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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/110068] missing min detection
Date: Thu, 01 Jun 2023 03:49:09 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110068

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
here is another one:
```
unsigned
f5 (unsigned  x)
{
  bool t =3D x >=3D 1U<<(sizeof(x)*8-1);
  if (!t)
    ;
  else
    x =3D 1U<<(sizeof(x)*8-1);
  return x;
}
```

this time LLVM does not detect it either.

easy way to see that out is by using riscv and -march=3Drv32gc_zba_zbb_zbc_=
zbs.
You should get for all 5 functions:
        li      a5,-2147483648
        minu    a0,a0,a5
        ret

Or:
        lui     a1, 524288
        minu    a0, a0, a1
        ret

Both are execute the same in the end.=