Files
psxrecomp/runtime/include/cpu_state.h
T
Matthew Stanley be76e4d4b5 widescreen: [video] aspect_ratio — GTE X-squash + stretched present
Adds the DuckStation-style widescreen hack as a config option,
implemented in the runtime (no regen needed):

- gte.cpp: gte_set_display_aspect(num, den). RTPS/RTPT scale the
  IR1*h/sz screen-X term by (4*den)/(3*num) around the game's own
  OFX projection centre (identity at 4:3). Games cull against the
  SXY values they read back from us, so post-projection screen-
  bounds culls stay aligned with the visible frame.
- present: GL letterbox_rect generalised to the configured aspect
  (gl_renderer_set_display_aspect); SDL_Renderer path gets an
  aspect-derived logical size + dst rect. Window opens at the
  configured aspect (clamp_window_4x3 -> clamp_window_aspect).
- config: [video] aspect_ratio = W:H (4:3 default, 16:9, up
  to 32:9) in game.toml, settings.toml (load+save), launcher seed.

World geometry keeps correct proportions on the stretched present;
screen-space 2D (HUD, FMV, sprite quad widths) stretches — the
known limitation of the squash tier. EXPERIMENTAL.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-06-15 12:52:14 -07:00

142 lines
6.6 KiB
C

/* ============================================================================
* cpu_state.h — Phase 2 runtime version
* ----------------------------------------------------------------------------
* This is the RUNTIME version of the CPUState header. It has the same struct
* layout as generated/cpu_state.h (Phase 1a compile-only artifact) but is
* intended to be linked into a runnable binary.
*
* The generated C files (SCPH1001_full.c, SCPH1001_dispatch.c) include
* "cpu_state.h" and the build uses -I runtime/include so they find this file.
* ========================================================================== */
#ifndef PSXRECOMP_CPU_STATE_H
#define PSXRECOMP_CPU_STATE_H
#include <stdint.h>
#ifdef __cplusplus
extern "C" {
#endif
typedef struct CPUState {
uint32_t gpr[32]; /* $0..$31; gpr[0] is hardwired zero, never written */
uint32_t pc; /* program counter */
uint32_t hi, lo; /* mult/div result registers */
uint32_t cop0[32]; /* COP0 system control registers (SR, Cause, EPC, ...) */
uint32_t gte_data[32]; /* COP2 (GTE) data registers */
uint32_t gte_ctrl[32]; /* COP2 (GTE) control registers */
/* Memory access function pointers -- wired at init to psx_read/psx_write. */
uint32_t (*read_word)(uint32_t addr);
void (*write_word)(uint32_t addr, uint32_t value);
uint16_t (*read_half)(uint32_t addr);
void (*write_half)(uint32_t addr, uint16_t value);
uint8_t (*read_byte)(uint32_t addr);
void (*write_byte)(uint32_t addr, uint8_t value);
} CPUState;
/* Trap trampolines — defined in runtime/src/traps.c */
extern void psx_syscall(CPUState* cpu, uint32_t code);
extern void psx_arith_overflow(CPUState* cpu);
extern void psx_unaligned_access(CPUState* cpu, uint32_t addr, uint32_t pc);
extern void psx_break(CPUState* cpu, uint32_t code, uint32_t pc);
/* Dispatch — defined in generated/SCPH1001_dispatch.c */
extern void psx_dispatch(CPUState* cpu, uint32_t target_addr);
extern void psx_dispatch_call(CPUState* cpu, uint32_t target_addr, uint32_t return_addr);
/* Unknown dispatch — defined in runtime/src/traps.c */
extern void psx_unknown_dispatch(CPUState* cpu, uint32_t addr, uint32_t phys);
/* GTE (COP2) — defined in runtime/src/gte.cpp */
extern void gte_execute(CPUState* cpu, uint32_t cmd);
/* Widescreen X-squash: display aspect num:den (4,3 = identity/off). Scales
* RTPS/RTPT screen-X around the game's OFX so a 4:3 frame stretched to the
* wide aspect shows a wider field of view. */
extern void gte_set_display_aspect(int num, int den);
extern uint32_t gte_read_data(CPUState* cpu, uint8_t reg);
