diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -11919,6 +11919,29 @@ N1.getOperand(0), N1.getOperand(1), N0, Flags); } + // fadd (fma A, B, (fmul C, D)), E --> fma A, B, (fma C, D, E) + // fadd E, (fma A, B, (fmul C, D)) --> fma A, B, (fma C, D, E) + SDValue FMA, E; + if (CanFuse && N0.getOpcode() == PreferredFusedOpcode && + N0.getOperand(2).getOpcode() == ISD::FMUL && N0.hasOneUse() && + N0.getOperand(2).hasOneUse()) { + FMA = N0; + E = N1; + } else if (CanFuse && N1.getOpcode() == PreferredFusedOpcode && + N1.getOperand(2).getOpcode() == ISD::FMUL && N1.hasOneUse() && + N1.getOperand(2).hasOneUse()) { + FMA = N1; + E = N0; + } + if (FMA && E) { + SDValue A = FMA.getOperand(0); + SDValue B = FMA.getOperand(1); + SDValue C = FMA.getOperand(2).getOperand(0); + SDValue D = FMA.getOperand(2).getOperand(1); + SDValue CDE = DAG.getNode(PreferredFusedOpcode, SL, VT, C, D, E, Flags); + return DAG.getNode(PreferredFusedOpcode, SL, VT, A, B, CDE, Flags); + } + // Look through FP_EXTEND nodes to do more combining. // fold (fadd (fpext (fmul x, y)), z) -> (fma (fpext x), (fpext y), z) @@ -11952,29 +11975,6 @@ // More folding opportunities when target permits. if (Aggressive) { - // fadd (fma A, B, (fmul C, D)), E --> fma A, B, (fma C, D, E) - // fadd E, (fma A, B, (fmul C, D)) --> fma A, B, (fma C, D, E) - SDValue FMA, E; - if (CanFuse && N0.getOpcode() == PreferredFusedOpcode && - N0.getOperand(2).getOpcode() == ISD::FMUL && N0.hasOneUse() && - N0.getOperand(2).hasOneUse()) { - FMA = N0; - E = N1; - } else if (CanFuse && N1.getOpcode() == PreferredFusedOpcode && - N1.getOperand(2).getOpcode() == ISD::FMUL && N1.hasOneUse() && - N1.getOperand(2).hasOneUse()) { - FMA = N1; - E = N0; - } - if (FMA && E) { - SDValue A = FMA.getOperand(0); - SDValue B = FMA.getOperand(1); - SDValue C = FMA.getOperand(2).getOperand(0); - SDValue D = FMA.getOperand(2).getOperand(1); - SDValue CDE = DAG.getNode(PreferredFusedOpcode, SL, VT, C, D, E, Flags); - return DAG.getNode(PreferredFusedOpcode, SL, VT, A, B, CDE, Flags); - } - // fold (fadd (fma x, y, (fpext (fmul u, v))), z) // -> (fma x, y, (fma (fpext u), (fpext v), z)) auto FoldFAddFMAFPExtFMul = [&] ( diff --git a/llvm/test/CodeGen/AArch64/fadd-combines.ll b/llvm/test/CodeGen/AArch64/fadd-combines.ll --- a/llvm/test/CodeGen/AArch64/fadd-combines.ll +++ b/llvm/test/CodeGen/AArch64/fadd-combines.ll @@ -197,9 +197,8 @@ define double @fadd_fma_fmul_1(double %a, double %b, double %c, double %d, double %n1) nounwind { ; CHECK-LABEL: fadd_fma_fmul_1: ; CHECK: // %bb.0: -; CHECK-NEXT: fmul d2, d2, d3 +; CHECK-NEXT: fmadd d2, d2, d3, d4 ; CHECK-NEXT: fmadd d0, d0, d1, d2 -; CHECK-NEXT: fadd d0, d0, d4 ; CHECK-NEXT: ret %m1 = fmul fast double %a, %b %m2 = fmul fast double %c, %d @@ -213,9 +212,8 @@ define float @fadd_fma_fmul_2(float %a, float %b, float %c, float %d, float %n0) nounwind { ; CHECK-LABEL: fadd_fma_fmul_2: ; CHECK: // %bb.0: -; CHECK-NEXT: fmul s2, s2, s3 +; CHECK-NEXT: