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author | K. Richard Pixley <rich@cygnus> | 1992-12-08 04:59:31 +0000 |
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committer | K. Richard Pixley <rich@cygnus> | 1992-12-08 04:59:31 +0000 |
commit | 43bbd567f2d928b2628e508ee9c75a3920e26b4d (patch) | |
tree | 21f1ab246e1a3f963e73c3662bc1d44f591349a1 /gdb/remote-sa.m68k.shar | |
parent | a362ee23634a2f9ce9642eab09592e8ff6ae509b (diff) | |
download | gdb-43bbd567f2d928b2628e508ee9c75a3920e26b4d.zip gdb-43bbd567f2d928b2628e508ee9c75a3920e26b4d.tar.gz gdb-43bbd567f2d928b2628e508ee9c75a3920e26b4d.tar.bz2 |
recording file death
Diffstat (limited to 'gdb/remote-sa.m68k.shar')
-rwxr-xr-x | gdb/remote-sa.m68k.shar | 893 |
1 files changed, 0 insertions, 893 deletions
diff --git a/gdb/remote-sa.m68k.shar b/gdb/remote-sa.m68k.shar deleted file mode 100755 index aeb76e5..0000000 --- a/gdb/remote-sa.m68k.shar +++ /dev/null @@ -1,893 +0,0 @@ -# This is a shell archive. Remove anything before this line, -# then unpack it by saving it in a file and typing "sh file". -# -# Wrapped by Glenn Engel <glenne@labgre> on Mon Jun 12 15:19:20 1989 -# -# This archive contains: -# remcom.c -# - -LANG=""; export LANG -PATH=/bin:/usr/bin:$PATH; export PATH - -echo x - remcom.c -cat >remcom.c <<'@EOF' - -/**************************************************************************** - - 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. - -****************************************************************************/ - -/**************************************************************************** - * $Header$ - * - * $Module name: remcom.c $ - * $Revision$ - * $Date$ - * $Contributor: Lake Stevens Instrument Division$ - * - * $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. - * - * 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 68k 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 */ - - -/************************************************************************/ -/* 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 = 0; -/* debug > 0 prints ill-formed commands in valid packets & checksum errors */ - -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 - }; - -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 -static Frame *lastFrame; -static int frameStack[FRAMESIZE]; - -/* - * these should not be static cuz they can be used outside this module - */ -int registers[NUMREGBYTES/4]; -int superStack; - -static int remcomStack[400]; -static int* stackPtr = &remcomStack[399]; - -/* - * 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. - */ -static short exceptionSize[] = { 4,4,6,4,4,4,4,4,29,10,16,46,4,4,4,4 }; - -/************* jump buffer used for setjmp/longjmp **************************/ -jmp_buf env; - -/*************************** 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(" fmoveml _registers+168,fpcr/fpsr/fpi"); \ - asm(" fmovemx _registers+72,fp0-fp7"); \ - asm(" frestore a0@+"); -#else -#define SAVE_FP_REGS() -#define RESTORE_FP_REGS() -#endif /* __HAVE_68881__ */ - -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 */ - jmp __returnFromException /* now, return */ -"); -#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 */ - jmp __returnFromException /* now, return */ -"); -#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 existing frame, dummy one up */ - if (! frame) - { - frame = lastFrame -1; - frame->frameSize = 4; - frame->format = 0; - frame->fsaveHeader = 0; - frame->previous = lastFrame; - } - -#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'); - return (0); -} - - -/* 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; - 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() != '+'); */ - -} - -static char inbuffer[BUFMAX]; -static char outbuffer[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(env,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 31: sigval = 2; break; /* interrupt */ - case 33: sigval = 5; break; /* breakpoint */ - 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); -} - -/* - * 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 ); - sprintf(outbuffer,"S%02x",sigval); - putpacket(outbuffer); - - while (1==1) { - error = 0; - outbuffer[0] = 0; - getpacket(inbuffer); - switch (inbuffer[0]) { - case '?' : sprintf(outbuffer,"S%02x",sigval); - break; - case 'd' : remote_debug = !(remote_debug); /* toggle debug flag */ - break; - case 'g' : /* return the value of the CPU registers */ - mem2hex((char*) registers, outbuffer, NUMREGBYTES); - break; - case 'G' : /* set the value of the CPU registers - return OK */ - hex2mem(&inbuffer[1], (char*) registers, NUMREGBYTES); - strcpy(outbuffer,"OK"); - break; - - /* mAA..AA,LLLL Read LLLL bytes at address AA..AA */ - case 'm' : - if (setjmp(env) == 0) { - exceptionHandler(2,handle_buserror); - - if (2 == sscanf(&inbuffer[1],"%x,%x",&addr,&length)) { - mem2hex((char*) addr, outbuffer, length); - } - else { - strcpy(outbuffer,"E01"); - debug_error("malformed read memory command: %s",inbuffer); - } - } - else { - exceptionHandler(2,_catchException); - strcpy(outbuffer,"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(env) == 0) { - exceptionHandler(2,handle_buserror); - - if (2 == sscanf(&inbuffer[1],"%x,%x:",&addr,&length)) { - ptr = strchr(inbuffer,':'); - ptr += 1; /* point 1 past the colon */ - hex2mem(ptr, (char*) addr, length); - strcpy(outbuffer,"OK"); - } - else { - strcpy(outbuffer,"E02"); - debug_error("malformed write memory command: %s",inbuffer); - } - } - else { - exceptionHandler(2,_catchException); - strcpy(outbuffer,"E03"); - debug_error("bus error"); - } - 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, addr unchanged if no parm */ - if (1 == sscanf(&inbuffer[1],"%x",®isters[ PC ])); - newPC = registers[ PC]; - - /* clear the trace bit */ - registers[ PS ] &= 0x7fff; - - /* set the trace bit if we're stepping */ - if (inbuffer[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; - 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); - /* dispose of this frame, we're skipping it (longjump?)*/ - lastFrame = frame->previous; - frame = (Frame *) 0; - } - } - } - - _returnFromException( frame ); - - break; - - /* kill the program */ - case 'k' : /* do nothing */ - break; - } /* switch */ - - /* reply to the request */ - putpacket(outbuffer); - } -} - - -/* 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; - - for (exception = 2; exception <= 23; exception++) - exceptionHandler(exception,_catchException); - - /* level 7 interrupt */ - exceptionHandler(31,_debug_level7); - - /* breakpoint exception (trap #1) */ - exceptionHandler(33,_catchException); - - /* floating point error (trap #8) */ - 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; - - lastFrame = (Frame *) &frameStack[FRAMESIZE-1]; - lastFrame->previous = (Frame *) 0; -} - -/* 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(); -} - -@EOF - -chmod 444 remcom.c - -exit 0 - |