478 lines
10 KiB
C
478 lines
10 KiB
C
/* $Id$ */
|
|
/*
|
|
* (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
|
|
* See the copyright notice in the ACK home directory, in the file "Copyright".
|
|
*/
|
|
#include <stdio.h>
|
|
#include "symtab.h"
|
|
#include "sizes.h"
|
|
#include "expr.h"
|
|
#include "Lpars.h"
|
|
|
|
static void rvalue(), assignable(), inputable(), outputable(), subscriptable();
|
|
static void assigned();
|
|
char *Malloc();
|
|
|
|
/* The new_* functions make use of the used() and assinged() functions to
|
|
* make known what is done to a variable.
|
|
*/
|
|
|
|
struct expr *new_node(op, left, right, byte)
|
|
int op;
|
|
register struct expr *left, *right;
|
|
int byte;
|
|
/* Makes a new node with given operator, left and right operand.
|
|
* Constant folding is done if possible.
|
|
*/
|
|
{
|
|
if (op!=FOR && constant(left) && (right==nil || constant(right))) {
|
|
register long lc, rc;
|
|
|
|
lc=left->u.cst;
|
|
if (right) rc=right->u.cst; else rc = 0;
|
|
|
|
switch (op) {
|
|
case '+': lc+=rc; break;
|
|
case '-': lc-=rc; break;
|
|
case '*': lc*=rc; break;
|
|
case '/': if (rc==0L)
|
|
report("division by zero");
|
|
else
|
|
lc/=rc;
|
|
break;
|
|
case BS: lc%=rc; break;
|
|
case '<': lc= lc<rc ? -1L : 0L; break;
|
|
case '>': lc= lc>rc ? -1L : 0L; break;
|
|
case LE: lc= lc<=rc ? -1L : 0L; break;
|
|
case GE: lc= lc>=rc ? -1L : 0L; break;
|
|
case NE: lc= lc!=rc ? -1L : 0L; break;
|
|
case '=': lc= lc==rc ? -1L : 0L; break;
|
|
case AFTER: lc= (lc-rc)>0 ? -1L : 0L; break;
|
|
case BA: lc&=rc; break;
|
|
case BO: lc|=rc; break;
|
|
case BX: lc^=rc; break;
|
|
case AND: lc= lc&&rc ? -1L : 0L; break;
|
|
case OR: lc= lc||rc ? -1L : 0L; break;
|
|
case LS: lc<<=rc; break;
|
|
case RS: lc>>=rc; break;
|
|
case '~': lc= -lc; break;
|
|
case NOT: lc= ~lc; break;
|
|
default:
|
|
report("illegal operator on constants");
|
|
}
|
|
destroy(right);
|
|
|
|
left->u.cst=lc;
|
|
return left;
|
|
} else {
|
|
register struct expr *pe;
|
|
int type=0, arr_siz=1;
|
|
|
|
switch (op) {
|
|
case '+': case '-': case '*': case '/':
|
|
case BS: case '<': case '>': case LE:
|
|
case GE: case NE: case '=': case AFTER:
|
|
case BA: case BO: case BX: case AND:
|
|
case OR: case LS: case RS:
|
|
rvalue(left);
|
|
rvalue(right);
|
|
type=T_VALUE;
|
|
break;
|
|
case '~':
|
|
case NOT:
|
|
rvalue(left);
|
|
type=T_VALUE;
|
|
break;
|
|
case AS:
|
|
assignable(left, right);
|
|
type=T_VOID;
|
|
break;
|
|
case '[':
|
|
subscriptable(left, right, byte, &type, &arr_siz);
|
|
break;
|
|
}
|
|
pe= (struct expr *) Malloc(sizeof *pe);
|
|
|
|
pe->kind=E_NODE;
|
|
pe->type=type;
|
|
pe->arr_siz=arr_siz;
|
|
pe->u.node.op=op;
|
|
pe->u.node.left=left;
|
|
pe->u.node.right=right;
|
|
|
|
return pe;
|
|
}
|
|
}
|
|
|
|
struct expr *new_var(var)
|
|
register struct symbol *var;
|
|
/* Given a variable an expression node is constructed. Note the changes in
|
|
* type! T_VAR becomes T_VALUE with flag T_LVALUE.
