[Bug target/103396] New: [GCN][BUILD] ICE RTL check: access of elt 4 of vector with last elt 3 in move_callee_saved_registers, at config/gcn/gcn.c:2821

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103396

            Bug ID: 103396
           Summary: [GCN][BUILD] ICE RTL check: access of elt 4 of vector
                    with last elt 3 in move_callee_saved_registers, at
                    config/gcn/gcn.c:2821
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Keywords: build, ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: burnus at gcc dot gnu.org
                CC: ams at gcc dot gnu.org, rdapp at gcc dot gnu.org, sayle at 
gcc dot gnu.org
  Target Milestone: ---
              Host: x86_64-gnu-linux
            Target: amdgcn-amdhsa

Bisecting points at r12-5436-gdc915b361bbc99da83fc53db7f7e0e28d0ce12c8
Date:   Sun Nov 21 11:40:08 2021 +0000

    Tweak tree-ssa-math-opts.c to solve PR target/102117.
...
    2021-11-21  Roger Sayle  <ro...@nextmovesoftware.com>
                Robin Dapp  <rd...@linux.ibm.com>

    gcc/ChangeLog
            PR target/102117
            * tree-ssa-math-opts.c (convert_mult_to_widen): Recognize
            signed WIDEN_MULT_EXPR if the target supports umul_widen_optab.
...

Compiling libgfortran/runtime/environ.c during bootstrap with -march=gfx900 -O2
fails with:

during RTL pass: pro_and_epilogue

libgfortran/runtime/environ.c: In function 'search_unit':
libgfortran/runtime/environ.c:319:1: internal compiler error: RTL check: access
of elt 4 of vector with last elt 3 in move_callee_saved_registers, at
config/gcn/gcn.c:2821
  319 | }
      | ^
0x908087 rtvec_check_failed_bounds(rtvec_def const*, int, char const*, int,
char const*)
        gcc-mainline/gcc/rtl.c:975
0x9aa041 move_callee_saved_registers
        gcc-mainline/gcc/config/gcn/gcn.c:2821
0x14679cf gcn_expand_prologue()
        gcc-mainline/gcc/config/gcn/gcn.c:2939
0x17d331a gen_prologue()
        gcc-mainline/gcc/config/gcn/gcn.md:714
0x1460758 target_gen_prologue
        ./insn-target-def.h:433
0xdb3537 make_prologue_seq
        gcc-mainline/gcc/function.c:5823
0xdb36c2 thread_prologue_and_epilogue_insns()