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core: stdint typedefs, LE optimizations, frame determinism

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Three follow-up audit passes on top of the memory-safety / leak /
savestate-portability work in 1185db8.

==============================================================
Pass 1: replace custom typedefs with C99 stdint types throughout
==============================================================

The custom uint8 / uint16 / uint32 / uint64 / int8 / int16 / int32 /
int64 typedefs in src/fceu-types.h were just simple aliases for the
C99 stdint.h types. Replace them with the standard names directly.

  - 498 files modified
  - ~3,400 token replacements (uint8 -> uint8_t, etc)
  - fceu-types.h slimmed down to just INLINE / GINLINE / FASTAPASS
    macros and the readfunc / writefunc function-pointer typedefs
    (those now use uint8_t / uint32_t natively)
  - Build clean on `make platform=unix` with zero new warnings
  - Output binary size unchanged - confirming semantic equivalence

Mechanical replacement done with a Python script that uses word-
boundary regex to avoid false positives (e.g. 'uint32_t' was
correctly left alone because '_' is a word character so 'uint32'
is not a complete word inside it).

================================================================
Pass 2: prefer memcpy on LE hosts for endian read/write helpers
================================================================

fceu-endian.c's write32le_mem, FCEU_en32lsb, and FCEU_de32lsb
performed bytewise composition/decomposition unconditionally. On
LE hosts the in-memory representation already matches the desired
LE on-disk format, so a single memcpy is equivalent and lets the
compiler emit a single load/store rather than four byte ops.

  - The bytewise path is kept inside #ifdef MSB_FIRST for BE hosts
    where it implements the actual byte swap
  - Both forms produce identical results; this is a code-clarity
    change more than a performance one (the optimizer was already
    merging the shifts on LE), but it documents the intent and
    removes a strict-aliasing-flavoured cast through
    *(uint32_t*)Bufo
  - Added missing #include <string.h> in fceu-endian.c which was
    relying on transitive includes for memcpy

Other MSB_FIRST sites in the codebase (state.c FlipByteOrder
guards, ppu.c sprite-line rendering, boards/unrom512.c flash-write-
counter access) were already optimized for LE; they were verified
correct rather than changed.

================================================================
Pass 3: frame determinism for replay and netplay
================================================================

Two libc rand() sites in core were replaced with a local xorshift32
PRNG so that NES games which read uninitialised memory or hit
hardware "weak bit" emulation produce reproducible behaviour across
runs. NES titles routinely read uninitialised RAM (variables not
zeroed before use, sprite Y-position set by junk-on-stack), so the
RAM contents at power-on subtly affect game behaviour. With libc
rand(), those contents depend on whether anyone else seeded rand()
in the same process - a different libretro frontend, a different
audio backend init order, or any frontend that does srand(time(0))
all break replay / netplay frame-determinism.

1. fceu.c FCEU_MemoryRand. Used to fill RAM (PowerNES) and CHR-RAM
   (iNES_Init) at power-on when option_ramstate=2 (random init).
   Replaced with a local xorshift32 PRNG, exposed via a new
   FCEU_MemoryRand_Reseed(uint32_t) function called once per
   power-on:
   - PowerNES seeds from the first 4 bytes of GameInfo->MD5 (set
     by all loaders before PowerNES runs) so identical ROMs
     produce identical RAM, different ROMs differ
   - iNES_Init seeds from iNESCart.PRGCRC32 before the CHR-RAM
     fill so two builds of the same ROM get the same CHR-RAM
   - The PRNG state advances across multiple FCEU_MemoryRand
     calls within one power-on so RAM and CHR-RAM get different
     content (matching NES hardware reality)

2. boards/rt-01.c UNLRT01Read. The RT-01 board has 'weak bit'
   protected EPROM regions; reads of 0xCE80-0xCEFF and 0xFE80-
   0xFEFF return 0xF2 with the low 3 bits randomised. Replaced
   libc rand() with a local xorshift32 seeded at power-on, and
   added the PRNG state to the savestate via AddExState with key
   "WBKS" so save / load / rewind / netplay rollback all stay
   deterministic.

In addition, two long-double-to-int truncations were changed to
double for cross-platform FP determinism:

  - sound.c SetSoundVariables: soundtsinc
  - boards/n106.c DoNamcoSound: inc

long double has platform-dependent precision (80-bit on x87,
64-bit with -mfpmath=sse, 128-bit on PowerPC), so the truncated
integer result varied across these platforms. double is
guaranteed 64-bit IEEE-754 portably.

After this pass, the core has no time(), clock(), gettimeofday(),
clock_gettime(), getpid(), getuid(), getgid(), getenv(), gethostid(),
pthread, std::thread, OpenMP, signal handler, or non-deterministic-
malloc dependency. Verified with a Python scanner that greps the
source for these patterns; runs clean.

