Implemented jump-to breakpoints

This commit is contained in:
Lior Halphon 2019-04-12 20:29:43 +03:00
parent 19f42d5a3a
commit 05cd81b77c
3 changed files with 311 additions and 11 deletions

View File

@ -34,6 +34,7 @@ struct GB_breakpoint_s {
uint32_t key; /* For sorting and comparing */
};
char *condition;
bool is_jump_to;
};
#define BP_KEY(x) (((struct GB_breakpoint_s){.addr = ((x).value), .bank = (x).has_bank? (x).bank : -1 }).key)
@ -845,7 +846,15 @@ static uint16_t find_breakpoint(GB_gameboy_t *gb, value_t addr)
static bool breakpoint(GB_gameboy_t *gb, char *arguments, char *modifiers, const debugger_command_t *command)
{
NO_MODIFIERS
bool is_jump_to = true;
if (!modifiers) {
is_jump_to = false;
}
else if (strcmp(modifiers, "j") != 0) {
print_usage(gb, command);
return true;
}
if (strlen(lstrip(arguments)) == 0) {
print_usage(gb, command);
return true;
@ -904,6 +913,12 @@ static bool breakpoint(GB_gameboy_t *gb, char *arguments, char *modifiers, const
gb->breakpoints[index].condition = NULL;
}
gb->n_breakpoints++;
gb->breakpoints[index].is_jump_to = is_jump_to;
if (is_jump_to) {
gb->has_jump_to_breakpoints = true;
}
GB_log(gb, "Breakpoint set at %s\n", debugger_value_to_string(gb, result, true));
return true;
@ -955,6 +970,16 @@ static bool delete(GB_gameboy_t *gb, char *arguments, char *modifiers, const deb
free(gb->breakpoints[index].condition);
}
if (gb->breakpoints[index].is_jump_to) {
gb->has_jump_to_breakpoints = false;
for (unsigned i = 0; i < gb->n_breakpoints; i++) {
if (i == index) continue;
if (gb->breakpoints[i].is_jump_to) {
gb->has_jump_to_breakpoints = true;
break;
}
}
}
memmove(&gb->breakpoints[index], &gb->breakpoints[index + 1], (gb->n_breakpoints - index - 1) * sizeof(gb->breakpoints[0]));
gb->n_breakpoints--;
@ -1152,12 +1177,15 @@ static bool list(GB_gameboy_t *gb, char *arguments, char *modifiers, const debug
for (uint16_t i = 0; i < gb->n_breakpoints; i++) {
value_t addr = (value_t){gb->breakpoints[i].bank != (uint16_t)-1, gb->breakpoints[i].bank, gb->breakpoints[i].addr};
if (gb->breakpoints[i].condition) {
GB_log(gb, " %d. %s (Condition: %s)\n", i + 1,
GB_log(gb, " %d. %s (%sCondition: %s)\n", i + 1,
debugger_value_to_string(gb, addr, addr.has_bank),
gb->breakpoints[i].is_jump_to? "Jump to, ": "",
gb->breakpoints[i].condition);
}
else {
GB_log(gb, " %d. %s\n", i + 1, debugger_value_to_string(gb, addr, addr.has_bank));
GB_log(gb, " %d. %s%s\n", i + 1,
debugger_value_to_string(gb, addr, addr.has_bank),
gb->breakpoints[i].is_jump_to? " (Jump to)" : "");
}
}
}
@ -1186,12 +1214,12 @@ static bool list(GB_gameboy_t *gb, char *arguments, char *modifiers, const debug
return true;
}
static bool _should_break(GB_gameboy_t *gb, value_t addr)
static bool _should_break(GB_gameboy_t *gb, value_t addr, bool jump_to)
{
uint16_t index = find_breakpoint(gb, addr);
uint32_t key = BP_KEY(addr);
if (index < gb->n_breakpoints && gb->breakpoints[index].key == key) {
if (index < gb->n_breakpoints && gb->breakpoints[index].key == key && gb->breakpoints[index].is_jump_to == jump_to) {
if (!gb->breakpoints[index].condition) {
return true;
}
@ -1208,16 +1236,16 @@ static bool _should_break(GB_gameboy_t *gb, value_t addr)
return false;
}
static bool should_break(GB_gameboy_t *gb, uint16_t addr)
static bool should_break(GB_gameboy_t *gb, uint16_t addr, bool jump_to)
{
/* Try any-bank breakpoint */
