; NOTE: Assertions have been autogenerated by utils/update_test_checks.py ; ; Test numbering remains continuous across: ; - InstCombine/fast-basictest.ll ; - PhaseOrdering/fast-basictest.ll ; - PhaseOrdering/fast-reassociate-gvn.ll ; - Reassociate/fast-basictest.ll ; ; RUN: opt < %s -instcombine -S | FileCheck %s ; With reassociation, constant folding can eliminate the 12 and -12 constants. define float @test1(float %arg) { ; CHECK-LABEL: @test1( ; CHECK-NEXT: [[TMP1:%.*]] = fneg fast float [[ARG:%.*]] ; CHECK-NEXT: ret float [[TMP1]] ; %t1 = fsub fast float -1.200000e+01, %arg %t2 = fadd fast float %t1, 1.200000e+01 ret float %t2 } ; Check again using the minimal subset of FMF. ; Both 'reassoc' and 'nsz' are required. define float @test1_minimal(float %arg) { ; CHECK-LABEL: @test1_minimal( ; CHECK-NEXT: [[TMP1:%.*]] = fneg reassoc nsz float [[ARG:%.*]] ; CHECK-NEXT: ret float [[TMP1]] ; %t1 = fsub reassoc nsz float -1.200000e+01, %arg %t2 = fadd reassoc nsz float %t1, 1.200000e+01 ret float %t2 } ; Verify the fold is not done with only 'reassoc' ('nsz' is required). define float @test1_reassoc(float %arg) { ; CHECK-LABEL: @test1_reassoc( ; CHECK-NEXT: [[T1:%.*]] = fsub reassoc float -1.200000e+01, [[ARG:%.*]] ; CHECK-NEXT: [[T2:%.*]] = fadd reassoc float [[T1]], 1.200000e+01 ; CHECK-NEXT: ret float [[T2]] ; %t1 = fsub reassoc float -1.200000e+01, %arg %t2 = fadd reassoc float %t1, 1.200000e+01 ret float %t2 } ; ((a + (-3)) + b) + 3 -> a + b ; That only works with both instcombine and reassociate passes enabled. ; Check that instcombine is not enough. define float @test2(float %reg109, float %reg1111) { ; CHECK-LABEL: @test2( ; CHECK-NEXT: [[REG115:%.*]] = fadd fast float [[REG109:%.*]], -3.000000e+01 ; CHECK-NEXT: [[REG116:%.*]] = fadd fast float [[REG115]], [[REG1111:%.*]] ; CHECK-NEXT: [[REG117:%.*]] = fadd fast float [[REG116]], 3.000000e+01 ; CHECK-NEXT: ret float [[REG117]] ; %reg115 = fadd fast float %reg109, -3.000000e+01 %reg116 = fadd fast float %reg115, %reg1111 %reg117 = fadd fast float %reg116, 3.000000e+01 ret float %reg117 } define float @test2_no_FMF(float %reg109, float %reg1111) { ; CHECK-LABEL: @test2_no_FMF( ; CHECK-NEXT: [[REG115:%.*]] = fadd float [[REG109:%.*]], -3.000000e+01 ; CHECK-NEXT: [[REG116:%.*]] = fadd float [[REG115]], [[REG1111:%.*]] ; CHECK-NEXT: [[REG117:%.*]] = fadd float [[REG116]], 3.000000e+01 ; CHECK-NEXT: ret float [[REG117]] ; %reg115 = fadd float %reg109, -3.000000e+01 %reg116 = fadd float %reg115, %reg1111 %reg117 = fadd float %reg116, 3.000000e+01 ret float %reg117 } define float @test2_reassoc(float %reg109, float %reg1111) { ; CHECK-LABEL: @test2_reassoc( ; CHECK-NEXT: [[REG115:%.*]] = fadd reassoc float [[REG109:%.*]], -3.000000e+01 ; CHECK-NEXT: [[REG116:%.*]] = fadd reassoc float [[REG115]], [[REG1111:%.*]] ; CHECK-NEXT: [[REG117:%.