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pikuma_ps1/code/duffle/lottes_tape.h
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2026-07-08 00:30:02 -04:00

274 lines
12 KiB
C

#ifdef INTELLISENSE_DIRECTIVES
# pragma once
# include "dsl.h"
# include "gcc_asm.h"
# include "mips.h"
# include "gte.h"
# include "memory.h"
# include "atom_dsl.h"
#endif
typedef U4 const MipsCode;
#define MipsAtom_(sym) MipsCode tmpl(code,sym) [] align_(4) =
#pragma region Tape Drive
/* ---------------------------------------------------------------------------
* TAPE DRIVE ABI & REGISTER ALIASES
* ---------------------------------------------------------------------------
* We map the MIPS temporary registers to a persistent global workspace.
* The C compiler is completely unaware of these bindings.
* ---------------------------------------------------------------------------*/
enum {
R_AtomJmp = R_T9,
R_TapePtr = R_T8, /* The Instruction Stream Pointer */
R_InCursor = R_T4, /* Input data cursor */
R_PrimCursor = R_T7, /* VRAM output cursor (primitive buffer) */
R_FaceCursor = R_T4, /* Input data cursor (indices/faces) */
R_VertBase = R_T5, /* Base address of the vertex array */
R_OtBase = R_T6, /* Base address of the Ordering Table */
/* Stringification codes for the GCC inline assembler clobber lists */
#define R_TapePtr_Code R_T8_Code
#define R_InCursor_Code R_T4_Code
#define R_PrimCursor_Code R_T7_Code
#define R_FaceCursor_Code R_T4_Code
#define R_VertBase_Code R_T5_Code
#define R_OtBase_Code R_T6_Code
};
/* The 'Exit' Atom */
MipsAtom_(tape_exit) { jump_reg(rret_addr), nop };
/* Generalized Tape Engine Runner */
FI_ void tape_run(Slice_U4 tape) { register U4* tp rgcc(R_TapePtr) = tape.ptr; asm volatile(
asm_words(
add_ui( R_SP, R_SP, -MipsStackAlignment) /* Allocate stack space */
, store_word(R_RA, R_SP, 0) /* Safely backup $ra to the stack */
, load_word( R_AtomJmp, R_TapePtr, 0) /* Bootstrap the first jump */
, add_ui_self( R_TapePtr, S_(MipsCode)) /* Advance tape */
, call_reg( R_AtomJmp) /* jalr $t9 */
, nop /* Branch delay slot */
, load_word(R_RA, R_SP, 0) /* Restore $ra from stack */
, add_ui_self( R_SP, MipsStackAlignment) /* Deallocate stack space */
)
asm_rpins, r_use(tp)
asm_clobber:
rlit(R_AT)
, rlit(R_V0), rlit(R_V1)
, rlit(R_T0), rlit(R_T1), rlit(R_T2), rlit(R_T3)
/* Tell GCC the tape engine owns and destroys the workspace registers */
, rlit(R_PrimCursor), rlit(R_FaceCursor), rlit(R_VertBase), rlit(R_OtBase)
, rlit(R_T9)
, clb_mem_drain
); }
typedef Relative_(FArena) Struct_(TapeBuilder) { U4 ptr; U4 capacity; U4 used; };
FI_ void tb_init(TapeBuilder* tb, FArena* arena) { tb->ptr = arena->start; tb->used = 0; }
FI_ TapeBuilder tb_make_old( FArena* arena) { return (TapeBuilder){ arena->start, 0 }; }
FI_ TapeBuilder tb_make(Slice mem) { return (TapeBuilder){ mem.ptr, mem.len, 0 }; }
#define tb_emit_(tb, atom) tb_emit(tb, tmpl(code,atom))
FI_ void tb_emit(TapeBuilder* tb, MipsCode* atom) { u4_r(tb->ptr)[tb->used] = u4_(atom); ++ tb->used; }
FI_ void tb_data(TapeBuilder* tb, U4 data) { u4_r(tb->ptr)[tb->used] = u4_(data); ++ tb->used; }
FI_ Slice_U4 tb_end (TapeBuilder* tb) { tb_emit(tb,code_tape_exit); return (Slice_U4){ C_(U4*,tb->ptr), tb->used }; }
FI_ Slice_U4 tb_slice(TapeBuilder tb) { return (Slice_U4){ C_(U4*,tb.ptr), tb.used }; }
#define tb_scope(tb) for(U4 tbs_once=0;tbs_once==0;++tbs_once,tb_emit(tb,code_tape_exit))
#pragma endregion Tape Drive
#pragma region Macro Mips Atom Components
/* ---------------------------------------------------------------------------
* MACRO ATOM Components (Reusable Assembly Components)
* These do NOT yield. They are expanded inline inside Tape Atoms.
