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Add tetris-required changes #19

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96 changes: 91 additions & 5 deletions recompiler/src/code_generator.c
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Original file line number Diff line number Diff line change
Expand Up @@ -2041,6 +2041,63 @@ static bool return_adjust_func_matches(const GameConfig *cfg, uint16_t target) {
return false;
}

/* JSR targets whose callee consumes the pushed return address as data
* (e.g. inline bytecode trampolines that PLA it into a pointer). The
* pushed 3-byte frame is gone when the callee returns, so the post-call
* S check must restore S instead of bailing. */
static bool absorb_jsr_ret_matches(const GameConfig *cfg, uint16_t target) {
for (int i = 0; i < cfg->absorb_jsr_ret_count; i++) {
if (target == cfg->absorb_jsr_rets[i])
return true;
}
return false;
}

/* Is `addr` a genuine instruction START? Decodes forward from `base` (a
* known instruction boundary, e.g. the function's first byte) and reports
* whether the linear stream lands exactly on `addr` before reaching `limit`.
* Guards pattern-matchers that read single bytes (e.g. "previous byte ==
* 0x48 means PHA") against matching an OPERAND — e.g. Tetris $9CA2 `INC $48`
* has operand $48 immediately before a plain RTS ($9CA4), which the 2-PHA
* RTS-as-JMP detector mistook for PHA and turned the RTS into a stack-pop
* dispatch, corrupting S and jumping to $80C1/$3501. A misaligned decode
* (data tables, branch targets) yields false negatives only — those degrade
* to a plain RTS, which is always safe. */
static bool is_insn_boundary_from(const NESRom *rom, int bank, uint16_t base,
uint16_t addr, uint16_t limit) {
if (addr < base || addr >= limit) return false;
uint16_t a = base;
while (a < limit) {
if (a == addr) return true;
uint8_t op = rom_read(rom, bank, a);
int sz = g_opcode_table[op].size;
if (sz <= 0 || sz > 3) return false;
uint16_t next = (uint16_t)(a + sz);
if (next <= a) return false;
a = next;
}
return false;
}

/* JSR targets whose callee leaves the pushed return address on the 6502
* stack (its RTS is a plain C return that never touches S). Same post-call
* S restore as absorb_jsr_ret, but no site+5 goto — execution continues at
* site+3 (the ordinary 3-byte JSR fall-through). */
static bool restore_jsr_matches(const GameConfig *cfg, uint16_t target) {
for (int i = 0; i < cfg->restore_jsr_count; i++) {
if (target == cfg->restore_jsrs[i])
return true;
}
return false;
}

/* Inline-bytecode trampoline JSR sites (absorb_jsr_ret): the callee pops the
* JSR return as its script pointer and consumes the 2 ROM bytes after the
* JSR operand as inline script data, so on real hardware the interpreter's
* exit RTS resumes at site+5, not the ordinary fall-through site+3. The
* emitter handles this by returning 5 from emit_instruction so the next
* label lands at site+5 (see the MN_JSR absorb_jsr_ret case). */

