PATCH: Enable Intel AES/CLMUL

[H.J. Lu]

On Fri, Apr 04, 2008 at 08:30:40AM +0200, Uros Bizjak wrote:
> On Thu, Apr 3, 2008 at 11:51 PM, H.J. Lu <hjl.tools@gmail.com> wrote:
> 
> >  +  /* Enable SSE 4.2 if AES or CLMUL is enabled.  */
> >  +  if ((x86_aes || x86_clmul)
> >  +      && !(ix86_isa_flags_explicit & OPTION_MASK_ISA_SSE4_2))
> >  +    {
> >  +      ix86_isa_flags |= OPTION_MASK_ISA_SSE4_2_SET;
> >  +      ix86_isa_flags_explicit |= OPTION_MASK_ISA_SSE4_2_SET;
> >  +    }
> >  +
> 
> Do we really want to enable all SSE builtins if only AES functionality
> is required? I think that -msse -maes is more appropriate, since -msse
> instructs the compiler to enable support for SSE registers and -maes
> enables special AES instructions that depend on SSE registers.
> Unfortunately, we don't have separate option to enable only SSE
> registers without SSE builtins, but IMO we can live with that. Similar
> situation is with -mclmul. At minimum, -msse -mclmul should be
> required, I see no reason to enable everything up to sse4_2 for this
> insn.

SSE doesn't support V2DI. You need at least SSE2.

I can change

{ OPTION_MASK_ISA_SSE4_2, CODE_FOR_aesimc, 0, IX86_BUILTIN_AESIMC128, UNKNOWN , 0 },

to

{ OPTION_MASK_ISA_SSE2, CODE_FOR_aesimc, 0, IX86_BUILTIN_AESIMC128, UNKNOWN , 0 },

> 
> >  +/* We need definitions from the SSE4, SSSE3, SSE3, SSE2 and SSE header
> >  +   files.  */
> >  +#include <smmintrin.h>
> >  +
> 
> Actually we only need __v2di and __m128i typedefs here. Perhaps we can
> copy these two definitions here, or we can define
> 
> typedef long long __m128a __attribute__ ((vector_size (16), __may_alias));
> 
> and rewrite these new intrinsics to use this type?

<wmmintrin.h> from icc 10.1 includes SSE4 intrinsic header file. If
<wmmintrin.h> from gcc doesn't support SSE4 intrinsics, it will be
incompatible with icc. I can image other companies may implement
AES/CLMUL. I think it should be handled similar to SSE4 intrinsics.
That is we put AES/CLMUL intrinsics in a common intrinsic header file
and 2 different options, one of them is -maes/-mclmul, will enale
them.  -maes/-mclmul will still imply SSE4.


H.J.