK64
int main()
{
puts("not implemented for 64bit");
return 1;
}
#else
int main(int argc, char *argv[])
{
int q;
if (argc > 1) {
q = atoi(argv[1]);
} else {
printf("input quantize=");
if (scanf("%d", &q) != 1) {
fprintf(stderr, "bad number\n");
return 1;
}
}
printf("q=%d\n", q);
uint32_t qTbl[] = {
16, 11, 10, 16, 24, 40, 51, 61,
12, 12, 14, 19, 26, 58, 60, 55,
14, 13, 16, 24, 40, 57, 69, 56,
14, 17, 22, 29, 51, 87, 80, 62,
18, 22, 37, 56, 68, 109, 103, 77,
24, 35, 55, 64, 81, 104, 113, 92,
49, 64, 78, 87, 103, 121, 120, 101,
72, 92, 95, 98, 112, 100, 103, 99
};
for (int i = 0; i < N; i++) {
qTbl[i] /= q;
if (qTbl[i] == 0) qTbl[i] = 1;
}
try {
uint32_t src[N];
uint32_t dest[N];
uint32_t dest2[N];
for (int i = 0; i < N; i++) {
src[i] = rand() % 2048;
}
Quantize jit(qTbl);
//printf("jit size=%d, ptr=%p\n", jit.getSize(), jit.getCode());
void (*quantize2)(uint32_t*, const uint32_t*, const uint32_t *) = jit.getCode<void (*)(uint32_t*, const uint32_t*, const uint32_t *)>();
quantize(dest, src, qTbl);
quantize2(dest2, src, qTbl);
for (int i = 0; i < N; i++) {
if (dest[i] != dest2[i]) {
printf("err[%d] %u %u\n", i, dest[i], dest2[i]);
}
}
const int count = 10000000;
int begin;
begin = clock();
for (int i = 0; i < count; i++) {
quantize(dest, src, qTbl);
}
printf("time=%.1fsec\n", (clock() - begin) / double(CLOCKS_PER_SEC));
begin = clock();
for (int i = 0; i < count; i++) {
quantize2(dest, src, qTbl);
}
printf("time=%.1fsec\n", (clock() - begin) / double(CLOCKS_PER_SEC));
} catch (std::exception& e) {
printf("ERR:%s\n", e.what());
} catch (...) {
printf("unknown error\n");
}
}
#endif