diff options
Diffstat (limited to 'arch/x86/tools/insn_decoder_test.c')
| -rw-r--r-- | arch/x86/tools/insn_decoder_test.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/arch/x86/tools/insn_decoder_test.c b/arch/x86/tools/insn_decoder_test.c new file mode 100644 index 000000000..34eda63c1 --- /dev/null +++ b/arch/x86/tools/insn_decoder_test.c @@ -0,0 +1,172 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * + * 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_buff[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_buff, 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_buff[nb++] = (unsigned char) b; + s += 3; + } else + break; + } + /* Decode an instruction */ + insn_init(&insn, insn_buff, sizeof(insn_buff), 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; +} |