学习BLAS库 -- DOT
函数语法:
XDOT( N, X, INCX, Y, INCY)
功能：
Computes the dot product of two vectors.
dot <- X^{T}Y
参数：
X: S(single float), D(double float), DS
N: vector dimension
X: vector x
INCX: spacing between elements of x
Y: vector y
INCY: spacing between elements of y
Fortran语言版DDOT
源代码 ： DOUBLE PRECISION FUNCTION DDOT(N,DX,INCX,DY,INCY)
* .. Scalar Arguments ..
INTEGER INCX,INCY,N
* ..
* .. Array Arguments ..
DOUBLE PRECISION DX(*),DY(*)
* ..
*
* Purpose
* =======
*
* forms the dot product of two vectors.
* uses unrolled loops for increments equal to one.
* jack dongarra, linpack, 3/11/78.
* modified 12/3/93, array(1) declarations changed to array(*)
*
*
* .. Local Scalars ..
DOUBLE PRECISION DTEMP
INTEGER I,IX,IY,M,MP1
* ..
* .. Intrinsic Functions ..
INTRINSIC MOD
* ..
DDOT = 0.0d0
DTEMP = 0.0d0
IF (N.LE.0) RETURN
IF (INCX.EQ.1 .AND. INCY.EQ.1) GO TO 20
*
* code for unequal increments or equal increments
* not equal to 1
*
IX = 1
IY = 1
IF (INCX.LT.0) IX = (-N+1)*INCX + 1
IF (INCY.LT.0) IY = (-N+1)*INCY + 1
DO 10 I = 1,N
DTEMP = DTEMP + DX(IX)*DY(IY)
IX = IX + INCX
IY = IY + INCY
10 CONTINUE
DDOT = DTEMP
RETURN
*
* code for both increments equal to 1
*
*
* clean-up loop
*
20 M = MOD(N,5)
IF (M.EQ.0) GO TO 40
DO 30 I = 1,M
DTEMP = DTEMP + DX(I)*DY(I)
30 CONTINUE
IF (N.LT.5) GO TO 60
40 MP1 = M + 1
DO 50 I = MP1,N,5
DTEMP = DTEMP + DX(I)*DY(I) + DX(I+1)*DY(I+1) +
+ DX(I+2)*DY(I+2) + DX(I+3)*DY(I+3) + DX(I+4)*DY(I+4)
50 CONTINUE
60 DDOT = DTEMP
RETURN
END
C语言版(f2c)DDOT
源代码 ：/* -- translated by f2c (version 19940927).
You must link the resulting object file with the libraries:
-lf2c -lm (in that order)
*/
#include "f2c.h"
doublereal ddot_(integer *n, doublereal *dx, integer *incx, doublereal *dy,
integer *incy)
{
/* System generated locals */
integer i__1;
doublereal ret_val;
/* Local variables */
static integer i, m;
static doublereal dtemp;
static integer ix, iy, mp1;
/* forms the dot product of two vectors.
uses unrolled loops for increments equal to one.
jack dongarra, linpack, 3/11/78.
modified 12/3/93, array(1) declarations changed to array(*)
Parameter adjustments
Function Body */
#define DY(I) dy[(I)-1]
#define DX(I) dx[(I)-1]
ret_val = 0.;
dtemp = 0.;
if (*n <= 0) {
return ret_val;
}
if (*incx == 1 && *incy == 1) {
goto L20;
}
/* code for unequal increments or equal increments
not equal to 1 */
ix = 1;
iy = 1;
if (*incx < 0) {
ix = (-(*n) + 1) * *incx + 1;
}
if (*incy < 0) {
iy = (-(*n) + 1) * *incy + 1;
}
i__1 = *n;
for (i = 1; i <= *n; ++i) {
dtemp += DX(ix) * DY(iy);
ix += *incx;
iy += *incy;
/* L10: */
}
ret_val = dtemp;
return ret_val;
/* code for both increments equal to 1
clean-up loop */
L20:
m = *n % 5;
if (m == 0) {
goto L40;
}
i__1 = m;
for (i = 1; i <= m; ++i) {
dtemp += DX(i) * DY(i);
/* L30: */
}
if (*n < 5) {
goto L60;
}
L40:
mp1 = m + 1;
i__1 = *n;
for (i = mp1; i <= *n; i += 5) {
dtemp = dtemp + DX(i) * DY(i) + DX(i + 1) * DY(i + 1) + DX(i + 2) *
DY(i + 2) + DX(i + 3) * DY(i + 3) + DX(i + 4) * DY(i + 4);
/* L50: */
}
L60:
ret_val = dtemp;
return ret_val;
} /* ddot_ */C语言版DDOT
源代码 ：/*
* cblas_ddot.c
*
* The program is a C version of ddot.
