diff options
| -rw-r--r-- | include/llvm/CodeGen/MachineRegisterInfo.h | 5 | ||||
| -rw-r--r-- | lib/CodeGen/MachineRegisterInfo.cpp | 11 |
2 files changed, 16 insertions, 0 deletions
diff --git a/include/llvm/CodeGen/MachineRegisterInfo.h b/include/llvm/CodeGen/MachineRegisterInfo.h index 5a82caa9ac..2bcd1c72ce 100644 --- a/include/llvm/CodeGen/MachineRegisterInfo.h +++ b/include/llvm/CodeGen/MachineRegisterInfo.h @@ -237,6 +237,11 @@ public: /// form, so there should only be one definition. MachineInstr *getVRegDef(unsigned Reg) const; + /// getUniqueVRegDef - Return the unique machine instr that defines the + /// specified virtual register or null if none is found. If there are + /// multiple definitions or no definition, return null. + MachineInstr *getUniqueVRegDef(unsigned Reg) const; + /// clearKillFlags - Iterate over all the uses of the given register and /// clear the kill flag from the MachineOperand. This function is used by /// optimization passes which extend register lifetimes and need only diff --git a/lib/CodeGen/MachineRegisterInfo.cpp b/lib/CodeGen/MachineRegisterInfo.cpp index 9c0d749a26..863da72774 100644 --- a/lib/CodeGen/MachineRegisterInfo.cpp +++ b/lib/CodeGen/MachineRegisterInfo.cpp @@ -165,6 +165,17 @@ MachineInstr *MachineRegisterInfo::getVRegDef(unsigned Reg) const { return !I.atEnd() ? &*I : 0; } +/// getUniqueVRegDef - Return the unique machine instr that defines the +/// specified virtual register or null if none is found. If there are +/// multiple definitions or no definition, return null. +MachineInstr *MachineRegisterInfo::getUniqueVRegDef(unsigned Reg) const { + if (def_empty(Reg)) return 0; + def_iterator I = def_begin(Reg); + if (llvm::next(I) != def_end()) + return 0; + return &*I; +} + bool MachineRegisterInfo::hasOneUse(unsigned RegNo) const { use_iterator UI = use_begin(RegNo); if (UI == use_end()) |