[unix-history] / sys / ddb / db_run.c

/* 
 * Mach Operating System
 * Copyright (c) 1991,1990 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS 
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie the
 * rights to redistribute these changes.
 *
 *	$Id: db_run.c,v 1.2 1993/10/16 16:47:24 rgrimes Exp $
 */

/*
 * 	Author: David B. Golub, Carnegie Mellon University
 *	Date:	7/90
 */

/*
 * Commands to run process.
 */
#include "param.h"
#include "systm.h"
#include "proc.h"
#include "ddb/ddb.h"

#include <ddb/db_lex.h>
#include <ddb/db_break.h>
#include <ddb/db_access.h>

int	db_run_mode;
#define	STEP_NONE	0
#define	STEP_ONCE	1
#define	STEP_RETURN	2
#define	STEP_CALLT	3
#define	STEP_CONTINUE	4
#define STEP_INVISIBLE	5
#define	STEP_COUNT	6

boolean_t	db_sstep_print;
int		db_loop_count;
int		db_call_depth;

int		db_inst_count;
int		db_load_count;
int		db_store_count;

#ifndef db_set_single_step
void		db_set_single_step(/* db_regs_t *regs */);	/* forward */
#endif
#ifndef db_clear_single_step
void		db_clear_single_step(/* db_regs_t *regs */);
#endif

boolean_t
db_stop_at_pc(is_breakpoint)
	boolean_t	*is_breakpoint;
{
	register db_addr_t	pc;
	register db_breakpoint_t bkpt;

	db_clear_single_step(DDB_REGS);
	db_clear_breakpoints();
	db_clear_watchpoints();
	pc = PC_REGS(DDB_REGS);

#ifdef	FIXUP_PC_AFTER_BREAK
	if (*is_breakpoint) {
	    /*
	     * Breakpoint trap.  Fix up the PC if the
	     * machine requires it.
	     */
	    FIXUP_PC_AFTER_BREAK
	    pc = PC_REGS(DDB_REGS);
	}
#endif

	/*
	 * Now check for a breakpoint at this address.
	 */
	bkpt = db_find_breakpoint_here(pc);
	if (bkpt) {
	    if (--bkpt->count == 0) {
		bkpt->count = bkpt->init_count;
		*is_breakpoint = TRUE;
		return (TRUE);	/* stop here */
	    }
	} else if (*is_breakpoint) {
		ddb_regs.tf_eip += 1;
	}
		
	*is_breakpoint = FALSE;

	if (db_run_mode == STEP_INVISIBLE) {
	    db_run_mode = STEP_CONTINUE;
	    return (FALSE);	/* continue */
	}
	if (db_run_mode == STEP_COUNT) {
	    return (FALSE); /* continue */
	}
	if (db_run_mode == STEP_ONCE) {
	    if (--db_loop_count > 0) {
		if (db_sstep_print) {
		    db_printf("\t\t");
		    db_print_loc_and_inst(pc);
		    db_printf("\n");
		}
		return (FALSE);	/* continue */
	    }
	}
	if (db_run_mode == STEP_RETURN) {
	    db_expr_t ins = db_get_value(pc, sizeof(int), FALSE);

	    /* continue until matching return */

	    if (!inst_trap_return(ins) &&
		(!inst_return(ins) || --db_call_depth != 0)) {
		if (db_sstep_print) {
		    if (inst_call(ins) || inst_return(ins)) {
			register int i;

			db_printf("[after %6d]     ", db_inst_count);
			for (i = db_call_depth; --i > 0; )
			    db_printf("  ");
			db_print_loc_and_inst(pc);
			db_printf("\n");
		    }
		}
		if (inst_call(ins))
		    db_call_depth++;
		return (FALSE);	/* continue */
	    }
	}
	if (db_run_mode == STEP_CALLT) {
	    db_expr_t ins = db_get_value(pc, sizeof(int), FALSE);

