ref: 8726990cf563f72d91e1cb8335510d5a1d38ec02
dir: /sys/src/cmd/5c/cgen.c/
#include "gc.h" static void genasop(int, Node*, Node*, Node*); void cgen(Node *n, Node *nn) { cgenrel(n, nn, 0); } void cgenrel(Node *n, Node *nn, int inrel) { Node *l, *r; Prog *p1; Node nod, nod1, nod2, nod3, nod4; int o, t; long v, curs; if(debug['g']) { prtree(nn, "cgen lhs"); prtree(n, "cgen"); } if(n == Z || n->type == T) return; if(typesuv[n->type->etype]) { sugen(n, nn, n->type->width); return; } l = n->left; r = n->right; o = n->op; if(n->addable >= INDEXED) { if(nn == Z) { switch(o) { default: nullwarn(Z, Z); break; case OINDEX: nullwarn(l, r); break; } return; } gmove(n, nn); return; } curs = cursafe; if(n->complex >= FNX) if(l->complex >= FNX) if(r != Z && r->complex >= FNX) switch(o) { default: regret(&nod, r); cgen(r, &nod); regsalloc(&nod1, r); gmove(&nod, &nod1); regfree(&nod); nod = *n; nod.right = &nod1; cgen(&nod, nn); return; case OFUNC: case OCOMMA: case OANDAND: case OOROR: case OCOND: case ODOT: break; } switch(o) { default: diag(n, "unknown op in cgen: %O", o); break; case OAS: if(l->op == OBIT) goto bitas; if(l->addable >= INDEXED && l->complex < FNX) { if(nn != Z || r->addable < INDEXED) { if(r->complex >= FNX && nn == Z) regret(&nod, r); else regalloc(&nod, r, nn); cgen(r, &nod); gmove(&nod, l); if(nn != Z) gmove(&nod, nn); regfree(&nod); } else gmove(r, l); break; } if(l->complex >= r->complex) { reglcgen(&nod1, l, Z); if(r->addable >= INDEXED) { gmove(r, &nod1); if(nn != Z) gmove(r, nn); regfree(&nod1); break; } regalloc(&nod, r, nn); cgen(r, &nod); } else { regalloc(&nod, r, nn); cgen(r, &nod); reglcgen(&nod1, l, Z); } gmove(&nod, &nod1); regfree(&nod); regfree(&nod1); break; bitas: n = l->left; regalloc(&nod, r, nn); if(l->complex >= r->complex) { reglcgen(&nod1, n, Z); cgen(r, &nod); } else { cgen(r, &nod); reglcgen(&nod1, n, Z); } regalloc(&nod2, n, Z); gopcode(OAS, &nod1, Z, &nod2); bitstore(l, &nod, &nod1, &nod2, nn); break; case OBIT: if(nn == Z) { nullwarn(l, Z); break; } bitload(n, &nod, Z, Z, nn); gopcode(OAS, &nod, Z, nn); regfree(&nod); break; case ODIV: case OMOD: if(nn != Z) if((t = vlog(r)) >= 0) { /* signed div/mod by constant power of 2 */ cgen(l, nn); gopcode(OGE, nodconst(0), nn, Z); p1 = p; if(o == ODIV) { gopcode(OADD, nodconst((1<<t)-1), Z, nn); patch(p1, pc); gopcode(OASHR, nodconst(t), Z, nn); } else { gopcode(OSUB, nn, nodconst(0), nn); gopcode(OAND, nodconst((1<<t)-1), Z, nn); gopcode(OSUB, nn, nodconst(0), nn); gbranch(OGOTO); patch(p1, pc); p1 = p; gopcode(OAND, nodconst((1<<t)-1), Z, nn); patch(p1, pc); } break; } goto muldiv; case OSUB: if(nn != Z) if(l->op == OCONST) if(!typefd[n->type->etype]) { cgen(r, nn); gopcode(o, Z, l, nn); break; } case OADD: case OAND: case OOR: case OXOR: case OLSHR: case OASHL: case OASHR: /* * immediate operands */ if(nn != Z) if(r->op == OCONST) if(!typefd[n->type->etype]) { cgen(l, nn); if(r->vconst == 0) if(o != OAND) break; if(nn != Z) gopcode(o, r, Z, nn); break; } case OLMUL: case OLDIV: case OLMOD: case OMUL: muldiv: if(nn == Z) { nullwarn(l, r); break; } if(o == OMUL || o == OLMUL) { if(mulcon(n, nn)) break; } if(l->complex >= r->complex) { regalloc(&nod, l, nn); cgen(l, &nod); regalloc(&nod1, r, Z); cgen(r, &nod1); gopcode(o, &nod1, Z, &nod); } else { regalloc(&nod, r, nn); cgen(r, &nod); regalloc(&nod1, l, Z); cgen(l, &nod1); gopcode(o, &nod, &nod1, &nod); } gopcode(OAS, &nod, Z, nn); regfree(&nod); regfree(&nod1); break; case OASLSHR: case OASASHL: case OASASHR: case OASAND: case OASADD: case OASSUB: case OASXOR: case OASOR: if(l->op == OBIT) goto asbitop; if(r->op == OCONST) if(!typefd[r->type->etype]) if(!typefd[n->type->etype]) { if(l->addable < INDEXED) reglcgen(&nod2, l, Z); else nod2 = *l; regalloc(&nod, l, nn); gopcode(OAS, &nod2, Z, &nod); gopcode(o, r, Z, &nod); gopcode(OAS, &nod, Z, &nod2); regfree(&nod); if(l->addable < INDEXED) regfree(&nod2); break; } genasop(o, l, r, nn); break; case OASLMUL: case OASLDIV: case OASLMOD: case OASMUL: case OASDIV: case OASMOD: if(l->op == OBIT) goto asbitop; genasop(o, l, r, nn); break; asbitop: regalloc(&nod4, n, nn); if(l->complex >= r->complex) { bitload(l, &nod, &nod1, &nod2, &nod4); regalloc(&nod3, r, Z); cgen(r, &nod3); } else { regalloc(&nod3, r, Z); cgen(r, &nod3); bitload(l, &nod, &nod1, &nod2, &nod4); } gmove(&nod, &nod4); gopcode(o, &nod3, Z, &nod4); regfree(&nod3); gmove(&nod4, &nod); regfree(&nod4); bitstore(l, &nod, &nod1, &nod2, nn); break; case OADDR: if(nn == Z) { nullwarn(l, Z); break; } lcgen(l, nn); break; case OFUNC: l = uncomma(l); if(l->complex >= FNX) { if(l->op != OIND) diag(n, "bad function call"); regret(&nod, l->left); cgen(l->left, &nod); regsalloc(&nod1, l->left); gopcode(OAS, &nod, Z, &nod1); regfree(&nod); nod = *n; nod.left = &nod2; nod2 = *l; nod2.left = &nod1; nod2.complex = 1; cgen(&nod, nn); return; } if(REGARG >= 0) o = reg[REGARG]; gargs(r, &nod, &nod1); if(l->addable < INDEXED) { reglcgen(&nod, l, Z); gopcode(OFUNC, Z, Z, &nod); regfree(&nod); } else gopcode(OFUNC, Z, Z, l); if(REGARG >= 0) if(o != reg[REGARG]) reg[REGARG]--; if(nn != Z) { regret(&nod, n); gopcode(OAS, &nod, Z, nn); regfree(&nod); } break; case OIND: if(nn == Z) { nullwarn(l, Z); break; } regialloc(&nod, n, nn); r = l; while(r->op == OADD) r = r->right; if(sconst(r) && (v = r->vconst+nod.xoffset) > -4096 && v < 4096) { v = r->vconst; r->vconst = 0; cgen(l, &nod); nod.xoffset += v; r->vconst = v; } else cgen(l, &nod); regind(&nod, n); gopcode(OAS, &nod, Z, nn); regfree(&nod); break; case OEQ: case ONE: case OLE: case OLT: case OGE: case OGT: case OLO: case OLS: case OHI: case OHS: if(nn == Z) { nullwarn(l, r); break; } boolgen(n, 1, nn); break; case OANDAND: case OOROR: boolgen(n, 1, nn); if(nn == Z) patch(p, pc); break; case ONOT: if(nn == Z) { nullwarn(l, Z); break; } boolgen(n, 1, nn); break; case OCOMMA: cgen(l, Z); cgen(r, nn); break; case OCAST: if(nn == Z) { nullwarn(l, Z); break; } /* * convert