[mir] Print/Parse both MOLoad and MOStore when they occur together.

Summary:
They're not always mutually exclusive. read-modify-write atomics are both
at the same time. One example of this is the SWP instructions on AArch64.
Another example is GlobalISel's G_ATOMICRMW_* generic instructions which
will be added in a later patch.

Reviewers: arphaman, aemerson

Reviewed By: aemerson

Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D40157

llvm-svn: 319202

1 files changed, 11 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/MIRParser/MIParser.cpp b/llvm/lib/CodeGen/MIRParser/MIParser.cpp
index 10dbaf7045e..9b5539a7ca7 100644
--- a/llvm/lib/CodeGen/MIRParser/MIParser.cpp
+++ b/llvm/lib/CodeGen/MIRParser/MIParser.cpp
@@ -2280,6 +2280,12 @@ bool MIParser::parseMachineMemoryOperand(MachineMemOperand *&Dest) {
     Flags |= MachineMemOperand::MOStore;
   lex();
 
+  // Optional 'store' for operands that both load and store.
+  if (Token.is(MIToken::Identifier) && Token.stringValue() == "store") {
+    Flags |= MachineMemOperand::MOStore;
+    lex();
+  }
+
   // Optional synchronization scope.
   SyncScope::ID SSID;
   if (parseOptionalScope(MF.getFunction()->getContext(), SSID))
@@ -2302,7 +2308,11 @@ bool MIParser::parseMachineMemoryOperand(MachineMemOperand *&Dest) {
 
   MachinePointerInfo Ptr = MachinePointerInfo();
   if (Token.is(MIToken::Identifier)) {
-    const char *Word = Flags & MachineMemOperand::MOLoad ? "from" : "into";
+    const char *Word =
+        ((Flags & MachineMemOperand::MOLoad) &&
+         (Flags & MachineMemOperand::MOStore))
+            ? "on"
+            : Flags & MachineMemOperand::MOLoad ? "from" : "into";
     if (Token.stringValue() != Word)
       return error(Twine("expected '") + Word + "'");
     lex();