* All right reserved.
*/
double cblas_ddot(const int N, const double *X, const int incX,
const double *Y, const int incY)
{
int i;
int m;
int mp1;
double result = 0.0;
if (N < 0)
{
return result;
}
if ((incX != 1) || (incY != 1))
{
int ix = 1;
int iy = 1;
if (incX < 0)
{
ix = (1 - N) * incX + 1;
}
if (incY < 0)
{
iy = (1 - N) * incY + 1;
}
for (i = 0; i < N; i++)
{
result += Y[iy] * X[ix];
ix = ix + incX;
iy = iy + incY;
}
return result;
}
m = (N % 5);
if (0 != m)
{
for (i = 0; i < m; i++)
{
result += Y[i] * X[i];
}
if (N < 5)
{
return result;
}
}
mp1 = m ;
for (i = mp1; i < N; i += 5)
{
result += (Y[i] * X[i] + Y[i + 1] * X[i + 1] + Y[i + 2] * X[i + 2]
+ Y[i + 3] * X[i + 3] + Y[i + 4] * X[i + 4]);
}
return result;
}
汇编语言版(VC )DDOT
源代码 ：_TEXT SEGMENT
_iy$4493 = -32 ; size = 4
_ix$4492 = -28 ; size = 4
_m$ = -24 ; size = 4
_mp1$ = -20 ; size = 4
_result$ = -16 ; size = 8
_i$ = -4 ; size = 4
_N$ = 8 ; size = 4
_X$ = 12 ; size = 4
_incX$ = 16 ; size = 4
_Y$ = 20 ; size = 4
_incY$ = 24 ; size = 4
_cblas_ddot PROC
; Line 15
push ebp
mov ebp, esp
sub esp, 32 ; 00000020H
push esi
; Line 18
mov DWORD PTR _mp1$[ebp], 0
; Line 19
fldz
fstp QWORD PTR _result$[ebp]
; Line 20
cmp DWORD PTR _N$[ebp], 0
jge SHORT $LN16@cblas_ddot
; Line 22
fld QWORD PTR _result$[ebp]
jmp $LN17@cblas_ddot
$LN16@cblas_ddot:
; Line 26
cmp DWORD PTR _incX$[ebp], 1
jne SHORT $LN14@cblas_ddot
cmp DWORD PTR _incY$[ebp], 1
je $LN15@cblas_ddot
$LN14@cblas_ddot:
; Line 28
mov DWORD PTR _ix$4492[ebp], 1
; Line 29
mov DWORD PTR _iy$4493[ebp], 1
; Line 30
cmp DWORD PTR _incX$[ebp], 0
jge SHORT $LN13@cblas_ddot
; Line 32
mov eax, 1
sub eax, DWORD PTR _N$[ebp]
imul eax, DWORD PTR _incX$[ebp]
add eax, 1
mov DWORD PTR _ix$4492[ebp], eax
$LN13@cblas_ddot:
; Line 34
cmp DWORD PTR _incY$[ebp], 0
jge SHORT $LN12@cblas_ddot
; Line 36
mov ecx, 1
sub ecx, DWORD PTR _N$[ebp]
imul ecx, DWORD PTR _incY$[ebp]
add ecx, 1
mov DWORD PTR _iy$4493[ebp], ecx
$LN12@cblas_ddot:
; Line 38
mov DWORD PTR _i$[ebp], 0
jmp SHORT $LN11@cblas_ddot
$LN10@cblas_ddot:
mov edx, DWORD PTR _i$[ebp]
add edx, 1
mov DWORD PTR _i$[ebp], edx
$LN11@cblas_ddot:
mov eax, DWORD PTR _i$[ebp]
cmp eax, DWORD PTR _N$[ebp]
jge SHORT $LN9@cblas_ddot
; Line 40
mov ecx, DWORD PTR _iy$4493[ebp]
mov edx, DWORD PTR _Y$[ebp]
mov eax, DWORD PTR _ix$4492[ebp]
mov esi, DWORD PTR _X$[ebp]
fld QWORD PTR [edx+ecx*8]
fmul QWORD PTR [esi+eax*8]
fadd QWORD PTR _result$[ebp]
fstp QWORD PTR _result$[ebp]
; Line 41
mov ecx, DWORD PTR _ix$4492[ebp]
add ecx, DWORD PTR _incX$[ebp]
mov DWORD PTR _ix$4492[ebp], ecx
