[tcf-dev] Disassembly Service logic with Symbols

["Wilson, David" <david.wilson@xxxxxxxxx>]

Hi All,

 

I am wondering if I could get some clarification on how the disassembly command (in the disassembly service, disassembly.c) is meant to deal with cases when symbols are loaded.

The behavior I have noticed:

 

Command: Disassembly disassemble “ContextID” Addr 1 {}

 

This will return us at least 1 instruction (even though we’ve only specified one byte).

 

Then, we continue to ask for more instructions e.g.:

 

Command: Disassembly disassemble “ContextID” Addr 500 {}

 

And this will return us instructions up to the given size.

 

 

However – we have noticed, with symbols loaded, that this will reach a “limit” on the size of instructions we can ask for (i.e. we reach a point where we cannot ask for more.

 

This means even if we ask for: Command: Disassembly disassemble “ContextID” Addr 1000 {}

 

We still get the same number of instructions returned.

 

 

This happens because of the following block:

 

if (sym_addr_ok && sym_size_ok &&

                    sym_addr <= buf_addr && sym_addr + sym_size > buf_addr &&

                    sym_addr + sym_size <= buf_addr + buf_size) {

                buf_size = sym_addr + sym_size - buf_addr;

                mem_size = (size_t)buf_size;

            }

 

I am wondering if this behavior is expected, and if so – what the purpose of it is.

 

Kind Regards

 

David Wilson

Intel Deutschland GmbH
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