Initial creation of sourceware repository

1 files changed, 0 insertions, 1004 deletions

diff --git a/gdb/m68k-stub.c b/gdb/m68k-stub.c
deleted file mode 100644
index 66398b3..0000000
--- a/gdb/m68k-stub.c
+++ /dev/null
@@ -1,1004 +0,0 @@
-/****************************************************************************
-
-		THIS SOFTWARE IS NOT COPYRIGHTED  
-   
-   HP offers the following for use in the public domain.  HP makes no
-   warranty with regard to the software or it's performance and the 
-   user accepts the software "AS IS" with all faults.
-
-   HP DISCLAIMS ANY WARRANTIES, EXPRESS OR IMPLIED, WITH REGARD
-   TO THIS SOFTWARE INCLUDING BUT NOT LIMITED TO THE WARRANTIES
-   OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
-
-****************************************************************************/
-
-/****************************************************************************
- *  Header: remcom.c,v 1.34 91/03/09 12:29:49 glenne Exp $                   
- *
- *  Module name: remcom.c $  
- *  Revision: 1.34 $
- *  Date: 91/03/09 12:29:49 $
- *  Contributor:     Lake Stevens Instrument Division$
- *  
- *  Description:     low level support for gdb debugger. $
- *
- *  Considerations:  only works on target hardware $
- *
- *  Written by:      Glenn Engel $
- *  ModuleState:     Experimental $ 
- *
- *  NOTES:           See Below $
- * 
- *  To enable debugger support, two things need to happen.  One, a
- *  call to set_debug_traps() is necessary in order to allow any breakpoints
- *  or error conditions to be properly intercepted and reported to gdb.
- *  Two, a breakpoint needs to be generated to begin communication.  This
- *  is most easily accomplished by a call to breakpoint().  Breakpoint()
- *  simulates a breakpoint by executing a trap #1.  The breakpoint instruction
- *  is hardwired to trap #1 because not to do so is a compatibility problem--
- *  there either should be a standard breakpoint instruction, or the protocol
- *  should be extended to provide some means to communicate which breakpoint
- *  instruction is in use (or have the stub insert the breakpoint).
- *  
- *  Some explanation is probably necessary to explain how exceptions are
- *  handled.  When an exception is encountered the 68000 pushes the current
- *  program counter and status register onto the supervisor stack and then
- *  transfers execution to a location specified in it's vector table.
- *  The handlers for the exception vectors are hardwired to jmp to an address
- *  given by the relation:  (exception - 256) * 6.  These are decending 
- *  addresses starting from -6, -12, -18, ...  By allowing 6 bytes for
- *  each entry, a jsr, jmp, bsr, ... can be used to enter the exception 
- *  handler.  Using a jsr to handle an exception has an added benefit of
- *  allowing a single handler to service several exceptions and use the
- *  return address as the key differentiation.  The vector number can be
- *  computed from the return address by [ exception = (addr + 1530) / 6 ].
- *  The sole purpose of the routine _catchException is to compute the
- *  exception number and push it on the stack in place of the return address.
- *  The external function exceptionHandler() is
- *  used to attach a specific handler to a specific m68k exception.
- *  For 68020 machines, the ability to have a return address around just
- *  so the vector can be determined is not necessary because the '020 pushes an
- *  extra word onto the stack containing the vector offset
- * 
- *  Because gdb will sometimes write to the stack area to execute function
- *  calls, this program cannot rely on using the supervisor stack so it
- *  uses it's own stack area reserved in the int array remcomStack.  
- * 
- *************
- *
- *    The following gdb commands are supported:
- * 
- * command          function                               Return value
- * 
- *    g             return the value of the CPU registers  hex data or ENN
- *    G             set the value of the CPU registers     OK or ENN
- * 
- *    mAA..AA,LLLL  Read LLLL bytes at address AA..AA      hex data or ENN
- *    MAA..AA,LLLL: Write LLLL bytes at address AA.AA      OK or ENN
- * 
- *    c             Resume at current address              SNN   ( signal NN)
- *    cAA..AA       Continue at address AA..AA             SNN
- * 
- *    s             Step one instruction                   SNN
- *    sAA..AA       Step one instruction from AA..AA       SNN
- * 
- *    k             kill
- *
- *    ?             What was the last sigval ?             SNN   (signal NN)
- * 
- * All commands and responses are sent with a packet which includes a 
- * checksum.  A packet consists of 
- * 
- * $<packet info>#<checksum>.
- * 
- * where
- * <packet info> :: <characters representing the command or response>
- * <checksum>    :: < two hex digits computed as modulo 256 sum of <packetinfo>>
- * 
- * When a packet is received, it is first acknowledged with either '+' or '-'.
