1 /*
2 * Copyright (c) 2014, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "opto/addnode.hpp"
27 #include "opto/callnode.hpp"
28 #include "opto/castnode.hpp"
29 #include "opto/connode.hpp"
30 #include "opto/graphKit.hpp"
31 #include "opto/inlinetypenode.hpp"
32 #include "opto/matcher.hpp"
33 #include "opto/phaseX.hpp"
34 #include "opto/rootnode.hpp"
35 #include "opto/subnode.hpp"
36 #include "opto/type.hpp"
37 #include "castnode.hpp"
38 #include "utilities/checkedCast.hpp"
39
40 //=============================================================================
41 // If input is already higher or equal to cast type, then this is an identity.
42 Node* ConstraintCastNode::Identity(PhaseGVN* phase) {
43 if (_dependency == UnconditionalDependency) {
44 return this;
45 }
46 Node* dom = dominating_cast(phase, phase);
47 if (dom != nullptr) {
48 return dom;
49 }
50 return higher_equal_types(phase, in(1)) ? in(1) : this;
51 }
52
53 //------------------------------Value------------------------------------------
54 // Take 'join' of input and cast-up type
55 const Type* ConstraintCastNode::Value(PhaseGVN* phase) const {
56 if (in(0) && phase->type(in(0)) == Type::TOP) return Type::TOP;
57
58 const Type* in_type = phase->type(in(1));
59 const Type* ft = in_type->filter_speculative(_type);
60
61 // Check if both _type and in_type had a speculative type, but for the just
62 // computed ft the speculative type was dropped.
63 if (ft->speculative() == nullptr &&
64 _type->speculative() != nullptr &&
65 in_type->speculative() != nullptr) {
66 // Speculative type may have disagreed between cast and input, and was
67 // dropped in filtering. Recompute so that ft can take speculative type
68 // of in_type. If we did not do it now, a subsequent ::Value call would
69 // do it, and violate idempotence of ::Value.
70 ft = in_type->filter_speculative(ft);
71 }
72
73 #ifdef ASSERT
74 // Previous versions of this function had some special case logic,
75 // which is no longer necessary. Make sure of the required effects.
76 switch (Opcode()) {
77 case Op_CastII:
78 {
79 if (in_type == Type::TOP) {
80 assert(ft == Type::TOP, "special case #1");
81 }
82 const Type* rt = in_type->join_speculative(_type);
83 if (rt->empty()) {
84 assert(ft == Type::TOP, "special case #2");
85 }
86 break;
87 }
88 case Op_CastPP:
89 if (in_type == TypePtr::NULL_PTR &&
90 _type->isa_ptr() && _type->is_ptr()->_ptr == TypePtr::NotNull) {
91 assert(ft == Type::TOP, "special case #3");
92 break;
93 }
94 }
95 #endif //ASSERT
96
97 return ft;
98 }
99
100 //------------------------------Ideal------------------------------------------
101 // Return a node which is more "ideal" than the current node. Strip out
102 // control copies
103 Node *ConstraintCastNode::Ideal(PhaseGVN *phase, bool can_reshape) {
104 if (in(0) && remove_dead_region(phase, can_reshape)) {
105 return this;
106 }
107
108 // Push cast through InlineTypeNode
109 InlineTypeNode* vt = in(1)->isa_InlineType();
110 if (vt != nullptr && phase->type(vt)->filter_speculative(_type) != Type::TOP) {
111 // TODO 8325106 Can we avoid cloning?