	    /* continue until call or return */

	    if (!inst_call(ins) &&
		!inst_return(ins) &&
		!inst_trap_return(ins)) {
		return (FALSE);	/* continue */
	    }
	}
	db_run_mode = STEP_NONE;
	return (TRUE);
}

void
db_restart_at_pc(watchpt)
	boolean_t watchpt;
{
	register db_addr_t	pc = PC_REGS(DDB_REGS);

	if ((db_run_mode == STEP_COUNT) ||
	    (db_run_mode == STEP_RETURN) ||
	    (db_run_mode == STEP_CALLT)) {
	    db_expr_t		ins;

	    /*
	     * We are about to execute this instruction,
	     * so count it now.
	     */

	    ins = db_get_value(pc, sizeof(int), FALSE);
	    db_inst_count++;
	    db_load_count += inst_load(ins);
	    db_store_count += inst_store(ins);
#ifdef	SOFTWARE_SSTEP
	    /* XXX works on mips, but... */
	    if (inst_branch(ins) || inst_call(ins)) {
		ins = db_get_value(next_instr_address(pc,1),
				   sizeof(int), FALSE);
		db_inst_count++;
		db_load_count += inst_load(ins);
		db_store_count += inst_store(ins);
	    }
#endif	SOFTWARE_SSTEP
	}

	if (db_run_mode == STEP_CONTINUE) {
	    if (watchpt || db_find_breakpoint_here(pc)) {
		/*
		 * Step over breakpoint/watchpoint.
		 */
		db_run_mode = STEP_INVISIBLE;
		db_set_single_step(DDB_REGS);
	    } else {
		db_set_breakpoints();
		db_set_watchpoints();
	    }
	} else {
	    db_set_single_step(DDB_REGS);
	}
}

void
db_single_step(regs)
	db_regs_t *regs;
{
	if (db_run_mode == STEP_CONTINUE) {
	    db_run_mode = STEP_INVISIBLE;
	    db_set_single_step(regs);
	}
}

#ifdef	SOFTWARE_SSTEP
/*
 *	Software implementation of single-stepping.
 *	If your machine does not have a trace mode
 *	similar to the vax or sun ones you can use
 *	this implementation, done for the mips.
 *	Just define the above conditional and provide
 *	the functions/macros defined below.
 *
 * extern boolean_t
 *	inst_branch(),		returns true if the instruction might branch
 * extern unsigned
 *	branch_taken(),		return the address the instruction might
 *				branch to
 *	db_getreg_val();	return the value of a user register,
 *				as indicated in the hardware instruction
 *				encoding, e.g. 8 for r8
 *			
 * next_instr_address(pc,bd)	returns the address of the first
 *				instruction following the one at "pc",
 *				which is either in the taken path of
 *				the branch (bd==1) or not.  This is
 *				for machines (mips) with branch delays.
 *
 *	A single-step may involve at most 2 breakpoints -
 *	one for branch-not-taken and one for branch taken.
 *	If one of these addresses does not already have a breakpoint,
 *	we allocate a breakpoint and save it here.
 *	These breakpoints are deleted on return.
 */			
db_breakpoint_t	db_not_taken_bkpt = 0;
db_breakpoint_t	db_taken_bkpt = 0;

void
db_set_single_step(regs)
	register db_regs_t *regs;
{
	db_addr_t pc = PC_REGS(regs);
	register unsigned	 inst, brpc;

