db_trace.c revision 1.12 1 /* $NetBSD: db_trace.c,v 1.12 2000/05/26 20:59:00 mhitch Exp $ */
2
3 /*
4 * Mach Operating System
5 * Copyright (c) 1993-1987 Carnegie Mellon University
6 * All Rights Reserved.
7 *
8 * Permission to use, copy, modify and distribute this software and its
9 * documentation is hereby granted, provided that both the copyright
10 * notice and this permission notice appear in all copies of the
11 * software, derivative works or modified versions, and any portions
12 * thereof, and that both notices appear in supporting documentation.
13 *
14 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
15 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
16 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
17 *
18 * Carnegie Mellon requests users of this software to return to
19 *
20 * Software Distribution Coordinator or Software.Distribution (at) CS.CMU.EDU
21 * School of Computer Science
22 * Carnegie Mellon University
23 * Pittsburgh PA 15213-3890
24 *
25 * any improvements or extensions that they make and grant Carnegie Mellon
26 * the rights to redistribute these changes.
27 */
28
29 #include <sys/types.h>
30 #include <vm/vm_param.h> /* XXX boolean_t */
31
32 #include <mips/mips_opcode.h>
33
34 #include <machine/param.h>
35 #include <machine/db_machdep.h>
36 #include <ddb/db_interface.h>
37 #include <ddb/db_output.h>
38 #include <ddb/db_variables.h>
39 #include <ddb/db_sym.h>
40
41 int __start __P((void)); /* lowest kernel code address */
42 vaddr_t getreg_val __P((db_expr_t regno));
43
44 #define REG_ARG(i) (4+i)
45 #define SAVES_RA(x) isa_spill((x),31)
46
47 #define KERN_SAVE_REG_IDX(vp) ( \
48 ((vp)->valuep >= (int *)(&((struct mips_saved_state *)0)->s0) && \
49 (vp)->valuep <= (int *)(&((struct mips_saved_state *)0)->s7))? \
50 vp->valuep - (int *)(&((struct mips_saved_state *)0)->s0): \
51 ((vp)->valuep >= (int *)(&((struct mips_saved_state *)0)->sp) && \
52 (vp)->valuep <= (int *)(&((struct mips_saved_state *)0)->ra))? \
53 ((vp)->valuep-(int *)(&((struct mips_saved_state *)0)->sp)) + \
54 ((int *)(&((struct mips_kernel_state *)0)->sp) - (int *)0): \
55 -1)
56
57 db_sym_t localsym __P((db_sym_t sym, boolean_t isreg, int *lex_level));
58
59 /*
60 * Machine register set.
61 */
62 struct mips_saved_state *db_cur_exc_frame = 0;
63
64 /*
65 * forward declarations
66 */
67 int print_exception_frame __P((struct mips_saved_state *fp,
68 unsigned epc));
69
70 /*XXX*/
71 void stacktrace_subr __P((int a0, int a1, int a2, int a3,
72 u_int pc, u_int sp, u_int fp, u_int ra,
73 void (*)(const char*, ...)));
74
75 /*
76 * Stack trace helper.
77 */
78 void db_mips_stack_trace __P((int count, vaddr_t stackp,
79 vaddr_t the_pc, vaddr_t the_ra, int flags,
80 vaddr_t kstackp));
81 int db_mips_variable_func __P((struct db_variable *vp, db_expr_t *valuep,
82 int db_var_fun));
83
84 #define DB_SETF_REGS db_mips_variable_func
85 #define DBREGS_REG()
86
87 struct db_variable db_regs[] = {
88 { "at", (long *)&ddb_regs.f_regs[AST], DB_SETF_REGS },
89 { "v0", (long *)&ddb_regs.f_regs[V0], DB_SETF_REGS },
90 { "v1", (long *)&ddb_regs.f_regs[V1], DB_SETF_REGS },
91 { "a0", (long *)&ddb_regs.f_regs[A0], DB_SETF_REGS },
92 { "a1", (long *)&ddb_regs.f_regs[A1], DB_SETF_REGS },
93 { "a2", (long *)&ddb_regs.f_regs[A2], DB_SETF_REGS },
94 { "a3", (long *)&ddb_regs.f_regs[A3], DB_SETF_REGS },
95 { "t0", (long *)&ddb_regs.f_regs[T0], DB_SETF_REGS },
96 { "t1", (long *)&ddb_regs.f_regs[T1], DB_SETF_REGS },
97 { "t2", (long *)&ddb_regs.f_regs[T2], DB_SETF_REGS },
98 { "t3", (long *)&ddb_regs.f_regs[T3], DB_SETF_REGS },
99 { "t4", (long *)&ddb_regs.f_regs[T4], DB_SETF_REGS },
100 { "t5", (long *)&ddb_regs.f_regs[T5], DB_SETF_REGS },
101 { "t6", (long *)&ddb_regs.f_regs[T6], DB_SETF_REGS },
102 { "t7", (long *)&ddb_regs.f_regs[T7], DB_SETF_REGS },
103 { "s0", (long *)&ddb_regs.f_regs[S0], DB_SETF_REGS },
104 { "s1", (long *)&ddb_regs.f_regs[S1], DB_SETF_REGS },
