Utilize new SDNode flag functionality to expand current support for fma

[mcberg2017]

Summary

This patch originated from D47388 and is a proper subset of the originating changes, containing only the fmf optimization guard extensions.

[mcberg2017]

test/CodeGen/PowerPC/fmf-propagation.ll

308

No worries here, this is cross patching cruft, next update will have this sync up.

[mcberg2017]

with the cleanup...

[spatel]

test/CodeGen/X86/fmf-flags_fma.ll

2

avx2 shouldn't be necessary?

10–11

This case is already folded independently of this patch, right?
Please check in all new tests with current codegen as a preliminary step.

The case where this patch will make a difference is something like this?

define float @fadd_contract_with_strict_fmul(float %a , float %b , float %c) {
  %m = fmul float %a, %b
  %a = fadd contract float %m, %c
  ret float %a
}

[mcberg2017]

Removed an already covered test and avx2 requirement for testing.

[mcberg2017]

TBD, check in tests first...

[mcberg2017]

test/CodeGen/AArch64/fma-aggressive.ll and test/CodeGen/X86/fmf-flags_fma.ll behave the same before and after the addition of this code, I will drop them for the next upload, and only one test file has changes, test/CodeGen/AArch64/neon-fma-FMF.ll, which I will check in.
The other two tests just have changed behavior with this code change and will remain unmodified until this code is checked in.

[mcberg2017]

Synced up after rL334461, with fewer test files.

[spatel]

Adding more potential FMA reviewers. There may be some tricky bits here in the interaction between the FMF, the global settings, and the TLI hooks. See for example D28675.

IMO, we need to add more tests -- particularly for the targets that these folds were originally applied to (mostly AMDGPU).

[nhaehnle]

We do have tests for those in AMDGPU, with -enable-unsafe-fp-math. We don't have systematic tests with the new contract/reassoc bits. At least the Mesa frontend doesn't generate those anyway at the moment.

@tpr, @rampitec maybe you want to add some tests for those for HSA / LLPC? I don't know if you're using the new bits yet.

In any case, the change looks good to me.

[arsenm]

In D47918#1133384, @nhaehnle wrote:

We do have tests for those in AMDGPU, with -enable-unsafe-fp-math. We don't have systematic tests with the new contract/reassoc bits. At least the Mesa frontend doesn't generate those anyway at the moment.

@tpr, @rampitec maybe you want to add some tests for those for HSA / LLPC? I don't know if you're using the new bits yet.

In any case, the change looks good to me.

We should mostly just convert all the tests using the global flag to using the per-instruction ones.

The HSA case just inherits them from clang if its using them, which I assume it is.

[rampitec]

In D47918#1133473, @arsenm wrote:

In D47918#1133384, @nhaehnle wrote:

We do have tests for those in AMDGPU, with -enable-unsafe-fp-math. We don't have systematic tests with the new contract/reassoc bits. At least the Mesa frontend doesn't generate those anyway at the moment.

@tpr, @rampitec maybe you want to add some tests for those for HSA / LLPC? I don't know if you're using the new bits yet.

In any case, the change looks good to me.

We should mostly just convert all the tests using the global flag to using the per-instruction ones.

The HSA case just inherits them from clang if its using them, which I assume it is.

Yes, we have the tests an can modify/duplicate them to use individual flags.
However, speaking of interaction with clang supposed to produce it I really have hard time not to get llvm.fmuladd.f32 call right from the clang, even at -O0. Which makes me think from a practical point of view we will not see any real codegen difference. Well, at least if I use OpenCL.

[rampitec]

LGTM

lib/CodeGen/SelectionDAG/DAGCombiner.cpp

bool HasFMA =
       TLI.isFMAFasterThanFMulAndFAdd(VT) &&
       (!LegalOperations || TLI.isOperationLegalOrCustom(ISD::FMA, VT));
 
   // No valid opcode, do not combine.
   if (!HasFMAD && !HasFMA)
     return SDValue();
 
   SDNodeFlags Flags = N->getFlags();
+  bool CanFuse = Options.UnsafeFPMath || isContractable(N);
   bool AllowFusionGlobally = (Options.AllowFPOpFusion == FPOpFusion::Fast ||
-                              Options.UnsafeFPMath || HasFMAD);
+                              CanFuse || HasFMAD);
   // If the addition is not contractable, do not combine.
   if (!AllowFusionGlobally && !isContractable(N))
     return SDValue();
 
   const SelectionDAGTargetInfo *STI = DAG.getSubtarget().getSelectionDAGInfo();
   if (STI && STI->generateFMAsInMachineCombiner(OptLevel))
     return SDValue();
 
if (isContractableFMUL(N10) &&
                          DAG.getNode(ISD::FP_EXTEND, SL, VT,
                                      N10.getOperand(1)), N0, Flags);
     }
   }
 
