[Interpreter] Add support for global declarations and load/store of global variables

src/compiler/interpreter-assembler.cc

Index: src/compiler/interpreter-assembler.cc
diff --git a/src/compiler/interpreter-assembler.cc b/src/compiler/interpreter-assembler.cc
index ca6c6134ed26f840742982aa633ecfce58befafc..d8f7990b3b2075b806712eb759149bcc07c419a5 100644
--- a/src/compiler/interpreter-assembler.cc
+++ b/src/compiler/interpreter-assembler.cc
@@ -274,14 +274,11 @@ Node* InterpreterAssembler::LoadObjectField(Node* object, int offset) {
 }
 
 
-Node* InterpreterAssembler::LoadContextSlot(Node* context, int slot_index) {
-  return raw_assembler_->Load(kMachAnyTagged, context,
-                              IntPtrConstant(Context::SlotOffset(slot_index)));
-}
-
-
-Node* InterpreterAssembler::LoadContextSlot(int slot_index) {
-  return LoadContextSlot(ContextTaggedPointer(), slot_index);
+Node* InterpreterAssembler::LoadContextSlot(Node* context, Node* slot_index) {
+  Node* offset =
+      IntPtrAdd(WordShl(slot_index, kPointerSizeLog2),
+                Int32Constant(Context::kHeaderSize - kHeapObjectTag));
+  return raw_assembler_->Load(kMachAnyTagged, context, offset);
 }