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 * Copyright (C) IBM Corporation, 2009 13 */ 14 15 #include <stdlib.h> 16 #include <stdio.h> 17 #include <string.h> 18 #include <assert.h> 19 #include <unistd.h> 20 #include <stdarg.h> 21 22 #define unlikely(cond) (cond) 23 24 #include <asm/insn.h> 25 #include <inat.c> 26 #include <insn.c> 27 28 /* 29 * Test of instruction analysis in general and insn_get_length() in 30 * particular. See if insn_get_length() and the disassembler agree 31 * on the length of each instruction in an elf disassembly. 32 * 33 * Usage: objdump -d a.out | awk -f objdump_reformat.awk | ./insn_decoder_test 34 */ 35 36 const char *prog; 37 static int verbose; 38 static int x86_64; 39 40 static void usage(void) 41 { 42 fprintf(stderr, "Usage: objdump -d a.out | awk -f objdump_reformat.awk" 43 " | %s [-y|-n] [-v]\n", prog); 44 fprintf(stderr, "\t-y 64bit mode\n"); 45 fprintf(stderr, "\t-n 32bit mode\n"); 46 fprintf(stderr, "\t-v verbose mode\n"); 47 exit(1); 48 } 49 50 static void malformed_line(const char *line, int line_nr) 51 { 52 fprintf(stderr, "%s: error: malformed line %d:\n%s", 53 prog, line_nr, line); 54 exit(3); 55 } 56 57 static void pr_warn(const char *fmt, ...) 58 { 59 va_list ap; 60 61 fprintf(stderr, "%s: warning: ", prog); 62 va_start(ap, fmt); 63 vfprintf(stderr, fmt, ap); 64 va_end(ap); 65 } 66 67 static void dump_field(FILE *fp, const char *name, const char *indent, 68 struct insn_field *field) 69 { 70 fprintf(fp, "%s.%s = {\n", indent, name); 71 fprintf(fp, "%s\t.value = %d, bytes[] = {%x, %x, %x, %x},\n", 72 indent, field->value, field->bytes[0], field->bytes[1], 73 field->bytes[2], field->bytes[3]); 74 fprintf(fp, "%s\t.got = %d, .nbytes = %d},\n", indent, 75 field->got, field->nbytes); 76 } 77 78 static void dump_insn(FILE *fp, struct insn *insn) 79 { 80 fprintf(fp, "Instruction = {\n"); 81 dump_field(fp, "prefixes", "\t", &insn->prefixes); 82 dump_field(fp, "rex_prefix", "\t", &insn->rex_prefix); 83 dump_field(fp, "vex_prefix", "\t", &insn->vex_prefix); 84 dump_field(fp, "opcode", "\t", &insn->opcode); 85 dump_field(fp, "modrm", "\t", &insn->modrm); 86 dump_field(fp, "sib", "\t", &insn->sib); 87 dump_field(fp, "displacement", "\t", &insn->displacement); 88 dump_field(fp, "immediate1", "\t", &insn->immediate1); 89 dump_field(fp, "immediate2", "\t", &insn->immediate2); 90 fprintf(fp, "\t.attr = %x, .opnd_bytes = %d, .addr_bytes = %d,\n", 91 insn->attr, insn->opnd_bytes, insn->addr_bytes); 92 fprintf(fp, "\t.length = %d, .x86_64 = %d, .kaddr = %p}\n", 93 insn->length, insn->x86_64, insn->kaddr); 94 } 95 96 static void parse_args(int argc, char **argv) 97 { 98 int c; 99 prog = argv[0]; 100 while ((c = getopt(argc, argv, "ynv")) != -1) { 101 switch (c) { 102 case 'y': 103 x86_64 = 1; 104 break; 105 case 'n': 106 x86_64 = 0; 107 break; 108 case 'v': 109 verbose = 1; 110 break; 111 default: 112 usage(); 113 } 114 } 115 } 116 117 #define BUFSIZE 256 118 119 int main(int argc, char **argv) 120 { 121 char line[BUFSIZE], sym[BUFSIZE] = "<unknown>"; 122 unsigned char insn_buf[16]; 123 struct insn insn; 124 int insns = 0; 125 int warnings = 0; 126 127 parse_args(argc, argv); 128 129 while (fgets(line, BUFSIZE, stdin)) { 130 char copy[BUFSIZE], *s, *tab1, *tab2; 131 int nb = 0; 132 unsigned int b; 133 134 if (line[0] == '<') { 135 /* Symbol line */ 136 strcpy(sym, line); 137 continue; 138 } 139 140 insns++; 141 memset(insn_buf, 0, 16); 142 strcpy(copy, line); 143 tab1 = strchr(copy, '\t'); 144 if (!tab1) 145 malformed_line(line, insns); 146 s = tab1 + 1; 147 s += strspn(s, " "); 148 tab2 = strchr(s, '\t'); 149 if (!tab2) 150 malformed_line(line, insns); 151 *tab2 = '\0'; /* Characters beyond tab2 aren't examined */ 152 while (s < tab2) { 153 if (sscanf(s, "%x", &b) == 1) { 154 insn_buf[nb++] = (unsigned char) b; 155 s += 3; 156 } else 157 break; 158 } 159 /* Decode an instruction */ 160 insn_init(&insn, insn_buf, sizeof(insn_buf), x86_64); 161 insn_get_length(&insn); 162 if (insn.length != nb) { 163 warnings++; 164 pr_warn("Found an x86 instruction decoder bug, " 165 "please report this.\n", sym); 166 pr_warn("%s", line); 167 pr_warn("objdump says %d bytes, but insn_get_length() " 168 "says %d\n", nb, insn.length); 169 if (verbose) 170 dump_insn(stderr, &insn); 171 } 172 } 173 if (warnings) 174 pr_warn("Decoded and checked %d instructions with %d " 175 "failures\n", insns, warnings); 176 else 177 fprintf(stdout, "%s: success: Decoded and checked %d" 178 " instructions\n", prog, insns); 179 return 0; 180 } 181