Using new core

This commit is contained in:
Devine Lu Linvega 2023-04-30 11:43:33 -07:00
parent cb1fe32792
commit 87a72de69e
4 changed files with 254 additions and 68 deletions

101
etc/archive/uxn.c Normal file
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#include "uxn.h"
#include <stdio.h>
/*
Copyright (u) 2022-2023 Devine Lu Linvega, Andrew Alderwick, Andrew Richards
Permission to use, copy, modify, and distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE.
*/
/* a,b,c: general use. m2: byte/short mode flag.
tsp: macro temp stack ptr. ksp: "keep" mode copy of stack ptr. sp: ptr to stack ptr.
x,y: macro in params. o: macro out param. */
#define HALT(c) { return uxn_halt(u, instr, (c), pc - 1); }
#define JUMP(x) { if(m2) pc = (x); else pc += (Sint8)(x); }
#define PUSH8(x) { if(s->ptr == 0xff) HALT(2) s->dat[s->ptr++] = (x); }
#define PUSH16(x) { if((tsp = s->ptr) >= 0xfe) HALT(2) t = (x); s->dat[tsp] = t >> 8; s->dat[tsp + 1] = t; s->ptr = tsp + 2; }
#define PUSH(x) { if(m2) { PUSH16(x) } else { PUSH8(x) } }
#define POP8(o) { if(*sp == 0x00) HALT(1) o = s->dat[--*sp]; }
#define POP16(o) { if((tsp = *sp) <= 0x01) HALT(1) o = s->dat[tsp - 1] | (s->dat[tsp - 2] << 8); *sp = tsp - 2; }
#define POP(o) { if(m2) { POP16(o) } else { POP8(o) } }
#define POKE(x, y) { if(m2) { t = (y); u->ram[(x)] = t >> 8; u->ram[(x) + 1] = t; } else { u->ram[(x)] = (y); } }
#define PEEK16(o, x) { o = (u->ram[(x)] << 8) | u->ram[(x) + 1]; }
#define PEEK(o, x) { if(m2) PEEK16(o, x) else o = u->ram[(x)]; }
#define DEO(a, b) { u->dev[(a)] = (b); if((deo_mask[(a) >> 4] >> ((a) & 0xf)) & 0x1) uxn_deo(u, (a)); }
#define DEI(a, b) { a = ((dei_mask[(b) >> 4] >> ((b) & 0xf)) & 0x1) ? uxn_dei(u, (b)) : u->dev[(b)]; }
int
uxn_eval(Uxn *u, Uint16 pc)
{
Uint8 instr, opcode, m2, ksp, tsp, *sp;
Uint16 a, b, c, t;
Stack *s;
if(!pc || u->dev[0x0f]) return 0;
for(;;) {
instr = u->ram[pc++];
opcode = instr & 0x1f;
/* 2 Mode */ m2 = instr & 0x20;
/* r Mode */ s = instr & 0x40 ? &u->rst : &u->wst;
/* k Mode */ if(instr & 0x80) { ksp = s->ptr; sp = &ksp; } else sp = &s->ptr;
switch(opcode - (!opcode * (instr >> 5))) {
/* Immediate */
case -0x0: /* BRK */ return 1;
case -0x1: /* JCI */ POP8(b) if(!b) { pc += 2; break; } /* fall through */
case -0x2: /* JMI */ PEEK16(a, pc) pc += a + 2; break;
case -0x3: /* JSI */ s = &u->rst; PUSH16(pc + 2) PEEK16(a, pc) pc += a + 2; break;
case -0x4: /* LIT */
case -0x6: /* LITr */ a = u->ram[pc++]; PUSH8(a) break;
case -0x5: /* LIT2 */
case -0x7: /* LIT2r */ PEEK16(a, pc) PUSH16(a) pc += 2; break;
/* ALU */
case 0x01: /* INC */ POP(a) PUSH(a + 1) break;
case 0x02: /* POP */ POP(a) break;
case 0x03: /* NIP */ POP(a) POP(b) PUSH(a) break;
case 0x04: /* SWP */ POP(a) POP(b) PUSH(a) PUSH(b) break;
case 0x05: /* ROT */ POP(a) POP(b) POP(c) PUSH(b) PUSH(a) PUSH(c) break;
case 0x06: /* DUP */ POP(a) PUSH(a) PUSH(a) break;
case 0x07: /* OVR */ POP(a) POP(b) PUSH(b) PUSH(a) PUSH(b) break;
case 0x08: /* EQU */ POP(a) POP(b) PUSH8(b == a) break;
case 0x09: /* NEQ */ POP(a) POP(b) PUSH8(b != a) break;