from types l->n->nn */ if(nocast(l->type, n->type)) { if(nocast(n->type, nn->type)) { cgen(l, nn); break; } } regalloc(&nod, l, nn); cgen(l, &nod); regalloc(&nod1, n, &nod); if(inrel) gmover(&nod, &nod1); else gopcode(OAS, &nod, Z, &nod1); gopcode(OAS, &nod1, Z, nn); regfree(&nod1); regfree(&nod); break; case ODOT: sugen(l, nodrat, l->type->width); if(nn != Z) { warn(n, "non-interruptable temporary"); nod = *nodrat; if(!r || r->op != OCONST) { diag(n, "DOT and no offset"); break; } nod.xoffset += (long)r->vconst; nod.type = n->type; cgen(&nod, nn); } break; case OCOND: bcgen(l, 1); p1 = p; cgen(r->left, nn); gbranch(OGOTO); patch(p1, pc); p1 = p; cgen(r->right, nn); patch(p1, pc); break; case OPOSTINC: case OPOSTDEC: v = 1; if(l->type->etype == TIND) v = l->type->link->width; if(o == OPOSTDEC) v = -v; if(l->op == OBIT) goto bitinc; if(nn == Z) goto pre; if(l->addable < INDEXED) reglcgen(&nod2, l, Z); else nod2 = *l; regalloc(&nod, l, nn); gopcode(OAS, &nod2, Z, &nod); regalloc(&nod1, l, Z); if(typefd[l->type->etype]) { regalloc(&nod3, l, Z); if(v < 0) { gopcode(OAS, nodfconst(-v), Z, &nod3); gopcode(OSUB, &nod3, &nod, &nod1); } else { gopcode(OAS, nodfconst(v), Z, &nod3); gopcode(OADD, &nod3, &nod, &nod1); } regfree(&nod3); } else gopcode(OADD, nodconst(v), &nod, &nod1); gopcode(OAS, &nod1, Z, &nod2); regfree(&nod); regfree(&nod1); if(l->addable < INDEXED) regfree(&nod2); break; case OPREINC: case OPREDEC: v = 1; if(l->type->etype == TIND) v = l->type->link->width; if(o == OPREDEC) v = -v; if(l->op == OBIT) goto bitinc; pre: if(l->addable < INDEXED) reglcgen(&nod2, l, Z); else nod2 = *l; regalloc(&nod, l, nn); gopcode(OAS, &nod2, Z, &nod); if(typefd[l->type->etype]) { regalloc(&nod3, l, Z); if(v < 0) { gopcode(OAS, nodfconst(-v), Z, &nod3); gopcode(OSUB, &nod3, Z, &nod); } else { gopcode(OAS, nodfconst(v), Z, &nod3); gopcode(OADD, &nod3, Z, &nod); } regfree(&nod3); } else gopcode(OADD, nodconst(v), Z, &nod); gopcode(OAS, &nod, Z, &nod2); if(nn && l->op == ONAME) /* in x=++i, emit USED(i) */ gins(ANOP, l, Z); regfree(&nod); if(l->addable < INDEXED) regfree(&nod2); break; bitinc: if(nn != Z && (o == OPOSTINC || o == OPOSTDEC)) { bitload(l, &nod, &nod1, &nod2, Z); gopcode(OAS, &nod, Z, nn); gopcode(OADD, nodconst(v), Z, &nod); bitstore(l, &nod, &nod1, &nod2, Z); break; } bitload(l, &nod, &nod1, &nod2, nn); gopcode(OADD, nodconst(v), Z, &nod); bitstore(l, &nod, &nod1, &nod2, nn); break; } cursafe = curs; return; } static void genasop(int o, Node *l, Node *r, Node *nn) { Node nod, nod1, nod2; int hardleft; hardleft = l->addable < INDEXED || l->complex >= FNX; if(l->complex >= r->complex) { if(hardleft) reglcgen(&nod2, l, Z); else nod2 = *l; regalloc(&nod1, r, Z); cgen(r, &nod1); } else { regalloc(&nod1, r, Z); cgen(r, &nod1); if(hardleft) reglcgen(&nod2, l, Z); else nod2 = *l; } if(nod1.type == nod2.type || !typefd[nod1.type->etype]) regalloc(&nod, &nod2, nn); else regalloc(&nod, &nod1, Z); gmove(&nod2, &nod); gopcode(o, &nod1, Z, &nod); gmove(&nod, &nod2); if(nn != Z) gmove(&nod2, nn); regfree(&nod); regfree(&nod1); if(hardleft) regfree(&nod2); } void reglcgen(Node *t, Node *n, Node *nn) { Node *r; long v; regialloc(t, n, nn); if(n->op == OIND) { r = n->left; while(r->op == OADD) r = r->right; if(sconst(r) && (v = r->vconst+t->xoffset) > -4096 && v < 4096) { v = r->vconst; r->vconst = 0; lcgen(n, t); t->xoffset += v; r->vconst = v; regind(t, n); return; } } else if(n->op == OINDREG) { if((v = n->xoffset) > -4096 && v < 4096) { n->op = OREGISTER; cgen(n, t); t->xoffset += v; n->op = OINDREG; regind(t, n); return; } } lcgen(n, t); regind(t, n); } void reglpcgen(Node *n, Node *nn, int f) { Type *t; t = nn->type; nn->type = types[TLONG]; if(f) reglcgen(n, nn, Z); else { regialloc(n, nn, Z); lcgen(nn, n); regind(n, nn); } nn->type = t; } void lcgen(Node *n, Node *nn) { Prog *p1; Node nod; if(debug['g']) { prtree(nn, "lcgen lhs"); prtree(n, "lcgen"); } if(n == Z || n->type == T) return; if(nn == Z) { nn = &nod; regalloc(&nod, n, Z); } switch(n->op) { default: if(n->addable < INDEXED) { diag(n, "unknown op in lcgen: %O", n->op); break; } nod = *n; nod.op = OADDR; nod.left = n; nod.right = Z; nod.type = types[TIND]; gopcode(OAS, &nod, Z, nn); break; case OCOMMA: cgen(n->left, n->left); lcgen(n->right, nn); break; case OIND: cgen(n->left, nn); break; case OCOND: bcgen(n->left, 1); p1 = p; lcgen(n->right->left, nn); gbranch(OGOTO); patch(p1, pc); p1 = p; lcgen(n->right->right, nn); patch(p1, pc); break; } } void bcgen(Node *n, int true) { if(n->type == T) gbranch(OGOTO); else boolgen(n, true, Z); } void boolgen(Node *n, int true, Node *nn) { int o; Prog *p1, *p2; Node *l, *r, nod, nod1; long curs; if(debug['g']) { prtree(nn, "boolgen lhs"); prtree(n, "boolgen"); } curs = cursafe; l = n->left; r = n->right; switch(n->op) { default: regalloc(&nod, n, nn); cgen(n, &nod); o = ONE; if(true) o = comrel[relindex(o)]; if(typefd[n->type->etype]) { gopcode(true ? o | BTRUE : o, nodfconst(0), &nod, Z); } else gopcode(o, nodconst(0), &nod, Z); regfree(&nod); goto com; case OCONST: o = vconst(n); if(!true) o = !o; gbranch(OGOTO); if(o) { p1 = p; gbranch(OGOTO); patch(p1, pc); } goto com; case OCOMMA: cgen(l, Z); boolgen(r, true, nn); break; case ONOT: boolgen(l, !true, nn); break; case OCOND: bcgen(l, 1); p1 = p; bcgen(r->left, true); p2 = p; gbranch(OGOTO); patch(p1, pc); p1 = p; bcgen(r->right, !true); patch(p2, pc); p2 = p; gbranch(OGOTO); patch(p1, pc); patch(p2, pc); goto com; case OANDAND: if(!true) goto caseor; caseand: bcgen(l, true); p1 = p; bcgen(r, !true); p2 = p; patch(p1, pc); gbranch(OGOTO); patch(p2, pc); goto com; case OOROR: if(!true) goto caseand; caseor: bcgen(l, !true); p1 = p; bcgen(r, !true); p2 = p; gbranch(OGOTO); patch(p1, pc); patch(p2, pc); goto com; case OEQ: case ONE: case OLE: case OLT: case OGE: case OGT: case OHI: case OHS: case OLO: case OLS: o = n->op; if(true) o = comrel[relindex(o)]; if(l->complex >= FNX && r->complex >= FNX) { regret(&nod, r); cgenrel(r, &nod, 1); regsalloc(&nod1, r); gopcode(OAS, &nod, Z, &nod1); regfree(&nod); nod = *n; nod.right = &nod1; boolgen(&nod, true, nn); break; } if(sconst(l)) { regalloc(&nod, r, nn); cgenrel(r, &nod, 1); o = invrel[relindex(o)]; gopcode(true ? o | BTRUE : o, l, &nod, Z); regfree(&nod); goto com; } if(sconst(r)) { regalloc(&nod, l, nn); cgenrel(l, &nod, 1); gopcode(true ? o | BTRUE : o, r, &nod, Z); regfree(&nod); goto com; } if(l->complex >= r->complex) { regalloc(&nod1, l, nn); cgenrel(l, &nod1, 1); regalloc(&nod, r, Z); cgenrel(r, &nod, 1); } else { regalloc(&nod, r, nn); cgenrel(r, &nod, 1); regalloc(&nod1, l, Z); cgenrel(l, &nod1, 1); } gopcode(true ? o | BTRUE : o, &nod, &nod1, Z); regfree(&nod); regfree(&nod1); com: if(nn != Z) { p1 = p; gopcode(OAS, nodconst(1), Z, nn); gbranch(OGOTO); p2 = p; patch(p1, pc); gopcode(OAS, nodconst(0), Z, nn); patch(p2, pc); } break; } cursafe = curs; } void sugen(Node *n, Node *nn, long w) { Prog *p1; Node nod0, nod1, nod2, nod3, nod4, *l, *r; Type *t; long pc1; int i, m, c; if(n == Z || n->type == T) return; if(debug['g']) { prtree(nn, "sugen lhs"); prtree(n, "sugen"); } if(nn == nodrat) if(w > nrathole) nrathole = w; switch(n->op) { case OIND: if(nn == Z) { nullwarn(n->left, Z); break; } default: goto copy; case OCONST: if(n->type && typev[n->type->etype]) { if(nn == Z) { nullwarn(n->left, Z); break; } t = nn->type; nn->type = types[TLONG]; reglcgen(&nod1, nn, Z); nn->type = t; if(align(0, types[TCHAR], Aarg1)) /* isbigendian */ gopcode(OAS, nod32const(n->vconst>>32), Z, &nod1); else gopcode(OAS, nod32const(n->vconst), Z, &nod1); nod1.xoffset += SZ_LONG; if(align(0, types[TCHAR], Aarg1)) /* isbigendian */ gopcode(OAS, nod32const(n->vconst), Z, &nod1); else gopcode(OAS, nod32const(n->vconst>>32), Z, &nod1); regfree(&nod1); break; } goto copy; case ODOT: l = n->left; sugen(l, nodrat, l->type->width); if(nn != Z) { warn(n, "non-interruptable temporary"); nod1 = *nodrat; r = n->right; if(!r || r->op != OCONST) { diag(n, "DOT and no offset"); break; } nod1.xoffset += (long)r->vconst; nod1.type = n->type; sugen(&nod1, nn, w); } break; case OSTRUCT: /* * rewrite so lhs has no side effects */ if(nn != Z && side(nn)) { nod1 = *n; nod1.type = typ(TIND, n->type); regalloc(&nod2, &nod1, Z); lcgen(nn, &nod2); regsalloc(&nod0, &nod1); gopcode(OAS, &nod2, Z, &nod0); regfree(&nod2); nod1 = *n; nod1.op = OIND; nod1.left = &nod0; nod1.right = Z; nod1.complex = 1; sugen(n, &nod1, w); return; } r = n->left; for(t = n->type->link; t != T; t = t->down) { l = r; if(r->op == OLIST) { l = r->left; r = r->right; } if(nn == Z) { cgen(l, nn); continue; } /* * hand craft *(&nn + o) = l */ nod0 = znode; nod0.op = OAS; nod0.type = t; nod0.left = &nod1; nod0.right = l; nod1 = znode; nod1.op = OIND; nod1.type = t; nod1.left = &nod2; nod2 = znode; nod2.op = OADD; nod2.type = typ(TIND, t); nod2.left = &nod3; nod2.right = &nod4; nod3 = znode; nod3.op = OADDR; nod3.type = nod2.type; nod3.left = nn; nod4 = znode; nod4.op = OCONST; nod4.type = nod2.type; nod4.vconst = t->offset; ccom(&nod0); acom(&nod0); xcom(&nod0); nod0.addable = 0; cgen(&nod0, Z); } break; case OAS: if(nn == Z) { if(n->addable < INDEXED) sugen(n->right, n->left, w); break; } sugen(n->right, nodrat, w); warn(n, "non-interruptable temporary"); sugen(nodrat, n->left, w); sugen(nodrat, nn, w); break; case OFUNC: if(nn == Z) { sugen(n, nodrat, w); break; } if(nn->op != OIND) { nn = new1(OADDR, nn, Z); nn->type = types[TIND]; nn->addable = 0; } else nn = nn->left; n = new(OFUNC, n->left, new(OLIST, nn, n->right)); n->complex = FNX; n->type = types[TVOID]; n->left->type = types[TVOID]; cgen(n, Z); break; case OCOND: bcgen(n->left, 1); p1 = p; sugen(n->right->left, nn, w); gbranch(OGOTO); patch(p1, pc); p1 = p; sugen(n->right->right, nn, w); patch(p1, pc); break; case OCOMMA: cgen(n->left, Z); sugen(n->right, nn, w); break; } return; copy: if(nn == Z) return; if(n->complex >= FNX && nn->complex >= FNX) { t = nn->type; nn->type = types[TLONG]; regialloc(&nod1, nn, Z); lcgen(nn, &nod1); regsalloc(&nod2, nn); nn->type = t; gopcode(OAS, &nod1, Z, &nod2); regfree(&nod1); nod2.type = typ(TIND, t); nod1 = nod2; nod1.op = OIND; nod1.left = &nod2; nod1.right = Z; nod1.complex = 1; nod1.type = t; sugen(n, &nod1, w); return; } w /= SZ_LONG; if(w <= 2) { if(n->complex > nn->complex) { reglpcgen(&nod1, n, 1); reglpcgen(&nod2, nn, 1); } else { reglpcgen(&nod2, nn, 1); reglpcgen(&nod1, n, 1); } regalloc(&nod3, ®node, Z); regalloc(&nod4, ®node, Z); if(nod3.reg > nod4.reg){ /* code below assumes nod3 loaded first */ Node t = nod3; nod3 = nod4; nod4 = t; } nod0 = *nodconst((1<<nod3.reg)|(1<<nod4.reg)); if(w == 2 && nod1.xoffset == 0) gmovm(&nod1, &nod0, 0); else { gmove(&nod1, &nod3); if(w == 2) { nod1.xoffset += SZ_LONG; gmove(&nod1, &nod4); } } if(w == 2 && nod2.xoffset == 0) gmovm(&nod0, &nod2, 0); else { gmove(&nod3, &nod2); if(w == 2) { nod2.xoffset += SZ_LONG; gmove(&nod4, &nod2); } } regfree(&nod1); regfree(&nod2); regfree(&nod3); regfree(&nod4); return; } if(n->complex > nn->complex) { reglpcgen(&nod1, n, 0); reglpcgen(&nod2, nn, 0); } else { reglpcgen(&nod2, nn, 0); reglpcgen(&nod1, n, 0); } m = 0; for(c = 0; c < w && c < 4; c++) { i = tmpreg(); if (i == 0) break; reg[i]++; m |= 1<<i; } nod4 = *(nodconst(m)); if(w < 3*c) { for (; w>c; w-=c) { gmovm(&nod1, &nod4, 1); gmovm(&nod4, &nod2, 1); } goto out; } regalloc(&nod3, ®node, Z); gopcode(OAS, nodconst(w/c), Z, &nod3); w %= c; pc1 = pc; gmovm(&nod1, &nod4, 1); gmovm(&nod4, &nod2, 1); gopcode(OSUB, nodconst(1), Z, &nod3); gopcode(OEQ, nodconst(0), &nod3, Z); p->as = ABGT; patch(p, pc1); regfree(&nod3); out: if (w) { i = 0; while (c>w) { while ((m&(1<<i)) == 0) i++; m &= ~(1<<i); reg[i] = 0; c--; i++; } nod4.vconst = m; gmovm(&nod1, &nod4, 0); gmovm(&nod4, &nod2, 0); } i = 0; do { while ((m&(1<<i)) == 0) i++; reg[i] = 0; c--; i++; } while (c>0); regfree(&nod1); regfree(&nod2); }