diff --git a/etc/mkuxn-fast.lua b/etc/mkuxn-fast.lua index 9a571a3..21c31b2 100644 --- a/etc/mkuxn-fast.lua +++ b/etc/mkuxn-fast.lua @@ -322,7 +322,6 @@ uxn_eval(Uxn *u, Uint16 vec) if(u->dev[0].dat[0xf]) return 0; u->ram.ptr = vec; - if(u->wst.ptr > 0xf8) u->wst.ptr = 0xf8; while(u->ram.ptr) { instr = u->ram.dat[u->ram.ptr++]; switch(instr) { diff --git a/etc/mkuxn-fast.moon b/etc/mkuxn-fast.moon index 4247bc5..c8ce667 100644 --- a/etc/mkuxn-fast.moon +++ b/etc/mkuxn-fast.moon @@ -231,7 +231,6 @@ uxn_eval(Uxn *u, Uint16 vec) if(u->dev[0].dat[0xf]) return 0; u->ram.ptr = vec; - if(u->wst.ptr > 0xf8) u->wst.ptr = 0xf8; while(u->ram.ptr) { instr = u->ram.dat[u->ram.ptr++]; switch(instr) { diff --git a/src/uxn-fast.c b/src/uxn-fast.c index 9b74de6..ca462d2 100644 --- a/src/uxn-fast.c +++ b/src/uxn-fast.c @@ -45,7 +45,6 @@ uxn_eval(Uxn *u, Uint16 vec) if(u->dev[0].dat[0xf]) return 0; u->ram.ptr = vec; - if(u->wst.ptr > 0xf8) u->wst.ptr = 0xf8; while(u->ram.ptr) { instr = u->ram.dat[u->ram.ptr++]; switch(instr) { diff --git a/src/uxn.c b/src/uxn.c index 8c09a52..8015b48 100644 --- a/src/uxn.c +++ b/src/uxn.c @@ -12,95 +12,98 @@ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE. */ +#define MODE_RETURN 0x40 +#define MODE_KEEP 0x80 + #pragma mark - Operations /* clang-format off */ -void push8(Stack *s, Uint8 a) { if(s->ptr == 0xff) { s->error = 2; return; } s->dat[s->ptr++] = a; } -Uint8 pop8_keep(Stack *s) { if(s->kptr == 0) { s->error = 1; return 0; } return s->dat[--s->kptr]; } -Uint8 pop8_nokeep(Stack *s) { if(s->ptr == 0) { s->error = 1; return 0; } return s->dat[--s->ptr]; } +static void push8(Stack *s, Uint8 a) { if(s->ptr == 0xff) { s->error = 2; return; } s->dat[s->ptr++] = a; } +static Uint8 pop8_keep(Stack *s) { if(s->kptr == 0) { s->error = 1; return 0; } return s->dat[--s->kptr]; } +static Uint8 pop8_nokeep(Stack *s) { if(s->ptr == 0) { s->error = 1; return 0; } return s->dat[--s->ptr]; } static Uint8 (*pop8)(Stack *s); -void mempoke8(Uint8 *m, Uint16 a, Uint8 b) { m[a] = b; } -Uint8 mempeek8(Uint8 *m, Uint16 a) { return m[a]; } -void devpoke8(Device *d, Uint8 a, Uint8 b) { d->dat[a & 0xf] = b; d->talk(d, a & 0x0f, 1); } -Uint8 devpeek8(Device *d, Uint8 a) { d->talk(d, a & 0x0f, 0); return d->dat[a & 0xf]; } -void push16(Stack *s, Uint16 a) { push8(s, a >> 8); push8(s, a); } -Uint16 pop16(Stack *s) { Uint8 a = pop8(s), b = pop8(s); return a + (b << 8); } +static void mempoke8(Uint8 *m, Uint16 a, Uint8 b) { m[a] = b; } +static Uint8 mempeek8(Uint8 *m, Uint16 a) { return m[a]; } +static void devpoke8(Device *d, Uint8 a, Uint8 b) { d->dat[a & 0xf] = b; d->talk(d, a & 0x0f, 1); } +static Uint8 devpeek8(Device *d, Uint8 a) { d->talk(d, a & 0x0f, 0); return d->dat[a & 0xf]; } +static void push16(Stack *s, Uint16 a) { push8(s, a >> 8); push8(s, a); } +static Uint16 pop16(Stack *s) { Uint8 a = pop8(s), b = pop8(s); return a + (b << 8); } void mempoke16(Uint8 *m, Uint16 a, Uint16 b) { mempoke8(m, a, b >> 8); mempoke8(m, a + 1, b); } Uint16 mempeek16(Uint8 *m, Uint16 a) { return (mempeek8(m, a) << 8) + mempeek8(m, a + 1); } -void devpoke16(Device *d, Uint8 a, Uint16 b) { devpoke8(d, a, b >> 8); devpoke8(d, a + 1, b); } -Uint16 devpeek16(Device *d, Uint16 a) { return (devpeek8(d, a) << 8) + devpeek8(d, a + 1); } +static void devpoke16(Device *d, Uint8 a, Uint16 b) { devpoke8(d, a, b >> 8); devpoke8(d, a + 