1 /*
2 * Copyright (c) 2014, 2025, 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 "opto/addnode.hpp"
26 #include "opto/callnode.hpp"
27 #include "opto/castnode.hpp"
28 #include "opto/connode.hpp"
29 #include "opto/graphKit.hpp"
30 #include "opto/inlinetypenode.hpp"
31 #include "opto/matcher.hpp"
32 #include "opto/phaseX.hpp"
33 #include "opto/rootnode.hpp"
34 #include "opto/subnode.hpp"
35 #include "opto/type.hpp"
36 #include "castnode.hpp"
37 #include "utilities/checkedCast.hpp"
38
39 //=============================================================================
40 // If input is already higher or equal to cast type, then this is an identity.
41 Node* ConstraintCastNode::Identity(PhaseGVN* phase) {
42 if (_dependency == UnconditionalDependency) {
43 return this;
44 }
45 Node* dom = dominating_cast(phase, phase);
46 if (dom != nullptr) {
47 return dom;
48 }
49 return higher_equal_types(phase, in(1)) ? in(1) : this;
50 }
51
52 //------------------------------Value------------------------------------------
53 // Take 'join' of input and cast-up type
54 const Type* ConstraintCastNode::Value(PhaseGVN* phase) const {
55 if (in(0) && phase->type(in(0)) == Type::TOP) return Type::TOP;
56
57 const Type* in_type = phase->type(in(1));
58 const Type* ft = in_type->filter_speculative(_type);
59
60 // Check if both _type and in_type had a speculative type, but for the just
61 // computed ft the speculative type was dropped.
62 if (ft->speculative() == nullptr &&
63 _type->speculative() != nullptr &&
64 in_type->speculative() != nullptr) {
65 // Speculative type may have disagreed between cast and input, and was
66 // dropped in filtering. Recompute so that ft can take speculative type
67 // of in_type. If we did not do it now, a subsequent ::Value call would
68 // do it, and violate idempotence of ::Value.
69 ft = in_type->filter_speculative(ft);
70 }
71
72 #ifdef ASSERT
73 // Previous versions of this function had some special case logic,
74 // which is no longer necessary. Make sure of the required effects.
75 switch (Opcode()) {
76 case Op_CastII:
77 {
78 if (in_type == Type::TOP) {
79 assert(ft == Type::TOP, "special case #1");
80 }
81 const Type* rt = in_type->join_speculative(_type);
82 if (rt->empty()) {
83 assert(ft == Type::TOP, "special case #2");
84 }
85 break;
86 }
87 case Op_CastPP:
88 if (in_type == TypePtr::NULL_PTR &&
89 _type->isa_ptr() && _type->is_ptr()->_ptr == TypePtr::NotNull) {
90 assert(ft == Type::TOP, "special case #3");
91 break;
92 }
93 }
94 #endif //ASSERT
95
96 return ft;
97 }
98
99 //------------------------------Ideal------------------------------------------
100 // Return a node which is more "ideal" than the current node. Strip out
101 // control copies
102 Node *ConstraintCastNode::Ideal(PhaseGVN *phase, bool can_reshape) {
103 if (in(0) && remove_dead_region(phase, can_reshape)) {
104 return this;
105 }
106
107 // Push cast through InlineTypeNode
108 InlineTypeNode* vt = in(1)->isa_InlineType();
109 if (vt != nullptr && phase->type(vt)->filter_speculative(_type) != Type::TOP) {
110 Node* cast = clone();
111 cast->set_req(1, vt->get_oop());
