#include cc.def/1

extern char line[];
extern int lptr;
extern char *cptr;
expression()
{
      int lval[2];
      if(heir1(lval))rvalue(lval);
} /* expression */


heir1(lval)
      int lval[];
{
      int k,lval2[2];

      k=heir1a(lval);
      if (match("=")) {
             if(k==0){
                    needlval();
                    return 0;
                    }
             if (lval[1])push();
             if(heir1(lval2))rvalue(lval2);
             store(lval);
             return 0;
             }
      else return k;
}  /* heir1 */



heir1a(lval)   /* Process exp ? exp : exp */
      int lval[];
{
      int k;

      k = heir1b(lval);
      blanks();
      if(match("?")) {
             error("?: expressions not implemented");
             kill();
             return 0;
             }
      else
             return k;
} /* heir1a */
heir1b(lval) /* process exp || exp */
      int lval[];
{
      int k, lval2[2];

      k = heir1c(lval);
      blanks();
      if(ch() != '|') return k;
      if(nch() != '|') return k;

      if(k) rvalue(lval);
      forever  {
             if(match("||")) {
                    push();
                    if(heir1c(lval2)) rvalue(lval2);
                    pop();
                    or();
                    }
             else
                    return 0;
             }
} /* heir1b */

heir1c(lval)        /* process exp && exp */
      int lval[];
{
      int k, lval2[2];

      k = heir2(lval);
      blanks();

      if(ch() != '&') return k;
      if(nch() != '&') return k;

      if(k) rvalue(lval);
      forever  {
             if(match("&&")) {
                    push();
                    if(heir2(lval2)) rvalue(lval2);
                    pop();
                    land();
                    }
             else
                    return 0;
             }
} /* heir1c */

heir2(lval)
      int lval[];
{
      int k,lval2[2];
      k=heir3(lval);
      blanks();
      if(ch()!='|')return k;
      if(nch() == '|') return k;
      if(k)rvalue(lval);
      forever {
             if (match("|")) {
                    push();
                    if(heir3(lval2)) rvalue(lval2);
                    pop();
                    or();
                    }
             else return 0;
             }
} /* heir2 */


heir3(lval)
      int lval[];
{
      int k,lval2[2];
      k=heir4(lval);
      blanks();
      if(ch()!='^')return k;
      if(k)rvalue(lval);
      forever {
             if (match("^")) {
                    push();
                    if(heir4(lval2))rvalue(lval2);
                    pop();
                    xor();
                    }
             else return 0;
             }
} /* heir3 */
heir4(lval)
        int lval[];
{       int k,lval2[2];
        k=heir5(lval);
        blanks();
        if(ch()!='&')return k;
        if(nch() == '&') return k;
        if(k)rvalue(lval);
        forever
                {if (match("&"))
                        {push();
                        if(heir5(lval2))rvalue(lval2);
                        pop();
                        and();
                        }
                else return 0;
                }
}
heir5(lval)
        int lval[];
{
        int k,lval2[2];
        k=heir6(lval);
        blanks();
        if((streq(line+lptr,"==")==0)&
                (streq(line+lptr,"!=")==0))return k;
        if(k)rvalue(lval);
        forever
                {if (match("=="))
                        {push();
                        if(heir6(lval2))rvalue(lval2);
                        pop();
                        eq();
                        }
                else if (match("!="))
                        {push();
                        if(heir6(lval2))rvalue(lval2);
                        pop();
                        ne();
                        }
                else return 0;
                }
}
heir6(lval)
        int lval[];
{
        int k,lval2[2];
        k=heir7(lval);
        blanks();
        if((streq(line+lptr,"<")==0)&
                (streq(line+lptr,">")==0)&
                (streq(line+lptr,"<=")==0)&
                (streq(line+lptr,">=")==0))return k;
                if(streq(line+lptr,">>"))return k;
                if(streq(line+lptr,"<<"))return k;
        if(k)rvalue(lval);
        forever
                {if (match("<="))
                        {push();
                        if(heir7(lval2))rvalue(lval2);
                        pop();
                        if(cptr=lval[0])
                                if(cptr[ident]==pointer)
                                {ule();
                                continue;
                                }
                        if(cptr=lval2[0])
                                if(cptr[ident]==pointer)
                                {ule();
                                continue;
                                }
                        le();
                        }
                else if (match(">="))
                        {push();
                        if(heir7(lval2))rvalue(lval2);
                        pop();
                        if(cptr=lval[0])
                                if(cptr[ident]==pointer)
                                {uge();
                                continue;
                                }
                        if(cptr=lval2[0])
                                if(cptr[ident]==pointer)
                                {uge();
                                continue;
                                }
                        ge();
                        }
                else if((streq(line+lptr,"<"))&
                        (streq(line+lptr,"<<")==0))
                        {inbyte();
                        push();
                        if(heir7(lval2))rvalue(lval2);
                        pop();
                        if(cptr=lval[0])
                                if(cptr[ident]==pointer)
                                {ult();
                                continue;
                                }
                        if(cptr=lval2[0])
                                if(cptr[ident]==pointer)
                                {ult();
                                continue;
                                }
                        lt();
                        }
                else if((streq(line+lptr,">"))&
                        (streq(line+lptr,">>")==0))
                        {inbyte();
                        push();
                        if(heir7(lval2))rvalue(lval2);
                        pop();
                        if(cptr=lval[0])
                                if(cptr[ident]==pointer)
                                {ugt();
                                continue;
                                }
                        if(cptr=lval2[0])
                                if(cptr[ident]==pointer)
                                {ugt();
                                continue;
                                }
                        gt();
                        }
                else return 0;
                }
}