[regexp] implement case-insensitive unicode regexps.

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

Index: src/regexp/x64/regexp-macro-assembler-x64.cc
diff --git a/src/regexp/x64/regexp-macro-assembler-x64.cc b/src/regexp/x64/regexp-macro-assembler-x64.cc
index 286f159cc8e5ac4d04416e6a2f32c7aec735aa06..549ddae05e9580062f7c93ebd5542623164886c2 100644
--- a/src/regexp/x64/regexp-macro-assembler-x64.cc
+++ b/src/regexp/x64/regexp-macro-assembler-x64.cc
@@ -203,7 +203,7 @@ void RegExpMacroAssemblerX64::CheckGreedyLoop(Label* on_equal) {
 
 
 void RegExpMacroAssemblerX64::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;
   ReadPositionFromRegister(rdx, start_reg);  // Offset of start of capture
   ReadPositionFromRegister(rbx, start_reg + 1);  // Offset of end of capture
@@ -308,8 +308,10 @@ void RegExpMacroAssemblerX64::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.
 #ifdef _WIN64
+    DCHECK(rcx.is(arg_reg_1));
+    DCHECK(rdx.is(arg_reg_2));
     // Compute and set byte_offset1 (start of capture).
     __ leap(rcx, Operand(rsi, rdx, times_1, 0));
     // Set byte_offset2.
@@ -317,11 +319,9 @@ void RegExpMacroAssemblerX64::CheckNotBackReferenceIgnoreCase(
     if (read_backward) {
       __ subq(rdx, rbx);
     }
-    // Set byte_length.
-    __ movp(r8, rbx);
-    // Isolate.
-    __ LoadAddress(r9, ExternalReference::isolate_address(isolate()));
 #else  // AMD64 calling convention
+    DCHECK(rdi.is(arg_reg_1));
+    DCHECK(rsi.is(arg_reg_2));
     // Compute byte_offset2 (current position = rsi+rdi).
     __ leap(rax, Operand(rsi, rdi, times_1, 0));
     // Compute and set byte_offset1 (start of capture).
@@ -331,11 +331,19 @@ void RegExpMacroAssemblerX64::CheckNotBackReferenceIgnoreCase(
     if (read_backward) {
       __ subq(rsi, rbx);
     }
+#endif  // _WIN64
+
     // Set byte_length.
-    __ movp(rdx, rbx);
+    __ movp(arg_reg_3, rbx);
     // Isolate.
-    __ LoadAddress(rcx, ExternalReference::isolate_address(isolate()));
-#endif
+#ifdef V8_I18N_SUPPORT
+    if (unicode) {
+      __ movp(arg_reg_4, Immediate(0));
+    } else  // NOLINT
+#endif      // V8_I18N_SUPPORT
+    {
+      __ LoadAddress(arg_reg_4, ExternalReference::isolate_address(isolate()));
+    }
 
     { // NOLINT: Can't find a way to open this scope without confusing the
       // linter.