112 vt = vt->clone()->as_InlineType();
113 if (!_type->maybe_null()) {
114 vt->as_InlineType()->set_is_init(*phase);
115 }
116 vt->set_oop(*phase, phase->transform(cast));
117 return vt;
118 }
119
120 return nullptr;
121 }
122
123 uint ConstraintCastNode::hash() const {
124 return TypeNode::hash() + (int)_dependency + (_extra_types != nullptr ? _extra_types->hash() : 0);
125 }
126
127 bool ConstraintCastNode::cmp(const Node &n) const {
128 if (!TypeNode::cmp(n)) {
129 return false;
130 }
131 ConstraintCastNode& cast = (ConstraintCastNode&) n;
132 if (cast._dependency != _dependency) {
133 return false;
134 }
135 if (_extra_types == nullptr || cast._extra_types == nullptr) {
136 return _extra_types == cast._extra_types;
137 }
138 return _extra_types->eq(cast._extra_types);
139 }
140
141 uint ConstraintCastNode::size_of() const {
142 return sizeof(*this);
143 }
144
145 Node* ConstraintCastNode::make_cast_for_basic_type(Node* c, Node* n, const Type* t, DependencyType dependency, BasicType bt) {
146 switch(bt) {
147 case T_INT:
148 return new CastIINode(c, n, t, dependency);
149 case T_LONG:
150 return new CastLLNode(c, n, t, dependency);
151 default:
152 fatal("Bad basic type %s", type2name(bt));
153 }
154 return nullptr;
155 }
156
157 TypeNode* ConstraintCastNode::dominating_cast(PhaseGVN* gvn, PhaseTransform* pt) const {
158 if (_dependency == UnconditionalDependency) {
159 return nullptr;
160 }
161 Node* val = in(1);
162 Node* ctl = in(0);
163 int opc = Opcode();
164 if (ctl == nullptr) {
165 return nullptr;
166 }
167 // Range check CastIIs may all end up under a single range check and
168 // in that case only the narrower CastII would be kept by the code
169 // below which would be incorrect.
170 if (is_CastII() && as_CastII()->has_range_check()) {
171 return nullptr;
172 }
173 if (type()->isa_rawptr() && (gvn->type_or_null(val) == nullptr || gvn->type(val)->isa_oopptr())) {
174 return nullptr;
175 }
176 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
177 Node* u = val->fast_out(i);
178 if (u != this &&
179 u->outcnt() > 0 &&
180 u->Opcode() == opc &&
181 u->in(0) != nullptr &&
182 higher_equal_types(gvn, u)) {
183 if (pt->is_dominator(u->in(0), ctl)) {
184 return u->as_Type();
185 }
186 if (is_CheckCastPP() && u->in(1)->is_Proj() && u->in(1)->in(0)->is_Allocate() &&
187 u->in(0)->is_Proj() && u->in(0)->in(0)->is_Initialize() &&
188 u->in(1)->in(0)->as_Allocate()->initialization() == u->in(0)->in(0)) {
189 // CheckCastPP following an allocation always dominates all
190 // use of the allocation result
191 return u->as_Type();
192 }
193 }
194 }
195 return nullptr;
196 }
197
198 bool ConstraintCastNode::higher_equal_types(PhaseGVN* phase, const Node* other) const {
199 const Type* t = phase->type(other);
200 if (!t->higher_equal_speculative(type())) {
201 return false;
202 }
203 if (_extra_types != nullptr) {
204 for (uint i = 0; i < _extra_types->cnt(); ++i) {
205 if (!t->higher_equal_speculative(_extra_types->field_at(i))) {
206 return false;
207 }
208 }
209 }
210 return true;
211 }
212
213 #ifndef PRODUCT
214 void ConstraintCastNode::dump_spec(outputStream *st) const {
215 TypeNode::dump_spec(st);
