feat: add op counter

[DoTheBestToGetTheBest]

related with #20

[mattsse]

@sslivkoff what should opcode_gas

the total gas cost per opcode * count?

[DoTheBestToGetTheBest]

@mattsse does it look good to you ?

[DoTheBestToGetTheBest]

the total gas cost per opcode * count?

I was thinking of mapping each opcode to its constant gas value. Then, when the final opcode result is mapped, I would simply multiply the constant gas by the number of repetitions of that opcode. but this implementation seems inefficient, doesn't it ?

[DoTheBestToGetTheBest]

or it may be some funciton that can calculate the gas?

@sslivkoff what should opcode_gas

the total gas cost per opcode * count?

i tried to use the look up table from revm but it doesn't work it return for some opcode gas 0 and for some good value and for others false value

   fn step(&mut self, interp: &mut Interpreter, _context: &mut EvmContext<DB>) {
   
        let opcode_val = interp.current_opcode();
        let opcode =
            OpCode::new(opcode_val).unwrap_or_else(|| unsafe { OpCode::new_unchecked(opcode_val) });

  
        *self.opcode_counts.entry(opcode).or_insert(0) += 1;

        let spec_id = revm::primitives::specification::SpecId::SHANGHAI;
        let gas_info =
            revm::interpreter::instructions::opcode::spec_opcode_gas(spec_id)[opcode_val as usize];

        let opcode_gas = gas_info.get_gas() as u64;

        *self.opcode_gas.entry(opcode).or_insert(0) += opcode_gas;
    }
}```

[sslivkoff]

@sslivkoff what should opcode_gas

the total gas cost per opcode * count?

afaui the same op-code can cost different amounts of gas depending on context and depending on input arguments

so ideally it would be the sum of each opcode ocurrence but this would not be a simple multiplication

[sslivkoff]

there's also a bit of complication on contract calls returning whatever amount of spare unused gas they do not use

ideally want a situation where the sum of opcode gas entries equals the total amount of gas used by the transaction

might need to do some interesting nested gas accounting to make this happen given the various types of gas refunds

[mattsse]

let's also make the fields pub so they can be consumed easily

[DoTheBestToGetTheBest]

let's also make the fields pub so they can be consumed easily

no problem!

[DoTheBestToGetTheBest]

@mattsse does it look goods to you ?

[mattsse]

I few nits,

this could also use a helper function that returns an iterator over all opcodes and their count+gas (opcode, (u64,u64))

[DoTheBestToGetTheBest]

I few nits,

this could also use a helper function that returns an iterator over all opcodes and their count+gas (opcode, (u64,u64))

thanks, i hope this time look good to you :)

[mattsse]

lgtm