*]] = fadd reassoc float [[REG116]], 3.000000e+01 ; CHECK-NEXT: ret float [[REG117]] ; %reg115 = fadd reassoc float %reg109, -3.000000e+01 %reg116 = fadd reassoc float %reg115, %reg1111 %reg117 = fadd reassoc float %reg116, 3.000000e+01 ret float %reg117 } ; (-X)*Y + Z -> Z-X*Y define float @test7(float %X, float %Y, float %Z) { ; CHECK-LABEL: @test7( ; CHECK-NEXT: [[TMP1:%.*]] = fmul fast float [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: [[C:%.*]] = fsub fast float [[Z:%.*]], [[TMP1]] ; CHECK-NEXT: ret float [[C]] ; %A = fsub fast float 0.0, %X %B = fmul fast float %A, %Y %C = fadd fast float %B, %Z ret float %C } define float @test7_unary_fneg(float %X, float %Y, float %Z) { ; CHECK-LABEL: @test7_unary_fneg( ; CHECK-NEXT: [[TMP1:%.*]] = fmul fast float [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: [[C:%.*]] = fsub fast float [[Z:%.*]], [[TMP1]] ; CHECK-NEXT: ret float [[C]] ; %A = fneg fast float %X %B = fmul fast float %A, %Y %C = fadd fast float %B, %Z ret float %C } define float @test7_reassoc_nsz(float %X, float %Y, float %Z) { ; CHECK-LABEL: @test7_reassoc_nsz( ; CHECK-NEXT: [[TMP1:%.*]] = fmul reassoc nsz float [[X:%.*]], [[Y:%.*]] ; CHECK-NEXT: [[C:%.*]] = fsub reassoc nsz float [[Z:%.*]], [[TMP1]] ; CHECK-NEXT: ret float [[C]] ; %A = fsub reassoc nsz float 0.0, %X %B = fmul reassoc nsz float %A, %Y %C = fadd reassoc nsz float %B, %Z ret float %C } ; Verify that fold is not done only with 'reassoc' ('nsz' is required) define float @test7_reassoc(float %X, float %Y, float %Z) { ; CHECK-LABEL: @test7_reassoc( ; CHECK-NEXT: [[A:%.*]] = fsub reassoc float 0.000000e+00, [[X:%.*]] ; CHECK-NEXT: [[B:%.*]] = fmul reassoc float [[A]], [[Y:%.*]] ; CHECK-NEXT: [[C:%.*]] = fadd reassoc float [[B]], [[Z:%.*]] ; CHECK-NEXT: ret float [[C]] ; %A = fsub reassoc float 0.0, %X %B = fmul reassoc float %A, %Y %C = fadd reassoc float %B, %Z ret float %C } define float @test8(float %X) { ; CHECK-LABEL: @test8( ; CHECK-NEXT: [[TMP1:%.*]] = fmul fast float [[X:%.*]], 9.400000e+01 ; CHECK-NEXT: ret float [[TMP1]] ; %Y = fmul fast float %X, 4.700000e+01 %Z = fadd fast float %Y, %Y ret float %Z } ; Check again with 'reassoc' and 'nsz' ('nsz' not technically required). define float @test8_reassoc_nsz(float %X) { ; CHECK-LABEL: @test8_reassoc_nsz( ; CHECK-NEXT: [[TMP1:%.*]] = fmul reassoc nsz float [[X:%.*]], 9.400000e+01 ; CHECK-NEXT: ret float [[TMP1]] ; %Y = fmul reassoc nsz float %X, 4.700000e+01 %Z = fadd reassoc nsz float %Y, %Y ret float %Z } ; TODO: This doesn't require 'nsz'. It should fold to X * 94.0 define float @test8_reassoc(float %X) { ; CHECK-LABEL: @test8_reassoc( ; CHECK-NEXT: [[Y:%.*]] = fmul reassoc float [[X:%.*]], 4.700000e+01 ; CHECK-NEXT: [[Z:%.*]] = fadd reassoc float [[Y]], [[Y]] ; CHECK-NEXT: ret float [[Z]] ; %Y = fmul reassoc float %X, 4.700000e+01 %Z = fadd reassoc float %Y, %Y ret float %Z } ; Side note: (x + x + x) and (3*x) each have only a single rounding. So ; transforming x+x+x to 3*x is always safe, even without any FMF. ; To avoid that special-case, we have the addition of 'x' four times, here. define float @test9(float %X) { ; CHECK-LABEL: @test9( ; CHECK-NEXT: [[TMP1:%.