[llvm-bugs] [Bug 47550] New: Missed optimization for range check for negative numbers

[via llvm-bugs]

https://bugs.llvm.org/show_bug.cgi?id=47550

            Bug ID: 47550
           Summary: Missed optimization for range check for negative
                    numbers
           Product: libraries
           Version: trunk
          Hardware: PC
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: Scalar Optimizations
          Assignee: unassignedbugs at nondot.org
          Reporter: david.bolvansky at gmail.com
                CC: llvm-bugs at lists.llvm.org

bool rangecheck (int i, int x)
{
  return i > x && i < 0;
}



Clang:
rangecheck(int, int):                       # @rangecheck(int, int)
        cmp     edi, esi
        setg    cl
        test    edi, edi
        sets    al
        and     al, cl
        ret

GCC:
rangecheck(int, int):
        cmp     edi, esi
        setg    al
        shr     edi, 31
        and     eax, edi
        ret


https://godbolt.org/z/PPTP4o

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