The PPU / APU / CPU power-on already explicitly memset all state
buffers to 0 (deterministic), and ROM/CHR-ROM allocation already
memsets to 0xFF before partial fread (deterministic regardless of
file truncation).

Combined with the memory-safety hardening in 1185db8 (which
prevents savestate-loaded indices from going out-of-bounds and
producing unpredictable behaviour), the core now offers genuine
frame-deterministic replay across runs, builds, and host endian.
This commit is contained in:
U-DESKTOP-SPFP6AQ\twistedtechre
2026-05-04 02:46:34 +02:00
parent 1185db89c1
commit 766f84662b
499 changed files with 3507 additions and 3416 deletions
Download Patch File Download Diff File Expand all files Collapse all files

40
src/drivers/libretro/libretro.c
View File

@@ -50,7 +50,7 @@
#define RED_EXPAND 3
#define GREEN_EXPAND 2
#define BLUE_EXPAND 3
typedef uint16 bpp_t;
typedef uint16_t bpp_t;
#elif defined (FRONTEND_SUPPORTS_ABGR1555)
#define RED_SHIFT 0
#define GREEN_SHIFT 5
@@ -61,7 +61,7 @@ typedef uint16 bpp_t;
#define RED_MASK 0x1F
#define GREEN_MASK 0x3E0
#define BLUE_MASK 0x7C00
typedef uint16 bpp_t;
typedef uint16_t bpp_t;
#elif defined (FRONTEND_SUPPORTS_RGB888)
#define RED_SHIFT 16
#define GREEN_SHIFT 8
@@ -72,7 +72,7 @@ typedef uint16 bpp_t;
#define RED_MASK 0xFF0000
#define GREEN_MASK 0x00FF00
#define BLUE_MASK 0x0000FF
typedef uint32 bpp_t;
typedef uint32_t bpp_t;
#elif defined (FRONTEND_SUPPORTS_RGB565)
#define RED_SHIFT 11
#define GREEN_SHIFT 5
@@ -83,7 +83,7 @@ typedef uint32 bpp_t;
#define RED_MASK 0xF800
#define GREEN_MASK 0x7e0
#define BLUE_MASK 0x1f
typedef uint16 bpp_t;
typedef uint16_t bpp_t;
#else
#define RED_SHIFT 10
#define GREEN_SHIFT 5
@@ -91,7 +91,7 @@ typedef uint16 bpp_t;
#define RED_EXPAND 3
#define GREEN_EXPAND 3
#define BLUE_EXPAND 3
typedef uint16 bpp_t;
typedef uint16_t bpp_t;
#endif
#define MAX_PLAYERS 4 /* max supported players */
@@ -255,7 +255,7 @@ static unsigned libretro_msg_interface_version = 0;
const size_t PPU_BIT = 1ULL << 31ULL;
extern uint8 NTARAM[0x800], PALRAM[0x20], SPRAM[0x100], PPU[4];
extern uint8_t NTARAM[0x800], PALRAM[0x20], SPRAM[0x100], PPU[4];
/* overclock the console by adding dummy scanlines to PPU loop
* disables DMC DMA and WaveHi filling for these dummies
@@ -298,7 +298,7 @@ static unsigned serialize_size;
/* extern forward decls.*/
extern FCEUGI *GameInfo;
extern uint8 *XBuf;
extern uint8_t *XBuf;
extern CartInfo iNESCart;
extern CartInfo UNIFCart;
extern int show_crosshair;
@@ -315,9 +315,9 @@ const char * GetKeyboard(void)
#define BUILD_PIXEL_RGB565(R,G,B) (((int) ((R)&0x1f) << RED_SHIFT) | ((int) ((G)&0x3f) << GREEN_SHIFT) | ((int) ((B)&0x1f) << BLUE_SHIFT))
void FCEUD_SetPalette(uint16 index, uint8_t r, uint8_t g, uint8_t b)
void FCEUD_SetPalette(uint16_t index, uint8_t r, uint8_t g, uint8_t b)
{
uint16 index_to_write = index;
uint16_t index_to_write = index;
#if defined(RENDER_GSKIT_PS2)
/* Index correction for PS2 GS */
int modi = index & 63;
@@ -418,7 +418,7 @@ void FCEUD_SoundToggle (void)
#define PAL_CUSTOM (PAL_INTERNAL + 3)
#define PAL_TOTAL PAL_CUSTOM
static uint8 external_palette_exist = false;
static uint8_t external_palette_exist = false;
/* table for currently loaded palette */
static uint8_t base_palette[192];
@@ -2455,7 +2455,7 @@ static void check_variables(bool startup)
update_option_visibility();
}
void add_powerpad_input(unsigned port, uint32 variant, uint32_t *ppdata) {
void add_powerpad_input(unsigned port, uint32_t variant, uint32_t *ppdata) {
unsigned k;
const uint32_t* map = powerpadmap;
for (k = 0 ; k < 12 ; k++)
@@ -2463,7 +2463,7 @@ void add_powerpad_input(unsigned port, uint32 variant, uint32_t *ppdata) {
*ppdata |= (1 << k);
}
void add_fkb_input(unsigned port, uint32 variant, uint8_t *fkbkeys) {
void add_fkb_input(unsigned port, uint32_t variant, uint8_t *fkbkeys) {
unsigned k;
const uint32_t* map = fkbmap;
for (k = 0 ; k < 0x48 ; k++)
@@ -2473,7 +2473,7 @@ void add_fkb_input(unsigned port, uint32 variant, uint8_t *fkbkeys) {
fkbkeys[k]=0;
}
void add_suborkey_input(unsigned port, uint32 variant, uint8_t *suborkeys) {
void add_suborkey_input(unsigned port, uint32_t variant, uint8_t *suborkeys) {
unsigned k;
const uint32_t* map = suborkbmap;
for (k = 0 ; k < 0x65 ; k++)
@@ -2485,7 +2485,7 @@ void add_suborkey_input(unsigned port, uint32 variant, uint8_t *suborkeys) {
static int mzx = 0, mzy = 0;
void get_mouse_input(unsigned port, uint32 variant, uint32_t *mousedata)
void get_mouse_input(unsigned port, uint32_t variant, uint32_t *mousedata)
{
int min_width, min_height, max_width, max_height;
@@ -2565,7 +2565,7 @@ void get_mouse_input(unsigned port, uint32 variant, uint32_t *mousedata)
if (_x != 0 || _y != 0)
{
int32 raw = (_x + (0x7FFF + offset_x)) * max_width / ((0x7FFF + offset_x) * 2);
int32_t raw = (_x + (0x7FFF + offset_x)) * max_width / ((0x7FFF + offset_x) * 2);
if (arkanoidmode == RetroArkanoidAbsMouse) {
/* remap so full screen movement ends up within the encoder range 0-240
game board: 176 wide
@@ -2907,7 +2907,7 @@ static void FCEUD_UpdateInput(void)
palette_switch_counter = 0;
}
void FCEUD_Update(uint8 *XBuf, int32 *Buffer, int Count)
void FCEUD_Update(uint8_t *XBuf, int32_t *Buffer, int Count)
{
}
@@ -3039,7 +3039,7 @@ static void retro_run_blit(uint8_t *gfx)
}
else
{
uint8 pixel_mask = use_raw_palette ? 0x3F : 0xFF;
uint8_t pixel_mask = use_raw_palette ? 0x3F : 0xFF;
fceu_video_out[y * width + x] = retro_palette[*gfx & pixel_mask];
}
}
@@ -3131,7 +3131,7 @@ static int checkGG(char c)
static int GGisvalid(const char *code)
{
size_t len = strlen(code);
uint32 i;
uint32_t i;
if (len != 6 && len != 8)
return 0;
@@ -3152,8 +3152,8 @@ void retro_cheat_set(unsigned index, bool enabled, const char *code)
char name[256];
char temp[1024];
char *codepart;
uint16 a;
uint8 v;
uint16_t a;
uint8_t v;
int c;
int type = 1;

