; RUN: opt < %s -reassociate -constprop -instcombine -S | FileCheck %s define float @test1(float %A, float %B) { ; CHECK-LABEL: test1 ; CHECK-NEXT: %W = fadd float %B, 5.000000e+00 ; CHECK-NEXT: %X = fadd float %A, -7.000000e+00 ; CHECK-NEXT: %Y = fsub float %X, %W ; CHECK-NEXT: %Z = fadd float %Y, 1.200000e+01 ; CHECK-NEXT: ret float %Z %W = fadd float 5.0, %B %X = fadd float -7.0, %A %Y = fsub float %X, %W %Z = fadd float %Y, 12.0 ret float %Z } ; With sub reassociation, constant folding can eliminate all of the constants. define float @test2(float %A, float %B) { ; CHECK-LABEL: test2 ; CHECK-NEXT: %Z = fsub fast float %A, %B ; CHECK-NEXT: ret float %Z %W = fadd fast float %B, 5.000000e+00 %X = fadd fast float %A, -7.000000e+00 %Y = fsub fast float %X, %W %Z = fadd fast float %Y, 1.200000e+01 ret float %Z } define float @test3(float %A, float %B, float %C, float %D) { ; CHECK-LABEL: test3 ; CHECK-NEXT: %M = fadd float %A, 1.200000e+01 ; CHECK-NEXT: %N = fadd float %M, %B ; CHECK-NEXT: %O = fadd float %N, %C ; CHECK-NEXT: %P = fsub float %D, %O ; CHECK-NEXT: %Q = fadd float %P, 1.200000e+01 ; CHECK-NEXT: ret float %Q %M = fadd float %A, 1.200000e+01 %N = fadd float %M, %B %O = fadd float %N, %C %P = fsub float %D, %O %Q = fadd float %P, 1.200000e+01 ret float %Q } ; With sub reassociation, constant folding can eliminate the two 12 constants. define float @test4(float %A, float %B, float %C, float %D) { ; CHECK-LABEL: test4 ; CHECK-NEXT: %B.neg = fsub fast float -0.000000e+00, %B ; CHECK-NEXT: %O.neg = fsub fast float %B.neg, %A ; CHECK-NEXT: %P = fsub fast float %O.neg, %C ; CHECK-NEXT: %Q = fadd fast float %P, %D ; CHECK-NEXT: ret float %Q ; FIXME: InstCombine should be able to get us to the following: ; %sum = fadd fast float %B, %A ; %sum1 = fadd fast float %sum, %C ; %Q = fsub fast float %D, %sum1 ; ret i32 %Q %M = fadd fast float 1.200000e+01, %A %N = fadd fast float %M, %B %O = fadd fast float %N, %C %P = fsub fast float %D, %O %Q = fadd fast float 1.200000e+01, %P ret float %Q }