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main.c
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main.c
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#include <unistd.h>
#include "emu.h"
struct inprec {
uint64_t ir_insn;
size_t ir_len;
char ir_inp[0];
};
uint16_t pc_start,
instr_size;
uint8_t pageprot[0x100];
uint16_t registers[16];
uint8_t memory[0x10000];
#if SYMBOLIC
struct sexp *register_symbols[16];
GHashTable *memory_symbols; // addr -> sexp*
#endif
uint64_t start;
uint64_t insns;
uint64_t insnlimit;
uint64_t insnreplaylim;
uint16_t syminplen;
bool off;
bool unlocked;
bool dep_enabled;
bool replay_mode;
bool ctrlc;
bool tracehex;
FILE *tracefile;
GHashTable *input_record; // insns -> inprec
static bool diverged;
#if SYMBOLIC
static struct sexp SEXP_0 = {.s_kind = S_IMMEDIATE, .s_nargs = 0},
SEXP_1 = {.s_kind = S_IMMEDIATE, .s_nargs = 1},
SEXP_8 = {.s_kind = S_IMMEDIATE, .s_nargs = 8},
SEXP_FF00 = {.s_kind = S_IMMEDIATE, .s_nargs = 0xff00},
SEXP_00FF = {.s_kind = S_IMMEDIATE, .s_nargs = 0x00ff},
SEXP_NEG_1 = {.s_kind = S_IMMEDIATE, .s_nargs = 0xffff};
#endif
// Fast random numbers:
// 18:16 < rmmh> int k = 0x123456; int rand() { k=30903*(k&65535)+(k>>16);
// return(k&65535); }
#if SYMBOLIC
static struct sexp *
bytemask(struct sexp *s)
{
struct sexp *t = sexp_alloc(S_AND);
t->s_nargs = 2;
t->s_arg[0] = s;
t->s_arg[1] = sexp_imm_alloc(0xff);
return t;
}
struct sexp *
mksexp(enum sexp_kind sk, unsigned nargs, ...)
{
struct sexp *t = sexp_alloc(sk);
va_list ap;
ASSERT(nargs <= SEXP_MAXARGS, "xx");
ASSERT(sk != S_INP && sk != S_IMMEDIATE, "xx");
t->s_nargs = nargs;
va_start(ap, nargs);
for (unsigned i = 0; i < nargs; i++) {
struct sexp *a = va_arg(ap, struct sexp *);
ASSERT((uintptr_t)a > 0x10000, "non-null, non-number");
t->s_arg[i] = a;
}
va_end(ap);
return t;
}
#endif
void
print_ips(void)
{
uint64_t end = now();
if (end == start)
end++;
printf("Approx. %ju instructions per second (Total: %ju).\n",
(uintmax_t)insns * 1000000 / (end - start), (uintmax_t)insns);
}
void
init(void)
{
insns = 0;
off = unlocked = false;
start = now();
//memset(memory, 0, sizeof(memory));
memset(registers, 0, sizeof registers);
memset(pageprot, DEP_R|DEP_W|DEP_X, sizeof pageprot);
dep_enabled = false;
#if SYMBOLIC
memory_symbols = g_hash_table_new(NULL, NULL);
ASSERT(memory_symbols, "g_hash");
for (unsigned reg = 0; reg < 16; reg++)
register_symbols[reg] = NULL;
#endif
}
void
destroy(void)
{
#if SYMBOLIC
ASSERT(memory_symbols, "mem_symbol_hash");
g_hash_table_destroy(memory_symbols);
memory_symbols = NULL;
for (unsigned reg = 0; reg < 16; reg++) {
if (isregsym(reg))
free(regsym(reg));
register_symbols[reg] = NULL;
}
#endif
}
#ifndef EMU_CHECK
static void
ctrlc_handler(int s)
{
(void)s;
ctrlc = true;
}
void
usage(void)
{
#if SYMBOLIC
printf("usage: msp430-sym [binaryimage] [sym-inp-len]\n");
