Question about control flow graph for synchronized statement

[ljcppp]

Question about control flow graph for synchronized statement

[msridhar]

I'm going to go ahead and close this as I'm pretty confident in the explanation above, but if you have further questions, please add another comment.

[msridhar]

I think the red edge corresponds to the case where the monitorenter does not succeed due to an NPE. I'm not sure about the green path, need to dig a bit more. Thanks for the report!

[msridhar]

You can see that there are two monitorexit instructions in the generated bytecode for your example:

https://gcc.godbolt.org/z/ffvjWEEMb

So I think the green path corresponds to bytecode that tries to catch any exception that gets thrown in the synchronized block and then run monitorexit before re-throwing the exception. It makes more sense in this example:

https://gcc.godbolt.org/z/9aKsx9xnK

So, in short, both the red and green cases correspond to exceptions where the corresponding monitorenter or monitorexit either did not execute or did not complete successfully. Does that make sense?