fmadd s2, s2, s3, s4 ; CHECK-NEXT: fmadd s0, s0, s1, s2 -; CHECK-NEXT: fadd s0, s4, s0 ; CHECK-NEXT: ret %m1 = fmul float %a, %b %m2 = fmul float %c, %d @@ -230,10 +228,10 @@ ; CHECK-LABEL: fadd_fma_fmul_3: ; CHECK: // %bb.0: ; CHECK-NEXT: fmul v2.2d, v2.2d, v3.2d -; CHECK-NEXT: fmul v3.2d, v6.2d, v7.2d ; CHECK-NEXT: fmla v2.2d, v1.2d, v0.2d -; CHECK-NEXT: fmla v3.2d, v5.2d, v4.2d -; CHECK-NEXT: fadd v0.2d, v2.2d, v3.2d +; CHECK-NEXT: fmla v2.2d, v7.2d, v6.2d +; CHECK-NEXT: fmla v2.2d, v5.2d, v4.2d +; CHECK-NEXT: mov v0.16b, v2.16b ; CHECK-NEXT: ret %m1 = fmul fast <2 x double> %x1, %x2 %m2 = fmul fast <2 x double> %x3, %x4 @@ -245,6 +243,8 @@ ret <2 x double> %a3 } +; negative test + define float @fadd_fma_fmul_extra_use_1(float %a, float %b, float %c, float %d, float %n0, float* %p) nounwind { ; CHECK-LABEL: fadd_fma_fmul_extra_use_1: ; CHECK: // %bb.0: @@ -261,6 +261,8 @@ ret float %a2 } +; negative test + define float @fadd_fma_fmul_extra_use_2(float %a, float %b, float %c, float %d, float %n0, float* %p) nounwind { ; CHECK-LABEL: fadd_fma_fmul_extra_use_2: ; CHECK: // %bb.0: @@ -277,6 +279,8 @@ ret float %a2 } +; negative test + define float @fadd_fma_fmul_extra_use_3(float %a, float %b, float %c, float %d, float %n0, float* %p) nounwind { ; CHECK-LABEL: fadd_fma_fmul_extra_use_3: ; CHECK: // %bb.0: diff --git a/llvm/test/CodeGen/X86/fma_patterns.ll b/llvm/test/CodeGen/X86/fma_patterns.ll --- a/llvm/test/CodeGen/X86/fma_patterns.ll +++ b/llvm/test/CodeGen/X86/fma_patterns.ll @@ -1799,23 +1799,20 @@ define double @fadd_fma_fmul_1(double %a, double %b, double %c, double %d, double %n1) nounwind { ; FMA-LABEL: fadd_fma_fmul_1: ; FMA: # %bb.0: -; FMA-NEXT: vmulsd %xmm3, %xmm2, %xmm2 -; FMA-NEXT: vfmadd231sd {{.*#+}} xmm2 = (xmm1 * xmm0) + xmm2 -; FMA-NEXT: vaddsd %xmm4, %xmm2, %xmm0 +; FMA-NEXT: vfmadd213sd {{.*#+}} xmm2 = (xmm3 * xmm2) + xmm4 +; FMA-NEXT: vfmadd213sd {{.*#+}} xmm0 = (xmm1 * xmm0) + xmm2 ; FMA-NEXT: retq ; ; FMA4-LABEL: fadd_fma_fmul_1: ; FMA4: # %bb.0: -; FMA4-NEXT: vmulsd %xmm3, %xmm2, %xmm2 +; FMA4-NEXT: vfmaddsd {{.*#+}} xmm2 = (xmm2 * xmm3) + xmm4 ; FMA4-NEXT: vfmaddsd {{.*#+}} xmm0 = (xmm0 * xmm1) + xmm2 -; FMA4-NEXT: vaddsd %xmm4, %xmm0, %xmm0 ; FMA4-NEXT: retq ; ; AVX512-LABEL: fadd_fma_fmul_1: ; AVX512: # %bb.0: -; AVX512-NEXT: vmulsd %xmm3, %xmm2, %xmm2 -; AVX512-NEXT: vfmadd231sd {{.*#+}} xmm2 = (xmm1 * xmm0) + xmm2 -; AVX512-NEXT: vaddsd %xmm4, %xmm2, %xmm0 +; AVX512-NEXT: vfmadd213sd {{.*#+}} xmm2 = (xmm3 * xmm2) + xmm4 +; AVX512-NEXT: vfmadd213sd {{.*#+}} xmm0 = (xmm1 * xmm0) + xmm2 ; AVX512-NEXT: retq %m1 = fmul fast double %a, %b %m2 = fmul fast double %c, %d @@ -1829,23 +1826,20 @@ define float @fadd_fma_fmul_2(float %a, float %b, float %c, float %d, float %n0) nounwind { ; FMA-LABEL: fadd_fma_fmul_2: ; FMA: # %bb.0: -; FMA-NEXT: vmulss %xmm3, %xmm2, %xmm2 -; FMA-NEXT: vfmadd231ss {{.*#+}} xmm2 = (xmm1 * xmm0) + xmm2 -; FMA-NEXT: vaddss %xmm2, %xmm4, %xmm0 +; FMA-NEXT: vfmadd213ss {{.