case 0x0a: /* GTH */ POP(a) POP(b) PUSH8(b > a) break;
case 0x0b: /* LTH */ POP(a) POP(b) PUSH8(b < a) break;
case 0x0c: /* JMP */ POP(a) JUMP(a) break;
case 0x0d: /* JCN */ POP(a) POP8(b) if(b) JUMP(a) break;
case 0x0e: /* JSR */ POP(a) s = (instr & 0x40) ? &u->wst : &u->rst; PUSH16(pc) JUMP(a) break;
case 0x0f: /* STH */ POP(a) s = (instr & 0x40) ? &u->wst : &u->rst; PUSH(a) break;
case 0x10: /* LDZ */ POP8(a) PEEK(b, a) PUSH(b) break;
case 0x11: /* STZ */ POP8(a) POP(b) POKE(a, b) break;
case 0x12: /* LDR */ POP8(a) PEEK(b, pc + (Sint8)a) PUSH(b) break;
case 0x13: /* STR */ POP8(a) POP(b) POKE(pc + (Sint8)a, b) break;
case 0x14: /* LDA */ POP16(a) PEEK(b, a) PUSH(b) break;
case 0x15: /* STA */ POP16(a) POP(b) POKE(a, b) break;
case 0x16: /* DEI */ POP8(a) if(m2){ DEI(b, a) DEI(c, a + 1) PUSH16((b << 8) | c) } else { DEI(b, a) PUSH8(b) } break;
case 0x17: /* DEO */ POP8(a) if(m2){ POP(b) DEO(a, b >> 8) DEO(a + 1, b) } else { POP8(b) DEO(a, b) } break;
case 0x18: /* ADD */ POP(a) POP(b) PUSH(b + a) break;
case 0x19: /* SUB */ POP(a) POP(b) PUSH(b - a) break;
case 0x1a: /* MUL */ POP(a) POP(b) PUSH((Uint32)b * a) break;
case 0x1b: /* DIV */ POP(a) POP(b) if(!a) HALT(3) PUSH(b / a) break;
case 0x1c: /* AND */ POP(a) POP(b) PUSH(b & a) break;
case 0x1d: /* ORA */ POP(a) POP(b) PUSH(b | a) break;
case 0x1e: /* EOR */ POP(a) POP(b) PUSH(b ^ a) break;
case 0x1f: /* SFT */ POP8(a) POP(b) PUSH(b >> (a & 0x0f) << ((a & 0xf0) >> 4)) break;
}
}
}
int
uxn_boot(Uxn *u, Uint8 *ram)
{
Uint32 i;
char *cptr = (char *)u;
for(i = 0; i < sizeof(*u); i++)
cptr[i] = 0;
u->ram = ram;
return 1;
}

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etc/archive/uxn.h Normal file
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/*
Copyright (c) 2021 Devine Lu Linvega
Permission to use, copy, modify, and distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE.
*/
#define PAGE_PROGRAM 0x0100
/* clang-format off */
#define POKE2(d, v) { (d)[0] = (v) >> 8; (d)[1] = (v); }
#define PEEK2(d) ((d)[0] << 8 | (d)[1])
/* clang-format on */
typedef unsigned char Uint8;
typedef signed char Sint8;
typedef unsigned short Uint16;
typedef signed short Sint16;
typedef unsigned int Uint32;
typedef struct {
Uint8 dat[255], ptr;
} Stack;
typedef struct Uxn {
Uint8 *ram, dev[256];
Stack wst, rst;
Uint8 (*dei)(struct Uxn *u, Uint8 addr);
void (*deo)(struct Uxn *u, Uint8 addr);
} Uxn;
/* required functions */
extern Uint8 uxn_dei(Uxn *u, Uint8 addr);
extern void uxn_deo(Uxn *u, Uint8 addr);
extern int uxn_halt(Uxn *u, Uint8 instr, Uint8 err, Uint16 addr);
extern Uint16 dei_mask[];
extern Uint16 deo_mask[];
/* built-ins */
int uxn_boot(Uxn *u, Uint8 *ram);
int uxn_eval(Uxn *u, Uint16 pc);

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src/uxn.c
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#include "uxn.h"
#include <stdio.h>
/*
Copyright (u) 2022-2023 Devine Lu Linvega, Andrew Alderwick, Andrew Richards
@ -12,79 +11,116 @@ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE.