|
|
*/
|
|
{
|
|
register struct expr *pe;
|
|
|
|
pe= (struct expr *) Malloc(sizeof *pe);
|
|
|
|
pe->kind=E_VAR;
|
|
|
|
if ((var->s_type&T_TYPE)==T_VAR || var->s_type&T_NOTDECL) {
|
|
pe->type=(var->s_type&(~T_TYPE));
|
|
pe->type|=T_VALUE|T_LVALUE;
|
|
} else
|
|
pe->type=var->s_type;
|
|
|
|
pe->arr_siz=var->s_arr_siz;
|
|
|
|
pe->u.var=var;
|
|
|
|
return pe;
|
|
}
|
|
|
|
struct expr *new_const(cst)
|
|
long cst;
|
|
/* Make a constant, which is a VALUE, of course. */
|
|
{
|
|
register struct expr *pe;
|
|
|
|
pe= (struct expr *) Malloc(sizeof *pe);
|
|
|
|
pe->kind=E_CONST;
|
|
pe->type=T_VALUE;
|
|
pe->u.cst=cst;
|
|
|
|
return pe;
|
|
}
|
|
|
|
struct expr *new_table(kind, tab)
|
|
register kind;
|
|
register struct table *tab;
|
|
/* One table is being made, it is no doubt a VALUEd ARRay, but maybe even a
|
|
* BYTE array. A label is reserved for it and the individual elements are
|
|
* rommified.
|
|
*/
|
|
{
|
|
register struct expr *pe;
|
|
|
|
pe= (struct expr *) Malloc(sizeof *pe);
|
|
|
|
pe->kind=kind;
|
|
pe->type=T_VALUE|T_ARR;
|
|
if (kind==E_BTAB) pe->type|=T_BYTE;
|
|
dot_label(new_dot_label(&pe->u.tab));
|
|
|
|
pe->arr_siz=0;
|
|
while (tab!=nil) {
|
|
register struct table *junk=tab;
|
|
|
|
rom(kind==E_BTAB ? 1 : vz, tab->val);
|
|
|
|
tab=tab->next;
|
|
pe->arr_siz++;
|
|
free((char *)junk);
|
|
}
|
|
|
|
return pe;
|
|
}
|
|
|
|
struct expr *copy_const(e) struct expr *e;
|
|
/* If you double it up, you've got one you can throw away. (Or do something
|
|
* useful with).
|
|
*/
|
|
{
|
|
register struct expr *c;
|
|
|
|
c= (struct expr *) Malloc(sizeof *c);
|
|
|
|
*c= *e;
|
|
return c;
|
|
}
|
|
|
|
struct expr *new_now()
|
|
/* Now is the time to make a VALUE cell for the clock. */
|
|
{
|
|
register struct expr *pe;
|
|
|
|
pe= (struct expr *) Malloc(sizeof *pe);
|
|
|
|
pe->kind=E_NOW;
|
|
pe->type=T_VALUE;
|
|
|
|
return pe;
|
|
}
|
|
|
|
struct expr *new_io(out, chan, args)
|
|
int out;
|
|
register struct expr *chan;
|
|
struct expr_list *args;
|
|
/* Either c ? v0; v1; v2; ... (out=0) or c ! e0; e1; e2; ... (out=1). */
|
|
{
|
|
register struct expr *pe;
|
|
|
|
if ( ( (chan->type&T_TYPE) != T_CHAN || (chan->type&T_ARR) )
|
|
&& ! (chan->type&T_NOTDECL)
|
|
)
|
|
report("channel variable expected");
|
|
used(chan);
|
|
|
|
pe= (struct expr *) Malloc(sizeof *pe);
|
|
|
|
pe->kind=E_IO;
|
|
pe->type=T_VOID;
|
|
pe->u.io.out=out;
|
|
pe->u.io.chan=chan;
|
|
pe->u.io.args=args;
|
|
|
|
return pe;
|
|
}
|
|
|
|
struct expr *new_call(proc, args)
|
|
struct expr *proc;
|
|
struct expr_list *args;
|
|
/* Dial proc(arg1, arg2, ...) and you'll hear the tone of this function.
|
|
* Dialing yourself is not allowed, but it will work if you ignore the
|
|
* compiler generated noise.
