Added assertion in getVRegDef of MachineRegisterInfo to make sure the virtual

[oota-llvm.git] / lib / CodeGen / MachineRegisterInfo.cpp

diff --git a/lib/CodeGen/MachineRegisterInfo.cpp b/lib/CodeGen/MachineRegisterInfo.cpp
index 863da72774e2d3a4de7b3dd30debf62f5d98ac95..82e123528acc84a2d6060bfd765de7427cc45dd2 100644 (file)
--- a/lib/CodeGen/MachineRegisterInfo.cpp
+++ b/lib/CodeGen/MachineRegisterInfo.cpp
@@ -162,6 +162,8 @@ void MachineRegisterInfo::replaceRegWith(unsigned FromReg, unsigned ToReg) {
 MachineInstr *MachineRegisterInfo::getVRegDef(unsigned Reg) const {
   // Since we are in SSA form, we can use the first definition.
   def_iterator I = def_begin(Reg);
+  assert((I.atEnd() || llvm::next(I) == def_end()) &&
+         "getVRegDef assumes a single definition or no definition");
   return !I.atEnd() ? &*I : 0;
 }