[FFmpeg-devel] [PATCH] SSE RDFT

[Måns Rullgård]

Jason Garrett-Glaser <darkshikari at gmail.com> writes:

> 2010/6/24 M?ns Rullg?rd <mans at mansr.com>:
>> Jason Garrett-Glaser <darkshikari at gmail.com> writes:
>>
>>> 2010/6/24 M?ns Rullg?rd <mans at mansr.com>:
>>>> Michael Niedermayer <michaelni at gmx.at> writes:
>>>>
>>>>> btw, speaking of yasm, a not too long while ago i realized that configure
>>>>> simply compiles without yasm optimizations if yasm isnt installed
>>>>> i noticed it just because x264 doesnt and warns, we should do the same
>>>>> this issue alone weighs heavier than any difference between inline and
>>>>> yasm. Because loosing the optimizations without the user knowing is really
>>>>> bad.
>>>>
>>>> Done.
>>>
>>> This is not sufficient. ?From years of experience with x264, people
>>> will NEVER NOTICE the configure warning, and will proceed to compile
>>> obliviously. ?They will then complain incessantly about slow it is.
>>>
>>> This is doubly important with more and more of ffmpeg's asm being in
>>> yasm -- particularly the upcoming VP8 decoder, where we are going to
>>> market ourselves on speed.
>>>
>>> I suggest that configure fail with an error (telling the user to
>>> install yasm or disable asm) if the following conditions are true:
>>>
>>> 1) architecture is x86 or x86_64
>>> 2) --disable-mmx is not set
>>> 3) --disable-yasm is not set
>>
>> Sounds good to me. ?All in favour?
>
> Seems there's no objections, let's do it?

I suggest this patch then:

diff --git a/configure b/configure
index c2690db..ac574bb 100755
--- a/configure
+++ b/configure
@@ -2410,9 +2410,9 @@ EOF
     case "$objformat" in
         elf) enabled debug && append YASMFLAGS "-g dwarf2" ;;
     esac
-    if ! disabled yasm; then
+    if ! disabled_any mmx yasm; then
         check_yasm "pabsw xmm0, xmm0" && enable yasm ||
-            warn "yasm not found, performance will suffer"
+            die "yasm not found, use --disable-yasm for a crippled build"
     fi
 
     case "$cpu" in

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