- * '+' indicates a successful transfer.  '-' indicates a failed transfer.
- * 
- * Example:
- * 
- * Host:                  Reply:
- * $m0,10#2a               +$00010203040506070809101112131415#42
- * 
- ****************************************************************************/
-
-#include <stdio.h>
-#include <string.h>
-#include <setjmp.h>
-
-/************************************************************************
- *
- * external low-level support routines 
- */
-typedef void (*ExceptionHook)(int);   /* pointer to function with int parm */
-typedef void (*Function)();           /* pointer to a function */
-
-extern putDebugChar();   /* write a single character      */
-extern getDebugChar();   /* read and return a single char */
-
-extern Function exceptionHandler();  /* assign an exception handler */
-extern ExceptionHook exceptionHook;  /* hook variable for errors/exceptions */
-
-/************************/
-/* FORWARD DECLARATIONS */
-/************************/
-static void
-initializeRemcomErrorFrame ();
-
-/************************************************************************/
-/* BUFMAX defines the maximum number of characters in inbound/outbound buffers*/
-/* at least NUMREGBYTES*2 are needed for register packets */
-#define BUFMAX 400
-
-static char initialized;  /* boolean flag. != 0 means we've been initialized */
-
-int     remote_debug;
-/*  debug >  0 prints ill-formed commands in valid packets & checksum errors */ 
-
-static const char hexchars[]="0123456789abcdef";
-
-/* there are 180 bytes of registers on a 68020 w/68881      */
-/* many of the fpa registers are 12 byte (96 bit) registers */
-#define NUMREGBYTES 180
-enum regnames {D0,D1,D2,D3,D4,D5,D6,D7, 
-               A0,A1,A2,A3,A4,A5,A6,A7, 
-               PS,PC,
-               FP0,FP1,FP2,FP3,FP4,FP5,FP6,FP7,
-               FPCONTROL,FPSTATUS,FPIADDR
-              };
-
-
-/* We keep a whole frame cache here.  "Why?", I hear you cry, "doesn't
-   GDB handle that sort of thing?"  Well, yes, I believe the only
-   reason for this cache is to save and restore floating point state
-   (fsave/frestore).  A cleaner way to do this would be to make the
- fsave data part of the registers which GDB deals with like any
-   other registers.  This should not be a performance problem if the
-   ability to read individual registers is added to the protocol.  */
-
-typedef struct FrameStruct
-{
-    struct FrameStruct  *previous;
-    int       exceptionPC;      /* pc value when this frame created */
-    int       exceptionVector;  /* cpu vector causing exception     */
-    short     frameSize;        /* size of cpu frame in words       */
-    short     sr;               /* for 68000, this not always sr    */
-    int       pc;
-    short     format;
-    int       fsaveHeader;
-    int       morejunk[0];        /* exception frame, fp save... */
-} Frame;
-
-#define FRAMESIZE 500
-int   gdbFrameStack[FRAMESIZE];
-static Frame *lastFrame;
-
-/*
- * these should not be static cuz they can be used outside this module
- */
-int registers[NUMREGBYTES/4];
-int superStack;
-
-#define STACKSIZE 10000
-int remcomStack[STACKSIZE/sizeof(int)];
-static int* stackPtr = &remcomStack[STACKSIZE/sizeof(int) - 1];
-
-/*
- * In many cases, the system will want to continue exception processing
- * when a continue command is given.  
- * oldExceptionHook is a function to invoke in this case.
- */
-
-static ExceptionHook oldExceptionHook;
-
-/* the size of the exception stack on the 68020 varies with the type of
- * exception.  The following table is the number of WORDS used
- * for each exception format.
