Check that MnemonicAlias doesn't map back to the same string.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125792 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/utils/TableGen/AsmMatcherEmitter.cpp b/utils/TableGen/AsmMatcherEmitter.cpp
index 35f5f6facc49fa2dac7b9aaab614886d3cc326ca..e3def4185238f03903baea45c296caee0f4bec23 100644 (file)
--- a/utils/TableGen/AsmMatcherEmitter.cpp
+++ b/utils/TableGen/AsmMatcherEmitter.cpp
@@ -1881,6 +1881,8 @@ static bool EmitMnemonicAliases(raw_ostream &OS, const AsmMatcherInfo &Info) {
         AliasWithNoPredicate = i;
         continue;
       }
+      if (R->getValueAsString("ToMnemonic") == I->first)
+        throw TGError(R->getLoc(), "MnemonicAlias to the same string");
 
       if (!MatchCode.empty())
         MatchCode += "else ";