X87: [regexp] implement case-insensitive unicode regexps.

  port a2baaaac (r33538)

  original commit message:

BUG=

Review URL: https://codereview.chromium.org/1644863002

Cr-Commit-Position: refs/heads/master@{#33568}

src/regexp/x87/regexp-macro-assembler-x87.cc

@@ -187,9 +187,8 @@ void RegExpMacroAssemblerX87::CheckGreedyLoop(Label* on_equal) {
   __ bind(&fallthrough);
 }
 
-
 void RegExpMacroAssemblerX87::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 +295,18 @@ void RegExpMacroAssemblerX87::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.
+#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.

src/regexp/x87/regexp-macro-assembler-x87.h

@@ -37,7 +37,7 @@ class RegExpMacroAssemblerX87: public NativeRegExpMacroAssembler {
   virtual void CheckNotBackReference(int start_reg, bool read_backward,
                                      Label* on_no_match);
   virtual void CheckNotBackReferenceIgnoreCase(int start_reg,
-                                               bool read_backward,
+                                               bool read_backward, bool unicode,
                                                Label* on_no_match);
   virtual void CheckNotCharacter(uint32_t c, Label* on_not_equal);
   virtual void CheckNotCharacterAfterAnd(uint32_t c,