   // More folding opportunities when target permits.
   if (Aggressive) {
     // fold (fadd (fma x, y, (fmul u, v)), z) -> (fma x, y (fma u, v, z))
-    // FIXME: The UnsafeAlgebra flag should be propagated to FMA/FMAD, but FMF
-    // are currently only supported on binary nodes.
-    if (Options.UnsafeFPMath &&
+    if (CanFuse &&
         N0.getOpcode() == PreferredFusedOpcode &&
         N0.getOperand(2).getOpcode() == ISD::FMUL &&
         N0->hasOneUse() && N0.getOperand(2)->hasOneUse()) {
       return DAG.getNode(PreferredFusedOpcode, SL, VT,
                          N0.getOperand(0), N0.getOperand(1),
                          DAG.getNode(PreferredFusedOpcode, SL, VT,
                                      N0.getOperand(2).getOperand(0),
                                      N0.getOperand(2).getOperand(1),
                                      N1, Flags), Flags);
     }
 
     // fold (fadd x, (fma y, z, (fmul u, v)) -> (fma y, z (fma u, v, x))
-    // FIXME: The UnsafeAlgebra flag should be propagated to FMA/FMAD, but FMF
-    // are currently only supported on binary nodes.
-    if (Options.UnsafeFPMath &&
+    if (CanFuse &&
         N1->getOpcode() == PreferredFusedOpcode &&
         N1.getOperand(2).getOpcode() == ISD::FMUL &&
         N1->hasOneUse() && N1.getOperand(2)->hasOneUse()) {
       return DAG.getNode(PreferredFusedOpcode, SL, VT,
                          N1.getOperand(0), N1.getOperand(1),
                          DAG.getNode(PreferredFusedOpcode, SL, VT,
                                      N1.getOperand(2).getOperand(0),
                                      N1.getOperand(2).getOperand(1),
bool HasFMA =
       TLI.isFMAFasterThanFMulAndFAdd(VT) &&
       (!LegalOperations || TLI.isOperationLegalOrCustom(ISD::FMA, VT));
 
   // No valid opcode, do not combine.
   if (!HasFMAD && !HasFMA)
     return SDValue();
 
   const SDNodeFlags Flags = N->getFlags();
+  bool CanFuse = Options.UnsafeFPMath || isContractable(N);
   bool AllowFusionGlobally = (Options.AllowFPOpFusion == FPOpFusion::Fast ||
-                              Options.UnsafeFPMath || HasFMAD);
+                              CanFuse || HasFMAD);
 
   // If the subtraction is not contractable, do not combine.
   if (!AllowFusionGlobally && !isContractable(N))
     return SDValue();
 
   const SelectionDAGTargetInfo *STI = DAG.getSubtarget().getSelectionDAGInfo();
   if (STI && STI->generateFMAsInMachineCombiner(OptLevel))
     return SDValue();
SDValue DAGCombiner::visitFSUBForFMACombine(SDNode *N) {
   if (isContractableFMUL(N0) && (Aggressive || N0->hasOneUse())) {
     return DAG.getNode(PreferredFusedOpcode, SL, VT,
                        N0.getOperand(0), N0.getOperand(1),
                        DAG.getNode(ISD::FNEG, SL, VT, N1), Flags);
   }
 
   // fold (fsub x, (fmul y, z)) -> (fma (fneg y), z, x)
   // Note: Commutes FSUB operands.
-  if (isContractableFMUL(N1) && (Aggressive || N1->hasOneUse()))
+  if (isContractableFMUL(N1) && (Aggressive || N1->hasOneUse())) {
     return DAG.getNode(PreferredFusedOpcode, SL, VT,
                        DAG.getNode(ISD::FNEG, SL, VT,
                                    N1.getOperand(0)),
                        N1.getOperand(1), N0, Flags);
+  }
 
   // fold (fsub (fneg (fmul, x, y)), z) -> (fma (fneg x), y, (fneg z))
   if (N0.getOpcode() == ISD::FNEG && isContractableFMUL(N0.getOperand(0)) &&
       (Aggressive || (N0->hasOneUse() && N0.getOperand(0).hasOneUse()))) {
     SDValue N00 = N0.getOperand(0).getOperand(0);
     SDValue N01 = N0.getOperand(0).getOperand(1);
     return DAG.getNode(PreferredFusedOpcode, SL, VT,
                        DAG.getNode(ISD::FNEG, SL, VT, N00), N01,
if (N00.getOpcode() == ISD::FP_EXTEND) {
       }
     }
   }
 
