src: use 24 as default for kHeaderSize

mmarchini · mmarchini · commit b30cf41a1777 · 2020-01-21T14:14:37.000-08:00
PR-URL: #330 Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com> Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
diff --git a/src/llv8-constants.cc b/src/llv8-constants.cc
@@ -501,7 +501,7 @@ void DescriptorArray::Load() {
   kFirstIndex = LoadOptionalConstant({"prop_idx_first"}, 0);
   kSize = LoadConstant({"prop_desc_size"});
   kHeaderSize = LoadOptionalConstant(
-      {"class_DescriptorArray__header_size__uintptr_t"}, 0);
+      {"class_DescriptorArray__header_size__uintptr_t"}, 24);
 }
 
 
diff --git a/src/llv8-inl.h b/src/llv8-inl.h
@@ -889,7 +889,7 @@ inline T DescriptorArray::Get(int index, int64_t offset) {
   if (v8()->descriptor_array()->kFirstIndex.Loaded()) {
     return FixedArray::Get<T>(
         *(v8()->descriptor_array()->kFirstIndex) + index + offset, err);
-  } else if (v8()->descriptor_array()->kHeaderSize.Loaded()) {
+  } else if (v8()->descriptor_array()->kHeaderSize.Check()) {
     index *= v8()->common()->kPointerSize;
     index += *(v8()->descriptor_array()->kHeaderSize);
     index += (v8()->common()->kPointerSize * offset);

Original file line number	Diff line number	Diff line change
`@@ -501,7 +501,7 @@ void DescriptorArray::Load() {`
`501`	`501`	`kFirstIndex = LoadOptionalConstant({"prop_idx_first"}, 0);`
`502`	`502`	`kSize = LoadConstant({"prop_desc_size"});`
`503`	`503`	`kHeaderSize = LoadOptionalConstant(`
`504`		`- {"class_DescriptorArray__header_size__uintptr_t"}, 0);`
	`504`	`+ {"class_DescriptorArray__header_size__uintptr_t"}, 24);`
`505`	`505`	`}`
`506`	`506`
`507`	`507`