[gcc r12-2907] i386: Fix ICE with V64QImode broadcast permutation with -mavx512f -mno-avx512bw

[Jakub Jelinek]

https://gcc.gnu.org/g:240f07805db27cfc746276039c5edccb4c031070

commit r12-2907-g240f07805db27cfc746276039c5edccb4c031070
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Sat Aug 14 11:44:46 2021 +0200

    i386: Fix ICE with V64QImode broadcast permutation with -mavx512f -mno-avx512bw
    
    The testcase shows another problem, for TARGET_AVX512BW we have a single insn
    doing broadcast from the first element, but don't have one for broadcast
    of 2nd+ element (so for d->perm[0] we must return false), but for
    TARGET_AVX512F && !TARGET_AVX512BW we don't even have support for that other
    broadcast.  V64QImode case was just added to the AVX2 cases which had
    gcc_assert (!TARGET_AVX2 || d->perm[0]);
    but for V64QImode we actually need
    gcc_assert (!TARGET_AVX512BW || d->perm[0]);
    
    2021-08-14  Jakub Jelinek  <jakub@redhat.com>
    
            PR target/101896
            * config/i386/i386-expand.c (expand_vec_perm_broadcast_1)
            <case E_V64QImode>: For this mode assert
            !TARGET_AVX512BW || d->perm[0] rather than !TARGET_AVX2 || d->perm[0].
    
            * gcc.target/i386/avx512f-pr101896.c: New test.

Diff:
---
 gcc/config/i386/i386-expand.c                    | 5 ++++-
 gcc/testsuite/gcc.target/i386/avx512f-pr101896.c | 5 +++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/gcc/config/i386/i386-expand.c b/gcc/config/i386/i386-expand.c
index a652b25f534..4d7349cfc7c 100644
--- a/gcc/config/i386/i386-expand.c
+++ b/gcc/config/i386/i386-expand.c
@@ -20474,7 +20474,6 @@ expand_vec_perm_broadcast_1 (struct expand_vec_perm_d *d)
       emit_move_insn (d->target, gen_lowpart (d->vmode, dest));
       return true;
 
-    case E_V64QImode:
     case E_V32QImode:
     case E_V16HImode:
     case E_V8SImode:
@@ -20484,6 +20483,10 @@ expand_vec_perm_broadcast_1 (struct expand_vec_perm_d *d)
       gcc_assert (!TARGET_AVX2 || d->perm[0]);
       return false;
 
+    case E_V64QImode:
+      gcc_assert (!TARGET_AVX512BW || d->perm[0]);
+      return false;
+
     case E_V32HImode:
       gcc_assert (!TARGET_AVX512BW);
       return false;
diff --git a/gcc/testsuite/gcc.target/i386/avx512f-pr101896.c b/gcc/testsuite/gcc.target/i386/avx512f-pr101896.c
new file mode 100644
index 00000000000..c1805cccac4
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/avx512f-pr101896.c
@@ -0,0 +1,5 @@
+/* PR target/101896 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -mavx512f -mno-avx512bw" } */
+
+#include "../../gcc.dg/torture/vshuf-v64qi.c"