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[oota-llvm.git] / lib / CodeGen / LowerSubregs.cpp

diff --git a/lib/CodeGen/LowerSubregs.cpp b/lib/CodeGen/LowerSubregs.cpp
index eccae52fbcd03273493a038dd778968db1e40828..ad1c537c1911a357d6b203d8727d8378109029a9 100644 (file)
--- a/lib/CodeGen/LowerSubregs.cpp
+++ b/lib/CodeGen/LowerSubregs.cpp
@@ -36,7 +36,7 @@ namespace {
 
   public:
     static char ID; // Pass identification, replacement for typeid
-    LowerSubregsInstructionPass() : MachineFunctionPass(&ID) {}
+    LowerSubregsInstructionPass() : MachineFunctionPass(ID) {}
     
     const char *getPassName() const {
       return "Subregister lowering instruction pass";
@@ -53,15 +53,11 @@ namespace {
     bool runOnMachineFunction(MachineFunction&);
 
   private:
-    bool LowerExtract(MachineInstr *MI);
     bool LowerSubregToReg(MachineInstr *MI);
     bool LowerCopy(MachineInstr *MI);
 
     void TransferDeadFlag(MachineInstr *MI, unsigned DstReg,
                           const TargetRegisterInfo *TRI);
-    void TransferKillFlag(MachineInstr *MI, unsigned SrcReg,
-                          const TargetRegisterInfo *TRI,
-                          bool AddIfNotFound = false);
     void TransferImplicitDefs(MachineInstr *MI);
   };
 
@@ -84,24 +80,7 @@ LowerSubregsInstructionPass::TransferDeadFlag(MachineInstr *MI,
     if (MII->addRegisterDead(DstReg, TRI))
       break;
     assert(MII != MI->getParent()->begin() &&
-           "copyRegToReg output doesn't reference destination register!");
-  }
-}
-
-/// TransferKillFlag - MI is a pseudo-instruction with SrcReg killed,
-/// and the lowered replacement instructions immediately precede it.
-/// Mark the replacement instructions with the kill flag.
-void
-LowerSubregsInstructionPass::TransferKillFlag(MachineInstr *MI,
-                                              unsigned SrcReg,
-                                              const TargetRegisterInfo *TRI,
-                                              bool AddIfNotFound) {
-  for (MachineBasicBlock::iterator MII =
-        prior(MachineBasicBlock::iterator(MI)); ; --MII) {
-    if (MII->addRegisterKilled(SrcReg, TRI, AddIfNotFound))
-      break;
-    assert(MII != MI->getParent()->begin() &&
-           "copyRegToReg output doesn't reference source register!");
+           "copyPhysReg output doesn't reference destination register!");
   }
 }
 
@@ -121,63 +100,6 @@ LowerSubregsInstructionPass::TransferImplicitDefs(MachineInstr *MI) {
   }
 }
 