	/*
	 *	User was stopped at pc, e.g. the instruction
	 *	at pc was not executed.
	 */
	inst = db_get_value(pc, sizeof(int), FALSE);
	if (inst_branch(inst) || inst_call(inst)) {
	    extern unsigned getreg_val();

	    brpc = branch_taken(inst, pc, getreg_val, regs);
	    if (brpc != pc) {	/* self-branches are hopeless */
		db_taken_bkpt = db_set_temp_breakpoint(brpc);
	    }
	    pc = next_instr_address(pc,1);
	}
	pc = next_instr_address(pc,0);
	db_not_taken_bkpt = db_set_temp_breakpoint(pc);
}

void
db_clear_single_step(regs)
	db_regs_t *regs;
{
	register db_breakpoint_t	bkpt;

	if (db_taken_bkpt != 0) {
	    db_delete_temp_breakpoint(db_taken_bkpt);
	    db_taken_bkpt = 0;
	}
	if (db_not_taken_bkpt != 0) {
	    db_delete_temp_breakpoint(db_not_taken_bkpt);
	    db_not_taken_bkpt = 0;
	}
}

#endif	SOFTWARE_SSTEP

extern int	db_cmd_loop_done;

/* single-step */
/*ARGSUSED*/
void
db_single_step_cmd(addr, have_addr, count, modif)
	db_expr_t	addr;
	int		have_addr;
	db_expr_t	count;
	char *		modif;
{
	boolean_t	print = FALSE;

	if (count == -1)
	    count = 1;

	if (modif[0] == 'p')
	    print = TRUE;

	db_run_mode = STEP_ONCE;
	db_loop_count = count;
	db_sstep_print = print;
	db_inst_count = 0;
	db_load_count = 0;
	db_store_count = 0;

	db_cmd_loop_done = 1;
}

/* trace and print until call/return */
/*ARGSUSED*/
void
db_trace_until_call_cmd(addr, have_addr, count, modif)
	db_expr_t	addr;
	int		have_addr;
	db_expr_t	count;
	char *		modif;
{
	boolean_t	print = FALSE;

	if (modif[0] == 'p')
	    print = TRUE;

	db_run_mode = STEP_CALLT;
	db_sstep_print = print;
	db_inst_count = 0;
	db_load_count = 0;
	db_store_count = 0;

	db_cmd_loop_done = 1;
}

/*ARGSUSED*/
void
db_trace_until_matching_cmd(addr, have_addr, count, modif)
	db_expr_t	addr;
	int		have_addr;
	db_expr_t	count;
	char *		modif;
{
	boolean_t	print = FALSE;

	if (modif[0] == 'p')
	    print = TRUE;

	db_run_mode = STEP_RETURN;
	db_call_depth = 1;
	db_sstep_print = print;
	db_inst_count = 0;
	db_load_count = 0;
	db_store_count = 0;

	db_cmd_loop_done = 1;
}

/* continue */
/*ARGSUSED*/
void
db_continue_cmd(addr, have_addr, count, modif)
	db_expr_t	addr;
	int		have_addr;
	db_expr_t	count;
	char *		modif;
{
	if (modif[0] == 'c')
	    db_run_mode = STEP_COUNT;
	else
	    db_run_mode = STEP_CONTINUE;
	db_inst_count = 0;
	db_load_count = 0;
	db_store_count = 0;

