RegExp bitmap test for word character.

src/ia32/regexp-macro-assembler-ia32.cc

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 //
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@@ skipping 521 matching lines @@
       // Compare original value to 0x2028 and 0x2029, using the already
       // computed (current_char ^ 0x01 - 0x0b). I.e., check for
       // 0x201d (0x2028 - 0x0b) or 0x201e.
       __ sub(Operand(eax), Immediate(0x2028 - 0x0b));
       __ cmp(eax, 0x2029 - 0x2028);
       BranchOrBacktrack(below_equal, on_no_match);
     }
     return true;
   }
   case 'w': {
-    Label done, check_digits;
-    __ cmp(Operand(current_character()), Immediate('9'));
-    __ j(less_equal, &check_digits);
-    __ cmp(Operand(current_character()), Immediate('_'));
-    __ j(equal, &done);
-    // Convert to lower case if letter.
-    __ mov(Operand(eax), current_character());
-    __ or_(eax, 0x20);
-    // check current character in range ['a'..'z'], nondestructively.
-    __ sub(Operand(eax), Immediate('a'));
-    __ cmp(Operand(eax), Immediate('z' - 'a'));
-    BranchOrBacktrack(above, on_no_match);
-    __ jmp(&done);
-    __ bind(&check_digits);
-    // Check current character in range ['0'..'9'].
-    __ cmp(Operand(current_character()), Immediate('0'));
-    BranchOrBacktrack(below, on_no_match);
-    __ bind(&done);
-
+    if (mode_ != ASCII) {
+      // Table is 128 bits, so all ASCII characters can be tested.

[Erik Corry, 2010/01/15 12:02:09]

bytes.

+      __ cmp(Operand(current_character()), Immediate('z'));
+      BranchOrBacktrack(above, on_no_match);
+    }
+    ASSERT_EQ(0, word_character_map[0]);  // Character '\0' is not a word char.

[Erik Corry, 2010/01/15 12:02:09]

Perhaps also assert that word_character_map['a'] is 255.

[Lasse Reichstein, 2010/01/18 09:56:52]

I'll put it in the comment at the table declaration that entries must be 0 or
255.
The important test here is that '\0' isn't a word character, so it doesn't
matter that:
  is_word_char(character) ::= (character & table[character]) != 0
gives false independently of the table.

+    ExternalReference word_map = ExternalReference::re_word_character_map();
+    __ test_b(current_character(),
+              Operand::StaticArray(current_character(), times_1, word_map));
+    BranchOrBacktrack(zero, on_no_match);
     return true;
   }
   case 'W': {
-    Label done, check_digits;
-    __ cmp(Operand(current_character()), Immediate('9'));
-    __ j(less_equal, &check_digits);
-    __ cmp(Operand(current_character()), Immediate('_'));
-    BranchOrBacktrack(equal, on_no_match);
-    // Convert to lower case if letter.
-    __ mov(Operand(eax), current_character());
-    __ or_(eax, 0x20);
-    // check current character in range ['a'..'z'], nondestructively.
-    __ sub(Operand(eax), Immediate('a'));
-    __ cmp(Operand(eax), Immediate('z' - 'a'));
-    BranchOrBacktrack(below_equal, on_no_match);
-    __ jmp(&done);
-    __ bind(&check_digits);
-    // Check current character in range ['0'..'9'].
-    __ cmp(Operand(current_character()), Immediate('0'));
-    BranchOrBacktrack(above_equal, on_no_match);
-    __ bind(&done);
+    Label done;
+    if (mode_ != ASCII) {
+      // Table is 128 bits, so all ASCII characters can be tested.

[Erik Corry, 2010/01/15 12:02:09]

bytes

+      __ cmp(Operand(current_character()), Immediate('z'));
+      __ j(above, &done);
+    }
+    ASSERT_EQ(0, word_character_map[0]);  // Character '\0' is not a word char.
+    ExternalReference word_map = ExternalReference::re_word_character_map();
+    __ test_b(current_character(),
+              Operand::StaticArray(current_character(), times_1, word_map));
+    BranchOrBacktrack(not_zero, on_no_match);
+    if (mode_ != ASCII) {
+      __ bind(&done);
+    }
     return true;
   }
   // Non-standard classes (with no syntactic shorthand) used internally.
   case '*':
     // Match any character.
     return true;
   case 'n': {
     // Match newlines (0x0a('\n'), 0x0d('\r'), 0x2028 or 0x2029).
     // The opposite of '.'.
     __ mov(Operand(eax), current_character());
@@ skipping 618 matching lines @@
     }
   }
 }
 
 
 #undef __
 
 #endif  // V8_NATIVE_REGEXP
 
 }}  // namespace v8::internal