1, b); } +static Uint16 devpeek16(Device *d, Uint16 a) { return (devpeek8(d, a) << 8) + devpeek8(d, a + 1); } /* Stack */ -void op_brk(Uxn *u) { u->ram.ptr = 0; } -void op_nop(Uxn *u) { (void)u; } -void op_lit(Uxn *u) { push8(u->src, mempeek8(u->ram.dat, u->ram.ptr++)); } -void op_pop(Uxn *u) { pop8(u->src); } -void op_dup(Uxn *u) { Uint8 a = pop8(u->src); push8(u->src, a); push8(u->src, a); } -void op_swp(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, a); push8(u->src, b); } -void op_ovr(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b); push8(u->src, a); push8(u->src, b); } -void op_rot(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src), c = pop8(u->src); push8(u->src, b); push8(u->src, a); push8(u->src, c); } +static void op_brk(Uxn *u) { u->ram.ptr = 0; } +static void op_nop(Uxn *u) { (void)u; } +static void op_lit(Uxn *u) { push8(u->src, mempeek8(u->ram.dat, u->ram.ptr++)); } +static void op_pop(Uxn *u) { pop8(u->src); } +static void op_dup(Uxn *u) { Uint8 a = pop8(u->src); push8(u->src, a); push8(u->src, a); } +static void op_swp(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, a); push8(u->src, b); } +static void op_ovr(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b); push8(u->src, a); push8(u->src, b); } +static void op_rot(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src), c = pop8(u->src); push8(u->src, b); push8(u->src, a); push8(u->src, c); } /* Logic */ -void op_equ(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b == a); } -void op_neq(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b != a); } -void op_gth(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b > a); } -void op_lth(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b < a); } -void op_jmp(Uxn *u) { Uint8 a = pop8(u->src); u->ram.ptr += (Sint8)a; } -void op_jnz(Uxn *u) { Uint8 a = pop8(u->src); if(pop8(u->src)) u->ram.ptr += (Sint8)a; } -void op_jsr(Uxn *u) { Uint8 a = pop8(u->src); push16(u->dst, u->ram.ptr); u->ram.ptr += (Sint8)a; } -void op_sth(Uxn *u) { Uint8 a = pop8(u->src); push8(u->dst, a); } +static void op_equ(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b == a); } +static void op_neq(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b != a); } +static void op_gth(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b > a); } +static void op_lth(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b < a); } +static void op_jmp(Uxn *u) { Uint8 a = pop8(u->src); u->ram.ptr += (Sint8)a; } +static void op_jnz(Uxn *u) { Uint8 a = pop8(u->src); if(pop8(u->src)) u->ram.ptr += (Sint8)a; } +static void op_jsr(Uxn *u) { Uint8 a = pop8(u->src); push16(u->dst, u->ram.ptr); u->ram.ptr += (Sint8)a; } +static void op_sth(Uxn *u) { Uint8 a = pop8(u->src); push8(u->dst, a); } /* Memory */ -void op_pek(Uxn *u) { Uint8 a = pop8(u->src); push8(u->src, mempeek8(u->ram.dat, a)); } -void op_pok(Uxn *u) { Uint8 a = pop8(u->src); Uint8 b = pop8(u->src); mempoke8(u->ram.dat, a, b); } -void op_ldr(Uxn *u) { Uint8 a = pop8(u->src); push8(u->src, mempeek8(u->ram.dat, u->ram.ptr + (Sint8)a)); } -void op_str(Uxn *u) { Uint8 a = pop8(u->src); Uint8 b = pop8(u->src); mempoke8(u->ram.dat, u->ram.ptr + (Sint8)a, b); } -void op_lda(Uxn *u) { Uint16 a = pop16(u->src); push8(u->src, mempeek8(u->ram.dat, a)); } -void op_sta(Uxn *u) { Uint16 a = pop16(u->src); Uint8 b = pop8(u->src); mempoke8(u->ram.dat, a, b); } -void