Set the current context to the function's context when entering to LAP.

src/x64/macro-assembler-x64.cc

Index: src/x64/macro-assembler-x64.cc
diff --git a/src/x64/macro-assembler-x64.cc b/src/x64/macro-assembler-x64.cc
index 5371afcdfef0a9a7893ca818215b62064cec29d1..36d3f064a0a26f1a37307c32dbba3e8a55d8314f 100644
--- a/src/x64/macro-assembler-x64.cc
+++ b/src/x64/macro-assembler-x64.cc
@@ -4033,6 +4033,18 @@ Condition MacroAssembler::IsObjectNameType(Register heap_object,
   return below_equal;
 }
 
+void MacroAssembler::GetMapConstructor(Register result, Register map,
+                                       Register temp) {
+  Label done, loop;
+  movp(result, FieldOperand(map, Map::kConstructorOrBackPointerOffset));
+  bind(&loop);
+  JumpIfSmi(result, &done, Label::kNear);
+  CmpObjectType(result, MAP_TYPE, temp);
+  j(not_equal, &done, Label::kNear);
+  movp(result, FieldOperand(result, Map::kConstructorOrBackPointerOffset));
+  jmp(&loop);
+  bind(&done);
+}
 
 void MacroAssembler::SetCounter(StatsCounter* counter, int value) {
   if (FLAG_native_code_counters && counter->Enabled()) {