/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 1998-2011. All Rights Reserved.
*
* The contents of this file are subject to the Erlang Public License,
* Version 1.1, (the "License"); you may not use this file except in
* compliance with the License. You should have received a copy of the
* Erlang Public License along with this software. If not, it can be
* retrieved online at http://www.erlang.org/.
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
* the License for the specific language governing rights and limitations
* under the License.
*
* %CopyrightEnd%
*/
/*
* Purpose: Basic debugging support.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "sys.h"
#include "erl_vm.h"
#include "global.h"
#include "erl_process.h"
#include "error.h"
#include "erl_driver.h"
#include "bif.h"
#include "big.h"
#include "external.h"
#include "beam_load.h"
#include "beam_bp.h"
#include "erl_binary.h"
#include "erl_thr_progress.h"
#ifdef ARCH_64
# define HEXF "%016bpX"
#else
# define HEXF "%08bpX"
#endif
#define TermWords(t) (((t) / (sizeof(BeamInstr)/sizeof(Eterm))) + !!((t) % (sizeof(BeamInstr)/sizeof(Eterm))))
void dbg_bt(Process* p, Eterm* sp);
void dbg_where(BeamInstr* addr, Eterm x0, Eterm* reg);
static int print_op(int to, void *to_arg, int op, int size, BeamInstr* addr);
BIF_RETTYPE
erts_debug_same_2(BIF_ALIST_2)
{
return (BIF_ARG_1 == BIF_ARG_2) ? am_true : am_false;
}
BIF_RETTYPE
erts_debug_flat_size_1(BIF_ALIST_1)
{
Process* p = BIF_P;
Eterm term = BIF_ARG_1;
Uint size = size_object(term);
if (IS_USMALL(0, size)) {
BIF_RET(make_small(size));
} else {
Eterm* hp = HAlloc(p, BIG_UINT_HEAP_SIZE);
BIF_RET(uint_to_big(size, hp));
}
}
BIF_RETTYPE
erts_debug_breakpoint_2(BIF_ALIST_2)
{
Process* p = BIF_P;
Eterm MFA = BIF_ARG_1;
Eterm bool = BIF_ARG_2;
Eterm* tp;
Eterm mfa[3];
int i;
int specified = 0;
Eterm res;
if (bool != am_true && bool != am_false)
goto error;
if (is_not_tuple(MFA)) {
goto error;
}
tp = tuple_val(MFA);
if (*tp != make_arityval(3)) {
goto error;
}
mfa[0] = tp[1];
mfa[1] = tp[2];
mfa[2] = tp[3];
if (!is_atom(mfa[0]) || !is_atom(mfa[1]) ||
(!is_small(mfa[2]) && mfa[2] != am_Underscore)) {
goto error;
}
for (i = 0; i < 3 && mfa[i] != am_Underscore; i++, specified++) {
/* Empty loop body */
}
for (i = specified; i < 3; i++) {
if (mfa[i] != am_Underscore) {
goto error;
}
}
if (is_small(mfa[2])) {
mfa[2] = signed_val(mfa[2]);
}
erts_smp_proc_unlock(p, ERTS_PROC_LOCK_MAIN);
erts_smp_thr_progress_block();
if (bool == am_true) {
res = make_small(erts_set_debug_break(mfa, specified));
} else {
res = make_small(erts_clear_debug_break(mfa, specified));
}
erts_smp_thr_progress_unblock();
erts_smp_proc_lock(p, ERTS_PROC_LOCK_MAIN);
return res;
error:
