Revert of [regexp] Remove remainder of native RegExpExecStub

src/arm64/code-stubs-arm64.cc

Index: src/arm64/code-stubs-arm64.cc
diff --git a/src/arm64/code-stubs-arm64.cc b/src/arm64/code-stubs-arm64.cc
index b327773fc38994770e609e2ec07519a689aa37d3..ec00581566f28e75819e9c2df46fa70dd5342fde 100644
--- a/src/arm64/code-stubs-arm64.cc
+++ b/src/arm64/code-stubs-arm64.cc
@@ -1267,6 +1267,73 @@
   __ Ret();
 }
 
+void RegExpExecStub::Generate(MacroAssembler* masm) {
+#ifdef V8_INTERPRETED_REGEXP
+  // This case is handled prior to the RegExpExecStub call.
+  __ Abort(kUnexpectedRegExpExecCall);
+#else  // V8_INTERPRETED_REGEXP
+  // Isolates: note we add an additional parameter here (isolate pointer).
+  __ EnterExitFrame(false, x10, 1);
+  DCHECK(csp.Is(__ StackPointer()));
+
+  // We have 9 arguments to pass to the regexp code, therefore we have to pass
+  // one on the stack and the rest as registers.
+
+  // Note that the placement of the argument on the stack isn't standard
+  // AAPCS64:
+  // csp[0]: Space for the return address placed by DirectCEntryStub.
+  // csp[8]: Argument 9, the current isolate address.
+
+  __ Mov(x10, ExternalReference::isolate_address(isolate()));
+  __ Poke(x10, kPointerSize);
+
+  // Argument 1 (x0): Subject string.
+  CHECK(x0.is(RegExpExecDescriptor::StringRegister()));
+
+  // Argument 2 (x1): Previous index, already there.
+  CHECK(x1.is(RegExpExecDescriptor::LastIndexRegister()));
+
+  // Argument 3 (x2): Input start.
+  // Argument 4 (x3): Input end.
+  CHECK(x2.is(RegExpExecDescriptor::StringStartRegister()));
+  CHECK(x3.is(RegExpExecDescriptor::StringEndRegister()));
+
+  // Argument 5 (x4): static offsets vector buffer.
+  __ Mov(x4, ExternalReference::address_of_static_offsets_vector(isolate()));
+
+  // Argument 6 (x5): Set the number of capture registers to zero to force
+  // global regexps to behave as non-global. This stub is not used for global
+  // regexps.
+  __ Mov(x5, 0);
+
+  // Argument 7 (x6): Start (high end) of backtracking stack memory area.
+  ExternalReference address_of_regexp_stack_memory_address =
+      ExternalReference::address_of_regexp_stack_memory_address(isolate());
+  ExternalReference address_of_regexp_stack_memory_size =
+      ExternalReference::address_of_regexp_stack_memory_size(isolate());
+  __ Mov(x10, address_of_regexp_stack_memory_address);
+  __ Ldr(x10, MemOperand(x10));
+  __ Mov(x11, address_of_regexp_stack_memory_size);
+  __ Ldr(x11, MemOperand(x11));
+  __ Add(x6, x10, x11);
+
+  // Argument 8 (x7): Indicate that this is a direct call from JavaScript.
+  __ Mov(x7, 1);
+
+  // Locate the code entry and call it.
+  Register code_object = RegExpExecDescriptor::CodeRegister();
+  __ Add(code_object, code_object, Code::kHeaderSize - kHeapObjectTag);
+  DirectCEntryStub stub(isolate());
+  stub.GenerateCall(masm, code_object);
+
+  __ LeaveExitFrame(false, x10, true);
+
+  // Return the smi-tagged result.
+  __ SmiTag(x0);
+  __ Ret();
+#endif
+}
+
 
 static void CallStubInRecordCallTarget(MacroAssembler* masm, CodeStub* stub,
                                        Register argc, Register function,