112 Node* cast = clone();
113 cast->set_req(1, vt->get_oop());
114 vt = vt->clone()->as_InlineType();
115 if (!_type->maybe_null()) {
116 vt->as_InlineType()->set_is_init(*phase);
117 }
118 vt->set_oop(*phase, phase->transform(cast));
119 return vt;
120 }
121
122 return nullptr;
123 }
124
125 uint ConstraintCastNode::hash() const {
126 return TypeNode::hash() + (int)_dependency + (_extra_types != nullptr ? _extra_types->hash() : 0);
127 }
128
129 bool ConstraintCastNode::cmp(const Node &n) const {
130 if (!TypeNode::cmp(n)) {
131 return false;
132 }
133 ConstraintCastNode& cast = (ConstraintCastNode&) n;
134 if (cast._dependency != _dependency) {
135 return false;
136 }
137 if (_extra_types == nullptr || cast._extra_types == nullptr) {
138 return _extra_types == cast._extra_types;
139 }
140 return _extra_types->eq(cast._extra_types);
141 }
142
143 uint ConstraintCastNode::size_of() const {
144 return sizeof(*this);
145 }
146
147 Node* ConstraintCastNode::make_cast(int opcode, Node* c, Node* n, const Type* t, DependencyType dependency,
148 const TypeTuple* extra_types) {
149 switch(opcode) {
150 case Op_CastII: {
151 Node* cast = new CastIINode(n, t, dependency, false, extra_types);
152 cast->set_req(0, c);
153 return cast;
154 }
155 case Op_CastLL: {
156 Node* cast = new CastLLNode(n, t, dependency, extra_types);
157 cast->set_req(0, c);
158 return cast;
159 }
160 case Op_CastPP: {
161 Node* cast = new CastPPNode(n, t, dependency, extra_types);
162 cast->set_req(0, c);
163 return cast;
164 }
165 case Op_CastFF: {
166 Node* cast = new CastFFNode(n, t, dependency, extra_types);
167 cast->set_req(0, c);
168 return cast;
169 }
170 case Op_CastDD: {
171 Node* cast = new CastDDNode(n, t, dependency, extra_types);
172 cast->set_req(0, c);
173 return cast;
174 }
175 case Op_CastVV: {
176 Node* cast = new CastVVNode(n, t, dependency, extra_types);
177 cast->set_req(0, c);
178 return cast;
179 }
180 case Op_CheckCastPP: return new CheckCastPPNode(c, n, t, dependency, extra_types);
181 default:
182 fatal("Bad opcode %d", opcode);
183 }
184 return nullptr;
185 }
186
187 Node* ConstraintCastNode::make(Node* c, Node *n, const Type *t, DependencyType dependency, BasicType bt) {
188 switch(bt) {
189 case T_INT: {
190 return make_cast(Op_CastII, c, n, t, dependency, nullptr);
191 }
192 case T_LONG: {
193 return make_cast(Op_CastLL, c, n, t, dependency, nullptr);
194 }
195 default:
196 fatal("Bad basic type %s", type2name(bt));
197 }
198 return nullptr;
199 }
200
201 TypeNode* ConstraintCastNode::dominating_cast(PhaseGVN* gvn, PhaseTransform* pt) const {
202 if (_dependency == UnconditionalDependency) {
203 return nullptr;
204 }
205 Node* val = in(1);
206 Node* ctl = in(0);
207 int opc = Opcode();
208 if (ctl == nullptr) {
209 return nullptr;
210 }
211 // Range check CastIIs may all end up under a single range check and
212 // in that case only the narrower CastII would be kept by the code
213 // below which would be incorrect.