*/
/* a,b,c: general use. m2: byte/short mode flag.
tsp: macro temp stack ptr. ksp: "keep" mode copy of stack ptr. sp: ptr to stack ptr.
x,y: macro in params. o: macro out param. */
#define T s->dat[s->ptr - 1]
#define N s->dat[s->ptr - 2]
#define L s->dat[s->ptr - 3]
#define H2 PEEK2(s->dat + s->ptr - 3)
#define T2 PEEK2(s->dat + s->ptr - 2)
#define N2 PEEK2(s->dat + s->ptr - 4)
#define L2 PEEK2(s->dat + s->ptr - 6)
#define HALT(c) { return uxn_halt(u, instr, (c), pc - 1); }
#define JUMP(x) { if(m2) pc = (x); else pc += (Sint8)(x); }
#define PUSH8(x) { if(s->ptr == 0xff) HALT(2) s->dat[s->ptr++] = (x); }
#define PUSH16(x) { if((tsp = s->ptr) >= 0xfe) HALT(2) t = (x); s->dat[tsp] = t >> 8; s->dat[tsp + 1] = t; s->ptr = tsp + 2; }
#define PUSH(x) { if(m2) { PUSH16(x) } else { PUSH8(x) } }
#define POP8(o) { if(*sp == 0x00) HALT(1) o = s->dat[--*sp]; }
#define POP16(o) { if((tsp = *sp) <= 0x01) HALT(1) o = s->dat[tsp - 1] | (s->dat[tsp - 2] << 8); *sp = tsp - 2; }
#define POP(o) { if(m2) { POP16(o) } else { POP8(o) } }
#define POKE(x, y) { if(m2) { t = (y); u->ram[(x)] = t >> 8; u->ram[(x) + 1] = t; } else { u->ram[(x)] = (y); } }
#define PEEK16(o, x) { o = (u->ram[(x)] << 8) | u->ram[(x) + 1]; }
#define PEEK(o, x) { if(m2) PEEK16(o, x) else o = u->ram[(x)]; }
/* Registers
[ . ][ . ][ . ][ L ][ N ][ T ] <
[ . ][ . ][ . ][ H2 ][ T ] <
[ L2 ][ N2 ][ T2 ] <
*/
#define HALT(c) { return uxn_halt(u, ins, (c), pc - 1); }
#define SET(mul, add) { if(mul > s->ptr) HALT(1) tmp = s->ptr + k * mul + add; if(tmp > 254) HALT(2) s->ptr = tmp; }
#define PUT(o, v) { s->dat[(Uint8)(s->ptr - 1 - (o))] = (v); }
#define PUT2(o, v) { tmp = (v); s->dat[(Uint8)(s->ptr - o - 2)] = tmp >> 8; s->dat[(Uint8)(s->ptr - o - 1)] = tmp; }
#define PUSH(x, v) { z = (x); if(z->ptr > 254) HALT(2) z->dat[z->ptr++] = (v); }
#define PUSH2(x, v) { z = (x); if(z->ptr > 253) HALT(2) tmp = (v); z->dat[z->ptr] = tmp >> 8; z->dat[z->ptr + 1] = tmp; z->ptr += 2; }
#define DEO(a, b) { u->dev[(a)] = (b); if((deo_mask[(a) >> 4] >> ((a) & 0xf)) & 0x1) uxn_deo(u, (a)); }
#define DEI(a, b) { a = ((dei_mask[(b) >> 4] >> ((b) & 0xf)) & 0x1) ? uxn_dei(u, (b)) : u->dev[(b)]; }
#define DEI(a, b) { PUT((a), ((dei_mask[(b) >> 4] >> ((b) & 0xf)) & 0x1) ? uxn_dei(u, (b)) : u->dev[(b)]) }
int
uxn_eval(Uxn *u, Uint16 pc)
{
Uint8 instr, opcode, m2, ksp, tsp, *sp;
Uint16 a, b, c, t;
Stack *s;