- */
-const short exceptionSize[] = { 4,4,6,4,4,4,4,4,29,10,16,46,12,4,4,4 };
-
-/************* jump buffer used for setjmp/longjmp **************************/
-jmp_buf remcomEnv;
-
-/***************************  ASSEMBLY CODE MACROS *************************/
-/* 									   */
-
-#ifdef __HAVE_68881__
-/* do an fsave, then remember the address to begin a restore from */
-#define SAVE_FP_REGS()    asm(" fsave   a0@-");		\
-			  asm(" fmovemx fp0-fp7,_registers+72");        \
-			  asm(" fmoveml fpcr/fpsr/fpi,_registers+168"); 
-#define RESTORE_FP_REGS()                              \
-asm("                                                \n\
-    fmoveml  _registers+168,fpcr/fpsr/fpi            \n\
-    fmovemx  _registers+72,fp0-fp7                   \n\
-    cmpl     #-1,a0@     |  skip frestore flag set ? \n\
-    beq      skip_frestore                           \n\
-    frestore a0@+                                    \n\
-skip_frestore:                                       \n\
-");
-
-#else
-#define SAVE_FP_REGS()
-#define RESTORE_FP_REGS()
-#endif /* __HAVE_68881__ */
-
-void return_to_super();
-void return_to_user();
-
-asm("
-.text
-.globl _return_to_super
-_return_to_super:
-        movel   _registers+60,sp /* get new stack pointer */        
-        movel   _lastFrame,a0   /* get last frame info  */              
-        bra     return_to_any
-
-.globl _return_to_user
-_return_to_user:
-        movel   _registers+60,a0 /* get usp */                          
-        movel   a0,usp           /* set usp */				
-        movel   _superStack,sp  /* get original stack pointer */        
-
-return_to_any:
-        movel   _lastFrame,a0   /* get last frame info  */              
-        movel   a0@+,_lastFrame /* link in previous frame     */        
-        addql   #8,a0           /* skip over pc, vector#*/              
-        movew   a0@+,d0         /* get # of words in cpu frame */       
-        addw    d0,a0           /* point to end of data        */       
-        addw    d0,a0           /* point to end of data        */       
-        movel   a0,a1                                                   
-#                                                                       
-# copy the stack frame                                                  
-        subql   #1,d0                                                   
-copyUserLoop:                                                               
-        movew   a1@-,sp@-                                               
-        dbf     d0,copyUserLoop                                             
-");                                                                     
-        RESTORE_FP_REGS()                                              
-   asm("   moveml  _registers,d0-d7/a0-a6");			        
-   asm("   rte");  /* pop and go! */                                    
-
-#define DISABLE_INTERRUPTS()   asm("         oriw   #0x0700,sr");
-#define BREAKPOINT() asm("   trap #1");
-
-/* this function is called immediately when a level 7 interrupt occurs */
-/* if the previous interrupt level was 7 then we're already servicing  */
-/* this interrupt and an rte is in order to return to the debugger.    */
-/* For the 68000, the offset for sr is 6 due to the jsr return address */
-asm("
-.text
-.globl __debug_level7
-__debug_level7:
-	movew   d0,sp@-");
-#ifdef mc68020
-asm("	movew   sp@(2),d0");
-#else
-asm("	movew   sp@(6),d0");
-#endif
-asm("	andiw   #0x700,d0
-	cmpiw   #0x700,d0
-	beq     _already7
-        movew   sp@+,d0	
-        bra     __catchException
-_already7:
-	movew   sp@+,d0");
-#ifndef mc68020
-asm("	lea     sp@(4),sp");     /* pull off 68000 return address */
-#endif
-asm("	rte");
-
-extern void _catchException ();
-
-#ifdef mc68020
-/* This function is called when a 68020 exception occurs.  It saves
- * all the cpu and fpcp regs in the _registers array, creates a frame on a
- * linked list of frames which has the cpu and fpcp stack frames needed
- * to properly restore the context of these processors, and invokes
- * an exception handler (remcom_handler).
- *
- * stack on entry:                       stack on exit:
- *   N bytes of junk                     exception # MSWord
- *   Exception Format Word               exception # MSWord
- *   Program counter LSWord              
- *   Program counter MSWord             
- *   Status Register                    
- *                                       
- *                                       
- */
-asm(" 
-.text
-.globl __catchException
-__catchException:");
-DISABLE_INTERRUPTS();
-asm("
-        moveml  d0-d7/a0-a6,_registers /* save registers        */
-	movel	_lastFrame,a0	/* last frame pointer */
-");
-SAVE_FP_REGS();        
-asm("
-	lea     _registers,a5   /* get address of registers     */
-        movew   sp@,d1          /* get status register          */
-        movew   d1,a5@(66)      /* save sr		 	*/	
-	movel   sp@(2),a4       /* save pc in a4 for later use  */
-        movel   a4,a5@(68)      /* save pc in _regisers[]      	*/
-
-#
-# figure out how many bytes in the stack frame
-	movew   sp@(6),d0	/* get '020 exception format	*/
-        movew   d0,d2           /* make a copy of format word   */
