[interpreter] Add fast path for dynamic global lookups

src/interpreter/bytecode-array-builder.h

Index: src/interpreter/bytecode-array-builder.h
diff --git a/src/interpreter/bytecode-array-builder.h b/src/interpreter/bytecode-array-builder.h
index eacd35b09d58661a408168851caf077c76052003..2dff52ef4e199b40cd85dd15c7b88208a7916157 100644
--- a/src/interpreter/bytecode-array-builder.h
+++ b/src/interpreter/bytecode-array-builder.h
@@ -138,6 +138,13 @@ class BytecodeArrayBuilder final : public ZoneObject {
                                               TypeofMode typeof_mode,
                                               int slot_index, int depth);
 
+  // Lookup the variable with |name|, which has its feedback in |feedback_slot|
+  // and is known to be global if not shadowed by a context extension somewhere
+  // up to |depth| in that context chain.
+  BytecodeArrayBuilder& LoadLookupGlobalSlot(const Handle<String> name,
+                                             TypeofMode typeof_mode,
+                                             int feedback_slot, int depth);
+
   // Store value in the accumulator into the variable with |name|.
   BytecodeArrayBuilder& StoreLookupSlot(const Handle<String> name,
                                         LanguageMode language_mode);