216 if (_extra_types != nullptr) {
217 st->print(" extra types: ");
218 _extra_types->dump_on(st);
219 }
220 if (_dependency != RegularDependency) {
221 st->print(" %s dependency", _dependency == StrongDependency ? "strong" : "unconditional");
222 }
223 }
224 #endif
225
226 const Type* CastIINode::Value(PhaseGVN* phase) const {
227 const Type *res = ConstraintCastNode::Value(phase);
228 if (res == Type::TOP) {
229 return Type::TOP;
230 }
231 assert(res->isa_int(), "res must be int");
232
233 // Similar to ConvI2LNode::Value() for the same reasons
234 // see if we can remove type assertion after loop opts
235 res = widen_type(phase, res, T_INT);
236
237 return res;
238 }
239
240 Node* ConstraintCastNode::find_or_make_integer_cast(PhaseIterGVN* igvn, Node* parent, const TypeInteger* type) const {
241 Node* n = clone();
242 n->set_req(1, parent);
243 n->as_ConstraintCast()->set_type(type);
244 Node* existing = igvn->hash_find_insert(n);
245 if (existing != nullptr) {
246 n->destruct(igvn);
247 return existing;
248 }
249 return igvn->register_new_node_with_optimizer(n);
250 }
251
252 Node *CastIINode::Ideal(PhaseGVN *phase, bool can_reshape) {
253 Node* progress = ConstraintCastNode::Ideal(phase, can_reshape);
254 if (progress != nullptr) {
255 return progress;
256 }
257 if (can_reshape && !phase->C->post_loop_opts_phase()) {
258 // makes sure we run ::Value to potentially remove type assertion after loop opts
259 phase->C->record_for_post_loop_opts_igvn(this);
260 }
261 if (!_range_check_dependency || phase->C->post_loop_opts_phase()) {
262 return optimize_integer_cast(phase, T_INT);
263 }
264 phase->C->record_for_post_loop_opts_igvn(this);
265 return nullptr;
266 }
267
268 Node* CastIINode::Identity(PhaseGVN* phase) {
269 Node* progress = ConstraintCastNode::Identity(phase);
270 if (progress != this) {
271 return progress;
272 }
273 return this;
274 }
275
276 bool CastIINode::cmp(const Node &n) const {
277 return ConstraintCastNode::cmp(n) && ((CastIINode&)n)._range_check_dependency == _range_check_dependency;
278 }
279
280 uint CastIINode::size_of() const {
281 return sizeof(*this);
282 }
283
284 #ifndef PRODUCT
285 void CastIINode::dump_spec(outputStream* st) const {
286 ConstraintCastNode::dump_spec(st);
287 if (_range_check_dependency) {
288 st->print(" range check dependency");
289 }
290 }
291 #endif
292
293 CastIINode* CastIINode::pin_array_access_node() const {
294 assert(_dependency == RegularDependency, "already pinned");
295 if (has_range_check()) {
296 return new CastIINode(in(0), in(1), bottom_type(), StrongDependency, has_range_check());
297 }
298 return nullptr;
299 }
300
301 void CastIINode::remove_range_check_cast(Compile* C) {
302 if (has_range_check()) {
303 // Range check CastII nodes feed into an address computation subgraph. Remove them to let that subgraph float freely.
304 // For memory access or integer divisions nodes that depend on the cast, record the dependency on the cast's control
305 // as a precedence edge, so they can't float above the cast in case that cast's narrowed type helped eliminate a
306 // range check or a null divisor check.
