arch/x86/tools/test_get_len.c

   1 /*
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License as published by
   4  * the Free Software Foundation; either version 2 of the License, or
   5  * (at your option) any later version.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  *
  12  * You should have received a copy of the GNU General Public License
  13  * along with this program; if not, write to the Free Software
  14  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  15  *
  16  * Copyright (C) IBM Corporation, 2009
  17  */
  18
  19 #include <stdlib.h>
  20 #include <stdio.h>
  21 #include <string.h>
  22 #include <assert.h>
  23 #include <unistd.h>
  24
  25 #define unlikely(cond) (cond)
  26
  27 #include <asm/insn.h>
  28 #include <inat.c>
  29 #include <insn.c>
  30
  31 /*
  32  * Test of instruction analysis in general and insn_get_length() in
  33  * particular.  See if insn_get_length() and the disassembler agree
  34  * on the length of each instruction in an elf disassembly.
  35  *
  36  * Usage: objdump -d a.out | awk -f distill.awk | ./test_get_len
  37  */
  38
  39 const char *prog;
  40 static int verbose;
  41 static int x86_64;
  42
  43 static void usage(void)
  44 {
  45         fprintf(stderr, "Usage: objdump -d a.out | awk -f distill.awk |"
  46                 " %s [-y|-n] [-v]\n", prog);
  47         fprintf(stderr, "\t-y   64bit mode\n");
  48         fprintf(stderr, "\t-n   32bit mode\n");
  49         fprintf(stderr, "\t-v   verbose mode\n");
  50         exit(1);
  51 }
  52
  53 static void malformed_line(const char *line, int line_nr)
  54 {
  55         fprintf(stderr, "%s: malformed line %d:\n%s", prog, line_nr, line);
  56         exit(3);
  57 }
  58
  59 static void dump_field(FILE *fp, const char *name, const char *indent,
  60                        struct insn_field *field)
  61 {
  62         fprintf(fp, "%s.%s = {\n", indent, name);
  63         fprintf(fp, "%s\t.value = %d, bytes[] = {%x, %x, %x, %x},\n",
  64                 indent, field->value, field->bytes[0], field->bytes[1],
  65                 field->bytes[2], field->bytes[3]);
  66         fprintf(fp, "%s\t.got = %d, .nbytes = %d},\n", indent,
  67                 field->got, field->nbytes);
  68 }
  69
  70 static void dump_insn(FILE *fp, struct insn *insn)
  71 {
  72         fprintf(fp, "Instruction = {\n");
  73         dump_field(fp, "prefixes", "\t",        &insn->prefixes);
  74         dump_field(fp, "rex_prefix", "\t",      &insn->rex_prefix);
  75         dump_field(fp, "vex_prefix", "\t",      &insn->vex_prefix);
  76         dump_field(fp, "opcode", "\t",          &insn->opcode);
  77         dump_field(fp, "modrm", "\t",           &insn->modrm);
  78         dump_field(fp, "sib", "\t",             &insn->sib);
  79         dump_field(fp, "displacement", "\t",    &insn->displacement);
  80         dump_field(fp, "immediate1", "\t",      &insn->immediate1);
  81         dump_field(fp, "immediate2", "\t",      &insn->immediate2);
  82         fprintf(fp, "\t.attr = %x, .opnd_bytes = %d, .addr_bytes = %d,\n",
  83                 insn->attr, insn->opnd_bytes, insn->addr_bytes);
  84         fprintf(fp, "\t.length = %d, .x86_64 = %d, .kaddr = %p}\n",
  85                 insn->length, insn->x86_64, insn->kaddr);
  86 }
  87
  88 static void parse_args(int argc, char **argv)
  89 {
  90         int c;
  91         prog = argv[0];
  92         while ((c = getopt(argc, argv, "ynv")) != -1) {
  93                 switch (c) {
  94                 case 'y':
  95                         x86_64 = 1;
  96                         break;
  97                 case 'n':
  98                         x86_64 = 0;
  99                         break;
 100                 case 'v':
 101                         verbose = 1;
 102                         break;
 103                 default:
 104                         usage();
 105                 }
 106         }
 107 }
 108
 109 #define BUFSIZE 256
 110
 111 int main(int argc, char **argv)
 112 {
 113         char line[BUFSIZE], sym[BUFSIZE] = "<unknown>";
 114         unsigned char insn_buf[16];
 115         struct insn insn;
 116         int insns = 0;
 117         int warnings = 0;
 118
 119         parse_args(argc, argv);
 120
 121         while (fgets(line, BUFSIZE, stdin)) {
 122                 char copy[BUFSIZE], *s, *tab1, *tab2;
 123                 int nb = 0;
 124                 unsigned int b;
 125
 126                 if (line[0] == '<') {
 127                         /* Symbol line */
 128                         strcpy(sym, line);
 129                         continue;
 130                 }
 131
 132                 insns++;
 133                 memset(insn_buf, 0, 16);
 134                 strcpy(copy, line);
 135                 tab1 = strchr(copy, '\t');
 136                 if (!tab1)
 137                         malformed_line(line, insns);
 138                 s = tab1 + 1;
 139                 s += strspn(s, " ");
 140                 tab2 = strchr(s, '\t');
 141                 if (!tab2)
 142                         malformed_line(line, insns);
 143                 *tab2 = '\0';   /* Characters beyond tab2 aren't examined */
 144                 while (s < tab2) {
 145                         if (sscanf(s, "%x", &b) == 1) {
 146                                 insn_buf[nb++] = (unsigned char) b;
 147                                 s += 3;
 148                         } else
 149                                 break;
 150                 }
 151                 /* Decode an instruction */
 152                 insn_init(&insn, insn_buf, sizeof(insn_buf), x86_64);
 153                 insn_get_length(&insn);
 154                 if (insn.length != nb) {
 155                         warnings++;
 156                         fprintf(stderr, "Warning: %s found difference at %s\n",
 157                                 prog, sym);
 158                         fprintf(stderr, "Warning: %s", line);
 159                         fprintf(stderr, "Warning: objdump says %d bytes, but "
 160                                 "insn_get_length() says %d\n", nb,
 161                                 insn.length);
 162                         if (verbose)
 163                                 dump_insn(stderr, &insn);
 164                 }
 165         }
 166         if (warnings)
 167                 fprintf(stderr, "Warning: decoded and checked %d"
 168                         " instructions with %d warnings\n", insns, warnings);
 169         else
 170                 fprintf(stdout, "Success: decoded and checked %d"
 171                         " instructions\n", insns);
 172         return 0;
 173 }