-        andiw   #0xf000,d0      /* mask off format type         */
-        rolw    #5,d0           /* rotate into the low byte *2  */
-        lea     _exceptionSize,a1   
-        addw    d0,a1           /* index into the table         */
-	movew   a1@,d0          /* get number of words in frame */
-        movew   d0,d3           /* save it                      */
-        subw    d0,a0		/* adjust save pointer          */
-        subw    d0,a0		/* adjust save pointer(bytes)   */
-	movel   a0,a1           /* copy save pointer            */
-	subql   #1,d0           /* predecrement loop counter    */
-#
-# copy the frame
-saveFrameLoop:
-	movew  	sp@+,a1@+
-	dbf     d0,saveFrameLoop
-#
-# now that the stack has been clenaed,
-# save the a7 in use at time of exception
-        movel   sp,_superStack  /* save supervisor sp           */
-        andiw   #0x2000,d1      /* were we in supervisor mode ? */
-        beq     userMode       
-        movel   a7,a5@(60)      /* save a7                  */
-        bra     a7saveDone
-userMode:  
-	movel   usp,a1    	
-        movel   a1,a5@(60)      /* save user stack pointer	*/
-a7saveDone:
-
-#
-# save size of frame
-        movew   d3,a0@-
-
-#
-# compute exception number
-	andl    #0xfff,d2   	/* mask off vector offset	*/
-	lsrw    #2,d2   	/* divide by 4 to get vect num	*/
-        movel   d2,a0@-         /* save it                      */
-#
-# save pc causing exception
-        movel   a4,a0@-
-#
-# save old frame link and set the new value
-	movel	_lastFrame,a1	/* last frame pointer */
-	movel   a1,a0@-		/* save pointer to prev frame	*/
-        movel   a0,_lastFrame
-
-        movel   d2,sp@-		/* push exception num           */
-	movel   _exceptionHook,a0  /* get address of handler */
-        jbsr    a0@             /* and call it */
-        clrl    sp@             /* replace exception num parm with frame ptr */
-        jbsr     __returnFromException   /* jbsr, but never returns */
-");
-#else /* mc68000 */
-/* This function is called when an exception occurs.  It translates the
- * return address found on the stack into an exception vector # which
- * is then handled by either handle_exception or a system handler.
- * _catchException provides a front end for both.  
- *
- * stack on entry:                       stack on exit:
- *   Program counter MSWord              exception # MSWord 
- *   Program counter LSWord              exception # MSWord
- *   Status Register                     
- *   Return Address  MSWord              
- *   Return Address  LSWord             
- */
-asm("
-.text
-.globl __catchException
-__catchException:");
-DISABLE_INTERRUPTS();
-asm("
-        moveml d0-d7/a0-a6,_registers  /* save registers               */
-	movel	_lastFrame,a0	/* last frame pointer */
-");
-SAVE_FP_REGS();        
-asm("
-        lea     _registers,a5   /* get address of registers     */
-        movel   sp@+,d2         /* pop return address           */
-	addl 	#1530,d2        /* convert return addr to 	*/
-	divs 	#6,d2   	/*  exception number		*/
-	extl    d2   
-
-        moveql  #3,d3           /* assume a three word frame     */
-
-        cmpiw   #3,d2           /* bus error or address error ? */
-        bgt     normal          /* if >3 then normal error      */
-        movel   sp@+,a0@-       /* copy error info to frame buff*/
-        movel   sp@+,a0@-       /* these are never used         */
-        moveql  #7,d3           /* this is a 7 word frame       */
-     
-normal:   
-	movew   sp@+,d1         /* pop status register          */
-        movel   sp@+,a4         /* pop program counter          */
-        movew   d1,a5@(66)      /* save sr		 	*/	
-        movel   a4,a5@(68)      /* save pc in _regisers[]      	*/
-        movel   a4,a0@-         /* copy pc to frame buffer      */
-	movew   d1,a0@-         /* copy sr to frame buffer      */
-
-        movel   sp,_superStack  /* save supervisor sp          */
-
-        andiw   #0x2000,d1      /* were we in supervisor mode ? */
-        beq     userMode       
-        movel   a7,a5@(60)      /* save a7                  */
-        bra     saveDone             
-userMode:
-        movel   usp,a1    	/* save user stack pointer 	*/
-        movel   a1,a5@(60)      /* save user stack pointer	*/
-saveDone:
-
-        movew   d3,a0@-         /* push frame size in words     */
-        movel   d2,a0@-         /* push vector number           */
-        movel   a4,a0@-         /* push exception pc            */
-
-#
-# save old frame link and set the new value
-	movel	_lastFrame,a1	/* last frame pointer */
-	movel   a1,a0@-		/* save pointer to prev frame	*/
-        movel   a0,_lastFrame
-
-        movel   d2,sp@-		/* push exception num           */
-	movel   _exceptionHook,a0  /* get address of handler */
-        jbsr    a0@             /* and call it */
-        clrl    sp@             /* replace exception num parm with frame ptr */
-        jbsr     __returnFromException   /* jbsr, but never returns */
-");
-#endif
-
-
-/*
- * remcomHandler is a front end for handle_exception.  It moves the
- * stack pointer into an area reserved for debugger use in case the
- * breakpoint happened in supervisor mode.
