/* clocal() is called to do local transformations on
* an expression tree preparitory to its being
* written out in intermediate code.
*
* the major essential job is rewriting the
* automatic variables and arguments in terms of
* REG and OREG nodes
* conversion ops which are not necessary are also clobbered here
* in addition, any special features (such as rewriting
* exclusive or) are easily handled here as well
*/
P1ND *
clocal(P1ND *p)
{
struct attr *ap;
register struct symtab *q;
register P1ND *r, *l, *n, *s;
register int o;
register int m;
#ifdef PCC_DEBUG
if (xdebug) {
printf("clocal: %p\n", p);
p1fwalk(p, eprint, 0);
}
#endif
switch( o = p->n_op ){
case NAME:
if ((q = p->n_sp) == NULL)
return p; /* Nothing to care about */
switch (q->sclass) {
case PARAM:
case AUTO:
/* fake up a structure reference */
r = block(REG, NIL, NIL, PTR+STRTY, 0, 0);
slval(r, 0);
r->n_rval = FPREG;
p = stref(block(STREF, r, p, 0, 0, 0));
break;
case USTATIC:
if (kflag == 0)
break;
/* FALLTHROUGH */
case STATIC:
#ifdef TLS
if (q->sflags & STLS) {
p = tlsref(p);
break;
}
#endif
if (kflag == 0) {
if (q->slevel == 0)
break;
} else if (kflag && !statinit && blevel > 0 &&
#ifdef GCC_COMPAT
attr_find(q->sap, GCC_ATYP_WEAKREF)) {
#else
0) {
#endif
/* extern call */
p = picext(p);
} else if (blevel > 0 && !statinit)
p = picstatic(p);
break;
case REGISTER:
p->n_op = REG;
slval(p, 0);
p->n_rval = q->soffset;
break;
case EXTERN:
case EXTDEF:
#ifdef TLS
if (q->sflags & STLS) {
p = tlsref(p);
break;
}
#endif
#ifdef PECOFFABI
if (q->sflags & SDLLINDIRECT)
p = import(p);
#endif
#ifdef GCC_COMPAT
if ((ap = attr_find(q->sap,
GCC_ATYP_VISIBILITY)) != NULL &&
strcmp(ap->sarg(0), "hidden") == 0)
printf(PRTPREF "\t.hidden %s\n", getsoname(q));
#endif
if (kflag == 0)
break;
if (blevel > 0 && !statinit)
p = picext(p);
break;
}
break;
case ADDROF:
if (kflag == 0 || blevel == 0 || statinit)
break;
/* char arrays may end up here */
l = p->n_left;
if (l->n_op != NAME ||
(l->n_type != ARY+CHAR && l->n_type != ARY+WCHAR_TYPE))
break;
l = p;
p = picstatic(p->n_left);
p1nfree(l);
if (p->n_op != UMUL)
cerror("ADDROF error");
l = p;
p = p->n_left;
p1nfree(l);
break;
case UCALL:
if (kflag == 0)
break;
l = block(REG, NIL, NIL, INT, 0, 0);
l->n_rval = EBX;
p->n_right = buildtree(ASSIGN, l, tempnode(gotnr, INT, 0, 0));
p->n_op -= (UCALL-CALL);
break;
case USTCALL:
#if defined(os_openbsd)
ap = strattr(p->n_left->n_ap);
if (ap->amsize == SZCHAR || ap->amsize == SZSHORT ||
ap->amsize == SZINT || ap->amsize == SZLONGLONG)
#else
if (attr_find(p->n_left->n_ap, ATTR_COMPLEX) &&
(ap = strattr(p->n_left->n_ap)) &&
ap->amsize == SZLONGLONG)
