4.3BSD - /usr/src/new/icon/operators/refresh.c

   1: #include "../h/rt.h"
   2: #ifdef VAX
   3: /*
   4:  * ^x - return an entry block for co-expression x from the refresh block.
   5:  */
   6: 
   7: refresh(nargs, arg1, arg0)
   8: int nargs;
   9: struct descrip arg1, arg0;
  10:    {
  11:    register int *ap, *sp, *tp;
  12:    struct descrip *dp, *dsp;
  13:    register struct b_estack *ep;
  14:    register struct b_eblock *hp;
  15:    int na, nl, *r5, *newap;
  16:    extern struct b_estack *alcestk();
  17:    extern interp();
  18: 
  19:    SetBound;
  20:    DeRef(arg1)
  21:    if (QUAL(arg1) || TYPE(arg1) != T_ESTACK)
  22:       runerr(118, &arg1);
  23: 
  24:    /*
  25:     * Get a new co-expression stack and initialize activator, result
  26:     *  count, stack base, and fresh block location.
  27:     */
  28:    esneed();
  29:    ep = alcestk();
  30:    ep->activator = nulldesc;
  31:    ep->nresults = 0;
  32:    ep->freshblk = BLKLOC(arg1)->estack.freshblk;
  33:    ep->sbase = sp = (int *)ep;
  34:    /*
  35:     * Get number of arguments, number of locals, and a pointer to
  36:     *  arg0 in the refresh block's argument list.
  37:     */
  38:    hp = (struct b_eblock *) BLKLOC(ep->freshblk);
  39:    na = hp->numargs;
  40:    nl = hp->numlocals;
  41:    ap = (int *) hp->elems;
  42: 
  43:    /*
  44:     * Copy arguments into new stack and refresh block.
  45:     */
  46:    dsp = (struct descrip *) sp;
  47:    dp = (struct descrip *) ap;
  48:    *--dsp = *dp++;
  49:    while (na-- > 0) {
  50:       *--dsp = *dp++;
  51:       }
  52:    sp = (int *) dsp;
  53:    ap = (int *) dp;
  54: 
  55:    /*
  56:     * Set up original procedure frame in new stack.
  57:     */
  58:    *--sp = hp->numargs;         /* nargs */
  59:    *--sp = (hp->numargs*2) + 1;     /* nwords */
  60:    newap = sp;              /* save address of nwords */
  61:    *--sp = (int) interp;        /* return pc */
  62:    *--sp = 0;               /* saved r5 (frame pointer) */
  63:    *--sp = 0;               /* saved ap */
  64:    *--sp = 0;               /* psw/reg. mask */
  65:    *--sp = 0;               /* condition handler */
  66:    r5 = sp;             /* (save its address) */
  67:    *--sp = line;            /* saved line number */
  68:    *--sp = (int) file;          /* saved file name */
  69: 
  70:    /*
  71:     * Copy local variables into new stack.
  72:     */
  73:    dsp = (struct descrip *) sp;
  74:    dp = (struct descrip *) ap;
  75:    while (nl-- > 0) {
  76:       *--dsp = *dp++;
  77:       }
  78:    sp = (int *) dsp;
  79:    ap = (int *) dp;
  80: 
  81:    /*
  82:     * Set up dummy call to coact.
  83:     */
  84:    *--sp = nulldesc.type;       /* place for result */
  85:    *--sp = INTVAL(nulldesc);
  86:    *--sp = nulldesc.type;       /* place for activate coexpr */
  87:    *--sp = INTVAL(nulldesc);
  88:    *--sp = 1;               /* nargs */
  89:    *--sp = 3;               /* nwords */
  90:    tp = sp;             /* save pointer to start of arg
  91:                                             list in this frame */
  92:    *--sp = (int) hp->ep;        /* saved r9 (coexpr entry point) */
  93:    *--sp = (int) interp;        /* return pc (entry point) */
  94:    *--sp = (int) r5;            /* saved r5 */
  95:    *--sp = (int) newap;         /* saved ap */
  96:    *--sp = 0x02000000;          /* psw/reg mask with bit set to
  97:                                             restore r9, the ipc */
  98:    *--sp = 0;
  99:    ep->boundary = sp;           /* (initial boundary) */
 100:    *--sp = line;            /* saved line number */
 101:    *--sp = (int) file;          /* saved file name */
 102:    ep->sp = sp;             /* initial stack pointer */
 103:    ep->ap = tp;
 104: 
 105:    /*
 106:     * Return the new co-expression.
