Keep the IdentifierInfo in the Token for alternative operator keyword

The goal of this commit is to fix clang-format so it does not merge tokens when
using the alternative spelling keywords. (eg: "not foo" should not become "notfoo")

The problem is that Preprocessor::HandleIdentifier used to drop the identifier info
from the token for these keyword. This means the first condition of
TokenAnnotator::spaceRequiredBefore is not met. We could add explicit check for
the spelling in that condition, but I think it is better to keep the IdentifierInfo
and handle the operator keyword explicitly when needed. That actually leads to simpler
code, and probably slightly more efficient as well.

Another side effect of this change is that __identifier(and) will now work as
one would expect, removing a FIXME from the MicrosoftExtensions.cpp test

Differential Revision: https://reviews.llvm.org/D35172

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@308008 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 35 insertions, 46 deletions

diff --git a/lib/Lex/PPDirectives.cpp b/lib/Lex/PPDirectives.cpp
index 8c79e50176..4440cf2094 100644
--- a/lib/Lex/PPDirectives.cpp
+++ b/lib/Lex/PPDirectives.cpp
@@ -220,26 +220,18 @@ bool Preprocessor::CheckMacroName(Token &MacroNameTok, MacroUse isDefineUndef,
     return Diag(MacroNameTok, diag::err_pp_missing_macro_name);
 
   IdentifierInfo *II = MacroNameTok.getIdentifierInfo();
-  if (!II) {
-    bool Invalid = false;
-    std::string Spelling = getSpelling(MacroNameTok, &Invalid);
-    if (Invalid)
-      return Diag(MacroNameTok, diag::err_pp_macro_not_identifier);
-    II = getIdentifierInfo(Spelling);
-
-    if (!II->isCPlusPlusOperatorKeyword())
-      return Diag(MacroNameTok, diag::err_pp_macro_not_identifier);
+  if (!II)
+    return Diag(MacroNameTok, diag::err_pp_macro_not_identifier);
 
+  if (II->isCPlusPlusOperatorKeyword()) {
     // C++ 2.5p2: Alternative tokens behave the same as its primary token
     // except for their spellings.
     Diag(MacroNameTok, getLangOpts().MicrosoftExt
                            ? diag::ext_pp_operator_used_as_macro_name
                            : diag::err_pp_operator_used_as_macro_name)
         << II << MacroNameTok.getKind();
-
     // Allow #defining |and| and friends for Microsoft compatibility or
     // recovery when legacy C headers are included in C++.
-    MacroNameTok.setIdentifierInfo(II);
   }
 
   if ((isDefineUndef != MU_Other) && II->getPPKeywordID() == tok::pp_defined) {
diff --git a/lib/Lex/PPExpressions.cpp b/lib/Lex/PPExpressions.cpp
index 12f5084298..d8431827e9 100644
--- a/lib/Lex/PPExpressions.cpp
+++ b/lib/Lex/PPExpressions.cpp
@@ -237,35 +237,32 @@ static bool EvaluateValue(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
     PP.setCodeCompletionReached();
     PP.LexNonComment(PeekTok);
   }
-      
-  // If this token's spelling is a pp-identifier, check to see if it is
-  // 'defined' or if it is a macro.  Note that we check here because many
-  // keywords are pp-identifiers, so we can't check the kind.
-  if (IdentifierInfo *II = PeekTok.getIdentifierInfo()) {
-    // Handle "defined X" and "defined(X)".
-    if (II->isStr("defined"))
-      return EvaluateDefined(Result, PeekTok, DT, ValueLive, PP);
-
-    // If this identifier isn't 'defined' or one of the special
-    // preprocessor keywords and it wasn't macro expanded, it turns
-    // into a simple 0, unless it is the C++ keyword "true", in which case it
-    // turns into "1".
-    if (ValueLive &&
-        II->getTokenID() != tok::kw_true &&
-        II->getTokenID() != tok::kw_false)
-      PP.Diag(PeekTok, diag::warn_pp_undef_identifier) << II;
-    Result.Val = II->getTokenID() == tok::kw_true;
-    Result.Val.setIsUnsigned(false);  // "0" is signed intmax_t 0.
-    Result.setIdentifier(II);
-    Result.setRange(PeekTok.getLocation());
-    DT.IncludedUndefinedIds = (II->getTokenID() != tok::kw_true &&
-                               II->getTokenID() != tok::kw_false);
-    PP.LexNonComment(PeekTok);
-    return false;
-  }
 
   switch (PeekTok.getKind()) {
-  default:  // Non-value token.
+  default:
+    // If this token's spelling is a pp-identifier, check to see if it is
+    // 'defined' or if it is a macro.  Note that we check here because many
+    // keywords are pp-identifiers, so we can't check the kind.
+    if (IdentifierInfo *II = PeekTok.getIdentifierInfo()) {
+      // Handle "defined X" and "defined(X)".
+      if (II->isStr("defined"))
+        return EvaluateDefined(Result, PeekTok, DT, ValueLive, PP);
+
+      if (!II->isCPlusPlusOperatorKeyword()) {
+        // If this identifier isn't 'defined' or one of the special
+        // preprocessor keywords and it wasn't macro expanded, it turns
+        // into a simple 0
+        if (ValueLive)
+          PP.Diag(PeekTok, diag::warn_pp_undef_identifier) << II;
+        Result.Val = 0;
+        Result.Val.setIsUnsigned(false); // "0" is signed intmax_t 0.
+        Result.setIdentifier(II);
+        Result.setRange(PeekTok.getLocation());
+        DT.IncludedUndefinedIds = true;
+        PP.LexNonComment(PeekTok);
+        return false;
+      }
+    }
     PP.Diag(PeekTok, diag::err_pp_expr_bad_token_start_expr);
     return true;
   case tok::eod:
@@ -481,6 +478,14 @@ static bool EvaluateValue(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
       DT.State = DefinedTracker::DefinedMacro;
     return false;
   }
+  case tok::kw_true:
+  case tok::kw_false:
+    Result.Val = PeekTok.getKind() == tok::kw_true;
+    Result.Val.setIsUnsigned(false); // "0" is signed intmax_t 0.
+    Result.setIdentifier(PeekTok.getIdentifierInfo());
+    Result.setRange(PeekTok.getLocation());
+    PP.LexNonComment(PeekTok);
+    return false;
 
   // FIXME: Handle #assert
   }
diff --git a/lib/Lex/Preprocessor.cpp b/lib/Lex/Preprocessor.cpp
index 63f39524d1..d1dc8e1c00 100644
--- a/lib/Lex/Preprocessor.cpp
+++ b/lib/Lex/Preprocessor.cpp
@@ -712,14 +712,6 @@ bool Preprocessor::HandleIdentifier(Token &Identifier) {
     II.setIsFutureCompatKeyword(false);
   }
 
-  // C++ 2.11p2: If this is an alternative representation of a C++ operator,
-  // then we act as if it is the actual operator and not the textual
-  // representation of it.
-  if (II.isCPlusPlusOperatorKeyword() &&
-      !(getLangOpts().MSVCCompat &&
-        getSourceManager().isInSystemHeader(Identifier.getLocation())))
-    Identifier.setIdentifierInfo(nullptr);
-
   // If this is an extension token, diagnose its use.
   // We avoid diagnosing tokens that originate from macro definitions.
   // FIXME: This warning is disabled in cases where it shouldn't be,