#endif
{
/* float complex */
/* fake one arg to make pass2 happy */
p->n_right = block(FUNARG, bcon(0), NIL, INT, 0, 0);
p->n_op -= (UCALL-CALL);
break;
}
/* Add hidden arg0 */
r = block(REG, NIL, NIL, INCREF(VOID), 0, 0);
regno(r) = EBP;
#ifdef GCC_COMPAT
if ((ap = attr_find(p->n_ap, GCC_ATYP_REGPARM)) != NULL &&
ap->iarg(0) > 0) {
l = block(REG, NIL, NIL, INCREF(VOID), 0, 0);
regno(l) = EAX;
p->n_right = buildtree(ASSIGN, l, r);
} else
#endif
p->n_right = block(FUNARG, r, NIL, INCREF(VOID), 0, 0);
p->n_op -= (UCALL-CALL);
if (kflag == 0)
break;
l = block(REG, NIL, NIL, INT, 0, 0);
regno(l) = EBX;
r = buildtree(ASSIGN, l, tempnode(gotnr, INT, 0, 0));
p->n_right = block(CM, r, p->n_right, INT, 0, 0);
break;
/* FALLTHROUGH */
#if defined(MACHOABI)
case CALL:
case STCALL:
if (p->n_type == VOID)
break;
r = tempnode(0, p->n_type, p->n_df, p->n_ap);
l = tcopy(r);
p = buildtree(COMOP, buildtree(ASSIGN, r, p), l);
#endif
break;
#ifdef notyet
/* XXX breaks sometimes */
case CBRANCH:
l = p->n_left;
/*
* Remove unnecessary conversion ops.
*/
if (!clogop(l->n_op) || l->n_left->n_op != SCONV)
break;
if (coptype(l->n_op) != BITYPE)
break;
if (l->n_right->n_op != ICON)
break;
r = l->n_left->n_left;
if (r->n_type >= FLOAT)
break;
if (toolarge(r->n_type, l->n_right->n_lval))
break;
l->n_right->n_type = r->n_type;
if (l->n_op >= ULE && l->n_op <= UGT)
l->n_op -= (UGT-ULE);
p->n_left = buildtree(l->n_op, r, l->n_right);
p1nfree(l->n_left);
p1nfree(l);
break;
#endif
case PCONV:
l = p->n_left;
/* Make int type before pointer */
if (l->n_type < INT || l->n_type == LONGLONG ||
l->n_type == ULONGLONG || l->n_type == BOOL) {
/* float etc? */
p->n_left = block(SCONV, l, NIL, UNSIGNED, 0, 0);
}
break;
case SCONV:
if (p->n_left->n_op == COMOP)
break; /* may propagate wrong type later */
l = p->n_left;
if (p->n_type == l->n_type) {
p1nfree(p);
return l;
}
if ((p->n_type & TMASK) == 0 && (l->n_type & TMASK) == 0 &&
tsize(p->n_type, p->n_df, p->n_ap) ==
tsize(l->n_type, l->n_df, l->n_ap)) {
if (p->n_type != FLOAT && p->n_type != DOUBLE &&
l->n_type != FLOAT && l->n_type != DOUBLE &&
l->n_type != LDOUBLE && p->n_type != LDOUBLE) {
if (l->n_op == NAME || l->n_op == UMUL ||
l->n_op == TEMP) {
l->n_type = p->n_type;
p1nfree(p);
return l;
}
}
}
if (DEUNSIGN(p->n_type) == INT && DEUNSIGN(l->n_type) == INT &&
coptype(l->n_op) == BITYPE && l->n_op != COMOP &&
l->n_op != QUEST && l->n_op != ASSIGN) {
l->n_type = p->n_type;
p1nfree(p);
return l;
}
o = l->n_op;
m = p->n_type;
if (o == ICON) {
/*
* Can only end up here if o is an address,
* and in that case the only compile-time conversion
* possible is to int.
