[llvm-bugs] [Bug 132071] [RISC-V] Miscompile on rv64gcv with -O[23]

[LLVM Bugs via llvm-bugs]

Issue	132071
Summary	[RISC-V] Miscompile on rv64gcv with -O[23]
Labels	new issue
Assignees
Reporter	ewlu

    Testcase:
```c
short a[12];
short b[12];
long long al;
int f;
short m = 31554;
long long q[12];
int main() {
  for (int i = 0; i < 2; ++i)
    q[i] = 6;
  for (short i = 0; i < 12; i += m - 31553) {
    a[i] = q[i];
    b[i] = f > q[i];
  }
  for (int i = 0; i < 12; ++i)
    al += a[i];
  for (int i = 0; i < 2; ++i)
    al += b[i];
  __builtin_printf("%llu\n", al);
}
```

Commands:
```
# riscv
$ ./bin/clang -march=rv64gcv_zvl256b -flto -O2 red.c -o user-config.out
$ QEMU_CPU=rv64,vlen=256,rvv_ta_all_1s=true,rvv_ma_all_1s=true,v=true,vext_spec=v1.0,zve32f=true,zve64f=true timeout --verbose -k 0.1 4 ./bin/qemu-riscv64 user-config.out 1
10

$ ./bin/clang -march=rv64gcv_zvl256b -flto -O3 red.c -o user-config.out
$ QEMU_CPU=rv64,vlen=256,rvv_ta_all_1s=true,rvv_ma_all_1s=true,v=true,vext_spec=v1.0,zve32f=true,zve64f=true timeout --verbose -k 0.1 4 ./bin/qemu-riscv64 user-config.out 1
10

# x86
$ ./native.out 1
12
```

Godbolt: https://godbolt.org/z/7hMW6eerT

Bisected to 9b7282e545d5e47315e3ffb9e5e00d0fb547c8e3 as the first bad commit

Found via fuzzer

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