BIF_ERROR(p, BADARG);
}
#if 0 /* Kept for conveninence when hard debugging. */
void debug_dump_code(BeamInstr *I, int num)
{
BeamInstr *code_ptr = I;
BeamInstr *end = code_ptr + num;
erts_dsprintf_buf_t *dsbufp;
BeamInstr instr;
int i;
dsbufp = erts_create_tmp_dsbuf(0);
while (code_ptr < end) {
erts_print(ERTS_PRINT_DSBUF, (void *) dsbufp, HEXF ": ", code_ptr);
instr = (BeamInstr) code_ptr[0];
for (i = 0; i < NUM_SPECIFIC_OPS; i++) {
if (instr == (BeamInstr) BeamOp(i) && opc[i].name[0] != '\0') {
code_ptr += print_op(ERTS_PRINT_DSBUF, (void *) dsbufp,
i, opc[i].sz-1, code_ptr+1) + 1;
break;
}
}
if (i >= NUM_SPECIFIC_OPS) {
erts_print(ERTS_PRINT_DSBUF, (void *) dsbufp,
"unknown " HEXF "\n", instr);
code_ptr++;
}
}
dsbufp->str[dsbufp->str_len] = 0;
erts_fprintf(stderr,"%s", dsbufp->str);
erts_destroy_tmp_dsbuf(dsbufp);
}
#endif
BIF_RETTYPE
erts_debug_instructions_0(BIF_ALIST_0)
{
int i = 0;
Uint needed = num_instructions * 2;
Eterm* hp;
Eterm res = NIL;
for (i = 0; i < num_instructions; i++) {
needed += 2*strlen(opc[i].name);
}
hp = HAlloc(BIF_P, needed);
for (i = num_instructions-1; i >= 0; i--) {
Eterm s = erts_bld_string_n(&hp, 0, opc[i].name, strlen(opc[i].name));
res = erts_bld_cons(&hp, 0, s, res);
}
return res;
}
BIF_RETTYPE
erts_debug_disassemble_1(BIF_ALIST_1)
{
Process* p = BIF_P;
Eterm addr = BIF_ARG_1;
erts_dsprintf_buf_t *dsbufp;
Eterm* hp;
Eterm* tp;
Eterm bin;
Eterm mfa;
BeamInstr* funcinfo = NULL; /* Initialized to eliminate warning. */
BeamInstr* code_base;
BeamInstr* code_ptr = NULL; /* Initialized to eliminate warning. */
BeamInstr instr;
BeamInstr uaddr;
Uint hsz;
int i;
if (term_to_UWord(addr, &uaddr)) {
code_ptr = (BeamInstr *) uaddr;
if ((funcinfo = find_function_from_pc(code_ptr)) == NULL) {
BIF_RET(am_false);
}
} else if (is_tuple(addr)) {
ErtsCodeIndex code_ix;
Module* modp;
Eterm mod;
Eterm name;
Export* ep;
Sint arity;
int n;
tp = tuple_val(addr);
if (tp[0] != make_arityval(3)) {
error:
BIF_ERROR(p, BADARG);
}
mod = tp[1];
name = tp[2];
if (!is_atom(mod) || !is_atom(name) || !is_small(tp[3])) {
goto error;
}
arity = signed_val(tp[3]);
modp = erts_get_module(mod);
/*
* Try the export entry first to allow disassembly of special functions
* such as erts_debug:apply/4. Then search for it in the module.
*/
code_ix = erts_active_code_ix();
if ((ep = erts_find_function(mod, name, arity, code_ix)) != NULL) {
/* XXX: add "&& ep->address != ep->code+3" condition?
* Consider a traced function.
* Its ep will have ep->address == ep->code+3.
* erts_find_function() will return the non-NULL ep.
* Below we'll try to derive a code_ptr from ep->address.
* But this code_ptr will point to the start of the Export,
* not the function's func_info instruction. BOOM !?
