Merge pull request #9565 from swiftlang/bugfix/lldb-objc-method-list-offset-fix-to-20240723

Michael137 · web-flow · commit 5b19506034a2 · 2024-11-11T16:08:02.000Z
[cherry-pick] [lldb][ObjC] Fix method list entry offset calculation
diff --git a/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCClassDescriptorV2.cpp b/lldb/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCClassDescriptorV2.cpp
@@ -394,7 +394,7 @@ bool ClassDescriptorV2::relative_list_entry_t::Read(Process *process,
   lldb::offset_t cursor = 0;
   uint64_t raw_entry = extractor.GetU64_unchecked(&cursor);
   m_image_index = raw_entry & 0xFFFF;
-  m_list_offset = (int64_t)(raw_entry >> 16);
+  m_list_offset = llvm::SignExtend64<48>(raw_entry >> 16);
   return true;
 }
 

Original file line number	Diff line number	Diff line change
`@@ -394,7 +394,7 @@ bool ClassDescriptorV2::relative_list_entry_t::Read(Process *process,`
`394`	`394`	`lldb::offset_t cursor = 0;`
`395`	`395`	`uint64_t raw_entry = extractor.GetU64_unchecked(&cursor);`
`396`	`396`	`m_image_index = raw_entry & 0xFFFF;`
`397`		`- m_list_offset = (int64_t)(raw_entry >> 16);`
	`397`	`+ m_list_offset = llvm::SignExtend64<48>(raw_entry >> 16);`
`398`	`398`	`return true;`
`399`	`399`	`}`
`400`	`400`