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/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* Copyright (C) IBM Corporation, 2009
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <unistd.h>
#include <stdarg.h>
#define unlikely(cond) (cond)
#include <asm/insn.h>
#include <inat.c>
#include <insn.c>
/*
* Test of instruction analysis in general and insn_get_length() in
* particular. See if insn_get_length() and the disassembler agree
* on the length of each instruction in an elf disassembly.
*
* Usage: objdump -d a.out | awk -f objdump_reformat.awk | ./insn_decoder_test
*/
const char *prog;
static int verbose;
static int x86_64;
static void usage(void)
{
fprintf(stderr, "Usage: objdump -d a.out | awk -f objdump_reformat.awk"
" | %s [-y|-n] [-v]\n", prog);
fprintf(stderr, "\t-y 64bit mode\n");
fprintf(stderr, "\t-n 32bit mode\n");
fprintf(stderr, "\t-v verbose mode\n");
exit(1);
}
static void malformed_line(const char *line, int line_nr)
{
fprintf(stderr, "%s: error: malformed line %d:\n%s",
prog, line_nr, line);
exit(3);
}
static void pr_warn(const char *fmt, ...)
{
va_list ap;
fprintf(stderr, "%s: warning: ", prog);
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
}
static void dump_field(FILE *fp, const char *name, const char *indent,
struct insn_field *field)
{
fprintf(fp, "%s.%s = {\n", indent, name);
fprintf(fp, "%s\t.value = %d, bytes[] = {%x, %x, %x, %x},\n",
indent, field->value, field->bytes[0], field->bytes[1],
field->bytes[2], field->bytes[3]);
fprintf(fp, "%s\t.got = %d, .nbytes = %d},\n", indent,
field->got, field->nbytes);
}
static void dump_insn(FILE *fp, struct insn *insn)
{
fprintf(fp, "Instruction = {\n");
dump_field(fp, "prefixes", "\t", &insn->prefixes);
dump_field(fp, "rex_prefix", "\t", &insn->rex_prefix);
dump_field(fp, "vex_prefix", "\t", &insn->vex_prefix);
dump_field(fp, "opcode", "\t", &insn->opcode);
dump_field(fp, "modrm", "\t", &insn->modrm);
dump_field(fp, "sib", "\t", &insn->sib);
dump_field(fp, "displacement", "\t", &insn->displacement);
dump_field(fp, "immediate1", "\t", &insn->immediate1);
dump_field(fp, "immediate2", "\t", &insn->immediate2);
fprintf(fp, "\t.attr = %x, .opnd_bytes = %d, .addr_bytes = %d,\n",
insn->attr, insn->opnd_bytes, insn->addr_bytes);
fprintf(fp, "\t.length = %d, .x86_64 = %d, .kaddr = %p}\n",
insn->length, insn->x86_64, insn->kaddr);
}
static void parse_args(int argc, char **argv)
{
int c;
prog = argv[0];
while ((c = getopt(argc, argv, "ynv")) != -1) {
switch (c) {
case 'y':
x86_64 = 1;
break;
case 'n':
x86_64 = 0;
break;
case 'v':
verbose = 1;
break;
default:
usage();
}
}
}
#define BUFSIZE 256
int main(int argc, char **argv)
{
char line[BUFSIZE], sym[BUFSIZE] = "<unknown>";
unsigned char insn_buf[16];
struct insn insn;
int insns = 0;
int warnings = 0;
parse_args(argc, argv);
while (fgets(line, BUFSIZE, stdin)) {
char copy[BUFSIZE], *s, *tab1, *tab2;
int nb = 0;
unsigned int b;
if (line[0] == '<') {
/* Symbol line */
strcpy(sym, line);
continue;
}
insns++;
memset(insn_buf, 0, 16);
strcpy(copy, line);
tab1 = strchr(copy, '\t');
if (!tab1)
malformed_line(line, insns);
s = tab1 + 1;
s += strspn(s, " ");
tab2 = strchr(s, '\t');
if (!tab2)
malformed_line(line, insns);
*tab2 = '\0'; /* Characters beyond tab2 aren't examined */
while (s < tab2) {
if (sscanf(s, "%x", &b) == 1) {
insn_buf[nb++] = (unsigned char) b;
s += 3;
} else
break;
}
/* Decode an instruction */
insn_init(&insn, insn_buf, sizeof(insn_buf), x86_64);
insn_get_length(&insn);
if (insn.length != nb) {
warnings++;
pr_warn("Found an x86 instruction decoder bug, "
"please report this.\n", sym);
pr_warn("%s", line);
pr_warn("objdump says %d bytes, but insn_get_length() "
"says %d\n", nb, insn.length);
if (verbose)
dump_insn(stderr, &insn);
}
}
if (warnings)
pr_warn("Decoded and checked %d instructions with %d "
"failures\n", insns, warnings);
else
fprintf(stdout, "%s: success: Decoded and checked %d"
" instructions\n", prog, insns);
return 0;
}
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