4.3BSD - /usr/src/usr.bin/efl/field.c

   1: #include "defs"
   2: 
   3: 
   4: 
   5: ptr mkfield(q)
   6: register ptr q;
   7: {
   8: register ptr p;
   9: 
  10: if(!instruct)
  11:     goto err;
  12: else if(q->upperb == 0)
  13:     dclerr("must have upper bound in field spcification", "");
  14: else
  15:     {
  16:     p = ALLOC(fieldspec);
  17:     p->tag = TFIELD;
  18:     if(q->lowerb)
  19:         {
  20:         p->flbound = q->lowerb;
  21:         p->frange = mknode(TAROP,OPPLUS,mknode(TAROP,OPMINUS,
  22:                 q->upperb, cpexpr(q->lowerb)),
  23:                 mkconst(TYINT,"1") );
  24:         }
  25:     else    {
  26:         p->flbound = mkconst(TYINT,"1");
  27:         p->frange = q->upperb;
  28:         }
  29:     p->frange = simple(RVAL,p->frange);
  30:     if(p->frange->tag != TCONST)
  31:         {
  32:         dclerr("field range must be constant", "");
  33:         cfree(p);
  34:         goto err;
  35:         }
  36:     cfree(q);
  37:     return(p);
  38:     }
  39: 
  40: err:
  41:     cfree(q);
  42:     return( errnode() );
  43: }
  44: 
  45: 
  46: 
  47: 
  48: 
  49: ptr extrfield(p)
  50: register ptr p;
  51: {
  52: register ptr t;
  53: 
  54: t = p->vtypep;
  55: p->vtype = TYINT;
  56: p->vtypep = 0;
  57: 
  58: if(t->frshift)
  59:     p = mknode(TAROP,OPSLASH, p, cpexpr(t->frshift));
  60: if(t->fanymore)
  61:     p = mkcall(builtin(TYINT, "mod"), arg2(p, cpexpr(t->frange)) );
  62: p = mknode(TAROP,OPPLUS, p, cpexpr(t->flbound));
  63: return(p);
  64: }
  65: 
  66: 
  67: 
  68: 
  69: ptr setfield(e)
  70: ptr e;
  71: {
  72: ptr lp, rp;
  73: register ptr f, p;
  74: int subt;
  75: 
  76: lp = cpexpr(e->leftp);
  77: rp = e->rightp;
  78: subt = e->subtype;
  79: f = lp->vtypep;
  80: lp->vtype = TYINT;
  81: lp->vtypep = 0;
  82: 
  83: if(subt==OPPLUS || subt==OPMINUS)
  84:     {
  85:     if(f->frshift)
  86:         rp = mknode(TAROP,OPSTAR,rp,cpexpr(f->frshift));
  87:     }
  88: else    {
  89:     if(subt != OPASGN)
  90:         {
  91:         rp = mknode(TAROP,subt, extrfield(cpexpr(e->leftp)), rp);
  92:         subt = OPASGN;
  93:         }
  94:     rp = coerce(TYINT,rp);
  95:     if(f->flbound)
  96:         rp = simple(RVAL, mknode(TAROP,OPMINUS,rp,cpexpr(f->flbound)) );
  97: 
  98:     if(f->frshift==0)
  99:         {
 100:         if(f->fanymore)
 101:             {
 102:             p = mknode(TAROP,OPSLASH,cpexpr(lp),cpexpr(f->frange));
 103:             p->needpar = YES;
 104:             p = mknode(TAROP,OPSTAR,cpexpr(f->frange),p);
 105:             rp = mknode(TAROP,OPPLUS,p,rp);
 106:             }
 107:         }
 108:     else if(f->fanymore==0)
 109:         {
 110:         rp = mknode(TAROP,OPSTAR,cpexpr(f->frshift),rp);
 111:         p = mkcall(builtin(TYINT,"mod"),
 112:             arg2(cpexpr(lp),cpexpr(f->frshift)) );
 113:         rp = mknode(TAROP,OPPLUS, p,rp);
 114:         }
 115:     else    {
 116:         p = mknode(TAROP,OPSLASH,cpexpr(lp),cpexpr(f->frshift));
 117:         p = mkcall(builtin(TYINT,"mod"),
 118:             arg2(p, cpexpr(f->frange)) );
 119:         if( rp->tag!=TCONST || !equals(rp->leftp, "0") )
 120:             p = mknode(TAROP,OPMINUS, p, rp);
 121:         rp = mknode(TAROP,OPSTAR, cpexpr(f->frshift), p);
 122:         rp = mknode(TAROP,OPMINUS, cpexpr(lp), rp);
 123:         }
 124:     }
 125: frexpr( simple(LVAL, mknode(TASGNOP,subt,lp,rp) ));
 126: return(extrfield(e->leftp));
 127: }

Defined functions