Add TargetInstrInfo::copyPhysReg hook and use it from LowerSubregs.

This target hook is intended to replace copyRegToReg entirely, but for now it
calls copyRegToReg.

Any remaining calls to copyRegToReg wil be replaced by COPY instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107854 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 8 insertions, 36 deletions

diff --git a/lib/CodeGen/LowerSubregs.cpp b/lib/CodeGen/LowerSubregs.cpp
index 172e4b5795..4ba8adab12 100644
--- a/lib/CodeGen/LowerSubregs.cpp
+++ b/lib/CodeGen/LowerSubregs.cpp
@@ -85,7 +85,7 @@ LowerSubregsInstructionPass::TransferDeadFlag(MachineInstr *MI,
     if (MII->addRegisterDead(DstReg, TRI))
       break;
     assert(MII != MI->getParent()->begin() &&
-           "copyRegToReg output doesn't reference destination register!");
+           "copyPhysReg output doesn't reference destination register!");
   }
 }
 
@@ -102,7 +102,7 @@ LowerSubregsInstructionPass::TransferKillFlag(MachineInstr *MI,
     if (MII->addRegisterKilled(SrcReg, TRI, AddIfNotFound))
       break;
     assert(MII != MI->getParent()->begin() &&
-           "copyRegToReg output doesn't reference source register!");
+           "copyPhysReg output doesn't reference source register!");
   }
 }
 
@@ -155,13 +155,7 @@ bool LowerSubregsInstructionPass::LowerExtract(MachineInstr *MI) {
 
     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");
+    TII->copyPhysReg(*MBB, MI, MI->getDebugLoc(), DstReg, SrcReg, false);
     // Transfer the kill/dead flags, if needed.
     if (MI->getOperand(0).isDead())
       TransferDeadFlag(MI, DstReg, TRI);
@@ -215,18 +209,11 @@ 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);
@@ -280,18 +267,13 @@ bool LowerSubregsInstructionPass::LowerInsert(MachineInstr *MI) {
     }
   } else {
     // Insert sub-register copy
-    const TargetRegisterClass *TRC0= TRI->getPhysicalRegisterRegClass(DstSubReg);
-    const TargetRegisterClass *TRC1= TRI->getPhysicalRegisterRegClass(InsReg);
     if (MI->getOperand(2).isUndef())
       // If the source register being inserted is undef, then this becomes a
       // KILL.
       BuildMI(*MBB, MI, MI->getDebugLoc(),
               TII->get(TargetOpcode::KILL), DstSubReg);
     else {
-      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, false);
     }
     MachineBasicBlock::iterator CopyMI = MI;
     --CopyMI;
@@ -343,21 +325,11 @@ 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({