; Line 42
mov edx, DWORD PTR _iy$4493[ebp]
add edx, DWORD PTR _incY$[ebp]
mov DWORD PTR _iy$4493[ebp], edx
; Line 43
jmp SHORT $LN10@cblas_ddot
$LN9@cblas_ddot:
; Line 44
fld QWORD PTR _result$[ebp]
jmp $LN17@cblas_ddot
$LN15@cblas_ddot:
; Line 47
mov eax, DWORD PTR _N$[ebp]
cdq
mov ecx, 5
idiv ecx
mov DWORD PTR _m$[ebp], edx
; Line 49
cmp DWORD PTR _m$[ebp], 0
je SHORT $LN4@cblas_ddot
; Line 51
mov DWORD PTR _i$[ebp], 0
jmp SHORT $LN7@cblas_ddot
$LN6@cblas_ddot:
mov edx, DWORD PTR _i$[ebp]
add edx, 1
mov DWORD PTR _i$[ebp], edx
$LN7@cblas_ddot:
mov eax, DWORD PTR _i$[ebp]
cmp eax, DWORD PTR _m$[ebp]
jge SHORT $LN5@cblas_ddot
; Line 53
mov ecx, DWORD PTR _i$[ebp]
mov edx, DWORD PTR _Y$[ebp]
mov eax, DWORD PTR _i$[ebp]
mov esi, DWORD PTR _X$[ebp]
fld QWORD PTR [edx+ecx*8]
fmul QWORD PTR [esi+eax*8]
fadd QWORD PTR _result$[ebp]
fstp QWORD PTR _result$[ebp]
; Line 54
jmp SHORT $LN6@cblas_ddot
$LN5@cblas_ddot:
; Line 55
cmp DWORD PTR _N$[ebp], 5
jge SHORT $LN4@cblas_ddot
; Line 57
fld QWORD PTR _result$[ebp]
jmp $LN17@cblas_ddot
$LN4@cblas_ddot:
; Line 61
mov ecx, DWORD PTR _m$[ebp]
mov DWORD PTR _mp1$[ebp], ecx
; Line 63
mov edx, DWORD PTR _mp1$[ebp]
mov DWORD PTR _i$[ebp], edx
jmp SHORT $LN3@cblas_ddot
$LN2@cblas_ddot:
mov eax, DWORD PTR _i$[ebp]
add eax, 5
mov DWORD PTR _i$[ebp], eax
$LN3@cblas_ddot:
mov ecx, DWORD PTR _i$[ebp]
cmp ecx, DWORD PTR _N$[ebp]
jge SHORT $LN1@cblas_ddot
; Line 66
mov edx, DWORD PTR _i$[ebp]
mov eax, DWORD PTR _Y$[ebp]
mov ecx, DWORD PTR _i$[ebp]
mov esi, DWORD PTR _X$[ebp]
fld QWORD PTR [eax+edx*8]
fmul QWORD PTR [esi+ecx*8]
mov edx, DWORD PTR _i$[ebp]
mov eax, DWORD PTR _Y$[ebp]
mov ecx, DWORD PTR _i$[ebp]
mov esi, DWORD PTR _X$[ebp]
fld QWORD PTR [eax+edx*8+8]
fmul QWORD PTR [esi+ecx*8+8]
faddp ST(1), ST(0)
mov edx, DWORD PTR _i$[ebp]
mov eax, DWORD PTR _Y$[ebp]
mov ecx, DWORD PTR _i$[ebp]
mov esi, DWORD PTR _X$[ebp]
fld QWORD PTR [eax+edx*8+16]
fmul QWORD PTR [esi+ecx*8+16]
faddp ST(1), ST(0)
mov edx, DWORD PTR _i$[ebp]
mov eax, DWORD PTR _Y$[ebp]
mov ecx, DWORD PTR _i$[ebp]
mov esi, DWORD PTR _X$[ebp]
fld QWORD PTR [eax+edx*8+24]
fmul QWORD PTR [esi+ecx*8+24]
faddp ST(1), ST(0)
mov edx, DWORD PTR _i$[ebp]
mov eax, DWORD PTR _Y$[ebp]
mov ecx, DWORD PTR _i$[ebp]
mov esi, DWORD PTR _X$[ebp]
fld QWORD PTR [eax+edx*8+32]
fmul QWORD PTR [esi+ecx*8+32]
faddp ST(1), ST(0)
fadd QWORD PTR _result$[ebp]
fstp QWORD PTR _result$[ebp]
; Line 71
jmp $LN2@cblas_ddot
$LN1@cblas_ddot:
; Line 73
fld QWORD PTR _result$[ebp]
$LN17@cblas_ddot:
; Line 75
pop esi
mov esp, ebp
pop ebp