105 { "s2", (long *)&ddb_regs.f_regs[S2], DB_SETF_REGS },
106 { "s3", (long *)&ddb_regs.f_regs[S3], DB_SETF_REGS },
107 { "s4", (long *)&ddb_regs.f_regs[S4], DB_SETF_REGS },
108 { "s5", (long *)&ddb_regs.f_regs[S5], DB_SETF_REGS },
109 { "s6", (long *)&ddb_regs.f_regs[S6], DB_SETF_REGS },
110 { "s7", (long *)&ddb_regs.f_regs[S7], DB_SETF_REGS },
111 { "t8", (long *)&ddb_regs.f_regs[T8], DB_SETF_REGS },
112 { "t9", (long *)&ddb_regs.f_regs[T9], DB_SETF_REGS },
113 { "k0", (long *)&ddb_regs.f_regs[K0], DB_SETF_REGS },
114 { "k1", (long *)&ddb_regs.f_regs[K1], DB_SETF_REGS },
115 { "gp", (long *)&ddb_regs.f_regs[GP], DB_SETF_REGS },
116 { "sp", (long *)&ddb_regs.f_regs[SP], DB_SETF_REGS },
117 { "fp", (long *)&ddb_regs.f_regs[S8], DB_SETF_REGS }, /* frame ptr */
118 { "ra", (long *)&ddb_regs.f_regs[RA], DB_SETF_REGS },
119 { "sr", (long *)&ddb_regs.f_regs[SR], DB_SETF_REGS },
120 { "mdlo",(long *)&ddb_regs.f_regs[MULLO], DB_SETF_REGS },
121 { "mdhi",(long *)&ddb_regs.f_regs[MULHI], DB_SETF_REGS },
122 { "bad", (long *)&ddb_regs.f_regs[BADVADDR], DB_SETF_REGS },
123 { "cs", (long *)&ddb_regs.f_regs[CAUSE], DB_SETF_REGS },
124 { "pc", (long *)&ddb_regs.f_regs[PC], DB_SETF_REGS },
125 };
126 struct db_variable *db_eregs = db_regs + sizeof(db_regs)/sizeof(db_regs[0]);
127
128 void
129 db_stack_trace_print(addr, have_addr, count, modif, pr)
130 db_expr_t addr;
131 boolean_t have_addr;
132 db_expr_t count;
133 char *modif;
134 void (*pr) __P((const char *, ...));
135 {
136 #ifndef DDB_TRACE
137 stacktrace_subr(ddb_regs.f_regs[A0], ddb_regs.f_regs[A1],
138 ddb_regs.f_regs[A2], ddb_regs.f_regs[A3],
139 ddb_regs.f_regs[PC],
140 ddb_regs.f_regs[SP],
141 ddb_regs.f_regs[S8], /* non-virtual frame pointer */
142 ddb_regs.f_regs[RA],
143 pr);
144 #else
145 /*
146 * Imcomplete but practically useful stack backtrace.
147 */
148 #define MIPS_JR_RA 0x03e00008 /* instruction code for jr ra */
149 #define MIPS_JR_K0 0x03400008 /* instruction code for jr k0 */
150 #define MIPS_ERET 0x42000018 /* instruction code for eret */
151 unsigned va, pc, ra, sp, func;
152 int insn;
153 InstFmt i;
154 int stacksize;
155 db_addr_t offset;
156 char *name;
157 extern char verylocore[];
158
159 pc = ddb_regs.f_regs[PC];
160 sp = ddb_regs.f_regs[SP];
161 ra = ddb_regs.f_regs[RA];
162 do {
163 va = pc;
164 do {
165 va -= sizeof(int);
166 insn = *(int *)va;
167 if (insn == MIPS_ERET)
168 goto mips3_eret;
169 } while (insn != MIPS_JR_RA && insn != MIPS_JR_K0);
170 va += sizeof(int);
171 mips3_eret:
172 va += sizeof(int);
173 while (*(int *)va == 0x00000000)
174 va += sizeof(int);
175 func = va;
176 stacksize = 0;
177 do {
178 i.word = *(int *)va;
179 if (i.IType.op == OP_SW
180 && i.IType.rs == SP
181 && i.IType.rt == RA)
182 ra = *(int *)(sp + (short)i.IType.imm);
183 if (i.IType.op == OP_ADDIU
184 && i.IType.rs == SP
185 && i.IType.rt == SP)
186 stacksize = -(short)i.IType.imm;
187 va += sizeof(int);
188 } while (va < pc);
189
190 db_find_sym_and_offset(func, &name, &offset);
191 if (name == 0)
192 name = "?";
193 (*pr)("%s()+0x%x, called by %p, stack size %d\n",
194 name, pc - func, (void *)ra, stacksize);
195
196 if (ra == pc) {
197 (*pr)("-- loop? --\n");
198 return;
199 }
200 sp += stacksize;
201 pc = ra;
202 } while (pc > (unsigned)verylocore);
203 if (pc < 0x80000000)
204 (*pr)("-- user process --\n");
205 else
206 (*pr)("-- kernel entry --\n");
207 #endif
208 }
209
210 void
211 db_mips_stack_trace(count, stackp, the_pc, the_ra, flags, kstackp)
212 int count;
213 vaddr_t stackp, the_pc, the_ra;
214 int flags;
215 vaddr_t kstackp;
216 {
217 return;
218 }
219
220
221 int
222 db_mips_variable_func (struct db_variable *vp,
223 db_expr_t *valuep,
224 int db_var_fcn)
225 {
226 switch (db_var_fcn) {
227 case DB_VAR_GET:
228 *valuep = *(mips_reg_t *) vp->valuep;
229 break;
230 case DB_VAR_SET:
231 *(mips_reg_t *) vp->valuep = *valuep;
232 break;
233 }
234 return 0;
235 }
236