1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * 4 * Copyright (C) IBM Corporation, 2009 5 */ 6 7 #include <stdlib.h> 8 #include <stdio.h> 9 #include <string.h> 10 #include <assert.h> 11 #include <unistd.h> 12 #include <stdarg.h> 13 14 #define unlikely(cond) (cond) 15 16 #include <asm/insn.h> 17 #include <inat.c> 18 #include <insn.c> 19 20 /* 21 * Test of instruction analysis in general and insn_get_length() in 22 * particular. See if insn_get_length() and the disassembler agree 23 * on the length of each instruction in an elf disassembly. 24 * 25 * Usage: objdump -d a.out | awk -f objdump_reformat.awk | ./insn_decoder_test 26 */ 27 28 const char *prog; 29 static int verbose; 30 static int x86_64; 31 32 static void usage(void) 33 { 34 fprintf(stderr, "Usage: objdump -d a.out | awk -f objdump_reformat.awk" 35 " | %s [-y|-n] [-v]\n", prog); 36 fprintf(stderr, "\t-y 64bit mode\n"); 37 fprintf(stderr, "\t-n 32bit mode\n"); 38 fprintf(stderr, "\t-v verbose mode\n"); 39 exit(1); 40 } 41 42 static void malformed_line(const char *line, int line_nr) 43 { 44 fprintf(stderr, "%s: error: malformed line %d:\n%s", 45 prog, line_nr, line); 46 exit(3); 47 } 48 49 static void pr_warn(const char *fmt, ...) 50 { 51 va_list ap; 52 53 fprintf(stderr, "%s: warning: ", prog); 54 va_start(ap, fmt); 55 vfprintf(stderr, fmt, ap); 56 va_end(ap); 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_buff[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_buff, 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_buff[nb++] = (unsigned char) b; 147 s += 3; 148 } else 149 break; 150 } 151 /* Decode an instruction */ 152 insn_init(&insn, insn_buff, sizeof(insn_buff), x86_64); 153 insn_get_length(&insn); 154 if (insn.length != nb) { 155 warnings++; 156 pr_warn("Found an x86 instruction decoder bug, " 157 "please report this.\n", sym); 158 pr_warn("%s", line); 159 pr_warn("objdump says %d bytes, but insn_get_length() " 160 "says %d\n", nb, insn.length); 161 if (verbose) 162 dump_insn(stderr, &insn); 163 } 164 } 165 if (warnings) 166 pr_warn("Decoded and checked %d instructions with %d " 167 "failures\n", insns, warnings); 168 else 169 fprintf(stdout, "%s: success: Decoded and checked %d" 170 " instructions\n", prog, insns); 171 return 0; 172 } 173