*]] = fmul fast float [[X:%.*]], 4.000000e+00 ; CHECK-NEXT: ret float [[TMP1]] ; %Y = fadd fast float %X ,%X %Z = fadd fast float %Y, %X %W = fadd fast float %Z, %X ret float %W } ; Check again with 'reassoc' and 'nsz' ('nsz' not technically required). define float @test9_reassoc_nsz(float %X) { ; CHECK-LABEL: @test9_reassoc_nsz( ; CHECK-NEXT: [[TMP1:%.*]] = fmul reassoc nsz float [[X:%.*]], 4.000000e+00 ; CHECK-NEXT: ret float [[TMP1]] ; %Y = fadd reassoc nsz float %X ,%X %Z = fadd reassoc nsz float %Y, %X %W = fadd reassoc nsz float %Z, %X ret float %W } ; TODO: This doesn't require 'nsz'. It should fold to 4 * x define float @test9_reassoc(float %X) { ; CHECK-LABEL: @test9_reassoc( ; CHECK-NEXT: [[Y:%.*]] = fadd reassoc float [[X:%.*]], [[X]] ; CHECK-NEXT: [[Z:%.*]] = fadd reassoc float [[Y]], [[X]] ; CHECK-NEXT: [[W:%.*]] = fadd reassoc float [[Z]], [[X]] ; CHECK-NEXT: ret float [[W]] ; %Y = fadd reassoc float %X ,%X %Z = fadd reassoc float %Y, %X %W = fadd reassoc float %Z, %X ret float %W } define float @test10(float %W) { ; CHECK-LABEL: @test10( ; CHECK-NEXT: [[Z:%.*]] = fmul fast float [[W:%.*]], 3.810000e+02 ; CHECK-NEXT: ret float [[Z]] ; %X = fmul fast float %W, 127.0 %Y = fadd fast float %X ,%X %Z = fadd fast float %Y, %X ret float %Z } ; Check again using the minimal subset of FMF. ; Check again with 'reassoc' and 'nsz' ('nsz' not technically required). define float @test10_reassoc_nsz(float %W) { ; CHECK-LABEL: @test10_reassoc_nsz( ; CHECK-NEXT: [[Z:%.*]] = fmul reassoc nsz float [[W:%.*]], 3.810000e+02 ; CHECK-NEXT: ret float [[Z]] ; %X = fmul reassoc nsz float %W, 127.0 %Y = fadd reassoc nsz float %X ,%X %Z = fadd reassoc nsz float %Y, %X ret float %Z } ; TODO: This doesn't require 'nsz'. It should fold to W*381.0. define float @test10_reassoc(float %W) { ; CHECK-LABEL: @test10_reassoc( ; CHECK-NEXT: [[X:%.*]] = fmul reassoc float [[W:%.*]], 1.270000e+02 ; CHECK-NEXT: [[Y:%.*]] = fadd reassoc float [[X]], [[X]] ; CHECK-NEXT: [[Z:%.*]] = fadd reassoc float [[Y]], [[X]] ; CHECK-NEXT: ret float [[Z]] ; %X = fmul reassoc float %W, 127.0 %Y = fadd reassoc float %X ,%X %Z = fadd reassoc float %Y, %X ret float %Z } define float @test11(float %X) { ; CHECK-LABEL: @test11( ; CHECK-NEXT: [[TMP1:%.*]] = fmul fast float [[X:%.*]], 3.000000e+00 ; CHECK-NEXT: [[TMP2:%.*]] = fsub fast float 6.000000e+00, [[TMP1]] ; CHECK-NEXT: ret float [[TMP2]] ; %A = fsub fast float 1.000000e+00, %X %B = fsub fast float 2.000000e+00, %X %C = fsub fast float 3.000000e+00, %X %Y = fadd fast float %A ,%B %Z = fadd fast float %Y, %C ret float %Z } ; Check again with 'reassoc' and 'nsz' ('nsz' not technically required). define float @test11_reassoc_nsz(float %X) { ; CHECK-LABEL: @test11_reassoc_nsz( ; CHECK-NEXT: [[TMP1:%.*]] = fmul reassoc nsz float [[X:%.*]], 3.000000e+00 ; CHECK-NEXT: [[TMP2:%.