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 Node* cast = clone();
112 cast->set_req(1, vt->get_oop());
113 vt = vt->clone()->as_InlineType();
114 if (!_type->maybe_null()) {
115 vt->as_InlineType()->set_is_init(*phase);
116 }
117 vt->set_oop(*phase, phase->transform(cast));
118 return vt;
119 }
120
121 return nullptr;
122 }
123
124 uint ConstraintCastNode::hash() const {
125 return TypeNode::hash() + (int)_dependency + (_extra_types != nullptr ? _extra_types->hash() : 0);
126 }
127
128 bool ConstraintCastNode::cmp(const Node &n) const {
129 if (!TypeNode::cmp(n)) {
130 return false;
131 }
132 ConstraintCastNode& cast = (ConstraintCastNode&) n;
133 if (cast._dependency != _dependency) {
134 return false;
135 }
136 if (_extra_types == nullptr || cast._extra_types == nullptr) {
137 return _extra_types == cast._extra_types;
138 }
139 return _extra_types->eq(cast._extra_types);
140 }
141
142 uint ConstraintCastNode::size_of() const {
143 return sizeof(*this);
144 }
145
146 Node* ConstraintCastNode::make_cast_for_basic_type(Node* c, Node* n, const Type* t, DependencyType dependency, BasicType bt) {
147 switch(bt) {
148 case T_INT:
149 return new CastIINode(c, n, t, dependency);
150 case T_LONG:
151 return new CastLLNode(c, n, t, dependency);
152 default:
153 fatal("Bad basic type %s", type2name(bt));
154 }
155 return nullptr;
156 }
157
158 TypeNode* ConstraintCastNode::dominating_cast(PhaseGVN* gvn, PhaseTransform* pt) const {
159 if (_dependency == UnconditionalDependency) {
160 return nullptr;
161 }
162 Node* val = in(1);
163 Node* ctl = in(0);
164 int opc = Opcode();
165 if (ctl == nullptr) {
166 return nullptr;
167 }
168 // Range check CastIIs may all end up under a single range check and
169 // in that case only the narrower CastII would be kept by the code
170 // below which would be incorrect.
171 if (is_CastII() && as_CastII()->has_range_check()) {
172 return nullptr;
173 }
174 if (type()->isa_rawptr() && (gvn->type_or_null(val) == nullptr || gvn->type(val)->isa_oopptr())) {
175 return nullptr;
176 }
177 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
178 Node* u = val->fast_out(i);
179 if (u != this &&
180 u->outcnt() > 0 &&
181 u->Opcode() == opc &&
182 u->in(0) != nullptr &&
183 higher_equal_types(gvn, u)) {
184 if (pt->is_dominator(u->in(0), ctl)) {
185 return u->as_Type();
186 }
187 if (is_CheckCastPP() && u->in(1)->is_Proj() && u->in(1)->in(0)->is_Allocate() &&
188 u->in(0)->is_Proj() && u->in(0)->in(0)->is_Initialize() &&
189 u->in(1)->in(0)->as_Allocate()->initialization() == u->in(0)->in(0)) {
190 // CheckCastPP following an allocation always dominates all
191 // use of the allocation result
192 return u->as_Type();
193 }
194 }
195 }
196 return nullptr;
197 }
198
199 bool ConstraintCastNode::higher_equal_types(PhaseGVN* phase, const Node* other) const {
200 const Type* t = phase->type(other);
201 if (!t->higher_equal_speculative(type())) {
202 return false;
203 }
204 if (_extra_types != nullptr) {
205 for (uint i = 0; i < _extra_types->cnt(); ++i) {
206 if (!t->higher_equal_speculative(_extra_types->field_at(i))) {
207 return false;
208 }
209 }
210 }
211 return true;
212 }
213
214 #ifndef PRODUCT
215 void ConstraintCastNode::dump_spec(outputStream *st) const {
216 TypeNode::dump_spec(st);
217 if (_extra_types != nullptr) {
218 st->print(" extra types: ");
219 _extra_types->dump_on(st);
220 }
221 if (_dependency != RegularDependency) {
222 st->print(" %s dependency", _dependency == StrongDependency ? "strong" : "unconditional");
223 }
224 }
225 #endif
226
227 const Type* CastIINode::Value(PhaseGVN* phase) const {
228 const Type *res = ConstraintCastNode::Value(phase);
229 if (res == Type::TOP) {
230 return Type::TOP;
231 }
232 assert(res->isa_int(), "res must be int");
233
234 // Similar to ConvI2LNode::Value() for the same reasons
235 // see if we can remove type assertion after loop opts
236 // But here we have to pay extra attention:
237 // Do not narrow the type of range check dependent CastIINodes to
238 // avoid corruption of the graph if a CastII is replaced by TOP but
239 // the corresponding range check is not removed.