*/
if ((TMASK & l->n_type) == 0 && l->n_sp == NULL)
cerror("SCONV ICON");
if (l->n_sp == 0) {
p->n_type = UNSIGNED;
concast(l, m);
} else if (m != INT && m != UNSIGNED)
break;
l->n_type = m;
l->n_ap = 0;
p1nfree(p);
return l;
} else if (l->n_op == FCON)
cerror("SCONV FCON");
if ((p->n_type == CHAR || p->n_type == UCHAR ||
p->n_type == SHORT || p->n_type == USHORT) &&
(l->n_type == FLOAT || l->n_type == DOUBLE ||
l->n_type == LDOUBLE)) {
p = block(SCONV, p, NIL, p->n_type, p->n_df, p->n_ap);
p->n_left->n_type = INT;
return p;
}
break;
case MOD:
case DIV:
if (o == DIV && p->n_type != CHAR && p->n_type != SHORT)
break;
if (o == MOD && p->n_type != CHAR && p->n_type != SHORT)
break;
/* make it an int division by inserting conversions */
p->n_left = makety(p->n_left, INT, 0, 0, 0);
p->n_right = makety(p->n_right, INT, 0, 0, 0);
o = p->n_type;
p->n_type = INT;
p = makety(p, o, 0, 0, 0);
break;
case FORCE:
/* put return value in return reg */
p->n_op = ASSIGN;
p->n_right = p->n_left;
p->n_left = block(REG, NIL, NIL, p->n_type, 0, 0);
p->n_left->n_rval = p->n_left->n_type == BOOL ?
RETREG(CHAR) : RETREG(p->n_type);
break;
case LS:
case RS:
/* shift count must be in a char */
if (p->n_right->n_type == CHAR || p->n_right->n_type == UCHAR)
break;
p->n_right = block(SCONV, p->n_right, NIL, CHAR, 0, 0);
break;
/* If not using pcc struct return */
case STASG:
r = p->n_right;
if (r->n_op != STCALL && r->n_op != USTCALL)
break;
m = tsize(BTYPE(r->n_type), r->n_df, r->n_ap);
if (m == SZCHAR)
m = CHAR;
else if (m == SZSHORT)
m = SHORT;
else if (m == SZINT)
m = INT;
else if (m == SZLONGLONG)
m = LONGLONG;
else
break;
#if !defined(os_openbsd)
if (attr_find(r->n_ap, ATTR_COMPLEX) == 0)
break; /* float _Complex always in regs */
#endif
l = buildtree(ADDROF, p->n_left, NIL);
p1nfree(p);
r->n_op -= (STCALL-CALL);
r->n_type = m;
/* r = long, l = &struct */
n = tempnode(0, m, r->n_df, r->n_ap);
r = buildtree(ASSIGN, p1tcopy(n), r);
s = tempnode(0, l->n_type, l->n_df, l->n_ap);
l = buildtree(ASSIGN, p1tcopy(s), l);
p = buildtree(COMOP, r, l);
l = buildtree(CAST,
block(NAME, NIL, NIL, m|PTR, 0, 0), p1tcopy(s));
r = l->n_right;
p1nfree(l->n_left);
p1nfree(l);
r = buildtree(ASSIGN, buildtree(UMUL, r, NIL), n);
p = buildtree(COMOP, p, r);
p = buildtree(COMOP, p, s);
break;
}
/*
* local optimizations, most of which are probably
* machine independent
*/
NODE *
optim(NODE *p)
{
int o, ty;
NODE *sp, *q;
OFFSZ sz;
int i;
if (odebug) return(p);
ty = coptype(p->n_op);
if( ty == LTYPE ) return(p);
if( ty == BITYPE ) p->n_right = optim(p->n_right);
p->n_left = optim(p->n_left);
/* collect constants */
again: o = p->n_op;
switch(o){
case SCONV:
if (concast(p->n_left, p->n_type)) {
q = p->n_left;
nfree(p);
p = q;
break;
}
/* FALLTHROUGH */
case PCONV:
if (p->n_type != VOID)
p = clocal(p);
break;
case FORTCALL:
p->n_right = fortarg( p->n_right );
break;
case ADDROF:
if (LO(p) == TEMP)
break;
if( LO(p) != NAME ) cerror( "& error" );
