[FFmpeg-devel] [RFC]Move is-align-a-power-of-two test up

[Måns Rullgård]

Carl Eugen Hoyos <cehoyos at rainbow.studorg.tuwien.ac.at> writes:

> Hi!
>
> FFmpeg compilation with icc's interprocedural optimization between
> files (-ipo) improves performance by 10% (h264) to 20% (theora).
> (Only tested with --enable-shared.)
> Unfortunately, it currently does not work out-of-the-box, because
> compilation with -ipo does not fail if an invalid value for .align is
> given ("linking" fails):
>
> $ cat align.c
> void foo(void){ __asm__ volatile(".align 3"); }
> $ icc align.c -c
> /tmp/iccgyMZFzas_.s: Assembler messages:
> /tmp/iccgyMZFzas_.s:13: Error: alignment not a power of 2
> $ icc align.c -c -ipo
> (succeeds and builds align.o)
> $ icc align.o
> ipo: remark #11001: performing single-file optimizations
> ipo: remark #11005: generating object file /tmp/ipo_iccWkeAyV.o
> /tmp/iccTgD2V5as_.s: Assembler messages:
> /tmp/iccTgD2V5as_.s:13: Error: alignment not a power of 2
> icc: error #10014: problem during multi-file optimization compilation
> (code 1)

Do you have any idea why this is so?

-- 
M?ns Rullg?rd
mans at mansr.com