extern uint32_t gte_read_ctrl(CPUState* cpu, uint8_t reg);
extern void gte_write_data(CPUState* cpu, uint8_t reg, uint32_t val);
extern void gte_write_ctrl(CPUState* cpu, uint8_t reg, uint32_t val);
/* ============================================================================
* Dispatch call contract (Bug D / wild-return family fix)
* ----------------------------------------------------------------------------
* Generated C continuations mirror the guest call graph: after `jal F`, the C
* code calls F's C function and then falls into the continuation block. Real
* hardware has only one stack; if F's flow goes wild (returns to an address
* other than the call site's $ra, or with a shifted $sp — e.g. a mid-function
* entry running an epilogue for a frame it never pushed), the hardware simply
* keeps executing wherever the guest jumped, and the interrupted caller's
* code never resumes. Our C model, by contrast, resumes the suspended C
* continuation whenever the C call returns — re-executing tails on a moved
* guest stack (the Bug A/C/D zombie family).
*
* The contract: a C continuation may run ONLY if the guest actually arrived
* at it — i.e. the callee came back with $ra == the call site's return
* address and $sp == the caller's stack pointer at the call. When the
* contract is violated, we begin a "bail" unwind: cpu->pc is set to the
* guest's true target (the wild jr's destination), g_psx_call_bail is set,
* and every generated frame returns immediately without running its
* continuation. The unwind resolves at the first enclosing call site (or
* dispatch loop) whose (return address, sp) contract matches the guest's
* arrival state; if none matches, the outermost dispatch loop clears the
* flag and tail-dispatches the wild target with a clean host stack.
*
* g_psx_call_bail is defined in runtime/src/traps.c. Overlay DLLs share
* the runtime's state through pointers wired by overlay_init (the
* PSX_OVERLAY_DLL_BUILD branch; see overlay_api.h / compile_overlays.py).
* ========================================================================== */
#ifdef PSX_OVERLAY_DLL_BUILD
extern int *g_psx_call_bail_p;
extern uint64_t *g_psx_bail_first_p;
extern uint64_t *g_psx_bail_resolved_p;
#define g_psx_call_bail (*g_psx_call_bail_p)
#define g_psx_bail_first (*g_psx_bail_first_p)
#define g_psx_bail_resolved (*g_psx_bail_resolved_p)
#else
extern int g_psx_call_bail;
extern uint64_t g_psx_bail_first; /* contract violations detected */
extern uint64_t g_psx_bail_resolved; /* unwinds resolved at a call site */
extern uint64_t g_psx_bail_flattened; /* unwinds flattened at outermost */
extern uint64_t g_psx_bail_anomaly; /* bail flag seen where impossible */
#endif
/* Validate a direct call site after the callee's C return.
* Returns 1 if the caller must `return;` immediately (bail in progress),
* 0 if the continuation is valid. site_ra = the call's return address,
* site_sp = guest $sp recorded immediately before the call. */
static inline int psx_call_contract(CPUState* cpu, uint32_t site_ra,
uint32_t site_sp) {
if (g_psx_call_bail) {
/* An inner frame began a bail unwind. Resolve here iff the guest's
* arrival state matches this site's contract. */
if (((cpu->pc ^ site_ra) & 0x1FFFFFFFu) == 0 &&
cpu->gpr[29] == site_sp) {
g_psx_call_bail = 0;
g_psx_bail_resolved++;
cpu->pc = 0;
return 0;
}
return 1;
}
if (cpu->gpr[29] != site_sp ||
((cpu->gpr[31] ^ site_ra) & 0x1FFFFFFFu) != 0) {
/* First detection: the callee C-returned but the guest did not
* return here. $ra holds the wild jr's true destination (the
* longjmp-return emission sets cpu->pc = $ra before returning,
* which is the same value). */
g_psx_call_bail = 1;
g_psx_bail_first++;
cpu->pc = cpu->gpr[31];
return 1;
}
return 0;
}
#ifdef __cplusplus
}
#endif
#endif /* PSXRECOMP_CPU_STATE_H */