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);
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_CastPP:
67 if (phase->type(in(1)) == TypePtr::NULL_PTR &&
68 _type->isa_ptr() && _type->is_ptr()->_ptr == TypePtr::NotNull)
69 assert(ft == Type::TOP, "special case #3");
70 break;
71 }
72 #endif //ASSERT
73
74 return ft;
75 }
76
77 //------------------------------Ideal------------------------------------------
78 // Return a node which is more "ideal" than the current node. Strip out
79 // control copies
80 Node *ConstraintCastNode::Ideal(PhaseGVN *phase, bool can_reshape) {
81 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : NULL;
82 }
83
84 uint ConstraintCastNode::cmp(const Node &n) const {
85 return TypeNode::cmp(n) && ((ConstraintCastNode&)n)._carry_dependency == _carry_dependency;
86 }
87
88 uint ConstraintCastNode::size_of() const {
89 return sizeof(*this);
90 }
91
92 Node* ConstraintCastNode::make_cast(int opcode, Node* c, Node *n, const Type *t, bool carry_dependency) {
93 switch(opcode) {
94 case Op_CastII: {
95 Node* cast = new CastIINode(n, t, carry_dependency);
96 cast->set_req(0, c);
97 return cast;
98 }
99 case Op_CastPP: {
100 Node* cast = new CastPPNode(n, t, carry_dependency);
101 cast->set_req(0, c);
102 return cast;
103 }
104 case Op_CheckCastPP: return new CheckCastPPNode(c, n, t, carry_dependency);
105 default:
106 fatal("Bad opcode %d", opcode);
107 }
108 return NULL;
109 }
110
111 TypeNode* ConstraintCastNode::dominating_cast(PhaseTransform *phase) const {
112 Node* val = in(1);
113 Node* ctl = in(0);
114 uint opc = Opcode();
115 if (ctl == NULL) {
116 return NULL;
117 }
118 // Range check CastIIs may all end up under a single range check and
119 // in that case only the narrower CastII would be kept by the code
120 // below which would be incorrect.
121 if (is_CastII() && as_CastII()->has_range_check()) {
122 return NULL;
123 }
124 for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
125 Node* u = val->fast_out(i);
126 if (u != this &&
127 u->outcnt() > 0 &&
128 u->Opcode() == opc &&
129 u->in(0) != NULL &&
130 u->bottom_type()->higher_equal(type())) {
131 if (phase->is_dominator(u->in(0), ctl)) {
132 return u->as_Type();
133 }
134 if (is_CheckCastPP() && u->in(1)->is_Proj() && u->in(1)->in(0)->is_Allocate() &&
135 u->in(0)->is_Proj() && u->in(0)->in(0)->is_Initialize() &&
136 u->in(1)->in(0)->as_Allocate()->initialization() == u->in(0)->in(0)) {
137 // CheckCastPP following an allocation always dominates all
138 // use of the allocation result
139 return u->as_Type();
140 }
141 }
142 }
143 return NULL;
144 }
145
146 #ifndef PRODUCT
147 void ConstraintCastNode::dump_spec(outputStream *st) const {
148 TypeNode::dump_spec(st);
149 if (_carry_dependency) {
150 st->print(" carry dependency");
151 }
152 }
153 #endif
154
155 const Type* CastIINode::Value(PhaseGVN* phase) const {
156 const Type *res = ConstraintCastNode::Value(phase);
157
158 // Try to improve the type of the CastII if we recognize a CmpI/If
159 // pattern.