value_t full_addr = (VALUE_16(addr));
if (_should_break(gb, full_addr)) return true;
if (_should_break(gb, full_addr, jump_to)) return true;
/* Try bank-specific breakpoint */
full_addr.has_bank = true;
full_addr.bank = bank_for_addr(gb, addr);
return _should_break(gb, full_addr);
return _should_break(gb, full_addr, jump_to);
}
static bool print(GB_gameboy_t *gb, char *arguments, char *modifiers, const debugger_command_t *command)
@ -1562,8 +1590,10 @@ static const debugger_command_t commands[] = {
{"lcd", 3, lcd, "Displays information about the current state of the LCD controller"},
{"palettes", 3, palettes, "Displays the current CGB palettes"},
{"breakpoint", 1, breakpoint, "Add a new breakpoint at the specified address/expression" HELP_NEWLINE
"Can also modify the condition of existing breakpoints.",
"<expression>[ if <condition expression>]"},
"Can also modify the condition of existing breakpoints." HELP_NEWLINE
"If the j modifier is used, the breakpoint will occur just" HELP_NEWLINE
"before jumping to the target.",
"<expression>[ if <condition expression>]", "(j)"},
{"delete", 2, delete, "Delete a breakpoint by its address, or all breakpoints", "[<expression>]"},
{"watch", 1, watch, "Add a new watchpoint at the specified address/expression." HELP_NEWLINE
"Can also modify the condition and type of existing watchpoints." HELP_NEWLINE
@ -1834,6 +1864,14 @@ bool GB_debugger_execute_command(GB_gameboy_t *gb, char *input)
}
}
typedef enum {
JUMP_TO_NONE,
JUMP_TO_BREAK,
JUMP_TO_NONTRIVIAL,
} jump_to_return_t;
static jump_to_return_t test_jump_to_breakpoints(GB_gameboy_t *gb, uint16_t *address);
void GB_debugger_run(GB_gameboy_t *gb)
{
if (gb->debug_disable) return;
@ -1852,11 +1890,55 @@ next_command:
if (input) {
free(input);
}
if (gb->breakpoints && !gb->debug_stopped && should_break(gb, gb->pc)) {
if (gb->breakpoints && !gb->debug_stopped && should_break(gb, gb->pc, false)) {
gb->debug_stopped = true;
GB_log(gb, "Breakpoint: PC = %s\n", value_to_string(gb, gb->pc, true));
GB_cpu_disassemble(gb, gb->pc, 5);
}
if (gb->breakpoints && !gb->debug_stopped) {
uint16_t address = 0;
jump_to_return_t jump_to_result = test_jump_to_breakpoints(gb, &address);
bool should_delete_state = true;
if (gb->nontrivial_jump_state && should_break(gb, gb->pc, true)) {
if (gb->non_trivial_jump_breakpoint_occured) {
gb->non_trivial_jump_breakpoint_occured = false;
}
else {
gb->non_trivial_jump_breakpoint_occured = true;
GB_log(gb, "Jumping to breakpoint: PC = %s\n", value_to_string(gb, gb->pc, true));
GB_cpu_disassemble(gb, gb->pc, 5);
GB_load_state_from_buffer(gb, gb->nontrivial_jump_state, -1);
gb->debug_stopped = true;
}
}
else if (jump_to_result == JUMP_TO_BREAK) {
gb->debug_stopped = true;
GB_log(gb, "Jumping to breakpoint: PC = %s\n", value_to_string(gb, address, true));
GB_cpu_disassemble(gb, gb->pc, 5);
gb->non_trivial_jump_breakpoint_occured = false;
}
else if (jump_to_result == JUMP_TO_NONTRIVIAL) {
if (!gb->nontrivial_jump_state) {
gb->nontrivial_jump_state = malloc(GB_get_save_state_size(gb));
}
GB_save_state_to_buffer(gb, gb->nontrivial_jump_state);
gb->non_trivial_jump_breakpoint_occured = false;
should_delete_state = false;
}
else {
gb->non_trivial_jump_breakpoint_occured = false;
}
if (should_delete_state) {
if (gb->nontrivial_jump_state) {
free(gb->nontrivial_jump_state);
gb->nontrivial_jump_state = NULL;
}
}
}