   // More folding opportunities when target permits.
   if (Aggressive) {
     // fold (fsub (fma x, y, (fmul u, v)), z)
     //   -> (fma x, y (fma u, v, (fneg z)))
-    // FIXME: The UnsafeAlgebra flag should be propagated to FMA/FMAD, but FMF
-    // are currently only supported on binary nodes.
-    if (Options.UnsafeFPMath && N0.getOpcode() == PreferredFusedOpcode &&
+    if (CanFuse && N0.getOpcode() == PreferredFusedOpcode &&
         isContractableFMUL(N0.getOperand(2)) && N0->hasOneUse() &&
         N0.getOperand(2)->hasOneUse()) {
       return DAG.getNode(PreferredFusedOpcode, SL, VT,
                          N0.getOperand(0), N0.getOperand(1),
                          DAG.getNode(PreferredFusedOpcode, SL, VT,
                                      N0.getOperand(2).getOperand(0),
                                      N0.getOperand(2).getOperand(1),
                                      DAG.getNode(ISD::FNEG, SL, VT,
                                                  N1), Flags), Flags);          
     }
 
     // fold (fsub x, (fma y, z, (fmul u, v)))
     //   -> (fma (fneg y), z, (fma (fneg u), v, x))
-    // FIXME: The UnsafeAlgebra flag should be propagated to FMA/FMAD, but FMF
-    // are currently only supported on binary nodes.
-    if (Options.UnsafeFPMath && N1.getOpcode() == PreferredFusedOpcode &&
+    if (CanFuse && N1.getOpcode() == PreferredFusedOpcode &&
         isContractableFMUL(N1.getOperand(2))) {
       SDValue N20 = N1.getOperand(2).getOperand(0);
       SDValue N21 = N1.getOperand(2).getOperand(1);
       return DAG.getNode(PreferredFusedOpcode, SL, VT,
                          DAG.getNode(ISD::FNEG, SL, VT,
                                      N1.getOperand(0)),
                          N1.getOperand(1),
                          DAG.getNode(PreferredFusedOpcode, SL, VT,
SDValue DAGCombiner::visitFMA(SDNode *N) {
   ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
   ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
   EVT VT = N->getValueType(0);
   SDLoc DL(N);
   const TargetOptions &Options = DAG.getTarget().Options;
 
   // FMA nodes have flags that propagate to the created nodes.
   const SDNodeFlags Flags = N->getFlags();
+  bool UnsafeFPMath = Options.UnsafeFPMath || isContractable(N);
 
   // Constant fold FMA.
   if (isa<ConstantFPSDNode>(N0) &&
       isa<ConstantFPSDNode>(N1) &&
       isa<ConstantFPSDNode>(N2)) {
     return DAG.getNode(ISD::FMA, DL, VT, N0, N1, N2);
   }
 
-  if (Options.UnsafeFPMath) {
+  if (UnsafeFPMath) {
     if (N0CFP && N0CFP->isZero())
       return N2;
     if (N1CFP && N1CFP->isZero())
       return N2;
   }
   // TODO: The FMA node should have flags that propagate to these nodes.
   if (N0CFP && N0CFP->isExactlyValue(1.0))
     return DAG.getNode(ISD::FADD, SDLoc(N), VT, N1, N2);
   if (N1CFP && N1CFP->isExactlyValue(1.0))
     return DAG.getNode(ISD::FADD, SDLoc(N), VT, N0, N2);
 
   // Canonicalize (fma c, x, y) -> (fma x, c, y)
   if (isConstantFPBuildVectorOrConstantFP(N0) &&
      !isConstantFPBuildVectorOrConstantFP(N1))
     return DAG.getNode(ISD::FMA, SDLoc(N), VT, N1, N0, N2);
 
-  if (Options.UnsafeFPMath) {
+  if (UnsafeFPMath) {
     // (fma x, c1, (fmul x, c2)) -> (fmul x, c1+c2)
     if (N2.getOpcode() == ISD::FMUL && N0 == N2.getOperand(0) &&
         isConstantFPBuildVectorOrConstantFP(N1) &&
         isConstantFPBuildVectorOrConstantFP(N2.getOperand(1))) {
       return DAG.getNode(ISD::FMUL, DL, VT, N0,
                          DAG.getNode(ISD::FADD, DL, VT, N1, N2.getOperand(1),
                                      Flags), Flags);
     }
if (N1CFP) {
     if (N0.getOpcode() == ISD::FNEG &&
         (TLI.isOperationLegal(ISD::ConstantFP, VT) ||
          (N1.hasOneUse() && !TLI.isFPImmLegal(N1CFP->getValueAPF(), VT)))) {
       return DAG.getNode(ISD::FMA, DL, VT, N0.getOperand(0),
                          DAG.getNode(ISD::FNEG, DL, VT, N1, Flags), N2);
     }
   }
 