op_dei(Uxn *u) { Uint8 a = pop8(u->src); push8(u->src, devpeek8(&u->dev[a >> 4], a)); } -void op_deo(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); devpoke8(&u->dev[a >> 4], a, b); } +static void op_pek(Uxn *u) { Uint8 a = pop8(u->src); push8(u->src, mempeek8(u->ram.dat, a)); } +static void op_pok(Uxn *u) { Uint8 a = pop8(u->src); Uint8 b = pop8(u->src); mempoke8(u->ram.dat, a, b); } +static void op_ldr(Uxn *u) { Uint8 a = pop8(u->src); push8(u->src, mempeek8(u->ram.dat, u->ram.ptr + (Sint8)a)); } +static void op_str(Uxn *u) { Uint8 a = pop8(u->src); Uint8 b = pop8(u->src); mempoke8(u->ram.dat, u->ram.ptr + (Sint8)a, b); } +static void op_lda(Uxn *u) { Uint16 a = pop16(u->src); push8(u->src, mempeek8(u->ram.dat, a)); } +static void op_sta(Uxn *u) { Uint16 a = pop16(u->src); Uint8 b = pop8(u->src); mempoke8(u->ram.dat, a, b); } +static void op_dei(Uxn *u) { Uint8 a = pop8(u->src); push8(u->src, devpeek8(&u->dev[a >> 4], a)); } +static void op_deo(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); devpoke8(&u->dev[a >> 4], a, b); } /* Arithmetic */ -void op_add(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b + a); } -void op_sub(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b - a); } -void op_mul(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b * a); } -void op_div(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); if(a == 0) { u->src->error = 3; a = 1; } push8(u->src, b / a); } -void op_and(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b & a); } -void op_ora(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b | a); } -void op_eor(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b ^ a); } -void op_sft(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b >> (a & 0x07) << ((a & 0x70) >> 4)); } +static void op_add(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b + a); } +static void op_sub(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b - a); } +static void op_mul(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b * a); } +static void op_div(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); if(a == 0) { u->src->error = 3; a = 1; } push8(u->src, b / a); } +static void op_and(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b & a); } +static void op_ora(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b | a); } +static void op_eor(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b ^ a); } +static void op_sft(Uxn *u) { Uint8 a = pop8(u->src), b = pop8(u->src); push8(u->src, b >> (a & 0x07) << ((a & 0x70) >> 4)); } /* Stack */ -void op_lit16(Uxn *u) { push16(u->src, mempeek16(u->ram.dat, u->ram.ptr++)); u->ram.ptr++; } -void op_pop16(Uxn *u) { pop16(u->src); } -void op_dup16(Uxn *u) { Uint16 a = pop16(u->src); push16(u->src, a); push16(u->src, a); } -void op_swp16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, a); push16(u->src, b); } -void op_ovr16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b); push16(u->src, a); push16(u->src, b); } -void op_rot16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src), c = pop16(u->src); push16(u->src, b); push16(u->src, a); push16(u->src, c); } +static void op_lit16(Uxn *u) { push16(u->src, mempeek16(u->ram.dat, u->ram.ptr++)); u->ram.ptr++; } +static void op_pop16(Uxn *u) { pop16(u->src); } +static void op_dup16(Uxn *u) { Uint16 a = pop16(u->src); push16(u->src, a); push16(u->src, a); } +static void op_swp16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, a); push16(u->src, b); } +static void op_ovr16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b); push16(u->src, a); push16(u->src, b); } +static void op_rot16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src), c = pop16(u->src); push16(u->src, b); push16(u->src, a); push16(u->src, c); } /* Logic(16-bits) */ -void op_equ16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push8(u->src, b == a); } -void op_neq16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push8(u->src, b != a); } -void op_gth16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push8(u->src, b > a); } -void op_lth16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push8(u->src, b < a); } -void op_jmp16(Uxn *u) { u->ram.ptr = pop16(u->src); } -void op_jnz16(Uxn *u) { Uint16 a = pop16(u->src); if(pop8(u->src)) u->ram.ptr = a; } -void op_jsr16(Uxn *u) { push16(u->dst, u->ram.ptr); u->ram.ptr = pop16(u->src); } -void op_sth16(Uxn *u) { Uint16 a = pop16(u->src); push16(u->dst, a); } +static void op_equ16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push8(u->src, b == a); } +static void op_neq16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push8(u->src, b != a); } +static void op_gth16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push8(u->src, b > a); } +static void op_lth16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push8(u->src, b < a); } +static void op_jmp16(Uxn *u) { u->ram.ptr = pop16(u->src); } +static void op_jnz16(Uxn *u) { Uint16 a = pop16(u->src); if(pop8(u->src)) u->ram.ptr = a; } +static void op_jsr16(Uxn *u) { push16(u->dst, u->ram.ptr); u->ram.ptr = pop16(u->src); } +static void op_sth16(Uxn *u) { Uint16 a = pop16(u->src); push16(u->dst, a); } /* Memory(16-bits) */ -void op_pek16(Uxn *u) { Uint8 a = pop8(u->src); push16(u->src, mempeek16(u->ram.dat, a)); } -void op_pok16(Uxn *u) { Uint8 a = pop8(u->src); Uint16 b = pop16(u->src); mempoke16(u->ram.dat, a, b); } -void op_ldr16(Uxn *u) { Uint8 a = pop8(u->src); push16(u->src, mempeek16(u->ram.dat, u->ram.ptr + (Sint8)a)); } -void op_str16(Uxn *u) { Uint8 a = pop8(u->src); Uint16 b = pop16(u->src); mempoke16(u->ram.dat, u->ram.ptr + (Sint8)a, b); } -void op_lda16(Uxn *u) { Uint16 a = pop16(u->src); push16(u->src, mempeek16(u->ram.dat, a)); } -void op_sta16(Uxn *u) { Uint16 a = pop16(u->src); Uint16 b = pop16(u->src); mempoke16(u->ram.dat, a, b); } -void op_dei16(Uxn *u) { Uint8 a = pop8(u->src); push16(u->src, devpeek16(&u->dev[a >> 4], a)); } -void op_deo16(Uxn *u) { Uint8 a = pop8(u->src); Uint16 b = pop16(u->src); devpoke16(&u->dev[a >> 4], a, b); } +static void op_pek16(Uxn *u) { Uint8 a = pop8(u->src); push16(u->src, mempeek16(u->ram.dat, a)); } +static void op_pok16(Uxn *u) { Uint8 a = pop8(u->src); Uint16 b = pop16(u->src); mempoke16(u->ram.dat, a, b); } +static void op_ldr16(Uxn *u) { Uint8 a = pop8(u->src); push16(u->src, mempeek16(u->ram.dat, u->ram.ptr + (Sint8)a)); } +static void op_str16(Uxn *u) { Uint8 a = pop8(u->src); Uint16 b = pop16(u->src); mempoke16(u->ram.dat, u->ram.ptr + (Sint8)a, b); } +static void op_lda16(Uxn *u) { Uint16 a = pop16(u->src); push16(u->src, mempeek16(u->ram.dat, a)); } +static void op_sta16(Uxn *u) { Uint16 a = pop16(u->src); Uint16 b = pop16(u->src); mempoke16(u->ram.dat, a, b); } +static