[DAGCombiner] Add target hook function to decide folding (mul (add x, c1), c2)

[llvm-project.git] / llvm / test / Transforms / InstCombine / 2008-07-16-fsub.ll

; RUN: opt < %s -instcombine -S | grep sub
; PR2553

define double @test(double %X) nounwind {
        ; fsub of self can't be optimized away.
        %Y = fsub double %X, %X
        ret double %Y
}