Re: GCC 4.0.0 fsincos?

[Uros Bizjak]

Hello!
If I compile with
$ ~/usr/bin/gcc-4.0.0 -S Com_Code.cc -ffast-math -O2
the relevant generated code section is
#APP
        fldln2; fxch; fyl2x
#NO_APP
        fmulp   %st, %st(2)
        fxch    %st(1)
#APP
        fsqrt
#NO_APP
        fld     %st(1)
#APP
        fsin
#NO_APP
        fxch    %st(2)
#APP
        fcos
#NO_APP
So after generating R, a separate fsin and fcos seem to be generated. Am I
missing an option or something?
You should use -ffast-math together with -D__NO_MATH_INLINES in your 
compile flags, or use a newer glibc. -D__NO_MATH_INLINES should also be 
used for -mfpmath=sse to prevent generation of x87 instructions from 
mathinline.h header when SSE code is used for FP math operators. 
Otherwise  xmm reg->mem->x87 reg moves will kill your performance.

Uros.
Uros.