|
|
*/
|
|
{
|
|
register struct expr *pe;
|
|
|
|
pe= (struct expr *) Malloc(sizeof *pe);
|
|
|
|
used(proc);
|
|
|
|
check_recursion(proc);
|
|
|
|
pe->kind=E_CALL;
|
|
pe->type=T_VOID;
|
|
pe->u.call.c_proc=proc;
|
|
pe->u.call.c_args=args;
|
|
|
|
return pe;
|
|
}
|
|
|
|
void table_add(aapt, val) register struct table ***aapt; long val;
|
|
/* Adds a value to a table using a hook to a hook. */
|
|
{
|
|
register struct table *pt;
|
|
|
|
pt= (struct table *) Malloc(sizeof *pt);
|
|
|
|
pt->val=val;
|
|
pt->next= **aapt;
|
|
|
|
**aapt=pt;
|
|
*aapt= &pt->next;
|
|
}
|
|
|
|
void expr_list_add(aaelp, arg)
|
|
register struct expr_list ***aaelp;
|
|
struct expr *arg;
|
|
/* Another add, this time for actual arguments and the like. */
|
|
{
|
|
register struct expr_list *elp;
|
|
|
|
elp= (struct expr_list *) Malloc(sizeof *elp);
|
|
|
|
elp->arg=arg;
|
|
elp->next= **aaelp;
|
|
**aaelp=elp;
|
|
*aaelp= &elp->next;
|
|
}
|
|
|
|
void check_io(out, arg) int out; struct expr *arg;
|
|
{
|
|
if (out)
|
|
outputable(arg);
|
|
else
|
|
inputable(arg);
|
|
}
|
|
|
|
void check_wait(e) struct expr *e;
|
|
{
|
|
if ((e->type&T_TYPE)!=T_VALUE)
|
|
report("WAIT process needs valued operand");
|
|
}
|
|
|
|
static void assigned(e) register struct expr *e;
|
|
/* Tries to tell e that it is assigned to. */
|
|
{
|
|
if (e->kind==E_VAR || (e->kind==E_NODE && e->u.node.op=='['
|
|
&& (e=e->u.node.left)->kind==E_VAR)
|
|
) {
|
|
register struct symbol *var;
|
|
|
|
if ((var=e->u.var)->s_type&T_REP) {
|
|
warning("replicator index %s may not be assigned",
|
|
var->s_name);
|
|
var->s_type&= ~T_REP;
|
|
}
|
|
var->s_type|=T_ASSIGNED;
|
|
}
|
|
}
|
|
|
|
void used(e) register struct expr *e;
|
|
{
|
|
if (e->kind==E_VAR || (e->kind==E_NODE && e->u.node.op=='['
|
|
&& (e=e->u.node.left)->kind==E_VAR)
|
|
) {
|
|
register struct symbol *var;
|
|
|
|
if ( ! ( (var=e->u.var)->s_type&(T_ASSIGNED|T_BUILTIN))
|
|
&& (var->s_type&T_TYPE)==T_VAR
|
|
&& var->s_info.vc.st.level==curr_level)
|
|
warning("%s used before assigned", var->s_name);
|
|
var->s_type|=(T_USED|T_ASSIGNED);
|
|
}
|
|
}
|
|
|
|
static void rvalue(e) register struct expr *e;
|
|
{
|
|
if ((e->type&T_TYPE)!=T_VALUE || e->type&T_ARR)
|
|
report("illegal operand of arithmetic operator");
|
|
used(e);
|
|
}
|
|
|
|
static void assignable(l, r) register struct expr *l, *r;
|
|
/* See if l can be assigned r. */
|
|
{
|
|
if ( ! ( (l->type&T_LVALUE && (r->type&T_TYPE)==T_VALUE
|
|
&& (l->type&T_ARR)==(r->type&T_ARR))
|
|
|| (l->type|r->type)&T_NOTDECL
|
|
))
|
|
report("operands of assignment are not conformable");
|
|
else
|
|
if (l->type&T_ARR && ! ( (l->type|r->type)&T_NOTDECL ) ) {
|
|
register lsiz=l->arr_siz, rsiz=r->arr_siz;
|
|
|
|
if (lsiz!=0 && rsiz!=0 && lsiz!=rsiz)
|
|
report("arrays have incompatible sizes");
|
|
}
|
|
used(r);
|
|
assigned(l);
|
|
|
|
}
|
|
|
|
static void inputable(e) struct expr *e;
|