214 if (is_CastII() && as_CastII()->has_range_check()) {
215 return nullptr;
216 }
217 if (type()->isa_rawptr() && (gvn->type_or_null(val) == nullptr || gvn->type(val)->isa_oopptr())) {
218 return nullptr;
219 }
220 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
221 Node* u = val->fast_out(i);
222 if (u != this &&
223 u->outcnt() > 0 &&
224 u->Opcode() == opc &&
225 u->in(0) != nullptr &&
226 higher_equal_types(gvn, u)) {
227 if (pt->is_dominator(u->in(0), ctl)) {
228 return u->as_Type();
229 }
230 if (is_CheckCastPP() && u->in(1)->is_Proj() && u->in(1)->in(0)->is_Allocate() &&
231 u->in(0)->is_Proj() && u->in(0)->in(0)->is_Initialize() &&
232 u->in(1)->in(0)->as_Allocate()->initialization() == u->in(0)->in(0)) {
233 // CheckCastPP following an allocation always dominates all
234 // use of the allocation result
235 return u->as_Type();
236 }
237 }
238 }
239 return nullptr;
240 }
241
242 bool ConstraintCastNode::higher_equal_types(PhaseGVN* phase, const Node* other) const {
243 const Type* t = phase->type(other);
244 if (!t->higher_equal_speculative(type())) {
245 return false;
246 }
247 if (_extra_types != nullptr) {
248 for (uint i = 0; i < _extra_types->cnt(); ++i) {
249 if (!t->higher_equal_speculative(_extra_types->field_at(i))) {
250 return false;
251 }
252 }
253 }
254 return true;
255 }
256
257 #ifndef PRODUCT
258 void ConstraintCastNode::dump_spec(outputStream *st) const {
259 TypeNode::dump_spec(st);
260 if (_extra_types != nullptr) {
261 st->print(" extra types: ");
262 _extra_types->dump_on(st);
263 }
264 if (_dependency != RegularDependency) {
265 st->print(" %s dependency", _dependency == StrongDependency ? "strong" : "unconditional");
266 }
267 }
268 #endif
269
270 const Type* CastIINode::Value(PhaseGVN* phase) const {
271 const Type *res = ConstraintCastNode::Value(phase);
272 if (res == Type::TOP) {
273 return Type::TOP;
274 }
275 assert(res->isa_int(), "res must be int");
276
277 // Similar to ConvI2LNode::Value() for the same reasons
278 // see if we can remove type assertion after loop opts
279 // But here we have to pay extra attention:
280 // Do not narrow the type of range check dependent CastIINodes to
281 // avoid corruption of the graph if a CastII is replaced by TOP but
282 // the corresponding range check is not removed.
283 if (!_range_check_dependency) {
284 res = widen_type(phase, res, T_INT);
285 }
286
287 return res;
288 }
289
290 static Node* find_or_make_integer_cast(PhaseIterGVN* igvn, Node* parent, Node* control, const TypeInteger* type, ConstraintCastNode::DependencyType dependency, BasicType bt) {
291 Node* n = ConstraintCastNode::make(control, parent, type, dependency, bt);
292 Node* existing = igvn->hash_find_insert(n);
293 if (existing != nullptr) {
294 n->destruct(igvn);
295 return existing;
296 }
297 return igvn->register_new_node_with_optimizer(n);
298 }
299
300 Node *CastIINode::Ideal(PhaseGVN *phase, bool can_reshape) {
301 Node* progress = ConstraintCastNode::Ideal(phase, can_reshape);
302 if (progress != nullptr) {
303 return progress;
304 }
305 if (can_reshape && !_range_check_dependency && !phase->C->post_loop_opts_phase()) {
306 // makes sure we run ::Value to potentially remove type assertion after loop opts
307 phase->C->record_for_post_loop_opts_igvn(this);
308 }
309 if (!_range_check_dependency) {
310 return optimize_integer_cast(phase, T_INT);
311 }
312 return nullptr;
313 }
314
315 Node* CastIINode::Identity(PhaseGVN* phase) {
316 Node* progress = ConstraintCastNode::Identity(phase);
317 if (progress != this) {
318 return progress;
319 }
320 if (_range_check_dependency) {
321 if (phase->C->post_loop_opts_phase()) {
322 return this->in(1);
323 } else {
324 phase->C->record_for_post_loop_opts_igvn(this);
325 }
326 }
327 return this;
328 }
329
330 bool CastIINode::cmp(const Node &n) const {
331 return ConstraintCastNode::cmp(n) && ((CastIINode&)n)._range_check_dependency == _range_check_dependency;
332 }
333
334 uint CastIINode::size_of() const {
335 return sizeof(*this);
336 }
337
338 #ifndef PRODUCT
339 void CastIINode::dump_spec(outputStream* st) const {
340 ConstraintCastNode::dump_spec(st);
341 if (_range_check_dependency) {
342 st->print(" range check dependency");
343 }
344 }
345 #endif
346
347 const Type* CastLLNode::Value(PhaseGVN* phase) const {
348 const Type* res = ConstraintCastNode::Value(phase);
349 if (res == Type::TOP) {
350 return Type::TOP;
351 }
352 assert(res->isa_long(), "res must be long");
353
354 return widen_type(phase, res, T_LONG);
355 }
356
357 Node* CastLLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
358 Node* progress = ConstraintCastNode::Ideal(phase, can_reshape);
359 if (progress != nullptr) {
360 return progress;
361 }
362 if (!phase->C->post_loop_opts_phase()) {
363 // makes sure we run ::Value to potentially remove type assertion after loop opts
364 phase->C->record_for_post_loop_opts_igvn(this);
365 }
366 // transform (CastLL (ConvI2L ..)) into (ConvI2L (CastII ..)) if the type of the CastLL is narrower than the type of
367 // the ConvI2L.
