Commit | Line | Data |
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c906108c | 1 | /* Functions for manipulating expressions designed to be executed on the agent |
7b6bb8da | 2 | Copyright (C) 1998, 1999, 2000, 2007, 2008, 2009, 2010, 2011 |
0fb0cc75 | 3 | Free Software Foundation, Inc. |
c906108c | 4 | |
c5aa993b | 5 | This file is part of GDB. |
c906108c | 6 | |
c5aa993b JM |
7 | This program is free software; you can redistribute it and/or modify |
8 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 9 | the Free Software Foundation; either version 3 of the License, or |
c5aa993b | 10 | (at your option) any later version. |
c906108c | 11 | |
c5aa993b JM |
12 | This program is distributed in the hope that it will be useful, |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
c906108c | 16 | |
c5aa993b | 17 | You should have received a copy of the GNU General Public License |
a9762ec7 | 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
c906108c | 19 | |
c906108c SS |
20 | /* Despite what the above comment says about this file being part of |
21 | GDB, we would like to keep these functions free of GDB | |
22 | dependencies, since we want to be able to use them in contexts | |
23 | outside of GDB (test suites, the stub, etc.) */ | |
24 | ||
25 | #include "defs.h" | |
26 | #include "ax.h" | |
27 | ||
7a292a7a | 28 | #include "value.h" |
b66d6d2e | 29 | #include "gdb_string.h" |
7a292a7a | 30 | |
175ff332 HZ |
31 | #include "user-regs.h" |
32 | ||
a14ed312 | 33 | static void grow_expr (struct agent_expr *x, int n); |
392a587b | 34 | |
a14ed312 | 35 | static void append_const (struct agent_expr *x, LONGEST val, int n); |
392a587b | 36 | |
a14ed312 | 37 | static LONGEST read_const (struct agent_expr *x, int o, int n); |
392a587b | 38 | |
a14ed312 | 39 | static void generic_ext (struct agent_expr *x, enum agent_op op, int n); |
c906108c SS |
40 | \f |
41 | /* Functions for building expressions. */ | |
42 | ||
43 | /* Allocate a new, empty agent expression. */ | |
44 | struct agent_expr * | |
35c9c7ba | 45 | new_agent_expr (struct gdbarch *gdbarch, CORE_ADDR scope) |
c906108c SS |
46 | { |
47 | struct agent_expr *x = xmalloc (sizeof (*x)); | |
35c9c7ba | 48 | |
c5aa993b | 49 | x->len = 0; |
c906108c SS |
50 | x->size = 1; /* Change this to a larger value once |
51 | reallocation code is tested. */ | |
c5aa993b | 52 | x->buf = xmalloc (x->size); |
35c9c7ba SS |
53 | |
54 | x->gdbarch = gdbarch; | |
c906108c SS |
55 | x->scope = scope; |
56 | ||
35c9c7ba SS |
57 | /* Bit vector for registers used. */ |
58 | x->reg_mask_len = 1; | |
59 | x->reg_mask = xmalloc (x->reg_mask_len * sizeof (x->reg_mask[0])); | |
60 | memset (x->reg_mask, 0, x->reg_mask_len * sizeof (x->reg_mask[0])); | |
61 | ||
c906108c SS |
62 | return x; |
63 | } | |
64 | ||
65 | /* Free a agent expression. */ | |
66 | void | |
fba45db2 | 67 | free_agent_expr (struct agent_expr *x) |
c906108c | 68 | { |
b8c9b27d | 69 | xfree (x->buf); |
35c9c7ba | 70 | xfree (x->reg_mask); |
b8c9b27d | 71 | xfree (x); |
c906108c SS |
72 | } |
73 | ||
f23d52e0 AC |
74 | static void |
75 | do_free_agent_expr_cleanup (void *x) | |
76 | { | |
77 | free_agent_expr (x); | |
78 | } | |
79 | ||
80 | struct cleanup * | |
81 | make_cleanup_free_agent_expr (struct agent_expr *x) | |