#define DUMMY_PUSH_PAIR \
"g_ram[0x100+g_cpu.S]=0; g_cpu.S--; g_ram[0x100+g_cpu.S]=0; g_cpu.S--; "
#define DUMMY_JSR_PRE \
Expand Down Expand Up @@ -2948,6 +3005,30 @@ static int emit_instruction(FILE *f, const NESRom *rom, int bank,
if (is_yield_func(abs16)) {
/* Yield function: close the brace but skip the bail check */
fprintf(f, "}\n");
} else if (restore_jsr_matches(cfg, abs16)) {
/* Callee leaves the pushed frame on the 6502 stack (its
* RTS is a plain C return): restore S, no bail, and fall
* through to site+3 like a normal 3-byte JSR. */
fprintf(f, "if (g_cpu.S != _cbs) g_cpu.S = _cbs; }\n");
} else if (absorb_jsr_ret_matches(cfg, abs16)) {
/* Callee consumed the pushed return address as data
* (inline bytecode trampoline): restore S, no bail. */
fprintf(f, "if (g_cpu.S != _cbs) g_cpu.S = _cbs; }\n");
/* The interpreter's exit RTS resumes at site+5: it pops
* the pushed return (site+2) and the callee consumed the
* 2 inline data bytes after the operand. Falling through
* to site+3 would execute script DATA as code (verified
* on Tetris: $8217's site+3/4 are $17 $AD — script bytes,
* not instructions). Return 5 so the emitter continues at
* site+5 and emits its label there, making the goto valid.
* Same consumption model as inline_pointer (also returns
* 5). Non-trivial-bank mappers keep the old fall-through:
* window boundaries could leave label_site5 unemitted. */
if (rom->mapper != 4 && rom->mapper != 40) {
fprintf(f, "nes_cpu_instruction_boundary(0x%04X, 1); goto label_%04X; return;\n",
(uint16_t)(pc + 2), (uint16_t)(pc + 5));
return 5;
}
} else {
if (did_return_adjust_jsr) {
fprintf(f, "if (g_cpu.S == (uint8_t)(_cbs - 2) && g_rts_target != 0 && g_rts_target != _rp) { call_by_address((uint16_t)(g_rts_target + 1)); }\n");
Expand Down Expand Up @@ -3221,7 +3302,8 @@ static int emit_instruction(FILE *f, const NESRom *rom, int bank,
rom_read(rom, bank, pc-1) == 0x48 &&
rom_read(rom, bank, pc-5) == 0x48 &&
rom_read(rom, bank, pc-9) == 0x48 &&
rom_read(rom, bank, pc-12) == 0x48) {
rom_read(rom, bank, pc-12) == 0x48 &&
is_insn_boundary_from(rom, bank, func_base, pc, pc)) {
fprintf(f, "{ uint8_t _s4=g_cpu.S; g_cpu.S++; uint8_t _lo=g_ram[0x100+g_cpu.S]; g_cpu.S++; uint8_t _hi=g_ram[0x100+g_cpu.S]; call_by_address(((uint16_t)_hi<<8|_lo)+1); g_cpu.S=(uint8_t)(_s4+4); } goto label_%04X;\n ", (uint16_t)(pc+1));
/* Detect 2-PHA RTS-as-JMP: LDA hi/PHA / LDA lo/PHA / RTS.
* Also detect "outer continuation" pattern: function starts with
Expand All @@ -3230,7 +3312,8 @@ static int emit_instruction(FILE *f, const NESRom *rom, int bank,
* misses this because the PHAs are not at fixed offsets (computation
* breaks the pc-9/pc-12 spacing). After calling the inner handler,
* we must also call the static outer continuation. */
} else if (pc >= 0x8001 && (pc - 1) >= func_base && rom_read(rom, bank, pc - 1) == 0x48 /* PHA */) {
} else if (pc >= 0x8001 && (pc - 1) >= func_base && rom_read(rom, bank, pc - 1) == 0x48 /* PHA */ &&
is_insn_boundary_from(rom, bank, func_base, (uint16_t)(pc - 1), pc)) {
/* Check for outer continuation: scan backwards for LDA #hi/PHA/LDA #lo/PHA.
* Works both when the pattern is at func_base (original case) and when it
* starts at a branch-target block entry within the function (e.g., $BAD9
Expand Down Expand Up @@ -3642,7 +3725,8 @@ static void emit_function(FILE *f, const NESRom *rom, const FunctionEntry *fe,
rom_read(rom, bank, scan-1) == 0x48 &&
rom_read(rom, bank, scan-5) == 0x48 &&
rom_read(rom, bank, scan-9) == 0x48 &&
rom_read(rom, bank, scan-12) == 0x48) {
rom_read(rom, bank, scan-12) == 0x48 &&
is_insn_boundary_from(rom, bank, pc, scan, scan)) {
uint16_t cont = scan + 1;
bool found = false;
for (int p = 0; p < ps_pending_count; p++)
Expand Down Expand Up @@ -3849,7 +3933,8 @@ static void emit_function(FILE *f, const NESRom *rom, const FunctionEntry *fe,
rom_read(rom, bank, cursor-1) == 0x48 &&
rom_read(rom, bank, cursor-5) == 0x48 &&
rom_read(rom, bank, cursor-9) == 0x48 &&
rom_read(rom, bank, cursor-12) == 0x48) {
rom_read(rom, bank, cursor-12) == 0x48 &&
is_insn_boundary_from(rom, bank, pc, cursor, cursor)) {
uint16_t cont = cursor + 1;
bool found = false;
for (int p = 0; p < pending_count; p++)
Expand All @@ -3860,7 +3945,8 @@ static void emit_function(FILE *f, const NESRom *rom, const FunctionEntry *fe,
/* If this RTS is a direct branch target, the PHA setup was bypassed —
* emit a regular return instead of a 2-PHA dispatch. */
if (e->mnemonic == MN_RTS && cursor >= 0x8001 &&
rom_read(rom, bank, cursor - 1) == 0x48) {
rom_read(rom, bank, cursor - 1) == 0x48 &&
is_insn_boundary_from(rom, bank, pc, (uint16_t)(cursor - 1), cursor)) {
bool is_branch_tgt = false;
for (int b = 0; b < branch_targets_count; b++)
if (branch_targets[b] == cursor) { is_branch_tgt = true; break; }
Expand Down
14 changes: 14 additions & 0 deletions recompiler/src/game_config.c
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Expand Up @@ -335,6 +335,20 @@ static bool game_config_load_toml(GameConfig *cfg, const char *path) {
if (t) cfg->return_adjust_funcs[cfg->return_adjust_func_count++] = toml_hex(t, "addr");
}