-bool LowerSubregsInstructionPass::LowerExtract(MachineInstr *MI) {
-  MachineBasicBlock *MBB = MI->getParent();
-
-  assert(MI->getOperand(0).isReg() && MI->getOperand(0).isDef() &&
-         MI->getOperand(1).isReg() && MI->getOperand(1).isUse() &&
-         MI->getOperand(2).isImm() && "Malformed extract_subreg");
-
-  unsigned DstReg   = MI->getOperand(0).getReg();
-  unsigned SuperReg = MI->getOperand(1).getReg();
-  unsigned SubIdx   = MI->getOperand(2).getImm();
-  unsigned SrcReg   = TRI->getSubReg(SuperReg, SubIdx);
-
-  assert(TargetRegisterInfo::isPhysicalRegister(SuperReg) &&
-         "Extract supperg source must be a physical register");
-  assert(TargetRegisterInfo::isPhysicalRegister(DstReg) &&
-         "Extract destination must be in a physical register");
-  assert(SrcReg && "invalid subregister index for register");
-
-  DEBUG(dbgs() << "subreg: CONVERTING: " << *MI);
-
-  if (SrcReg == DstReg) {
-    // No need to insert an identity copy instruction.
-    if (MI->getOperand(1).isKill()) {
-      // We must make sure the super-register gets killed. Replace the
-      // instruction with KILL.
-      MI->setDesc(TII->get(TargetOpcode::KILL));
-      MI->RemoveOperand(2);     // SubIdx
-      DEBUG(dbgs() << "subreg: replace by: " << *MI);
-      return true;
-    }
-
-    DEBUG(dbgs() << "subreg: eliminated!");
-  } else {
-    // Insert copy
-    const TargetRegisterClass *TRCS = TRI->getPhysicalRegisterRegClass(DstReg);
-    const TargetRegisterClass *TRCD = TRI->getPhysicalRegisterRegClass(SrcReg);
-    bool Emitted = TII->copyRegToReg(*MBB, MI, DstReg, SrcReg, TRCD, TRCS,
-                                     MI->getDebugLoc());
-    (void)Emitted;
-    assert(Emitted && "Subreg and Dst must be of compatible register class");
-    // Transfer the kill/dead flags, if needed.
-    if (MI->getOperand(0).isDead())
-      TransferDeadFlag(MI, DstReg, TRI);
-    if (MI->getOperand(1).isKill())
-      TransferKillFlag(MI, SuperReg, TRI, true);
-    TransferImplicitDefs(MI);
-    DEBUG({
-        MachineBasicBlock::iterator dMI = MI;
-        dbgs() << "subreg: " << *(--dMI);
-      });
-  }
-
-  DEBUG(dbgs() << '\n');
-  MBB->erase(MI);
-  return true;
-}
-
 bool LowerSubregsInstructionPass::LowerSubregToReg(MachineInstr *MI) {
   MachineBasicBlock *MBB = MI->getParent();
   assert((MI->getOperand(0).isReg() && MI->getOperand(0).isDef()) &&
@@ -214,18 +136,11 @@ bool LowerSubregsInstructionPass::LowerSubregToReg(MachineInstr *MI) {
     }
     DEBUG(dbgs() << "subreg: eliminated!");
   } else {
-    // Insert sub-register copy
-    const TargetRegisterClass *TRC0= TRI->getPhysicalRegisterRegClass(DstSubReg);
-    const TargetRegisterClass *TRC1= TRI->getPhysicalRegisterRegClass(InsReg);
-    bool Emitted = TII->copyRegToReg(*MBB, MI, DstSubReg, InsReg, TRC0, TRC1,
-                                     MI->getDebugLoc());
-    (void)Emitted;
-    assert(Emitted && "Subreg and Dst must be of compatible register class");
+    TII->copyPhysReg(*MBB, MI, MI->getDebugLoc(), DstSubReg, InsReg,
+                     MI->getOperand(2).isKill());
     // Transfer the kill/dead flags, if needed.
     if (MI->getOperand(0).isDead())
       TransferDeadFlag(MI, DstSubReg, TRI);
-    if (MI->getOperand(2).isKill())
-      TransferKillFlag(MI, InsReg, TRI);
     DEBUG({
         MachineBasicBlock::iterator dMI = MI;
         dbgs() << "subreg: " << *(--dMI);
@@ -258,21 +173,11 @@ bool LowerSubregsInstructionPass::LowerCopy(MachineInstr *MI) {
   }
 
   DEBUG(dbgs() << "real copy:   " << *MI);
-  // Ask target for a lowered copy instruction.
-  const TargetRegisterClass *DstRC =
-    TRI->getPhysicalRegisterRegClass(DstMO.getReg());
-  const TargetRegisterClass *SrcRC =
-    TRI->getPhysicalRegisterRegClass(SrcMO.getReg());
-  bool Emitted = TII->copyRegToReg(*MI->getParent(), MI,
-                                   DstMO.getReg(), SrcMO.getReg(),
-                                   DstRC, SrcRC, MI->getDebugLoc());
-  (void)Emitted;
-  assert(Emitted && "Cannot emit copy");
+  TII->copyPhysReg(*MI->getParent(), MI, MI->getDebugLoc(),
+                   DstMO.getReg(), SrcMO.getReg(), SrcMO.isKill());
 
   if (DstMO.isDead())
     TransferDeadFlag(MI, DstMO.getReg(), TRI);
-  if (SrcMO.isKill())
-    TransferKillFlag(MI, SrcMO.getReg(), TRI, true);
   if (MI->getNumOperands() > 2)
     TransferImplicitDefs(MI);
   DEBUG({
@@ -303,9 +208,9 @@ bool LowerSubregsInstructionPass::runOnMachineFunction(MachineFunction &MF) {
       MachineBasicBlock::iterator nmi = llvm::next(mi);
       MachineInstr *MI = mi;
       assert(!MI->isInsertSubreg() && "INSERT_SUBREG should no longer appear");
-      if (MI->isExtractSubreg()) {
-        MadeChange |= LowerExtract(MI);
-      } else if (MI->isSubregToReg()) {
+      assert(MI->getOpcode() != TargetOpcode::EXTRACT_SUBREG &&
+             "EXTRACT_SUBREG should no longer appear");
+      if (MI->isSubregToReg()) {
         MadeChange |= LowerSubregToReg(MI);
       } else if (MI->isCopy()) {
         MadeChange |= LowerCopy(MI);