#else
printf("usage: msp430-emu FLAGS [binaryimage]\n"
"\n"
" FLAGS:\n"
" -g Debug with GDB\n"
" -t=TRACEFILE Emit instruction trace\n"
" -x Trace output in hex\n");
#endif
exit(1);
}
int
main(int argc, char **argv)
{
size_t rd, idx;
const char *romfname;
FILE *romfile;
int opt;
bool waitgdb = false;
#if SYMBOLIC
if (argc < 3)
#else
if (argc < 2)
#endif
usage();
#if SYMBOLIC
romfname = argv[1];
#else
while ((opt = getopt(argc, argv, "gt:x")) != -1) {
switch (opt) {
case 'g':
waitgdb = true;
break;
case 't':
tracefile = fopen(optarg, "wb");
if (!tracefile) {
printf("Failed to open tracefile `%s'\n",
optarg);
exit(1);
}
break;
case 'x':
tracehex = true;
break;
default:
usage();
break;
}
}
if (optind >= argc)
usage();
romfname = argv[optind];
#endif
romfile = fopen(romfname, "rb");
ASSERT(romfile, "fopen");
#if SYMBOLIC
syminplen = atoll(argv[2]);
#endif
input_record = g_hash_table_new_full(NULL, NULL, NULL, free);
ASSERT(input_record, "x");
init();
idx = 0;
while (true) {
rd = fread(&memory[idx], 1, sizeof(memory) - idx, romfile);
if (rd == 0)
break;
idx += rd;
}
printf("Loaded %zu words from image.\n", idx/2);
memwriteword(0x10, 0x4130); // callgate
fclose(romfile);
signal(SIGINT, ctrlc_handler);
registers[PC] = memword(0xfffe);
if (waitgdb)
gdbstub_init();
emulate();
printf("Got CPUOFF, stopped.\n");
gdbstub_stopped();
print_regs();
print_ips();
if (tracefile)
fclose(tracefile);
return 0;
}
#endif
#if SYMBOLIC
static bool
sexpdepth(struct sexp *s, unsigned max)
{
if (max == 0)
return true;
if (s->s_kind == S_INP || s->s_kind == S_IMMEDIATE)
return false;
for (unsigned i = 0; i < s->s_nargs; i++)
if (sexpdepth(s->s_arg[i], max - 1))
return true;
return false;
}
#endif
void
emulate1(void)
{
uint16_t instr;
pc_start = registers[PC];
instr_size = 2;
#ifdef BF
if (registers[PC] & 0x1) {
//printf("insn addr unaligned");
off = true;
return;
}
#else
ASSERT((registers[PC] & 0x1) == 0, "insn addr unaligned");
#endif
depcheck(registers[PC], DEP_X);
instr = memword(registers[PC]);
// dec r15; jnz -2 busy loop
if ((instr == 0x831f || instr == 0x533f) &&
memword(registers[PC]+2) == 0x23fe) {
#if SYMBOLIC
ASSERT(!isregsym(15), "TODO");
#endif
//insns += (2ul * registers[15]) + 1;
registers[15] = 0;
#if SYMBOLIC
ASSERT(!isregsym(SR), "TODO");
#endif
registers[SR] &= ~(SR_C | SR_N | SR_V);
registers[SR] |= SR_Z;
registers[PC] += 4;
goto out;
}
switch (bits(instr, 15, 13)) {
case 0:
handle_single(instr);
break;
case 0x2000:
handle_jump(instr);
break;
default:
handle_double(instr);
break;
}
#if SYMBOLIC
for (unsigned i = 0; i < 16; i++) {
if (!isregsym(i))
continue;
// concretify
if (regsym(i)->s_kind == S_IMMEDIATE) {
registers[i] = regsym(i)->s_nargs;
register_symbols[i] = NULL;
continue;
}
// depth=12 -> only uses first 6 bytes
// depth=11 -> only uses first 4?
