MIPS: Regexp: Improve the speed that we scan for an initial point

src/mips/regexp-macro-assembler-mips.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 443 matching lines @@
 void RegExpMacroAssemblerMIPS::CheckNotCharacter(uint32_t c,
                                                 Label* on_not_equal) {
   BranchOrBacktrack(on_not_equal, ne, current_character(), Operand(c));
 }
 
 
 void RegExpMacroAssemblerMIPS::CheckCharacterAfterAnd(uint32_t c,
                                                      uint32_t mask,
                                                      Label* on_equal) {
   __ And(a0, current_character(), Operand(mask));
-  BranchOrBacktrack(on_equal, eq, a0, Operand(c));
+  Operand rhs = (c == 0) ? Operand(zero_reg) : Operand(c);
+  BranchOrBacktrack(on_equal, eq, a0, rhs);
 }
 
 
 void RegExpMacroAssemblerMIPS::CheckNotCharacterAfterAnd(uint32_t c,
                                                         uint32_t mask,
                                                         Label* on_not_equal) {
   __ And(a0, current_character(), Operand(mask));
-  BranchOrBacktrack(on_not_equal, ne, a0, Operand(c));
+  Operand rhs = (c == 0) ? Operand(zero_reg) : Operand(c);
+  BranchOrBacktrack(on_not_equal, ne, a0, rhs);
 }
 
 
 void RegExpMacroAssemblerMIPS::CheckNotCharacterAfterMinusAnd(
     uc16 c,
     uc16 minus,
     uc16 mask,
     Label* on_not_equal) {
   UNIMPLEMENTED_MIPS();
 }
@@ skipping 823 matching lines @@
 }
 
 
 #undef __
 
 #endif  // V8_INTERPRETED_REGEXP
 
 }}  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS