[FFmpeg-devel] PATCH: av_strtod

Reimar Döffinger Reimar.Doeffinger
Tue Jun 2 09:55:04 CEST 2009

On Mon, Jun 01, 2009 at 10:59:06PM -0400, Pavel Pavlov wrote:
> prone and alow 30 inputs instead of 10. One more issue - all 64 bit
> constants had to be changed into arrays, so that there would never be
> any standalone 64-bit static value as input to asm block; otherwise
> compiler tries to optimize it and use that 64 bit value as immidiate val
> and produces complete junk that runs like 3-4 time slower.
> Instead of 
> 	movq _some64bit_const, mmx_reg //_some64bit_const is {0x1234,
> 0x5678}
> It would emit junk like 
> 	push 0x1234
> 	push 0x5678
> 	movq esp, mmx_reg 

Well, I think you now know one of the reasons why MANGLE is used instead
of "m" constraints: because every single constraint is one thing that
the compiler can mess up, and from experience at least one compiler
version will mess it up.
So far MANGLE has been far more maintainable, are you really sure you
can't use it? Because even the Solaris compiler manages to handle it.

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