/* [[absorb_jsr_ret]] */
toml_array_t *ajr = toml_array_in(root, "absorb_jsr_ret");
if (ajr) for (int i = 0; i < toml_array_nelem(ajr) && cfg->absorb_jsr_ret_count < GAME_CFG_MAX_NOP_JSRS; i++) {
toml_table_t *t = toml_table_at(ajr, i);
if (t) cfg->absorb_jsr_rets[cfg->absorb_jsr_ret_count++] = toml_hex(t, "addr");
}

/* [[restore_jsr]] */
toml_array_t *rjs = toml_array_in(root, "restore_jsr");
if (rjs) for (int i = 0; i < toml_array_nelem(rjs) && cfg->restore_jsr_count < GAME_CFG_MAX_NOP_JSRS; i++) {
toml_table_t *t = toml_table_at(rjs, i);
if (t) cfg->restore_jsrs[cfg->restore_jsr_count++] = toml_hex(t, "addr");
}

/* [[push_jmp]] — JMP targets that need a dummy push (bail-containing funcs).
* Optional `source` field restricts the push to a specific JMP site PC. */
toml_array_t *pjm = toml_array_in(root, "push_jmp");
Expand Down
13 changes: 13 additions & 0 deletions recompiler/src/game_config.h
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Expand Up @@ -283,6 +283,19 @@ typedef struct {
uint16_t return_adjust_funcs[GAME_CFG_MAX_NOP_JSRS]; /* JSR targets that rewrite their RTS operand */
int return_adjust_func_count;

/* JSR targets whose callee consumes the pushed return address as data
* (e.g. inline bytecode trampolines). At push_jsr sites for these targets
* the post-call S-mismatch bail is replaced with an S restore. */
uint16_t absorb_jsr_rets[GAME_CFG_MAX_NOP_JSRS];
int absorb_jsr_ret_count;

/* JSR targets whose callee leaves the pushed return address on the 6502
* stack (its RTS is a plain C return). At push_jsr sites for these
* targets the post-call S-mismatch bail is replaced with an S restore,
* and execution falls through to site+3 (no goto). */
uint16_t restore_jsrs[GAME_CFG_MAX_NOP_JSRS];
int restore_jsr_count;

struct {
uint16_t target; /* JMP destination that needs the dummy push */
uint16_t source; /* 0 = match any JMP site; nonzero = only this JMP source PC */
Expand Down
6 changes: 6 additions & 0 deletions runner/include/nes_runtime.h
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Expand Up @@ -442,6 +442,12 @@ extern uint64_t g_frame_count;
* the fixed-frame-length (29781) error. See DIFFERENTIAL-COSIM-PROPOSAL Rung 1. */
extern uint64_t g_nes_cycles;

/* Guest CPU-cycle stamp of the last VBlank frame boundary (pre-handler).
* Delta between consecutive boundary stamps = the true, essentially-constant
* frame length — the value audio pacing should use to size its per-frame
* sample push. */
extern uint64_t g_frame_boundary_cyc;

/* Save the current native framebuffer as a PNG */
void runner_screenshot(const char *path);

