citra/src/core/arm/arm_interface.h

// Copyright 2014 Citra Emulator Project
// Licensed under GPLv2
// Refer to the license.txt file included.  

#pragma once

#include "common/common.h"
#include "common/common_types.h"

/// Generic ARM11 CPU interface
class ARM_Interface {
public:
    ARM_Interface() {
        num_instructions_ = 0;
    }

    ~ARM_Interface() {
    }

    /// Step CPU by one instruction
    void Step() {
        ExecuteInstruction();
        num_instructions_++;
    }
 
    /**
     * Set the Program Counter to an address
     * @param addr Address to set PC to
     */
    virtual void SetPC(u32 addr) = 0;

    /*
     * Get the current Program Counter
     * @return Returns current PC
     */
    virtual u32 PC() = 0;

    /**
     * Get an ARM register
     * @param index Register index (0-15)
     * @return Returns the value in the register
     */
    virtual u32 Reg(int index) = 0;

    /**
     * Get the current CPSR register
     * @return Returns the value of the CPSR register
     */
    virtual u32 CPSR() = 0;  

    /**
     * Returns the number of clock ticks since the last rese
     * @return Returns number of clock ticks
     */
    virtual u64 GetTicks() = 0;

    /// Getter for num_instructions_
    u64 num_instructions() { return num_instructions_; }

private:
    
    /// Execture next instruction
    virtual void ExecuteInstruction() = 0;

    u64 num_instructions_;  ///< Number of instructions executed

    DISALLOW_COPY_AND_ASSIGN(ARM_Interface);
};