Implement checked mode in new compiler.

runtime/vm/stub_code_x64.cc

Index: runtime/vm/stub_code_x64.cc
===================================================================
--- runtime/vm/stub_code_x64.cc	(revision 6541)
+++ runtime/vm/stub_code_x64.cc	(working copy)
@@ -1729,8 +1729,83 @@
 }
 
 
+// Check if an instance class is a subtype of class/interface using simple
+// superchain and interface array traversal. Does not take type parameters into
+// account.
+// RAX: instance (preserved)
+// RCX: class/interface to test against (is class of instance a subtype of it).
+//      (preserved).
+// Result in RBX: 1 is subtype, 0 maybe not.
+// Must preserve RDX.
+// Destroys RBX, R13, R10.
 void StubCode::GenerateIsRawSubTypeStub(Assembler* assembler) {
-  __ Unimplemented("IsRawSubType Stub");
+  const Immediate raw_null =
+      Immediate(reinterpret_cast<intptr_t>(Object::null()));
+  Label test_class, not_found, found, class_loaded_in_R10, smi_value;
+  __ EnterFrame(0);
+  __ testq(RAX, Immediate(kSmiTagMask));
+  __ j(ZERO, &smi_value, Assembler::kNearJump);
+  __ movq(R10, FieldAddress(RAX, Object::class_offset()));
+  __ jmp(&class_loaded_in_R10, Assembler::kNearJump);
+  __ Bind(&smi_value);
+  __ movq(R10, FieldAddress(CTX, Context::isolate_offset()));
+  __ movq(R10, Address(R10, Isolate::object_store_offset()));
+  __ movq(R10, Address(R10, ObjectStore::smi_class_offset()));
+  __ Bind(&class_loaded_in_R10);
+
+  __ movzxb(RBX, FieldAddress(RCX, Class::is_interface_offset()));
+  // Check if we are comparing against class or interface.
+  __ cmpq(RBX, Immediate(0));
+  __ j(EQUAL, &test_class, Assembler::kNearJump);
+
+  // Get interfaces array from instance class.
+  __ movq(RBX, FieldAddress(R10, Class::interfaces_offset()));
+  __ cmpq(RBX, raw_null);
+  __ j(EQUAL, &not_found, Assembler::kNearJump);
+  __ movq(R13, FieldAddress(RBX, Array::length_offset()));
+  // R13: array index.
+  // RBX: interface array.
+  // RCX: interface searched
+  Label array_loop;
+  __ Bind(&array_loop);
+  __ subq(R13, Immediate(Smi::RawValue(1)));
+  // __ cmpq(R13, Immediate(0));
+  __ j(LESS, &not_found, Assembler::kNearJump);
+  // R13 is Smi therefore TIMES_4 instead of TIMES_8.
+  // Get type from array.
+  __ movq(R10, FieldAddress(RBX, R13, TIMES_4, Array::data_offset()));
+  __ movq(R10, FieldAddress(R10, Type::type_class_offset()));
+  __ cmpq(R10, RCX);
+  __ j(EQUAL, &found, Assembler::kNearJump);
+  __ jmp(&array_loop, Assembler::kNearJump);
+
+  __ Bind(&not_found);
+  __ xorq(RBX, RBX);
+  __ LeaveFrame();
+  __ ret();
+
+  __ Bind(&found);
+  __ movq(RBX, Immediate(1));
+  __ LeaveFrame();
+  __ ret();
+
+  __ Bind(&test_class);
+  // RCX: test class.
+  __ cmpq(R10, RCX);
+  __ j(EQUAL, &found, Assembler::kNearJump);
+
+  // Check superclasses using a loop (faster than runtime call).
+  Label super_loop;
+  __ Bind(&super_loop);
+  // R10: class -> super.
+  __ movq(R10, FieldAddress(R10, Class::super_type_offset()));
+  // The supertype of Object is a null object.
+  __ cmpq(R10, raw_null);
+  __ j(EQUAL, &not_found, Assembler::kNearJump);
+  __ movq(R10, FieldAddress(R10, Type::type_class_offset()));
+  __ cmpq(RCX, R10);
+  __ j(NOT_EQUAL, &super_loop, Assembler::kNearJump);
+  __ jmp(&found, Assembler::kNearJump);
 }
 
 }  // namespace dart