-  if (Options.UnsafeFPMath) {
+  if (UnsafeFPMath) {
     // (fma x, c, x) -> (fmul x, (c+1))
     if (N1CFP && N0 == N2) {
       return DAG.getNode(ISD::FMUL, DL, VT, N0,
                          DAG.getNode(ISD::FADD, DL, VT, N1,
                                      DAG.getConstantFP(1.0, DL, VT), Flags),
                          Flags);
     }
 

test/CodeGen/AArch64/fma-aggressive.ll

+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=aarch64-linux-gnu -mcpu=thunderx2t99 < %s | FileCheck %s
+
+define float @test1(float %u , float %v , float %x, float %y, float %z) {
+; CHECK-LABEL: test1
+; CHECK-EVEN: fmadd {{s[0-9]*[02468]}}, {{s[0-9]*}}, {{s[0-9]*}}, {{s[0-9]*[02468]}}
+; CHECK-EVEN: fmadd {{s[0-9]*[02468]}}, {{s[0-9]*}}, {{s[0-9]*}}, {{s[0-9]*[02468]}}
+  %mul.1 = fmul fast float %u, %v
+  %mul.2 = fmul fast float %x, %y
+  %fma = fadd fast float %mul.2, %mul.1
+  %res = fadd fast float %fma, %z
+  ret float %res
+}
+
+define float @test2(float %u , float %v , float %x, float %y, float %z) {
+; CHECK-LABEL: test2
+; CHECK-EVEN: fmadd {{s[0-9]*[02468]}}, {{s[0-9]*}}, {{s[0-9]*}}, {{s[0-9]*[02468]}}
+; CHECK-EVEN: fmadd {{s[0-9]*[02468]}}, {{s[0-9]*}}, {{s[0-9]*}}, {{s[0-9]*[02468]}}
+  %mul.1 = fmul fast float %y, %z
+  %mul.2 = fmul fast float %u, %v
+  %fma = fadd fast float %mul.2, %mul.1
+  %res = fadd fast float %x, %fma
+  ret float %res
+}
+
+define float @test3(float %u , float %v , float %x, float %y, float %z) {
+; CHECK-LABEL: test3
+; CHECK-EVEN: fnmsub {{s[0-9]*[02468]}}, {{s[0-9]*}}, {{s[0-9]*}}, {{s[0-9]*[02468]}}
+  %mul.1 = fmul fast float %x, %y
+  %res = fsub fast float %mul.1, %z
+  ret float %res
+}
+
+define float @test4(float %u , float %v , float %x, float %y, float %z) {
+; CHECK-LABEL: test4
+; CHECK-EVEN: fnmadd {{s[0-9]*[02468]}}, {{s[0-9]*}}, {{s[0-9]*}}, {{s[0-9]*[02468]}}
+  %mul.1 = fmul fast float %x, %y
+  %neg = fsub fast float -0.0, %mul.1
+  %res = fsub fast float %neg, %z
+  ret float %res
+}

test/CodeGen/AArch64/neon-fma-FMF.ll

 ; RUN: llc < %s -verify-machineinstrs -mtriple=aarch64-none-linux-gnu -mattr=+neon | FileCheck %s
 
-define <2 x float> @fma(<2 x float> %A, <2 x float> %B, <2 x float> %C) {
-; CHECK-LABEL: fma:
+define <2 x float> @fma_1(<2 x float> %A, <2 x float> %B, <2 x float> %C) {
+; CHECK-LABEL: fma_1:
 ; CHECK: fmla {{v[0-9]+}}.2s, {{v[0-9]+}}.2s, {{v[0-9]+}}.2s
   %tmp1 = fmul contract <2 x float> %A, %B;
   %tmp2 = fadd contract <2 x float> %C, %tmp1;
   ret <2 x float> %tmp2
 }
 
+; This case will fold as it was only available through unsafe before, now available from
+; the contract on the fadd
+define <2 x float> @fma_2(<2 x float> %A, <2 x float> %B, <2 x float> %C) {
+; CHECK-LABEL: fma_2:
+; CHECK: fmla {{v[0-9]+}}.2s, {{v[0-9]+}}.2s, {{v[0-9]+}}.2s
+  %tmp1 = fmul <2 x float> %A, %B;
+  %tmp2 = fadd contract <2 x float> %C, %tmp1;
+  ret <2 x float> %tmp2
+}
+
 define <2 x float> @no_fma_1(<2 x float> %A, <2 x float> %B, <2 x float> %C) {
 ; CHECK-LABEL: no_fma_1:
 ; CHECK: fmul
 ; CHECK: fadd
   %tmp1 = fmul contract <2 x float> %A, %B;
   %tmp2 = fadd <2 x float> %C, %tmp1;
   ret <2 x float> %tmp2
 }
 
-define <2 x float> @no_fma_2(<2 x float> %A, <2 x float> %B, <2 x float> %C) {
-; CHECK-LABEL: no_fma_2:
-; CHECK: fmul
-; CHECK: fadd
-  %tmp1 = fmul <2 x float> %A, %B;
-  %tmp2 = fadd contract <2 x float> %C, %tmp1;
+define <2 x float> @fma_sub_1(<2 x float> %A, <2 x float> %B, <2 x float> %C) {
+; CHECK-LABEL: fma_sub_1:
+; CHECK: fmls {{v[0-9]+}}.2s, {{v[0-9]+}}.2s, {{v[0-9]+}}.2s
+  %tmp1 = fmul contract <2 x float> %A, %B;
+  %tmp2 = fsub contract <2 x float> %C, %tmp1;
   ret <2 x float> %tmp2
 }
 