368 Node* in1 = in(1);
369 if (in1 != nullptr && in1->Opcode() == Op_ConvI2L) {
370 const Type* t = Value(phase);
371 const Type* t_in = phase->type(in1);
372 if (t != Type::TOP && t_in != Type::TOP) {
373 const TypeLong* tl = t->is_long();
374 const TypeLong* t_in_l = t_in->is_long();
375 assert(tl->_lo >= t_in_l->_lo && tl->_hi <= t_in_l->_hi, "CastLL type should be narrower than or equal to the type of its input");
376 assert((tl != t_in_l) == (tl->_lo > t_in_l->_lo || tl->_hi < t_in_l->_hi), "if type differs then this nodes's type must be narrower");
377 if (tl != t_in_l) {
378 const TypeInt* ti = TypeInt::make(checked_cast<jint>(tl->_lo), checked_cast<jint>(tl->_hi), tl->_widen);
379 Node* castii = phase->transform(new CastIINode(in(0), in1->in(1), ti));
380 Node* convi2l = in1->clone();
381 convi2l->set_req(1, castii);
382 return convi2l;
383 }
384 }
385 }
386 return optimize_integer_cast(phase, T_LONG);
387 }
388
389 //=============================================================================
390 //------------------------------Identity---------------------------------------
391 // If input is already higher or equal to cast type, then this is an identity.
392 Node* CheckCastPPNode::Identity(PhaseGVN* phase) {
393 if (in(1)->is_InlineType() && _type->isa_instptr() && phase->type(in(1))->inline_klass()->is_subtype_of(_type->is_instptr()->instance_klass())) {
394 return in(1);
395 }
396 return ConstraintCastNode::Identity(phase);
397 }
398
399 //------------------------------Value------------------------------------------
400 // Take 'join' of input and cast-up type, unless working with an Interface
401 const Type* CheckCastPPNode::Value(PhaseGVN* phase) const {
402 if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP;
403
404 const Type *inn = phase->type(in(1));
405 if( inn == Type::TOP ) return Type::TOP; // No information yet
406
407 if (inn->isa_oopptr() && _type->isa_oopptr()) {
408 return ConstraintCastNode::Value(phase);
409 }
410
411 const TypePtr *in_type = inn->isa_ptr();
412 const TypePtr *my_type = _type->isa_ptr();
413 const Type *result = _type;
414 if (in_type != nullptr && my_type != nullptr) {
415 // TODO 8302672
416 if (!StressReflectiveCode && my_type->isa_aryptr() && in_type->isa_aryptr()) {
417 // Propagate array properties (not flat/null-free)
418 // Don't do this when StressReflectiveCode is enabled because it might lead to
419 // a dying data path while the corresponding flat/null-free check is not folded.