307 assert(in(0) != nullptr, "All RangeCheck CastII must have a control dependency");
308 ResourceMark rm;
309 Unique_Node_List wq;
310 wq.push(this);
311 for (uint next = 0; next < wq.size(); ++next) {
312 Node* m = wq.at(next);
313 for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
314 Node* use = m->fast_out(i);
315 if (use->is_Mem() || use->is_div_or_mod(T_INT) || use->is_div_or_mod(T_LONG)) {
316 use->ensure_control_or_add_prec(in(0));
317 } else if (!use->is_CFG() && !use->is_Phi()) {
318 wq.push(use);
319 }
320 }
321 }
322 subsume_by(in(1), C);
323 if (outcnt() == 0) {
324 disconnect_inputs(C);
325 }
326 }
327 }
328
329
330 const Type* CastLLNode::Value(PhaseGVN* phase) const {
331 const Type* res = ConstraintCastNode::Value(phase);
332 if (res == Type::TOP) {
333 return Type::TOP;
334 }
335 assert(res->isa_long(), "res must be long");
336
337 return widen_type(phase, res, T_LONG);
338 }
339
340 Node* CastLLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
341 Node* progress = ConstraintCastNode::Ideal(phase, can_reshape);
342 if (progress != nullptr) {
343 return progress;
344 }
345 if (!phase->C->post_loop_opts_phase()) {
346 // makes sure we run ::Value to potentially remove type assertion after loop opts
347 phase->C->record_for_post_loop_opts_igvn(this);
348 }
349 // transform (CastLL (ConvI2L ..)) into (ConvI2L (CastII ..)) if the type of the CastLL is narrower than the type of
350 // the ConvI2L.
351 Node* in1 = in(1);
352 if (in1 != nullptr && in1->Opcode() == Op_ConvI2L) {
353 const Type* t = Value(phase);
354 const Type* t_in = phase->type(in1);
355 if (t != Type::TOP && t_in != Type::TOP) {
356 const TypeLong* tl = t->is_long();
357 const TypeLong* t_in_l = t_in->is_long();
358 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");
359 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");
360 if (tl != t_in_l) {
361 const TypeInt* ti = TypeInt::make(checked_cast<jint>(tl->_lo), checked_cast<jint>(tl->_hi), tl->_widen);
362 Node* castii = phase->transform(new CastIINode(in(0), in1->in(1), ti));
363 Node* convi2l = in1->clone();
364 convi2l->set_req(1, castii);
365 return convi2l;
366 }
367 }
368 }
369 return optimize_integer_cast(phase, T_LONG);
370 }
371
372 //=============================================================================
373 //------------------------------Identity---------------------------------------
374 // If input is already higher or equal to cast type, then this is an identity.
375 Node* CheckCastPPNode::Identity(PhaseGVN* phase) {
376 if (in(1)->is_InlineType() && _type->isa_instptr() && phase->type(in(1))->inline_klass()->is_subtype_of(_type->is_instptr()->instance_klass())) {
377 return in(1);
378 }
379 return ConstraintCastNode::Identity(phase);
380 }
381
382 //------------------------------Value------------------------------------------
383 // Take 'join' of input and cast-up type, unless working with an Interface
384 const Type* CheckCastPPNode::Value(PhaseGVN* phase) const {
385 if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP;
386
387 const Type *inn = phase->type(in(1));
388 if( inn == Type::TOP ) return Type::TOP; // No information yet
389
390 if (inn->isa_oopptr() && _type->isa_oopptr()) {
391 return ConstraintCastNode::Value(phase);
392 }
393
394 const TypePtr *in_type = inn->isa_ptr();
395 const TypePtr *my_type = _type->isa_ptr();
396 const Type *result = _type;
397 if (in_type != nullptr && my_type != nullptr) {
398 // TODO 8302672
399 if (!StressReflectiveCode && my_type->isa_aryptr() && in_type->isa_aryptr()) {
400 // Propagate array properties (not flat/null-free)
401 // Don't do this when StressReflectiveCode is enabled because it might lead to
402 // a dying data path while the corresponding flat/null-free check is not folded.