int t, n, l, k, tmp, opc, ins;
Uint8 *ram = u->ram;
Stack *s, *z;
if(!pc || u->dev[0x0f]) return 0;
for(;;) {
instr = u->ram[pc++];
opcode = instr & 0x1f;
/* 2 Mode */ m2 = instr & 0x20;
/* r Mode */ s = instr & 0x40 ? &u->rst : &u->wst;
/* k Mode */ if(instr & 0x80) { ksp = s->ptr; sp = &ksp; } else sp = &s->ptr;
switch(opcode - (!opcode * (instr >> 5))) {
/* Immediate */
case -0x0: /* BRK */ return 1;
case -0x1: /* JCI */ POP8(b) if(!b) { pc += 2; break; } /* fall through */
case -0x2: /* JMI */ PEEK16(a, pc) pc += a + 2; break;
case -0x3: /* JSI */ s = &u->rst; PUSH16(pc + 2) PEEK16(a, pc) pc += a + 2; break;
case -0x4: /* LIT */
case -0x6: /* LITr */ a = u->ram[pc++]; PUSH8(a) break;
case -0x5: /* LIT2 */
case -0x7: /* LIT2r */ PEEK16(a, pc) PUSH16(a) pc += 2; break;
/* ALU */
case 0x01: /* INC */ POP(a) PUSH(a + 1) break;
case 0x02: /* POP */ POP(a) break;
case 0x03: /* NIP */ POP(a) POP(b) PUSH(a) break;
case 0x04: /* SWP */ POP(a) POP(b) PUSH(a) PUSH(b) break;
case 0x05: /* ROT */ POP(a) POP(b) POP(c) PUSH(b) PUSH(a) PUSH(c) break;
case 0x06: /* DUP */ POP(a) PUSH(a) PUSH(a) break;
case 0x07: /* OVR */ POP(a) POP(b) PUSH(b) PUSH(a) PUSH(b) break;
case 0x08: /* EQU */ POP(a) POP(b) PUSH8(b == a) break;
case 0x09: /* NEQ */ POP(a) POP(b) PUSH8(b != a) break;
case 0x0a: /* GTH */ POP(a) POP(b) PUSH8(b > a) break;
case 0x0b: /* LTH */ POP(a) POP(b) PUSH8(b < a) break;
case 0x0c: /* JMP */ POP(a) JUMP(a) break;
case 0x0d: /* JCN */ POP(a) POP8(b) if(b) JUMP(a) break;
case 0x0e: /* JSR */ POP(a) s = (instr & 0x40) ? &u->wst : &u->rst; PUSH16(pc) JUMP(a) break;
case 0x0f: /* STH */ POP(a) s = (instr & 0x40) ? &u->wst : &u->rst; PUSH(a) break;
case 0x10: /* LDZ */ POP8(a) PEEK(b, a) PUSH(b) break;
case 0x11: /* STZ */ POP8(a) POP(b) POKE(a, b) break;
case 0x12: /* LDR */ POP8(a) PEEK(b, pc + (Sint8)a) PUSH(b) break;
case 0x13: /* STR */ POP8(a) POP(b) POKE(pc + (Sint8)a, b) break;
case 0x14: /* LDA */ POP16(a) PEEK(b, a) PUSH(b) break;
case 0x15: /* STA */ POP16(a) POP(b) POKE(a, b) break;
case 0x16: /* DEI */ POP8(a) if(m2){ DEI(b, a) DEI(c, a + 1) PUSH16((b << 8) | c) } else { DEI(b, a) PUSH8(b) } break;
case 0x17: /* DEO */ POP8(a) if(m2){ POP(b) DEO(a, b >> 8) DEO(a + 1, b) } else { POP8(b) DEO(a, b) } break;
case 0x18: /* ADD */ POP(a) POP(b) PUSH(b + a) break;
case 0x19: /* SUB */ POP(a) POP(b) PUSH(b - a) break;
case 0x1a: /* MUL */ POP(a) POP(b) PUSH((Uint32)b * a) break;
