Unify jmp and br behaviour #69
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When
init_state.inspect.b('exit', when=angr.BP_BEFORE, action=check_jump)
def check_jump(state):
addr = state.regs.ip
For jmp, jz, ... type instructions 'addr' will contain the value of ip before execution of the jmp instruction as they only execute self.jump(...) (https://github.com/angr/angr-platforms/blob/master/angr_platforms/msp430/instrs_msp430.py#L933)
For a branch instruction https://github.com/angr/angr-platforms/blob/master/angr_platforms/msp430/instrs_msp430.py#L660-L661 also the src will be returned which will trigger an immediate commit (https://github.com/angr/pyvex/blob/master/pyvex/lifting/util/instr_helper.py#L132-L134).
In the example above the br instruction will thus immediately affect the 'addr' as it will contain the ip where the br already occurred (so 'addr' will contain the ip after the br)
Fix Lint issue?
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Example
For jmp, jz, ... instructions 'addr' will contain the value of ip BEFORE THE JMP instruction as they only execute self.jump(...) (https://github.com/angr/angr-platforms/blob/master/angr_platforms/msp430/instrs_msp430.py#L933)
For a branch instruction https://github.com/angr/angr-platforms/blob/master/angr_platforms/msp430/instrs_msp430.py#L660-L661, a value (src) will be returned, which will trigger an immediate commit (https://github.com/angr/pyvex/blob/master/pyvex/lifting/util/instr_helper.py#L132-L134).
In the example above, the br instruction will thus immediately commit the result to the ip, so the 'addr' will contain the ip AFTER THE BR instruction (so 'addr' will contain the ip after the br)