ref: 75d6267a5f788162d92e7a5ae126cd8b0770aa8a
dir: /sys/src/cmd/aux/realemu/arg.c/
#include <u.h> #include <libc.h> #include "dat.h" #include "fns.h" #define ause(cpu) (cpu->abuf + (cpu->iabuf++ % nelem(cpu->abuf))) Iarg* adup(Iarg *x) { Iarg *a; a = ause(x->cpu); *a = *x; return a; } Iarg* areg(Cpu *cpu, uchar len, uchar reg) { Iarg *a; a = ause(cpu); a->cpu = cpu; a->tag = TREG; a->len = len; a->reg = reg; return a; } Iarg* amem(Cpu *cpu, uchar len, uchar sreg, ulong off) { Iarg *a; a = ause(cpu); a->cpu = cpu; a->tag = TMEM; a->len = len; a->sreg = sreg; a->seg = cpu->reg[sreg]; a->off = off; return a; } Iarg* afar(Iarg *mem, uchar len, uchar alen) { Iarg *a, *p; p = adup(mem); p->len = alen; a = amem(mem->cpu, len, R0S, ar(p)); p->off += alen; p->len = 2; a->seg = ar(p); return a; } Iarg* acon(Cpu *cpu, uchar len, ulong val) { Iarg *a; a = ause(cpu); a->cpu = cpu; a->tag = TCON; a->len = len; a->val = val; return a; } ulong ar(Iarg *a) { ulong w, o; Bus *io; switch(a->tag){ default: abort(); case TMEM: o = ((a->seg<<4) + (a->off & 0xFFFF)) & 0xFFFFF; io = a->cpu->mem + (o>>16); w = io->r(io->aux, o, a->len); break; case TREG: w = a->cpu->reg[a->reg]; break; case TREG|TH: w = a->cpu->reg[a->reg] >> 8; break; case TCON: w = a->val; break; } switch(a->len){ default: abort(); case 1: w &= 0xFF; break; case 2: w &= 0xFFFF; break; case 4: break; } return w; } long ars(Iarg *a) { ulong w = ar(a); switch(a->len){ default: abort(); case 1: return (char)w; case 2: return (short)w; case 4: return (long)w; } } void aw(Iarg *a, ulong w) { ulong *p, o; Cpu *cpu; Bus *io; cpu = a->cpu; switch(a->tag){ default: abort(); case TMEM: o = ((a->seg<<4) + (a->off & 0xFFFF)) & 0xFFFFF; io = cpu->mem + (o>>16); io->w(io->aux, o, w, a->len); break; case TREG: p = cpu->reg + a->reg; switch(a->len){ case 4: *p = w; break; case 2: *p = (*p & ~0xFFFF) | (w & 0xFFFF); break; case 1: *p = (*p & ~0xFF) | (w & 0xFF); break; } break; case TREG|TH: p = cpu->reg + a->reg; *p = (*p & ~0xFF00) | (w & 0xFF)<<8; break; } }