160 if (_carry_dependency) {
161 if (in(0) != NULL && in(0)->in(0) != NULL && in(0)->in(0)->is_If()) {
162 assert(in(0)->is_IfFalse() || in(0)->is_IfTrue(), "should be If proj");
163 Node* proj = in(0);
164 if (proj->in(0)->in(1)->is_Bool()) {
165 Node* b = proj->in(0)->in(1);
166 if (b->in(1)->Opcode() == Op_CmpI) {
167 Node* cmp = b->in(1);
168 if (cmp->in(1) == in(1) && phase->type(cmp->in(2))->isa_int()) {
169 const TypeInt* in2_t = phase->type(cmp->in(2))->is_int();
170 const Type* t = TypeInt::INT;
171 BoolTest test = b->as_Bool()->_test;
172 if (proj->is_IfFalse()) {
173 test = test.negate();
174 }
175 BoolTest::mask m = test._test;
176 jlong lo_long = min_jint;
177 jlong hi_long = max_jint;
178 if (m == BoolTest::le || m == BoolTest::lt) {
179 hi_long = in2_t->_hi;
180 if (m == BoolTest::lt) {
181 hi_long -= 1;
182 }
183 } else if (m == BoolTest::ge || m == BoolTest::gt) {
184 lo_long = in2_t->_lo;
185 if (m == BoolTest::gt) {
186 lo_long += 1;
187 }
188 } else if (m == BoolTest::eq) {
189 lo_long = in2_t->_lo;
190 hi_long = in2_t->_hi;
191 } else if (m == BoolTest::ne) {
192 // can't do any better
193 } else {
194 stringStream ss;
195 test.dump_on(&ss);
196 fatal("unexpected comparison %s", ss.as_string());
197 }
198 int lo_int = (int)lo_long;
199 int hi_int = (int)hi_long;
200
201 if (lo_long != (jlong)lo_int) {
202 lo_int = min_jint;
203 }
204 if (hi_long != (jlong)hi_int) {
205 hi_int = max_jint;
206 }
207
208 t = TypeInt::make(lo_int, hi_int, Type::WidenMax);
209
210 res = res->filter_speculative(t);
211
212 return res;
213 }
214 }
215 }
216 }
217 }
218 return res;
219 }
220
221 Node *CastIINode::Ideal(PhaseGVN *phase, bool can_reshape) {
222 Node* progress = ConstraintCastNode::Ideal(phase, can_reshape);
223 if (progress != NULL) {
224 return progress;
225 }
226
227 // transform:
228 // (CastII (AddI x const)) -> (AddI (CastII x) const)
229 // So the AddI has a chance to be optimized out
230 if (in(1)->Opcode() == Op_AddI) {
231 Node* in2 = in(1)->in(2);
232 const TypeInt* in2_t = phase->type(in2)->isa_int();
233 if (in2_t != NULL && in2_t->singleton()) {
234 int in2_const = in2_t->_lo;
235 const TypeInt* current_type = _type->is_int();
236 jlong new_lo_long = ((jlong)current_type->_lo) - in2_const;
237 jlong new_hi_long = ((jlong)current_type->_hi) - in2_const;
238 int new_lo = (int)new_lo_long;
239 int new_hi = (int)new_hi_long;
240 if (((jlong)new_lo) == new_lo_long && ((jlong)new_hi) == new_hi_long) {
241 Node* in1 = in(1)->in(1);
242 CastIINode* new_cast = (CastIINode*)clone();
243 AddINode* new_add = (AddINode*)in(1)->clone();
244 new_cast->set_type(TypeInt::make(new_lo, new_hi, current_type->_widen));
245 new_cast->set_req(1, in1);
246 new_add->set_req(1, phase->transform(new_cast));
247 return new_add;
248 }
249 }
250 }
251 // Similar to ConvI2LNode::Ideal() for the same reasons
252 if (can_reshape && !phase->C->major_progress()) {
253 const TypeInt* this_type = this->type()->is_int();
254 const TypeInt* in_type = phase->type(in(1))->isa_int();
255 if (in_type != NULL && this_type != NULL &&
256 (in_type->_lo != this_type->_lo ||
257 in_type->_hi != this_type->_hi)) {
258 int lo1 = this_type->_lo;
259 int hi1 = this_type->_hi;
260 int w1 = this_type->_widen;
261
262 if (lo1 >= 0) {
263 // Keep a range assertion of >=0.
264 lo1 = 0; hi1 = max_jint;
265 } else if (hi1 < 0) {
266 // Keep a range assertion of <0.
267 lo1 = min_jint; hi1 = -1;
268 } else {
269 lo1 = min_jint; hi1 = max_jint;
270 }
271 const TypeInt* wtype = TypeInt::make(MAX2(in_type->_lo, lo1),
272 MIN2(in_type->_hi, hi1),
273 MAX2((int)in_type->_widen, w1));
274 if (wtype != type()) {
275 set_type(wtype);
276 return this;
277 }
278 }
279 }
280 return NULL;
281 }
282
283 uint CastIINode::cmp(const Node &n) const {
284 return ConstraintCastNode::cmp(n) && ((CastIINode&)n)._range_check_dependency == _range_check_dependency;
285 }
286
287 uint CastIINode::size_of() const {
288 return sizeof(*this);
289 }
290
291 #ifndef PRODUCT
292 void CastIINode::dump_spec(outputStream* st) const {
293 ConstraintCastNode::dump_spec(st);
294 if (_range_check_dependency) {
295 st->print(" range check dependency");
296 }
297 }
298 #endif
299
300 //=============================================================================
301 //------------------------------Identity---------------------------------------
302 // If input is already higher or equal to cast type, then this is an identity.
