Hierarchy method renaming fails on classes with outdated opcodes JSR/RET

When remapping methods on small inputs, the method hierarchy is renamed successfully. When introducing a thousand or so extra/unrelated classes renaming the same method fails to update the hierarchy

Linked method renaming feature success is conditional

To Reproduce Steps to reproduce the behavior:

1. Compile recaf from src and then use the smaller jar as input.
2. Use Linked method renaming and rename me/coley/logging/Logger.write(Ljava/lang/String;)V to anything
   • It should rename, and so should me/coley/logging/ConsoleLogger.write(Ljava/lang/String;)V
3. Use the larger jar with dependencies as input.
4. Use Linked method renaming and rename me/coley/logging/Logger.write(Ljava/lang/String;)V to anything
   • It does not rename, and nor does me/coley/logging/ConsoleLogger.write(Ljava/lang/String;)V

[andrewleech]

Thanks for the suggestion, I’ve just started trying out recaf and so far love the work you’ve put into it!

[Col-E]

So the actual issue was there were certain classes in the jar that were compiled with an older version and hence contained older opcodes that are no longer supported. Recaf tried to generate stack-frames for the opcode which failed due to ASM’s implementation.

Possible future approaches:

• Plugin to replace JSR/RET opcodes so this does not happen
• Auto-detect when to not use COMPUTE_FRAMES even when the option is enabled