 107:     */
 108:    arg0.type = D_ESTACK;
 109:    BLKLOC(arg0) = (union block *) ep;
 110:    ClearBound;
 111:    }
 112: 
 113: Opblock(refresh,1,"^")
 114: #endif VAX
 115: 
 116: #ifdef PORT
 117: refresh()
 118: {
 119:    syserr("Attempt to refresh a co-expression");
 120: }
 121: #endif PORT
 122: #ifdef PDP11
 123: /*
 124:  * ^x - return an entry block for co-expression x from the refresh block.
 125:  * NOTE:  this code is highly dependent on stack frame layout.
 126:  */
 127: 
 128: refresh(nargs, arg1, arg0)
 129: int nargs;
 130: struct descrip arg1, arg0;
 131:    {
 132:    register int *ap, *sp;
 133:    register struct b_estack *ep;
 134:    register struct b_eblock *hp;
 135:    int na, nl, *r5;
 136:    extern struct b_estack *alcestk();
 137:    extern interp();
 138: 
 139:    DeRef(arg1)
 140:    if (QUAL(arg1) || TYPE(arg1) != T_ESTACK)
 141:       runerr(118, &arg1);
 142: 
 143:    esneed();                            /* check for room in stack space */
 144:    ep = alcestk();                      /* allocate expression stack */
 145:    ep->activator = nulldesc;
 146:    ep->nresults = 0;
 147:    ep->freshblk = BLKLOC(arg1)->estack.freshblk;
 148: 
 149:    ep->sbase = sp = (int *)ep;      /* initialize new stack pointer */
 150:    hp = BLKLOC(ep->freshblk);
 151:    na = hp->numargs;                /* get value of nargs */
 152:    nl = hp->numlocals;
 153:    ap = hp->elems;                  /* find arg0 of caller */
 154: 
 155:    /* copy arguments into new stack and refresh block */
 156:    *--(struct descrip *)sp = *(struct descrip *)ap;   /* copy arg0 */
 157:    while (na-- > 0)
 158:       *--(struct descrip *)sp = *++(struct descrip *)ap;
 159: 
 160:    /* set up original procedure frame in new stack */
 161:    *--sp = hp->numargs;         /* copy nargs */
 162:    *--sp = 0;               /* return pc */
 163:    *--sp = 0;               /* saved r5 */
 164:    r5 = sp;             /*   (save its address) */
 165:    *--sp = 0;               /* saved r4 */
 166:    *--sp = 0;               /* saved r3 */
 167:    *--sp = 0;               /* saved r2 */
 168:    *--sp = line;            /* saved line number */
 169:    *--sp = file;            /* saved file name */
 170: 
 171:    /* copy local variables into new stack */
 172:    while (nl-- > 0)
 173:       *--(struct descrip *)sp = *++(struct descrip *)ap;
 174: 
 175:    /* set up dummy call to activate */
 176:    *--(struct descrip *)sp = nulldesc;  /* place for result */
 177:    *--(struct descrip *)sp = nulldesc;  /* place for activate coexpr */
 178:    /* these values are the initial register state for the coexpression */
 179:    *--sp = 1;               /* nargs */
 180:    *--sp = interp;                  /* return pc (entry point) */
 181:    *--sp = r5;              /* saved r5 */
 182:    ep->boundary = sp;           /*   (initial boundary) */
 183:    *--sp = 0;               /* saved r4 */
 184:    *--sp = 0;               /* saved r3 */
 185:    *--sp = hp->ep;          /* saved r2 */
 186:    *--sp = line;            /* saved line number */
 187:    *--sp = file;            /* saved file name */
 188:    ep->sp = sp;             /* initial stack pointer */
 189:    arg0.type = D_ESTACK;
 190:    BLKLOC(arg0) = ep;
 191:    }
 192: Opblock(refresh,1,"^")
 193: #endif PDP11

Defined functions