[compiler] Generalize context load/store operations in code-stub-assembler.

src/code-stub-assembler.cc

Index: src/code-stub-assembler.cc
diff --git a/src/code-stub-assembler.cc b/src/code-stub-assembler.cc
index 660d57d61541535fb4fc9ce28dc427dda4a2e945..d7820d4662ee841d2199f4af13d48e5410fdab86 100644
--- a/src/code-stub-assembler.cc
+++ b/src/code-stub-assembler.cc
@@ -1264,6 +1264,13 @@ Node* CodeStubAssembler::LoadContextElement(Node* context, int slot_index) {
   return Load(MachineType::AnyTagged(), context, IntPtrConstant(offset));
 }
 
+Node* CodeStubAssembler::LoadContextElement(Node* context, Node* slot_index) {
+  Node* offset =
+      IntPtrAdd(WordShl(slot_index, kPointerSizeLog2),
+                IntPtrConstant(Context::kHeaderSize - kHeapObjectTag));
+  return Load(MachineType::AnyTagged(), context, offset);
+}
+
 Node* CodeStubAssembler::StoreContextElement(Node* context, int slot_index,
                                              Node* value) {
   int offset = Context::SlotOffset(slot_index);
@@ -1271,6 +1278,14 @@ Node* CodeStubAssembler::StoreContextElement(Node* context, int slot_index,
                value);
 }
 
+Node* CodeStubAssembler::StoreContextElement(Node* context, Node* slot_index,
+                                             Node* value) {
+  Node* offset =
+      IntPtrAdd(WordShl(slot_index, kPointerSizeLog2),
+                IntPtrConstant(Context::kHeaderSize - kHeapObjectTag));
+  return Store(MachineRepresentation::kTagged, context, offset, value);
+}
+
 Node* CodeStubAssembler::LoadNativeContext(Node* context) {
   return LoadContextElement(context, Context::NATIVE_CONTEXT_INDEX);
 }