-define <2 x float> @fma_sub(<2 x float> %A, <2 x float> %B, <2 x float> %C) {
-; CHECK-LABEL: fma_sub:
+; This case will fold as it was only available through unsafe before, now available from
+; the contract on the fsub
+define <2 x float> @fma_sub_2(<2 x float> %A, <2 x float> %B, <2 x float> %C) {
+; CHECK-LABEL: fma_sub_2:
 ; CHECK: fmls {{v[0-9]+}}.2s, {{v[0-9]+}}.2s, {{v[0-9]+}}.2s
-  %tmp1 = fmul contract <2 x float> %A, %B;
+  %tmp1 = fmul <2 x float> %A, %B;
   %tmp2 = fsub contract <2 x float> %C, %tmp1;
   ret <2 x float> %tmp2
 }
 
 define <2 x float> @no_fma_sub_1(<2 x float> %A, <2 x float> %B, <2 x float> %C) {
 ; CHECK-LABEL: no_fma_sub_1:
 ; CHECK: fmul
 ; CHECK: fsub
   %tmp1 = fmul contract <2 x float> %A, %B;
   %tmp2 = fsub <2 x float> %C, %tmp1;
   ret <2 x float> %tmp2
 }
-
-define <2 x float> @no_fma_sub_2(<2 x float> %A, <2 x float> %B, <2 x float> %C) {
-; CHECK-LABEL: no_fma_sub_2:
-; CHECK: fmul
-; CHECK: fsub
-  %tmp1 = fmul <2 x float> %A, %B;
-  %tmp2 = fsub contract <2 x float> %C, %tmp1;
-  ret <2 x float> %tmp2
-}

test/CodeGen/PowerPC/fma-aggr-FMF.ll

 }
 
 ; There is no contract on the mul with no extra use so we can't fuse that.
 ; Since we are fusing with the mul with an extra use, the fmul needs to stick
 ; around beside the fma.
 define float @no_fma_with_fewer_uses(float %f1, float %f2, float %f3, float %f4) {
 ; CHECK-LABEL: no_fma_with_fewer_uses:
 ; CHECK:       # %bb.0:
-; CHECK-NEXT:    xsmulsp 0, 3, 4
-; CHECK-NEXT:    xsmulsp 13, 1, 2
-; CHECK-NEXT:    xsmaddasp 0, 1, 2
-; CHECK-NEXT:    xsdivsp 1, 13, 0
+; CHECK-NEXT:    xsmulsp 0, 1, 2
+; CHECK-NEXT:    fmr 1, 0
+; CHECK-NEXT:    xsmaddasp 1, 3, 4
+; CHECK-NEXT:    xsdivsp 1, 0, 1
 ; CHECK-NEXT:    blr
   %mul1 = fmul contract float %f1, %f2
   %mul2 = fmul float %f3, %f4
   %add = fadd contract float %mul1, %mul2
   %second_use_of_mul1 = fdiv float %mul1, %add
   ret float %second_use_of_mul1
 }

test/CodeGen/PowerPC/fmf-propagation.ll

 ; The run with the global unsafe param tests the pre-FMF behavior using regular instructions/nodes.
 
 declare float @llvm.fma.f32(float, float, float)
 declare float @llvm.sqrt.f32(float)
 
 ; X * Y + Z --> fma(X, Y, Z)
 
 ; FMFDEBUG-LABEL: Optimized lowered selection DAG: %bb.0 'fmul_fadd_contract1:'
-; FMFDEBUG:         fmul {{t[0-9]+}}, {{t[0-9]+}}
-; FMFDEBUG:         fadd contract {{t[0-9]+}}, {{t[0-9]+}}
+; FMFDEBUG:         fma contract {{t[0-9]+}}, {{t[0-9]+}}, {{t[0-9]+}}
 ; FMFDEBUG:       Type-legalized selection DAG: %bb.0 'fmul_fadd_contract1:'
 
 define float @fmul_fadd_contract1(float %x, float %y, float %z) {
 ; FMF-LABEL: fmul_fadd_contract1:
 ; FMF:       # %bb.0:
-; FMF-NEXT:    xsmulsp 0, 1, 2
-; FMF-NEXT:    xsaddsp 1, 0, 3
+; FMF-NEXT:    xsmaddasp 3, 1, 2
+; FMF-NEXT:    fmr 1, 3
 ; FMF-NEXT:    blr
 ;
 ; GLOBAL-LABEL: fmul_fadd_contract1:
 ; GLOBAL:       # %bb.0:
 ; GLOBAL-NEXT:    xsmaddasp 3, 1, 2
 ; GLOBAL-NEXT:    fmr 1, 3
 ; GLOBAL-NEXT:    blr
   %mul = fmul float %x, %y
; GLOBAL-NEXT:    blr
   %mul = fmul contract float %x, %y
   %add = fadd contract float %mul, %z
   ret float %add
 }
 
 ; Reassociation implies that FMA contraction is allowed.
 
