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/castnode.hpp"
28 #include "opto/connode.hpp"
29 #include "opto/matcher.hpp"
30 #include "opto/phaseX.hpp"
31 #include "opto/subnode.hpp"
32 #include "opto/type.hpp"
33
34 //=============================================================================
35 // If input is already higher or equal to cast type, then this is an identity.
36 Node *ConstraintCastNode::Identity( PhaseTransform *phase ) {
37 return phase->type(in(1))->higher_equal_speculative(_type) ? in(1) : this;
38 }
39
40 //------------------------------Value------------------------------------------
41 // Take 'join' of input and cast-up type
42 const Type *ConstraintCastNode::Value( PhaseTransform *phase ) const {
43 if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP;
44 const Type* ft = phase->type(in(1))->filter_speculative(_type);
45
46 #ifdef ASSERT
47 // Previous versions of this function had some special case logic,
48 // which is no longer necessary. Make sure of the required effects.
49 switch (Opcode()) {
50 case Op_CastII:
51 {
52 const Type* t1 = phase->type(in(1));
53 if( t1 == Type::TOP ) assert(ft == Type::TOP, "special case #1");
54 const Type* rt = t1->join_speculative(_type);
55 if (rt->empty()) assert(ft == Type::TOP, "special case #2");
56 break;
57 }
58 case Op_CastPP:
59 if (phase->type(in(1)) == TypePtr::NULL_PTR &&
60 _type->isa_ptr() && _type->is_ptr()->_ptr == TypePtr::NotNull)
61 assert(ft == Type::TOP, "special case #3");
62 break;
63 }
64 #endif //ASSERT
65
66 return ft;
67 }
68
69 //------------------------------Ideal------------------------------------------
70 // Return a node which is more "ideal" than the current node. Strip out
71 // control copies
72 Node *ConstraintCastNode::Ideal(PhaseGVN *phase, bool can_reshape){
73 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : NULL;
74 }
75
76 uint CastIINode::size_of() const {
77 return sizeof(*this);
78 }
79
80 uint CastIINode::cmp(const Node &n) const {
81 return TypeNode::cmp(n) && ((CastIINode&)n)._carry_dependency == _carry_dependency;
82 }
83
84 Node *CastIINode::Identity(PhaseTransform *phase) {
85 if (_carry_dependency) {
86 return this;
87 }
88 return ConstraintCastNode::Identity(phase);
89 }
90
91 const Type *CastIINode::Value(PhaseTransform *phase) const {
92 const Type *res = ConstraintCastNode::Value(phase);
93
94 // Try to improve the type of the CastII if we recognize a CmpI/If
95 // pattern.
96 if (_carry_dependency) {
97 if (in(0) != NULL && in(0)->in(0) != NULL && in(0)->in(0)->is_If()) {
98 assert(in(0)->is_IfFalse() || in(0)->is_IfTrue(), "should be If proj");
99 Node* proj = in(0);
100 if (proj->in(0)->in(1)->is_Bool()) {
101 Node* b = proj->in(0)->in(1);
102 if (b->in(1)->Opcode() == Op_CmpI) {
103 Node* cmp = b->in(1);
104 if (cmp->in(1) == in(1) && phase->type(cmp->in(2))->isa_int()) {
105 const TypeInt* in2_t = phase->type(cmp->in(2))->is_int();
106 const Type* t = TypeInt::INT;
107 BoolTest test = b->as_Bool()->_test;
108 if (proj->is_IfFalse()) {
109 test = test.negate();
110 }
111 BoolTest::mask m = test._test;
112 jlong lo_long = min_jint;
113 jlong hi_long = max_jint;
114 if (m == BoolTest::le || m == BoolTest::lt) {
115 hi_long = in2_t->_hi;
116 if (m == BoolTest::lt) {
117 hi_long -= 1;
118 }
119 } else if (m == BoolTest::ge || m == BoolTest::gt) {
120 lo_long = in2_t->_lo;
121 if (m == BoolTest::gt) {
122 lo_long += 1;
123 }
124 } else if (m == BoolTest::eq) {
125 lo_long = in2_t->_lo;
