[PATCH 1/N] x86_64 vectorization support: vectorized math functions addition to Glibc

[Andi Kleen]

Rich Felker <dalias@libc.org> writes:
>
> This really seems like something the compiler should be doing --
> translating parallelizable calls to the standard math functions into
> calls to special simd versions (

Of course gcc already supports that. Even in two different flavours.

Not sure why the patch doesn't implement one of those ABIs though.

     -mveclibabi=type
           Specifies the ABI type to use for vectorizing intrinsics
           using an external library.
           Supported values for type are svml for the Intel short vector
           math library and acml for
           the AMD math core library.  To use this option, both
           -ftree-vectorize and
           -funsafe-math-optimizations have to be enabled, and an SVML
           or ACML ABI-compatible
           library must be specified at link time.

           GCC currently emits calls to "vmldExp2", "vmldLn2",
           "vmldLog102", "vmldLog102",
           "vmldPow2", "vmldTanh2", "vmldTan2", "vmldAtan2",
           "vmldAtanh2", "vmldCbrt2",
           "vmldSinh2", "vmldSin2", "vmldAsinh2", "vmldAsin2",
           "vmldCosh2", "vmldCos2",
           "vmldAcosh2", "vmldAcos2", "vmlsExp4", "vmlsLn4",
           "vmlsLog104", "vmlsLog104",
           "vmlsPow4", "vmlsTanh4", "vmlsTan4", "vmlsAtan4",
           "vmlsAtanh4", "vmlsCbrt4",
           "vmlsSinh4", "vmlsSin4", "vmlsAsinh4", "vmlsAsin4",
           "vmlsCosh4", "vmlsCos4",
           "vmlsAcosh4" and "vmlsAcos4" for corresponding function type
           when -mveclibabi=svml is
           used, and "__vrd2_sin", "__vrd2_cos", "__vrd2_exp",
           "__vrd2_log", "__vrd2_log2",
           "__vrd2_log10", "__vrs4_sinf", "__vrs4_cosf", "__vrs4_expf",
           "__vrs4_logf",
           "__vrs4_log2f", "__vrs4_log10f" and "__vrs4_powf" for the
           corresponding function type
           when -mveclibabi=acml is used.


-Andi


-- 
ak@linux.intel.com -- Speaking for myself only