 ; FMFDEBUG-LABEL: Optimized lowered selection DAG: %bb.0 'fmul_fadd_reassoc1:'
-; FMFDEBUG:         fmul {{t[0-9]+}}, {{t[0-9]+}}
-; FMFDEBUG:         fadd reassoc {{t[0-9]+}}, {{t[0-9]+}}
+; FMFDEBUG:         fma reassoc {{t[0-9]+}}, {{t[0-9]+}}, {{t[0-9]+}}
 ; FMFDEBUG:       Type-legalized selection DAG: %bb.0 'fmul_fadd_reassoc1:'
 
 define float @fmul_fadd_reassoc1(float %x, float %y, float %z) {
 ; FMF-LABEL: fmul_fadd_reassoc1:
 ; FMF:       # %bb.0:
-; FMF-NEXT:    xsmulsp 0, 1, 2
-; FMF-NEXT:    xsaddsp 1, 0, 3
+; FMF-NEXT:    xsmaddasp 3, 1, 2
+; FMF-NEXT:    fmr 1, 3
 ; FMF-NEXT:    blr
 ;
 ; GLOBAL-LABEL: fmul_fadd_reassoc1:
 ; GLOBAL:       # %bb.0:
 ; GLOBAL-NEXT:    xsmaddasp 3, 1, 2
 ; GLOBAL-NEXT:    fmr 1, 3
 ; GLOBAL-NEXT:    blr
   %mul = fmul float %x, %y
; GLOBAL-NEXT:    blr
   %add = fadd fast float %mul, %z
   ret float %add
 }
 
 ; fma(X, 7.0, X * 42.0) --> X * 49.0
 ; This is the minimum FMF needed for this transform - the FMA allows reassociation.
 
 ; FMFDEBUG-LABEL: Optimized lowered selection DAG: %bb.0 'fmul_fma_reassoc1:'
-; FMFDEBUG:         fma reassoc {{t[0-9]+}}
+; FMFDEBUG:         fmul reassoc {{t[0-9]+}}, 
 ; FMFDEBUG:       Type-legalized selection DAG: %bb.0 'fmul_fma_reassoc1:'
 
 ; GLOBALDEBUG-LABEL: Optimized lowered selection DAG: %bb.0 'fmul_fma_reassoc1:'
 ; GLOBALDEBUG:         fmul reassoc {{t[0-9]+}}
 ; GLOBALDEBUG:       Type-legalized selection DAG: %bb.0 'fmul_fma_reassoc1:'
 
 define float @fmul_fma_reassoc1(float %x) {
 ; FMF-LABEL: fmul_fma_reassoc1:
 ; FMF:       # %bb.0:
 ; FMF-NEXT:    addis 3, 2, .LCPI6_0@toc@ha
 ; FMF-NEXT:    addi 3, 3, .LCPI6_0@toc@l
 ; FMF-NEXT:    lfsx 0, 0, 3
-; FMF-NEXT:    addis 3, 2, .LCPI6_1@toc@ha
-; FMF-NEXT:    addi 3, 3, .LCPI6_1@toc@l
-; FMF-NEXT:    lfsx 2, 0, 3
-; FMF-NEXT:    xsmulsp 0, 1, 0
-; FMF-NEXT:    xsmaddasp 0, 1, 2
-; FMF-NEXT:    fmr 1, 0
+; FMF-NEXT:    xsmulsp 1, 1, 0
 ; FMF-NEXT:    blr
 ;
 ; GLOBAL-LABEL: fmul_fma_reassoc1:
 ; GLOBAL:       # %bb.0:
 ; GLOBAL-NEXT:    addis 3, 2, .LCPI6_0@toc@ha
 ; GLOBAL-NEXT:    addi 3, 3, .LCPI6_0@toc@l
 ; GLOBAL-NEXT:    lfsx 0, 0, 3
 ; GLOBAL-NEXT:    xsmulsp 1, 1, 0
 ; GLOBAL-NEXT:    blr
   %mul = fmul float %x, 42.0
   %fma = call reassoc float @llvm.fma.f32(float %x, float 7.0, float %mul)
   ret float %fma
 }
 
 ; This shouldn't change anything - the intermediate fmul result is now also flagged.
 