240 if (!_range_check_dependency) {
241 res = widen_type(phase, res, T_INT);
242 }
243
244 return res;
245 }
246
247 static Node* find_or_make_integer_cast(PhaseIterGVN* igvn, Node* parent, Node* control, const TypeInteger* type, ConstraintCastNode::DependencyType dependency, BasicType bt) {
248 Node* n = ConstraintCastNode::make_cast_for_basic_type(control, parent, type, dependency, bt);
249 Node* existing = igvn->hash_find_insert(n);
250 if (existing != nullptr) {
251 n->destruct(igvn);
252 return existing;
253 }
254 return igvn->register_new_node_with_optimizer(n);
255 }
256
257 Node *CastIINode::Ideal(PhaseGVN *phase, bool can_reshape) {
258 Node* progress = ConstraintCastNode::Ideal(phase, can_reshape);
259 if (progress != nullptr) {
260 return progress;
261 }
262 if (can_reshape && !_range_check_dependency && !phase->C->post_loop_opts_phase()) {
263 // makes sure we run ::Value to potentially remove type assertion after loop opts
264 phase->C->record_for_post_loop_opts_igvn(this);
265 }
266 if (!_range_check_dependency) {
267 return optimize_integer_cast(phase, T_INT);
268 }
269 return nullptr;
270 }
271
272 Node* CastIINode::Identity(PhaseGVN* phase) {
273 Node* progress = ConstraintCastNode::Identity(phase);
274 if (progress != this) {
275 return progress;
276 }
277 if (_range_check_dependency) {
278 if (phase->C->post_loop_opts_phase()) {
279 return this->in(1);
280 } else {
281 phase->C->record_for_post_loop_opts_igvn(this);
282 }
283 }
284 return this;
285 }
286
287 bool CastIINode::cmp(const Node &n) const {
288 return ConstraintCastNode::cmp(n) && ((CastIINode&)n)._range_check_dependency == _range_check_dependency;
289 }
290
291 uint CastIINode::size_of() const {
292 return sizeof(*this);
293 }
294
295 #ifndef PRODUCT
296 void CastIINode::dump_spec(outputStream* st) const {
297 ConstraintCastNode::dump_spec(st);
298 if (_range_check_dependency) {
299 st->print(" range check dependency");
300 }
301 }
302 #endif
303
304 CastIINode* CastIINode::pin_array_access_node() const {
305 assert(_dependency == RegularDependency, "already pinned");
306 if (has_range_check()) {
307 return new CastIINode(in(0), in(1), bottom_type(), StrongDependency, has_range_check());
308 }
309 return nullptr;
310 }
311
312
313 const Type* CastLLNode::Value(PhaseGVN* phase) const {
314 const Type* res = ConstraintCastNode::Value(phase);
315 if (res == Type::TOP) {
316 return Type::TOP;
317 }
318 assert(res->isa_long(), "res must be long");
319
320 return widen_type(phase, res, T_LONG);
321 }
322
323 Node* CastLLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
324 Node* progress = ConstraintCastNode::Ideal(phase, can_reshape);
325 if (progress != nullptr) {
326 return progress;
327 }
328 if (!phase->C->post_loop_opts_phase()) {
329 // makes sure we run ::Value to potentially remove type assertion after loop opts
330 phase->C->record_for_post_loop_opts_igvn(this);
331 }
332 // transform (CastLL (ConvI2L ..)) into (ConvI2L (CastII ..)) if the type of the CastLL is narrower than the type of
333 // the ConvI2L.
334 Node* in1 = in(1);
335 if (in1 != nullptr && in1->Opcode() == Op_ConvI2L) {
336 const Type* t = Value(phase);
337 const Type* t_in = phase->type(in1);
338 if (t != Type::TOP && t_in != Type::TOP) {
339 const TypeLong* tl = t->is_long();
340 const TypeLong* t_in_l = t_in->is_long();
341 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");
342 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");
343 if (tl != t_in_l) {
344 const TypeInt* ti = TypeInt::make(checked_cast<jint>(tl->_lo), checked_cast<jint>(tl->_hi), tl->_widen);
345 Node* castii = phase->transform(new CastIINode(in(0), in1->in(1), ti));
346 Node* convi2l = in1->clone();
347 convi2l->set_req(1, castii);
348 return convi2l;
349 }
350 }
351 }
352 return optimize_integer_cast(phase, T_LONG);
353 }
354
355 //=============================================================================
356 //------------------------------Identity---------------------------------------
357 // If input is already higher or equal to cast type, then this is an identity.
