1; RUN: opt < %s -instsimplify -S | FileCheck %s 2 3; fsub 0, (fsub 0, X) ==> X 4; CHECK-LABEL: @fsub_0_0_x( 5define float @fsub_0_0_x(float %a) { 6 %t1 = fsub float -0.0, %a 7 %ret = fsub float -0.0, %t1 8 9; CHECK: ret float %a 10 ret float %ret 11} 12 13; fsub X, 0 ==> X 14; CHECK-LABEL: @fsub_x_0( 15define float @fsub_x_0(float %a) { 16 %ret = fsub float %a, 0.0 17; CHECK: ret float %a 18 ret float %ret 19} 20 21; fadd X, -0 ==> X 22; CHECK-LABEL: @fadd_x_n0( 23define float @fadd_x_n0(float %a) { 24 %ret = fadd float %a, -0.0 25; CHECK: ret float %a 26 ret float %ret 27} 28 29; fmul X, 1.0 ==> X 30; CHECK-LABEL: @fmul_X_1( 31define double @fmul_X_1(double %a) { 32 %b = fmul double 1.000000e+00, %a ; <double> [#uses=1] 33 ; CHECK: ret double %a 34 ret double %b 35} 36 37; We can't optimize away the fadd in this test because the input 38; value to the function and subsequently to the fadd may be -0.0. 39; In that one special case, the result of the fadd should be +0.0 40; rather than the first parameter of the fadd. 41 42; Fragile test warning: We need 6 sqrt calls to trigger the bug 43; because the internal logic has a magic recursion limit of 6. 44; This is presented without any explanation or ability to customize. 45 46declare float @sqrtf(float) 47 48define float @PR22688(float %x) { 49 %1 = call float @sqrtf(float %x) 50 %2 = call float @sqrtf(float %1) 51 %3 = call float @sqrtf(float %2) 52 %4 = call float @sqrtf(float %3) 53 %5 = call float @sqrtf(float %4) 54 %6 = call float @sqrtf(float %5) 55 %7 = fadd float %6, 0.0 56 ret float %7 57 58; CHECK-LABEL: @PR22688( 59; CHECK: fadd float %6, 0.0 60} 61 62