[FFmpeg-devel] Hacks on FATE

[Michael Kostylev]

On Mon Jun 22 02:44:49 2009
David Conrad wrote:

>>> fix building with i386-*-gcc-3.3 -fPIC
>>>
>>> --- ffmpeg.orig/libavcodec/x86/cavsdsp_mmx.c
>>> +++ ffmpeg/libavcodec/x86/cavsdsp_mmx.c
>>> @@ -280,7 +280,7 @@
>>>         VOP(%%mm1, %%mm2, %%mm3, %%mm4, %%mm5, %%mm0, OP)\
>>>         \
>>>         : "+a"(src), "+c"(dst)\
>>> -        : "S"((x86_reg)srcStride), "r"((x86_reg)dstStride),  
>>> "m"(ADD), "m"(MUL1), "m"(MUL2)\
>>> +        : "S"((x86_reg)srcStride), "rm"((x86_reg)dstStride),  
>>> "m"(ADD), "m"(MUL1), "m"(MUL2)\
>>>         : "memory"\
>>>      );\
>>>      if(h==16){\
>>> @@ -295,7 +295,7 @@
>>>             VOP(%%mm3, %%mm4, %%mm5, %%mm0, %%mm1, %%mm2, OP)\
>>>             \
>>>            : "+a"(src), "+c"(dst)\
>>> -           : "S"((x86_reg)srcStride), "r"((x86_reg)dstStride),  
>>> "m"(ADD),  "m"(MUL1), "m"(MUL2)\
>>> +           : "S"((x86_reg)srcStride), "rm"((x86_reg)dstStride),  
>>> "m"(ADD),  "m"(MUL1), "m"(MUL2)\
>>>            : "memory"\
>>>         );\
>>>      }\
>> An 'm' constraint requires an lvalue operand (or ought to do (llvm
>> does)), which a cast expression is not.
> This happens to be the same exact same constraint that tripped up gcc on 
> OS X as well; if you instead change "a","c", and "S" (or some subset) to 
> "r", does it work?

Nope, it doesn't. That is what I started from.

> It shouldn't need an "m" constraint at all.

Note, what finally is %3 (gcc>=3.4):

QPEL_CAVSV1                             ff_put_cavs_qpel8_mc01_3dnow
...
"add %2, %0                 \n\t"\      add %esi, %eax
"punpcklbw %%mm7, "#F"      \n\t"\      punpcklbw %mm7, %mm0
"psubw "#B", %%mm6          \n\t"\      psubw %mm2, %mm6
"psraw $1, "#B"             \n\t"\      psraw $1, %mm2
"psubw "#A", %%mm6          \n\t"\      psubw %mm1, %mm6
"paddw %4, %%mm6            \n\t"\      paddw (%edx), %mm6
"psraw $7, %%mm6            \n\t"\      psraw $7, %mm6
"packuswb %%mm6, %%mm6      \n\t"\      packuswb %mm6, %mm6
OP(%%mm6, (%1), A, d)            \      movd %mm6, (%ecx)
"add %3, %1                 \n\t"       add %esi, %ecx

Michael