[llvm-commits] [llvm] r104560 - in /llvm/trunk: include/llvm/CodeGen/MachineRegisterInfo.h lib/CodeGen/MachineFunction.cpp lib/CodeGen/MachineRegisterInfo.cpp

[Evan Cheng]

Author: evancheng
Date: Mon May 24 16:33:37 2010
New Revision: 104560

URL: http://llvm.org/viewvc/llvm-project?rev=104560&view=rev
Log:
Avoid adding duplicate function live-in's.

Modified:
    llvm/trunk/include/llvm/CodeGen/MachineRegisterInfo.h
    llvm/trunk/lib/CodeGen/MachineFunction.cpp
    llvm/trunk/lib/CodeGen/MachineRegisterInfo.cpp

Modified: llvm/trunk/include/llvm/CodeGen/MachineRegisterInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/MachineRegisterInfo.h?rev=104560&r1=104559&r2=104560&view=diff
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/MachineRegisterInfo.h (original)
+++ llvm/trunk/include/llvm/CodeGen/MachineRegisterInfo.h Mon May 24 16:33:37 2010
@@ -293,6 +293,10 @@
   /// corresponding live-in physical register.
   unsigned getLiveInPhysReg(unsigned VReg) const;
 
+  /// getLiveInVirtReg - If PReg is a live-in physical register, return the
+  /// corresponding live-in physical register.
+  unsigned getLiveInVirtReg(unsigned PReg) const;
+
   /// EmitLiveInCopies - Emit copies to initialize livein virtual registers
   /// into the given entry block.
   void EmitLiveInCopies(MachineBasicBlock *EntryMBB,

Modified: llvm/trunk/lib/CodeGen/MachineFunction.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/MachineFunction.cpp?rev=104560&r1=104559&r2=104560&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/MachineFunction.cpp (original)
+++ llvm/trunk/lib/CodeGen/MachineFunction.cpp Mon May 24 16:33:37 2010
@@ -398,8 +398,14 @@
 unsigned MachineFunction::addLiveIn(unsigned PReg,
                                     const TargetRegisterClass *RC) {
   assert(RC->contains(PReg) && "Not the correct regclass!");
-  unsigned VReg = getRegInfo().createVirtualRegister(RC);
-  getRegInfo().addLiveIn(PReg, VReg);
+  MachineRegisterInfo &MRI = getRegInfo();
+  unsigned VReg = MRI.getLiveInVirtReg(PReg);
+  if (VReg) {
+    assert(MRI.getRegClass(VReg) == RC && "Register class mismatch!");
+    return VReg;
+  }
+  VReg = MRI.createVirtualRegister(RC);
+  MRI.addLiveIn(PReg, VReg);
   return VReg;
 }
 

Modified: llvm/trunk/lib/CodeGen/MachineRegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/MachineRegisterInfo.cpp?rev=104560&r1=104559&r2=104560&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/MachineRegisterInfo.cpp (original)
+++ llvm/trunk/lib/CodeGen/MachineRegisterInfo.cpp Mon May 24 16:33:37 2010
@@ -165,6 +165,15 @@
   return 0;
 }
 
+/// getLiveInVirtReg - If PReg is a live-in physical register, return the
+/// corresponding live-in physical register.
+unsigned MachineRegisterInfo::getLiveInVirtReg(unsigned PReg) const {
+  for (livein_iterator I = livein_begin(), E = livein_end(); I != E; ++I)
+    if (I->first == PReg)
+      return I->second;
+  return 0;
+}
+
 static cl::opt<bool>
 SchedLiveInCopies("schedule-livein-copies", cl::Hidden,
                   cl::desc("Schedule copies of livein registers"),