3 files changed, 40 insertions, 4 deletions
diff --git a/clang/include/clang/AST/Expr.h b/clang/include/clang/AST/Expr.h
index 598f18937f9..11fa6cf6342 100644
--- a/clang/include/clang/AST/Expr.h
+++ b/clang/include/clang/AST/Expr.h
@@ -28,7 +28,6 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/Compiler.h"
-#include <cctype>
 
 namespace clang {
   class APValue;
diff --git a/clang/include/clang/Basic/CharInfo.h b/clang/include/clang/Basic/CharInfo.h
index f9b7b7311d0..2522face65e 100644
--- a/clang/include/clang/Basic/CharInfo.h
+++ b/clang/include/clang/Basic/CharInfo.h
@@ -10,6 +10,8 @@
 #ifndef CLANG_BASIC_CHARINFO_H
 #define CLANG_BASIC_CHARINFO_H
 
+#include "clang/Basic/LLVM.h"
+#include "llvm/ADT/StringRef.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/DataTypes.h"
 
@@ -157,6 +159,41 @@ LLVM_READONLY static inline bool isRawStringDelimBody(unsigned char c) {
                           CHAR_DIGIT|CHAR_UNDER|CHAR_RAWDEL)) != 0;
 }
 
+
+/// Converts the given ASCII character to its lowercase equivalent.
+///
+/// If the character is not an uppercase character, it is returned as is.
+LLVM_READONLY static inline char toLowercase(char c) {
+  if (isUppercase(c))
+    return c + 'a' - 'A';
+  return c;
+}
+
+/// Converts the given ASCII character to its uppercase equivalent.
+///
+/// If the character is not a lowercase character, it is returned as is.
+LLVM_READONLY static inline char toUppercase(char c) {
+  if (isLowercase(c))
+    return c + 'A' - 'a';
+  return c;
+}
+
+
+/// Return true if this is a valid ASCII identifier.
+///
+/// Note that this is a very simple check; it does not accept '$' or UCNs as
+/// valid identifier characters.
+LLVM_READONLY static inline bool isValidIdentifier(StringRef S) {
+  if (S.empty() || !isIdentifierHead(S[0]))
+    return false;
+
+  for (StringRef::iterator I = S.begin(), E = S.end(); I != E; ++I)
+    if (!isIdentifierBody(*I))
+      return false;
+
+  return true;
+}
+
 } // end namespace clang
 
 #endif
diff --git a/clang/include/clang/Lex/LiteralSupport.h b/clang/include/clang/Lex/LiteralSupport.h
index 7ffa328651f..b1430cc8051 100644
--- a/clang/include/clang/Lex/LiteralSupport.h
+++ b/clang/include/clang/Lex/LiteralSupport.h
@@ -15,13 +15,13 @@
 #ifndef CLANG_LITERALSUPPORT_H
 #define CLANG_LITERALSUPPORT_H
 
+#include "clang/Basic/CharInfo.h"
 #include "clang/Basic/LLVM.h"
 #include "clang/Basic/TokenKinds.h"
 #include "llvm/ADT/APFloat.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/DataTypes.h"
-#include <cctype>
 
 namespace clang {
 
@@ -101,7 +101,7 @@ private:
   /// SkipHexDigits - Read and skip over any hex digits, up to End.
   /// Return a pointer to the first non-hex digit or End.
   const char *SkipHexDigits(const char *ptr) {
-    while (ptr != ThisTokEnd && isxdigit(*ptr))
+    while (ptr != ThisTokEnd && isHexDigit(*ptr))
       ptr++;
     return ptr;
   }
@@ -117,7 +117,7 @@ private:
   /// SkipDigits - Read and skip over any digits, up to End.
   /// Return a pointer to the first non-hex digit or End.
   const char *SkipDigits(const char *ptr) {
-    while (ptr != ThisTokEnd && isdigit(*ptr))
+    while (ptr != ThisTokEnd && isDigit(*ptr))
       ptr++;
     return ptr;
   }