diff options
| -rw-r--r-- | include/llvm/CodeGen/MachineRegisterInfo.h | 4 | ||||
| -rw-r--r-- | lib/CodeGen/MachineFunction.cpp | 10 | ||||
| -rw-r--r-- | lib/CodeGen/MachineRegisterInfo.cpp | 9 |
3 files changed, 21 insertions, 2 deletions
diff --git a/include/llvm/CodeGen/MachineRegisterInfo.h b/include/llvm/CodeGen/MachineRegisterInfo.h index dede05f85c..fa14fdc3f1 100644 --- a/include/llvm/CodeGen/MachineRegisterInfo.h +++ b/include/llvm/CodeGen/MachineRegisterInfo.h @@ -293,6 +293,10 @@ public: /// 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, diff --git a/lib/CodeGen/MachineFunction.cpp b/lib/CodeGen/MachineFunction.cpp index 3cf10b3ac6..a38c881982 100644 --- a/lib/CodeGen/MachineFunction.cpp +++ b/lib/CodeGen/MachineFunction.cpp @@ -398,8 +398,14 @@ void MachineFunction::viewCFGOnly() const 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; } diff --git a/lib/CodeGen/MachineRegisterInfo.cpp b/lib/CodeGen/MachineRegisterInfo.cpp index 402be479ea..70bf7e5da5 100644 --- a/lib/CodeGen/MachineRegisterInfo.cpp +++ b/lib/CodeGen/MachineRegisterInfo.cpp @@ -165,6 +165,15 @@ unsigned MachineRegisterInfo::getLiveInPhysReg(unsigned VReg) const { 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"), |