[regexp] implement case-insensitive unicode regexps.

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

Index: src/regexp/ia32/regexp-macro-assembler-ia32.cc
diff --git a/src/regexp/ia32/regexp-macro-assembler-ia32.cc b/src/regexp/ia32/regexp-macro-assembler-ia32.cc
index 6ef0f5fff6d7c8684035aac2fa5495b3a927376a..161219c87cfc201a4babd213fa47148e29a2885f 100644
--- a/src/regexp/ia32/regexp-macro-assembler-ia32.cc
+++ b/src/regexp/ia32/regexp-macro-assembler-ia32.cc
@@ -189,7 +189,7 @@ void RegExpMacroAssemblerIA32::CheckGreedyLoop(Label* on_equal) {
 
 
 void RegExpMacroAssemblerIA32::CheckNotBackReferenceIgnoreCase(
-    int start_reg, bool read_backward, Label* on_no_match) {
+    int start_reg, bool read_backward, bool unicode, Label* on_no_match) {
   Label fallthrough;
   __ mov(edx, register_location(start_reg));  // Index of start of capture
   __ mov(ebx, register_location(start_reg + 1));  // Index of end of capture
@@ -296,11 +296,18 @@ void RegExpMacroAssemblerIA32::CheckNotBackReferenceIgnoreCase(
     //   Address byte_offset1 - Address captured substring's start.
     //   Address byte_offset2 - Address of current character position.
     //   size_t byte_length - length of capture in bytes(!)
-    //   Isolate* isolate
+//   Isolate* isolate or 0 if unicode flag.
 
     // Set isolate.
-    __ mov(Operand(esp, 3 * kPointerSize),
-           Immediate(ExternalReference::isolate_address(isolate())));
+#ifdef V8_I18N_SUPPORT
+    if (unicode) {
+      __ mov(Operand(esp, 3 * kPointerSize), Immediate(0));
+    } else  // NOLINT
+#endif      // V8_I18N_SUPPORT
+    {
+      __ mov(Operand(esp, 3 * kPointerSize),
+             Immediate(ExternalReference::isolate_address(isolate())));
+    }
     // Set byte_length.
     __ mov(Operand(esp, 2 * kPointerSize), ebx);
     // Set byte_offset2.