ret 0
_cblas_ddot ENDP
_TEXT ENDS编译参数：
cl main.c汇编语言版(VC, 计算速度优化 )DDOT
源代码 ：; COMDAT _cblas_ddot
_TEXT SEGMENT
_i$ = -12 ; size = 4
_result$ = -8 ; size = 8
tv1489 = 8 ; size = 4
tv683 = 8 ; size = 4
_N$ = 8 ; size = 4
_X$ = 12 ; size = 4
_incX$ = 16 ; size = 4
_Y$ = 20 ; size = 4
_incY$ = 24 ; size = 4
_cblas_ddot PROC ; COMDAT
; Line 15
sub esp, 12 ; 0000000cH
; Line 19
xorps xmm1, xmm1
push edi
; Line 20
mov edi, DWORD PTR _N$[esp+12]
movsd QWORD PTR _result$[esp+16], xmm1
test edi, edi
jns SHORT $LN16@cblas_ddot
; Line 22
fldz
pop edi
; Line 75
add esp, 12 ; 0000000cH
ret 0
$LN16@cblas_ddot:
; Line 26
mov edx, DWORD PTR _incX$[esp+12]
push ebx
push ebp
push esi
mov esi, DWORD PTR _incY$[esp+24]
cmp edx, 1
jne $LN14@cblas_ddot
cmp esi, 1
jne $LN14@cblas_ddot
; Line 49
mov ebp, DWORD PTR _Y$[esp+24]
mov eax, 1717986919 ; 66666667H
imul edi
sar edx, 1
mov eax, edx
shr eax, 31 ; 0000001fH
add eax, edx
lea eax, DWORD PTR [eax+eax*4]
mov ebx, edi
sub ebx, eax
je $LN32@cblas_ddot
; Line 51
xor esi, esi
cmp ebx, 4
jl SHORT $LC26@cblas_ddot
mov edx, DWORD PTR _X$[esp+24]
lea ecx, DWORD PTR [edx+24]
; Line 53
sub edx, ebp
mov DWORD PTR tv683[esp+24], edx
lea edx, DWORD PTR [ebx-4]
shr edx, 2
inc edx
lea esi, DWORD PTR [edx*4]
mov DWORD PTR _i$[esp+28], esi
mov esi, DWORD PTR tv683[esp+24]
lea eax, DWORD PTR [ebp+8]
npad 9
$LL27@cblas_ddot:
movsd xmm0, QWORD PTR [eax-8]
mulsd xmm0, QWORD PTR [ecx-24]
addsd xmm0, xmm1
movsd xmm1, QWORD PTR [esi+eax]
mulsd xmm1, QWORD PTR [eax]
addsd xmm0, xmm1
movsd xmm1, QWORD PTR [eax+8]
mulsd xmm1, QWORD PTR [ecx-8]
addsd xmm0, xmm1
movsd xmm1, QWORD PTR [eax+16]
mulsd xmm1, QWORD PTR [ecx]
add eax, 32 ; 00000020H
add ecx, 32 ; 00000020H
dec edx
addsd xmm1, xmm0
jne SHORT $LL27@cblas_ddot
mov esi, DWORD PTR _i$[esp+28]
movsd QWORD PTR _result$[esp+28], xmm1
$LC26@cblas_ddot:
; Line 51
cmp esi, ebx
jge SHORT $LN31@cblas_ddot
mov edx, DWORD PTR _X$[esp+24]
mov ecx, ebx
sub edx, ebp
lea eax, DWORD PTR [ebp+esi*8]
sub ecx, esi
npad 5
$LC7@cblas_ddot:
; Line 53
movsd xmm0, QWORD PTR [eax+edx]
mulsd xmm0, QWORD PTR [eax]
add eax, 8
dec ecx
addsd xmm1, xmm0
jne SHORT $LC7@cblas_ddot
movsd QWORD PTR _result$[esp+28], xmm1
$LN31@cblas_ddot:
; Line 55
cmp edi, 5
; Line 57
jl $LN28@cblas_ddot
$LN32@cblas_ddot:
; Line 63
cmp ebx, edi
jge $LN28@cblas_ddot
mov eax, DWORD PTR _X$[esp+24]
lea esi, DWORD PTR [eax+ebx*8+24]
sub eax, ebp
sub edi, ebx
mov DWORD PTR tv683[esp+24], eax
dec edi
mov eax, -858993459 ; cccccccdH
mul edi
shr edx, 2
lea ecx, DWORD PTR [ebp+ebx*8+8]
inc edx
