[clang] 9628cb1 - [NFC] Use higher level constructs to check for whitespace/newlines in the lexer

[via cfe-commits]

Author: serge-sans-paille
Date: 2021-03-15T18:27:19+01:00
New Revision: 9628cb1feef63d764c57fd0652016f9188000e2f

URL: https://github.com/llvm/llvm-project/commit/9628cb1feef63d764c57fd0652016f9188000e2f
DIFF: https://github.com/llvm/llvm-project/commit/9628cb1feef63d764c57fd0652016f9188000e2f.diff

LOG: [NFC] Use higher level constructs to check for whitespace/newlines in the lexer

It turns out that according to valgrind and perf, it's also slightly faster.

Differential Revision: https://reviews.llvm.org/D98637

Added: 
    

Modified: 
    clang/lib/Lex/Lexer.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Lex/Lexer.cpp b/clang/lib/Lex/Lexer.cpp
index e63574e306fb..75c0fb65f5b1 100644
--- a/clang/lib/Lex/Lexer.cpp
+++ b/clang/lib/Lex/Lexer.cpp
@@ -2061,7 +2061,7 @@ bool Lexer::LexAngledStringLiteral(Token &Result, const char *CurPtr) {
     if (C == '\\')
       C = getAndAdvanceChar(CurPtr, Result);
 
-    if (C == '\n' || C == '\r' ||                // Newline.
+    if (isVerticalWhitespace(C) ||               // Newline.
         (C == 0 && (CurPtr - 1 == BufferEnd))) { // End of file.
       // If the filename is unterminated, then it must just be a lone <
       // character.  Return this as such.
@@ -3208,10 +3208,10 @@ bool Lexer::LexTokenInternal(Token &Result, bool TokAtPhysicalStartOfLine) {
   const char *CurPtr = BufferPtr;
 
   // Small amounts of horizontal whitespace is very common between tokens.
-  if ((*CurPtr == ' ') || (*CurPtr == '\t')) {
-    ++CurPtr;
-    while ((*CurPtr == ' ') || (*CurPtr == '\t'))
+  if (isHorizontalWhitespace(*CurPtr)) {
+    do {
       ++CurPtr;
+    } while (isHorizontalWhitespace(*CurPtr));
 
     // If we are keeping whitespace and other tokens, just return what we just
     // skipped.  The next lexer invocation will return the token after the