4 files changed, 38 insertions, 5 deletions
diff --git a/llvm/docs/MIRLangRef.rst b/llvm/docs/MIRLangRef.rst
index 14ac63bbd9d..f170c721087 100644
--- a/llvm/docs/MIRLangRef.rst
+++ b/llvm/docs/MIRLangRef.rst
@@ -121,6 +121,8 @@ Tests are more accessible and future proof when simplified:
   contains dummy functions (see above). The .mir loader will create the
   IR functions automatically in this case.
 
+.. _limitations:
+
 Limitations
 -----------
 
@@ -678,6 +680,17 @@ Example:
 
     CALL64pcrel32 $__stack_chk_fail, csr_64, implicit %rsp, implicit-def %rsp
 
+MCSymbol Operands
+^^^^^^^^^^^^^^^^^
+
+A MCSymbol operand is holding a pointer to a ``MCSymbol``. For the limitations
+of this operand in MIR, see :ref:`limitations <limitations>`.
+
+The syntax is:
+
+.. code-block:: text
+
+    EH_LABEL <mcsymbol Ltmp1>
 
 .. TODO: Describe the parsers default behaviour when optional YAML attributes
    are missing.
diff --git a/llvm/lib/CodeGen/MIRPrinter.cpp b/llvm/lib/CodeGen/MIRPrinter.cpp
index 723e57b4444..ac94e96bea8 100644
--- a/llvm/lib/CodeGen/MIRPrinter.cpp
+++ b/llvm/lib/CodeGen/MIRPrinter.cpp
@@ -799,7 +799,8 @@ void MIPrinter::print(const MachineInstr &MI, unsigned OpIdx,
   case MachineOperand::MO_ExternalSymbol:
   case MachineOperand::MO_GlobalAddress:
   case MachineOperand::MO_RegisterLiveOut:
-  case MachineOperand::MO_Metadata: {
+  case MachineOperand::MO_Metadata:
+  case MachineOperand::MO_MCSymbol: {
     unsigned TiedOperandIdx = 0;
     if (ShouldPrintRegisterTies && Op.isReg() && Op.isTied() && !Op.isDef())
       TiedOperandIdx = Op.getParent()->findTiedOperandIdx(OpIdx);
@@ -831,9 +832,6 @@ void MIPrinter::print(const MachineInstr &MI, unsigned OpIdx,
       printCustomRegMask(Op.getRegMask(), OS, TRI);
     break;
   }
-  case MachineOperand::MO_MCSymbol:
-    OS << "<mcsymbol " << *Op.getMCSymbol() << ">";
-    break;
   case MachineOperand::MO_CFIIndex: {
     const MachineFunction &MF = *Op.getParent()->getMF();
     print(MF.getFrameInstructions()[Op.getCFIIndex()], TRI);
diff --git a/llvm/lib/CodeGen/MachineOperand.cpp b/llvm/lib/CodeGen/MachineOperand.cpp
index a1ae5d396c2..1640d57eb48 100644
--- a/llvm/lib/CodeGen/MachineOperand.cpp
+++ b/llvm/lib/CodeGen/MachineOperand.cpp
@@ -660,7 +660,7 @@ void MachineOperand::print(raw_ostream &OS, ModuleSlotTracker &MST,
     getMetadata()->printAsOperand(OS, MST);
     break;
   case MachineOperand::MO_MCSymbol:
-    OS << "<MCSym=" << *getMCSymbol() << '>';
+    OS << "<mcsymbol " << *getMCSymbol() << ">";
     break;
   case MachineOperand::MO_CFIIndex:
     OS << "<call frame instruction>";
diff --git a/llvm/unittests/CodeGen/MachineOperandTest.cpp b/llvm/unittests/CodeGen/MachineOperandTest.cpp
index 192229be065..e51207b9571 100644
--- a/llvm/unittests/CodeGen/MachineOperandTest.cpp
+++ b/llvm/unittests/CodeGen/MachineOperandTest.cpp
@@ -13,6 +13,8 @@
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/ModuleSlotTracker.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCAsmInfo.h"
 #include "llvm/Support/raw_ostream.h"
 #include "gtest/gtest.h"
 
@@ -314,4 +316,24 @@ TEST(MachineOperandTest, PrintMetadata) {
   ASSERT_TRUE(OS.str() == "!0");
 }
 
+TEST(MachineOperandTest, PrintMCSymbol) {
+  MCAsmInfo MAI;
+  MCContext Ctx(&MAI, /*MRI=*/nullptr, /*MOFI=*/nullptr);
+  MCSymbol *Sym = Ctx.getOrCreateSymbol("foo");
+
+  // Create a MachineOperand with a metadata and print it.
+  MachineOperand MO = MachineOperand::CreateMCSymbol(Sym);
+
+  // Checking some preconditions on the newly created
+  // MachineOperand.
+  ASSERT_TRUE(MO.isMCSymbol());
+  ASSERT_TRUE(MO.getMCSymbol() == Sym);
+
+  std::string str;
+  // Print a MachineOperand containing a metadata node.
+  raw_string_ostream OS(str);
+  MO.print(OS, /*TRI=*/nullptr, /*IntrinsicInfo=*/nullptr);
+  ASSERT_TRUE(OS.str() == "<mcsymbol foo>");
+}
+
 } // end namespace