420 my_type = my_type->is_aryptr()->update_properties(in_type->is_aryptr());
421 if (my_type == nullptr) {
422 return Type::TOP; // Inconsistent properties
423 }
424 }
425 TypePtr::PTR in_ptr = in_type->ptr();
426 if (in_ptr == TypePtr::Null) {
427 result = in_type;
428 } else if (in_ptr != TypePtr::Constant) {
429 result = my_type->cast_to_ptr_type(my_type->join_ptr(in_ptr));
430 }
431 }
432
433 return result;
434 }
435
436 //=============================================================================
437 //------------------------------Value------------------------------------------
438 const Type* CastX2PNode::Value(PhaseGVN* phase) const {
439 const Type* t = phase->type(in(1));
440 if (t == Type::TOP) return Type::TOP;
441 if (t->base() == Type_X && t->singleton()) {
442 uintptr_t bits = (uintptr_t) t->is_intptr_t()->get_con();
443 if (bits == 0) return TypePtr::NULL_PTR;
444 return TypeRawPtr::make((address) bits);
445 }
446 return CastX2PNode::bottom_type();
447 }
448
449 //------------------------------Idealize---------------------------------------
450 static inline bool fits_in_int(const Type* t, bool but_not_min_int = false) {
451 if (t == Type::TOP) return false;
452 const TypeX* tl = t->is_intptr_t();
453 jint lo = min_jint;
454 jint hi = max_jint;
455 if (but_not_min_int) ++lo; // caller wants to negate the value w/o overflow
456 return (tl->_lo >= lo) && (tl->_hi <= hi);
457 }
458
459 static inline Node* addP_of_X2P(PhaseGVN *phase,
460 Node* base,
461 Node* dispX,
462 bool negate = false) {
463 if (negate) {
464 dispX = phase->transform(new SubXNode(phase->MakeConX(0), dispX));
465 }
466 return new AddPNode(phase->C->top(),
467 phase->transform(new CastX2PNode(base)),
468 dispX);
469 }
470
471 Node *CastX2PNode::Ideal(PhaseGVN *phase, bool can_reshape) {
472 // convert CastX2P(AddX(x, y)) to AddP(CastX2P(x), y) if y fits in an int
473 int op = in(1)->Opcode();
474 Node* x;
475 Node* y;
476 switch (op) {
477 case Op_SubX:
478 x = in(1)->in(1);
479 // Avoid ideal transformations ping-pong between this and AddP for raw pointers.
480 if (phase->find_intptr_t_con(x, -1) == 0)
481 break;
482 y = in(1)->in(2);
483 if (fits_in_int(phase->type(y), true)) {
484 return addP_of_X2P(phase, x, y, true);
485 }
486 break;
487 case Op_AddX:
488 x = in(1)->in(1);
489 y = in(1)->in(2);
490 if (fits_in_int(phase->type(y))) {
491 return addP_of_X2P(phase, x, y);
492 }
493 if (fits_in_int(phase->type(x))) {
494 return addP_of_X2P(phase, y, x);
495 }
496 break;
497 }
498 return nullptr;
499 }
500
501 //------------------------------Identity---------------------------------------
502 Node* CastX2PNode::Identity(PhaseGVN* phase) {
503 if (in(1)->Opcode() == Op_CastP2X) return in(1)->in(1);
504 return this;
505 }
506
507 //=============================================================================
508 //------------------------------Value------------------------------------------
509 const Type* CastP2XNode::Value(PhaseGVN* phase) const {
510 const Type* t = phase->type(in(1));
511 if (t == Type::TOP) return Type::TOP;
512 if (t->base() == Type::RawPtr && t->singleton()) {
513 uintptr_t bits = (uintptr_t) t->is_rawptr()->get_con();
514 return TypeX::make(bits);
515 }
516
517 if (t->is_zero_type() || !t->maybe_null()) {
518 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
519 Node* u = fast_out(i);
520 if (u->Opcode() == Op_OrL) {
521 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
522 Node* cmp = u->fast_out(j);