#if 0
if (sexpdepth(regsym(i), 7)) {
printf("r%d is *too* symbolic:\n", i);
printsym(regsym(i));
printf("/r%d\n", i);
print_regs();
off = true;
}
#endif
}
#endif
if (!replay_mode && tracefile) {
ASSERT((instr_size / 2) > 0 && (instr_size / 2) < 4,
"instr_size: %d", instr_size);
for (unsigned i = 0; i < instr_size; i += 2) {
if (tracehex)
fprintf(tracefile, "%02x%02x ",
(uns)membyte(pc_start+i),
(uns)membyte(pc_start+i+1));
else {
size_t wr;
wr = fwrite(&memory[(pc_start + i) & 0xffff],
2, 1, tracefile);
ASSERT(wr == 1, "fwrite: %s", strerror(errno));
}
}
if (tracehex)
fprintf(tracefile, "\n");
}
out:
insns++;
}
static void
dumpmem(uint16_t addr, unsigned len)
{
for (unsigned i = 0; i < len; i++) {
printf("%02x", membyte(addr+i));
if (i % 0x10 == 0xf)
printf("\n");
}
}
void
emulate(void)
{
#ifndef QUIET
printf("Initial register state:\n");
print_regs();
printf("============================================\n\n");
#endif
while (true) {
if (ctrlc) {
printf("Got ^C, stopping...\n");
abort_nodump();
}
#if SYMBOLIC
if (isregsym(PC)) {
printf("symbolic PC\n");
abort_nodump();
}
#endif
#ifndef EMU_CHECK
if (replay_mode && insns >= insnreplaylim) {
replay_mode = false;
insnreplaylim = 0;
// return control to remote GDB
stepone = true;
}
if (!replay_mode)
gdbstub_intr();
if (replay_mode && insnreplaylim < insns) {
init();
registers[PC] = memword(0xfffe);
continue;
}
#endif
if (registers[PC] == 0x0010) {
#if SYMBOLIC
if (isregsym(SR)) {
printf("Symbolic interrupt!!!\nSR =>");
printsym(regsym(SR));
abort_nodump();
}
#endif
// Callgate
if (registers[SR] & 0x8000) {
unsigned op = (registers[SR] >> 8) & 0x7f;
callgate(op);
}
}
if (off)
break;
emulate1();
#if SYMBOLIC
ASSERT(!isregsym(CG), "CG symbolic");
#endif
ASSERT(registers[CG] == 0, "CG");
if (off || registers[SR] & SR_CPUOFF) {
off = true;
break;
}
if (insnlimit && insns >= insnlimit) {
#ifndef BF
printf("\nXXX Hit insn limit, halting XXX\n");
#endif
break;
}
}
}
void
inc_reg(uint16_t reg, uint16_t bw)
{
uint16_t inc = 2;
if (reg != PC && reg != SP && bw)
inc = 1;
#if SYMBOLIC
ASSERT(!isregsym(reg), "symbolic reg(%u): can't inc", (uns)reg);
#endif
registers[reg] = (registers[reg] + inc) & 0xffff;
}
void
dec_reg(uint16_t reg, uint16_t bw)
{
uint16_t inc = 2;
if (reg != PC && reg != SP && bw)
inc = 1;
#if SYMBOLIC
ASSERT(!isregsym(reg), "symbolic reg(%u): can't dec", (uns)reg);
#endif
registers[reg] = (registers[reg] - inc) & 0xffff;
}
void
handle_jump(uint16_t instr)
{
uint16_t cnd = bits(instr, 12, 10) >> 10,
offset = bits(instr, 9, 0);
bool shouldjump = false;
// sign-extend
if (offset & 0x200)
offset |= 0xfc00;
// double
offset = (offset << 1) & 0xffff;
inc_reg(PC, 0);
#if SYMBOLIC
if (cnd != 0x7 && isregsym(SR)) {
printf("XXX symbolic branch\nSR: ");
