1 /*
2 * Copyright (c) 2014, 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/matcher.hpp"
31 #include "opto/phaseX.hpp"
32 #include "opto/subnode.hpp"
33 #include "opto/type.hpp"
34
35 //=============================================================================
36 // If input is already higher or equal to cast type, then this is an identity.
37 Node* ConstraintCastNode::Identity(PhaseGVN* phase) {
38 Node* dom = dominating_cast(phase, phase);
39 if (dom != NULL) {
40 return dom;
41 }
42 if (_carry_dependency) {
43 return this;
44 }
45 return phase->type(in(1))->higher_equal_speculative(_type) ? in(1) : this;
46 }
47
48 //------------------------------Value------------------------------------------
49 // Take 'join' of input and cast-up type
50 const Type* ConstraintCastNode::Value(PhaseGVN* phase) const {
51 if (in(0) && phase->type(in(0)) == Type::TOP) return Type::TOP;
52 const Type* ft = phase->type(in(1))->filter_speculative(_type);
53
54 #ifdef ASSERT
55 // Previous versions of this function had some special case logic,
56 // which is no longer necessary. Make sure of the required effects.
57 switch (Opcode()) {
58 case Op_CastII:
59 {
60 const Type* t1 = phase->type(in(1));
61 if( t1 == Type::TOP ) assert(ft == Type::TOP, "special case #1");
62 const Type* rt = t1->join_speculative(_type);
63 if (rt->empty()) assert(ft == Type::TOP, "special case #2");
64 break;
65 }
66 case Op_CastLL:
67 {
68 const Type* t1 = phase->type(in(1));
69 if (t1 == Type::TOP) assert(ft == Type::TOP, "special case #1");
70 const Type* rt = t1->join_speculative(_type);
71 if (rt->empty()) assert(ft == Type::TOP, "special case #2");
72 break;
73 }
74 case Op_CastPP:
75 if (phase->type(in(1)) == TypePtr::NULL_PTR &&
76 _type->isa_ptr() && _type->is_ptr()->_ptr == TypePtr::NotNull)
77 assert(ft == Type::TOP, "special case #3");
78 break;
79 }
80 #endif //ASSERT
81
82 return ft;
83 }
84
85 //------------------------------Ideal------------------------------------------
86 // Return a node which is more "ideal" than the current node. Strip out
87 // control copies
88 Node *ConstraintCastNode::Ideal(PhaseGVN *phase, bool can_reshape) {
89 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : NULL;
90 }
91
92 bool ConstraintCastNode::cmp(const Node &n) const {
93 return TypeNode::cmp(n) && ((ConstraintCastNode&)n)._carry_dependency == _carry_dependency;
94 }
95
96 uint ConstraintCastNode::size_of() const {
97 return sizeof(*this);
98 }
99
100 Node* ConstraintCastNode::make_cast(int opcode, Node* c, Node *n, const Type *t, bool carry_dependency) {
101 switch(opcode) {
102 case Op_CastII: {
103 Node* cast = new CastIINode(n, t, carry_dependency);
104 cast->set_req(0, c);
105 return cast;
106 }
107 case Op_CastLL: {
108 Node* cast = new CastLLNode(n, t, carry_dependency);
109 cast->set_req(0, c);
110 return cast;
111 }
112 case Op_CastPP: {
113 Node* cast = new CastPPNode(n, t, carry_dependency);
114 cast->set_req(0, c);
115 return cast;
116 }
117 case Op_CheckCastPP: return new CheckCastPPNode(c, n, t, carry_dependency);
118 default:
119 fatal("Bad opcode %d", opcode);
120 }
121 return NULL;
122 }
123
124 TypeNode* ConstraintCastNode::dominating_cast(PhaseGVN* gvn, PhaseTransform* pt) const {
125 Node* val = in(1);
126 Node* ctl = in(0);
127 int opc = Opcode();
128 if (ctl == NULL) {
129 return NULL;
130 }
131 // Range check CastIIs may all end up under a single range check and
132 // in that case only the narrower CastII would be kept by the code
133 // below which would be incorrect.