 ; FMFDEBUG-LABEL: Optimized lowered selection DAG: %bb.0 'fmul_fma_reassoc2:'
 ; FMFDEBUG:         fmul reassoc {{t[0-9]+}}
-; FMFDEBUG:         fma reassoc {{t[0-9]+}}
 ; FMFDEBUG:       Type-legalized selection DAG: %bb.0 'fmul_fma_reassoc2:'
 
 ; GLOBALDEBUG-LABEL: Optimized lowered selection DAG: %bb.0 'fmul_fma_reassoc2:'
 ; GLOBALDEBUG:         fmul reassoc {{t[0-9]+}}
 ; GLOBALDEBUG:       Type-legalized selection DAG: %bb.0 'fmul_fma_reassoc2:'
 
 define float @fmul_fma_reassoc2(float %x) {
 ; FMF-LABEL: fmul_fma_reassoc2:
 ; FMF:       # %bb.0:
 ; FMF-NEXT:    addis 3, 2, .LCPI7_0@toc@ha
 ; FMF-NEXT:    addi 3, 3, .LCPI7_0@toc@l
 ; FMF-NEXT:    lfsx 0, 0, 3
-; FMF-NEXT:    addis 3, 2, .LCPI7_1@toc@ha
-; FMF-NEXT:    addi 3, 3, .LCPI7_1@toc@l
-; FMF-NEXT:    lfsx 2, 0, 3
-; FMF-NEXT:    xsmulsp 0, 1, 0
-; FMF-NEXT:    xsmaddasp 0, 1, 2
-; FMF-NEXT:    fmr 1, 0
+; FMF-NEXT:    xsmulsp 1, 1, 0
 ; FMF-NEXT:    blr
 ;
 ; GLOBAL-LABEL: fmul_fma_reassoc2:
 ; GLOBAL:       # %bb.0:
 ; GLOBAL-NEXT:    addis 3, 2, .LCPI7_0@toc@ha
 ; GLOBAL-NEXT:    addi 3, 3, .LCPI7_0@toc@l
 ; GLOBAL-NEXT:    lfsx 0, 0, 3
 ; GLOBAL-NEXT:    xsmulsp 1, 1, 0
 ; GLOBAL-NEXT:    blr
   %mul = fmul reassoc float %x, 42.0
   %fma = call reassoc float @llvm.fma.f32(float %x, float 7.0, float %mul)
   ret float %fma
 }
 
 ; The FMA is now fully 'fast'. This implies that reassociation is allowed.
 
 ; FMFDEBUG-LABEL: Optimized lowered selection DAG: %bb.0 'fmul_fma_fast1:'
-; FMFDEBUG:         fma nnan ninf nsz arcp contract afn reassoc {{t[0-9]+}}
+; FMFDEBUG:         fmul nnan ninf nsz arcp contract afn reassoc {{t[0-9]+}}
 ; FMFDEBUG:       Type-legalized selection DAG: %bb.0 'fmul_fma_fast1:'
 
 ; GLOBALDEBUG-LABEL: Optimized lowered selection DAG: %bb.0 'fmul_fma_fast1:'
 ; GLOBALDEBUG:         fmul nnan ninf nsz arcp contract afn reassoc {{t[0-9]+}}
 ; GLOBALDEBUG:       Type-legalized selection DAG: %bb.0 'fmul_fma_fast1:'
 
 define float @fmul_fma_fast1(float %x) {
 ; FMF-LABEL: fmul_fma_fast1:
 ; FMF:       # %bb.0:
 ; FMF-NEXT:    addis 3, 2, .LCPI8_0@toc@ha
 ; FMF-NEXT:    addi 3, 3, .LCPI8_0@toc@l
 ; FMF-NEXT:    lfsx 0, 0, 3
-; FMF-NEXT:    addis 3, 2, .LCPI8_1@toc@ha
-; FMF-NEXT:    addi 3, 3, .LCPI8_1@toc@l
-; FMF-NEXT:    lfsx 2, 0, 3
-; FMF-NEXT:    xsmulsp 0, 1, 0
-; FMF-NEXT:    xsmaddasp 0, 1, 2
-; FMF-NEXT:    fmr 1, 0
+; FMF-NEXT:    xsmulsp 1, 1, 0
 ; FMF-NEXT:    blr
 ;
 ; GLOBAL-LABEL: fmul_fma_fast1:
 ; GLOBAL:       # %bb.0:
 ; GLOBAL-NEXT:    addis 3, 2, .LCPI8_0@toc@ha
 ; GLOBAL-NEXT:    addi 3, 3, .LCPI8_0@toc@l
 ; GLOBAL-NEXT:    lfsx 0, 0, 3
 ; GLOBAL-NEXT:    xsmulsp 1, 1, 0
 ; GLOBAL-NEXT:    blr
   %mul = fmul float %x, 42.0
   %fma = call fast float @llvm.fma.f32(float %x, float 7.0, float %mul)
   ret float %fma
 }
 
 ; This shouldn't change anything - the intermediate fmul result is now also flagged.
 