- */
-asm("_remcomHandler:");
-asm("           addl    #4,sp");        /* pop off return address     */
-asm("           movel   sp@+,d0");      /* get the exception number   */
-asm("		movel   _stackPtr,sp"); /* move to remcom stack area  */
-asm("		movel   d0,sp@-");	/* push exception onto stack  */
-asm("		jbsr    _handle_exception");    /* this never returns */
-asm("           rts");                  /* return */
-
-void _returnFromException( Frame *frame )
-{
-    /* if no passed in frame, use the last one */
-    if (! frame)
-    {
-        frame = lastFrame;
-	frame->frameSize = 4;
-        frame->format = 0;
-        frame->fsaveHeader = -1; /* restore regs, but we dont have fsave info*/
-    }
-
-#ifndef mc68020
-    /* a 68000 cannot use the internal info pushed onto a bus error
-     * or address error frame when doing an RTE so don't put this info
-     * onto the stack or the stack will creep every time this happens.
-     */
-    frame->frameSize=3;
-#endif
-
-    /* throw away any frames in the list after this frame */
-    lastFrame = frame;
-
-    frame->sr = registers[(int) PS];
-    frame->pc = registers[(int) PC];
-
-    if (registers[(int) PS] & 0x2000)
-    { 
-        /* return to supervisor mode... */
-        return_to_super();
-    }
-    else
-    { /* return to user mode */
-        return_to_user();
-    }
-}
-
-int hex(ch)
-char ch;
-{
-  if ((ch >= 'a') && (ch <= 'f')) return (ch-'a'+10);
-  if ((ch >= '0') && (ch <= '9')) return (ch-'0');
-  if ((ch >= 'A') && (ch <= 'F')) return (ch-'A'+10);
-  return (-1);
-}
-
-
-/* scan for the sequence $<data>#<checksum>     */
-void getpacket(buffer)
-char * buffer;
-{
-  unsigned char checksum;
-  unsigned char xmitcsum;
-  int  i;
-  int  count;
-  char ch;
-  
-  do {
-    /* wait around for the start character, ignore all other characters */
-    while ((ch = getDebugChar()) != '$'); 
-    checksum = 0;
-    xmitcsum = -1;
-    
-    count = 0;
-    
-    /* now, read until a # or end of buffer is found */
-    while (count < BUFMAX) {
-      ch = getDebugChar();
-      if (ch == '#') break;
-      checksum = checksum + ch;
-      buffer[count] = ch;
-      count = count + 1;
-      }
-    buffer[count] = 0;
-
-    if (ch == '#') {
-      xmitcsum = hex(getDebugChar()) << 4;
-      xmitcsum += hex(getDebugChar());
-      if ((remote_debug ) && (checksum != xmitcsum)) {
-        fprintf(stderr,"bad checksum.  My count = 0x%x, sent=0x%x. buf=%s\n",
-						     checksum,xmitcsum,buffer);
-      }
-      
-      if (checksum != xmitcsum) putDebugChar('-');  /* failed checksum */ 
-      else {
-	 putDebugChar('+');  /* successful transfer */
-	 /* if a sequence char is present, reply the sequence ID */
-	 if (buffer[2] == ':') {
-	    putDebugChar( buffer[0] );
-	    putDebugChar( buffer[1] );
-	    /* remove sequence chars from buffer */
-	    count = strlen(buffer);
-	    for (i=3; i <= count; i++) buffer[i-3] = buffer[i];
-	 } 
-      } 
-    } 
-  } while (checksum != xmitcsum);
-  
-}
-
-/* send the packet in buffer.  The host get's one chance to read it.  