npad 6
$LL3@cblas_ddot:
; Line 66
mov eax, DWORD PTR tv683[esp+24]
movsd xmm0, QWORD PTR [ecx-8]
mulsd xmm0, QWORD PTR [esi-24]
movsd xmm2, QWORD PTR [eax+ecx]
mulsd xmm2, QWORD PTR [ecx]
addsd xmm0, xmm2
movsd xmm2, QWORD PTR [ecx+8]
mulsd xmm2, QWORD PTR [esi-8]
addsd xmm0, xmm2
movsd xmm2, QWORD PTR [ecx+16]
mulsd xmm2, QWORD PTR [esi]
addsd xmm0, xmm2
movsd xmm2, QWORD PTR [ecx+24]
mulsd xmm2, QWORD PTR [esi+8]
add ecx, 40 ; 00000028H
add esi, 40 ; 00000028H
dec edx
addsd xmm0, xmm2
addsd xmm1, xmm0
jne SHORT $LL3@cblas_ddot
; Line 40
pop esi
pop ebp
movsd QWORD PTR _result$[esp+20], xmm1
; Line 44
fld QWORD PTR _result$[esp+20]
pop ebx
pop edi
; Line 75
add esp, 12 ; 0000000cH
ret 0
$LN14@cblas_ddot:
; Line 28
mov eax, 1
; Line 29
mov ecx, eax
; Line 30
test edx, edx
jns SHORT $LN13@cblas_ddot
; Line 32
sub eax, edi
imul eax, edx
inc eax
$LN13@cblas_ddot:
; Line 34
test esi, esi
jns SHORT $LN12@cblas_ddot
; Line 36
sub ecx, edi
imul ecx, esi
inc ecx
$LN12@cblas_ddot:
; Line 38
mov ebx, DWORD PTR _Y$[esp+24]
xor ebp, ebp
cmp edi, 4
jl SHORT $LC29@cblas_ddot
lea ebp, DWORD PTR [edi-4]
shr ebp, 2
inc ebp
mov DWORD PTR tv1489[esp+24], ebp
add ebp, ebp
add ebp, ebp
mov DWORD PTR _i$[esp+28], ebp
npad 4
$LL30@cblas_ddot:
; Line 40
mov ebp, DWORD PTR _X$[esp+24]
movsd xmm0, QWORD PTR [ebp+eax*8]
mulsd xmm0, QWORD PTR [ebx+ecx*8]
addsd xmm0, xmm1
; Line 41
add eax, edx
movsd xmm1, QWORD PTR [ebp+eax*8]
; Line 42
add ecx, esi
mulsd xmm1, QWORD PTR [ebx+ecx*8]
addsd xmm1, xmm0
add eax, edx
movsd xmm0, QWORD PTR [ebp+eax*8]
add ecx, esi
mulsd xmm0, QWORD PTR [ebx+ecx*8]
add eax, edx
addsd xmm0, xmm1
movsd xmm1, QWORD PTR [ebp+eax*8]
add ecx, esi
mulsd xmm1, QWORD PTR [ebx+ecx*8]
add eax, edx
add ecx, esi
dec DWORD PTR tv1489[esp+24]
addsd xmm1, xmm0
jne SHORT $LL30@cblas_ddot
; Line 40
mov ebp, DWORD PTR _i$[esp+28]
movsd QWORD PTR _result$[esp+28], xmm1
$LC29@cblas_ddot:
; Line 38
cmp ebp, edi
jge SHORT $LN28@cblas_ddot
add esi, esi
add edx, edx
add esi, esi
add edx, edx
lea ecx, DWORD PTR [ebx+ecx*8]
mov ebx, DWORD PTR _X$[esp+24]
add esi, esi
add edx, edx
lea eax, DWORD PTR [ebx+eax*8]
sub edi, ebp
npad 4
$LC11@cblas_ddot:
; Line 40
movsd xmm0, QWORD PTR [ecx]
mulsd xmm0, QWORD PTR [eax]
; Line 41
add eax, edx
; Line 42
add ecx, esi
dec edi
addsd xmm1, xmm0
jne SHORT $LC11@cblas_ddot
; Line 40
movsd QWORD PTR _result$[esp+28], xmm1
$LN28@cblas_ddot:
; Line 44
fld QWORD PTR _result$[esp+28]
pop esi
pop ebp
pop ebx
pop edi
; Line 75
add esp, 12 ; 0000000cH
ret 0
_cblas_ddot ENDP
_TEXT ENDS启动编译器优化选项：