134 if (is_CastII() && as_CastII()->has_range_check()) {
135 return NULL;
136 }
137 if (type()->isa_rawptr() && (gvn->type_or_null(val) == NULL || gvn->type(val)->isa_oopptr())) {
138 return NULL;
139 }
140 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
141 Node* u = val->fast_out(i);
142 if (u != this &&
143 u->outcnt() > 0 &&
144 u->Opcode() == opc &&
145 u->in(0) != NULL &&
146 u->bottom_type()->higher_equal(type())) {
147 if (pt->is_dominator(u->in(0), ctl)) {
148 return u->as_Type();
149 }
150 if (is_CheckCastPP() && u->in(1)->is_Proj() && u->in(1)->in(0)->is_Allocate() &&
151 u->in(0)->is_Proj() && u->in(0)->in(0)->is_Initialize() &&
152 u->in(1)->in(0)->as_Allocate()->initialization() == u->in(0)->in(0)) {
153 // CheckCastPP following an allocation always dominates all
154 // use of the allocation result
155 return u->as_Type();
156 }
157 }
158 }
159 return NULL;
160 }
161
162 #ifndef PRODUCT
163 void ConstraintCastNode::dump_spec(outputStream *st) const {
164 TypeNode::dump_spec(st);
165 if (_carry_dependency) {
166 st->print(" carry dependency");
167 }
168 }
169 #endif
170
171 const Type* CastIINode::Value(PhaseGVN* phase) const {
172 const Type *res = ConstraintCastNode::Value(phase);
173
174 // Try to improve the type of the CastII if we recognize a CmpI/If
175 // pattern.
176 if (_carry_dependency) {
177 if (in(0) != NULL && in(0)->in(0) != NULL && in(0)->in(0)->is_If()) {
178 assert(in(0)->is_IfFalse() || in(0)->is_IfTrue(), "should be If proj");
179 Node* proj = in(0);
180 if (proj->in(0)->in(1)->is_Bool()) {
181 Node* b = proj->in(0)->in(1);
182 if (b->in(1)->Opcode() == Op_CmpI) {
183 Node* cmp = b->in(1);
184 if (cmp->in(1) == in(1) && phase->type(cmp->in(2))->isa_int()) {
185 const TypeInt* in2_t = phase->type(cmp->in(2))->is_int();
186 const Type* t = TypeInt::INT;
187 BoolTest test = b->as_Bool()->_test;
188 if (proj->is_IfFalse()) {
189 test = test.negate();
190 }
191 BoolTest::mask m = test._test;
192 jlong lo_long = min_jint;
193 jlong hi_long = max_jint;
194 if (m == BoolTest::le || m == BoolTest::lt) {
195 hi_long = in2_t->_hi;
196 if (m == BoolTest::lt) {
197 hi_long -= 1;
198 }
199 } else if (m == BoolTest::ge || m == BoolTest::gt) {
200 lo_long = in2_t->_lo;
201 if (m == BoolTest::gt) {
202 lo_long += 1;
203 }
204 } else if (m == BoolTest::eq) {
205 lo_long = in2_t->_lo;
206 hi_long = in2_t->_hi;
207 } else if (m == BoolTest::ne) {
208 // can't do any better
209 } else {
210 stringStream ss;
211 test.dump_on(&ss);
212 fatal("unexpected comparison %s", ss.as_string());
213 }
214 int lo_int = (int)lo_long;
215 int hi_int = (int)hi_long;
216
217 if (lo_long != (jlong)lo_int) {
218 lo_int = min_jint;
219 }
220 if (hi_long != (jlong)hi_int) {
221 hi_int = max_jint;
222 }
223
224 t = TypeInt::make(lo_int, hi_int, Type::WidenMax);
225
226 res = res->filter_speculative(t);
227
228 return res;
229 }
230 }
231 }
232 }
233 }
234 return res;
235 }
236
237 Node *CastIINode::Ideal(PhaseGVN *phase, bool can_reshape) {
238 Node* progress = ConstraintCastNode::Ideal(phase, can_reshape);
239 if (progress != NULL) {
240 return progress;
241 }
242
243 // Similar to ConvI2LNode::Ideal() for the same reasons
244 // Do not narrow the type of range check dependent CastIINodes to
245 // avoid corruption of the graph if a CastII is replaced by TOP but
246 // the corresponding range check is not removed.
247 if (can_reshape && !_range_check_dependency && !phase->C->major_progress()) {
248 const TypeInt* this_type = this->type()->is_int();
249 const TypeInt* in_type = phase->type(in(1))->isa_int();
250 if (in_type != NULL && this_type != NULL &&
251 (in_type->_lo != this_type->_lo ||
252 in_type->_hi != this_type->_hi)) {
253 jint lo1 = this_type->_lo;
254 jint hi1 = this_type->_hi;
255 int w1 = this_type->_widen;
256
257 if (lo1 >= 0) {
258 // Keep a range assertion of >=0.
259 lo1 = 0; hi1 = max_jint;
260 } else if (hi1 < 0) {
261 // Keep a range assertion of <0.
262 lo1 = min_jint; hi1 = -1;
263 } else {
264 lo1 = min_jint; hi1 = max_jint;
265 }
266 const TypeInt* wtype = TypeInt::make(MAX2(in_type->_lo, lo1),
267 MIN2(in_type->_hi, hi1),
268 MAX2((int)in_type->_widen, w1));
269 if (wtype != type()) {
270 set_type(wtype);
271 return this;
272 }
273 }
274 }
275 return NULL;
276 }
277
278 bool CastIINode::cmp(const Node &n) const {
279 return ConstraintCastNode::cmp(n) && ((CastIINode&)n)._range_check_dependency == _range_check_dependency;
280 }
281
282 uint CastIINode::size_of() const {
283 return sizeof(*this);
284 }
285
286 #ifndef PRODUCT
287 void CastIINode::dump_spec(outputStream* st) const {
288 ConstraintCastNode::dump_spec(st);
289 if (_range_check_dependency) {
290 st->print(" range check dependency");
291 }
292 }
293 #endif
294
295 Node* CastLLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
296 Node* progress = ConstraintCastNode::Ideal(phase, can_reshape);
297 if (progress != NULL) {
298 return progress;
299 }
300
301 // Same as in CastIINode::Ideal but for TypeLong instead of TypeInt
302 if (can_reshape && !phase->C->major_progress()) {
303 const TypeLong* this_type = this->type()->is_long();
304 const TypeLong* in_type = phase->type(in(1))->isa_long();
305 if (in_type != NULL && this_type != NULL &&
306 (in_type->_lo != this_type->_lo ||
307 in_type->_hi != this_type->_hi)) {
308 jlong lo1 = this_type->_lo;
309 jlong hi1 = this_type->_hi;
310 int w1 = this_type->_widen;
311
312 if (lo1 >= 0) {
313 // Keep a range assertion of >=0.
314 lo1 = 0; hi1 = max_jlong;
315 } else if (hi1 < 0) {
316 // Keep a range assertion of <0.
317 lo1 = min_jlong; hi1 = -1;
318 } else {
319 lo1 = min_jlong; hi1 = max_jlong;
320 }
321 const TypeLong* wtype = TypeLong::make(MAX2(in_type->_lo, lo1),
322 MIN2(in_type->_hi, hi1),
323 MAX2((int)in_type->_widen, w1));
324 if (wtype != type()) {
325 set_type(wtype);
326 return this;
327 }
328 }
329 }
330 return NULL;
331 }
332
333
334 //=============================================================================
335 //------------------------------Identity---------------------------------------
336 // If input is already higher or equal to cast type, then this is an identity.
337 Node* CheckCastPPNode::Identity(PhaseGVN* phase) {
338 Node* dom = dominating_cast(phase, phase);
339 if (dom != NULL) {
340 return dom;
341 }
342 if (_carry_dependency) {
343 return this;
344 }
345 const Type* t = phase->type(in(1));
346 if (EnableVectorReboxing && in(1)->Opcode() == Op_VectorBox) {
347 return t->higher_equal_speculative(phase->type(this)) ? in(1) : this;
348 } else {
349 // Toned down to rescue meeting at a Phi 3 different oops all implementing
350 // the same interface.