*]] = fsub reassoc nsz float 6.000000e+00, [[TMP1]] ; CHECK-NEXT: ret float [[TMP2]] ; %A = fsub reassoc nsz float 1.000000e+00, %X %B = fsub reassoc nsz float 2.000000e+00, %X %C = fsub reassoc nsz float 3.000000e+00, %X %Y = fadd reassoc nsz float %A ,%B %Z = fadd reassoc nsz float %Y, %C ret float %Z } ; TODO: This doesn't require 'nsz'. It should fold to (6.0 - 3.0*x) define float @test11_reassoc(float %X) { ; CHECK-LABEL: @test11_reassoc( ; CHECK-NEXT: [[A:%.*]] = fsub reassoc float 1.000000e+00, [[X:%.*]] ; CHECK-NEXT: [[B:%.*]] = fsub reassoc float 2.000000e+00, [[X]] ; CHECK-NEXT: [[C:%.*]] = fsub reassoc float 3.000000e+00, [[X]] ; CHECK-NEXT: [[Y:%.*]] = fadd reassoc float [[A]], [[B]] ; CHECK-NEXT: [[Z:%.*]] = fadd reassoc float [[Y]], [[C]] ; CHECK-NEXT: ret float [[Z]] ; %A = fsub reassoc float 1.000000e+00, %X %B = fsub reassoc float 2.000000e+00, %X %C = fsub reassoc float 3.000000e+00, %X %Y = fadd reassoc float %A ,%B %Z = fadd reassoc float %Y, %C ret float %Z } define float @test12(float %X1, float %X2, float %X3) { ; CHECK-LABEL: @test12( ; CHECK-NEXT: [[TMP1:%.*]] = fsub fast float [[X3:%.*]], [[X2:%.*]] ; CHECK-NEXT: [[D:%.*]] = fmul fast float [[TMP1]], [[X1:%.*]] ; CHECK-NEXT: ret float [[D]] ; %A = fsub fast float 0.000000e+00, %X1 %B = fmul fast float %A, %X2 ; -X1*X2 %C = fmul fast float %X1, %X3 ; X1*X3 %D = fadd fast float %B, %C ; -X1*X2 + X1*X3 -> X1*(X3-X2) ret float %D } define float @test12_unary_fneg(float %X1, float %X2, float %X3) { ; CHECK-LABEL: @test12_unary_fneg( ; CHECK-NEXT: [[TMP1:%.*]] = fsub fast float [[X3:%.*]], [[X2:%.*]] ; CHECK-NEXT: [[D:%.*]] = fmul fast float [[TMP1]], [[X1:%.*]] ; CHECK-NEXT: ret float [[D]] ; %A = fneg fast float %X1 %B = fmul fast float %A, %X2 ; -X1*X2 %C = fmul fast float %X1, %X3 ; X1*X3 %D = fadd fast float %B, %C ; -X1*X2 + X1*X3 -> X1*(X3-X2) ret float %D } define float @test12_reassoc_nsz(float %X1, float %X2, float %X3) { ; CHECK-LABEL: @test12_reassoc_nsz( ; CHECK-NEXT: [[TMP1:%.*]] = fsub reassoc nsz float [[X3:%.*]], [[X2:%.*]] ; CHECK-NEXT: [[D:%.*]] = fmul reassoc nsz float [[TMP1]], [[X1:%.*]] ; CHECK-NEXT: ret float [[D]] ; %A = fsub reassoc nsz float 0.000000e+00, %X1 %B = fmul reassoc nsz float %A, %X2 ; -X1*X2 %C = fmul reassoc nsz float %X1, %X3 ; X1*X3 %D = fadd reassoc nsz float %B, %C ; -X1*X2 + X1*X3 -> X1*(X3-X2) ret float %D } ; TODO: check if 'nsz' is technically required. Currently the optimization ; is not done with only 'reassoc' without 'nsz'. define float @test12_reassoc(float %X1, float %X2, float %X3) { ; CHECK-LABEL: @test12_reassoc( ; CHECK-NEXT: [[A:%.*]] = fsub reassoc float 0.000000e+00, [[X1:%.*]] ; CHECK-NEXT: [[B:%.*]] = fmul reassoc float [[A]], [[X2:%.*]] ; CHECK-NEXT: [[C:%.*]] = fmul reassoc float [[X1]], [[X3:%.*]] ; CHECK-NEXT: [[D:%.