* ---------------------------------------------------------------------------*/
/* The 'Yield' sequence for Tape Atoms.
* Loads the next pointer from the tape, advances the tape, and jumps.
* Cost: ~ 4 cycles */
#define mac_yield() \
load_word(R_AtomJmp, R_TapePtr, 0) \
, add_ui_self( R_TapePtr, S_(MipsCode)) \
, jump_reg( R_AtomJmp) \
, nop
/* Words: 3; Loads 3 S2 indices from the face array */
#define mac_load_tri_indices(rId_0, rId_1, rId_2) \
load_half_u(rId_0, R_FaceCursor, 0 * S_(S2)) \
, load_half_u(rId_1, R_FaceCursor, 1 * S_(S2)) \
, load_half_u(rId_2, R_FaceCursor, 2 * S_(S2))
/* Words: 18; Translates indices to vertex addresses and pushes them to GTE */
#define mac_load_tri_verts(rId_0, rId_1, rId_2) \
shift_lleft(R_AT, rId_0, v3s2_byteoff), add_u_self(R_AT, R_VertBase), load_word(R_V0, R_AT, O_(V3_S2,x)), load_word(R_V1, R_AT, O_(V3_S2,z)), gte_mt(R_V0, C2_VXY0), gte_mt(R_V1, C2_VZ0) \
, shift_lleft(R_AT, rId_1, v3s2_byteoff), add_u_self(R_AT, R_VertBase), load_word(R_V0, R_AT, O_(V3_S2,x)), load_word(R_V1, R_AT, O_(V3_S2,z)), gte_mt(R_V0, C2_VXY1), gte_mt(R_V1, C2_VZ1) \
, shift_lleft(R_AT, rId_2, v3s2_byteoff), add_u_self(R_AT, R_VertBase), load_word(R_V0, R_AT, O_(V3_S2,x)), load_word(R_V1, R_AT, O_(V3_S2,z)), gte_mt(R_V0, C2_VXY2), gte_mt(R_V1, C2_VZ2)
/* Words: 11; Correctly inserts a primitive into the Ordering Table linked list */
#define mac_insert_ot_tag(r_otz, prim_length) \
shift_lleft( R_T1, r_otz, 2) /* T1 = r_otz * S_(U4) */ \
, add_u( R_T1, R_T1, R_OtBase) /* T1 = & OrderingTable[OTZ] */ \
, load_word( R_AT, R_T1, O_(PolyTag,bf_addr_len)) /* AT = old_ot_head */ \
, load_upper_i(R_V0, prim_length) /* V0 = prim_length << 16 (high 16 bits of a tag) */ \
, mask_upper( R_AT, R_AT, S_(PolyTag_len_bits)) /* Strip upper 8 bits (length from prev cell) → keep only low 24 */ \
, or_u( R_AT, R_AT, R_V0) /* Merge length */ \
, store_word( R_AT, R_PrimCursor, O_(PolyTag,bf_addr_len)) /* prim->tag = packed(prim_length, old_addr) */ \
, shift_lleft( R_AT, R_PrimCursor, S_(PolyTag_len_bits)) /* AT = (prim_length << 24) | old_addr */ \
, shift_lright(R_AT, R_AT, S_(PolyTag_len_bits)) \
, store_word( R_AT, R_T1, O_(PolyTag,bf_addr_len)) /* OrderingTable[OTZ] = PrimCursor */
#pragma endregion Macro Atom Components
#pragma region Mips Atom Builder
// This allows for runtime procedural authoring of mips atoms.
typedef Struct_(FMipsAtom512) { U4 data[512]; U4 used; };
typedef Slice_(MipsCode); typedef Slice_MipsCode MipsAtom;
// FArena Related
typedef Relative_(FArena) Struct_(MipsAtomBuilder) { U4 start; U4 capacity; U4 used; };
// Whatever the builder is writting to should most likely coresspond
// to something that can fit within instruction cache?
