1 files changed, 7 insertions, 2 deletions
diff --git a/llvm/lib/CodeGen/PrologEpilogInserter.cpp b/llvm/lib/CodeGen/PrologEpilogInserter.cpp
index ddf48c7..c2b2399 100644
--- a/llvm/lib/CodeGen/PrologEpilogInserter.cpp
+++ b/llvm/lib/CodeGen/PrologEpilogInserter.cpp
@@ -1298,6 +1298,8 @@ void PEI::insertZeroCallUsedRegs(MachineFunction &MF) {
           continue;
 
         MCRegister Reg = MO.getReg();
+        if (!Reg)
+          continue;
 
         // This picks up sibling registers (e.q. %al -> %ah).
         for (MCRegUnit Unit : TRI.regunits(Reg))
@@ -1321,8 +1323,11 @@ void PEI::insertZeroCallUsedRegs(MachineFunction &MF) {
         if (!MO.isReg())
           continue;
 
-        for (const MCPhysReg &Reg :
-             TRI.sub_and_superregs_inclusive(MO.getReg()))
+        MCRegister Reg = MO.getReg();
+        if (!Reg)
+          continue;
+
+        for (const MCPhysReg Reg : TRI.sub_and_superregs_inclusive(Reg))
           RegsToZero.reset(Reg);
       }
     }