case 0x1b: /* DIV */ POP(a) POP(b) if(!a) HALT(3) PUSH(b / a) break;
case 0x1c: /* AND */ POP(a) POP(b) PUSH(b & a) break;
case 0x1d: /* ORA */ POP(a) POP(b) PUSH(b | a) break;
case 0x1e: /* EOR */ POP(a) POP(b) PUSH(b ^ a) break;
case 0x1f: /* SFT */ POP8(a) POP(b) PUSH(b >> (a & 0x0f) << ((a & 0xf0) >> 4)) break;
ins = ram[pc++] & 0xff;
k = !!(ins & 0x80);
s = ins & 0x40 ? &u->rst : &u->wst;
opc = !(ins & 0x1f) ? (0 - (ins >> 5)) & 0xff : ins & 0x3f;
switch(opc) {
/* IMM */
case 0x00: /* BRK */ return 1;
case 0xff: /* JCI */ pc += !!s->dat[--s->ptr] * PEEK2(ram + pc) + 2; break;
case 0xfe: /* JMI */ pc += PEEK2(ram + pc) + 2; break;
case 0xfd: /* JSI */ PUSH2(&u->rst, pc + 2) pc += PEEK2(ram + pc) + 2; break;
case 0xfc: /* LIT */ PUSH(s, ram[pc++]) break;
case 0xfb: /* LIT2 */ PUSH2(s, PEEK2(ram + pc)) pc += 2; break;
case 0xfa: /* LITr */ PUSH(s, ram[pc++]) break;
case 0xf9: /* LIT2r */ PUSH2(s, PEEK2(ram + pc)) pc += 2; break;
/* ALU */
case 0x01: /* INC */ t=T; SET(1, 0) PUT(0, t + 1) break;
case 0x21: t=T2; SET(2, 0) PUT2(0, t + 1) break;
case 0x02: /* POP */ SET(1,-1) break;
case 0x22: SET(2,-2) break;
case 0x03: /* NIP */ t=T; SET(2,-1) PUT(0, t) break;
case 0x23: t=T2; SET(4,-2) PUT2(0, t) break;
case 0x04: /* SWP */ t=T;n=N; SET(2, 0) PUT(0, n) PUT(1, t) break;
case 0x24: t=T2;n=N2; SET(4, 0) PUT2(0, n) PUT2(2, t) break;
case 0x05: /* ROT */ t=T;n=N;l=L; SET(3, 0) PUT(0, l) PUT(1, t) PUT(2, n) break;
case 0x25: t=T2;n=N2;l=L2; SET(6, 0) PUT2(0, l) PUT2(2, t) PUT2(4, n) break;
case 0x06: /* DUP */ t=T; SET(1, 1) PUT(0, t) PUT(1, t) break;
case 0x26: t=T2; SET(2, 2) PUT2(0, t) PUT2(2, t) break;
case 0x07: /* OVR */ t=T;n=N; SET(2, 1) PUT(0, n) PUT(1, t) PUT(2, n) break;
case 0x27: t=T2;n=N2; SET(4, 2) PUT2(0, n) PUT2(2, t) PUT2(4, n) break;
case 0x08: /* EQU */ t=T;n=N; SET(2,-1) PUT(0, n == t) break;
case 0x28: t=T2;n=N2; SET(4,-3) PUT(0, n == t) break;
case 0x09: /* NEQ */ t=T;n=N; SET(2,-1) PUT(0, n != t) break;
case 0x29: t=T2;n=N2; SET(4,-3) PUT(0, n != t) break;
case 0x0a: /* GTH */ t=T;n=N; SET(2,-1) PUT(0, n > t) break;
case 0x2a: t=T2;n=N2; SET(4,-3) PUT(0, n > t) break;
case 0x0b: /* LTH */ t=T;n=N; SET(2,-1) PUT(0, n < t) break;
case 0x2b: t=T2;n=N2; SET(4,-3) PUT(0, n < t) break;
case 0x0c: /* JMP */ t=T; SET(1,-1) pc += (Sint8)t; break;
case 0x2c: t=T2; SET(2,-2) pc = t; break;