FI_ void atombuilder_unroll(MipsAtomBuilder_R ab, Slice_MipsCode_R code) {
assert(ab->capacity - ab->used - code->len);
mem_copy(ab->start, u4_(code->ptr), code->len);
mem_bump(ab->start, ab->capacity, & ab->used, code->len);
}
#define atombuilder_unroll_mac(ab, mac) atombuilder_unroll(ab, slice_arg_from_array(Slice_MipsCode, mac))
// When done authoring, utilize this to cap-off the atom
FI_ void atombuilder_end(MipsAtomBuilder_R ab) {
LP_ MipsAtom_(yield) { mac_yield() };
mem_copy(ab->start, u4_(code_yield), S_(code_yield));
mem_bump(ab->start, ab->capacity, & ab->used, S_(code_yield));
}
#define mipsatom_from_builder(ab) (MipsAtom){ab.start, ab.used}
#pragma endregion Mips Atom Builder
#pragma region Baked Mips Atoms
// These atoms are resolved at compile time and are (usually) statically linked readonly data.
enum {
bios_flushcache = 0x44,
bios_table_addr = 0xA0,
};
/* Flushes the Instruction Cache (PSX A-function 0x44 via BIOS stub at 0xA0).
*
* Sequence (per MIPS ABI; arguments in arg registers, RA pushed to stack):
* 1. sp -= 8; sw $ra, 4($sp) ; save RA
* 2. $a0 = bios_flushcache (arg0)
* 3. $t0 = bios_table_addr ; t0 = &BIOS A-function table
* 4. jalr $t0, $ra ; call BIOS(flushcache)
* nop ; branch delay slot
* 5. lw $ra, 4($sp); jr $ra ; restore & return
* 6. sp += 8
*/
internal MipsAtom_(mips_flush_icache) {
add_ui(rstack_ptr, rstack_ptr, -MipsStackAlignment) /* sp -= 8 */
, store_word(rret_addr, rstack_ptr, S_(U4)) /* sw $ra, 4($sp) */
, add_ui(rret_0, rdiscard, bios_flushcache) /* addiu $a0, $0, 0x44 */
, add_ui(rtmp_0, rdiscard, bios_table_addr) /* addiu $t0, $0, 0xA0 */
, jump_link(rtmp_0, rret_addr) /* jalr $t0, $ra */
, nop /* BD slot */
, load_word(rret_addr, rstack_ptr, S_(U4)) /* lw $ra, 4($sp) */
, jump_reg(rret_addr) /* jr $ra */
, add_ui(rstack_ptr, rstack_ptr, MipsStackAlignment) /* sp += 8 (BD) */
, mac_yield()
};
typedef Struct_(Binds_SetGteWorld) {
U4 transform;
};
// TODO(Ed): Bugged, fix
internal MipsAtom_(set_gte_world) {
/* Pop matrix address from tape into R_T3 ($11) */
load_word(R_T3, R_TapePtr, O_(Binds_SetGteWorld,transform)),
add_ui_self( R_TapePtr, S_(Binds_SetGteWorld)),
// TODO(Ed): Annotate magic offsets.