-   This routine does not wait for a positive acknowledge.  */
-
-
-void putpacket(buffer)
-char * buffer;
-{
-  unsigned char checksum;
-  int  count;
-  char ch;
-  
-  /*  $<packet info>#<checksum>. */
-  do {
-  putDebugChar('$');
-  checksum = 0;
-  count    = 0;
-  
-  while (ch=buffer[count]) {
-    if (! putDebugChar(ch)) return;
-    checksum += ch;
-    count += 1;
-  }
-  
-  putDebugChar('#');
-  putDebugChar(hexchars[checksum >> 4]);
-  putDebugChar(hexchars[checksum % 16]);
-
-  } while (1 == 0);  /* (getDebugChar() != '+'); */
-  
-}
-
-char  remcomInBuffer[BUFMAX];
-char  remcomOutBuffer[BUFMAX];
-static short error;
-
-
-void debug_error(format, parm)
-char * format;
-char * parm;
-{
-  if (remote_debug) fprintf(stderr,format,parm);
-}
-
-/* convert the memory pointed to by mem into hex, placing result in buf */
-/* return a pointer to the last char put in buf (null) */
-char* mem2hex(mem, buf, count)
-char* mem;
-char* buf;
-int   count;
-{
-      int i;
-      unsigned char ch;
-      for (i=0;i<count;i++) {
-          ch = *mem++;
-          *buf++ = hexchars[ch >> 4];
-          *buf++ = hexchars[ch % 16];
-      }
-      *buf = 0; 
-      return(buf);
-}
-
-/* convert the hex array pointed to by buf into binary to be placed in mem */
-/* return a pointer to the character AFTER the last byte written */
-char* hex2mem(buf, mem, count)
-char* buf;
-char* mem;
-int   count;
-{
-      int i;
-      unsigned char ch;
-      for (i=0;i<count;i++) {
-          ch = hex(*buf++) << 4;
-          ch = ch + hex(*buf++);
-          *mem++ = ch;
-      }
-      return(mem);
-}
-
-/* a bus error has occurred, perform a longjmp
-   to return execution and allow handling of the error */
-
-void handle_buserror()
-{
-  longjmp(remcomEnv,1);
-}
-
-/* this function takes the 68000 exception number and attempts to 
-   translate this number into a unix compatible signal value */
-int computeSignal( exceptionVector )
-int exceptionVector;
-{
-  int sigval;
-  switch (exceptionVector) {
-    case 2 : sigval = 10; break; /* bus error           */
-    case 3 : sigval = 10; break; /* address error       */
-    case 4 : sigval = 4;  break; /* illegal instruction */
-    case 5 : sigval = 8;  break; /* zero divide         */
-    case 6 : sigval = 16; break; /* chk instruction     */
-    case 7 : sigval = 16; break; /* trapv instruction   */
-    case 8 : sigval = 11; break; /* privilege violation */
-    case 9 : sigval = 5;  break; /* trace trap          */
-    case 10: sigval = 4;  break; /* line 1010 emulator  */
-    case 11: sigval = 4;  break; /* line 1111 emulator  */
-    case 13: sigval = 8;  break; /* floating point err  */
-    case 31: sigval = 2;  break; /* interrupt           */
-    case 33: sigval = 5;  break; /* breakpoint          */
-
-      /* This is a trap #8 instruction.  Apparently it is someone's software
-	 convention for some sort of SIGFPE condition.  Whose?  How many
-	 people are being screwed by having this code the way it is?
-	 Is there a clean solution?  */
-    case 40: sigval = 8;  break; /* floating point err  */
-
-    case 48: sigval = 8;  break; /* floating point err  */
-    case 49: sigval = 8;  break; /* floating point err  */
-    case 50: sigval = 8;  break; /* zero divide         */
-    case 51: sigval = 8;  break; /* underflow           */
-    case 52: sigval = 8;  break; /* operand error       */
-    case 53: sigval = 8;  break; /* overflow            */
-    case 54: sigval = 8;  break; /* NAN                 */
-    default: 
-      sigval = 7;         /* "software generated"*/
-  }
-  return (sigval);
-}
-
-/**********************************************/
-/* WHILE WE FIND NICE HEX CHARS, BUILD AN INT */
-/* RETURN NUMBER OF CHARS PROCESSED           */
-/**********************************************/
-int hexToInt(char **ptr, int *intValue)
-{
-    int numChars = 0;
-    int hexValue;
-    
-    *intValue = 0;
-
-    while (**ptr)
-    {
-        hexValue = hex(**ptr);
-        if (hexValue >=0)
-        {
-            *intValue = (*intValue <<4) | hexValue;
-            numChars ++;
-        }
-        else
-            break;
-        
-        (*ptr)++;
-    }
-
-    return (numChars);
-}
-
-/*
- * This function does all command procesing for interfacing to gdb.
