[llvm-commits] [llvm] r105100 - /llvm/trunk/lib/CodeGen/MachineRegisterInfo.cpp

Benjamin Kramer benny.kra at googlemail.com
Sat May 29 07:03:51 PDT 2010


Author: d0k
Date: Sat May 29 09:03:51 2010
New Revision: 105100

URL: http://llvm.org/viewvc/llvm-project?rev=105100&view=rev
Log:
Remove unused function.

Modified:
    llvm/trunk/lib/CodeGen/MachineRegisterInfo.cpp

Modified: llvm/trunk/lib/CodeGen/MachineRegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/MachineRegisterInfo.cpp?rev=105100&r1=105099&r2=105100&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/MachineRegisterInfo.cpp (original)
+++ llvm/trunk/lib/CodeGen/MachineRegisterInfo.cpp Sat May 29 09:03:51 2010
@@ -174,75 +174,6 @@
   return 0;
 }
 
-/// EmitLiveInCopy - Emit a copy for a live in physical register. If the
-/// physical register has only a single copy use, then coalesced the copy
-/// if possible.
-static void EmitLiveInCopy(MachineBasicBlock *MBB,
-                           MachineBasicBlock::iterator &InsertPos,
-                           unsigned VirtReg, unsigned PhysReg,
-                           const TargetRegisterClass *RC,
-                           DenseMap<MachineInstr*, unsigned> &CopyRegMap,
-                           const MachineRegisterInfo &MRI,
-                           const TargetRegisterInfo &TRI,
-                           const TargetInstrInfo &TII) {
-  unsigned NumUses = 0;
-  MachineInstr *UseMI = NULL;
-  for (MachineRegisterInfo::use_iterator UI = MRI.use_begin(VirtReg),
-         UE = MRI.use_end(); UI != UE; ++UI) {
-    UseMI = &*UI;
-    if (++NumUses > 1)
-      break;
-  }
-
-  // If the number of uses is not one, or the use is not a move instruction,
-  // don't coalesce. Also, only coalesce away a virtual register to virtual
-  // register copy.
-  bool Coalesced = false;
-  unsigned SrcReg, DstReg, SrcSubReg, DstSubReg;
-  if (NumUses == 1 &&
-      TII.isMoveInstr(*UseMI, SrcReg, DstReg, SrcSubReg, DstSubReg) &&
-      TargetRegisterInfo::isVirtualRegister(DstReg)) {
-    VirtReg = DstReg;
-    Coalesced = true;
-  }
-
-  // Now find an ideal location to insert the copy.
-  MachineBasicBlock::iterator Pos = InsertPos;
-  while (Pos != MBB->begin()) {
-    MachineInstr *PrevMI = prior(Pos);
-    DenseMap<MachineInstr*, unsigned>::iterator RI = CopyRegMap.find(PrevMI);
-    // copyRegToReg might emit multiple instructions to do a copy.
-    unsigned CopyDstReg = (RI == CopyRegMap.end()) ? 0 : RI->second;
-    if (CopyDstReg && !TRI.regsOverlap(CopyDstReg, PhysReg))
-      // This is what the BB looks like right now:
-      // r1024 = mov r0
-      // ...
-      // r1    = mov r1024
-      //
-      // We want to insert "r1025 = mov r1". Inserting this copy below the
-      // move to r1024 makes it impossible for that move to be coalesced.
-      //
-      // r1025 = mov r1
-      // r1024 = mov r0
-      // ...
-      // r1    = mov 1024
-      // r2    = mov 1025
-      break; // Woot! Found a good location.
-    --Pos;
-  }
-
-  bool Emitted = TII.copyRegToReg(*MBB, Pos, VirtReg, PhysReg, RC, RC,
-                                  DebugLoc());
-  assert(Emitted && "Unable to issue a live-in copy instruction!\n");
-  (void) Emitted;
-
-  CopyRegMap.insert(std::make_pair(prior(Pos), VirtReg));
-  if (Coalesced) {
-    if (&*InsertPos == UseMI) ++InsertPos;
-    MBB->erase(UseMI);
-  }
-}
-
 /// EmitLiveInCopies - Emit copies to initialize livein virtual registers
 /// into the given entry block.
 void





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