Add MachineRegisterInfo::hasOneUse and hasOneNonDBGUse.

llvm-svn: 97663

2 files changed, 16 insertions, 6 deletions

diff --git a/llvm/lib/CodeGen/MachineRegisterInfo.cpp b/llvm/lib/CodeGen/MachineRegisterInfo.cpp
index b31973e04fd..d9ab6773a53 100644
--- a/llvm/lib/CodeGen/MachineRegisterInfo.cpp
+++ b/llvm/lib/CodeGen/MachineRegisterInfo.cpp
@@ -116,6 +116,19 @@ MachineInstr *MachineRegisterInfo::getVRegDef(unsigned Reg) const {
   return 0;
 }
 
+bool MachineRegisterInfo::hasOneUse(unsigned RegNo) const {
+  use_iterator UI = use_begin(RegNo);
+  if (UI == use_end())
+    return false;
+  return ++UI == use_end();
+}
+
+bool MachineRegisterInfo::hasOneNonDBGUse(unsigned RegNo) const {
+  use_nodbg_iterator UI = use_nodbg_begin(RegNo);
+  if (UI == use_nodbg_end())
+    return false;
+  return ++UI == use_nodbg_end();
+}
 
 #ifndef NDEBUG
 void MachineRegisterInfo::dumpUses(unsigned Reg) const {
diff --git a/llvm/lib/CodeGen/TwoAddressInstructionPass.cpp b/llvm/lib/CodeGen/TwoAddressInstructionPass.cpp
index 0ba38433c22..c840b3968cd 100644
--- a/llvm/lib/CodeGen/TwoAddressInstructionPass.cpp
+++ b/llvm/lib/CodeGen/TwoAddressInstructionPass.cpp
@@ -454,13 +454,10 @@ MachineInstr *findOnlyInterestingUse(unsigned Reg, MachineBasicBlock *MBB,
                                      const TargetInstrInfo *TII,
                                      bool &IsCopy,
                                      unsigned &DstReg, bool &IsDstPhys) {
-  MachineRegisterInfo::use_nodbg_iterator UI = MRI->use_nodbg_begin(Reg);
-  if (UI == MRI->use_nodbg_end())
-    return 0;
-  MachineInstr &UseMI = *UI;
-  if (++UI != MRI->use_nodbg_end())
-    // More than one use.
+  if (!MRI->hasOneNonDBGUse(Reg))
+    // None or more than one use.
     return 0;
+  MachineInstr &UseMI = *MRI->use_nodbg_begin(Reg);
   if (UseMI.getParent() != MBB)
     return 0;
   unsigned SrcReg;