[llvm-bugs] [Bug 46133] New: Failure to optimize compare and bitwise and with same operands properly (stuck at intermediate transformation)

[via llvm-bugs]

https://bugs.llvm.org/show_bug.cgi?id=46133

            Bug ID: 46133
           Summary: Failure to optimize compare and bitwise and with same
                    operands properly (stuck at intermediate
                    transformation)
           Product: libraries
           Version: trunk
          Hardware: PC
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: Scalar Optimizations
          Assignee: unassignedbugs at nondot.org
          Reporter: gabravier at gmail.com
                CC: llvm-bugs at lists.llvm.org

bool f(int x, int y)
{
    if ((unsigned)x >= y)
        return false;

    return (x & 1) == 0;
}

This can be optimized to `return ~x & ((unsigned)x < y);`, but is only
optimized to `return ((unsigned)x < y) & !(x & 1);`. Furthermore, `return
((unsigned)x < y) & !(x & 1);` by itself gets optimized to `return ~x &
((unsigned)x < y);`, so the code above should also get optimized to that.

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