if( !andable(p->n_left) && !statinit)
break;
LO(p) = ICON;
setuleft:
/* paint over the type of the left hand side with the type of the top */
p->n_left->n_type = p->n_type;
p->n_left->n_df = p->n_df;
p->n_left->n_ap = p->n_ap;
q = p->n_left;
nfree(p);
p = q;
break;
case NOT:
case UMINUS:
case COMPL:
if (LCON(p) && conval(p->n_left, o, p->n_left))
p = nfree(p);
break;
case UMUL:
/* Do not discard ADDROF TEMP's */
if (LO(p) == ADDROF && LO(p->n_left) != TEMP) {
q = p->n_left->n_left;
nfree(p->n_left);
nfree(p);
p = q;
break;
}
if( LO(p) != ICON ) break;
LO(p) = NAME;
goto setuleft;
case RS:
if (LCON(p) && RCON(p) && conval(p->n_left, o, p->n_right))
goto zapright;
sz = tsize(p->n_type, p->n_df, p->n_ap);
if (LO(p) == RS && RCON(p->n_left) && RCON(p) &&
(RV(p) + RV(p->n_left)) < sz) {
/* two right-shift by constants */
RV(p) += RV(p->n_left);
p->n_left = zapleft(p->n_left);
}
#if 0
else if (LO(p) == LS && RCON(p->n_left) && RCON(p)) {
RV(p) -= RV(p->n_left);
if (RV(p) < 0)
o = p->n_op = LS, RV(p) = -RV(p);
p->n_left = zapleft(p->n_left);
}
#endif
if (RO(p) == ICON) {
if (RV(p) < 0) {
RV(p) = -RV(p);
p->n_op = LS;
goto again;
}
#ifdef notyet /* must check for side effects, --a >> 32; */
if (RV(p) >= tsize(p->n_type, p->n_df, p->n_sue) &&
ISUNSIGNED(p->n_type)) { /* ignore signed shifts */
/* too many shifts */
tfree(p->n_left);
nfree(p->n_right);
p->n_op = ICON; p->n_lval = 0; p->n_sp = NULL;
} else
#endif
/* avoid larger shifts than type size */
if (RV(p) >= sz) {
RV(p) = RV(p) % sz;
werror("shift larger than type");
}
if (RV(p) == 0)
p = zapleft(p);
}
break;
case LS:
if (LCON(p) && RCON(p) && conval(p->n_left, o, p->n_right))
goto zapright;
sz = tsize(p->n_type, p->n_df, p->n_ap);
if (LO(p) == LS && RCON(p->n_left) && RCON(p)) {
/* two left-shift by constants */
RV(p) += RV(p->n_left);
p->n_left = zapleft(p->n_left);
}
#if 0
else if (LO(p) == RS && RCON(p->n_left) && RCON(p)) {
RV(p) -= RV(p->n_left);
p->n_left = zapleft(p->n_left);
}
#endif
if (RO(p) == ICON) {
if (RV(p) < 0) {
RV(p) = -RV(p);
p->n_op = RS;
goto again;
}
#ifdef notyet /* must check for side effects */
if (RV(p) >= tsize(p->n_type, p->n_df, p->n_sue)) {
/* too many shifts */
tfree(p->n_left);
nfree(p->n_right);
p->n_op = ICON; p->n_lval = 0; p->n_sp = NULL;
} else
#endif
/* avoid larger shifts than type size */
if (RV(p) >= sz) {
RV(p) = RV(p) % sz;
werror("shift larger than type");
}
if (RV(p) == 0)
p = zapleft(p);
}
break;
case MINUS:
if (LCON(p) && RCON(p) && p->n_left->n_sp == p->n_right->n_sp) {
/* link-time constants, but both are the same */
/* solve it now by forgetting the symbols */
p->n_left->n_sp = p->n_right->n_sp = NULL;
}
if( !nncon(p->n_right) ) break;
RV(p) = -RV(p);
o = p->n_op = PLUS;
case MUL:
/*
* Check for u=(x-y)+z; where all vars are pointers to
* the same struct. This has two advantages:
* 1: avoid a mul+div
* 2: even if not allowed, people may get surprised if this
* calculation do not give correct result if using
* unaligned structs.