|
{
|
|
if ( ! (e->type&T_LVALUE) )
|
|
report("operand of input process can't be assigned");
|
|
|
|
assigned(e);
|
|
}
|
|
|
|
static void outputable(e) struct expr *e;
|
|
{
|
|
if ( ! ( (e->type&T_TYPE)==T_VALUE ) )
|
|
report("operand of output process has no value");
|
|
used(e);
|
|
}
|
|
|
|
static void subscriptable(l, r, byte, atype, arr_siz)
|
|
register struct expr *l, *r;
|
|
register byte;
|
|
int *atype, *arr_siz;
|
|
/* Tries to subscript l by r, returning type and array size for slices. */
|
|
{
|
|
register type= (l->type&T_TYPE)|byte;
|
|
|
|
if ( !(l->type&(T_ARR|T_NOTDECL) ) )
|
|
report("indexing on a non-array");
|
|
else
|
|
if ( ! ( (r->type&T_TYPE)==T_VALUE
|
|
|| (r->kind==E_NODE && r->u.node.op==FOR)
|
|
) )
|
|
report("index is not computable");
|
|
|
|
type|=(l->type&T_LVALUE);
|
|
|
|
if (r->kind==E_NODE && r->u.node.op==FOR) {
|
|
type|=T_ARR;
|
|
if (r->u.node.right->kind!=E_CONST)
|
|
report("slice must be of constant size");
|
|
else
|
|
*arr_siz=r->u.node.right->u.cst;
|
|
used(r->u.node.left);
|
|
} else
|
|
used(r);
|
|
*atype=type;
|
|
}
|
|
|
|
void check_param(aform, act, err)
|
|
struct par_list **aform;
|
|
register struct expr *act;
|
|
int *err;
|
|
/* Test if formal parameter *aform corresponds with actual act. Err returns
|
|
* error status. The aform hook is set to the next formal after the check.
|
|
*/
|
|
{
|
|
register struct par_list *form= *aform;
|
|
register struct expr *left;
|
|
register struct symbol *var;
|
|
static char NONCORR[]="actual and formal parameter don't correspond";
|
|
|
|
if (form==nil) {
|
|
if (! *err) {
|
|
report("too many actual parameters");
|
|
*err=1;
|
|
}
|
|
return;
|
|
}
|
|
|
|
if ((form->pr_type&T_ARR)!=(act->type&T_ARR) && !(act->type&T_NOTDECL) ) {
|
|
report(NONCORR);
|
|
} else {
|
|
switch (form->pr_type&T_TYPE) {
|
|
case T_VAR:
|
|
if ( ! (
|
|
(act->type&T_TYPE)==T_VALUE
|
|
&& act->type&T_LVALUE
|
|
&& !(act->type&T_BYTE)
|
|
))
|
|
report(NONCORR);
|
|
assigned(act);
|
|
used(act);
|
|
break;
|
|
case T_CHAN:
|
|
if((act->type&T_TYPE)!=T_CHAN && !(act->type&T_NOTDECL))
|
|
report(NONCORR);
|
|
used(act);
|
|
break;
|
|
case T_VALUE:
|
|
if ((act->type&T_TYPE)!=T_VALUE)
|
|
report(NONCORR);
|
|
used(act);
|
|
break;
|
|
}
|
|
}
|
|
*aform= form->pr_next;
|
|
}
|
|
|
|
void destroy(e) register struct expr *e;
|
|
/* Opposite of making. */
|
|
{
|
|
if (e!=nil) {
|
|
switch (e->kind) {
|
|
case E_NODE:
|
|
destroy(e->u.node.left);
|
|
destroy(e->u.node.right);
|
|
break;
|
|
case E_IO:
|
|
case E_CALL:
|
|
destroy(e->kind==E_IO ? e->u.io.chan : e->u.call.c_proc);
|
|
{
|
|
register struct expr_list *elp, *junk;
|
|
|
|
elp= e->kind==E_IO ? e->u.io.args : e->u.call.c_args;
|
|
|
|
while (elp!=nil) {
|
|
destroy(elp->arg);
|
|
junk=elp;
|
|
elp=elp->next;
|
|
free((char *)junk);
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
free((char *)e);
|
|
}
|
|
}
|