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inline asm mmx: how to movq from memory to %mmX


following up on my previous post...

i am trying to do some vector addition using MMX and inline assembly
in GCC.  my code follows.

i want the function 'simd' to do the same as 'sisd'

i get these errors when i try to compile:

[jack@fedora i]$ gcc -mmmx v.c
/tmp/ccWXntVc.s: Assembler messages:
/tmp/ccWXntVc.s:19: Error: suffix or operands invalid for `movq'
/tmp/ccWXntVc.s:20: Error: junk `%mm0' after register

[jack@fedora i]$ gcc -v
Using built-in specs.
Target: i386-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/u
sr/share/info --enable-shared --enable-threads=posix --enable-checking=release -
-with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-
libgcj-multifile --enable-languages=c,c++,objc,obj-c++,java,fortran,ada --enable
-java-awt=gtk --disable-dssi --with-java-home=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.
0/jre --with-cpu=generic --host=i386-redhat-linux
Thread model: posix
gcc version 4.1.0 20060304 (Red Hat 4.1.0-3)


[jack@fedora i]$ cat v.c #include <string.h> #include <stdio.h> #include <stdlib.h>

typedef long I;
typedef char C;
#define IZ sizeof(I)
#define W 2

simd(n, is)
I *is;
{   I i;
   asm("pxor %mm0,%mm0");
   for (i=0; i < n; i += W) {
       asm("movq %0 %%mm1\n\t"
           "paddq %%mm1 %%mm0"
           :
           :"m"(is[i])           );
   }
   return 0;
}

sisd(n, is)
I *is;
{
   I i = 0, j = 0;
   for (i = 0; i < n; i++)
       j += is[i];
   return j;
}

main(c, v)
C **v;
{
   I n = atol(v[1]),
       z = atol(v[2]), m = atol(v[3]), *is = malloc(IZ * (z *= W));
   I result;
   printf("IZ=%d, %s\n",IZ,m?"SIMD":"SISD");
   while (n--)
       result=m?simd(z, is):sisd(z, is);
   printf("%d\n",result);
}


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