358 Node* CheckCastPPNode::Identity(PhaseGVN* phase) {
359 if (in(1)->is_InlineType() && _type->isa_instptr() && phase->type(in(1))->inline_klass()->is_subtype_of(_type->is_instptr()->instance_klass())) {
360 return in(1);
361 }
362 return ConstraintCastNode::Identity(phase);
363 }
364
365 //------------------------------Value------------------------------------------
366 // Take 'join' of input and cast-up type, unless working with an Interface
367 const Type* CheckCastPPNode::Value(PhaseGVN* phase) const {
368 if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP;
369
370 const Type *inn = phase->type(in(1));
371 if( inn == Type::TOP ) return Type::TOP; // No information yet
372
373 if (inn->isa_oopptr() && _type->isa_oopptr()) {
374 return ConstraintCastNode::Value(phase);
375 }
376
377 const TypePtr *in_type = inn->isa_ptr();
378 const TypePtr *my_type = _type->isa_ptr();
379 const Type *result = _type;
380 if (in_type != nullptr && my_type != nullptr) {
381 // TODO 8302672
382 if (!StressReflectiveCode && my_type->isa_aryptr() && in_type->isa_aryptr()) {
383 // Propagate array properties (not flat/null-free)
384 // Don't do this when StressReflectiveCode is enabled because it might lead to
385 // a dying data path while the corresponding flat/null-free check is not folded.
386 my_type = my_type->is_aryptr()->update_properties(in_type->is_aryptr());
387 if (my_type == nullptr) {
388 return Type::TOP; // Inconsistent properties
389 }
390 }
391 TypePtr::PTR in_ptr = in_type->ptr();
392 if (in_ptr == TypePtr::Null) {
393 result = in_type;
394 } else if (in_ptr != TypePtr::Constant) {
395 result = my_type->cast_to_ptr_type(my_type->join_ptr(in_ptr));
396 }
397 }
398
399 return result;
400 }
401
402 //=============================================================================
403 //------------------------------Value------------------------------------------
404 const Type* CastX2PNode::Value(PhaseGVN* phase) const {
405 const Type* t = phase->type(in(1));
406 if (t == Type::TOP) return Type::TOP;
407 if (t->base() == Type_X && t->singleton()) {
408 uintptr_t bits = (uintptr_t) t->is_intptr_t()->get_con();
409 if (bits == 0) return TypePtr::NULL_PTR;
410 return TypeRawPtr::make((address) bits);
411 }
412 return CastX2PNode::bottom_type();
413 }
414
415 //------------------------------Idealize---------------------------------------
416 static inline bool fits_in_int(const Type* t, bool but_not_min_int = false) {
417 if (t == Type::TOP) return false;
418 const TypeX* tl = t->is_intptr_t();
419 jint lo = min_jint;
420 jint hi = max_jint;
421 if (but_not_min_int) ++lo; // caller wants to negate the value w/o overflow
422 return (tl->_lo >= lo) && (tl->_hi <= hi);
423 }
424
425 static inline Node* addP_of_X2P(PhaseGVN *phase,
426 Node* base,
427 Node* dispX,
428 bool negate = false) {
429 if (negate) {
430 dispX = phase->transform(new SubXNode(phase->MakeConX(0), dispX));
431 }
432 return new AddPNode(phase->C->top(),
433 phase->transform(new CastX2PNode(base)),
434 dispX);
435 }
436
437 Node *CastX2PNode::Ideal(PhaseGVN *phase, bool can_reshape) {
438 // convert CastX2P(AddX(x, y)) to AddP(CastX2P(x), y) if y fits in an int
439 int op = in(1)->Opcode();
440 Node* x;
441 Node* y;
442 switch (op) {
443 case Op_SubX:
444 x = in(1)->in(1);
445 // Avoid ideal transformations ping-pong between this and AddP for raw pointers.