	db_cmd_loop_done = 1;
}
Commit	Line	Data
15637ed4 RG	1	/*
	2	* Mach Operating System
	3	* Copyright (c) 1991,1990 Carnegie Mellon University
	4	* All Rights Reserved.
	5	*
	6	* Permission to use, copy, modify and distribute this software and its
	7	* documentation is hereby granted, provided that both the copyright
	8	* notice and this permission notice appear in all copies of the
	9	* software, derivative works or modified versions, and any portions
	10	* thereof, and that both notices appear in supporting documentation.
	11	*
	12	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
	13	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
	14	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
	15	*
	16	* Carnegie Mellon requests users of this software to return to
	17	*
	18	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
	19	* School of Computer Science
	20	* Carnegie Mellon University
	21	* Pittsburgh PA 15213-3890
	22	*
	23	* any improvements or extensions that they make and grant Carnegie the
	24	* rights to redistribute these changes.
15637ed4	25	*
4c45483e	26	* $Id: db_run.c,v 1.2 1993/10/16 16:47:24 rgrimes Exp $
15637ed4	27	*/
cbeffc91	28
15637ed4 RG	29	/*
	30	* Author: David B. Golub, Carnegie Mellon University
	31	* Date: 7/90
	32	*/
	33
	34	/*
	35	* Commands to run process.
	36	*/
	37	#include "param.h"
4c45483e	38	#include "systm.h"
15637ed4	39	#include "proc.h"
4c45483e	40	#include "ddb/ddb.h"
15637ed4 RG	41
	42	#include <ddb/db_lex.h>
	43	#include <ddb/db_break.h>
	44	#include <ddb/db_access.h>
	45
	46	int db_run_mode;
	47	#define STEP_NONE 0
	48	#define STEP_ONCE 1
	49	#define STEP_RETURN 2
	50	#define STEP_CALLT 3
	51	#define STEP_CONTINUE 4
	52	#define STEP_INVISIBLE 5
	53	#define STEP_COUNT 6
	54
	55	boolean_t db_sstep_print;
	56	int db_loop_count;
	57	int db_call_depth;
	58
	59	int db_inst_count;
	60	int db_load_count;
	61	int db_store_count;
	62
	63	#ifndef db_set_single_step
	64	void db_set_single_step(/* db_regs_t regs /); /* forward */
	65	#endif
	66	#ifndef db_clear_single_step
	67	void db_clear_single_step(/* db_regs_t regs /);
	68	#endif
	69
	70	boolean_t
	71	db_stop_at_pc(is_breakpoint)
	72	boolean_t *is_breakpoint;
	73	{
	74	register db_addr_t pc;
	75	register db_breakpoint_t bkpt;
	76
	77	db_clear_single_step(DDB_REGS);
	78	db_clear_breakpoints();
	79	db_clear_watchpoints();
	80	pc = PC_REGS(DDB_REGS);
	81
	82	#ifdef FIXUP_PC_AFTER_BREAK
	83	if (*is_breakpoint) {
	84	/*
	85	* Breakpoint trap. Fix up the PC if the
	86	* machine requires it.
	87	*/
	88	FIXUP_PC_AFTER_BREAK
	89	pc = PC_REGS(DDB_REGS);
	90	}
	91	#endif
	92
	93	/*
	94	* Now check for a breakpoint at this address.
	95	*/
	96	bkpt = db_find_breakpoint_here(pc);
	97	if (bkpt) {
	98	if (--bkpt->count == 0) {
	99	bkpt->count = bkpt->init_count;
	100	*is_breakpoint = TRUE;
	101	return (TRUE); /* stop here */
	102	}
	103	} else if (*is_breakpoint) {
	104	ddb_regs.tf_eip += 1;
105	}
106
107	*is_breakpoint = FALSE;
108
109	if (db_run_mode == STEP_INVISIBLE) {
110	db_run_mode = STEP_CONTINUE;
111	return (FALSE); /* continue */
112	}
113	if (db_run_mode == STEP_COUNT) {
114	return (FALSE); /* continue */
115	}
116	if (db_run_mode == STEP_ONCE) {
117	if (--db_loop_count > 0) {
118	if (db_sstep_print) {
