[Bug middle-end/118140] New: [15 Regression] RISC-V: Miscompile with -march=rv64gcv_zvl256b -O3 since r15-3992-g698e0ec89bc

[patrick at rivosinc dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118140

            Bug ID: 118140
           Summary: [15 Regression] RISC-V: Miscompile with
                    -march=rv64gcv_zvl256b -O3 since r15-3992-g698e0ec89bc
           Product: gcc
           Version: 15.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: patrick at rivosinc dot com
  Target Milestone: ---

Program:
long long a;
_Bool d;
char e;
_Bool f[17];
_Bool f_3;
int main() {
  for (char g = 3; g < 16; g++) {
    d |= ({
      int h = f[g - 1] ? 2 : 0;
      int i = f[g - 1] ? f_3 : 0;
      h > i;
    });
    e += f[g + 1];
  }
  if (d != 0)
    return 1;
}

Commands:
/scratch/tc-testing/tc-compiler-fuzz-bisect/build-rv64gcv/bin/riscv64-unknown-linux-gnu-gcc
-march=rv64gcv_zvl256b -O3 test.c -o user-config.out -fsigned-char
-fno-strict-aliasing -fwrapv
QEMU_CPU=rv64,vlen=256,rvv_ta_all_1s=true,rvv_ma_all_1s=true,v=true,vext_spec=v1.0,zve32f=true,zve32x=true,zve64d=true,zve64f=true,zve64x=true
timeout --verbose -k 0.1 4
/scratch/tc-testing/tc-compiler-fuzz-trunk/build-gcv/bin/qemu-riscv64
user-config.out

Found via fuzzer

First bad commit: r15-3992-g698e0ec89bc