- */
-void handle_exception(int exceptionVector)
-{
-  int    sigval;
-  int    addr, length;
-  char * ptr;
-  int    newPC;
-  Frame  *frame;
-  
-  if (remote_debug) printf("vector=%d, sr=0x%x, pc=0x%x\n", 
-			    exceptionVector,
-			    registers[ PS ], 
-			    registers[ PC ]);
-
-  /* reply to host that an exception has occurred */
-  sigval = computeSignal( exceptionVector );
-  remcomOutBuffer[0] = 'S';
-  remcomOutBuffer[1] =  hexchars[sigval >> 4];
-  remcomOutBuffer[2] =  hexchars[sigval % 16];
-  remcomOutBuffer[3] = 0;
-
-  putpacket(remcomOutBuffer); 
-
-  while (1==1) { 
-    error = 0;
-    remcomOutBuffer[0] = 0;
-    getpacket(remcomInBuffer);
-    switch (remcomInBuffer[0]) {
-      case '?' :   remcomOutBuffer[0] = 'S';
-                   remcomOutBuffer[1] =  hexchars[sigval >> 4];
-                   remcomOutBuffer[2] =  hexchars[sigval % 16];
-                   remcomOutBuffer[3] = 0;
-                 break; 
-      case 'd' : remote_debug = !(remote_debug);  /* toggle debug flag */
-                 break; 
-      case 'g' : /* return the value of the CPU registers */
-                mem2hex((char*) registers, remcomOutBuffer, NUMREGBYTES);
-                break;
-      case 'G' : /* set the value of the CPU registers - return OK */
-                hex2mem(&remcomInBuffer[1], (char*) registers, NUMREGBYTES);
-                strcpy(remcomOutBuffer,"OK");
-                break;
-      
-      /* mAA..AA,LLLL  Read LLLL bytes at address AA..AA */
-      case 'm' : 
-	        if (setjmp(remcomEnv) == 0)
-                {
-                    exceptionHandler(2,handle_buserror); 
-
-		    /* TRY TO READ %x,%x.  IF SUCCEED, SET PTR = 0 */
-                    ptr = &remcomInBuffer[1];
-                    if (hexToInt(&ptr,&addr))
-                        if (*(ptr++) == ',')
-                            if (hexToInt(&ptr,&length)) 
-                            {
-                                ptr = 0;
-                                mem2hex((char*) addr, remcomOutBuffer, length);
-                            }
-
-                    if (ptr)
-                    {
-		      strcpy(remcomOutBuffer,"E01");
-		      debug_error("malformed read memory command: %s",remcomInBuffer);
-                  }     
-                } 
-		else {
-		  exceptionHandler(2,_catchException);   
-		  strcpy(remcomOutBuffer,"E03");
-		  debug_error("bus error");
-		  }     
-                
-		/* restore handler for bus error */
-		exceptionHandler(2,_catchException);   
-		break;
-      
-      /* MAA..AA,LLLL: Write LLLL bytes at address AA.AA return OK */
-      case 'M' : 
-	        if (setjmp(remcomEnv) == 0) {
-		    exceptionHandler(2,handle_buserror); 
-                    
-		    /* TRY TO READ '%x,%x:'.  IF SUCCEED, SET PTR = 0 */
-                    ptr = &remcomInBuffer[1];
-                    if (hexToInt(&ptr,&addr))
-                        if (*(ptr++) == ',')
-                            if (hexToInt(&ptr,&length))
-                                if (*(ptr++) == ':')
-                                {
-                                    hex2mem(ptr, (char*) addr, length);
-                                    ptr = 0;
-                                    strcpy(remcomOutBuffer,"OK");
-                                }
-                    if (ptr)
-                    {
-		      strcpy(remcomOutBuffer,"E02");
-		      debug_error("malformed write memory command: %s",remcomInBuffer);
-		      }     
-                } 
-		else {
-		  exceptionHandler(2,_catchException);   
-		  strcpy(remcomOutBuffer,"E03");
-		  debug_error("bus error");
-		  }     
-
-                /* restore handler for bus error */
-                exceptionHandler(2,_catchException);   
-                break;
-     
-     /* cAA..AA    Continue at address AA..AA(optional) */
-     /* sAA..AA   Step one instruction from AA..AA(optional) */
-     case 'c' : 
-     case 's' : 
-          /* try to read optional parameter, pc unchanged if no parm */
-         ptr = &remcomInBuffer[1];
-         if (hexToInt(&ptr,&addr))
-             registers[ PC ] = addr;
-             
-          newPC = registers[ PC];
-          
-          /* clear the trace bit */
-          registers[ PS ] &= 0x7fff;
-          
-          /* set the trace bit if we're stepping */
-          if (remcomInBuffer[0] == 's') registers[ PS ] |= 0x8000;
-          
-          /*
-           * look for newPC in the linked list of exception frames.
-           * if it is found, use the old frame it.  otherwise,
-           * fake up a dummy frame in returnFromException().