Expand Down
85 changes: 53 additions & 32 deletions runner/src/launcher.c
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Expand Up @@ -530,43 +530,61 @@ int main(int argc, char *argv[]) {
}
}
#endif

if (!gui_resolved)
if (argc >= 2 && argv[1][0] != '-') {
/* Backwards-compatible: ROM path given on command line */
strncpy(rom_path, argv[1], sizeof(rom_path) - 1);
/* Still verify CRC, but don't re-prompt on mismatch — just warn */
if (expected_crc != 0 && !verify_rom(rom_path, expected_crc)) {
fprintf(stderr, "[Launcher] Warning: CRC mismatch for '%s' — continuing anyway\n",
rom_path);
if (!gui_resolved) {
/* Check for explicit --rom <path> or --rom=<path> flag first. */
const char *explicit_rom = NULL;
for (int i = 1; i < argc; i++) {
if (strcmp(argv[i], "--rom") == 0 && i + 1 < argc) {
explicit_rom = argv[i + 1];
break;
}
if (strncmp(argv[i], "--rom=", 6) == 0) {
explicit_rom = argv[i] + 6;
break;
}
}
} else {
/* Try rom.cfg first */
rom_cfg_read(rom_path, sizeof(rom_path));

int valid = 0;
while (!valid) {
if (rom_path[0] == '\0') {
/* No saved path — open picker */
if (!pick_rom_file(rom_path, sizeof(rom_path))) {
fprintf(stderr, "[Launcher] No ROM selected — exiting.\n");
return 1;
}
if (explicit_rom && explicit_rom[0] != '\0') {
strncpy(rom_path, explicit_rom, sizeof(rom_path) - 1);
/* Still verify CRC, but do not re-prompt on mismatch — just warn */
if (expected_crc != 0 && !verify_rom(rom_path, expected_crc)) {
fprintf(stderr, "[Launcher] Warning: CRC mismatch for '%s' — continuing anyway\n",
rom_path);
}
} else if (argc >= 2 && argv[1][0] != '-') {
/* Backwards-compatible: ROM path given on command line */
strncpy(rom_path, argv[1], sizeof(rom_path) - 1);
/* Still verify CRC, but don't re-prompt on mismatch — just warn */
if (expected_crc != 0 && !verify_rom(rom_path, expected_crc)) {
fprintf(stderr, "[Launcher] Warning: CRC mismatch for '%s' — continuing anyway\n",
rom_path);
}
} else {
/* Try rom.cfg first */
rom_cfg_read(rom_path, sizeof(rom_path));

int valid = 0;
while (!valid) {
if (rom_path[0] == '\0') {
/* No saved path — open picker */
if (!pick_rom_file(rom_path, sizeof(rom_path))) {
fprintf(stderr, "[Launcher] No ROM selected — exiting.\n");
return 1;
}
}

/* Verify the ROM */
if (verify_rom(rom_path, expected_crc)) {
valid = 1;
} else {
/* Wrong file — clear path and pick again */
rom_path[0] = '\0';
/* Verify the ROM */
if (verify_rom(rom_path, expected_crc)) {
valid = 1;
} else {
/* Wrong file — clear path and pick again */
rom_path[0] = '\0';
}
}
}

rom_cfg_write(rom_path);
printf("[Launcher] ROM: %s\n", rom_path);
rom_cfg_write(rom_path);
printf("[Launcher] ROM: %s\n", rom_path);
}
}

/* Re-build argv so that argv[1] == rom_path for the runner.
* If argv[1] was the ROM path, extra args start at index 2.
* If argv[1] was a flag (starts with '-'), forward all args from index 1. */
Expand All @@ -575,8 +593,11 @@ int main(int argc, char *argv[]) {
int extra_start = (argc >= 2 && argv[1][0] != '-') ? 2 : 1;
new_argv[new_argc++] = argv[0];
new_argv[new_argc++] = rom_path;
for (int i = extra_start; i < argc && new_argc < 63; i++)
for (int i = extra_start; i < argc && new_argc < 63; i++) {
if (strcmp(argv[i], "--rom") == 0 && i + 1 < argc) { i++; continue; }
if (strncmp(argv[i], "--rom=", 6) == 0) continue;
new_argv[new_argc++] = argv[i];
}
new_argv[new_argc] = NULL;

#if NESRECOMP_ENABLE_MODS
Expand Down
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