if (gb->debug_stopped && !gb->debug_disable) {
gb->debug_next_command = false;
gb->debug_fin_command = false;
@ -1986,3 +2068,210 @@ void GB_debugger_set_disabled(GB_gameboy_t *gb, bool disabled)
{
gb->debug_disable = disabled;
}
/* Jump-to breakpoints */
static bool is_in_trivial_memory(uint16_t addr)
{
/* ROM */
if (addr < 0x8000) {
return true;
}
/* HRAM */
if (addr >= 0xFF80 && addr < 0xFFFF) {
return true;
}
/* RAM */
if (addr >= 0xC000 && addr < 0xE000) {
return true;
}
return false;
}
typedef uint16_t GB_opcode_address_getter_t(GB_gameboy_t *gb, uint8_t opcode);
uint16_t trivial_1(GB_gameboy_t *gb, uint8_t opcode)
{
return gb->pc + 1;
}
uint16_t trivial_2(GB_gameboy_t *gb, uint8_t opcode)
{
return gb->pc + 2;
}
uint16_t trivial_3(GB_gameboy_t *gb, uint8_t opcode)
{
return gb->pc + 3;
}
static uint16_t jr_r8(GB_gameboy_t *gb, uint8_t opcode)
{
return gb->pc + 2 + (int8_t)GB_read_memory(gb, gb->pc + 1);
}
static bool condition_code(GB_gameboy_t *gb, uint8_t opcode)
{
switch ((opcode >> 3) & 0x3) {
case 0:
return !(gb->registers[GB_REGISTER_AF] & GB_ZERO_FLAG);
case 1:
return (gb->registers[GB_REGISTER_AF] & GB_ZERO_FLAG);
case 2:
return !(gb->registers[GB_REGISTER_AF] & GB_CARRY_FLAG);
case 3:
return (gb->registers[GB_REGISTER_AF] & GB_CARRY_FLAG);
}
return false;
}
static uint16_t jr_cc_r8(GB_gameboy_t *gb, uint8_t opcode)
{
if (!condition_code(gb, opcode)) {
return gb->pc + 2;
}
return gb->pc + 2 + (int8_t)GB_read_memory(gb, gb->pc + 1);
}
static uint16_t ret(GB_gameboy_t *gb, uint8_t opcode)
{
return GB_read_memory(gb, gb->registers[GB_REGISTER_SP]) |
(GB_read_memory(gb, gb->registers[GB_REGISTER_SP] + 1) << 8);
}
static uint16_t ret_cc(GB_gameboy_t *gb, uint8_t opcode)
{
if (condition_code(gb, opcode)) {
return ret(gb, opcode);
}
else {
return gb->pc + 1;
}
}
static uint16_t jp_a16(GB_gameboy_t *gb, uint8_t opcode)
{
return GB_read_memory(gb, gb->pc + 1) |
(GB_read_memory(gb, gb->pc + 2) << 8);
}
static uint16_t jp_cc_a16(GB_gameboy_t *gb, uint8_t opcode)
{
if (condition_code(gb, opcode)) {
return jp_a16(gb, opcode);
}
else {
return gb->pc + 3;
}
}
static uint16_t rst(GB_gameboy_t *gb, uint8_t opcode)
{
return opcode ^ 0xC7;
}
static uint16_t jp_hl(GB_gameboy_t *gb, uint8_t opcode)
{
return gb->hl;
}
static GB_opcode_address_getter_t *opcodes[256] = {
/* X0 X1 X2 X3 X4 X5 X6 X7 */
/* X8 X9 Xa Xb Xc Xd Xe Xf */
trivial_1, trivial_3, trivial_1, trivial_1, trivial_1, trivial_1, trivial_2, trivial_1, /* 0X */
trivial_3, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_2, trivial_1,
trivial_2, trivial_3, trivial_1, trivial_1, trivial_1, trivial_1, trivial_2, trivial_1, /* 1X */
jr_r8, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_2, trivial_1,
jr_cc_r8, trivial_3, trivial_1, trivial_1, trivial_1, trivial_1, trivial_2, trivial_1, /* 2X */
jr_cc_r8, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_2, trivial_1,
jr_cc_r8, trivial_3, trivial_1, trivial_1, trivial_1, trivial_1, trivial_2, trivial_1, /* 3X */
jr_cc_r8, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_2, trivial_1,
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, /* 4X */
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1,
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, /* 5X */
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1,
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, /* 6X */
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1,
