[llvm] [PowerPC] Do not generate `isel` instruction if target doesn't have this instruction (PR #72845)

[Qiu Chaofan via llvm-commits]

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@@ -12701,9 +12702,10 @@ PPCTargetLowering::EmitInstrWithCustomInserter(MachineInstr &MI,
   MachineFunction *F = BB->getParent();
   MachineRegisterInfo &MRI = F->getRegInfo();
 
-  if (MI.getOpcode() == PPC::SELECT_CC_I4 ||
-      MI.getOpcode() == PPC::SELECT_CC_I8 || MI.getOpcode() == PPC::SELECT_I4 ||
-      MI.getOpcode() == PPC::SELECT_I8) {
+  if (HasISEL &&
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ecnelises wrote:

Using `Subtarget.hasISEL()` is good here if it's been used only once.

https://github.com/llvm/llvm-project/pull/72845