*#+}} xmm2 = (xmm3 * xmm2) + xmm4 +; FMA-NEXT: vfmadd213ss {{.*#+}} xmm0 = (xmm1 * xmm0) + xmm2 ; FMA-NEXT: retq ; ; FMA4-LABEL: fadd_fma_fmul_2: ; FMA4: # %bb.0: -; FMA4-NEXT: vmulss %xmm3, %xmm2, %xmm2 +; FMA4-NEXT: vfmaddss {{.*#+}} xmm2 = (xmm2 * xmm3) + xmm4 ; FMA4-NEXT: vfmaddss {{.*#+}} xmm0 = (xmm0 * xmm1) + xmm2 -; FMA4-NEXT: vaddss %xmm0, %xmm4, %xmm0 ; FMA4-NEXT: retq ; ; AVX512-LABEL: fadd_fma_fmul_2: ; AVX512: # %bb.0: -; AVX512-NEXT: vmulss %xmm3, %xmm2, %xmm2 -; AVX512-NEXT: vfmadd231ss {{.*#+}} xmm2 = (xmm1 * xmm0) + xmm2 -; AVX512-NEXT: vaddss %xmm2, %xmm4, %xmm0 +; AVX512-NEXT: vfmadd213ss {{.*#+}} xmm2 = (xmm3 * xmm2) + xmm4 +; AVX512-NEXT: vfmadd213ss {{.*#+}} xmm0 = (xmm1 * xmm0) + xmm2 ; AVX512-NEXT: retq %m1 = fmul float %a, %b %m2 = fmul float %c, %d @@ -1860,28 +1854,27 @@ ; FMA-LABEL: fadd_fma_fmul_3: ; FMA: # %bb.0: ; FMA-NEXT: vmulpd %xmm3, %xmm2, %xmm2 -; FMA-NEXT: vmulpd %xmm7, %xmm6, %xmm3 ; FMA-NEXT: vfmadd231pd {{.*#+}} xmm2 = (xmm1 * xmm0) + xmm2 -; FMA-NEXT: vfmadd231pd {{.*#+}} xmm3 = (xmm5 * xmm4) + xmm3 -; FMA-NEXT: vaddpd %xmm3, %xmm2, %xmm0 +; FMA-NEXT: vfmadd231pd {{.*#+}} xmm2 = (xmm7 * xmm6) + xmm2 +; FMA-NEXT: vfmadd231pd {{.*#+}} xmm2 = (xmm5 * xmm4) + xmm2 +; FMA-NEXT: vmovapd %xmm2, %xmm0 ; FMA-NEXT: retq ; ; FMA4-LABEL: fadd_fma_fmul_3: ; FMA4: # %bb.0: ; FMA4-NEXT: vmulpd %xmm3, %xmm2, %xmm2 -; FMA4-NEXT: vmulpd %xmm7, %xmm6, %xmm3 ; FMA4-NEXT: vfmaddpd {{.*#+}} xmm0 = (xmm0 * xmm1) + xmm2 -; FMA4-NEXT: vfmaddpd {{.*#+}} xmm1 = (xmm4 * xmm5) + xmm3 -; FMA4-NEXT: vaddpd %xmm1, %xmm0, %xmm0 +; FMA4-NEXT: vfmaddpd {{.*#+}} xmm0 = (xmm6 * xmm7) + xmm0 +; FMA4-NEXT: vfmaddpd {{.*#+}} xmm0 = (xmm4 * xmm5) + xmm0 ; FMA4-NEXT: retq ; ; AVX512-LABEL: fadd_fma_fmul_3: ; AVX512: # %bb.0: ; AVX512-NEXT: vmulpd %xmm3, %xmm2, %xmm2 -; AVX512-NEXT: vmulpd %xmm7, %xmm6, %xmm3 ; AVX512-NEXT: vfmadd231pd {{.*#+}} xmm2 = (xmm1 * xmm0) + xmm2 -; AVX512-NEXT: vfmadd231pd {{.*#+}} xmm3 = (xmm5 * xmm4) + xmm3 -; AVX512-NEXT: vaddpd %xmm3, %xmm2, %xmm0 +; AVX512-NEXT: vfmadd231pd {{.*#+}} xmm2 = (xmm7 * xmm6) + xmm2 +; AVX512-NEXT: vfmadd231pd {{.*#+}} xmm2 = (xmm5 * xmm4) + xmm2 +; AVX512-NEXT: vmovapd %xmm2, %xmm0 ; AVX512-NEXT: retq %m1 = fmul fast <2 x double> %x1, %x2 %m2 = fmul fast <2 x double> %x3, %x4 @@ -1893,6 +1886,8 @@ ret <2 x double> %a3 } +; negative test + define float @fadd_fma_fmul_extra_use_1(float %a, float %b, float %c, float %d, float %n0, float* %p) nounwind { ; FMA-LABEL: fadd_fma_fmul_extra_use_1: ; FMA: # %bb.0: @@ -1925,6 +1920,8 @@ ret float %a2 } +; negative test + define float @fadd_fma_fmul_extra_use_2(float %a, float %b, float %c, float %d, float %n0, float* %p) nounwind { ; FMA-LABEL: fadd_fma_fmul_extra_use_2: ; FMA: # %bb.0: @@ -1957,6 +1954,8 @@ ret float %a2 } +; negative test + define float @fadd_fma_fmul_extra_use_3(float %a, float %b, float %c, float %d, float %n0, float* %p) nounwind { ; FMA-LABEL: fadd_fma_fmul_extra_use_3: ; FMA: # %bb.0: