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 "castnode.hpp" 26 #include "opto/addnode.hpp" 27 #include "opto/callnode.hpp" 28 #include "opto/castnode.hpp" 29 #include "opto/cfgnode.hpp" 30 #include "opto/connode.hpp" 31 #include "opto/loopnode.hpp" 32 #include "opto/matcher.hpp" 33 #include "opto/phaseX.hpp" 34 #include "opto/subnode.hpp" 35 #include "opto/type.hpp" 36 #include "utilities/checkedCast.hpp" 37 38 //============================================================================= 39 // If input is already higher or equal to cast type, then this is an identity. 40 Node* ConstraintCastNode::Identity(PhaseGVN* phase) { 41 if (_dependency == UnconditionalDependency) { 42 return this; 43 } 44 Node* dom = dominating_cast(phase, phase); 45 if (dom != nullptr) { 46 return dom; 47 } 48 return higher_equal_types(phase, in(1)) ? in(1) : this; 49 } 50 51 //------------------------------Value------------------------------------------ 52 // Take 'join' of input and cast-up type 53 const Type* ConstraintCastNode::Value(PhaseGVN* phase) const { 54 if (in(0) && phase->type(in(0)) == Type::TOP) return Type::TOP; 55 56 const Type* in_type = phase->type(in(1)); 57 const Type* ft = in_type->filter_speculative(_type); 58 59 // Check if both _type and in_type had a speculative type, but for the just 60 // computed ft the speculative type was dropped. 61 if (ft->speculative() == nullptr && 62 _type->speculative() != nullptr && 63 in_type->speculative() != nullptr) { 64 // Speculative type may have disagreed between cast and input, and was 65 // dropped in filtering. Recompute so that ft can take speculative type 66 // of in_type. If we did not do it now, a subsequent ::Value call would 67 // do it, and violate idempotence of ::Value. 68 ft = in_type->filter_speculative(ft); 69 } 70 71 #ifdef ASSERT 72 // Previous versions of this function had some special case logic, 73 // which is no longer necessary. Make sure of the required effects. 74 switch (Opcode()) { 75 case Op_CastII: 76 { 77 if (in_type == Type::TOP) { 78 assert(ft == Type::TOP, "special case #1"); 79 } 80 const Type* rt = in_type->join_speculative(_type); 81 if (rt->empty()) { 82 assert(ft == Type::TOP, "special case #2"); 83 } 84 break; 85 } 86 case Op_CastPP: 87 if (in_type == TypePtr::NULL_PTR && 88 _type->isa_ptr() && _type->is_ptr()->_ptr == TypePtr::NotNull) { 89 assert(ft == Type::TOP, "special case #3"); 90 break; 91 } 92 } 93 #endif //ASSERT 94 95 return ft; 96 } 97 98 //------------------------------Ideal------------------------------------------ 99 // Return a node which is more "ideal" than the current node. Strip out 100 // control copies 101 Node* ConstraintCastNode::Ideal(PhaseGVN* phase, bool can_reshape) { 102 if (in(0) != nullptr && remove_dead_region(phase, can_reshape)) { 103 return this; 104 } 105 if (in(1) != nullptr && phase->type(in(1)) != Type::TOP) { 106 return TypeNode::Ideal(phase, can_reshape); 107 } 108 return nullptr; 109 } 110 111 uint ConstraintCastNode::hash() const { 112 return TypeNode::hash() + (int)_dependency + (_extra_types != nullptr ? _extra_types->hash() : 0); 113 } 114 115 bool ConstraintCastNode::cmp(const Node &n) const { 116 if (!TypeNode::cmp(n)) { 117 return false; 118 } 119 ConstraintCastNode& cast = (ConstraintCastNode&) n; 120 if (cast._dependency != _dependency) { 121 return false; 122 } 123 if (_extra_types == nullptr || cast._extra_types == nullptr) { 124 return _extra_types == cast._extra_types; 125 } 126 return _extra_types->eq(cast._extra_types); 127 } 128 129 uint ConstraintCastNode::size_of() const { 130 return sizeof(*this); 131 } 132 133 Node* ConstraintCastNode::make_cast_for_basic_type(Node* c, Node* n, const Type* t, DependencyType dependency, BasicType bt) { 134 switch(bt) { 135 case T_INT: 136 return new CastIINode(c, n, t, dependency); 137 case T_LONG: 138 return new CastLLNode(c, n, t, dependency); 139 default: 140 fatal("Bad basic type %s", type2name(bt)); 141 } 142 return nullptr; 143 } 144 145 TypeNode* ConstraintCastNode::dominating_cast(PhaseGVN* gvn, PhaseTransform* pt) const { 146 if (_dependency == UnconditionalDependency) { 147 return nullptr; 148 } 149 Node* val = in(1); 150 Node* ctl = in(0); 151 int opc = Opcode(); 152 if (ctl == nullptr) { 153 return nullptr; 154 } 155 // Range check CastIIs may all end up under a single range check and 156 // in that case only the narrower CastII would be kept by the code 157 // below which would be incorrect. 158 if (is_CastII() && as_CastII()->has_range_check()) { 159 return nullptr; 160 } 161 if (type()->isa_rawptr() && (gvn->type_or_null(val) == nullptr || gvn->type(val)->isa_oopptr())) { 162 return nullptr; 163 } 164 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) { 165 Node* u = val->fast_out(i); 166 if (u != this && 167 u->outcnt() > 0 && 168 u->Opcode() == opc && 169 u->in(0) != nullptr && 170 higher_equal_types(gvn, u)) { 171 if (pt->is_dominator(u->in(0), ctl)) { 172 return u->as_Type(); 173 } 174 if (is_CheckCastPP() && u->in(1)->is_Proj() && u->in(1)->in(0)->is_Allocate() && 175 u->in(0)->is_Proj() && u->in(0)->in(0)->is_Initialize() && 176 u->in(1)->in(0)->as_Allocate()->initialization() == u->in(0)->in(0)) { 177 // CheckCastPP following an allocation always dominates all 178 // use of the allocation result 179 return u->as_Type(); 180 } 181 } 182 } 183 return nullptr; 184 } 185 186 bool ConstraintCastNode::higher_equal_types(PhaseGVN* phase, const Node* other) const { 187 const Type* t = phase->type(other); 188 if (!t->higher_equal_speculative(type())) { 189 return false; 190 } 191 if (_extra_types != nullptr) { 192 for (uint i = 0; i < _extra_types->cnt(); ++i) { 193 if (!t->higher_equal_speculative(_extra_types->field_at(i))) { 194 return false; 195 } 196 } 197 } 198 return true; 199 } 200 201 #ifndef PRODUCT 202 void ConstraintCastNode::dump_spec(outputStream *st) const { 203 TypeNode::dump_spec(st); 204 if (_extra_types != nullptr) { 205 st->print(" extra types: "); 206 _extra_types->dump_on(st); 207 } 208 if (_dependency != RegularDependency) { 209 st->print(" %s dependency", _dependency == StrongDependency ? "strong" : "unconditional"); 210 } 211 } 212 #endif 213 214 const Type* CastIINode::Value(PhaseGVN* phase) const { 215 const Type *res = ConstraintCastNode::Value(phase); 216 if (res == Type::TOP) { 217 return Type::TOP; 218 } 219 assert(res->isa_int(), "res must be int"); 220 221 // Similar to ConvI2LNode::Value() for the same reasons 222 // see if we can remove type assertion after loop opts 223 res = widen_type(phase, res, T_INT); 224 225 return res; 226 } 227 228 Node* ConstraintCastNode::find_or_make_integer_cast(PhaseIterGVN* igvn, Node* parent, const TypeInteger* type) const { 229 Node* n = clone(); 230 n->set_req(1, parent); 231 n->as_ConstraintCast()->set_type(type); 232 Node* existing = igvn->hash_find_insert(n); 233 if (existing != nullptr) { 234 n->destruct(igvn); 235 return existing; 236 } 237 return igvn->register_new_node_with_optimizer(n); 238 } 239 240 Node *CastIINode::Ideal(PhaseGVN *phase, bool can_reshape) { 241 Node* progress = ConstraintCastNode::Ideal(phase, can_reshape); 242 if (progress != nullptr) { 243 return progress; 244 } 245 if (can_reshape && !phase->C->post_loop_opts_phase()) { 246 // makes sure we run ::Value to potentially remove type assertion after loop opts 247 phase->C->record_for_post_loop_opts_igvn(this); 248 } 249 if (!_range_check_dependency || phase->C->post_loop_opts_phase()) { 250 return optimize_integer_cast(phase, T_INT); 251 } 252 phase->C->record_for_post_loop_opts_igvn(this); 253 return nullptr; 254 } 255 256 Node* CastIINode::Identity(PhaseGVN* phase) { 257 Node* progress = ConstraintCastNode::Identity(phase); 258 if (progress != this) { 259 return progress; 260 } 261 return this; 262 } 263 264 bool CastIINode::cmp(const Node &n) const { 265 return ConstraintCastNode::cmp(n) && ((CastIINode&)n)._range_check_dependency == _range_check_dependency; 266 } 267 268 uint CastIINode::size_of() const { 269 return sizeof(*this); 270 } 271 272 #ifndef PRODUCT 273 void CastIINode::dump_spec(outputStream* st) const { 274 ConstraintCastNode::dump_spec(st); 275 if (_range_check_dependency) { 276 st->print(" range check dependency"); 277 } 278 } 279 #endif 280 281 CastIINode* CastIINode::pin_array_access_node() const { 282 assert(_dependency == RegularDependency, "already pinned"); 283 if (has_range_check()) { 284 return new CastIINode(in(0), in(1), bottom_type(), StrongDependency, has_range_check()); 285 } 286 return nullptr; 287 } 288 289 void CastIINode::remove_range_check_cast(Compile* C) { 290 if (has_range_check()) { 291 // Range check CastII nodes feed into an address computation subgraph. Remove them to let that subgraph float freely. 292 // For memory access or integer divisions nodes that depend on the cast, record the dependency on the cast's control 293 // as a precedence edge, so they can't float above the cast in case that cast's narrowed type helped eliminate a 294 // range check or a null divisor check. 295 assert(in(0) != nullptr, "All RangeCheck CastII must have a control dependency"); 296 ResourceMark rm; 297 Unique_Node_List wq; 298 wq.push(this); 299 for (uint next = 0; next < wq.size(); ++next) { 300 Node* m = wq.at(next); 301 for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) { 302 Node* use = m->fast_out(i); 303 if (use->is_Mem() || use->is_div_or_mod(T_INT) || use->is_div_or_mod(T_LONG)) { 304 use->ensure_control_or_add_prec(in(0)); 305 } else if (!use->is_CFG() && !use->is_Phi()) { 306 wq.push(use); 307 } 308 } 309 } 310 subsume_by(in(1), C); 311 if (outcnt() == 0) { 312 disconnect_inputs(C); 313 } 314 } 315 } 316 317 318 const Type* CastLLNode::Value(PhaseGVN* phase) const { 319 const Type* res = ConstraintCastNode::Value(phase); 320 if (res == Type::TOP) { 321 return Type::TOP; 322 } 323 assert(res->isa_long(), "res must be long"); 324 325 return widen_type(phase, res, T_LONG); 326 } 327 328 bool CastLLNode::is_inner_loop_backedge(ProjNode* proj) { 329 if (proj != nullptr) { 330 Node* ctrl_use = proj->unique_ctrl_out_or_null(); 331 if (ctrl_use != nullptr && ctrl_use->Opcode() == Op_Loop && 332 ctrl_use->in(2) == proj && 333 ctrl_use->as_Loop()->is_loop_nest_inner_loop()) { 334 return true; 335 } 336 } 337 return false; 338 } 339 340 bool CastLLNode::cmp_used_at_inner_loop_exit_test(CmpNode* cmp) { 341 for (DUIterator_Fast imax, i = cmp->fast_outs(imax); i < imax; i++) { 342 Node* bol = cmp->fast_out(i); 343 if (bol->Opcode() == Op_Bool) { 344 for (DUIterator_Fast jmax, j = bol->fast_outs(jmax); j < jmax; j++) { 345 Node* iff = bol->fast_out(j); 346 if (iff->Opcode() == Op_If) { 347 ProjNode* true_proj = iff->as_If()->proj_out_or_null(true); 348 ProjNode* false_proj = iff->as_If()->proj_out_or_null(false); 349 if (is_inner_loop_backedge(true_proj) || is_inner_loop_backedge(false_proj)) { 350 return true; 351 } 352 } 353 } 354 } 355 } 356 return false; 357 } 358 359 // Find if this is a cast node added by PhaseIdealLoop::create_loop_nest() to narrow the number of iterations of the 360 // inner loop 361 bool CastLLNode::used_at_inner_loop_exit_test() const { 362 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) { 363 Node* convl2i = fast_out(i); 364 if (convl2i->Opcode() == Op_ConvL2I) { 365 for (DUIterator_Fast jmax, j = convl2i->fast_outs(jmax); j < jmax; j++) { 366 Node* cmp_or_sub = convl2i->fast_out(j); 367 if (cmp_or_sub->Opcode() == Op_CmpI) { 368 if (cmp_used_at_inner_loop_exit_test(cmp_or_sub->as_Cmp())) { 369 // (Loop .. .. (IfProj (If (Bool (CmpI (ConvL2I (CastLL ))))))) 370 return true; 371 } 372 } else if (cmp_or_sub->Opcode() == Op_SubI && cmp_or_sub->in(1)->find_int_con(-1) == 0) { 373 for (DUIterator_Fast kmax, k = cmp_or_sub->fast_outs(kmax); k < kmax; k++) { 374 Node* cmp = cmp_or_sub->fast_out(k); 375 if (cmp->Opcode() == Op_CmpI) { 376 if (cmp_used_at_inner_loop_exit_test(cmp->as_Cmp())) { 377 // (Loop .. .. (IfProj (If (Bool (CmpI (SubI 0 (ConvL2I (CastLL )))))))) 378 return true; 379 } 380 } 381 } 382 } 383 } 384 } 385 } 386 return false; 387 } 388 389 Node* CastLLNode::Ideal(PhaseGVN* phase, bool can_reshape) { 390 Node* progress = ConstraintCastNode::Ideal(phase, can_reshape); 391 if (progress != nullptr) { 392 return progress; 393 } 394 if (!phase->C->post_loop_opts_phase()) { 395 // makes sure we run ::Value to potentially remove type assertion after loop opts 396 phase->C->record_for_post_loop_opts_igvn(this); 397 } 398 // transform (CastLL (ConvI2L ..)) into (ConvI2L (CastII ..)) if the type of the CastLL is narrower than the type of 399 // the ConvI2L. 400 Node* in1 = in(1); 401 if (in1 != nullptr && in1->Opcode() == Op_ConvI2L) { 402 const Type* t = Value(phase); 403 const Type* t_in = phase->type(in1); 404 if (t != Type::TOP && t_in != Type::TOP) { 405 const TypeLong* tl = t->is_long(); 406 const TypeLong* t_in_l = t_in->is_long(); 407 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"); 408 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"); 409 if (tl != t_in_l) { 410 const TypeInt* ti = TypeInt::make(checked_cast<jint>(tl->_lo), checked_cast<jint>(tl->_hi), tl->_widen); 411 Node* castii = phase->transform(new CastIINode(in(0), in1->in(1), ti)); 412 Node* convi2l = in1->clone(); 413 convi2l->set_req(1, castii); 414 return convi2l; 415 } 416 } 417 } 418 // If it's a cast created by PhaseIdealLoop::short_running_loop(), don't transform it until the counted loop is created 419 // in next loop opts pass 420 if (!can_reshape || !used_at_inner_loop_exit_test()) { 421 return optimize_integer_cast(phase, T_LONG); 422 } 423 return nullptr; 424 } 425 426 //------------------------------Value------------------------------------------ 427 // Take 'join' of input and cast-up type, unless working with an Interface 428 const Type* CheckCastPPNode::Value(PhaseGVN* phase) const { 429 if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP; 430 431 const Type *inn = phase->type(in(1)); 432 if( inn == Type::TOP ) return Type::TOP; // No information yet 433 434 if (inn->isa_oopptr() && _type->isa_oopptr()) { 435 return ConstraintCastNode::Value(phase); 436 } 437 438 const TypePtr *in_type = inn->isa_ptr(); 439 const TypePtr *my_type = _type->isa_ptr(); 440 const Type *result = _type; 441 if (in_type != nullptr && my_type != nullptr) { 442 TypePtr::PTR in_ptr = in_type->ptr(); 443 if (in_ptr == TypePtr::Null) { 444 result = in_type; 445 } else if (in_ptr != TypePtr::Constant) { 446 result = my_type->cast_to_ptr_type(my_type->join_ptr(in_ptr)); 447 } 448 } 449 450 return result; 451 } 452 453 //============================================================================= 454 //------------------------------Value------------------------------------------ 455 const Type* CastX2PNode::Value(PhaseGVN* phase) const { 456 const Type* t = phase->type(in(1)); 457 if (t == Type::TOP) return Type::TOP; 458 if (t->base() == Type_X && t->singleton()) { 459 uintptr_t bits = (uintptr_t) t->is_intptr_t()->get_con(); 460 if (bits == 0) return TypePtr::NULL_PTR; 461 return TypeRawPtr::make((address) bits); 462 } 463 return CastX2PNode::bottom_type(); 464 } 465 466 //------------------------------Idealize--------------------------------------- 467 static inline bool fits_in_int(const Type* t, bool but_not_min_int = false) { 468 if (t == Type::TOP) return false; 469 const TypeX* tl = t->is_intptr_t(); 470 jint lo = min_jint; 471 jint hi = max_jint; 472 if (but_not_min_int) ++lo; // caller wants to negate the value w/o overflow 473 return (tl->_lo >= lo) && (tl->_hi <= hi); 474 } 475 476 static inline Node* addP_of_X2P(PhaseGVN *phase, 477 Node* base, 478 Node* dispX, 479 bool negate = false) { 480 if (negate) { 481 dispX = phase->transform(new SubXNode(phase->MakeConX(0), dispX)); 482 } 483 return new AddPNode(phase->C->top(), 484 phase->transform(new CastX2PNode(base)), 485 dispX); 486 } 487 488 Node *CastX2PNode::Ideal(PhaseGVN *phase, bool can_reshape) { 489 // convert CastX2P(AddX(x, y)) to AddP(CastX2P(x), y) if y fits in an int 490 int op = in(1)->Opcode(); 491 Node* x; 492 Node* y; 493 switch (op) { 494 case Op_SubX: 495 x = in(1)->in(1); 496 // Avoid ideal transformations ping-pong between this and AddP for raw pointers. 497 if (phase->find_intptr_t_con(x, -1) == 0) 498 break; 499 y = in(1)->in(2); 500 if (fits_in_int(phase->type(y), true)) { 501 return addP_of_X2P(phase, x, y, true); 502 } 503 break; 504 case Op_AddX: 505 x = in(1)->in(1); 506 y = in(1)->in(2); 507 if (fits_in_int(phase->type(y))) { 508 return addP_of_X2P(phase, x, y); 509 } 510 if (fits_in_int(phase->type(x))) { 511 return addP_of_X2P(phase, y, x); 512 } 513 break; 514 } 515 return nullptr; 516 } 517 518 //------------------------------Identity--------------------------------------- 519 Node* CastX2PNode::Identity(PhaseGVN* phase) { 520 if (in(1)->Opcode() == Op_CastP2X) return in(1)->in(1); 521 return this; 522 } 523 524 //============================================================================= 525 //------------------------------Value------------------------------------------ 526 const Type* CastP2XNode::Value(PhaseGVN* phase) const { 527 const Type* t = phase->type(in(1)); 528 if (t == Type::TOP) return Type::TOP; 529 if (t->base() == Type::RawPtr && t->singleton()) { 530 uintptr_t bits = (uintptr_t) t->is_rawptr()->get_con(); 531 return TypeX::make(bits); 532 } 533 return CastP2XNode::bottom_type(); 534 } 535 536 Node *CastP2XNode::Ideal(PhaseGVN *phase, bool can_reshape) { 537 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : nullptr; 538 } 539 540 //------------------------------Identity--------------------------------------- 541 Node* CastP2XNode::Identity(PhaseGVN* phase) { 542 if (in(1)->Opcode() == Op_CastX2P) return in(1)->in(1); 543 return this; 544 } 545 546 Node* ConstraintCastNode::make_cast_for_type(Node* c, Node* in, const Type* type, DependencyType dependency, 547 const TypeTuple* types) { 548 if (type->isa_int()) { 549 return new CastIINode(c, in, type, dependency, false, types); 550 } else if (type->isa_long()) { 551 return new CastLLNode(c, in, type, dependency, types); 552 } else if (type->isa_half_float()) { 553 return new CastHHNode(c, in, type, dependency, types); 554 } else if (type->isa_float()) { 555 return new CastFFNode(c, in, type, dependency, types); 556 } else if (type->isa_double()) { 557 return new CastDDNode(c, in, type, dependency, types); 558 } else if (type->isa_vect()) { 559 return new CastVVNode(c, in, type, dependency, types); 560 } else if (type->isa_ptr()) { 561 return new CastPPNode(c, in, type, dependency, types); 562 } 563 fatal("unreachable. Invalid cast type."); 564 return nullptr; 565 } 566 567 Node* ConstraintCastNode::optimize_integer_cast(PhaseGVN* phase, BasicType bt) { 568 PhaseIterGVN *igvn = phase->is_IterGVN(); 569 const TypeInteger* this_type = this->type()->isa_integer(bt); 570 if (this_type == nullptr) { 571 return nullptr; 572 } 573 574 Node* z = in(1); 575 const TypeInteger* rx = nullptr; 576 const TypeInteger* ry = nullptr; 577 // Similar to ConvI2LNode::Ideal() for the same reasons 578 if (Compile::push_thru_add(phase, z, this_type, rx, ry, bt, bt)) { 579 if (igvn == nullptr) { 580 // Postpone this optimization to iterative GVN, where we can handle deep 581 // AddI chains without an exponential number of recursive Ideal() calls. 582 phase->record_for_igvn(this); 583 return nullptr; 584 } 585 int op = z->Opcode(); 586 Node* x = z->in(1); 587 Node* y = z->in(2); 588 589 Node* cx = find_or_make_integer_cast(igvn, x, rx); 590 Node* cy = find_or_make_integer_cast(igvn, y, ry); 591 if (op == Op_Add(bt)) { 592 return AddNode::make(cx, cy, bt); 593 } else { 594 assert(op == Op_Sub(bt), ""); 595 return SubNode::make(cx, cy, bt); 596 } 597 return nullptr; 598 } 599 return nullptr; 600 } 601 602 const Type* ConstraintCastNode::widen_type(const PhaseGVN* phase, const Type* res, BasicType bt) const { 603 if (!phase->C->post_loop_opts_phase()) { 604 return res; 605 } 606 607 // At VerifyConstraintCasts == 1, we verify the ConstraintCastNodes that are present during code 608 // emission. This allows us detecting possible mis-scheduling due to these nodes being pinned at 609 // the wrong control nodes. 610 // At VerifyConstraintCasts == 2, we do not perform widening so that we can verify the 611 // correctness of more ConstraintCastNodes. This further helps us detect possible 612 // mis-transformations that may happen due to these nodes being pinned at the wrong control 613 // nodes. 614 if (VerifyConstraintCasts > 1) { 615 return res; 616 } 617 618 const TypeInteger* this_type = res->is_integer(bt); 619 const TypeInteger* in_type = phase->type(in(1))->isa_integer(bt); 620 if (in_type != nullptr && 621 (in_type->lo_as_long() != this_type->lo_as_long() || 622 in_type->hi_as_long() != this_type->hi_as_long())) { 623 jlong lo1 = this_type->lo_as_long(); 624 jlong hi1 = this_type->hi_as_long(); 625 int w1 = this_type->_widen; 626 if (lo1 >= 0) { 627 // Keep a range assertion of >=0. 628 lo1 = 0; hi1 = max_signed_integer(bt); 629 } else if (hi1 < 0) { 630 // Keep a range assertion of <0. 631 lo1 = min_signed_integer(bt); hi1 = -1; 632 } else { 633 lo1 = min_signed_integer(bt); hi1 = max_signed_integer(bt); 634 } 635 return TypeInteger::make(MAX2(in_type->lo_as_long(), lo1), 636 MIN2(in_type->hi_as_long(), hi1), 637 MAX2((int)in_type->_widen, w1), bt); 638 } 639 return res; 640 }