Using the Delegation System

Using the Delegation System#

The Moira class defines various delegation functions that are triggered on specific events. These functions are declared as virtual and have empty default implementations. A subclassed CPU can override them to react to the corresponding events.

State Delegates#

The following functions are called when the CPU enters specific states:

  • void cpuDidReset()

    Invoked at the end of the reset() routine.

  • void cpuDidHalt()

    Called when the CPU is halted, e.g., after a double-fault.

Instruction Delegates#

These functions are invoked at the start and end of selected instruction handlers:

  • void willExecute(const char *func, Instr I, Mode M, Size S, u16 opcode)

    Called at the beginning of selected instruction handlers. The instructions are defined by the WILL_EXECUTE macro in MoiraConfig.h. The default implementation looks as follows:

    #define MOIRA_WILL_EXECUTE I == Instr::STOP || I == Instr::TAS || I == Instr::BKPT

  • void didExecute(const char *func, Instr I, Mode M, Size S, u16 opcode)

    Called at the end of selected instruction handlers. The instructions are defined by the DID_EXECUTE macro in MoiraConfig.h. The default implementation looks as follows:

    #define MOIRA_DID_EXECUTE I == Instr::RESET

Exception Delegates#

  • void willExecute(ExceptionType exc, u16 vector)

    Called at the start of exception processing.

  • void didExecute(ExceptionType exc, u16 vector)

    Called at the end of exception processing.

  • void willInterrupt(u8 level)

    Called at the start of interrupt processing.

  • void didJumpToVector(int nr, u32 addr)

    Called after the program counter jumps to the exception handler.

Cache Register Delegates (68020 Only)#

These functions track changes to cache-related registers:

  • void didChangeCACR(u32 value)

    Called when the CACR (Cache Control Register) is modified.

  • void didChangeCAAR(u32 value)

    Called when the CAAR (Cache Address Register) is modified.

Debugger Delegates#

These functions signal debug events:

  • void didReachSoftstop(u32 addr)

    Called when a soft stop is reached.

  • void didReachBreakpoint(u32 addr)

    Called when a breakpoint is hit.

  • void didReachWatchpoint(u32 addr)

    Called when a watchpoint is hit.

  • void didReachCatchpoint(u8 vector)

    Called when a catchpoint is hit.

  • void didReachSoftwareTrap(u32 addr)

    Called when a software trap is hit.

Contents