[FFmpeg-devel] Patch: Inline asm fixes for Intel compiler on Windows

[Reimar Döffinger]

On 29.03.2014, at 18:12, "Ronald S. Bultje" <rsbultje at gmail.com> wrote:
> Hi,
> 
> On Sat, Mar 29, 2014 at 12:18 AM, Matt Oliver <protogonoi at gmail.com> wrote:
> 
>> OK here is a slightly different approach to fixing the missing CLTD
>> instruction support for icl inline asm. After looking into the situation
>> further I noticed that CLTD is only used in 2 places and in both places it
>> is for generating a sign mask.
> 
> 
> Why not create a macro that expands to the correct instruction supported
> for each compiler?
> 
> #if some stuff
> #define CLTD_CDQ "cdq"
> #else
> #define CLTD_CDQ "cltd"
> #endif
> 
> We do that for e.g. register size detection (e.g. REG_a for eax vs. rax), I
> think it's fine here also.

It's probably more the assembler used than the compiler actually.
Plus, we all seem to not have any of the affected systems at hand.
I admit I didn't expect we'd spend quite as much time on this.
Maybe we should indeed just switch it and figure out a solution if and when someone actually complains and we thus have a proper test-case?