*/
code_ptr = ((BeamInstr *) ep->addressv[code_ix]) - 5;
funcinfo = code_ptr+2;
} else if (modp == NULL || (code_base = modp->curr.code) == NULL) {
BIF_RET(am_undef);
} else {
n = code_base[MI_NUM_FUNCTIONS];
for (i = 0; i < n; i++) {
code_ptr = (BeamInstr *) code_base[MI_FUNCTIONS+i];
if (code_ptr[3] == name && code_ptr[4] == arity) {
funcinfo = code_ptr+2;
break;
}
}
if (i == n) {
BIF_RET(am_undef);
}
}
} else {
goto error;
}
dsbufp = erts_create_tmp_dsbuf(0);
erts_print(ERTS_PRINT_DSBUF, (void *) dsbufp, HEXF ": ", code_ptr);
instr = (BeamInstr) code_ptr[0];
for (i = 0; i < NUM_SPECIFIC_OPS; i++) {
if (instr == (BeamInstr) BeamOp(i) && opc[i].name[0] != '\0') {
code_ptr += print_op(ERTS_PRINT_DSBUF, (void *) dsbufp,
i, opc[i].sz-1, code_ptr+1) + 1;
break;
}
}
if (i >= NUM_SPECIFIC_OPS) {
erts_print(ERTS_PRINT_DSBUF, (void *) dsbufp,
"unknown " HEXF "\n", instr);
code_ptr++;
}
bin = new_binary(p, (byte *) dsbufp->str, dsbufp->str_len);
erts_destroy_tmp_dsbuf(dsbufp);
hsz = 4+4;
(void) erts_bld_uword(NULL, &hsz, (BeamInstr) code_ptr);
hp = HAlloc(p, hsz);
addr = erts_bld_uword(&hp, NULL, (BeamInstr) code_ptr);
ASSERT(is_atom(funcinfo[0]));
ASSERT(is_atom(funcinfo[1]));
mfa = TUPLE3(hp, (Eterm) funcinfo[0], (Eterm) funcinfo[1], make_small((Eterm) funcinfo[2]));
hp += 4;
return TUPLE3(hp, addr, bin, mfa);
}
void
dbg_bt(Process* p, Eterm* sp)
{
Eterm* stack = STACK_START(p);
while (sp < stack) {
if (is_CP(*sp)) {
BeamInstr* addr = find_function_from_pc(cp_val(*sp));
if (addr)
erts_fprintf(stderr,
HEXF ": %T:%T/%bpu\n",
addr, (Eterm) addr[0], (Eterm) addr[1], addr[2]);
}
sp++;
}
}
void
dbg_where(BeamInstr* addr, Eterm x0, Eterm* reg)
{
BeamInstr* f = find_function_from_pc(addr);
if (f == NULL) {
erts_fprintf(stderr, "???\n");
} else {
int arity;
int i;
addr = f;
arity = addr[2];
erts_fprintf(stderr, HEXF ": %T:%T(", addr, (Eterm) addr[0], (Eterm) addr[1]);
for (i = 0; i < arity; i++)
erts_fprintf(stderr, i ? ", %T" : "%T", i ? reg[i] : x0);
erts_fprintf(stderr, ")\n");
}
}
static int
print_op(int to, void *to_arg, int op, int size, BeamInstr* addr)
{
int i;
BeamInstr tag;
char* sign;
char* start_prog; /* Start of program for packer. */
char* prog; /* Current position in packer program. */
BeamInstr stack[8]; /* Stack for packer. */
BeamInstr* sp = stack; /* Points to next free position. */
BeamInstr packed = 0; /* Accumulator for packed operations. */
BeamInstr args[8]; /* Arguments for this instruction. */
BeamInstr* ap; /* Pointer to arguments. */
BeamInstr* unpacked; /* Unpacked arguments */
start_prog = opc[op].pack;
if (start_prog[0] == '\0') {
/*
* There is no pack program.
* Avoid copying because instructions containing bignum operands
* are bigger than actually declared.
*/
ap = (BeamInstr *) addr;
} else {
/*
* Copy all arguments to a local buffer for the unpacking.
*/
ASSERT(size <= sizeof(args)/sizeof(args[0]));
ap = args;
for (i = 0; i < size; i++) {
*ap++ = addr[i];
}
/*
* Undo any packing done by the loader. This is easily done by running
* the packing program backwards and in reverse.