303 Node* CheckCastPPNode::Identity(PhaseGVN* phase) {
304 Node* dom = dominating_cast(phase);
305 if (dom != NULL) {
306 return dom;
307 }
308 if (_carry_dependency) {
309 return this;
310 }
311 // Toned down to rescue meeting at a Phi 3 different oops all implementing
312 // the same interface. CompileTheWorld starting at 502, kd12rc1.zip.
313 return (phase->type(in(1)) == phase->type(this)) ? in(1) : this;
314 }
315
316 //------------------------------Value------------------------------------------
317 // Take 'join' of input and cast-up type, unless working with an Interface
318 const Type* CheckCastPPNode::Value(PhaseGVN* phase) const {
319 if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP;
320
321 const Type *inn = phase->type(in(1));
322 if( inn == Type::TOP ) return Type::TOP; // No information yet
323
324 const TypePtr *in_type = inn->isa_ptr();
325 const TypePtr *my_type = _type->isa_ptr();
326 const Type *result = _type;
327 if( in_type != NULL && my_type != NULL ) {
328 TypePtr::PTR in_ptr = in_type->ptr();
329 if (in_ptr == TypePtr::Null) {
330 result = in_type;
331 } else if (in_ptr == TypePtr::Constant) {
332 const TypeOopPtr *jptr = my_type->isa_oopptr();
333 assert(jptr, "");
334 result = !in_type->higher_equal(_type)
335 ? my_type->cast_to_ptr_type(TypePtr::NotNull)
336 : in_type;
337 } else {
338 result = my_type->cast_to_ptr_type( my_type->join_ptr(in_ptr) );
339 }
340 }
341
342 // This is the code from TypePtr::xmeet() that prevents us from
343 // having 2 ways to represent the same type. We have to replicate it
344 // here because we don't go through meet/join.
345 if (result->remove_speculative() == result->speculative()) {
346 result = result->remove_speculative();
347 }
348
349 // Same as above: because we don't go through meet/join, remove the
350 // speculative type if we know we won't use it.
351 return result->cleanup_speculative();
352
353 // JOIN NOT DONE HERE BECAUSE OF INTERFACE ISSUES.
354 // FIX THIS (DO THE JOIN) WHEN UNION TYPES APPEAR!
355
356 //
357 // Remove this code after overnight run indicates no performance
358 // loss from not performing JOIN at CheckCastPPNode
359 //
360 // const TypeInstPtr *in_oop = in->isa_instptr();
361 // const TypeInstPtr *my_oop = _type->isa_instptr();
362 // // If either input is an 'interface', return destination type
363 // assert (in_oop == NULL || in_oop->klass() != NULL, "");
364 // assert (my_oop == NULL || my_oop->klass() != NULL, "");
365 // if( (in_oop && in_oop->klass()->is_interface())
366 // ||(my_oop && my_oop->klass()->is_interface()) ) {
367 // TypePtr::PTR in_ptr = in->isa_ptr() ? in->is_ptr()->_ptr : TypePtr::BotPTR;
368 // // Preserve cast away nullness for interfaces
369 // if( in_ptr == TypePtr::NotNull && my_oop && my_oop->_ptr == TypePtr::BotPTR ) {
370 // return my_oop->cast_to_ptr_type(TypePtr::NotNull);
371 // }
372 // return _type;
373 // }
374 //
375 // // Neither the input nor the destination type is an interface,
376 //
377 // // history: JOIN used to cause weird corner case bugs
378 // // return (in == TypeOopPtr::NULL_PTR) ? in : _type;
379 // // JOIN picks up NotNull in common instance-of/check-cast idioms, both oops.