printsym(regsym(SR));
abort_nodump();
}
#endif
switch (cnd) {
case 0x0:
// JNZ
if ((registers[SR] & SR_Z) == 0)
shouldjump = true;
break;
case 0x1:
// JZ
if (registers[SR] & SR_Z)
shouldjump = true;
break;
case 0x2:
// JNC
if ((registers[SR] & SR_C) == 0)
shouldjump = true;
break;
case 0x3:
// JC
if (registers[SR] & SR_C)
shouldjump = true;
break;
case 0x4:
// JN
if (registers[SR] & SR_N)
shouldjump = true;
break;
case 0x5:
// JGE
{
bool N = !!(registers[SR] & SR_N),
V = !!(registers[SR] & SR_V);
shouldjump = ((N ^ V) == 0);
}
break;
case 0x6:
// JL
{
bool N = !!(registers[SR] & SR_N),
V = !!(registers[SR] & SR_V);
shouldjump = (N ^ V);
}
break;
case 0x7:
// JMP
shouldjump = true;
break;
default:
unhandled(instr);
break;
}
if (shouldjump)
registers[PC] = (registers[PC] + offset) & 0xffff;
}
void
handle_single(uint16_t instr)
{
enum operand_kind srckind, dstkind;
uint16_t constbits = bits(instr, 12, 10) >> 10,
bw = bits(instr, 6, 6),
As = bits(instr, 5, 4),
dsrc = bits(instr, 3, 0),
srcval, srcnum = 0, dstval;
unsigned res = (uns)-1;
uint16_t setflags = 0,
clrflags = 0;
#if SYMBOLIC
struct sexp *srcsym = NULL, *ressym = NULL, *flagsym = NULL;
#endif
inc_reg(PC, 0);
// Bogus initialization for GCC
srcval = 0xffff;
srckind = OP_FLAGSONLY;
load_src(instr, dsrc, As, bw, &srcval, &srckind);
if (off)
return;
dstkind = srckind;
dstval = srcval;
// Load addressed src values
switch (srckind) {
case OP_REG:
#if SYMBOLIC
if (isregsym(srcval))
srcsym = regsym(srcval);
else
#endif
srcnum = registers[srcval];
break;
case OP_MEM:
#if SYMBOLIC
if (ismemsym(srcval, bw))
srcsym = memsym(srcval, bw);
else {
#endif
if (bw)
srcnum = membyte(srcval);
else
srcnum = memword(srcval);
#if SYMBOLIC
}
#endif
break;
case OP_CONST:
srcnum = srcval;
break;
default:
ASSERT(false, "illins");
break;
}
// '0x0000' is an illegal instruction, but #uctf ignores bits 0x1800 in
// single-op instructions. We'll do it just for zero, trap on
// everything else...
if (constbits != 0x4 && instr != 0x0 && instr != 0x03)
illins(instr);
switch (bits(instr, 9, 7)) {
case 0x000:
// RRC
#if SYMBOLIC
if (srcsym) {
if (bw)
srcsym = peephole(bytemask(srcsym));
ressym = mksexp(S_RSHIFT, 2, srcsym, &SEXP_1);
flagsym = mksexp(S_SR_RRC, 1, peephole(ressym));
} else {
#endif
if (bw)
srcnum &= 0xff;
res = srcnum >> 1;
#if SYMBOLIC
ASSERT(!isregsym(SR), "TODO");
#endif
if (registers[SR] & SR_C) {
if (bw)
res |= 0x80;
else
res |= 0x8000;
}
if (srcnum & 0x1)
setflags |= SR_C;
else
clrflags |= SR_C;
if (res & 0x8000)
setflags |= SR_N;
// doesn't clear N
if (res)
clrflags |= SR_Z;
// doesn't set Z
#if SYMBOLIC
}
#endif
break;
case 0x080:
// SWPB (no flags)
#if SYMBOLIC
if (srcsym) {
struct sexp *lo, *hi;
hi = mksexp(S_LSHIFT, 2, bytemask(srcsym), &SEXP_8);
