[Bug tree-optimization/96714] New: Failure to optimize sqrt*sqrt of same variable with ffast-math

[gabravier at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96714

            Bug ID: 96714
           Summary: Failure to optimize sqrt*sqrt of same variable with
                    ffast-math
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gabravier at gmail dot com
  Target Milestone: ---

float f(float x)
{
    return __builtin_sqrtf(x) * __builtin_sqrtf(x);
}

This can be optimized to `return x;` (with fast math enabled). This
transformation is done by LLVM, but not by GCC.