-           */
-          if (remote_debug) printf("new pc = 0x%x\n",newPC);
-          frame = lastFrame;
-          while (frame)
-          {
-              if (remote_debug)
-                  printf("frame at 0x%x has pc=0x%x, except#=%d\n",
-                         frame,frame->exceptionPC,
-                         frame->exceptionVector);
-              if (frame->exceptionPC == newPC) break;  /* bingo! a match */
-              /*
-               * for a breakpoint instruction, the saved pc may
-               * be off by two due to re-executing the instruction
-               * replaced by the trap instruction.  Check for this.
-               */
-              if ((frame->exceptionVector == 33) &&
-                  (frame->exceptionPC == (newPC+2))) break;
-              if (frame == frame->previous)
-	      {
-	          frame = 0; /* no match found */ 
-	          break; 
-	      }
-	      frame = frame->previous;
-          }
-          
-          /*
-           * If we found a match for the PC AND we are not returning
-           * as a result of a breakpoint (33),
-           * trace exception (9), nmi (31), jmp to
-           * the old exception handler as if this code never ran.
-           */
-          if (frame) 
-          {
-              if ((frame->exceptionVector != 9)  && 
-                  (frame->exceptionVector != 31) && 
-                  (frame->exceptionVector != 33))
-              { 
-                  /*
-                   * invoke the previous handler.
-                   */
-                  if (oldExceptionHook)
-                      (*oldExceptionHook) (frame->exceptionVector);
-                  newPC = registers[ PC ];    /* pc may have changed  */
-                  if (newPC != frame->exceptionPC)
-                  {
-                      if (remote_debug)
-                          printf("frame at 0x%x has pc=0x%x, except#=%d\n",
-                                 frame,frame->exceptionPC,
-                                 frame->exceptionVector);
-                      /* re-use the last frame, we're skipping it (longjump?)*/
-		      frame = (Frame *) 0;
-	              _returnFromException( frame );  /* this is a jump */
-                  }
-              }
-          }         
-
-    	  /* if we couldn't find a frame, create one */
-          if (frame == 0)
-	  {
-    	      frame = lastFrame -1 ;
-	      
-	      /* by using a bunch of print commands with breakpoints,
-    	         it's possible for the frame stack to creep down.  If it creeps
-		 too far, give up and reset it to the top.  Normal use should
-    	         not see this happen.
-    	      */
-	      if ((unsigned int) (frame-2) < (unsigned int) &gdbFrameStack)
-    	      {
-    	         initializeRemcomErrorFrame();
-    	         frame = lastFrame; 
-	      }
-    	      frame->previous = lastFrame;
-              lastFrame = frame;
-              frame = 0;  /* null so _return... will properly initialize it */ 
-	  }    
-	  
-	  _returnFromException( frame ); /* this is a jump */
-
-          break;
-          
-      /* kill the program */
-      case 'k' :  /* do nothing */
-                break;
-      } /* switch */ 
-    
-    /* reply to the request */
-    putpacket(remcomOutBuffer); 
-    }
-}
-
-
-void
-initializeRemcomErrorFrame()
-{
-    lastFrame = ((Frame *) &gdbFrameStack[FRAMESIZE-1]) - 1;
-    lastFrame->previous = lastFrame;
-}
-
-/* this function is used to set up exception handlers for tracing and 
-   breakpoints */
-void set_debug_traps()
-{
-  extern void _debug_level7();
-  extern void remcomHandler();
-  int exception;
-
-  initializeRemcomErrorFrame();
-  stackPtr  = &remcomStack[STACKSIZE/sizeof(int) - 1];
-
-  for (exception = 2; exception <= 23; exception++)
-      exceptionHandler(exception,_catchException);   
-
-  /* level 7 interrupt              */
-  exceptionHandler(31,_debug_level7);    
-  
-  /* breakpoint exception (trap #1) */
-  exceptionHandler(33,_catchException);
-  
-  /* This is a trap #8 instruction.  Apparently it is someone's software
-     convention for some sort of SIGFPE condition.  Whose?  How many
-     people are being screwed by having this code the way it is?
-     Is there a clean solution?  */
-  exceptionHandler(40,_catchException);
-  
-  /* 48 to 54 are floating point coprocessor errors */
-  for (exception = 48; exception <= 54; exception++)
-      exceptionHandler(exception,_catchException);   
-
-  if (oldExceptionHook != remcomHandler)
-  {
-      oldExceptionHook = exceptionHook;
-      exceptionHook    = remcomHandler;
-  }
-  
-  initialized = 1;
-
-}
-
-/* This function will generate a breakpoint exception.  It is used at the
-   beginning of a program to sync up with a debugger and can be used
-   otherwise as a quick means to stop program execution and "break" into
-   the debugger. */
-   
-void breakpoint()
-{
-  if (initialized) BREAKPOINT();
-}
-