119	db_printf("\t\t");
120	db_print_loc_and_inst(pc);
121	db_printf("\n");
122	}
123	return (FALSE); /* continue */
124	}
125	}
126	if (db_run_mode == STEP_RETURN) {
127	db_expr_t ins = db_get_value(pc, sizeof(int), FALSE);
128
129	/* continue until matching return */
130
131	if (!inst_trap_return(ins) &&
132	(!inst_return(ins) \|\| --db_call_depth != 0)) {
133	if (db_sstep_print) {
134	if (inst_call(ins) \|\| inst_return(ins)) {
135	register int i;
136
137	db_printf("[after %6d] ", db_inst_count);
138	for (i = db_call_depth; --i > 0; )
139	db_printf(" ");
140	db_print_loc_and_inst(pc);
141	db_printf("\n");
142	}
143	}
144	if (inst_call(ins))
145	db_call_depth++;
146	return (FALSE); /* continue */
147	}
148	}
149	if (db_run_mode == STEP_CALLT) {
150	db_expr_t ins = db_get_value(pc, sizeof(int), FALSE);
151
152	/* continue until call or return */
153
154	if (!inst_call(ins) &&
155	!inst_return(ins) &&
156	!inst_trap_return(ins)) {
157	return (FALSE); /* continue */
158	}
159	}
160	db_run_mode = STEP_NONE;
161	return (TRUE);
162	}
163
164	void
165	db_restart_at_pc(watchpt)
166	boolean_t watchpt;
167	{
168	register db_addr_t pc = PC_REGS(DDB_REGS);
169
170	if ((db_run_mode == STEP_COUNT) \|\|
171	(db_run_mode == STEP_RETURN) \|\|
172	(db_run_mode == STEP_CALLT)) {
173	db_expr_t ins;
174
175	/*
176	* We are about to execute this instruction,
177	* so count it now.
178	*/
179
180	ins = db_get_value(pc, sizeof(int), FALSE);
181	db_inst_count++;
182	db_load_count += inst_load(ins);
183	db_store_count += inst_store(ins);
184	#ifdef SOFTWARE_SSTEP
185	/* XXX works on mips, but... */
186	if (inst_branch(ins) \|\| inst_call(ins)) {
187	ins = db_get_value(next_instr_address(pc,1),
188	sizeof(int), FALSE);
189	db_inst_count++;
190	db_load_count += inst_load(ins);
191	db_store_count += inst_store(ins);
192	}
193	#endif SOFTWARE_SSTEP
194	}
195
196	if (db_run_mode == STEP_CONTINUE) {
197	if (watchpt \|\| db_find_breakpoint_here(pc)) {
198	/*
199	* Step over breakpoint/watchpoint.
200	*/
201	db_run_mode = STEP_INVISIBLE;
202	db_set_single_step(DDB_REGS);
203	} else {
204	db_set_breakpoints();
205	db_set_watchpoints();
206	}
207	} else {
208	db_set_single_step(DDB_REGS);
209	}
210	}
211
212	void
213	db_single_step(regs)
214	db_regs_t *regs;
215	{
216	if (db_run_mode == STEP_CONTINUE) {
217	db_run_mode = STEP_INVISIBLE;
218	db_set_single_step(regs);
219	}
220	}
221
222	#ifdef SOFTWARE_SSTEP
223	/*
224	* Software implementation of single-stepping.
225	* If your machine does not have a trace mode
226	* similar to the vax or sun ones you can use
227	* this implementation, done for the mips.
228	* Just define the above conditional and provide
229	* the functions/macros defined below.
230	*
231	* extern boolean_t
232	* inst_branch(), returns true if the instruction might branch
233	* extern unsigned
234	* branch_taken(), return the address the instruction might
235	* branch to
236	* db_getreg_val(); return the value of a user register,
237	* as indicated in the hardware instruction
238	* encoding, e.g. 8 for r8
239	*
240	* next_instr_address(pc,bd) returns the address of the first
241	* instruction following the one at "pc",
242	* which is either in the taken path of
243	* the branch (bd==1) or not. This is
244	* for machines (mips) with branch delays.