lo = mksexp(S_RSHIFT, 2, srcsym, &SEXP_8);
ressym = mksexp(S_OR, 2, hi, lo);
} else
#endif
res = ((srcnum & 0xff) << 8) | (srcnum >> 8);
break;
case 0x100:
// RRA (flags)
#if SYMBOLIC
if (srcsym) {
if (bw)
srcsym = peephole(bytemask(srcsym));
ressym = mksexp(S_RRA, 2, srcsym, &SEXP_1);
flagsym = mksexp(S_SR_RRA, 1, ressym);
} else {
#endif
if (bw)
srcnum &= 0xff;
res = srcnum >> 1;
if (bw && (0x80 & srcnum))
res |= 0x80;
else if (bw == 0 && (0x8000 & srcnum))
res |= 0x8000;
clrflags |= SR_Z;
if (0x8000 & res)
setflags |= SR_N;
#if SYMBOLIC
}
#endif
break;
case 0x180:
// SXT (sets flags)
#if SYMBOLIC
if (srcsym) {
ressym = mksexp(S_SXT, 1, peephole(mksexp(S_AND, 2,
srcsym, &SEXP_00FF)));
flagsym = mksexp(S_SR_AND, 1, ressym);
} else {
#endif
if (srcnum & 0x80)
res = srcnum | 0xff00;
else
res = srcnum & 0x00ff;
andflags(res, &setflags, &clrflags);
#if SYMBOLIC
}
#endif
break;
case 0x200:
// PUSH (no flags)
dec_reg(SP, 0);
dstval = registers[SP];
dstkind = OP_MEM;
#if SYMBOLIC
if (srcsym)
ressym = srcsym;
else
#endif
res = srcnum;
break;
case 0x280:
// CALL (no flags)
#if SYMBOLIC
if (srcsym) {
printf("XXX symbolic CALL\n");
abort_nodump();
} else {
#endif
// Call [src]
res = srcnum;
dstval = PC;
dstkind = OP_REG;
// Push PC+1
dec_reg(SP, 0);
memwriteword(registers[SP], registers[PC]);
#if SYMBOLIC
}
#endif
break;
default:
unhandled(instr);
break;
}
#if SYMBOLIC
// concretify
if (ressym && ressym->s_kind == S_IMMEDIATE) {
res = ressym->s_nargs & 0xffff;
sexp_flags(flagsym, &setflags, &clrflags);
ressym = NULL;
}
if (ressym) {
if (flagsym)
register_symbols[SR] = peephole(flagsym);
if (dstkind == OP_REG)
register_symbols[dstval] = peephole(ressym);
else if (dstkind == OP_MEM)
memwritesym(dstval, bw, peephole(ressym));
else
ASSERT(dstkind == OP_FLAGSONLY, "x");
} else {
#endif
if (setflags || clrflags) {
ASSERT((setflags & clrflags) == 0, "set/clr flags shouldn't overlap");
#if SYMBOLIC
if (isregsym(SR)) {
struct sexp *s = sexp_alloc(S_OR), *t;
s->s_nargs = 2;
s->s_arg[0] = regsym(SR);
s->s_arg[1] = sexp_imm_alloc(setflags);
t = sexp_alloc(S_AND);
t->s_nargs = 2;
t->s_arg[0] = s;
t->s_arg[1] = sexp_imm_alloc(~clrflags & 0x1ff);
register_symbols[SR] = peephole(t);
} else {
#endif
registers[SR] |= setflags;
registers[SR] &= ~clrflags;
registers[SR] &= 0x1ff;
#if SYMBOLIC
}
#endif
}
if (dstkind == OP_REG) {
ASSERT(res != (uns)-1, "res never set");
if (bw)
res &= 0x00ff;
#if SYMBOLIC
if (isregsym(dstval))
register_symbols[dstval] = NULL;
#endif
if (dstval != CG)
registers[dstval] = res & 0xffff;
} else if (dstkind == OP_MEM) {
#if SYMBOLIC
if (ismemsym(dstval, bw))
delmemsyms(dstval, bw);
#endif
depcheck(dstval, DEP_W);
if (bw)
memory[dstval] = (res & 0xff);
else
memwriteword(dstval, res);