*/
if (p->n_type == INTPTR && RCON(p) &&
LO(p) == DIV && RCON(p->n_left) &&
RV(p) == RV(p->n_left) &&
LO(p->n_left) == MINUS) {
q = p->n_left->n_left;
if (q->n_left->n_type == PTR+STRTY &&
q->n_right->n_type == PTR+STRTY &&
strmemb(q->n_left->n_ap) ==
strmemb(q->n_right->n_ap)) {
p = zapleft(p);
p = zapleft(p);
}
}
/* FALLTHROUGH */
case PLUS:
case AND:
case OR:
case ER:
/* commutative ops; for now, just collect constants */
/* someday, do it right */
if( nncon(p->n_left) || ( LCON(p) && !RCON(p) ) )
SWAP( p->n_left, p->n_right );
/* make ops tower to the left, not the right */
if( RO(p) == o ){
NODE *t1, *t2, *t3;
t1 = p->n_left;
sp = p->n_right;
t2 = sp->n_left;
t3 = sp->n_right;
/* now, put together again */
p->n_left = sp;
sp->n_left = t1;
sp->n_right = t2;
sp->n_type = p->n_type;
p->n_right = t3;
}
if(o == PLUS && LO(p) == MINUS && RCON(p) && RCON(p->n_left) &&
conval(p->n_right, MINUS, p->n_left->n_right)){
zapleft:
q = p->n_left->n_left;
nfree(p->n_left->n_right);
nfree(p->n_left);
p->n_left = q;
}
if( RCON(p) && LO(p)==o && RCON(p->n_left) &&
conval( p->n_right, o, p->n_left->n_right ) ){
goto zapleft;
}
else if( LCON(p) && RCON(p) && conval( p->n_left, o, p->n_right ) ){
zapright:
nfree(p->n_right);
q = makety(p->n_left, p->n_type, p->n_qual,
p->n_df, p->n_ap);
nfree(p);
p = clocal(q);
break;
}
/* change muls to shifts */
if( o == MUL && nncon(p->n_right) && (i=ispow2(RV(p)))>=0){
if( i == 0 ) { /* multiplication by 1 */
goto zapright;
}
o = p->n_op = LS;
p->n_right->n_type = INT;
p->n_right->n_df = NULL;
RV(p) = i;
}
/* change +'s of negative consts back to - */
if( o==PLUS && nncon(p->n_right) && RV(p)<0 ){
RV(p) = -RV(p);
o = p->n_op = MINUS;
}
/* remove ops with RHS 0 */
if ((o == PLUS || o == MINUS || o == OR || o == ER) &&
nncon(p->n_right) && RV(p) == 0) {
goto zapright;
}
break;
case DIV:
if( nncon( p->n_right ) && p->n_right->n_lval == 1 )
goto zapright;
if (LCON(p) && RCON(p) && conval(p->n_left, DIV, p->n_right))
goto zapright;
if (RCON(p) && ISUNSIGNED(p->n_type) && (i=ispow2(RV(p))) > 0) {
p->n_op = RS;
RV(p) = i;
q = p->n_right;
if(tsize(q->n_type, q->n_df, q->n_ap) > SZINT)
p->n_right = makety(q, INT, 0, 0, 0);
break;
}
break;
case MOD:
if (RCON(p) && ISUNSIGNED(p->n_type) && ispow2(RV(p)) > 0) {
p->n_op = AND;
RV(p) = RV(p) -1;
break;
}
break;
case EQ:
case NE:
case LT:
case LE:
case GT:
case GE:
case ULT:
case ULE:
case UGT:
case UGE:
if( !LCON(p) ) break;
/* exchange operands */
sp = p->n_left;
p->n_left = p->n_right;
p->n_right = sp;
p->n_op = revrel[p->n_op - EQ ];
break;
#ifdef notyet
case ASSIGN:
/* Simple test to avoid two branches */
if (RO(p) != NE)
break;
q = p->n_right;
if (RCON(q) && RV(q) == 0 && LO(q) == AND &&
RCON(q->n_left) && (i = ispow2(RV(q->n_left))) &&
q->n_left->n_type == INT) {
q->n_op = RS;
RV(q) = i;
}
break;
#endif
}
return(p);
}
/* clocal() is called to do local transformations on
* an expression tree preparitory to its being
* written out in intermediate code.
