[AsmParser]Emit an error if a macro has two (or more) parameters sharing the same name

Introducing a new error to macro parameters' parsing:
currently, llvm-mc won't complain if a macro have two (or more) named params with the same name.
this behavior is false, as there's no merit in having some params sharing a name.
now, instead of tolerate such a phenomena - emit an appropriate error.

Differential Revision: https://reviews.llvm.org/D31674

llvm-svn: 299815

1 files changed, 6 insertions, 0 deletions

diff --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp
index 9d5eaf31408..e65ce9f0b93 100644
--- a/llvm/lib/MC/MCParser/AsmParser.cpp
+++ b/llvm/lib/MC/MCParser/AsmParser.cpp
@@ -3874,6 +3874,12 @@ bool AsmParser::parseDirectiveMacro(SMLoc DirectiveLoc) {
     if (parseIdentifier(Parameter.Name))
       return TokError("expected identifier in '.macro' directive");
 
+    // Emit an error if two (or more) named parameters share the same name
+    for (const MCAsmMacroParameter& CurrParam : Parameters)
+      if (CurrParam.Name.equals(Parameter.Name))
+        return TokError("macro '" + Name + "' has multiple parameters"
+                        " named '" + Parameter.Name + "'");
+
     if (Lexer.is(AsmToken::Colon)) {
       Lex();  // consume ':'