4 files changed, 10 insertions, 2 deletions
diff --git a/llvm/lib/CodeGen/MIRParser/MILexer.cpp b/llvm/lib/CodeGen/MIRParser/MILexer.cpp
index 37e71edea4e..4baa3859461 100644
--- a/llvm/lib/CodeGen/MIRParser/MILexer.cpp
+++ b/llvm/lib/CodeGen/MIRParser/MILexer.cpp
@@ -72,6 +72,7 @@ static MIToken::TokenKind getIdentifierKind(StringRef Identifier) {
       .Case("implicit-def", MIToken::kw_implicit_define)
       .Case("dead", MIToken::kw_dead)
       .Case("killed", MIToken::kw_killed)
+      .Case("undef", MIToken::kw_undef)
       .Default(MIToken::Identifier);
 }
 
diff --git a/llvm/lib/CodeGen/MIRParser/MILexer.h b/llvm/lib/CodeGen/MIRParser/MILexer.h
index 610a7b95b40..ef471d250c2 100644
--- a/llvm/lib/CodeGen/MIRParser/MILexer.h
+++ b/llvm/lib/CodeGen/MIRParser/MILexer.h
@@ -41,6 +41,7 @@ struct MIToken {
     kw_implicit_define,
     kw_dead,
     kw_killed,
+    kw_undef,
 
     // Identifier tokens
     Identifier,
@@ -77,7 +78,7 @@ public:
 
   bool isRegisterFlag() const {
     return Kind == kw_implicit || Kind == kw_implicit_define ||
-           Kind == kw_dead || Kind == kw_killed;
+           Kind == kw_dead || Kind == kw_killed || Kind == kw_undef;
   }
 
   bool is(TokenKind K) const { return Kind == K; }
diff --git a/llvm/lib/CodeGen/MIRParser/MIParser.cpp b/llvm/lib/CodeGen/MIRParser/MIParser.cpp
index 0664c5170af..7fd794bd211 100644
--- a/llvm/lib/CodeGen/MIRParser/MIParser.cpp
+++ b/llvm/lib/CodeGen/MIRParser/MIParser.cpp
@@ -309,6 +309,9 @@ bool MIParser::parseRegisterFlag(unsigned &Flags) {
   case MIToken::kw_killed:
     Flags |= RegState::Kill;
     break;
+  case MIToken::kw_undef:
+    Flags |= RegState::Undef;
+    break;
   // TODO: report an error when we specify the same flag more than once.
   // TODO: parse the other register flags.
   default:
@@ -333,7 +336,7 @@ bool MIParser::parseRegisterOperand(MachineOperand &Dest, bool IsDef) {
   // TODO: Parse subregister.
   Dest = MachineOperand::CreateReg(
       Reg, Flags & RegState::Define, Flags & RegState::Implicit,
-      Flags & RegState::Kill, Flags & RegState::Dead);
+      Flags & RegState::Kill, Flags & RegState::Dead, Flags & RegState::Undef);
   return false;
 }
 
@@ -419,6 +422,7 @@ bool MIParser::parseMachineOperand(MachineOperand &Dest) {
   case MIToken::kw_implicit_define:
   case MIToken::kw_dead:
   case MIToken::kw_killed:
+  case MIToken::kw_undef:
   case MIToken::underscore:
   case MIToken::NamedRegister:
     return parseRegisterOperand(Dest);
diff --git a/llvm/lib/CodeGen/MIRPrinter.cpp b/llvm/lib/CodeGen/MIRPrinter.cpp
index e3b515b54cc..d2e32ecd23f 100644
--- a/llvm/lib/CodeGen/MIRPrinter.cpp
+++ b/llvm/lib/CodeGen/MIRPrinter.cpp
@@ -220,6 +220,8 @@ void MIPrinter::print(const MachineOperand &Op, const TargetRegisterInfo *TRI) {
       OS << "dead ";
     if (Op.isKill())
       OS << "killed ";
+    if (Op.isUndef())
+      OS << "undef ";
     printReg(Op.getReg(), OS, TRI);
     // TODO: Print sub register.
     break;