[Bug target/107863] [10/11/12/13 Regression] ICE with unrecognizable insn when using -funsigned-char with some SSE/AVX builtins

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107863

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |10.5
            Summary|ICE with unrecognizable     |[10/11/12/13 Regression]
                   |insn when using             |ICE with unrecognizable
                   |-funsigned-char with some   |insn when using
                   |AVX builtins                |-funsigned-char with some
                   |                            |SSE/AVX builtins
      Known to work|                            |4.4.7
           Keywords|                            |ice-on-valid-code
      Known to fail|                            |4.5.3
   Last reconfirmed|                            |2022-11-24
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Reduced to just:
#include <immintrin.h>

__m128i f(__m128i a) {
   return _mm_insert_epi8(a, -1, 2);
}

This only requires -msse4.1 -funsigned-char to reproduce the ICE.

;; _4 = __builtin_ia32_vec_set_v16qi (_1, 255, 2);

(insn 7 6 8 (set (reg:QI 86)
        (const_int 255 [0xff])) "/app/example.cpp":4:11 -1
     (nil))

Without -funsigned-char:
;; _4 = __builtin_ia32_vec_set_v16qi (_1, -1, 2);

(insn 7 6 8 (set (reg:QI 86)
        (const_int -1 [0xffffffffffffffff])) "/app/example.cpp":4:11 -1
     (nil))


I suspect the issue is the definition of __builtin_ia32_vec_set_v16qi uses char
type rather than signed/unsigned char here ...