On Mon, May 23, 2022 at 9:16 AM Roger Sayle <ro...@nextmovesoftware.com> wrote:
>
>
> This patch is an alternate/supplementary fix to PR tree-optimization/105668
> that provides a vcond_mask_v1titi optab/define_expand to the i386 backend.
> An undocumented feature/bug of GCC's vectorization is that any target that
> provides a vec_cmpeq<mode><mode> has to also provide a matching
> vcond_mask<mode><mode>. This backend patch preserves the status quo,
> rather than fixes the underlying problem.
IIRC, I also hit this issue a while ago. I was under impression it was
fixed in the meantime, but looks I was wrong.
> One aspect of this clean-up is that ix86_expand_sse_movcc provides
> fallback implementations using pand/pandn/por that effectively make
> V2DImode and V1TImode vcond_mask available on any TARGET_SSE2, not
> just TARGET_SSE4_2. This allows a simplification as V2DI mode can
> be handled by using a VI_128 mode iterator instead of a VI124_128
> mode iterator, and instead this define_expand is effectively renamed
> to provide a V1TImode vcond_mask expander (as V1TI isn't in VI_128).
>
> This patch has been tested on x86_64-pc-linux-gnu with make bootstrap
> and make -k check, both with and without --target_board=unix{-m32} with
> no new failures. The new test case is identical to the middle-end patch,
> so if both patches are approved, this'll be committed only once.
> Ok for mainline?
OK.
Thanks,
Uros.
>
>
> 2022-05-23 Roger Sayle <ro...@nextmovesoftware.com>
>
> gcc/ChangeLog
> PR tree-optimization/105668
> * config/i386/i386-expand.cc (ix86_expand_sse_movcc): Support
> V1TImode, just like V2DImode.
> * config/i386/sse.md (vcond_mask_<mode>Msseintvecmodelower>):
> Use VI_128 mode iterator instead of VI124_128 to include V2DI.
> (vcond_mask_v2div2di): Delete.
> (vcond_mask_v1tiv1ti): New define_expand.
>
> gcc/testsuite/ChangeLog
> PR tree-optimization/105668
> * gcc.target/i386/pr105668.c: New test case.
>
>
> Roger
> --
>
