Eagerly resolve the spelling location of the tokens in a definition
of a macro.  Since these tokens may themselves be from macro 
expansions, we need to resolve down to the spelling loc when the
macro ends up being instantiated.  Instead of resolving this for
each token expanded from the macro definition, just do it once when
the macro is defined.  This speeds up clang on c99-intconst-1.c from
2.66s to 2.43s (9.5%), reducing the FileID lookups from 407244 linear and
114175649 binary to 2529040 linear and 64771121 binary.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@62993 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/PPDirectives.cpp b/lib/Lex/PPDirectives.cpp
index ef26aeb..ec5b67f 100644
--- a/lib/Lex/PPDirectives.cpp
+++ b/lib/Lex/PPDirectives.cpp
@@ -991,6 +991,12 @@
   if (MI->isObjectLike()) {
     // Object-like macros are very simple, just read their body.
     while (Tok.isNot(tok::eom)) {
+      // If this token has a virtual location, resolve it down to its spelling
+      // location.  This is not strictly needed, but avoids extra resolutions
+      // for macros that are expanded frequently.
+      if (!Tok.getLocation().isFileID())
+        Tok.setLocation(SourceMgr.getSpellingLoc(Tok.getLocation()));
+      
       MI->AddTokenToBody(Tok);
       // Get the next token of the macro.
       LexUnexpandedToken(Tok);
@@ -1000,6 +1006,12 @@
     // Otherwise, read the body of a function-like macro.  This has to validate
     // the # (stringize) operator.
     while (Tok.isNot(tok::eom)) {
+      // If this token has a virtual location, resolve it down to its spelling
+      // location.  This is not strictly needed, but avoids extra resolutions
+      // for macros that are expanded frequently.
+      if (!Tok.getLocation().isFileID())
+        Tok.setLocation(SourceMgr.getSpellingLoc(Tok.getLocation()));
+      
       MI->AddTokenToBody(Tok);
 
       // Check C99 6.10.3.2p1: ensure that # operators are followed by macro