diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp --- a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp @@ -2258,15 +2258,24 @@ return II; } - // fma x, 1, z -> fadd x, z - if (match(Src1, m_FPOne())) { - auto *FAdd = BinaryOperator::CreateFAdd(Src0, II->getArgOperand(2)); + // Try to simplify the underlying FMul. + if (Value *V = SimplifyFMulInst(II->getArgOperand(0), II->getArgOperand(1), + II->getFastMathFlags(), + SQ.getWithInstruction(II))) { + if (match(V, m_FMul(m_Value(X), m_Value(Y)))) { + II->setArgOperand(0, X); + II->setArgOperand(1, Y); + return II; + } + + auto *FAdd = BinaryOperator::CreateFAdd(V, II->getArgOperand(2)); FAdd->copyFastMathFlags(II); return FAdd; } break; } + case Intrinsic::fabs: { Value *Cond; Constant *LHS, *RHS; diff --git a/llvm/test/Transforms/InstCombine/fma.ll b/llvm/test/Transforms/InstCombine/fma.ll --- a/llvm/test/Transforms/InstCombine/fma.ll +++ b/llvm/test/Transforms/InstCombine/fma.ll @@ -372,8 +372,7 @@ define <2 x double> @fmuladd_a_0_b(<2 x double> %a, <2 x double> %b) { ; CHECK-LABEL: @fmuladd_a_0_b( ; CHECK-NEXT: entry: -; CHECK-NEXT: [[RES:%.*]] = call nnan nsz <2 x double> @llvm.fmuladd.v2f64(<2 x double> [[A:%.*]], <2 x double> zeroinitializer, <2 x double> [[B:%.*]]) -; CHECK-NEXT: ret <2 x double> [[RES]] +; CHECK-NEXT: ret <2 x double> [[B:%.*]] ; entry: %res = call nnan nsz <2 x double> @llvm.fmuladd.v2f64(<2 x double> %a, <2 x double> zeroinitializer, <2 x double> %b) @@ -383,8 +382,7 @@ define <2 x double> @fmuladd_0_a_b(<2 x double> %a, <2 x double> %b) { ; CHECK-LABEL: @fmuladd_0_a_b( ; CHECK-NEXT: entry: -; CHECK-NEXT: [[RES:%.*]] = call nnan nsz <2 x double> @llvm.fmuladd.v2f64(<2 x double> [[A:%.*]], <2 x double> zeroinitializer, <2 x double> [[B:%.*]]) -; CHECK-NEXT: ret <2 x double> [[RES]] +; CHECK-NEXT: ret <2 x double> [[B:%.*]] ; entry: %res = call nnan nsz <2 x double> @llvm.fmuladd.v2f64(<2 x double> zeroinitializer, <2 x double> %a, <2 x double> %b) @@ -407,8 +405,7 @@ define <2 x double> @fma_a_0_b(<2 x double> %a, <2 x double> %b) { ; CHECK-LABEL: @fma_a_0_b( ; CHECK-NEXT: entry: -; CHECK-NEXT: [[RES:%.*]] = call nnan nsz <2 x double> @llvm.fma.v2f64(<2 x double> [[A:%.*]], <2 x double> zeroinitializer, <2 x double> [[B:%.*]]) -; CHECK-NEXT: ret <2 x double> [[RES]] +; CHECK-NEXT: ret <2 x double> [[B:%.*]] ; entry: %res = call nnan nsz <2 x double> @llvm.fma.v2f64(<2 x double> %a, <2 x double> zeroinitializer, <2 x double> %b) @@ -418,8 +415,7 @@ define <2 x double> @fma_0_a_b(<2 x double> %a, <2 x double> %b) { ; CHECK-LABEL: @fma_0_a_b( ; CHECK-NEXT: entry: -; CHECK-NEXT: [[RES:%.*]] = call nnan nsz <2 x double> @llvm.fma.v2f64(<2 x double> [[A:%.*]], <2 x double> zeroinitializer, <2 x double> [[B:%.*]]) -; CHECK-NEXT: ret <2 x double> [[RES]] +; CHECK-NEXT: ret <2 x double> [[B:%.*]] ; entry: %res = call nnan nsz <2 x double> @llvm.fma.v2f64(<2 x double> zeroinitializer, <2 x double> %a, <2 x double> %b) @@ -440,8 +436,7 @@ define <2 x double> @fma_sqrt(<2 x double> %a, <2 x double> %b) { ; CHECK-LABEL: @fma_sqrt( ; CHECK-NEXT: entry: -; CHECK-NEXT: [[SQRT:%.*]] = call fast <2 x double> @llvm.sqrt.v2f64(<2 x double> [[A:%.*]]) -; CHECK-NEXT: [[RES:%.*]] = call fast <2 x double> @llvm.fma.v2f64(<2 x double> [[SQRT]], <2 x double> [[SQRT]], <2 x double> [[B:%.*]]) +; CHECK-NEXT: [[RES:%.*]] = fadd fast <2 x double> [[A:%.*]], [[B:%.*]] ; CHECK-NEXT: ret <2 x double> [[RES]] ; entry: