[x86] Minor refactoring of X86TargetLowering::EmitInstrWithCustomInserter:

[aivchenk]

Summary

Move the definitions of three variables out of the switch.

[qcolombet]

+llvm-commits

[qcolombet]

LGTM

lib/Target/X86/X86ISelLowering.cpp

X86TargetLowering::EmitSjLjDispatchBlock(MachineInstr &MI,
   // The instruction is gone now.
   MI.eraseFromParent();
   return BB;
 }
 
 MachineBasicBlock *
 X86TargetLowering::EmitInstrWithCustomInserter(MachineInstr &MI,
                                                MachineBasicBlock *BB) const {
+  MachineFunction *MF = BB->getParent();
+  const TargetInstrInfo *TII = Subtarget.getInstrInfo();
+  DebugLoc DL = MI.getDebugLoc();
+
   switch (MI.getOpcode()) {
   default: llvm_unreachable("Unexpected instr type to insert");
   case X86::TAILJMPd64:
   case X86::TAILJMPr64:
   case X86::TAILJMPm64:
   case X86::TAILJMPr64_REX:
   case X86::TAILJMPm64_REX:
     llvm_unreachable("TAILJMP64 would not be touched here.");
X86TargetLowering::EmitInstrWithCustomInserter(MachineInstr &MI,
   case X86::CMOV_V8I1:
   case X86::CMOV_V16I1:
   case X86::CMOV_V32I1:
   case X86::CMOV_V64I1:
     return EmitLoweredSelect(MI, BB);
 
   case X86::RDFLAGS32:
   case X86::RDFLAGS64: {
-    DebugLoc DL = MI.getDebugLoc();
-    const TargetInstrInfo *TII = Subtarget.getInstrInfo();
     unsigned PushF =
         MI.getOpcode() == X86::RDFLAGS32 ? X86::PUSHF32 : X86::PUSHF64;
     unsigned Pop = MI.getOpcode() == X86::RDFLAGS32 ? X86::POP32r : X86::POP64r;
     MachineInstr *Push = BuildMI(*BB, MI, DL, TII->get(PushF));
     // Permit reads of the FLAGS register without it being defined.
     // This intrinsic exists to read external processor state in flags, such as
     // the trap flag, interrupt flag, and direction flag, none of which are
     // modeled by the backend.
     Push->getOperand(2).setIsUndef();
     BuildMI(*BB, MI, DL, TII->get(Pop), MI.getOperand(0).getReg());
 
     MI.eraseFromParent(); // The pseudo is gone now.
     return BB;
   }
 
   case X86::WRFLAGS32:
   case X86::WRFLAGS64: {
-    DebugLoc DL = MI.getDebugLoc();
-    const TargetInstrInfo *TII = Subtarget.getInstrInfo();
     unsigned Push =
         MI.getOpcode() == X86::WRFLAGS32 ? X86::PUSH32r : X86::PUSH64r;
     unsigned PopF =
         MI.getOpcode() == X86::WRFLAGS32 ? X86::POPF32 : X86::POPF64;
     BuildMI(*BB, MI, DL, TII->get(Push)).addReg(MI.getOperand(0).getReg());
     BuildMI(*BB, MI, DL, TII->get(PopF));
 
     MI.eraseFromParent(); // The pseudo is gone now.
     return BB;
   }
 
   case X86::RELEASE_FADD32mr:
   case X86::RELEASE_FADD64mr:
     return EmitLoweredAtomicFP(MI, BB);
 
   case X86::FP32_TO_INT16_IN_MEM:
   case X86::FP32_TO_INT32_IN_MEM:
   case X86::FP32_TO_INT64_IN_MEM:
   case X86::FP64_TO_INT16_IN_MEM:
   case X86::FP64_TO_INT32_IN_MEM:
   case X86::FP64_TO_INT64_IN_MEM:
   case X86::FP80_TO_INT16_IN_MEM:
   case X86::FP80_TO_INT32_IN_MEM:
   case X86::FP80_TO_INT64_IN_MEM: {
-    MachineFunction *F = BB->getParent();
-    const TargetInstrInfo *TII = Subtarget.getInstrInfo();
-    DebugLoc DL = MI.getDebugLoc();
-
     // Change the floating point control register to use "round towards zero"
     // mode when truncating to an integer value.
-    int CWFrameIdx = F->getFrameInfo().CreateStackObject(2, 2, false);
+    int CWFrameIdx = MF->getFrameInfo().CreateStackObject(2, 2, false);
     addFrameReference(BuildMI(*BB, MI, DL,
                               TII->get(X86::FNSTCW16m)), CWFrameIdx);
 
     // Load the old value of the high byte of the control word...
     unsigned OldCW =
-      F->getRegInfo().createVirtualRegister(&X86::GR16RegClass);
+      MF->getRegInfo().createVirtualRegister(&X86::GR16RegClass);
     addFrameReference(BuildMI(*BB, MI, DL, TII->get(X86::MOV16rm), OldCW),
                       CWFrameIdx);
 
     // Set the high part to be round to zero...
     addFrameReference(BuildMI(*BB, MI, DL, TII->get(X86::MOV16mi)), CWFrameIdx)
       .addImm(0xC7F);
 
     // Reload the modified control word now...