cl main.c /FA /O2 /arch:SSE2汇编语言版(GotoBLAS2库)DDOT
源代码 ：/*********************************************************************/
/* */
/* Optimized BLAS libraries */
/* By Kazushige Goto */
/* */
/* Copyright (c) The University of Texas, 2009. All rights reserved. */
/* UNIVERSITY EXPRESSLY DISCLAIMS ANY AND ALL WARRANTIES CONCERNING */
/* THIS SOFTWARE AND DOCUMENTATION, INCLUDING ANY WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR ANY PARTICULAR PURPOSE, */
/* NON-INFRINGEMENT AND WARRANTIES OF PERFORMANCE, AND ANY WARRANTY */
/* THAT MIGHT OTHERWISE ARISE FROM COURSE OF DEALING OR USAGE OF */
/* TRADE. NO WARRANTY IS EITHER EXPRESS OR IMPLIED WITH RESPECT TO */
/* THE USE OF THE SOFTWARE OR DOCUMENTATION. */
/* Under no circumstances shall University be liable for incidental, */
/* special, indirect, direct or consequential damages or loss of */
/* profits, interruption of business, or related expenses which may */
/* arise from use of Software or Documentation, including but not */
/* limited to those resulting from defects in Software and/or */
/* Documentation, or loss or inaccuracy of data of any kind. */
/*********************************************************************/
#define ASSEMBLER
#include "common.h"
#define STACK 12
#define ARGS 0
#define STACK_N 4 + STACK + ARGS(%esp)
#define STACK_X 8 + STACK + ARGS(%esp)
#define STACK_INCX 12 + STACK + ARGS(%esp)
#define STACK_Y 16 + STACK + ARGS(%esp)
#define STACK_INCY 20 + STACK + ARGS(%esp)
#define N %ebx
#define X %esi
#define INCX %ecx
#define Y %edi
#define INCY %edx
PROLOGUE
pushl %edi
pushl %esi
pushl %ebx
PROFCODE
#if defined(F_INTERFACE_GFORT) || defined(F_INTERFACE_G95)
EMMS
#endif
movl STACK_N, N
movl STACK_X, X
movl STACK_INCX, INCX
movl STACK_Y, Y
movl STACK_INCY, INCY
#ifdef F_INTERFACE
movl (N),N
movl (INCX),INCX
movl (INCY),INCY
#endif
leal (, INCX, SIZE), INCX
leal (, INCY, SIZE), INCY
fldz
fldz
fldz
fldz
cmpl $SIZE, INCX
jne .L14
cmpl $SIZE, INCY
jne .L14
movl N, %eax
sarl $2, %eax
jle .L15
ALIGN_3
.L16:
FLD 0 * SIZE(X)
FMUL 0 * SIZE(Y)
faddp %st,%st(1)
FLD 1 * SIZE(X)
FMUL 1 * SIZE(Y)
faddp %st,%st(2)
FLD 2 * SIZE(X)
FMUL 2 * SIZE(Y)
faddp %st,%st(3)
FLD 3 * SIZE(X)
FMUL 3 * SIZE(Y)
faddp %st,%st(4)
addl $4 * SIZE, X
addl $4 * SIZE, Y
decl %eax
jg .L16
ALIGN_3
.L15:
movl N, %eax
andl $3, %eax
jle .L27
ALIGN_3
.L22:
FLD (X)
addl $SIZE, X
FMUL (Y)
addl $SIZE, Y
faddp %st,%st(1)
decl %eax
jg .L22
jmp .L27
ALIGN_3
.L14:
#ifdef F_INTERFACE
testl INCX, INCX
jge .L28
movl N, %eax
decl %eax
imull INCX, %eax
subl %eax, X
