[llvm] [X86][GlobalISel] Support fp80 for G_FPTRUNC and G_FPEXT (PR #141611)

[Matt Arsenault via llvm-commits]

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@@ -874,28 +871,128 @@ bool X86LegalizerInfo::legalizeGETROUNDING(MachineInstr &MI,
   return true;
 }
 
-bool X86LegalizerInfo::legalizeFPExtAndTrunc(MachineInstr &MI,
-                                             MachineRegisterInfo &MRI,
-                                             LegalizerHelper &Helper) const {
-  assert((MI.getOpcode() == TargetOpcode::G_FPEXT ||
-          MI.getOpcode() == TargetOpcode::G_FPTRUNC) &&
-         "Only G_FPEXT and G_FPTRUNC are expected");
-  auto [DstReg, DstTy, SrcReg, SrcTy] = MI.getFirst2RegLLTs();
-  MachinePointerInfo PtrInfo;
-  LLT StackTy = MI.getOpcode() == TargetOpcode::G_FPEXT ? SrcTy : DstTy;
-  Align StackTyAlign = Helper.getStackTemporaryAlignment(StackTy);
-  auto StackTemp = Helper.createStackTemporary(StackTy.getSizeInBytes(),
-                                               StackTyAlign, PtrInfo);
-
+bool X86LegalizerInfo::legalizeSETROUNDING(MachineInstr &MI,
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arsenm wrote:

Can you rebase to drop this unrelated stuff that already was submitted 

https://github.com/llvm/llvm-project/pull/141611