*/
prog = start_prog + strlen(start_prog);
while (start_prog < prog) {
prog--;
switch (*prog) {
case 'g':
*ap++ = *--sp;
break;
case 'i': /* Initialize packing accumulator. */
*ap++ = packed;
break;
case 's':
*ap++ = packed & 0x3ff;
packed >>= 10;
break;
case '0': /* Tight shift */
*ap++ = packed & (BEAM_TIGHT_MASK / sizeof(Eterm));
packed >>= BEAM_TIGHT_SHIFT;
break;
case '6': /* Shift 16 steps */
*ap++ = packed & BEAM_LOOSE_MASK;
packed >>= BEAM_LOOSE_SHIFT;
break;
#ifdef ARCH_64
case 'w': /* Shift 32 steps */
*ap++ = packed & BEAM_WIDE_MASK;
packed >>= BEAM_WIDE_SHIFT;
break;
#endif
case 'p':
*sp++ = *--ap;
break;
case 'P':
packed = *--sp;
break;
default:
ASSERT(0);
}
}
ap = args;
}
/*
* Print the name and all operands of the instructions.
*/
erts_print(to, to_arg, "%s ", opc[op].name);
sign = opc[op].sign;
while (*sign) {
switch (*sign) {
case 'r': /* x(0) */
erts_print(to, to_arg, "x(0)");
break;
case 'x': /* x(N) */
if (reg_index(ap[0]) == 0) {
erts_print(to, to_arg, "x[0]");
} else {
erts_print(to, to_arg, "x(%d)", reg_index(ap[0]));
}
ap++;
break;
case 'y': /* y(N) */
erts_print(to, to_arg, "y(%d)", reg_index(ap[0]) - CP_SIZE);
ap++;
break;
case 'n': /* Nil */
erts_print(to, to_arg, "[]");
break;
case 's': /* Any source (tagged constant or register) */
tag = beam_reg_tag(*ap);
if (tag == X_REG_DEF) {
if (reg_index(*ap) == 0) {
erts_print(to, to_arg, "x[0]");
} else {
erts_print(to, to_arg, "x(%d)", reg_index(*ap));
}
ap++;
break;
} else if (tag == Y_REG_DEF) {
erts_print(to, to_arg, "y(%d)", reg_index(*ap) - CP_SIZE);
ap++;
break;
} else if (tag == R_REG_DEF) {
erts_print(to, to_arg, "x(0)");
ap++;
break;
}
/*FALLTHROUGH*/
case 'a': /* Tagged atom */
case 'i': /* Tagged integer */
case 'c': /* Tagged constant */
case 'q': /* Tagged literal */
erts_print(to, to_arg, "%T", (Eterm) *ap);
ap++;
break;
case 'A':
erts_print(to, to_arg, "%d", arityval( (Eterm) ap[0]));
ap++;
break;
case 'd': /* Destination (x(0), x(N), y(N)) */
switch (beam_reg_tag(*ap)) {
case X_REG_DEF:
if (reg_index(*ap) == 0) {
erts_print(to, to_arg, "x[0]");
} else {
erts_print(to, to_arg, "x(%d)", reg_index(*ap));
}
break;
case Y_REG_DEF:
erts_print(to, to_arg, "y(%d)", reg_index(*ap) - CP_SIZE);
break;
case R_REG_DEF:
erts_print(to, to_arg, "x(0)");
break;
}
ap++;
break;
case 'I': /* Untagged integer. */
case 't':
erts_print(to, to_arg, "%d", *ap);
ap++;
break;
case 'f': /* Destination label */
{
BeamInstr* f = find_function_from_pc((BeamInstr *)*ap);
if (f+3 != (BeamInstr *) *ap) {
erts_print(to, to_arg, "f(" HEXF ")", *ap);
} else {
erts_print(to, to_arg, "%T:%T/%bpu", (Eterm) f[0], (Eterm) f[1], f[2]);
}
ap++;
}
break;
case 'p': /* Pointer (to label) */
{
