1.1 --- a/src/sh4/sh4core.c	Tue Dec 12 09:18:47 2006 +0000
     1.2 +++ b/src/sh4/sh4core.c	Tue Dec 12 09:20:25 2006 +0000
     1.3 @@ -1,5 +1,5 @@
     1.4  /**
     1.5 - * $Id: sh4core.c,v 1.33 2006-09-26 11:09:13 nkeynes Exp $
     1.6 + * $Id: sh4core.c,v 1.34 2006-12-12 09:20:25 nkeynes Exp $
     1.7   * 
     1.8   * SH4 emulation core, and parent module for all the SH4 peripheral
     1.9   * modules.
    1.10 @@ -95,6 +95,8 @@
    1.11  
    1.12  static struct breakpoint_struct sh4_breakpoints[MAX_BREAKPOINTS];
    1.13  static int sh4_breakpoint_count = 0;
    1.14 +static uint16_t *sh4_icache = NULL;
    1.15 +static uint32_t sh4_icache_addr = 0;
    1.16  
    1.17  void sh4_set_breakpoint( uint32_t pc, int type )
    1.18  {
    1.19 @@ -142,22 +144,31 @@
    1.20  	    sh4r.sh4_state = SH4_STATE_RUNNING;;
    1.21      }
    1.22  
    1.23 -    for( sh4r.slice_cycle = 0; sh4r.slice_cycle < nanosecs; sh4r.slice_cycle += sh4_cpu_period ) {
    1.24 -	if( !sh4_execute_instruction() )
    1.25 -	    break;
    1.26 -#ifdef ENABLE_DEBUG_MODE
    1.27 -	for( i=0; i<sh4_breakpoint_count; i++ ) {
    1.28 -	    if( sh4_breakpoints[i].address == sh4r.pc ) {
    1.29 +    if( sh4_breakpoint_count == 0 ) {
    1.30 +	for( sh4r.slice_cycle = 0; sh4r.slice_cycle < nanosecs; sh4r.slice_cycle += sh4_cpu_period ) {
    1.31 +	    if( !sh4_execute_instruction() ) {
    1.32  		break;
    1.33  	    }
    1.34  	}
    1.35 -	if( i != sh4_breakpoint_count ) {
    1.36 -	    dreamcast_stop();
    1.37 -	    if( sh4_breakpoints[i].type == BREAK_ONESHOT )
    1.38 -		sh4_clear_breakpoint( sh4r.pc, BREAK_ONESHOT );
    1.39 -	    break;
    1.40 +    } else {
    1.41 +
    1.42 +	for( sh4r.slice_cycle = 0; sh4r.slice_cycle < nanosecs; sh4r.slice_cycle += sh4_cpu_period ) {
    1.43 +	    if( !sh4_execute_instruction() )
    1.44 +		break;
    1.45 +#ifdef ENABLE_DEBUG_MODE
    1.46 +	    for( i=0; i<sh4_breakpoint_count; i++ ) {
    1.47 +		if( sh4_breakpoints[i].address == sh4r.pc ) {
    1.48 +		    break;
    1.49 +		}
    1.50 +	    }
    1.51 +	    if( i != sh4_breakpoint_count ) {
    1.52 +		dreamcast_stop();
    1.53 +		if( sh4_breakpoints[i].type == BREAK_ONESHOT )
    1.54 +		    sh4_clear_breakpoint( sh4r.pc, BREAK_ONESHOT );
    1.55 +		break;
    1.56 +	    }
    1.57 +#endif	
    1.58  	}
    1.59 -#endif	
    1.60      }
    1.61  
    1.62      /* If we aborted early, but the cpu is still technically running,
    1.63 @@ -426,7 +437,24 @@
    1.64  	sh4r.new_pc = sh4r.pc + 2;
    1.65      }
    1.66      CHECKRALIGN16(pc);
    1.67 -    ir = MEM_READ_WORD(pc);
    1.68 +
    1.69 +    /* Read instruction */
    1.70 +    uint32_t pageaddr = pc >> 12;
    1.71 +    if( sh4_icache != NULL && pageaddr == sh4_icache_addr ) {
    1.72 +	ir = sh4_icache[(pc&0xFFF)>>1];
    1.73 +    } else {
    1.74 +	sh4_icache = (uint16_t *)mem_get_page(pc);
    1.75 +	if( ((uint32_t)sh4_icache) < MAX_IO_REGIONS ) {
    1.76 +	    /* If someone's actually been so daft as to try to execute out of an IO
    1.77 +	     * region, fallback on the full-blown memory read
    1.78 +	     */
    1.79 +	    sh4_icache = NULL;
    1.80 +	    ir = MEM_READ_WORD(pc);
    1.81 +	} else {
    1.82 +	    sh4_icache_addr = pageaddr;
    1.83 +	    ir = sh4_icache[(pc&0xFFF)>>1];
    1.84 +	}
    1.85 +    }
    1.86      sh4r.icount++;
    1.87      
    1.88      switch( (ir&0xF000)>>12 ) {