[Bug target/97506] [11 Regression] ICE: in extract_insn, at recog.c:2294 (unrecognizable insn) with -mavx512vbmi -mavx512vl

[crazylht at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97506

Hongtao.liu <crazylht at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |crazylht at gmail dot com

--- Comment #2 from Hongtao.liu <crazylht at gmail dot com> ---
Could be fixed by

diff --git a/gcc/config/i386/i386-expand.c b/gcc/config/i386/i386-expand.c
index e6f8b314f18..19c12df4401 100644
--- a/gcc/config/i386/i386-expand.c
+++ b/gcc/config/i386/i386-expand.c
@@ -3525,6 +3525,14 @@ ix86_expand_sse_movcc (rtx dest, rtx cmp, rtx op_true,
rtx op_false)
   machine_mode mode = GET_MODE (dest);
   machine_mode cmpmode = GET_MODE (cmp);

+  /* Simplify this trivial compare, avoid ICE error in pr97506.  */
+  if (rtx_equal_p (op_true, op_false))
+    {
+      emit_move_insn (dest, op_true);
+      return;
+    }
+
   /* In AVX512F the result of comparison is an integer mask.  */
   bool maskcmp = mode != cmpmode && ix86_valid_mask_cmp_mode (mode);

But shouldn't middle end also simplify such trivial VCOND_EXPR.

  _4 = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
  _6 = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
  _8 = .VCONDU (_6, { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, _4, {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, 113);