403 my_type = my_type->is_aryptr()->update_properties(in_type->is_aryptr());
404 if (my_type == nullptr) {
405 return Type::TOP; // Inconsistent properties
406 }
407 }
408 TypePtr::PTR in_ptr = in_type->ptr();
409 if (in_ptr == TypePtr::Null) {
410 result = in_type;
411 } else if (in_ptr != TypePtr::Constant) {
412 result = my_type->cast_to_ptr_type(my_type->join_ptr(in_ptr));
413 }
414 }
415
416 return result;
417 }
418
419 //=============================================================================
420 //------------------------------Value------------------------------------------
421 const Type* CastX2PNode::Value(PhaseGVN* phase) const {
422 const Type* t = phase->type(in(1));
423 if (t == Type::TOP) return Type::TOP;
424 if (t->base() == Type_X && t->singleton()) {
425 uintptr_t bits = (uintptr_t) t->is_intptr_t()->get_con();
426 if (bits == 0) return TypePtr::NULL_PTR;
427 return TypeRawPtr::make((address) bits);
428 }
429 return CastX2PNode::bottom_type();
430 }
431
432 //------------------------------Idealize---------------------------------------
433 static inline bool fits_in_int(const Type* t, bool but_not_min_int = false) {
434 if (t == Type::TOP) return false;
435 const TypeX* tl = t->is_intptr_t();
436 jint lo = min_jint;
437 jint hi = max_jint;
438 if (but_not_min_int) ++lo; // caller wants to negate the value w/o overflow
439 return (tl->_lo >= lo) && (tl->_hi <= hi);
440 }
441
442 static inline Node* addP_of_X2P(PhaseGVN *phase,
443 Node* base,
444 Node* dispX,
445 bool negate = false) {
446 if (negate) {
447 dispX = phase->transform(new SubXNode(phase->MakeConX(0), dispX));
448 }
449 return new AddPNode(phase->C->top(),
450 phase->transform(new CastX2PNode(base)),
451 dispX);
452 }
453
454 Node *CastX2PNode::Ideal(PhaseGVN *phase, bool can_reshape) {
455 // convert CastX2P(AddX(x, y)) to AddP(CastX2P(x), y) if y fits in an int
456 int op = in(1)->Opcode();
457 Node* x;
458 Node* y;
459 switch (op) {
460 case Op_SubX:
461 x = in(1)->in(1);
462 // Avoid ideal transformations ping-pong between this and AddP for raw pointers.
463 if (phase->find_intptr_t_con(x, -1) == 0)
464 break;
465 y = in(1)->in(2);
466 if (fits_in_int(phase->type(y), true)) {
467 return addP_of_X2P(phase, x, y, true);
468 }
469 break;
470 case Op_AddX:
471 x = in(1)->in(1);
472 y = in(1)->in(2);
473 if (fits_in_int(phase->type(y))) {
474 return addP_of_X2P(phase, x, y);
475 }
476 if (fits_in_int(phase->type(x))) {
477 return addP_of_X2P(phase, y, x);
478 }
479 break;
480 }
481 return nullptr;
482 }
483
484 //------------------------------Identity---------------------------------------
485 Node* CastX2PNode::Identity(PhaseGVN* phase) {
486 if (in(1)->Opcode() == Op_CastP2X) return in(1)->in(1);
487 return this;
488 }
489
490 //=============================================================================
491 //------------------------------Value------------------------------------------
492 const Type* CastP2XNode::Value(PhaseGVN* phase) const {
493 const Type* t = phase->type(in(1));
494 if (t == Type::TOP) return Type::TOP;
495 if (t->base() == Type::RawPtr && t->singleton()) {
496 uintptr_t bits = (uintptr_t) t->is_rawptr()->get_con();
497 return TypeX::make(bits);
498 }
499
500 if (t->is_zero_type() || !t->maybe_null()) {
501 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
502 Node* u = fast_out(i);
503 if (u->Opcode() == Op_OrL) {
504 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
505 Node* cmp = u->fast_out(j);
506 if (cmp->Opcode() == Op_CmpL) {