82 | { | |
83 | return make_cleanup (do_free_agent_expr_cleanup, x); | |
84 | } | |
85 | ||
c906108c SS |
86 | |
87 | /* Make sure that X has room for at least N more bytes. This doesn't | |
88 | affect the length, just the allocated size. */ | |
89 | static void | |
fba45db2 | 90 | grow_expr (struct agent_expr *x, int n) |
c906108c SS |
91 | { |
92 | if (x->len + n > x->size) | |
93 | { | |
94 | x->size *= 2; | |
95 | if (x->size < x->len + n) | |
96 | x->size = x->len + n + 10; | |
97 | x->buf = xrealloc (x->buf, x->size); | |
98 | } | |
99 | } | |
100 | ||
101 | ||
102 | /* Append the low N bytes of VAL as an N-byte integer to the | |
103 | expression X, in big-endian order. */ | |
104 | static void | |
fba45db2 | 105 | append_const (struct agent_expr *x, LONGEST val, int n) |
c906108c SS |
106 | { |
107 | int i; | |
108 | ||
109 | grow_expr (x, n); | |
110 | for (i = n - 1; i >= 0; i--) | |
111 | { | |
112 | x->buf[x->len + i] = val & 0xff; | |
113 | val >>= 8; | |
114 | } | |
115 | x->len += n; | |
116 | } | |
117 | ||
118 | ||
119 | /* Extract an N-byte big-endian unsigned integer from expression X at | |
120 | offset O. */ | |
121 | static LONGEST | |
fba45db2 | 122 | read_const (struct agent_expr *x, int o, int n) |
c906108c SS |
123 | { |
124 | int i; | |
125 | LONGEST accum = 0; | |
126 | ||
127 | /* Make sure we're not reading off the end of the expression. */ | |
128 | if (o + n > x->len) | |
3d263c1d | 129 | error (_("GDB bug: ax-general.c (read_const): incomplete constant")); |
c906108c SS |
130 | |
131 | for (i = 0; i < n; i++) | |
132 | accum = (accum << 8) | x->buf[o + i]; | |
c5aa993b | 133 | |
c906108c SS |
134 | return accum; |
135 | } | |
136 | ||
137 | ||
138 | /* Append a simple operator OP to EXPR. */ | |
139 | void | |
fba45db2 | 140 | ax_simple (struct agent_expr *x, enum agent_op op) |
c906108c SS |
141 | { |
142 | grow_expr (x, 1); | |
143 | x->buf[x->len++] = op; | |
144 | } | |
145 | ||
146 | ||
147 | /* Append a sign-extension or zero-extension instruction to EXPR, to | |
148 | extend an N-bit value. */ | |
149 | static void | |
fba45db2 | 150 | generic_ext (struct agent_expr *x, enum agent_op op, int n) |
c906108c SS |
151 | { |
152 | /* N must fit in a byte. */ | |
153 | if (n < 0 || n > 255) | |
3d263c1d | 154 | error (_("GDB bug: ax-general.c (generic_ext): bit count out of range")); |
c906108c SS |
155 | /* That had better be enough range. */ |
156 | if (sizeof (LONGEST) * 8 > 255) | |
3d263c1d | 157 | error (_("GDB bug: ax-general.c (generic_ext): opcode has inadequate range")); |
c906108c SS |
158 | |
159 | grow_expr (x, 2); | |
160 | x->buf[x->len++] = op; | |
161 | x->buf[x->len++] = n; | |
162 | } | |
163 | ||
164 | ||
165 | /* Append a sign-extension instruction to EXPR, to extend an N-bit value. */ | |
166 | void | |
fba45db2 | 167 | ax_ext (struct agent_expr *x, int n) |
c906108c SS |
168 | { |
169 | generic_ext (x, aop_ext, n); | |
170 | } | |
171 | ||
172 | ||
173 | /* Append a zero-extension instruction to EXPR, to extend an N-bit value. */ | |
174 | void | |
fba45db2 | 175 | ax_zero_ext (struct agent_expr *x, int n) |
c906108c SS |
176 | { |
177 | generic_ext (x, aop_zero_ext, n); | |
178 | } | |
179 | ||
180 | ||
181 | /* Append a trace_quick instruction to EXPR, to record N bytes. */ | |
182 | void | |
fba45db2 | 183 | ax_trace_quick (struct agent_expr *x, int n) |
c906108c SS |
184 | { |
185 | /* N must fit in a byte. */ | |
186 | if (n < 0 || n > 255) | |
3d263c1d | 187 | error (_("GDB bug: ax-general.c (ax_trace_quick): size out of range for trace_quick")); |
c906108c SS |
188 | |
189 | grow_expr (x, 2); | |
190 | x->buf[x->len++] = aop_trace_quick; | |
191 | x->buf[x->len++] = n; | |
192 | } | |
193 | ||
194 | ||
195 | /* Append a goto op to EXPR. OP is the actual op (must be aop_goto or | |
196 | aop_if_goto). We assume we don't know the target offset yet, | |
197 | because it's probably a forward branch, so we leave space in EXPR | |
198 | for the target, and return the offset in EXPR of that space, so we | |
199 | can backpatch it once we do know the target offset. Use ax_label | |
200 | to do the backpatching. */ | |
c5aa993b | 201 | int |
fba45db2 | 202 | ax_goto (struct agent_expr *x, enum agent_op op) |
c906108c SS |
203 | { |
204 | grow_expr (x, 3); | |
205 | x->buf[x->len + 0] = op; | |
206 | x->buf[x->len + 1] = 0xff; | |
207 | x->buf[x->len + 2] = 0xff; | |
208 | x->len += 3; | |
209 | return x->len - 2; | |
210 | } | |
211 | ||
212 | /* Suppose a given call to ax_goto returns some value PATCH. When you | |
213 | know the offset TARGET that goto should jump to, call | |
c5aa993b | 214 | ax_label (EXPR, PATCH, TARGET) |
c906108c SS |
215 | to patch TARGET into the ax_goto instruction. */ |
216 | void | |
fba45db2 | 217 | ax_label (struct agent_expr *x, int patch, int target) |
c906108c SS |
218 | { |
219 | /* Make sure the value is in range. Don't accept 0xffff as an | |
220 | offset; that's our magic sentinel value for unpatched branches. */ | |
221 | if (target < 0 || target >= 0xffff) | |
3d263c1d | 222 | error (_("GDB bug: ax-general.c (ax_label): label target out of range")); |
c5aa993b | 223 | |
c906108c SS |
224 | x->buf[patch] = (target >> 8) & 0xff; |
225 | x->buf[patch + 1] = target & 0xff; | |
226 | } | |
227 | ||
228 | ||
229 | /* Assemble code to push a constant on the stack. */ | |
230 | void | |
fba45db2 | 231 | ax_const_l (struct agent_expr *x, LONGEST l) |
c906108c SS |
232 | { |
233 | static enum agent_op ops[] | |
c5aa993b JM |
234 | = |
235 | {aop_const8, aop_const16, aop_const32, aop_const64}; | |
c906108c SS |
236 | int size; |
237 | int op; | |
238 | ||
239 | /* How big is the number? 'op' keeps track of which opcode to use. | |
240 | Notice that we don't really care whether the original number was | |
241 | signed or unsigned; we always reproduce the value exactly, and | |
242 | use the shortest representation. */ | |
243 | for (op = 0, size = 8; size < 64; size *= 2, op++) | |
44a81774 | 244 | { |
cf3e25ca | 245 | LONGEST lim = ((LONGEST) 1) << (size - 1); |
44a81774 JB |
246 | |
247 | if (-lim <= l && l <= lim - 1) | |
248 | break; | |
249 | } | |
c906108c | 250 | |
0e2de366 | 251 | /* Emit the right opcode... */ |
c906108c SS |
252 | ax_simple (x, ops[op]); |
253 | ||
254 | /* Emit the low SIZE bytes as an unsigned number. We know that | |
255 | sign-extending this will yield l. */ | |
256 | append_const (x, l, size / 8); | |
257 | ||
258 | /* Now, if it was negative, and not full-sized, sign-extend it. */ | |
259 | if (l < 0 && size < 64) | |
260 | ax_ext (x, size); | |
261 | } | |
262 | ||
263 | ||
264 | void | |
fba45db2 | 265 | ax_const_d (struct agent_expr *x, LONGEST d) |
c906108c SS |
266 | { |
267 | /* FIXME: floating-point support not present yet. */ | |
3d263c1d | 268 | error (_("GDB bug: ax-general.c (ax_const_d): floating point not supported yet")); |
c906108c SS |
269 | } |
270 | ||
271 | ||
272 | /* Assemble code to push the value of register number REG on the | |
273 | stack. */ | |
c5aa993b | 274 | void |
fba45db2 | 275 | ax_reg (struct agent_expr *x, int reg) |
c906108c | 276 | { |
175ff332 HZ |
277 | if (reg >= gdbarch_num_regs (x->gdbarch)) |
278 | { | |
279 | /* This is a pseudo-register. */ | |
280 | if (!gdbarch_ax_pseudo_register_push_stack_p (x->gdbarch)) | |
281 | error (_("'%s' is a pseudo-register; " | |
282 | "GDB cannot yet trace its contents."), | |
283 | user_reg_map_regnum_to_name (x->gdbarch, reg)); | |
284 | if (gdbarch_ax_pseudo_register_push_stack (x->gdbarch, x, reg)) | |
285 | error (_("Trace '%s' failed."), | |
286 | user_reg_map_regnum_to_name (x->gdbarch, reg)); | |
287 | } | |
288 | else | |
289 | { | |
290 | /* Make sure the register number is in range. */ | |
291 | if (reg < 0 || reg > 0xffff) | |
292 | error (_("GDB bug: ax-general.c (ax_reg): register number out of range")); | |
293 | grow_expr (x, 3); | |
294 | x->buf[x->len] = aop_reg; | |
295 | x->buf[x->len + 1] = (reg >> 8) & 0xff; | |
296 | x->buf[x->len + 2] = (reg) & 0xff; | |
297 | x->len += 3; | |
298 | } | |
c906108c | 299 | } |
f61e138d SS |
300 | |
301 | /* Assemble code to operate on a trace state variable. */ | |
302 | ||
303 | void | |
304 | ax_tsv (struct agent_expr *x, enum agent_op op, int num) | |
305 | { | |
306 | /* Make sure the tsv number is in range. */ | |
307 | if (num < 0 || num > 0xffff) | |
308 | internal_error (__FILE__, __LINE__, _("ax-general.c (ax_tsv): variable number is %d, out of range"), num); | |
309 | ||
310 | grow_expr (x, 3); | |
311 | x->buf[x->len] = op; | |
312 | x->buf[x->len + 1] = (num >> 8) & 0xff; | |
313 | x->buf[x->len + 2] = (num) & 0xff; | |
314 | x->len += 3; | |
315 | } | |
c5aa993b | 316 | \f |
c906108c SS |
317 | |
318 | ||
c906108c SS |
319 | /* Functions for disassembling agent expressions, and otherwise |
320 | debugging the expression compiler. */ | |
321 | ||
c5aa993b JM |
322 | struct aop_map aop_map[] = |
323 | { | |
324 | {0, 0, 0, 0, 0}, | |
325 | {"float", 0, 0, 0, 0}, /* 0x01 */ | |
326 | {"add", 0, 0, 2, 1}, /* 0x02 */ | |
327 | {"sub", 0, 0, 2, 1}, /* 0x03 */ | |
328 | {"mul", 0, 0, 2, 1}, /* 0x04 */ | |
329 | {"div_signed", 0, 0, 2, 1}, /* 0x05 */ | |
330 | {"div_unsigned", 0, 0, 2, 1}, /* 0x06 */ | |
331 | {"rem_signed", 0, 0, 2, 1}, /* 0x07 */ | |
332 | {"rem_unsigned", 0, 0, 2, 1}, /* 0x08 */ | |
333 | {"lsh", 0, 0, 2, 1}, /* 0x09 */ | |
334 | {"rsh_signed", 0, 0, 2, 1}, /* 0x0a */ | |
335 | {"rsh_unsigned", 0, 0, 2, 1}, /* 0x0b */ | |
336 | {"trace", 0, 0, 2, 0}, /* 0x0c */ | |
337 | {"trace_quick", 1, 0, 1, 1}, /* 0x0d */ | |
338 | {"log_not", 0, 0, 1, 1}, /* 0x0e */ | |
339 | {"bit_and", 0, 0, 2, 1}, /* 0x0f */ | |
340 | {"bit_or", 0, 0, 2, 1}, /* 0x10 */ | |
341 | {"bit_xor", 0, 0, 2, 1}, /* 0x11 */ | |
342 | {"bit_not", 0, 0, 1, 1}, /* 0x12 */ | |
343 | {"equal", 0, 0, 2, 1}, /* 0x13 */ | |
344 | {"less_signed", 0, 0, 2, 1}, /* 0x14 */ | |
345 | {"less_unsigned", 0, 0, 2, 1}, /* 0x15 */ | |
346 | {"ext", 1, 0, 1, 1}, /* 0x16 */ | |
347 | {"ref8", 0, 8, 1, 1}, /* 0x17 */ | |
348 | {"ref16", 0, 16, 1, 1}, /* 0x18 */ | |
349 | {"ref32", 0, 32, 1, 1}, /* 0x19 */ | |
350 | {"ref64", 0, 64, 1, 1}, /* 0x1a */ | |
351 | {"ref_float", 0, 0, 1, 1}, /* 0x1b */ | |
352 | {"ref_double", 0, 0, 1, 1}, /* 0x1c */ | |
353 | {"ref_long_double", 0, 0, 1, 1}, /* 0x1d */ | |
354 | {"l_to_d", 0, 0, 1, 1}, /* 0x1e */ | |
355 | {"d_to_l", 0, 0, 1, 1}, /* 0x1f */ | |
356 | {"if_goto", 2, 0, 1, 0}, /* 0x20 */ | |
357 | {"goto", 2, 0, 0, 0}, /* 0x21 */ | |
358 | {"const8", 1, 8, 0, 1}, /* 0x22 */ | |
359 | {"const16", 2, 16, 0, 1}, /* 0x23 */ | |
360 | {"const32", 4, 32, 0, 1}, /* 0x24 */ | |
361 | {"const64", 8, 64, 0, 1}, /* 0x25 */ | |
362 | {"reg", 2, 0, 0, 1}, /* 0x26 */ | |
363 | {"end", 0, 0, 0, 0}, /* 0x27 */ | |
364 | {"dup", 0, 0, 1, 2}, /* 0x28 */ | |
365 | {"pop", 0, 0, 1, 0}, /* 0x29 */ | |
366 | {"zero_ext", 1, 0, 1, 1}, /* 0x2a */ | |
367 | {"swap", 0, 0, 2, 2}, /* 0x2b */ | |
f61e138d SS |
368 | {"getv", 2, 0, 0, 1}, /* 0x2c */ |
369 | {"setv", 2, 0, 0, 1}, /* 0x2d */ | |
370 | {"tracev", 2, 0, 0, 1}, /* 0x2e */ | |
c5aa993b JM |
371 | {0, 0, 0, 0, 0}, /* 0x2f */ |
372 | {"trace16", 2, 0, 1, 1}, /* 0x30 */ | |
c906108c SS |
373 | }; |
374 | ||
375 | ||
376 | /* Disassemble the expression EXPR, writing to F. */ | |
377 | void | |
fba45db2 | 378 | ax_print (struct ui_file *f, struct agent_expr *x) |
c906108c SS |
379 | { |
380 | int i; | |
381 | int is_float = 0; | |
382 | ||
35c9c7ba SS |
383 | fprintf_filtered (f, _("Scope: %s\n"), paddress (x->gdbarch, x->scope)); |
384 | fprintf_filtered (f, _("Reg mask:")); | |
385 | for (i = 0; i < x->reg_mask_len; ++i) | |
386 | fprintf_filtered (f, _(" %02x"), x->reg_mask[i]); | |
387 | fprintf_filtered (f, _("\n")); | |
388 | ||
c906108c SS |
389 | /* Check the size of the name array against the number of entries in |
390 | the enum, to catch additions that people didn't sync. */ | |
391 | if ((sizeof (aop_map) / sizeof (aop_map[0])) | |
392 | != aop_last) | |
3d263c1d | 393 | error (_("GDB bug: ax-general.c (ax_print): opcode map out of sync")); |
c5aa993b JM |
394 | |
395 | for (i = 0; i < x->len;) | |
c906108c SS |
396 | { |
397 | enum agent_op op = x->buf[i]; | |
398 | ||
399 | if (op >= (sizeof (aop_map) / sizeof (aop_map[0])) | |
c5aa993b | 400 | || !aop_map[op].name) |
c906108c | 401 | { |
3d263c1d | 402 | fprintf_filtered (f, _("%3d <bad opcode %02x>\n"), i, op); |
c906108c SS |
403 | i++; |
404 | continue; | |
405 | } | |
406 | if (i + 1 + aop_map[op].op_size > x->len) | |
407 | { | |
3d263c1d | 408 | fprintf_filtered (f, _("%3d <incomplete opcode %s>\n"), |
c906108c SS |
409 | i, aop_map[op].name); |
410 | break; | |
411 | } | |
412 | ||
413 | fprintf_filtered (f, "%3d %s", i, aop_map[op].name); | |
414 | if (aop_map[op].op_size > 0) | |
415 | { | |
416 | fputs_filtered (" ", f); | |
c5aa993b | 417 | |
c906108c SS |
418 | print_longest (f, 'd', 0, |
419 | read_const (x, i + 1, aop_map[op].op_size)); | |
420 | } | |
421 | fprintf_filtered (f, "\n"); | |
422 | i += 1 + aop_map[op].op_size; | |
423 | ||
424 | is_float = (op == aop_float); | |
425 | } | |
426 | } | |
427 | ||
35c9c7ba SS |
428 | /* Add register REG to the register mask for expression AX. */ |
429 | void | |
430 | ax_reg_mask (struct agent_expr *ax, int reg) | |
431 | { | |
175ff332 | 432 | if (reg >= gdbarch_num_regs (ax->gdbarch)) |
35c9c7ba | 433 | { |
175ff332 HZ |
434 | /* This is a pseudo-register. */ |
435 | if (!gdbarch_ax_pseudo_register_collect_p (ax->gdbarch)) | |
436 | error (_("'%s' is a pseudo-register; " | |
437 | "GDB cannot yet trace its contents."), | |
438 | user_reg_map_regnum_to_name (ax->gdbarch, reg)); | |
439 | if (gdbarch_ax_pseudo_register_collect (ax->gdbarch, ax, reg)) | |
440 | error (_("Trace '%s' failed."), | |
441 | user_reg_map_regnum_to_name (ax->gdbarch, reg)); | |
442 | } | |
443 | else | |
444 | { | |
445 | int byte = reg / 8; | |
446 | ||
447 | /* Grow the bit mask if necessary. */ | |
448 | if (byte >= ax->reg_mask_len) | |
449 | { | |
450 | /* It's not appropriate to double here. This isn't a | |
451 | string buffer. */ | |
452 | int new_len = byte + 1; | |
453 | unsigned char *new_reg_mask = xrealloc (ax->reg_mask, | |
454 | new_len | |
455 | * sizeof (ax->reg_mask[0])); | |
456 | memset (new_reg_mask + ax->reg_mask_len, 0, | |
457 | (new_len - ax->reg_mask_len) * sizeof (ax->reg_mask[0])); | |
458 | ax->reg_mask_len = new_len; | |
459 | ax->reg_mask = new_reg_mask; | |
460 | } | |
461 | ||
462 | ax->reg_mask[byte] |= 1 << (reg % 8); | |
35c9c7ba | 463 | } |
35c9c7ba SS |
464 | } |
465 | ||
466 | /* Given an agent expression AX, fill in requirements and other descriptive | |
467 | bits. */ | |
c906108c | 468 | void |
35c9c7ba | 469 | ax_reqs (struct agent_expr *ax) |
c906108c SS |
470 | { |
471 | int i; | |
472 | int height; | |
473 | ||
3d269a59 JB |
474 | /* Jump target table. targets[i] is non-zero iff we have found a |
475 | jump to offset i. */ | |
c906108c SS |
476 | char *targets = (char *) alloca (ax->len * sizeof (targets[0])); |
477 | ||
3d269a59 JB |
478 | /* Instruction boundary table. boundary[i] is non-zero iff our scan |
479 | has reached an instruction starting at offset i. */ | |
c906108c SS |
480 | char *boundary = (char *) alloca (ax->len * sizeof (boundary[0])); |
481 | ||
3d269a59 | 482 | /* Stack height record. If either targets[i] or boundary[i] is |
c906108c SS |
483 | non-zero, heights[i] is the height the stack should have before |
484 | executing the bytecode at that point. */ | |
485 | int *heights = (int *) alloca (ax->len * sizeof (heights[0])); | |
486 | ||
487 | /* Pointer to a description of the present op. */ | |
488 | struct aop_map *op; | |
489 | ||
c906108c SS |
490 | memset (targets, 0, ax->len * sizeof (targets[0])); |
491 | memset (boundary, 0, ax->len * sizeof (boundary[0])); | |
492 | ||
35c9c7ba SS |
493 | ax->max_height = ax->min_height = height = 0; |
494 | ax->flaw = agent_flaw_none; | |
495 | ax->max_data_size = 0; | |
c906108c SS |
496 | |
497 | for (i = 0; i < ax->len; i += 1 + op->op_size) | |
498 | { | |
499 | if (ax->buf[i] > (sizeof (aop_map) / sizeof (aop_map[0]))) | |
500 | { | |
35c9c7ba | 501 | ax->flaw = agent_flaw_bad_instruction; |
c906108c SS |
502 | return; |
503 | } | |
504 | ||
505 | op = &aop_map[ax->buf[i]]; | |
506 | ||
c5aa993b | 507 | if (!op->name) |
c906108c | 508 | { |
35c9c7ba | 509 | ax->flaw = agent_flaw_bad_instruction; |
c906108c SS |
510 | return; |
511 | } | |
c5aa993b | 512 | |
c906108c SS |
513 | if (i + 1 + op->op_size > ax->len) |
514 | { | |
35c9c7ba | 515 | ax->flaw = agent_flaw_incomplete_instruction; |
c906108c SS |
516 | return; |
517 | } | |
518 | ||
3d269a59 JB |
519 | /* If this instruction is a forward jump target, does the |
520 | current stack height match the stack height at the jump | |
521 | source? */ | |
c906108c SS |
522 | if (targets[i] && (heights[i] != height)) |
523 | { | |
35c9c7ba | 524 | ax->flaw = agent_flaw_height_mismatch; |
c906108c SS |
525 | return; |
526 | } | |
527 | ||
528 | boundary[i] = 1; | |
529 | heights[i] = height; | |
530 | ||
531 | height -= op->consumed; | |
35c9c7ba SS |
532 | if (height < ax->min_height) |
533 | ax->min_height = height; | |
c906108c | 534 | height += op->produced; |
35c9c7ba SS |
535 | if (height > ax->max_height) |
536 | ax->max_height = height; | |
c906108c | 537 | |
35c9c7ba SS |
538 | if (op->data_size > ax->max_data_size) |
539 | ax->max_data_size = op->data_size; | |
c906108c SS |
540 | |
541 | /* For jump instructions, check that the target is a valid | |
c5aa993b JM |
542 | offset. If it is, record the fact that that location is a |
543 | jump target, and record the height we expect there. */ | |
c906108c SS |
544 | if (aop_goto == op - aop_map |
545 | || aop_if_goto == op - aop_map) | |
546 | { | |
547 | int target = read_const (ax, i + 1, 2); | |
548 | if (target < 0 || target >= ax->len) | |
549 | { | |
35c9c7ba | 550 | ax->flaw = agent_flaw_bad_jump; |
c906108c SS |
551 | return; |
552 | } | |
3d269a59 JB |
553 | |
554 | /* Do we have any information about what the stack height | |
555 | should be at the target? */ | |
556 | if (targets[target] || boundary[target]) | |
c906108c | 557 | { |
3d269a59 | 558 | if (heights[target] != height) |
c906108c | 559 | { |
35c9c7ba | 560 | ax->flaw = agent_flaw_height_mismatch; |
c906108c SS |
561 | return; |
562 | } | |
563 | } | |
3d269a59 JB |
564 | |
565 | /* Record the target, along with the stack height we expect. */ | |
566 | targets[target] = 1; | |
567 | heights[target] = height; | |
c906108c | 568 | } |
c5aa993b | 569 | |
c906108c SS |
570 | /* For unconditional jumps with a successor, check that the |
571 | successor is a target, and pick up its stack height. */ | |
572 | if (aop_goto == op - aop_map | |
573 | && i + 3 < ax->len) | |
574 | { | |
c5aa993b | 575 | if (!targets[i + 3]) |
c906108c | 576 | { |
35c9c7ba | 577 | ax->flaw = agent_flaw_hole; |
c906108c SS |
578 | return; |
579 | } | |
580 | ||
581 | height = heights[i + 3]; | |
582 | } | |
583 | ||
584 | /* For reg instructions, record the register in the bit mask. */ | |
585 | if (aop_reg == op - aop_map) | |
586 | { | |
587 | int reg = read_const (ax, i + 1, 2); | |
c906108c | 588 | |
35c9c7ba | 589 | ax_reg_mask (ax, reg); |
c906108c SS |
590 | } |
591 | } | |
592 | ||
593 | /* Check that all the targets are on boundaries. */ | |
594 | for (i = 0; i < ax->len; i++) | |
595 | if (targets[i] && !boundary[i]) | |
596 | { | |
35c9c7ba | 597 | ax->flaw = agent_flaw_bad_jump; |
c906108c SS |
598 | return; |
599 | } | |
600 | ||
35c9c7ba | 601 | ax->final_height = height; |
c906108c | 602 | } |