523 if (cmp->Opcode() == Op_CmpL) {
524 // Give CmpL a chance to get optimized
525 phase->record_for_igvn(cmp);
526 }
527 }
528 }
529 }
530 }
531
532 return CastP2XNode::bottom_type();
533 }
534
535 Node *CastP2XNode::Ideal(PhaseGVN *phase, bool can_reshape) {
536 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : nullptr;
537 }
538
539 //------------------------------Identity---------------------------------------
540 Node* CastP2XNode::Identity(PhaseGVN* phase) {
541 if (in(1)->Opcode() == Op_CastX2P) return in(1)->in(1);
542 return this;
543 }
544
545 Node* ConstraintCastNode::make_cast_for_type(Node* c, Node* in, const Type* type, DependencyType dependency,
546 const TypeTuple* types) {
547 Node* cast= nullptr;
548 if (type->isa_int()) {
549 cast = make_cast(Op_CastII, c, in, type, dependency, types);
550 } else if (type->isa_long()) {
551 cast = make_cast(Op_CastLL, c, in, type, dependency, types);
552 } else if (type->isa_float()) {
553 cast = make_cast(Op_CastFF, c, in, type, dependency, types);
554 } else if (type->isa_double()) {
555 cast = make_cast(Op_CastDD, c, in, type, dependency, types);
556 } else if (type->isa_vect()) {
557 cast = make_cast(Op_CastVV, c, in, type, dependency, types);
558 } else if (type->isa_ptr()) {
559 cast = make_cast(Op_CastPP, c, in, type, dependency, types);
560 }
561 return cast;
562 }
563
564 Node* ConstraintCastNode::optimize_integer_cast(PhaseGVN* phase, BasicType bt) {
565 PhaseIterGVN *igvn = phase->is_IterGVN();
566 const TypeInteger* this_type = this->type()->is_integer(bt);
567 Node* z = in(1);
568 const TypeInteger* rx = nullptr;
569 const TypeInteger* ry = nullptr;
570 // Similar to ConvI2LNode::Ideal() for the same reasons
571 if (Compile::push_thru_add(phase, z, this_type, rx, ry, bt, bt)) {
572 if (igvn == nullptr) {
573 // Postpone this optimization to iterative GVN, where we can handle deep
574 // AddI chains without an exponential number of recursive Ideal() calls.
575 phase->record_for_igvn(this);
576 return nullptr;
577 }
578 int op = z->Opcode();
579 Node* x = z->in(1);
580 Node* y = z->in(2);
581
582 Node* cx = find_or_make_integer_cast(igvn, x, in(0), rx, _dependency, bt);
583 Node* cy = find_or_make_integer_cast(igvn, y, in(0), ry, _dependency, bt);
584 if (op == Op_Add(bt)) {
585 return AddNode::make(cx, cy, bt);
586 } else {
587 assert(op == Op_Sub(bt), "");
588 return SubNode::make(cx, cy, bt);
589 }
590 return nullptr;
591 }
592 return nullptr;
593 }
594
595 const Type* ConstraintCastNode::widen_type(const PhaseGVN* phase, const Type* res, BasicType bt) const {
596 if (!phase->C->post_loop_opts_phase()) {
597 return res;
598 }
599 const TypeInteger* this_type = res->is_integer(bt);
600 const TypeInteger* in_type = phase->type(in(1))->isa_integer(bt);
601 if (in_type != nullptr &&
602 (in_type->lo_as_long() != this_type->lo_as_long() ||
603 in_type->hi_as_long() != this_type->hi_as_long())) {
604 jlong lo1 = this_type->lo_as_long();
605 jlong hi1 = this_type->hi_as_long();
606 int w1 = this_type->_widen;
607 if (lo1 >= 0) {
608 // Keep a range assertion of >=0.
609 lo1 = 0; hi1 = max_signed_integer(bt);
610 } else if (hi1 < 0) {
611 // Keep a range assertion of <0.
612 lo1 = min_signed_integer(bt); hi1 = -1;
613 } else {
614 lo1 = min_signed_integer(bt); hi1 = max_signed_integer(bt);
615 }
616 return TypeInteger::make(MAX2(in_type->lo_as_long(), lo1),
617 MIN2(in_type->hi_as_long(), hi1),
618 MAX2((int)in_type->_widen, w1), bt);
619 }
620 return res;
621 }