245	*
246	* A single-step may involve at most 2 breakpoints -
247	* one for branch-not-taken and one for branch taken.
248	* If one of these addresses does not already have a breakpoint,
249	* we allocate a breakpoint and save it here.
250	* These breakpoints are deleted on return.
251	*/
252	db_breakpoint_t db_not_taken_bkpt = 0;
253	db_breakpoint_t db_taken_bkpt = 0;
254
255	void
256	db_set_single_step(regs)
257	register db_regs_t *regs;
258	{
259	db_addr_t pc = PC_REGS(regs);
260	register unsigned inst, brpc;
261
262	/*
263	* User was stopped at pc, e.g. the instruction
264	* at pc was not executed.
265	*/
266	inst = db_get_value(pc, sizeof(int), FALSE);
267	if (inst_branch(inst) \|\| inst_call(inst)) {
268	extern unsigned getreg_val();
269
270	brpc = branch_taken(inst, pc, getreg_val, regs);
271	if (brpc != pc) { /* self-branches are hopeless */
272	db_taken_bkpt = db_set_temp_breakpoint(brpc);
273	}
274	pc = next_instr_address(pc,1);
275	}
276	pc = next_instr_address(pc,0);
277	db_not_taken_bkpt = db_set_temp_breakpoint(pc);
278	}
279
280	void
281	db_clear_single_step(regs)
282	db_regs_t *regs;
283	{
284	register db_breakpoint_t bkpt;
285
286	if (db_taken_bkpt != 0) {
287	db_delete_temp_breakpoint(db_taken_bkpt);
288	db_taken_bkpt = 0;
289	}
290	if (db_not_taken_bkpt != 0) {
291	db_delete_temp_breakpoint(db_not_taken_bkpt);
292	db_not_taken_bkpt = 0;
293	}
294	}
295
296	#endif SOFTWARE_SSTEP
297
298	extern int db_cmd_loop_done;
299
300	/* single-step */
301	/ARGSUSED/
302	void
303	db_single_step_cmd(addr, have_addr, count, modif)
304	db_expr_t addr;
305	int have_addr;
306	db_expr_t count;
307	char * modif;
308	{
309	boolean_t print = FALSE;
310
311	if (count == -1)
312	count = 1;
313
314	if (modif[0] == 'p')
315	print = TRUE;
316
317	db_run_mode = STEP_ONCE;
318	db_loop_count = count;
319	db_sstep_print = print;
320	db_inst_count = 0;
321	db_load_count = 0;
322	db_store_count = 0;
323
324	db_cmd_loop_done = 1;
325	}
326
327	/* trace and print until call/return */
328	/ARGSUSED/
329	void
330	db_trace_until_call_cmd(addr, have_addr, count, modif)
331	db_expr_t addr;
332	int have_addr;
333	db_expr_t count;
334	char * modif;
335	{
336	boolean_t print = FALSE;
337
338	if (modif[0] == 'p')
339	print = TRUE;
340
341	db_run_mode = STEP_CALLT;
342	db_sstep_print = print;
343	db_inst_count = 0;
344	db_load_count = 0;
345	db_store_count = 0;
346
347	db_cmd_loop_done = 1;
348	}
349
350	/ARGSUSED/
351	void
352	db_trace_until_matching_cmd(addr, have_addr, count, modif)
353	db_expr_t addr;
354	int have_addr;
355	db_expr_t count;
356	char * modif;
357	{
358	boolean_t print = FALSE;
359
360	if (modif[0] == 'p')
361	print = TRUE;
362
363	db_run_mode = STEP_RETURN;
364	db_call_depth = 1;
365	db_sstep_print = print;
366	db_inst_count = 0;
367	db_load_count = 0;
368	db_store_count = 0;
369
370	db_cmd_loop_done = 1;
371	}
372
373	/* continue */
374	/ARGSUSED/
375	void
376	db_continue_cmd(addr, have_addr, count, modif)
377	db_expr_t addr;
378	int have_addr;
379	db_expr_t count;
380	char * modif;
381	{
382	if (modif[0] == 'c')
383	db_run_mode = STEP_COUNT;
384	else
385	db_run_mode = STEP_CONTINUE;
386	db_inst_count = 0;
387	db_load_count = 0;
388	db_store_count = 0;
389
390	db_cmd_loop_done = 1;
391	}