Allow the commuted form of tied-operand constraints in tablegen ("$dst = $src",
rather than "$src = $dst").
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166382 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/CodeGenInstruction.cpp b/utils/TableGen/CodeGenInstruction.cpp
index 99d2f17..fd38672 100644
--- a/utils/TableGen/CodeGenInstruction.cpp
+++ b/utils/TableGen/CodeGenInstruction.cpp
@@ -233,11 +233,12 @@
if (wpos == std::string::npos)
throw "Illegal format for tied-to constraint: '" + CStr + "'";
- std::pair<unsigned,unsigned> SrcOp =
- Ops.ParseOperandName(Name.substr(wpos), false);
- if (SrcOp > DestOp)
- throw "Illegal tied-to operand constraint '" + CStr + "'";
-
+ std::string SrcOpName = Name.substr(wpos);
+ std::pair<unsigned,unsigned> SrcOp = Ops.ParseOperandName(SrcOpName, false);
+ if (SrcOp > DestOp) {
+ std::swap(SrcOp, DestOp);
+ std::swap(SrcOpName, DestOpName);
+ }
unsigned FlatOpNo = Ops.getFlattenedOperandNumber(SrcOp);