} else if (dstkind == OP_CONST) {
ASSERT(instr == 0x3, "instr: %04x", instr);
} else
ASSERT(dstkind == OP_FLAGSONLY, "x: %u", dstkind);
#if SYMBOLIC
}
#endif
}
void
handle_double(uint16_t instr)
{
enum operand_kind srckind, dstkind;
uint16_t dsrc = bits(instr, 11, 8) >> 8,
Ad = bits(instr, 7, 7),
bw = bits(instr, 6, 6),
As = bits(instr, 5, 4),
ddst = bits(instr, 3, 0);
uint16_t srcval /*absolute addr or register number or constant*/,
dstval /*absolute addr or register number*/;
unsigned res = (unsigned)-1,
dstnum = 0, srcnum = 0 /*as a number*/;
uint16_t setflags = 0,
clrflags = 0;
#if SYMBOLIC
struct sexp *srcsym = NULL, *ressym = NULL, *dstsym = NULL,
*flagsym = NULL;
#endif
inc_reg(PC, 0);
// Bogus initialization to quiet GCC
srckind = OP_FLAGSONLY;
srcval = 0xffff;
load_src(instr, dsrc, As, bw, &srcval, &srckind);
load_dst(instr, ddst, Ad, &dstval, &dstkind);
if (off)
return;
// Load addressed src values
switch (srckind) {
case OP_REG:
#if SYMBOLIC
if (isregsym(srcval))
srcsym = regsym(srcval);
else
#endif
srcnum = registers[srcval];
break;
case OP_MEM:
#if SYMBOLIC
if (ismemsym(srcval, bw))
srcsym = memsym(srcval, bw);
else {
#endif
if (bw)
srcnum = membyte(srcval);
else
srcnum = memword(srcval);
#if SYMBOLIC
}
#endif
break;
case OP_CONST:
srcnum = srcval;
break;
default:
ASSERT(false, "illins");
break;
}
// Load addressed dst values
switch (dstkind) {
case OP_REG:
#if SYMBOLIC
if (isregsym(dstval))
dstsym = regsym(dstval);
else
#endif
dstnum = registers[dstval];
break;
case OP_MEM:
#if SYMBOLIC
if (ismemsym(dstval, bw))
dstsym = memsym(dstval, bw);
else {
#endif
if (bw)
dstnum = membyte(dstval);
else
dstnum = memword(dstval);
#if SYMBOLIC
}
#endif
break;
case OP_CONST:
ASSERT(instr == 0x4303 || instr == 0x03, "nop");
return;
default:
ASSERT(false, "illins");
break;
}
#if SYMBOLIC
// If either input is symbolic, both are. Put the other value in a
// temporary symbol.
if (srcsym && dstsym == NULL) {
dstsym = sexp_imm_alloc(dstnum);
} else if (dstsym && srcsym == NULL) {
srcsym = sexp_imm_alloc(srcnum);
}
#endif
switch (bits(instr, 15, 12)) {
case 0x4000:
// MOV (no flags)
#if SYMBOLIC
if (srcsym)
ressym = srcsym;
else
#endif
res = srcnum;
break;
case 0x5000:
// ADD (flags)
#if SYMBOLIC
if (srcsym) {
if (bw) {
srcsym = peephole(bytemask(srcsym));
dstsym = peephole(bytemask(dstsym));
}
ressym = peephole(mksexp(S_PLUS, 2, srcsym, dstsym));
flagsym = mksexp(S_AND, 2, mksexp(S_SR, 1, ressym), &SEXP_00FF);
} else {
#endif
if (bw) {
dstnum &= 0xff;
srcnum &= 0xff;
}
res = dstnum + srcnum;
addflags(res, bw, &setflags, &clrflags);
if (bw)
res &= 0x00ff;
else
res &= 0xffff;
#if SYMBOLIC
}
#endif
break;
case 0x6000:
// ADDC (flags)
#if SYMBOLIC
if (srcsym) {
printf("XXX symbolic ADDC ->SR\n");
abort_nodump();
} else {