As shown in the picture below, IDA PRO (6.8) knows to recognize that al and eax are referencing the same register.
Given two operands in IDA Python (i.e. by idc.GetOpnd(..)), how can I find that they are referencing the same register?
Build a dictionary like this:
{ "rax":"rax", "eax":"rax", "ax":"rax" ... }
You can start from the dictionaries contained in https://github.com/angr/archinfo and change it.
EAXis the full 32-bit value,ALis the lower 8 bits whereasAHis the higher 8 bits – Megabeets Jan 30 '18 at 19:52EAX,AH,ALare part of the same register, and if there's a IDA Python function that could tell me that? As you can see in the picture, choosingEAXmakeALbe highlighted too, meaning that there's some king of way that IDA connects between them behind the scenes. – macro_controller Jan 31 '18 at 8:11