ALIGN_3
.L28:
testl INCY, INCY
jge .L29
movl N, %eax
decl %eax
imull INCY, %eax
subl %eax, Y
ALIGN_3
.L29:
#endif
movl N, %eax
sarl $2, %eax
jle .L30
ALIGN_3
.L31:
FLD (X)
addl INCX, X
FMUL (Y)
addl INCY, Y
faddp %st,%st(1)
FLD (X)
addl INCX, X
FMUL (Y)
addl INCY, Y
faddp %st,%st(2)
FLD (X)
addl INCX, X
FMUL (Y)
addl INCY, Y
faddp %st,%st(3)
FLD (X)
addl INCX, X
FMUL (Y)
addl INCY, Y
faddp %st,%st(4)
decl %eax
jg .L31
ALIGN_3
.L30:
movl N, %eax
andl $3, %eax
jle .L27
ALIGN_3
.L37:
FLD (X)
addl INCX, X
FMUL (Y)
addl INCY, Y
faddp %st, %st(1)
decl %eax
jg .L37
ALIGN_3
.L27:
faddp %st,%st(2)
faddp %st,%st(2)
faddp %st,%st(1)
popl %ebx
popl %esi
popl %edi
ret
EPILOGUE
使用方法：
测试DDOT函数
unsigned int longGetCycleCount()
{
__asm RDTSC
}
void test_ddot()
{
int i;
int n = 19;
int inc1 = 1;
int inc2 = 1;
double result;
double X[] =
{ 1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1 };
double Y[] =
{ 12.1, 12.1, 12.1, 12.1, 12.1, 12.1, 12.1, 12.1, 12.1, 12.1, 12.1, 12.1, 12.1, 12.1, 12.1, 12.1, 12.1, 12.1, 12.1 };
char functionName[] = "ddot";
printf("================================================ \n");
printf("Testing BLAS library function -- %s \n", functionName);
for( i = 0; i < 100000; i++ )
{
result = cblas_ddot(n, X, inc1, Y, inc2);
}
printf("%s of the arraies is %f \n", functionName, result);
if (fabs(12.1 - result) < 0.0001)
{
printf("%s test SUCCESS.\n", functionName);
}
else
{
printf("[Fail] %s test failed.\n", functionName);
}
printf("\n");
return;
}
int main( void )
{
unsigned int start,end;
double cost;
start = longGetCycleCount();
test_ddot() ;
end = longGetCycleCount();
cost = (double) (end-start) / 2900000000 ;
printf("%f \n",cost);
return 0;
}未开启速度优化选项编译得到的运算时间 为0.005 秒左右。
开启速度优化选项编译得到的运算时间 为0.0005 秒左右。
开启编译器优化选项可使计算效率提高10倍左右。
测试环境：
Visual Studio Express 2010
Operating System：Windows 7, 64-bit
CPU：Intel Core(TM) CPU 2.90GHz
Memory： 4.00GB
Hard disk: 500G
参考文献
[1] http://www.applied-mathematics.net/miniSSEL1BLAS/miniSSEL1BLAS.pdf
[2] https://software.intel.com/en-us/articles/use-intriniscs/
[3] Hadi Brais. Compilers - What Every Programmer Should Know About Compiler Optimizations. https://msdn.microsoft.com/en-us/magazine/dn904673.aspx. February 2015.
[4] Koushik Ghosh. Writing Efficient C and C Code Optimization. http://www.codeproject.com/Articles/6154/Writing-Efficient-C-and-C-Code-Optimization. 26 Feb 2004.
[5] http://sci.tuomastonteri.fi/programming/sse
[6] https://www.kernel.org/pub/linux/kernel/people/geoff/cell/ps3-linux-docs/CellProgrammingTutorial/BasicsOfSIMDProgramming.html