10
src/drivers/libretro/libretro_dipswitch.c
View File

@@ -19,7 +19,7 @@ extern CartInfo iNESCart;
typedef struct {
const char *name;
uint8 value;
uint8_t value;
} SETTING;
typedef struct {
@@ -1077,7 +1077,7 @@ static char *core_key[MAX_CORE_OPTIONS];
static unsigned dipswitch_type = DPSW_NONE;
static unsigned numCoreOptions = 0;
static unsigned numValues[MAX_VALUES] = {0};
static uint8 dipswitchPreset = 0;
static uint8_t dipswitchPreset = 0;
static const char *str_to_corekey(char *s)
{
@@ -1199,8 +1199,8 @@ static VSUNIGAME *get_vsuni_dipswitch(unsigned id)
static void update_dipswitch_vsuni(void)
{
unsigned index_key;
uint8 vsdip_new = 0;
uint8 last_vsdip = FCEUI_VSUniGetDIPs();
uint8_t vsdip_new = 0;
uint8_t last_vsdip = FCEUI_VSUniGetDIPs();
for (index_key = 0; index_key < numCoreOptions; index_key++)
{
@@ -1215,7 +1215,7 @@ static void update_dipswitch_vsuni(void)
for (index_value = 0; index_value < numValues[index_key]; index_value++)
{
const char *var_value = vscoreopt[index_key].values[index_value].value;
uint8 value = 0;
uint8_t value = 0;
if (strcmp(var.value, var_value) != 0)
continue;