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, NULL, trivial_1, /* 7X */
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1,
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, /* 8X */
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1,
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, /* 9X */
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1,
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, /* aX */
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1,
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, /* bX */
trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1, trivial_1,
ret_cc, trivial_1, jp_cc_a16, jp_a16, jp_cc_a16, trivial_1, trivial_2, rst, /* cX */
ret_cc, ret, jp_cc_a16, trivial_2, jp_cc_a16, jp_a16, trivial_2, rst,
ret_cc, trivial_1, jp_cc_a16, NULL, jp_cc_a16, trivial_1, trivial_2, rst, /* dX */
ret_cc, ret, jp_cc_a16, NULL, jp_cc_a16, NULL, trivial_2, rst,
trivial_2, trivial_1, trivial_1, NULL, NULL, trivial_1, trivial_2, rst, /* eX */
trivial_2, jp_hl, trivial_3, NULL, NULL, NULL, trivial_2, rst,
trivial_2, trivial_1, trivial_1, trivial_1, NULL, trivial_1, trivial_2, rst, /* fX */
trivial_2, trivial_1, trivial_3, trivial_1, NULL, NULL, trivial_2, rst,
};
static jump_to_return_t test_jump_to_breakpoints(GB_gameboy_t *gb, uint16_t *address)
{
if (!gb->has_jump_to_breakpoints) return JUMP_TO_NONE;
if (!is_in_trivial_memory(gb->pc) || !is_in_trivial_memory(gb->pc + 2) ||
!is_in_trivial_memory(gb->registers[GB_REGISTER_SP]) || !is_in_trivial_memory(gb->registers[GB_REGISTER_SP] + 1)) {
return JUMP_TO_NONTRIVIAL;
}
/* Interrupts */
if (gb->ime) {
for (unsigned i = 0; i < 5; i++) {
if ((gb->interrupt_enable & (1 << i)) && (gb->io_registers[GB_IO_IF] & (1 << i))) {
if (should_break(gb, 0x40 + i * 8, true)) {
if (address) {
*address = 0x40 + i * 8;
}
return JUMP_TO_BREAK;
}
}
}
}
uint16_t n_watchpoints = gb->n_watchpoints;
gb->n_watchpoints = 0;
uint8_t opcode = GB_read_memory(gb, gb->pc);
if (opcode == 0x76) {
gb->n_watchpoints = n_watchpoints;
if (gb->ime) { /* Already handled in above */
return JUMP_TO_NONE;
}
if (gb->interrupt_enable & gb->io_registers[GB_IO_IF] & 0x1F) {
return JUMP_TO_NONTRIVIAL; /* HALT bug could occur */
}
return JUMP_TO_NONE;
}
GB_opcode_address_getter_t *getter = opcodes[opcode];
if (!getter) {
gb->n_watchpoints = n_watchpoints;
return JUMP_TO_NONE;
}
uint16_t new_pc = getter(gb, opcode);
gb->n_watchpoints = n_watchpoints;
if (address) {
*address = new_pc;
}
return should_break(gb, new_pc, true) ? JUMP_TO_BREAK : JUMP_TO_NONE;
}

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@ -142,6 +142,9 @@ void GB_free(GB_gameboy_t *gb)
if (gb->sgb) {
free(gb->sgb);
}
if (gb->nontrivial_jump_state) {
free(gb->nontrivial_jump_state);
}
#ifndef DISABLE_DEBUGGER
GB_debugger_clear_symbols(gb);
#endif
@ -689,6 +692,11 @@ void GB_reset(GB_gameboy_t *gb)
GB_apu_update_cycles_per_sample(gb);
if (gb->nontrivial_jump_state) {
free(gb->nontrivial_jump_state);
gb->nontrivial_jump_state = NULL;
}
gb->magic = (uintptr_t)'SAME';
}

View File

@ -531,6 +531,9 @@ struct GB_gameboy_internal_s {
/* Breakpoints */
uint16_t n_breakpoints;
struct GB_breakpoint_s *breakpoints;
bool has_jump_to_breakpoints;
void *nontrivial_jump_state;
bool non_trivial_jump_breakpoint_occured;
/* SLD (Todo: merge with backtrace) */
bool stack_leak_detection;