refactor select 'sched insertion' out to its own method.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80764 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/X86/X86ISelLowering.cpp

@@ -7702,11 +7702,67 @@ X86TargetLowering::EmitVAStartSaveXMMRegsWithCustomInserter(
   return EndMBB;
 }
 
+MachineBasicBlock *
+X86TargetLowering::EmitLoweredSelect(MachineInstr *MI,
+                                     MachineBasicBlock *BB) const {
+  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
+  DebugLoc DL = MI->getDebugLoc();
+  
+  // To "insert" a SELECT_CC instruction, we actually have to insert the
+  // diamond control-flow pattern.  The incoming instruction knows the
+  // destination vreg to set, the condition code register to branch on, the
+  // true/false values to select between, and a branch opcode to use.
+  const BasicBlock *LLVM_BB = BB->getBasicBlock();
+  MachineFunction::iterator It = BB;
+  ++It;
+  
+  //  thisMBB:
+  //  ...
+  //   TrueVal = ...
+  //   cmpTY ccX, r1, r2
+  //   bCC copy1MBB
+  //   fallthrough --> copy0MBB
+  MachineBasicBlock *thisMBB = BB;
+  MachineFunction *F = BB->getParent();
+  MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
+  MachineBasicBlock *sinkMBB = F->CreateMachineBasicBlock(LLVM_BB);
+  unsigned Opc =
+    X86::GetCondBranchFromCond((X86::CondCode)MI->getOperand(3).getImm());
+  BuildMI(BB, DL, TII->get(Opc)).addMBB(sinkMBB);
+  F->insert(It, copy0MBB);
+  F->insert(It, sinkMBB);
+  // Update machine-CFG edges by transferring all successors of the current
+  // block to the new block which will contain the Phi node for the select.
+  sinkMBB->transferSuccessors(BB);
+  
+  // Add the true and fallthrough blocks as its successors.
+  BB->addSuccessor(copy0MBB);
+  BB->addSuccessor(sinkMBB);
+  
+  //  copy0MBB:
+  //   %FalseValue = ...
+  //   # fallthrough to sinkMBB
+  BB = copy0MBB;
+  
+  // Update machine-CFG edges
+  BB->addSuccessor(sinkMBB);
+  
+  //  sinkMBB:
+  //   %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
+  //  ...
+  BB = sinkMBB;
+  BuildMI(BB, DL, TII->get(X86::PHI), MI->getOperand(0).getReg())
+    .addReg(MI->getOperand(1).getReg()).addMBB(copy0MBB)
+    .addReg(MI->getOperand(2).getReg()).addMBB(thisMBB);
+
+  F->DeleteMachineInstr(MI);   // The pseudo instruction is gone now.
+  return BB;
+}
+
+
 MachineBasicBlock *
 X86TargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
                                                MachineBasicBlock *BB) const {
-  DebugLoc dl = MI->getDebugLoc();
-  const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
   switch (MI->getOpcode()) {
   default: assert(false && "Unexpected instr type to insert");
   case X86::CMOV_GR8:
@@ -7715,57 +7771,8 @@ X86TargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
   case X86::CMOV_FR64:
   case X86::CMOV_V4F32:
   case X86::CMOV_V2F64:
-  case X86::CMOV_V2I64: {
+  case X86::CMOV_V2I64:
-    // To "insert" a SELECT_CC instruction, we actually have to insert the
+    return EmitLoweredSelect(MI, BB);
-    // diamond control-flow pattern.  The incoming instruction knows the
-    // destination vreg to set, the condition code register to branch on, the
-    // true/false values to select between, and a branch opcode to use.
-    const BasicBlock *LLVM_BB = BB->getBasicBlock();
-    MachineFunction::iterator It = BB;
-    ++It;
-
-    //  thisMBB:
-    //  ...
-    //   TrueVal = ...
-    //   cmpTY ccX, r1, r2
-    //   bCC copy1MBB
-    //   fallthrough --> copy0MBB
-    MachineBasicBlock *thisMBB = BB;
-    MachineFunction *F = BB->getParent();
-    MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
-    MachineBasicBlock *sinkMBB = F->CreateMachineBasicBlock(LLVM_BB);
-    unsigned Opc =
-      X86::GetCondBranchFromCond((X86::CondCode)MI->getOperand(3).getImm());
-    BuildMI(BB, dl, TII->get(Opc)).addMBB(sinkMBB);
-    F->insert(It, copy0MBB);
-    F->insert(It, sinkMBB);
-    // Update machine-CFG edges by transferring all successors of the current
-    // block to the new block which will contain the Phi node for the select.
-    sinkMBB->transferSuccessors(BB);
-
-    // Add the true and fallthrough blocks as its successors.
-    BB->addSuccessor(copy0MBB);
-    BB->addSuccessor(sinkMBB);
-
-    //  copy0MBB:
-    //   %FalseValue = ...
-    //   # fallthrough to sinkMBB
-    BB = copy0MBB;
-
-    // Update machine-CFG edges
-    BB->addSuccessor(sinkMBB);
-
-    //  sinkMBB:
-    //   %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
-    //  ...
-    BB = sinkMBB;
-    BuildMI(BB, dl, TII->get(X86::PHI), MI->getOperand(0).getReg())
-      .addReg(MI->getOperand(1).getReg()).addMBB(copy0MBB)
-      .addReg(MI->getOperand(2).getReg()).addMBB(thisMBB);
-
-    F->DeleteMachineInstr(MI);   // The pseudo instruction is gone now.
-    return BB;
-  }
 