*]] = fadd reassoc float [[B]], [[C]] ; CHECK-NEXT: ret float [[D]] ; %A = fsub reassoc float 0.000000e+00, %X1 %B = fmul reassoc float %A, %X2 ; -X1*X2 %C = fmul reassoc float %X1, %X3 ; X1*X3 %D = fadd reassoc float %B, %C ; -X1*X2 + X1*X3 -> X1*(X3-X2) ret float %D } ; (x1 * 47) + (x2 * -47) => (x1 - x2) * 47 ; That only works with both instcombine and reassociate passes enabled. ; Check that instcombine is not enough. define float @test13(float %X1, float %X2) { ; CHECK-LABEL: @test13( ; CHECK-NEXT: [[B:%.*]] = fmul fast float [[X1:%.*]], 4.700000e+01 ; CHECK-NEXT: [[C:%.*]] = fmul fast float [[X2:%.*]], -4.700000e+01 ; CHECK-NEXT: [[D:%.*]] = fadd fast float [[B]], [[C]] ; CHECK-NEXT: ret float [[D]] ; %B = fmul fast float %X1, 47. ; X1*47 %C = fmul fast float %X2, -47. ; X2*-47 %D = fadd fast float %B, %C ; X1*47 + X2*-47 -> 47*(X1-X2) ret float %D } define float @test13_reassoc_nsz(float %X1, float %X2) { ; CHECK-LABEL: @test13_reassoc_nsz( ; CHECK-NEXT: [[B:%.*]] = fmul reassoc nsz float [[X1:%.*]], 4.700000e+01 ; CHECK-NEXT: [[C:%.*]] = fmul reassoc nsz float [[X2:%.*]], -4.700000e+01 ; CHECK-NEXT: [[D:%.*]] = fadd reassoc nsz float [[B]], [[C]] ; CHECK-NEXT: ret float [[D]] ; %B = fmul reassoc nsz float %X1, 47. ; X1*47 %C = fmul reassoc nsz float %X2, -47. ; X2*-47 %D = fadd reassoc nsz float %B, %C ; X1*47 + X2*-47 -> 47*(X1-X2) ret float %D } define float @test13_reassoc(float %X1, float %X2) { ; CHECK-LABEL: @test13_reassoc( ; CHECK-NEXT: [[B:%.*]] = fmul reassoc float [[X1:%.*]], 4.700000e+01 ; CHECK-NEXT: [[C:%.*]] = fmul reassoc float [[X2:%.*]], -4.700000e+01 ; CHECK-NEXT: [[D:%.*]] = fadd reassoc float [[B]], [[C]] ; CHECK-NEXT: ret float [[D]] ; %B = fmul reassoc float %X1, 47. ; X1*47 %C = fmul reassoc float %X2, -47. ; X2*-47 %D = fadd reassoc float %B, %C ; X1*47 + X2*-47 -> 47*(X1-X2) ret float %D } define float @test14(float %arg) { ; CHECK-LABEL: @test14( ; CHECK-NEXT: [[T2:%.*]] = fmul fast float [[ARG:%.*]], 1.440000e+02 ; CHECK-NEXT: ret float [[T2]] ; %t1 = fmul fast float 1.200000e+01, %arg %t2 = fmul fast float %t1, 1.200000e+01 ret float %t2 } define float @test14_reassoc(float %arg) { ; CHECK-LABEL: @test14_reassoc( ; CHECK-NEXT: [[T2:%.*]] = fmul reassoc float [[ARG:%.*]], 1.440000e+02 ; CHECK-NEXT: ret float [[T2]] ; %t1 = fmul reassoc float 1.200000e+01, %arg %t2 = fmul reassoc float %t1, 1.200000e+01 ret float %t2 } ; (b+(a+1234))+-a -> b+1234 ; That only works with both instcombine and reassociate passes enabled. ; Check that instcombine is not enough. define float @test15(float %b, float %a) { ; CHECK-LABEL: @test15( ; CHECK-NEXT: [[TMP1:%.*]] = fadd fast float [[A:%.*]], 1.234000e+03 ; CHECK-NEXT: [[TMP2:%.*]] = fadd fast float [[TMP1]], [[B:%.*]] ; CHECK-NEXT: [[TMP3:%.*]] = fsub fast float [[TMP2]], [[A]] ; CHECK-NEXT: ret float [[TMP3]] ; %1 = fadd fast float %a, 1234.0 %2 = fadd fast float %b, %1 %3 = fsub fast float 0.0, %a %4 = fadd fast float %2, %3 ret float %4 } define float @test15_unary_fneg(float %b, float %a) { ; CHECK-LABEL: @test15_unary_fneg( ; CHECK-NEXT: [[TMP1:%.*]] = fadd fast float [[A:%.*]], 1.234000e+03 ; CHECK-NEXT: [[TMP2:%.*]] = fadd fast float [[TMP1]], [[B:%.*]] ; CHECK-NEXT: [[TMP3:%.