Vector35
Remove dead partial stores of return registers when possible
Version and Platform (required):
- Binary Ninja Version: 4.2.6188-dev (ab61b8dc)
- OS: Windows 11
- OS Version: 23H2
- CPU Architecture: x86-64
Bug Description:
In function sub_180001160 of the attached binary, result is defined as a single variable, stored in rax, but before each return, the variable should be split and merged with the return value. Binary ninja correctly shows just return 0 and return 1, but the stores into RAX for the return values are still shown when they should be hidden.
Steps To Reproduce: Open the attached binary and let analysis finish.
Expected Behavior:
the stores into result before each of the returns should be hidden.
Screenshots/Video Recording:
Initial with return value changed to bool and reanalyzed:
Split into new variables (which binja warns could be incorrect):
Each new variable set to
bool, which finally removes the store:
Binary:
Source code of the function:
- https://github.com/Lachee/unity-named-pipes/blob/master/UnityNamedPipe.Native/connection_win.cpp#L17
Additional Information:
- The source code is also just one line instead of split with an if statement:
return handle != NULL && isOpened && handle != INVALID_HANDLE_VALUE; - The fully reversed function looks like this:
