; Transforms/InstCombine/fcmp-select.ll define double @test_fcmp_select_maxnum(double %x) { %cmp1 = fcmp ogt double %x, 1.000000 %sel1 = select nnan nsz i1 %cmp1, double %x, double 1.000000 %cmp2 = fcmp olt double %sel1, 255.000000 %sel2 = select nnan nsz i1 %cmp2, double %sel1, double 255.000000 ret double %sel2 } => define double @test_fcmp_select_maxnum(double %x) { %sel1 = fmax nsz double %x, 1.000000 %sel2 = fmin nsz double %sel1, 255.000000 ret double %sel2 } Transformation doesn't verify! (unsound) ERROR: Value mismatch Example: double %x = #x7ff4000000000000 (SNaN) Source: i1 %cmp1 = #x0 (0) double %sel1 = #x3ff0000000000000 (1) i1 %cmp2 = #x1 (1) double %sel2 = #x3ff0000000000000 (1) Target: double %sel1 = #x7ffc000000000000 (QNaN) double %sel2 = #x406fe00000000000 (255) Source value: #x3ff0000000000000 (1) Target value: #x406fe00000000000 (255)