351 return (t == phase->type(this)) ? in(1) : this;
352 }
353 }
354
355 //------------------------------Value------------------------------------------
356 // Take 'join' of input and cast-up type, unless working with an Interface
357 const Type* CheckCastPPNode::Value(PhaseGVN* phase) const {
358 if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP;
359
360 const Type *inn = phase->type(in(1));
361 if( inn == Type::TOP ) return Type::TOP; // No information yet
362
363 const TypePtr *in_type = inn->isa_ptr();
364 const TypePtr *my_type = _type->isa_ptr();
365 const Type *result = _type;
366 if( in_type != NULL && my_type != NULL ) {
367 TypePtr::PTR in_ptr = in_type->ptr();
368 if (in_ptr == TypePtr::Null) {
369 result = in_type;
370 } else if (in_ptr == TypePtr::Constant) {
371 if (my_type->isa_rawptr()) {
372 result = my_type;
373 } else {
374 const TypeOopPtr *jptr = my_type->isa_oopptr();
375 assert(jptr, "");
376 result = !in_type->higher_equal(_type)
377 ? my_type->cast_to_ptr_type(TypePtr::NotNull)
378 : in_type;
379 }
380 } else {
381 result = my_type->cast_to_ptr_type( my_type->join_ptr(in_ptr) );
382 }
383 }
384
385 // This is the code from TypePtr::xmeet() that prevents us from
386 // having 2 ways to represent the same type. We have to replicate it
387 // here because we don't go through meet/join.
388 if (result->remove_speculative() == result->speculative()) {
389 result = result->remove_speculative();
390 }
391
392 // Same as above: because we don't go through meet/join, remove the
393 // speculative type if we know we won't use it.
394 return result->cleanup_speculative();
395
396 // JOIN NOT DONE HERE BECAUSE OF INTERFACE ISSUES.
397 // FIX THIS (DO THE JOIN) WHEN UNION TYPES APPEAR!
398
399 //
400 // Remove this code after overnight run indicates no performance
401 // loss from not performing JOIN at CheckCastPPNode
402 //
403 // const TypeInstPtr *in_oop = in->isa_instptr();
404 // const TypeInstPtr *my_oop = _type->isa_instptr();
405 // // If either input is an 'interface', return destination type
406 // assert (in_oop == NULL || in_oop->klass() != NULL, "");
407 // assert (my_oop == NULL || my_oop->klass() != NULL, "");
408 // if( (in_oop && in_oop->klass()->is_interface())
409 // ||(my_oop && my_oop->klass()->is_interface()) ) {
410 // TypePtr::PTR in_ptr = in->isa_ptr() ? in->is_ptr()->_ptr : TypePtr::BotPTR;
411 // // Preserve cast away nullness for interfaces
412 // if( in_ptr == TypePtr::NotNull && my_oop && my_oop->_ptr == TypePtr::BotPTR ) {
413 // return my_oop->cast_to_ptr_type(TypePtr::NotNull);
414 // }
415 // return _type;
416 // }
417 //
418 // // Neither the input nor the destination type is an interface,
419 //
420 // // history: JOIN used to cause weird corner case bugs
421 // // return (in == TypeOopPtr::NULL_PTR) ? in : _type;
422 // // JOIN picks up NotNull in common instance-of/check-cast idioms, both oops.
