Hello Jakub!
> On 13 Feb 2018, at 00:59, Jakub Jelinek <ja...@redhat.com> wrote:
>
> Hi!
>
> The following testcase ICEs, because the expander is called with
> a subreg as operands[2], and gen_lowpart on it creates another subreg
> from the same pseudo; the instructions rely on match_dup working:
> (define_insn "*<avx512>_vpermi2var<mode>3_mask"
> [(set (match_operand:VF_AVX512VL 0 "register_operand" "=v")
> (vec_merge:VF_AVX512VL
> (unspec:VF_AVX512VL
> [(match_operand:<sseintvecmode> 2 "register_operand" "0")
> (match_operand:VF_AVX512VL 1 "register_operand" "v")
> (match_operand:VF_AVX512VL 3 "nonimmediate_operand" "vm")]
> UNSPEC_VPERMT2)
> (subreg:VF_AVX512VL (match_dup 2) 0)
> (match_operand:<avx512fmaskmode> 4 "register_operand" "Yk")))]
> and this only works if operands[2] is initially a REG.
>
> Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for
> trunk?
Patch is OK for trunk.
—
Thanks, K
>
> 2018-02-12 Jakub Jelinek <ja...@redhat.com>
>
> PR target/84336
> * config/i386/sse.md (<avx512>_vpermi2var<mode>3_mask): Force
> operands[2] into a REG before using gen_lowpart on it.
>
> * gcc.target/i386/pr84336.c: New test.
>
> --- gcc/config/i386/sse.md.jj 2018-02-06 13:13:03.911758746 +0100
> +++ gcc/config/i386/sse.md 2018-02-12 18:55:27.257386614 +0100
> @@ -18183,7 +18183,10 @@ (define_expand "<avx512>_vpermi2var<mode
> (match_dup 5)
> (match_operand:<avx512fmaskmode> 4 "register_operand")))]
> "TARGET_AVX512F"
> - "operands[5] = gen_lowpart (<MODE>mode, operands[2]);")
> +{
> + operands[2] = force_reg (<sseintvecmode>mode, operands[2]);
> + operands[5] = gen_lowpart (<MODE>mode, operands[2]);
> +})
>
> (define_insn "*<avx512>_vpermi2var<mode>3_mask"
> [(set (match_operand:VPERMI2I 0 "register_operand" "=v")
> --- gcc/testsuite/gcc.target/i386/pr84336.c.jj 2018-02-12
> 19:10:15.861401288 +0100
> +++ gcc/testsuite/gcc.target/i386/pr84336.c 2018-02-12 19:09:17.911405540
> +0100
> @@ -0,0 +1,13 @@
> +/* PR target/84336 */
> +/* { dg-do compile } */
> +/* { dg-options "-O0 -ftree-ter -mavx512f" } */
> +
> +#include <x86intrin.h>
> +
> +struct S { __m512i h; } b;
> +
> +__m512
> +foo (__m512 a, __mmask16 c, __m512 d)
> +{
> + return _mm512_mask2_permutex2var_ps (a, b.h, c, d);
> +}
>
> Jakub