   case X86::FP32_TO_INT16_IN_MEM:
   case X86::FP32_TO_INT32_IN_MEM:
@@ -7776,27 +7783,30 @@ X86TargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
   case X86::FP80_TO_INT16_IN_MEM:
   case X86::FP80_TO_INT32_IN_MEM:
   case X86::FP80_TO_INT64_IN_MEM: {
+    const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
+    DebugLoc DL = MI->getDebugLoc();
+
     // Change the floating point control register to use "round towards zero"
     // mode when truncating to an integer value.
     MachineFunction *F = BB->getParent();
     int CWFrameIdx = F->getFrameInfo()->CreateStackObject(2, 2);
-    addFrameReference(BuildMI(BB, dl, TII->get(X86::FNSTCW16m)), CWFrameIdx);
+    addFrameReference(BuildMI(BB, DL, TII->get(X86::FNSTCW16m)), CWFrameIdx);
 
     // Load the old value of the high byte of the control word...
     unsigned OldCW =
       F->getRegInfo().createVirtualRegister(X86::GR16RegisterClass);
-    addFrameReference(BuildMI(BB, dl, TII->get(X86::MOV16rm), OldCW),
+    addFrameReference(BuildMI(BB, DL, TII->get(X86::MOV16rm), OldCW),
                       CWFrameIdx);
 
     // Set the high part to be round to zero...
-    addFrameReference(BuildMI(BB, dl, TII->get(X86::MOV16mi)), CWFrameIdx)
+    addFrameReference(BuildMI(BB, DL, TII->get(X86::MOV16mi)), CWFrameIdx)
       .addImm(0xC7F);
 
     // Reload the modified control word now...
-    addFrameReference(BuildMI(BB, dl, TII->get(X86::FLDCW16m)), CWFrameIdx);
+    addFrameReference(BuildMI(BB, DL, TII->get(X86::FLDCW16m)), CWFrameIdx);
 
     // Restore the memory image of control word to original value
-    addFrameReference(BuildMI(BB, dl, TII->get(X86::MOV16mr)), CWFrameIdx)
+    addFrameReference(BuildMI(BB, DL, TII->get(X86::MOV16mr)), CWFrameIdx)
       .addReg(OldCW);
 
     // Get the X86 opcode to use.
@@ -7835,11 +7845,11 @@ X86TargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
     } else {
       AM.Disp = Op.getImm();
     }
-    addFullAddress(BuildMI(BB, dl, TII->get(Opc)), AM)
+    addFullAddress(BuildMI(BB, DL, TII->get(Opc)), AM)
                       .addReg(MI->getOperand(X86AddrNumOperands).getReg());
 
     // Reload the original control word now.
-    addFrameReference(BuildMI(BB, dl, TII->get(X86::FLDCW16m)), CWFrameIdx);
+    addFrameReference(BuildMI(BB, DL, TII->get(X86::FLDCW16m)), CWFrameIdx);
 
     F->DeleteMachineInstr(MI);   // The pseudo instruction is gone now.
     return BB;

lib/Target/X86/X86ISelLowering.h

@@ -738,6 +738,9 @@ namespace llvm {
                                                    MachineInstr *BInstr,
                                                    MachineBasicBlock *BB) const;
 
+    MachineBasicBlock *EmitLoweredSelect(MachineInstr *I,
+                                         MachineBasicBlock *BB) const;
+    
     /// Emit nodes that will be selected as "test Op0,Op0", or something
     /// equivalent, for use with the given x86 condition code.
     SDValue EmitTest(SDValue Op0, unsigned X86CC, SelectionDAG &DAG);