PowerPC: Don't hoist float multiply + add to fused operation on SPE

SPE doesn't have a fmadd instruction, so don't bother hoisting a multiply and add sequence to this, as it'd become just a library call. Hoisting happens too late for the CTR usability test to veto using the CTR in a loop, and results in an assert "Invalid PPC CTR loop!".
llvm · Aug 10, 2022 · f43b228 · f43b228
1 parent 30abc1a
commit f43b228
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diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -16676,6 +16676,8 @@ bool PPCTargetLowering::isFMAFasterThanFMulAndFAdd(const MachineFunction &MF,
 
 bool PPCTargetLowering::isFMAFasterThanFMulAndFAdd(const Function &F,
                                                    Type *Ty) const {
+  if (Subtarget.hasSPE())
+    return false;
   switch (Ty->getScalarType()->getTypeID()) {
   case Type::FloatTyID:
   case Type::DoubleTyID: