hsdis.c revision 6010:abec000618bf
1163519Simp/*
2163519Simp * Copyright (c) 2008, 2013, Oracle and/or its affiliates. All rights reserved.
3319182Sngie * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4163519Simp *
5163519Simp * This code is free software; you can redistribute it and/or modify it
6234524Smarius * under the terms of the GNU General Public License version 2 only, as
7163519Simp * published by the Free Software Foundation.
8163519Simp *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25/* hsdis.c -- dump a range of addresses as native instructions
26   This implements the plugin protocol required by the
27   HotSpot PrintAssembly option.
28*/
29
30#include <config.h> /* required by bfd.h */
31#include <libiberty.h>
32#include <bfd.h>
33#include <dis-asm.h>
34#include <inttypes.h>
35#include <string.h>
36#include <errno.h>
37#include "hsdis.h"
38
39#ifndef bool
40#define bool int
41#define true 1
42#define false 0
43#endif /*bool*/
44
45/* short names for stuff in hsdis.h */
46typedef decode_instructions_event_callback_ftype  event_callback_t;
47typedef decode_instructions_printf_callback_ftype printf_callback_t;
48
49/* disassemble_info.application_data object */
50struct hsdis_app_data {
51  /* virtual address of data */
52  uintptr_t start_va, end_va;
53  /* the instructions to be decoded */
54  unsigned char* buffer;
55  uintptr_t length;
56  event_callback_t  event_callback;  void* event_stream;
57  printf_callback_t printf_callback; void* printf_stream;
58  bool losing;
59  bool do_newline;
60
61  /* the architecture being disassembled */
62  const char* arch_name;
63  const bfd_arch_info_type* arch_info;
64
65  /* the disassembler we are going to use: */
66  disassembler_ftype      dfn;
67  struct disassemble_info dinfo; /* the actual struct! */
68
69  char mach_option[64];
70  char insn_options[256];
71};
72
73static void* decode(struct hsdis_app_data* app_data, const char* options);
74
75#define DECL_APP_DATA(dinfo) \
76  struct hsdis_app_data* app_data = (struct hsdis_app_data*) (dinfo)->application_data
77
78#define DECL_EVENT_CALLBACK(app_data) \
79  event_callback_t  event_callback = (app_data)->event_callback; \
80  void*             event_stream   = (app_data)->event_stream
81
82#define DECL_PRINTF_CALLBACK(app_data) \
83  printf_callback_t  printf_callback = (app_data)->printf_callback; \
84  void*              printf_stream   = (app_data)->printf_stream
85
86
87static void print_help(struct hsdis_app_data* app_data,
88                       const char* msg, const char* arg);
89static void setup_app_data(struct hsdis_app_data* app_data,
90                           const char* options);
91static const char* format_insn_close(const char* close,
92                                     disassemble_info* dinfo,
93                                     char* buf, size_t bufsize);
94
95void*
96#ifdef DLL_ENTRY
97  DLL_ENTRY
98#endif
99decode_instructions_virtual(uintptr_t start_va, uintptr_t end_va,
100                            unsigned char* buffer, uintptr_t length,
101                            event_callback_t  event_callback_arg,  void* event_stream_arg,
102                            printf_callback_t printf_callback_arg, void* printf_stream_arg,
103                            const char* options, int newline) {
104  struct hsdis_app_data app_data;
105  memset(&app_data, 0, sizeof(app_data));
106  app_data.start_va    = start_va;
107  app_data.end_va      = end_va;
108  app_data.buffer = buffer;
109  app_data.length = length;
110  app_data.event_callback  = event_callback_arg;
111  app_data.event_stream    = event_stream_arg;
112  app_data.printf_callback = printf_callback_arg;
113  app_data.printf_stream   = printf_stream_arg;
114  app_data.do_newline = newline == 0 ? false : true;
115
116  return decode(&app_data, options);
117}
118
119/* This is the compatability interface for older version of hotspot */
120void*
121#ifdef DLL_ENTRY
122  DLL_ENTRY
123#endif
124decode_instructions(void* start_pv, void* end_pv,
125                    event_callback_t  event_callback_arg,  void* event_stream_arg,
126                    printf_callback_t printf_callback_arg, void* printf_stream_arg,
127                    const char* options) {
128  decode_instructions_virtual((uintptr_t)start_pv,
129                             (uintptr_t)end_pv,
130                             (unsigned char*)start_pv,
131                             (uintptr_t)end_pv - (uintptr_t)start_pv,
132                             event_callback_arg,
133                             event_stream_arg,
134                             printf_callback_arg,
135                             printf_stream_arg,
136                             options, false);
137}
138
139static void* decode(struct hsdis_app_data* app_data, const char* options) {
140  setup_app_data(app_data, options);
141  char buf[128];
142
143  {
144    /* now reload everything from app_data: */
145    DECL_EVENT_CALLBACK(app_data);
146    DECL_PRINTF_CALLBACK(app_data);
147    uintptr_t start = app_data->start_va;
148    uintptr_t end   = app_data->end_va;
149    uintptr_t p     = start;
150
151    (*event_callback)(event_stream, "insns", (void*)start);
152
153    (*event_callback)(event_stream, "mach name='%s'",
154                      (void*) app_data->arch_info->printable_name);
155    if (app_data->dinfo.bytes_per_line != 0) {
156      (*event_callback)(event_stream, "format bytes-per-line='%p'/",
157                        (void*)(intptr_t) app_data->dinfo.bytes_per_line);
158    }
159
160    while (p < end && !app_data->losing) {
161      (*event_callback)(event_stream, "insn", (void*) p);
162
163      /* reset certain state, so we can read it with confidence */
164      app_data->dinfo.insn_info_valid    = 0;
165      app_data->dinfo.branch_delay_insns = 0;
166      app_data->dinfo.data_size          = 0;
167      app_data->dinfo.insn_type          = 0;
168
169      int size = (*app_data->dfn)((bfd_vma) p, &app_data->dinfo);
170
171      if (size > 0)  p += size;
172      else           app_data->losing = true;
173
174      if (!app_data->losing) {
175        const char* insn_close = format_insn_close("/insn", &app_data->dinfo,
176                                                   buf, sizeof(buf));
177        (*event_callback)(event_stream, insn_close, (void*) p);
178
179        if (app_data->do_newline) {
180          /* follow each complete insn by a nice newline */
181          (*printf_callback)(printf_stream, "\n");
182        }
183      }
184    }
185
186    if (app_data->losing) (*event_callback)(event_stream, "/insns", (void*) p);
187    return (void*) p;
188  }
189}
190
191/* take the address of the function, for luck, and also test the typedef: */
192const decode_func_vtype decode_func_virtual_address = &decode_instructions_virtual;
193const decode_func_stype decode_func_address = &decode_instructions;
194
195static const char* format_insn_close(const char* close,
196                                     disassemble_info* dinfo,
197                                     char* buf, size_t bufsize) {
198  if (!dinfo->insn_info_valid)
199    return close;
200  enum dis_insn_type itype = dinfo->insn_type;
201  int dsize = dinfo->data_size, delays = dinfo->branch_delay_insns;
202  if ((itype == dis_nonbranch && (dsize | delays) == 0)
203      || (strlen(close) + 3*20 > bufsize))
204    return close;
205
206  const char* type = "unknown";
207  switch (itype) {
208  case dis_nonbranch:   type = NULL;         break;
209  case dis_branch:      type = "branch";     break;
210  case dis_condbranch:  type = "condbranch"; break;
211  case dis_jsr:         type = "jsr";        break;
212  case dis_condjsr:     type = "condjsr";    break;
213  case dis_dref:        type = "dref";       break;
214  case dis_dref2:       type = "dref2";      break;
215  }
216
217  strcpy(buf, close);
218  char* p = buf;
219  if (type)    sprintf(p += strlen(p), " type='%s'", type);
220  if (dsize)   sprintf(p += strlen(p), " dsize='%d'", dsize);
221  if (delays)  sprintf(p += strlen(p), " delay='%d'", delays);
222  return buf;
223}
224
225/* handler functions */
226
227static int
228hsdis_read_memory_func(bfd_vma memaddr,
229                       bfd_byte* myaddr,
230                       unsigned int length,
231                       struct disassemble_info* dinfo) {
232  DECL_APP_DATA(dinfo);
233  /* convert the virtual address memaddr into an address within memory buffer */
234  uintptr_t offset = ((uintptr_t) memaddr) - app_data->start_va;
235  if (offset + length > app_data->length) {
236    /* read is out of bounds */
237    return EIO;
238  } else {
239    memcpy(myaddr, (bfd_byte*) (app_data->buffer + offset), length);
240    return 0;
241  }
242}
243
244static void
245hsdis_print_address_func(bfd_vma vma, struct disassemble_info* dinfo) {
246  /* the actual value to print: */
247  void* addr_value = (void*) (uintptr_t) vma;
248  DECL_APP_DATA(dinfo);
249  DECL_EVENT_CALLBACK(app_data);
250
251  /* issue the event: */
252  void* result =
253    (*event_callback)(event_stream, "addr/", addr_value);
254  if (result == NULL) {
255    /* event declined */
256    generic_print_address(vma, dinfo);
257  }
258}
259
260
261/* configuration */
262
263static void set_optional_callbacks(struct hsdis_app_data* app_data);
264static void parse_caller_options(struct hsdis_app_data* app_data,
265                                 const char* caller_options);
266static const char* native_arch_name();
267static enum bfd_endian native_endian();
268static const bfd_arch_info_type* find_arch_info(const char* arch_nane);
269static bfd* get_native_bfd(const bfd_arch_info_type* arch_info,
270                           /* to avoid malloc: */
271                           bfd* empty_bfd, bfd_target* empty_xvec);
272static void init_disassemble_info_from_bfd(struct disassemble_info* dinfo,
273                                           void *stream,
274                                           fprintf_ftype fprintf_func,
275                                           bfd* bfd,
276                                           char* disassembler_options);
277static void parse_fake_insn(disassembler_ftype dfn,
278                            struct disassemble_info* dinfo);
279
280static void setup_app_data(struct hsdis_app_data* app_data,
281                           const char* caller_options) {
282  /* Make reasonable defaults for null callbacks.
283     A non-null stream for a null callback is assumed to be a FILE* for output.
284     Events are rendered as XML.
285  */
286  set_optional_callbacks(app_data);
287
288  /* Look into caller_options for anything interesting. */
289  if (caller_options != NULL)
290    parse_caller_options(app_data, caller_options);
291
292  /* Discover which architecture we are going to disassemble. */
293  app_data->arch_name = &app_data->mach_option[0];
294  if (app_data->arch_name[0] == '\0')
295    app_data->arch_name = native_arch_name();
296  app_data->arch_info = find_arch_info(app_data->arch_name);
297
298  /* Make a fake bfd to hold the arch. and byteorder info. */
299  struct {
300    bfd_target empty_xvec;
301    bfd        empty_bfd;
302  } buf;
303  bfd* native_bfd = get_native_bfd(app_data->arch_info,
304                                   /* to avoid malloc: */
305                                   &buf.empty_bfd, &buf.empty_xvec);
306  init_disassemble_info_from_bfd(&app_data->dinfo,
307                                 app_data->printf_stream,
308                                 app_data->printf_callback,
309                                 native_bfd,
310                                 /* On PowerPC we get warnings, if we pass empty options */
311                                 (caller_options == NULL) ? NULL : app_data->insn_options);
312
313  /* Finish linking together the various callback blocks. */
314  app_data->dinfo.application_data = (void*) app_data;
315  app_data->dfn = disassembler(native_bfd);
316  app_data->dinfo.print_address_func = hsdis_print_address_func;
317  app_data->dinfo.read_memory_func = hsdis_read_memory_func;
318
319  if (app_data->dfn == NULL) {
320    const char* bad = app_data->arch_name;
321    static bool complained;
322    if (bad == &app_data->mach_option[0])
323      print_help(app_data, "bad mach=%s", bad);
324    else if (!complained)
325      print_help(app_data, "bad native mach=%s; please port hsdis to this platform", bad);
326    complained = true;
327    /* must bail out */
328    app_data->losing = true;
329    return;
330  }
331
332  parse_fake_insn(app_data->dfn, &app_data->dinfo);
333}
334
335
336/* ignore all events, return a null */
337static void* null_event_callback(void* ignore_stream, const char* ignore_event, void* arg) {
338  return NULL;
339}
340
341/* print all events as XML markup */
342static void* xml_event_callback(void* stream, const char* event, void* arg) {
343  FILE* fp = (FILE*) stream;
344#define NS_PFX "dis:"
345  if (event[0] != '/') {
346    /* issue the tag, with or without a formatted argument */
347    fprintf(fp, "<"NS_PFX);
348    fprintf(fp, event, arg);
349    fprintf(fp, ">");
350  } else {
351    ++event;                    /* skip slash */
352    const char* argp = strchr(event, ' ');
353    if (argp == NULL) {
354      /* no arguments; just issue the closing tag */
355      fprintf(fp, "</"NS_PFX"%s>", event);
356    } else {
357      /* split out the closing attributes as <dis:foo_done attr='val'/> */
358      int event_prefix = (argp - event);
359      fprintf(fp, "<"NS_PFX"%.*s_done", event_prefix, event);
360      fprintf(fp, argp, arg);
361      fprintf(fp, "/></"NS_PFX"%.*s>", event_prefix, event);
362    }
363  }
364  return NULL;
365}
366
367static void set_optional_callbacks(struct hsdis_app_data* app_data) {
368  if (app_data->printf_callback == NULL) {
369    int (*fprintf_callback)(FILE*, const char*, ...) = &fprintf;
370    FILE* fprintf_stream = stdout;
371    app_data->printf_callback = (printf_callback_t) fprintf_callback;
372    if (app_data->printf_stream == NULL)
373      app_data->printf_stream   = (void*)           fprintf_stream;
374  }
375  if (app_data->event_callback == NULL) {
376    if (app_data->event_stream == NULL)
377      app_data->event_callback = &null_event_callback;
378    else
379      app_data->event_callback = &xml_event_callback;
380  }
381
382}
383
384static void parse_caller_options(struct hsdis_app_data* app_data, const char* caller_options) {
385  char* iop_base = app_data->insn_options;
386  char* iop_limit = iop_base + sizeof(app_data->insn_options) - 1;
387  char* iop = iop_base;
388  const char* p;
389  for (p = caller_options; p != NULL; ) {
390    const char* q = strchr(p, ',');
391    size_t plen = (q == NULL) ? strlen(p) : ((q++) - p);
392    if (plen == 4 && strncmp(p, "help", plen) == 0) {
393      print_help(app_data, NULL, NULL);
394    } else if (plen >= 5 && strncmp(p, "mach=", 5) == 0) {
395      char*  mach_option = app_data->mach_option;
396      size_t mach_size   = sizeof(app_data->mach_option);
397      mach_size -= 1;           /*leave room for the null*/
398      if (plen > mach_size)  plen = mach_size;
399      strncpy(mach_option, p, plen);
400      mach_option[plen] = '\0';
401    } else if (plen > 6 && strncmp(p, "hsdis-", 6) == 0) {
402      // do not pass these to the next level
403    } else {
404      /* just copy it; {i386,sparc}-dis.c might like to see it  */
405      if (iop > iop_base && iop < iop_limit)  (*iop++) = ',';
406      if (iop + plen > iop_limit)
407        plen = iop_limit - iop;
408      strncpy(iop, p, plen);
409      iop += plen;
410    }
411    p = q;
412  }
413}
414
415static void print_help(struct hsdis_app_data* app_data,
416                       const char* msg, const char* arg) {
417  DECL_PRINTF_CALLBACK(app_data);
418  if (msg != NULL) {
419    (*printf_callback)(printf_stream, "hsdis: ");
420    (*printf_callback)(printf_stream, msg, arg);
421    (*printf_callback)(printf_stream, "\n");
422  }
423  (*printf_callback)(printf_stream, "hsdis output options:\n");
424  if (printf_callback == (printf_callback_t) &fprintf)
425    disassembler_usage((FILE*) printf_stream);
426  else
427    disassembler_usage(stderr); /* better than nothing */
428  (*printf_callback)(printf_stream, "  mach=<arch>   select disassembly mode\n");
429#if defined(LIBARCH_i386) || defined(LIBARCH_amd64)
430  (*printf_callback)(printf_stream, "  mach=i386     select 32-bit mode\n");
431  (*printf_callback)(printf_stream, "  mach=x86-64   select 64-bit mode\n");
432  (*printf_callback)(printf_stream, "  suffix        always print instruction suffix\n");
433#endif
434  (*printf_callback)(printf_stream, "  help          print this message\n");
435}
436
437
438/* low-level bfd and arch stuff that binutils doesn't do for us */
439
440static const bfd_arch_info_type* find_arch_info(const char* arch_name) {
441  const bfd_arch_info_type* arch_info = bfd_scan_arch(arch_name);
442  if (arch_info == NULL) {
443    extern const bfd_arch_info_type bfd_default_arch_struct;
444    arch_info = &bfd_default_arch_struct;
445  }
446  return arch_info;
447}
448
449static const char* native_arch_name() {
450  const char* res = NULL;
451#ifdef LIBARCH_i386
452  res = "i386";
453#endif
454#ifdef LIBARCH_amd64
455  res = "i386:x86-64";
456#endif
457#ifdef LIBARCH_sparc
458  res = "sparc:v8plusb";
459#endif
460#ifdef LIBARCH_sparcv9
461  res = "sparc:v9b";
462#endif
463#ifdef LIBARCH_ppc64
464  res = "powerpc:common64";
465#endif
466  if (res == NULL)
467    res = "architecture not set in Makefile!";
468  return res;
469}
470
471static enum bfd_endian native_endian() {
472  int32_t endian_test = 'x';
473  if (*(const char*) &endian_test == 'x')
474    return BFD_ENDIAN_LITTLE;
475  else
476    return BFD_ENDIAN_BIG;
477}
478
479static bfd* get_native_bfd(const bfd_arch_info_type* arch_info,
480                           bfd* empty_bfd, bfd_target* empty_xvec) {
481  memset(empty_bfd,  0, sizeof(*empty_bfd));
482  memset(empty_xvec, 0, sizeof(*empty_xvec));
483  empty_xvec->flavour = bfd_target_unknown_flavour;
484  empty_xvec->byteorder = native_endian();
485  empty_bfd->xvec = empty_xvec;
486  empty_bfd->arch_info = arch_info;
487  return empty_bfd;
488}
489
490static int read_zero_data_only(bfd_vma ignore_p,
491                               bfd_byte* myaddr, unsigned int length,
492                               struct disassemble_info *ignore_info) {
493  memset(myaddr, 0, length);
494  return 0;
495}
496static int print_to_dev_null(void* ignore_stream, const char* ignore_format, ...) {
497  return 0;
498}
499
500/* Prime the pump by running the selected disassembler on a null input.
501   This forces the machine-specific disassembler to divulge invariant
502   information like bytes_per_line.
503 */
504static void parse_fake_insn(disassembler_ftype dfn,
505                            struct disassemble_info* dinfo) {
506  typedef int (*read_memory_ftype)
507    (bfd_vma memaddr, bfd_byte *myaddr, unsigned int length,
508     struct disassemble_info *info);
509  read_memory_ftype read_memory_func = dinfo->read_memory_func;
510  fprintf_ftype     fprintf_func     = dinfo->fprintf_func;
511
512  dinfo->read_memory_func = &read_zero_data_only;
513  dinfo->fprintf_func     = &print_to_dev_null;
514  (*dfn)(0, dinfo);
515
516  /* put it back */
517  dinfo->read_memory_func = read_memory_func;
518  dinfo->fprintf_func     = fprintf_func;
519}
520
521static void init_disassemble_info_from_bfd(struct disassemble_info* dinfo,
522                                           void *stream,
523                                           fprintf_ftype fprintf_func,
524                                           bfd* abfd,
525                                           char* disassembler_options) {
526  init_disassemble_info(dinfo, stream, fprintf_func);
527
528  dinfo->flavour = bfd_get_flavour(abfd);
529  dinfo->arch = bfd_get_arch(abfd);
530  dinfo->mach = bfd_get_mach(abfd);
531  dinfo->disassembler_options = disassembler_options;
532  dinfo->octets_per_byte = bfd_octets_per_byte (abfd);
533  dinfo->skip_zeroes = sizeof(void*) * 2;
534  dinfo->skip_zeroes_at_end = sizeof(void*)-1;
535  dinfo->disassembler_needs_relocs = FALSE;
536
537  if (bfd_big_endian(abfd))
538    dinfo->display_endian = dinfo->endian = BFD_ENDIAN_BIG;
539  else if (bfd_little_endian(abfd))
540    dinfo->display_endian = dinfo->endian = BFD_ENDIAN_LITTLE;
541  else
542    dinfo->endian = native_endian();
543
544  disassemble_init_for_target(dinfo);
545}
546