380 // // JOIN does not preserve NotNull in other cases, e.g. RawPtr vs InstPtr
381 // const Type *join = in->join(_type);
382 // // Check if join preserved NotNull'ness for pointers
383 // if( join->isa_ptr() && _type->isa_ptr() ) {
384 // TypePtr::PTR join_ptr = join->is_ptr()->_ptr;
385 // TypePtr::PTR type_ptr = _type->is_ptr()->_ptr;
386 // // If there isn't any NotNull'ness to preserve
387 // // OR if join preserved NotNull'ness then return it
388 // if( type_ptr == TypePtr::BotPTR || type_ptr == TypePtr::Null ||
389 // join_ptr == TypePtr::NotNull || join_ptr == TypePtr::Constant ) {
390 // return join;
391 // }
392 // // ELSE return same old type as before
393 // return _type;
394 // }
395 // // Not joining two pointers
396 // return join;
397 }
398
399 //=============================================================================
400 //------------------------------Value------------------------------------------
401 const Type* CastX2PNode::Value(PhaseGVN* phase) const {
402 const Type* t = phase->type(in(1));
403 if (t == Type::TOP) return Type::TOP;
404 if (t->base() == Type_X && t->singleton()) {
405 uintptr_t bits = (uintptr_t) t->is_intptr_t()->get_con();
406 if (bits == 0) return TypePtr::NULL_PTR;
407 return TypeRawPtr::make((address) bits);
408 }
409 return CastX2PNode::bottom_type();
410 }
411
412 //------------------------------Idealize---------------------------------------
413 static inline bool fits_in_int(const Type* t, bool but_not_min_int = false) {
414 if (t == Type::TOP) return false;
415 const TypeX* tl = t->is_intptr_t();
416 jint lo = min_jint;
417 jint hi = max_jint;
418 if (but_not_min_int) ++lo; // caller wants to negate the value w/o overflow
419 return (tl->_lo >= lo) && (tl->_hi <= hi);
420 }
421
422 static inline Node* addP_of_X2P(PhaseGVN *phase,
423 Node* base,
424 Node* dispX,
425 bool negate = false) {
426 if (negate) {
427 dispX = new SubXNode(phase->MakeConX(0), phase->transform(dispX));
428 }
429 return new AddPNode(phase->C->top(),
430 phase->transform(new CastX2PNode(base)),
431 phase->transform(dispX));
432 }
433
434 Node *CastX2PNode::Ideal(PhaseGVN *phase, bool can_reshape) {
435 // convert CastX2P(AddX(x, y)) to AddP(CastX2P(x), y) if y fits in an int
436 int op = in(1)->Opcode();
437 Node* x;
438 Node* y;
439 switch (op) {
440 case Op_SubX:
441 x = in(1)->in(1);
442 // Avoid ideal transformations ping-pong between this and AddP for raw pointers.
443 if (phase->find_intptr_t_con(x, -1) == 0)
444 break;
445 y = in(1)->in(2);
446 if (fits_in_int(phase->type(y), true)) {
447 return addP_of_X2P(phase, x, y, true);
448 }
449 break;
450 case Op_AddX:
451 x = in(1)->in(1);
452 y = in(1)->in(2);
453 if (fits_in_int(phase->type(y))) {
454 return addP_of_X2P(phase, x, y);
455 }
456 if (fits_in_int(phase->type(x))) {
457 return addP_of_X2P(phase, y, x);
458 }
459 break;
460 }
461 return NULL;
462 }
463
464 //------------------------------Identity---------------------------------------
465 Node* CastX2PNode::Identity(PhaseGVN* phase) {
466 if (in(1)->Opcode() == Op_CastP2X) return in(1)->in(1);
467 return this;
468 }
469
470 //=============================================================================
471 //------------------------------Value------------------------------------------
472 const Type* CastP2XNode::Value(PhaseGVN* phase) const {
473 const Type* t = phase->type(in(1));
474 if (t == Type::TOP) return Type::TOP;
475 if (t->base() == Type::RawPtr && t->singleton()) {
476 uintptr_t bits = (uintptr_t) t->is_rawptr()->get_con();
477 return TypeX::make(bits);
478 }
479 return CastP2XNode::bottom_type();
480 }
481
482 Node *CastP2XNode::Ideal(PhaseGVN *phase, bool can_reshape) {
483 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : NULL;
484 }
485
486 //------------------------------Identity---------------------------------------
487 Node* CastP2XNode::Identity(PhaseGVN* phase) {
488 if (in(1)->Opcode() == Op_CastX2P) return in(1)->in(1);
489 return this;
490 }