BeamInstr* f = find_function_from_pc((BeamInstr *)*ap);
if (f+3 != (BeamInstr *) *ap) {
erts_print(to, to_arg, "p(" HEXF ")", *ap);
} else {
erts_print(to, to_arg, "%T:%T/%bpu", (Eterm) f[0], (Eterm) f[1], f[2]);
}
ap++;
}
break;
case 'j': /* Pointer (to label) */
erts_print(to, to_arg, "j(" HEXF ")", *ap);
ap++;
break;
case 'e': /* Export entry */
{
Export* ex = (Export *) *ap;
erts_print(to, to_arg,
"%T:%T/%bpu", (Eterm) ex->code[0], (Eterm) ex->code[1], ex->code[2]);
ap++;
}
break;
case 'F': /* Function definition */
break;
case 'b':
for (i = 0; i < BIF_SIZE; i++) {
BifFunction bif = (BifFunction) *ap;
if (bif == bif_table[i].f) {
break;
}
}
if (i == BIF_SIZE) {
erts_print(to, to_arg, "b(%d)", (Uint) *ap);
} else {
Eterm name = bif_table[i].name;
unsigned arity = bif_table[i].arity;
erts_print(to, to_arg, "%T/%u", name, arity);
}
ap++;
break;
case 'P': /* Byte offset into tuple (see beam_load.c) */
case 'Q': /* Like 'P', but packable */
erts_print(to, to_arg, "%d", (*ap / sizeof(Eterm)) - 1);
ap++;
break;
case 'l': /* fr(N) */
erts_print(to, to_arg, "fr(%d)", reg_index(ap[0]));
ap++;
break;
default:
erts_print(to, to_arg, "???");
ap++;
break;
}
erts_print(to, to_arg, " ");
sign++;
}
/*
* Print more information about certain instructions.
*/
unpacked = ap;
ap = addr + size;
switch (op) {
case op_i_select_val_rfI:
case op_i_select_val_xfI:
case op_i_select_val_yfI:
{
int n = ap[-1];
while (n > 0) {
erts_print(to, to_arg, "%T f(" HEXF ") ", (Eterm) ap[0], ap[1]);
ap += 2;
size += 2;
n--;
}
}
break;
case op_i_select_tuple_arity_rfI:
case op_i_select_tuple_arity_xfI:
case op_i_select_tuple_arity_yfI:
{
int n = ap[-1];
while (n > 0) {
Uint arity = arityval(ap[0]);
erts_print(to, to_arg, " {%d} f(" HEXF ")", arity, ap[1]);
ap += 2;
size += 2;
n--;
}
}
break;
case op_i_jump_on_val_rfII:
case op_i_jump_on_val_xfII:
case op_i_jump_on_val_yfII:
{
int n;
for (n = ap[-2]; n > 0; n--) {
erts_print(to, to_arg, "f(" HEXF ") ", ap[0]);
ap++;
size++;
}
}
break;
case op_i_jump_on_val_zero_rfI:
case op_i_jump_on_val_zero_xfI:
case op_i_jump_on_val_zero_yfI:
{
int n;
for (n = ap[-1]; n > 0; n--) {
erts_print(to, to_arg, "f(" HEXF ") ", ap[0]);
ap++;
size++;
}
}
break;
case op_i_put_tuple_rI:
case op_i_put_tuple_xI:
case op_i_put_tuple_yI:
{
int n = unpacked[-1];
while (n > 0) {
if (!is_header(ap[0])) {
erts_print(to, to_arg, " %T", (Eterm) ap[0]);
} else {
switch ((ap[0] >> 2) & 0x03) {
case R_REG_DEF:
erts_print(to, to_arg, " x(0)");
break;
case X_REG_DEF:
erts_print(to, to_arg, " x(%d)", ap[0] >> 4);
break;
case Y_REG_DEF:
erts_print(to, to_arg, " y(%d)", ap[0] >> 4);
break;
}
}
ap++, size++, n--;
}
}
break;
}
erts_print(to, to_arg, "\n");
return size;
}