I am modelling a custom MOV instruction in the X86 architecture in the gem5 simulator, to test its implementation on the simulator, I need to compile my C code using inline assembly to create a binary file. But since it a custom instruction which has not been implemented in the GCC compiler, the compiler will throw out an error. I know one way is to extend the GCC compiler to accept my custom X86 instruction, but I do not want to do it as it is more time consuming(but will do it afterwards).
As a temporary hack (just to check if my implementation is worth it or not). I want to edit an already MOV instruction while changing its underlying "micro ops" in the simulator so as to trick the GCC to accept my "custom" instruction and compile.
As they are many types of MOV instructions which are available in the x86 architecture. As they are various MOV Instructions in the 86 architecture reference.
Therefore coming to my question, which MOV instruction is the least used and that I can edit its underlying micro-ops. Assuming my workload just includes integers i.e. most probably wont be using the xmm and mmx registers and my instructions mirrors the same implementation of a MOV instruction.