 ; FMFDEBUG-LABEL: Optimized lowered selection DAG: %bb.0 'fmul_fma_fast2:'
 ; FMFDEBUG:         fmul nnan ninf nsz arcp contract afn reassoc {{t[0-9]+}}
-; FMFDEBUG:         fma nnan ninf nsz arcp contract afn reassoc {{t[0-9]+}}
 ; FMFDEBUG:       Type-legalized selection DAG: %bb.0 'fmul_fma_fast2:'
 
 ; GLOBALDEBUG-LABEL: Optimized lowered selection DAG: %bb.0 'fmul_fma_fast2:'
 ; GLOBALDEBUG:         fmul nnan ninf nsz arcp contract afn reassoc {{t[0-9]+}}
 ; GLOBALDEBUG:       Type-legalized selection DAG: %bb.0 'fmul_fma_fast2:'
 
 define float @fmul_fma_fast2(float %x) {
 ; FMF-LABEL: fmul_fma_fast2:
 ; FMF:       # %bb.0:
 ; FMF-NEXT:    addis 3, 2, .LCPI9_0@toc@ha
 ; FMF-NEXT:    addi 3, 3, .LCPI9_0@toc@l
 ; FMF-NEXT:    lfsx 0, 0, 3
-; FMF-NEXT:    addis 3, 2, .LCPI9_1@toc@ha
-; FMF-NEXT:    addi 3, 3, .LCPI9_1@toc@l
-; FMF-NEXT:    lfsx 2, 0, 3
-; FMF-NEXT:    xsmulsp 0, 1, 0
-; FMF-NEXT:    xsmaddasp 0, 1, 2
-; FMF-NEXT:    fmr 1, 0
+; FMF-NEXT:    xsmulsp 1, 1, 0
 ; FMF-NEXT:    blr
 ;
 ; GLOBAL-LABEL: fmul_fma_fast2:
 ; GLOBAL:       # %bb.0:
 ; GLOBAL-NEXT:    addis 3, 2, .LCPI9_0@toc@ha
 ; GLOBAL-NEXT:    addi 3, 3, .LCPI9_0@toc@l
 ; GLOBAL-NEXT:    lfsx 0, 0, 3
 ; GLOBAL-NEXT:    xsmulsp 1, 1, 0

 ; FMF-NEXT:       xsmulsp 4, 3, 3
 ; FMF-NEXT:       xssubsp 2, 2, 1
 ; FMF-NEXT:       xsmulsp 2, 2, 4
 ; FMF-NEXT:       xssubsp 0, 0, 2
 ; FMF-NEXT:       xsmulsp 0, 3, 0
 ; FMF-NEXT:       xsmulsp 0, 0, 1
 ; FMF-NEXT:     .LBB10_2:
 ; FMF-NEXT:       fmr 1, 0
 ; FMF-NEXT:       blr
 ;
 ; GLOBAL-LABEL: sqrt_afn:
 ; GLOBAL:       # %bb.0:
 ; GLOBAL-NEXT:    xxlxor 0, 0, 0
 ; GLOBAL-NEXT:    fcmpu 0, 1, 0
 ; GLOBAL-NEXT:    beq 0, .LBB10_2
 ; GLOBAL-NEXT:  # %bb.1:
 ; GLOBAL-NEXT:    xsrsqrtesp 2, 1

test/CodeGen/X86/fmf-flags_fma.ll

+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mattr=+avx2,+fma -mtriple=x86_64-apple-macosx10.8.0 | FileCheck %s -check-prefix=X64
+
+declare float @llvm.fma.f32(float %a, float %b, float %c);
+
+define float @fast_fmuladd_rep1(float %a , float %b , float %c) {
+; X64-LABEL: fast_fmuladd_rep1:
+; X64:       # %bb.0:
+; X64-NEXT:    vfmadd213ss %xmm2, %xmm1, %xmm0
+  %mul.1 = fmul fast float %a, %b
+  %res = fadd fast float %mul.1, %c
+  ret float %res
+}
+
+define float @fast_fmuladd_rep2(float %a , float %b , float %c) {
+; X64-LABEL: fast_fmuladd_rep2:
+; X64:       # %bb.0:
+; X64-NEXT:    vfmadd213ss %xmm2, %xmm1, %xmm0
+  %mul.1 = fmul fast float %a, %b
+  %res = fadd fast float %c, %mul.1
+  ret float %res
+}
+
+define float @fast_fmuladd_rep3(half %a , half %b , float %c) {
+; X64-LABEL: fast_fmuladd_rep3:
+; X64:       # %bb.0:
+; X64:         vfmadd213ss {{[0-9]+}}(%rsp), %xmm1, %xmm0 
+  %mul.1 = fmul fast half %a, %b
+  %ext = fpext half %mul.1 to float
+  %res = fadd fast float %ext, %c
+  ret float %res
+}
+
+define float @fast_fmuladd_rep4(half %a , half %b , float %c) {
+; X64-LABEL: fast_fmuladd_rep4:
+; X64:       # %bb.0:
+; X64:         vfmadd213ss {{[0-9]+}}(%rsp), %xmm1, %xmm0 
+  %mul.1 = fmul fast half %a, %b
+  %ext = fpext half %mul.1 to float
+  %res = fadd fast float %c, %ext
+  ret float %res
+}