case 0x0d: /* JCN */ t=T;n=N; SET(2,-2) pc += !!n * (Sint8)t; break;
case 0x2d: t=T2;n=L; SET(3,-3) if(n) pc = t; break;
case 0x0e: /* JSR */ t=T; SET(1,-1) PUSH2(&u->rst, pc) pc += (Sint8)t; break;
case 0x2e: t=T2; SET(2,-2) PUSH2(&u->rst, pc) pc = t; break;
case 0x0f: /* STH */ t=T; SET(1,-1) PUSH((ins & 0x40 ? &u->wst : &u->rst), t) break;
case 0x2f: t=T2; SET(2,-2) PUSH2((ins & 0x40 ? &u->wst : &u->rst), t) break;
case 0x10: /* LDZ */ t=T; SET(1, 0) PUT(0, ram[t]) break;
case 0x30: t=T; SET(1, 1) PUT2(0, PEEK2(ram + t)) break;
case 0x11: /* STZ */ t=T;n=N; SET(2,-2) ram[t] = n; break;
case 0x31: t=T;n=H2; SET(3,-3) POKE2(ram + t, n) break;
case 0x12: /* LDR */ t=T; SET(1, 0) PUT(0, ram[pc + (Sint8)t]) break;
case 0x32: t=T; SET(1, 1) PUT2(0, PEEK2(ram + pc + (Sint8)t)) break;
case 0x13: /* STR */ t=T;n=N; SET(2,-2) ram[pc + (Sint8)t] = n; break;
case 0x33: t=T;n=H2; SET(3,-3) POKE2(ram + pc + (Sint8)t, n) break;
case 0x14: /* LDA */ t=T2; SET(2,-1) PUT(0, ram[t]) break;
case 0x34: t=T2; SET(2, 0) PUT2(0, PEEK2(ram + t)) break;
case 0x15: /* STA */ t=T2;n=L; SET(3,-3) ram[t] = n; break;
case 0x35: t=T2;n=N2; SET(4,-4) POKE2(ram + t, n) break;
case 0x16: /* DEI */ t=T; SET(1, 0) DEI(0, t) break;
case 0x36: t=T; SET(1, 1) DEI(1, t) DEI(0, t + 1) break;
case 0x17: /* DEO */ t=T;n=N; SET(2,-2) DEO(t, n) break;
case 0x37: t=T;n=N;l=L; SET(3,-3) DEO(t, l) DEO(t + 1, n) break;
case 0x18: /* ADD */ t=T;n=N; SET(2,-1) PUT(0, n + t) break;
case 0x38: t=T2;n=N2; SET(4,-2) PUT2(0, n + t) break;
case 0x19: /* SUB */ t=T;n=N; SET(2,-1) PUT(0, n - t) break;
case 0x39: t=T2;n=N2; SET(4,-2) PUT2(0, n - t) break;
case 0x1a: /* MUL */ t=T;n=N; SET(2,-1) PUT(0, n * t) break;
case 0x3a: t=T2;n=N2; SET(4,-2) PUT2(0, n * t) break;
case 0x1b: /* DIV */ t=T;n=N; SET(2,-1) if(!t) HALT(3) PUT(0, n / t) break;
case 0x3b: t=T2;n=N2; SET(4,-2) if(!t) HALT(3) PUT2(0, n / t) break;
case 0x1c: /* AND */ t=T;n=N; SET(2,-1) PUT(0, n & t) break;
case 0x3c: t=T2;n=N2; SET(4,-2) PUT2(0, n & t) break;
case 0x1d: /* ORA */ t=T;n=N; SET(2,-1) PUT(0, n | t) break;
case 0x3d: t=T2;n=N2; SET(4,-2) PUT2(0, n | t) break;
case 0x1e: /* EOR */ t=T;n=N; SET(2,-1) PUT(0, n ^ t) break;
case 0x3e: t=T2;n=N2; SET(4,-2) PUT2(0, n ^ t) break;
case 0x1f: /* SFT */ t=T;n=N; SET(2,-1) PUT(0, n >> (t & 0xf) << (t >> 4)) break;
case 0x3f: t=T;n=H2; SET(3,-1) PUT2(0, n >> (t & 0xf) << (t >> 4)) break;
}
}
}