/* Load 3x3 Rotation + 3x1 Translation from R_T3 into GTE CONTROL Regs (ctc2) */
load_word(R_T0, R_T3, 0), load_word(R_T1, R_T3, 4),
gte_ct( R_T0, gte_cr_RT11), gte_ct( R_T1, gte_cr_RT12),
load_word(R_T0, R_T3, 8), load_word(R_T1, R_T3, 12), load_word(R_T2, R_T3, 16),
gte_ct( R_T0, gte_cr_RT13), gte_ct( R_T1, gte_cr_RT21), gte_ct( R_T2, gte_cr_RT22),
load_word(R_T0, R_T3, 20), load_word(R_T1, R_T3, 24), load_word(R_T2, R_T3, 28),
gte_ct( R_T0, gte_cr_TRX), gte_ct( R_T1, gte_cr_TRY), gte_ct( R_T2, gte_cr_TRZ),
mac_yield()
};
// TODO(Ed): I'm not sure yet if the bindings are redundant with the floortri atom yet.
/* DIAGNOSTIC 1: Pure tape loop test */
internal MipsAtom_(diag_yield) { mac_yield() };
// TODO(Ed): Reduce magic numbers/offsets
/* DIAGNOSTIC 2: Pure memory test (No GTE). Draws a fixed cyan triangle. */
internal MipsAtom_(diag_color) {
store_word( R_0, R_T7, 0),
load_upper_i(R_AT, gcmd_poly_f3 << 8 | 0xFF), /* High: MipsCode Poly_F3(0x20) + Color B:FF */
or_i( R_AT, R_AT, 0xFF00), /* Low: Color G:FF, R:00 (Cyan) */
store_word( R_AT, R_T7, 4),
/* Fake coordinates - Swapped winding order to prevent GPU culling! */
load_upper_i(R_AT, 0x0010), or_i(R_AT, R_AT, 0x0010), store_word(R_AT, R_T7, 8), /* (16, 16) */
load_upper_i(R_AT, 0x0050), or_i(R_AT, R_AT, 0x0010), store_word(R_AT, R_T7, 12), /* (80, 16) */
load_upper_i(R_AT, 0x0010), or_i(R_AT, R_AT, 0x0050), store_word(R_AT, R_T7, 16), /* (16, 80) */
add_ui( R_T1, R_0, 10),
shift_lleft(R_T1, R_T1, 2),
add_u( R_T1, R_T1, R_T6),
load_word( R_AT, R_T1, 0),
load_upper_i(R_V0, 0x0400), // <--- Fills load delay slot!
store_word( R_AT, R_T7, 0),
shift_lleft( R_AT, R_T7, 8), shift_lright(R_AT, R_AT, 8),
or_u( R_AT, R_AT, R_V0),
store_word(R_AT, R_T1, 0),
add_ui(R_T7, R_T7, 20),
mac_yield()
};
// TODO(Ed): Reduce magic numbers/offsets
/* DIAGNOSTIC 3: Pure GTE test (No Memory Writes) */
internal MipsAtom_(diag_gte) {
/* Load 3 indices */
load_half_u(R_T0, R_T4, 0),
load_half_u(R_T1, R_T4, 2),
load_half_u(R_T2, R_T4, 4),
/* Load Vertices into GTE */
shift_lleft( R_AT, R_T0, 3), add_u( R_AT, R_AT, R_T5),
load_word(R_V0, R_AT, 0), load_word(R_V1, R_AT, 4),
gte_mt( R_V0, C2_VXY0), gte_mt( R_V1, C2_VZ0),
shift_lleft( R_AT, R_T1, 3), add_u( R_AT, R_AT, R_T5),
load_word(R_V0, R_AT, 0), load_word(R_V1, R_AT, 4),
gte_mt( R_V0, C2_VXY1), gte_mt( R_V1, C2_VZ1),
shift_lleft( R_AT, R_T2, 3), add_u( R_AT, R_AT, R_T5),
load_word(R_V0, R_AT, 0), load_word(R_V1, R_AT, 4),
gte_mt( R_V0, C2_VXY2), gte_mt( R_V1, C2_VZ2),
/* Run Math */
nop, nop, gte_cmdw_rtpt,
nop, nop, gte_cmdw_nclip,
nop, nop,
/* Advance Face Cursor and Yield */
add_ui(R_T4, R_T4, 8),
mac_yield()
};
#pragma endregion Baked Mips Atoms