423 // // JOIN does not preserve NotNull in other cases, e.g. RawPtr vs InstPtr
424 // const Type *join = in->join(_type);
425 // // Check if join preserved NotNull'ness for pointers
426 // if( join->isa_ptr() && _type->isa_ptr() ) {
427 // TypePtr::PTR join_ptr = join->is_ptr()->_ptr;
428 // TypePtr::PTR type_ptr = _type->is_ptr()->_ptr;
429 // // If there isn't any NotNull'ness to preserve
430 // // OR if join preserved NotNull'ness then return it
431 // if( type_ptr == TypePtr::BotPTR || type_ptr == TypePtr::Null ||
432 // join_ptr == TypePtr::NotNull || join_ptr == TypePtr::Constant ) {
433 // return join;
434 // }
435 // // ELSE return same old type as before
436 // return _type;
437 // }
438 // // Not joining two pointers
439 // return join;
440 }
441
442 //=============================================================================
443 //------------------------------Value------------------------------------------
444 const Type* CastX2PNode::Value(PhaseGVN* phase) const {
445 const Type* t = phase->type(in(1));
446 if (t == Type::TOP) return Type::TOP;
447 if (t->base() == Type_X && t->singleton()) {
448 uintptr_t bits = (uintptr_t) t->is_intptr_t()->get_con();
449 if (bits == 0) return TypePtr::NULL_PTR;
450 return TypeRawPtr::make((address) bits);
451 }
452 return CastX2PNode::bottom_type();
453 }
454
455 //------------------------------Idealize---------------------------------------
456 static inline bool fits_in_int(const Type* t, bool but_not_min_int = false) {
457 if (t == Type::TOP) return false;
458 const TypeX* tl = t->is_intptr_t();
459 jint lo = min_jint;
460 jint hi = max_jint;
461 if (but_not_min_int) ++lo; // caller wants to negate the value w/o overflow
462 return (tl->_lo >= lo) && (tl->_hi <= hi);
463 }
464
465 static inline Node* addP_of_X2P(PhaseGVN *phase,
466 Node* base,
467 Node* dispX,
468 bool negate = false) {
469 if (negate) {
470 dispX = phase->transform(new SubXNode(phase->MakeConX(0), dispX));
471 }
472 return new AddPNode(phase->C->top(),
473 phase->transform(new CastX2PNode(base)),
474 dispX);
475 }
476
477 Node *CastX2PNode::Ideal(PhaseGVN *phase, bool can_reshape) {
478 // convert CastX2P(AddX(x, y)) to AddP(CastX2P(x), y) if y fits in an int
479 int op = in(1)->Opcode();
480 Node* x;
481 Node* y;
482 switch (op) {
483 case Op_SubX:
484 x = in(1)->in(1);
485 // Avoid ideal transformations ping-pong between this and AddP for raw pointers.
486 if (phase->find_intptr_t_con(x, -1) == 0)
487 break;
488 y = in(1)->in(2);
489 if (fits_in_int(phase->type(y), true)) {
490 return addP_of_X2P(phase, x, y, true);
491 }
492 break;
493 case Op_AddX:
494 x = in(1)->in(1);
495 y = in(1)->in(2);
496 if (fits_in_int(phase->type(y))) {
497 return addP_of_X2P(phase, x, y);
498 }
499 if (fits_in_int(phase->type(x))) {
500 return addP_of_X2P(phase, y, x);
501 }
502 break;
503 }
504 return NULL;
505 }
506
507 //------------------------------Identity---------------------------------------
508 Node* CastX2PNode::Identity(PhaseGVN* phase) {
509 if (in(1)->Opcode() == Op_CastP2X) return in(1)->in(1);
510 return this;
511 }
512
513 //=============================================================================
514 //------------------------------Value------------------------------------------
515 const Type* CastP2XNode::Value(PhaseGVN* phase) const {
516 const Type* t = phase->type(in(1));
517 if (t == Type::TOP) return Type::TOP;
518 if (t->base() == Type::RawPtr && t->singleton()) {
519 uintptr_t bits = (uintptr_t) t->is_rawptr()->get_con();
520 return TypeX::make(bits);
521 }
522 return CastP2XNode::bottom_type();
523 }
524
525 Node *CastP2XNode::Ideal(PhaseGVN *phase, bool can_reshape) {
526 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : NULL;
527 }
528
529 //------------------------------Identity---------------------------------------
530 Node* CastP2XNode::Identity(PhaseGVN* phase) {
531 if (in(1)->Opcode() == Op_CastX2P) return in(1)->in(1);
532 return this;
533 }