*]] = fsub fast float [[TMP2]], [[A]] ; CHECK-NEXT: ret float [[TMP3]] ; %1 = fadd fast float %a, 1234.0 %2 = fadd fast float %b, %1 %3 = fneg fast float %a %4 = fadd fast float %2, %3 ret float %4 } define float @test15_reassoc_nsz(float %b, float %a) { ; CHECK-LABEL: @test15_reassoc_nsz( ; CHECK-NEXT: [[TMP1:%.*]] = fadd reassoc nsz float [[A:%.*]], 1.234000e+03 ; CHECK-NEXT: [[TMP2:%.*]] = fadd reassoc nsz float [[TMP1]], [[B:%.*]] ; CHECK-NEXT: [[TMP3:%.*]] = fsub reassoc nsz float [[TMP2]], [[A]] ; CHECK-NEXT: ret float [[TMP3]] ; %1 = fadd reassoc nsz float %a, 1234.0 %2 = fadd reassoc nsz float %b, %1 %3 = fsub reassoc nsz float 0.0, %a %4 = fadd reassoc nsz float %2, %3 ret float %4 } define float @test15_reassoc(float %b, float %a) { ; CHECK-LABEL: @test15_reassoc( ; CHECK-NEXT: [[TMP1:%.*]] = fadd reassoc float [[A:%.*]], 1.234000e+03 ; CHECK-NEXT: [[TMP2:%.*]] = fadd reassoc float [[TMP1]], [[B:%.*]] ; CHECK-NEXT: [[TMP3:%.*]] = fsub reassoc float 0.000000e+00, [[A]] ; CHECK-NEXT: [[TMP4:%.*]] = fadd reassoc float [[TMP2]], [[TMP3]] ; CHECK-NEXT: ret float [[TMP4]] ; %1 = fadd reassoc float %a, 1234.0 %2 = fadd reassoc float %b, %1 %3 = fsub reassoc float 0.0, %a %4 = fadd reassoc float %2, %3 ret float %4 } ; X*-(Y*Z) -> X*-1*Y*Z ; That only works with both instcombine and reassociate passes enabled. ; Check that instcombine is not enough. define float @test16(float %a, float %b, float %z) { ; CHECK-LABEL: @test16( ; CHECK-NEXT: [[C:%.*]] = fneg fast float [[Z:%.*]] ; CHECK-NEXT: [[D:%.*]] = fmul fast float [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[E:%.*]] = fmul fast float [[D]], [[C]] ; CHECK-NEXT: [[G:%.*]] = fmul fast float [[E]], -1.234500e+04 ; CHECK-NEXT: ret float [[G]] ; %c = fsub fast float 0.000000e+00, %z %d = fmul fast float %a, %b %e = fmul fast float %c, %d %f = fmul fast float %e, 1.234500e+04 %g = fsub fast float 0.000000e+00, %f ret float %g } define float @test16_unary_fneg(float %a, float %b, float %z) { ; CHECK-LABEL: @test16_unary_fneg( ; CHECK-NEXT: [[C:%.*]] = fneg fast float [[Z:%.*]] ; CHECK-NEXT: [[D:%.*]] = fmul fast float [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[E:%.*]] = fmul fast float [[D]], [[C]] ; CHECK-NEXT: [[G:%.*]] = fmul fast float [[E]], -1.234500e+04 ; CHECK-NEXT: ret float [[G]] ; %c = fneg fast float %z %d = fmul fast float %a, %b %e = fmul fast float %c, %d %f = fmul fast float %e, 1.234500e+04 %g = fneg fast float %f ret float %g } define float @test16_reassoc_nsz(float %a, float %b, float %z) { ; CHECK-LABEL: @test16_reassoc_nsz( ; CHECK-NEXT: [[C:%.*]] = fneg reassoc nsz float [[Z:%.*]] ; CHECK-NEXT: [[D:%.*]] = fmul reassoc nsz float [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[E:%.*]] = fmul reassoc nsz float [[D]], [[C]] ; CHECK-NEXT: [[G:%.