Fix white space matching in latin-1 strings wrt \u00a0.

src/x64/regexp-macro-assembler-x64.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 622 matching lines @@
 bool RegExpMacroAssemblerX64::CheckSpecialCharacterClass(uc16 type,
                                                          Label* on_no_match) {
   // Range checks (c in min..max) are generally implemented by an unsigned
   // (c - min) <= (max - min) check, using the sequence:
   //   lea(rax, Operand(current_character(), -min)) or sub(rax, Immediate(min))
   //   cmp(rax, Immediate(max - min))
   switch (type) {
   case 's':
     // Match space-characters
     if (mode_ == ASCII) {
-      // ASCII space characters are '\t'..'\r' and ' '.
+      // One byte space characters are '\t'..'\r', ' ' and \u00a0.
       Label success;
       __ cmpl(current_character(), Immediate(' '));
-      __ j(equal, &success);
+      __ j(equal, &success, Label::kNear);
       // Check range 0x09..0x0d
       __ lea(rax, Operand(current_character(), -'\t'));
       __ cmpl(rax, Immediate('\r' - '\t'));
-      BranchOrBacktrack(above, on_no_match);
+      __ j(below_equal, &success, Label::kNear);
+      // \u00a0 (NBSP).
+      __ cmpl(rax, Immediate(0x00a0 - '\t'));
+      BranchOrBacktrack(not_equal, on_no_match);
       __ bind(&success);
       return true;
     }
     return false;
   case 'S':
-    // Match non-space characters.
-    if (mode_ == ASCII) {
-      // ASCII space characters are '\t'..'\r' and ' '.
-      __ cmpl(current_character(), Immediate(' '));
-      BranchOrBacktrack(equal, on_no_match);
-      __ lea(rax, Operand(current_character(), -'\t'));
-      __ cmpl(rax, Immediate('\r' - '\t'));
-      BranchOrBacktrack(below_equal, on_no_match);
-      return true;
-    }
+    // The emitted code for generic character classes is good enough.
     return false;
   case 'd':
     // Match ASCII digits ('0'..'9')
     __ lea(rax, Operand(current_character(), -'0'));
     __ cmpl(rax, Immediate('9' - '0'));
     BranchOrBacktrack(above, on_no_match);
     return true;
   case 'D':
     // Match non ASCII-digits
     __ lea(rax, Operand(current_character(), -'0'));
@@ skipping 868 matching lines @@
   }
 }
 
 #undef __
 
 #endif  // V8_INTERPRETED_REGEXP
 
 }}  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64