void op_dei16(Uxn *u) { Uint8 a = pop8(u->src); push16(u->src, devpeek16(&u->dev[a >> 4], a)); } +static void op_deo16(Uxn *u) { Uint8 a = pop8(u->src); Uint16 b = pop16(u->src); devpoke16(&u->dev[a >> 4], a, b); } /* Arithmetic(16-bits) */ -void op_add16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b + a); } -void op_sub16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b - a); } -void op_mul16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b * a); } -void op_div16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); if(a == 0) { u->src->error = 3; a = 1; } push16(u->src, b / a); } -void op_and16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b & a); } -void op_ora16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b | a); } -void op_eor16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b ^ a); } -void op_sft16(Uxn *u) { Uint8 a = pop8(u->src); Uint16 b = pop16(u->src); push16(u->src, b >> (a & 0x0f) << ((a & 0xf0) >> 4)); } +static void op_add16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b + a); } +static void op_sub16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b - a); } +static void op_mul16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b * a); } +static void op_div16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); if(a == 0) { u->src->error = 3; a = 1; } push16(u->src, b / a); } +static void op_and16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b & a); } +static void op_ora16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b | a); } +static void op_eor16(Uxn *u) { Uint16 a = pop16(u->src), b = pop16(u->src); push16(u->src, b ^ a); } +static void op_sft16(Uxn *u) { Uint8 a = pop8(u->src); Uint16 b = pop16(u->src); push16(u->src, b >> (a & 0x0f) << ((a & 0xf0) >> 4)); } -void (*ops[])(Uxn *u) = { +static void (*ops[])(Uxn *u) = { op_brk, op_lit, op_nop, op_pop, op_dup, op_swp, op_ovr, op_rot, op_equ, op_neq, op_gth, op_lth, op_jmp, op_jnz, op_jsr, op_sth, op_pek, op_pok, op_ldr, op_str, op_lda, op_sta, op_dei, op_deo, @@ -116,38 +119,35 @@ void (*ops[])(Uxn *u) = { #pragma mark - Core -int -uxn_step(Uxn *u, Uint8 instr) -{ - Uint8 op = instr & 0x3f, freturn = instr & 0x40, fkeep = instr & 0x80; - u->src = freturn ? &u->rst : &u->wst; - u->dst = freturn ? &u->wst : &u->rst; - if(fkeep) { - pop8 = pop8_keep; - u->src->kptr = u->src->ptr; - } else - pop8 = pop8_nokeep; - /* run */ - (*ops[op])(u); - if(u->wst.error) - return uxn_halt(u, u->wst.error, "Working-stack", instr); - if(u->rst.error) - return uxn_halt(u, u->rst.error, "Return-stack", instr); - return 1; -} - int uxn_eval(Uxn *u, Uint16 vec) { if(u->dev[0].dat[0xf]) return 0; u->ram.ptr = vec; - u->wst.error = 0; - u->rst.error = 0; - if(u->wst.ptr > 0xf8) u->wst.ptr = 0xf8; - while(u->ram.ptr) - if(!uxn_step(u, u->ram.dat[u->ram.ptr++])) - return 0; + while(u->ram.ptr) { + Uint8 instr = u->ram.dat[u->ram.ptr++]; + /* Return Mode */ + if(instr & MODE_RETURN) { + u->src = &u->rst; + u->dst = &u->wst; + } else { + u->src = &u->wst; + u->dst = &u->rst; + } + /* Keep Mode */ + if(instr & MODE_KEEP) { + pop8 = pop8_keep; + u->src->kptr = u->src->ptr; + } else { + pop8 = pop8_nokeep; + } + (*ops[instr & 0x3f])(u); + if(u->wst.error) + return uxn_halt(u, u->wst.error, "Working-stack", instr); + if(u->rst.error) + return uxn_halt(u, u->rst.error, "Return-stack", instr); + } return 1; }