507 // Give CmpL a chance to get optimized
508 phase->record_for_igvn(cmp);
509 }
510 }
511 }
512 }
513 }
514
515 return CastP2XNode::bottom_type();
516 }
517
518 Node *CastP2XNode::Ideal(PhaseGVN *phase, bool can_reshape) {
519 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : nullptr;
520 }
521
522 //------------------------------Identity---------------------------------------
523 Node* CastP2XNode::Identity(PhaseGVN* phase) {
524 if (in(1)->Opcode() == Op_CastX2P) return in(1)->in(1);
525 return this;
526 }
527
528 Node* ConstraintCastNode::make_cast_for_type(Node* c, Node* in, const Type* type, DependencyType dependency,
529 const TypeTuple* types) {
530 if (type->isa_int()) {
531 return new CastIINode(c, in, type, dependency, false, types);
532 } else if (type->isa_long()) {
533 return new CastLLNode(c, in, type, dependency, types);
534 } else if (type->isa_half_float()) {
535 return new CastHHNode(c, in, type, dependency, types);
536 } else if (type->isa_float()) {
537 return new CastFFNode(c, in, type, dependency, types);
538 } else if (type->isa_double()) {
539 return new CastDDNode(c, in, type, dependency, types);
540 } else if (type->isa_vect()) {
541 return new CastVVNode(c, in, type, dependency, types);
542 } else if (type->isa_ptr()) {
543 return new CastPPNode(c, in, type, dependency, types);
544 }
545 fatal("unreachable. Invalid cast type.");
546 return nullptr;
547 }
548
549 Node* ConstraintCastNode::optimize_integer_cast(PhaseGVN* phase, BasicType bt) {
550 PhaseIterGVN *igvn = phase->is_IterGVN();
551 const TypeInteger* this_type = this->type()->is_integer(bt);
552 Node* z = in(1);
553 const TypeInteger* rx = nullptr;
554 const TypeInteger* ry = nullptr;
555 // Similar to ConvI2LNode::Ideal() for the same reasons
556 if (Compile::push_thru_add(phase, z, this_type, rx, ry, bt, bt)) {
557 if (igvn == nullptr) {
558 // Postpone this optimization to iterative GVN, where we can handle deep
559 // AddI chains without an exponential number of recursive Ideal() calls.
560 phase->record_for_igvn(this);
561 return nullptr;
562 }
563 int op = z->Opcode();
564 Node* x = z->in(1);
565 Node* y = z->in(2);
566
567 Node* cx = find_or_make_integer_cast(igvn, x, rx);
568 Node* cy = find_or_make_integer_cast(igvn, y, ry);
569 if (op == Op_Add(bt)) {
570 return AddNode::make(cx, cy, bt);
571 } else {
572 assert(op == Op_Sub(bt), "");
573 return SubNode::make(cx, cy, bt);
574 }
575 return nullptr;
576 }
577 return nullptr;
578 }
579
580 const Type* ConstraintCastNode::widen_type(const PhaseGVN* phase, const Type* res, BasicType bt) const {
581 if (!phase->C->post_loop_opts_phase()) {
582 return res;
583 }
584 const TypeInteger* this_type = res->is_integer(bt);
585 const TypeInteger* in_type = phase->type(in(1))->isa_integer(bt);
586 if (in_type != nullptr &&
587 (in_type->lo_as_long() != this_type->lo_as_long() ||
588 in_type->hi_as_long() != this_type->hi_as_long())) {
589 jlong lo1 = this_type->lo_as_long();
590 jlong hi1 = this_type->hi_as_long();
591 int w1 = this_type->_widen;
592 if (lo1 >= 0) {
593 // Keep a range assertion of >=0.
594 lo1 = 0; hi1 = max_signed_integer(bt);
595 } else if (hi1 < 0) {
596 // Keep a range assertion of <0.
597 lo1 = min_signed_integer(bt); hi1 = -1;
598 } else {
599 lo1 = min_signed_integer(bt); hi1 = max_signed_integer(bt);
600 }
601 return TypeInteger::make(MAX2(in_type->lo_as_long(), lo1),
602 MIN2(in_type->hi_as_long(), hi1),
603 MAX2((int)in_type->_widen, w1), bt);
604 }
605 return res;
606 }