*]] = fmul reassoc nsz float [[E]], -1.234500e+04 ; CHECK-NEXT: ret float [[G]] ; %c = fsub reassoc nsz float 0.000000e+00, %z %d = fmul reassoc nsz float %a, %b %e = fmul reassoc nsz float %c, %d %f = fmul reassoc nsz float %e, 1.234500e+04 %g = fsub reassoc nsz float 0.000000e+00, %f ret float %g } define float @test16_reassoc(float %a, float %b, float %z) { ; CHECK-LABEL: @test16_reassoc( ; CHECK-NEXT: [[C:%.*]] = fsub reassoc float 0.000000e+00, [[Z:%.*]] ; CHECK-NEXT: [[D:%.*]] = fmul reassoc float [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[E:%.*]] = fmul reassoc float [[C]], [[D]] ; CHECK-NEXT: [[F:%.*]] = fmul reassoc float [[E]], 1.234500e+04 ; CHECK-NEXT: [[G:%.*]] = fsub reassoc float 0.000000e+00, [[F]] ; CHECK-NEXT: ret float [[G]] ; %c = fsub reassoc float 0.000000e+00, %z %d = fmul reassoc float %a, %b %e = fmul reassoc float %c, %d %f = fmul reassoc float %e, 1.234500e+04 %g = fsub reassoc float 0.000000e+00, %f ret float %g } define float @test17(float %a, float %b, float %z) { ; CHECK-LABEL: @test17( ; CHECK-NEXT: [[TMP1:%.*]] = fmul fast float [[Z:%.*]], 4.000000e+01 ; CHECK-NEXT: [[F:%.*]] = fmul fast float [[TMP1]], [[A:%.*]] ; CHECK-NEXT: ret float [[F]] ; %d = fmul fast float %z, 4.000000e+01 %c = fsub fast float 0.000000e+00, %d %e = fmul fast float %a, %c %f = fsub fast float 0.000000e+00, %e ret float %f } define float @test17_unary_fneg(float %a, float %b, float %z) { ; CHECK-LABEL: @test17_unary_fneg( ; CHECK-NEXT: [[TMP1:%.*]] = fmul fast float [[Z:%.*]], 4.000000e+01 ; CHECK-NEXT: [[F:%.*]] = fmul fast float [[TMP1]], [[A:%.*]] ; CHECK-NEXT: ret float [[F]] ; %d = fmul fast float %z, 4.000000e+01 %c = fneg fast float %d %e = fmul fast float %a, %c %f = fneg fast float %e ret float %f } define float @test17_reassoc_nsz(float %a, float %b, float %z) { ; CHECK-LABEL: @test17_reassoc_nsz( ; CHECK-NEXT: [[TMP1:%.*]] = fmul reassoc nsz float [[Z:%.*]], 4.000000e+01 ; CHECK-NEXT: [[F:%.*]] = fmul reassoc nsz float [[TMP1]], [[A:%.*]] ; CHECK-NEXT: ret float [[F]] ; %d = fmul reassoc nsz float %z, 4.000000e+01 %c = fsub reassoc nsz float 0.000000e+00, %d %e = fmul reassoc nsz float %a, %c %f = fsub reassoc nsz float 0.000000e+00, %e ret float %f } ; Verify the fold is not done with only 'reassoc' ('nsz' is required). define float @test17_reassoc(float %a, float %b, float %z) { ; CHECK-LABEL: @test17_reassoc( ; CHECK-NEXT: [[D:%.*]] = fmul reassoc float [[Z:%.*]], 4.000000e+01 ; CHECK-NEXT: [[C:%.*]] = fsub reassoc float 0.000000e+00, [[D]] ; CHECK-NEXT: [[E:%.*]] = fmul reassoc float [[C]], [[A:%.*]] ; CHECK-NEXT: [[F:%.*]] = fsub reassoc float 0.000000e+00, [[E]] ; CHECK-NEXT: ret float [[F]] ; %d = fmul reassoc float %z, 4.000000e+01 %c = fsub reassoc float 0.000000e+00, %d %e = fmul reassoc float %a, %c %f = fsub reassoc float 0.000000e+00, %e ret float %f } ; fneg of fneg is an identity operation, so no FMF are needed to remove those instructions. define float @test17_unary_fneg_no_FMF(float %a, float %b, float %z) { ; CHECK-LABEL: @test17_unary_fneg_no_FMF( ; CHECK-NEXT: [[TMP1:%.*]] = fmul float [[Z:%.*]], 4.000000e+01 ; CHECK-NEXT: [[F:%.*]] = fmul float [[TMP1]], [[A:%.