IDA Python script to nop instructions that matches arbitrary assembly pattern
Fully functional in IDA Pro 7.7 with python 3.11.5. No tests were done in other IDA or Python versions.
While reversing software in IDA Pro, I've found that a specific code was making use of some specific junk assembly code patterns to trick the decompiler into wrong decompilation, repeatedly. To solve this issue I wrote an script to automate the detection of all the code that matches the pattern in the __text section of the binary and NOP them. It solved decompilation issues.
It is agnostic to architecture or disassembly flavor, it can match whatever assembly code pattern you write in any architecture, but 2 small changes are required when not dealing with ARM64 little-endian architecture. The NOP variable is assigned the value of 0x1F2003D5 or \x1F\x20\x03\xD5 which represents the NOP instruction for ARM64 architecture in little-endian, you can edit it to fit any other instruction of your like. Also the iteration through the __text section blob is stepping 4 bytes for every single instruction as all ARM64 instructions are 4 bytes only, you should edit the step size to fit your target architecture.
Go to IDA -> File -> Script File -> Select the script file and wait for it to run. It should patch all the patterns and show it's output in the Output Window.