446 if (phase->find_intptr_t_con(x, -1) == 0)
447 break;
448 y = in(1)->in(2);
449 if (fits_in_int(phase->type(y), true)) {
450 return addP_of_X2P(phase, x, y, true);
451 }
452 break;
453 case Op_AddX:
454 x = in(1)->in(1);
455 y = in(1)->in(2);
456 if (fits_in_int(phase->type(y))) {
457 return addP_of_X2P(phase, x, y);
458 }
459 if (fits_in_int(phase->type(x))) {
460 return addP_of_X2P(phase, y, x);
461 }
462 break;
463 }
464 return nullptr;
465 }
466
467 //------------------------------Identity---------------------------------------
468 Node* CastX2PNode::Identity(PhaseGVN* phase) {
469 if (in(1)->Opcode() == Op_CastP2X) return in(1)->in(1);
470 return this;
471 }
472
473 //=============================================================================
474 //------------------------------Value------------------------------------------
475 const Type* CastP2XNode::Value(PhaseGVN* phase) const {
476 const Type* t = phase->type(in(1));
477 if (t == Type::TOP) return Type::TOP;
478 if (t->base() == Type::RawPtr && t->singleton()) {
479 uintptr_t bits = (uintptr_t) t->is_rawptr()->get_con();
480 return TypeX::make(bits);
481 }
482
483 if (t->is_zero_type() || !t->maybe_null()) {
484 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
485 Node* u = fast_out(i);
486 if (u->Opcode() == Op_OrL) {
487 for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
488 Node* cmp = u->fast_out(j);
489 if (cmp->Opcode() == Op_CmpL) {
490 // Give CmpL a chance to get optimized
491 phase->record_for_igvn(cmp);
492 }
493 }
494 }
495 }
496 }
497
498 return CastP2XNode::bottom_type();
499 }
500
501 Node *CastP2XNode::Ideal(PhaseGVN *phase, bool can_reshape) {
502 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : nullptr;
503 }
504
505 //------------------------------Identity---------------------------------------
506 Node* CastP2XNode::Identity(PhaseGVN* phase) {
507 if (in(1)->Opcode() == Op_CastX2P) return in(1)->in(1);
508 return this;
509 }
510
511 Node* ConstraintCastNode::make_cast_for_type(Node* c, Node* in, const Type* type, DependencyType dependency,
512 const TypeTuple* types) {
513 if (type->isa_int()) {
514 return new CastIINode(c, in, type, dependency, false, types);
515 } else if (type->isa_long()) {
516 return new CastLLNode(c, in, type, dependency, types);
517 } else if (type->isa_float()) {
518 return new CastFFNode(c, in, type, dependency, types);
519 } else if (type->isa_double()) {
520 return new CastDDNode(c, in, type, dependency, types);
521 } else if (type->isa_vect()) {
522 return new CastVVNode(c, in, type, dependency, types);
523 } else if (type->isa_ptr()) {
524 return new CastPPNode(c, in, type, dependency, types);
525 }
526 fatal("unreachable. Invalid cast type.");
527 return nullptr;
528 }
529
530 Node* ConstraintCastNode::optimize_integer_cast(PhaseGVN* phase, BasicType bt) {
531 PhaseIterGVN *igvn = phase->is_IterGVN();
532 const TypeInteger* this_type = this->type()->is_integer(bt);
533 Node* z = in(1);
534 const TypeInteger* rx = nullptr;
535 const TypeInteger* ry = nullptr;
536 // Similar to ConvI2LNode::Ideal() for the same reasons
537 if (Compile::push_thru_add(phase, z, this_type, rx, ry, bt, bt)) {
538 if (igvn == nullptr) {
539 // Postpone this optimization to iterative GVN, where we can handle deep
540 // AddI chains without an exponential number of recursive Ideal() calls.
541 phase->record_for_igvn(this);
542 return nullptr;
543 }
544 int op = z->Opcode();
545 Node* x = z->in(1);
546 Node* y = z->in(2);
547
548 Node* cx = find_or_make_integer_cast(igvn, x, in(0), rx, _dependency, bt);
549 Node* cy = find_or_make_integer_cast(igvn, y, in(0), ry, _dependency, bt);
550 if (op == Op_Add(bt)) {
551 return AddNode::make(cx, cy, bt);
552 } else {
553 assert(op == Op_Sub(bt), "");
554 return SubNode::make(cx, cy, bt);
555 }
556 return nullptr;
557 }
558 return nullptr;
559 }
560
561 const Type* ConstraintCastNode::widen_type(const PhaseGVN* phase, const Type* res, BasicType bt) const {
562 if (!phase->C->post_loop_opts_phase()) {
563 return res;
564 }
565 const TypeInteger* this_type = res->is_integer(bt);
566 const TypeInteger* in_type = phase->type(in(1))->isa_integer(bt);
567 if (in_type != nullptr &&
568 (in_type->lo_as_long() != this_type->lo_as_long() ||
569 in_type->hi_as_long() != this_type->hi_as_long())) {
570 jlong lo1 = this_type->lo_as_long();
571 jlong hi1 = this_type->hi_as_long();
572 int w1 = this_type->_widen;
573 if (lo1 >= 0) {
574 // Keep a range assertion of >=0.
575 lo1 = 0; hi1 = max_signed_integer(bt);
576 } else if (hi1 < 0) {
577 // Keep a range assertion of <0.
578 lo1 = min_signed_integer(bt); hi1 = -1;
579 } else {
580 lo1 = min_signed_integer(bt); hi1 = max_signed_integer(bt);
581 }
582 return TypeInteger::make(MAX2(in_type->lo_as_long(), lo1),
583 MIN2(in_type->hi_as_long(), hi1),
584 MAX2((int)in_type->_widen, w1), bt);
585 }
586 return res;
587 }