*
* the major essential job is rewriting the
* automatic variables and arguments in terms of
* REG and OREG nodes
* conversion ops which are not necessary are also clobbered here
* in addition, any special features (such as rewriting
* exclusive or) are easily handled here as well
*/
NODE *
clocal(NODE *p)
{
register struct symtab *q;
register NODE *r, *l;
register int o;
TWORD t;
#ifdef PCC_DEBUG
if (xdebug) {
printf("clocal: %p\n", p);
fwalk(p, eprint, 0);
}
#endif
switch( o = p->n_op ){
case NAME:
if ((q = p->n_sp) == NULL)
return p; /* Nothing to care about */
switch (q->sclass) {
case PARAM:
case AUTO:
/* fake up a structure reference */
r = block(REG, NIL, NIL, PTR+STRTY, 0, 0);
slval(r, 0);
r->n_rval = FPREG;
p = stref(block(STREF, r, p, 0, 0, 0));
break;
case REGISTER:
p->n_op = REG;
slval(p, 0);
p->n_rval = q->soffset;
break;
case USTATIC:
case STATIC:
if (kflag == 0)
break;
if (blevel > 0 && !statinit)
p = picstatic(p);
break;
case EXTERN:
case EXTDEF:
if (kflag == 0)
break;
if (blevel > 0 && !statinit)
p = picext(p);
break;
}
break;
case ADDROF:
if (kflag == 0 || blevel == 0 || statinit)
break;
/* char arrays may end up here */
l = p->n_left;
if (l->n_op != NAME ||
(l->n_type != ARY+CHAR && l->n_type != ARY+WCHAR_TYPE))
break;
l = p;
p = picstatic(p->n_left);
nfree(l);
if (p->n_op != UMUL)
cerror("ADDROF error");
l = p;
p = p->n_left;
nfree(l);
break;
case STASG: /* convert struct assignment to call memcpy */
l = p->n_left;
if (l->n_op == NAME && ISFTN(l->n_sp->stype))
break; /* struct return, do nothing */
/* first construct arg list */
p->n_left = buildtree(ADDROF, p->n_left, 0);
r = bcon(tsize(STRTY, p->n_df, p->n_ap)/SZCHAR);
p->n_left = buildtree(CM, p->n_left, p->n_right);
p->n_right = r;
p->n_op = CM;
p->n_type = INT;
r = block(NAME, NIL, NIL, INT, 0, 0);
r->n_sp = lookup(addname("memcpy"), SNORMAL);
if (r->n_sp->sclass == SNULL) {
r->n_sp->sclass = EXTERN;
r->n_sp->stype = INCREF(VOID+PTR)+(FTN-PTR);
}
r->n_type = r->n_sp->stype;
p = buildtree(CALL, r, p);
break;
case SCONV:
l = p->n_left;
if (l->n_op == ICON && ISPTR(l->n_type)) {
/* Do immediate cast here */
/* Should be common code */
q = l->n_sp;
l->n_sp = NULL;
l->n_type = UNSIGNED;
if (concast(l, p->n_type) == 0)
cerror("clocal");
p = nfree(p);
p->n_sp = q;
}
break;
case FORCE:
/* put return value in return reg */
p->n_op = ASSIGN;
p->n_right = p->n_left;
p->n_left = block(REG, NIL, NIL, p->n_type, 0, 0);
t = p->n_type;
if (ISITY(t))
t = t - (FIMAG-FLOAT);
p->n_left->n_rval = RETREG(t);
break;
}
#ifdef PCC_DEBUG
if (xdebug) {
printf("clocal end: %p\n", p);
fwalk(p, eprint, 0);
}
#endif
return(p);
}
