Remove cache for macro arg stringization

Summary:
The cache recorded the wrong expansion location for all but the first
stringization. It seems uncommon to stringize the same macro argument
multiple times, so this cache doesn't seem that important.

Fixes PR39942

Reviewers: vsk, rsmith

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D65428

llvm-svn: 367337

2 files changed, 4 insertions, 32 deletions

diff --git a/clang/lib/Lex/MacroArgs.cpp b/clang/lib/Lex/MacroArgs.cpp
index 5aa4679fad4..7ede00b4aa6 100644
--- a/clang/lib/Lex/MacroArgs.cpp
+++ b/clang/lib/Lex/MacroArgs.cpp
@@ -76,8 +76,6 @@ MacroArgs *MacroArgs::create(const MacroInfo *MI,
 /// destroy - Destroy and deallocate the memory for this object.
 ///
 void MacroArgs::destroy(Preprocessor &PP) {
-  StringifiedArgs.clear();
-
   // Don't clear PreExpArgTokens, just clear the entries.  Clearing the entries
   // would deallocate the element vectors.
   for (unsigned i = 0, e = PreExpArgTokens.size(); i != e; ++i)
@@ -307,21 +305,3 @@ Token MacroArgs::StringifyArgument(const Token *ArgToks,
                   ExpansionLocStart, ExpansionLocEnd);
   return Tok;
 }
-
-/// getStringifiedArgument - Compute, cache, and return the specified argument
-/// that has been 'stringified' as required by the # operator.
-const Token &MacroArgs::getStringifiedArgument(unsigned ArgNo,
-                                               Preprocessor &PP,
-                                               SourceLocation ExpansionLocStart,
-                                               SourceLocation ExpansionLocEnd) {
-  assert(ArgNo < getNumMacroArguments() && "Invalid argument number!");
-  if (StringifiedArgs.empty())
-    StringifiedArgs.resize(getNumMacroArguments(), {});
-
-  if (StringifiedArgs[ArgNo].isNot(tok::string_literal))
-    StringifiedArgs[ArgNo] = StringifyArgument(getUnexpArgument(ArgNo), PP,
-                                               /*Charify=*/false,
-                                               ExpansionLocStart,
-                                               ExpansionLocEnd);
-  return StringifiedArgs[ArgNo];
-}
diff --git a/clang/lib/Lex/TokenLexer.cpp b/clang/lib/Lex/TokenLexer.cpp
index a7957e82e49..da5681aaf47 100644
--- a/clang/lib/Lex/TokenLexer.cpp
+++ b/clang/lib/Lex/TokenLexer.cpp
@@ -383,18 +383,10 @@ void TokenLexer::ExpandFunctionArguments() {
       SourceLocation ExpansionLocEnd =
           getExpansionLocForMacroDefLoc(Tokens[I+1].getLocation());
 
-      Token Res;
-      if (CurTok.is(tok::hash))  // Stringify
-        Res = ActualArgs->getStringifiedArgument(ArgNo, PP,
-                                                 ExpansionLocStart,
-                                                 ExpansionLocEnd);
-      else {
-        // 'charify': don't bother caching these.
-        Res = MacroArgs::StringifyArgument(ActualArgs->getUnexpArgument(ArgNo),
-                                           PP, true,
-                                           ExpansionLocStart,
-                                           ExpansionLocEnd);
-      }
+      bool Charify = CurTok.is(tok::hashat);
+      const Token *UnexpArg = ActualArgs->getUnexpArgument(ArgNo);
+      Token Res = MacroArgs::StringifyArgument(
+          UnexpArg, PP, Charify, ExpansionLocStart, ExpansionLocEnd);
       Res.setFlag(Token::StringifiedInMacro);
 
       // The stringified/charified string leading space flag gets set to match