*]] ; CHECK-NEXT: ret float [[F]] ; %d = fmul float %z, 4.000000e+01 %c = fneg float %d %e = fmul float %a, %c %f = fneg float %e ret float %f } define float @test17_reassoc_unary_fneg(float %a, float %b, float %z) { ; CHECK-LABEL: @test17_reassoc_unary_fneg( ; CHECK-NEXT: [[TMP1:%.*]] = fmul reassoc float [[Z:%.*]], 4.000000e+01 ; CHECK-NEXT: [[F:%.*]] = fmul reassoc float [[TMP1]], [[A:%.*]] ; CHECK-NEXT: ret float [[F]] ; %d = fmul reassoc float %z, 4.000000e+01 %c = fneg reassoc float %d %e = fmul reassoc float %a, %c %f = fneg reassoc float %e ret float %f } ; With sub reassociation, constant folding can eliminate the 12 and -12 constants. ; That only works with both instcombine and reassociate passes enabled. ; Check that instcombine is not enough. define float @test18(float %A, float %B) { ; CHECK-LABEL: @test18( ; CHECK-NEXT: [[X:%.*]] = fadd fast float [[A:%.*]], -1.200000e+01 ; CHECK-NEXT: [[Y:%.*]] = fsub fast float [[X]], [[B:%.*]] ; CHECK-NEXT: [[Z:%.*]] = fadd fast float [[Y]], 1.200000e+01 ; CHECK-NEXT: ret float [[Z]] ; %X = fadd fast float -1.200000e+01, %A %Y = fsub fast float %X, %B %Z = fadd fast float %Y, 1.200000e+01 ret float %Z } define float @test18_reassoc(float %A, float %B) { ; CHECK-LABEL: @test18_reassoc( ; CHECK-NEXT: [[X:%.*]] = fadd reassoc float [[A:%.*]], -1.200000e+01 ; CHECK-NEXT: [[Y:%.*]] = fsub reassoc float [[X]], [[B:%.*]] ; CHECK-NEXT: [[Z:%.*]] = fadd reassoc float [[Y]], 1.200000e+01 ; CHECK-NEXT: ret float [[Z]] ; %X = fadd reassoc float -1.200000e+01, %A %Y = fsub reassoc float %X, %B %Z = fadd reassoc float %Y, 1.200000e+01 ret float %Z } ; With sub reassociation, constant folding can eliminate the uses of %a. define float @test19(float %a, float %b, float %c) nounwind { ; CHECK-LABEL: @test19( ; CHECK-NEXT: [[TMP1:%.*]] = fadd fast float [[B:%.*]], [[C:%.*]] ; CHECK-NEXT: [[T7:%.*]] = fneg fast float [[TMP1]] ; CHECK-NEXT: ret float [[T7]] ; %t3 = fsub fast float %a, %b %t5 = fsub fast float %t3, %c %t7 = fsub fast float %t5, %a ret float %t7 } define float @test19_reassoc_nsz(float %a, float %b, float %c) nounwind { ; CHECK-LABEL: @test19_reassoc_nsz( ; CHECK-NEXT: [[TMP1:%.*]] = fadd reassoc nsz float [[B:%.*]], [[C:%.*]] ; CHECK-NEXT: [[T7:%.*]] = fneg reassoc nsz float [[TMP1]] ; CHECK-NEXT: ret float [[T7]] ; %t3 = fsub reassoc nsz float %a, %b %t5 = fsub reassoc nsz float %t3, %c %t7 = fsub reassoc nsz float %t5, %a ret float %t7 } ; Verify the fold is not done with only 'reassoc' ('nsz' is required). define float @test19_reassoc(float %a, float %b, float %c) nounwind { ; CHECK-LABEL: @test19_reassoc( ; CHECK-NEXT: [[T3:%.*]] = fsub reassoc float [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: [[T5:%.*]] = fsub reassoc float [[T3]], [[C:%.*]] ; CHECK-NEXT: [[T7:%.*]] = fsub reassoc float [[T5]], [[A]] ; CHECK-NEXT: ret float [[T7]] ; %t3 = fsub reassoc float %a, %b %t5 = fsub reassoc float %t3, %c %t7 = fsub reassoc float %t5, %a ret float %t7 }