126 hi_long = in2_t->_hi;
127 } else if (m == BoolTest::ne) {
128 // can't do any better
129 } else {
130 stringStream ss;
131 test.dump_on(&ss);
132 fatal(err_msg_res("unexpected comparison %s", ss.as_string()));
133 }
134 int lo_int = (int)lo_long;
135 int hi_int = (int)hi_long;
136
137 if (lo_long != (jlong)lo_int) {
138 lo_int = min_jint;
139 }
140 if (hi_long != (jlong)hi_int) {
141 hi_int = max_jint;
142 }
143
144 t = TypeInt::make(lo_int, hi_int, Type::WidenMax);
145
146 res = res->filter_speculative(t);
147
148 return res;
149 }
150 }
151 }
152 }
153 }
154 return res;
155 }
156
157 #ifndef PRODUCT
158 void CastIINode::dump_spec(outputStream *st) const {
159 TypeNode::dump_spec(st);
160 if (_carry_dependency) {
161 st->print(" carry dependency");
162 }
163 }
164 #endif
165
166 //=============================================================================
167 //------------------------------Identity---------------------------------------
168 // If input is already higher or equal to cast type, then this is an identity.
169 Node *CheckCastPPNode::Identity( PhaseTransform *phase ) {
170 // Toned down to rescue meeting at a Phi 3 different oops all implementing
171 // the same interface. CompileTheWorld starting at 502, kd12rc1.zip.
172 return (phase->type(in(1)) == phase->type(this)) ? in(1) : this;
173 }
174
175 //------------------------------Value------------------------------------------
176 // Take 'join' of input and cast-up type, unless working with an Interface
177 const Type *CheckCastPPNode::Value( PhaseTransform *phase ) const {
178 if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP;
179
180 const Type *inn = phase->type(in(1));
181 if( inn == Type::TOP ) return Type::TOP; // No information yet
182
183 const TypePtr *in_type = inn->isa_ptr();
184 const TypePtr *my_type = _type->isa_ptr();
185 const Type *result = _type;
186 if( in_type != NULL && my_type != NULL ) {
187 TypePtr::PTR in_ptr = in_type->ptr();
188 if( in_ptr == TypePtr::Null ) {
189 result = in_type;
190 } else if( in_ptr == TypePtr::Constant ) {
191 // Casting a constant oop to an interface?
192 // (i.e., a String to a Comparable?)
193 // Then return the interface.
194 const TypeOopPtr *jptr = my_type->isa_oopptr();
195 assert( jptr, "" );
196 result = (jptr->klass()->is_interface() || !in_type->higher_equal(_type))
197 ? my_type->cast_to_ptr_type( TypePtr::NotNull )
198 : in_type;
199 } else {
200 result = my_type->cast_to_ptr_type( my_type->join_ptr(in_ptr) );
201 }
202 }
203
204 // This is the code from TypePtr::xmeet() that prevents us from
205 // having 2 ways to represent the same type. We have to replicate it
206 // here because we don't go through meet/join.
207 if (result->remove_speculative() == result->speculative()) {
208 result = result->remove_speculative();
209 }
210
211 // Same as above: because we don't go through meet/join, remove the
212 // speculative type if we know we won't use it.
213 return result->cleanup_speculative();
214
215 // JOIN NOT DONE HERE BECAUSE OF INTERFACE ISSUES.
216 // FIX THIS (DO THE JOIN) WHEN UNION TYPES APPEAR!
217
218 //
219 // Remove this code after overnight run indicates no performance
220 // loss from not performing JOIN at CheckCastPPNode
221 //
222 // const TypeInstPtr *in_oop = in->isa_instptr();
223 // const TypeInstPtr *my_oop = _type->isa_instptr();
224 // // If either input is an 'interface', return destination type
225 // assert (in_oop == NULL || in_oop->klass() != NULL, "");
226 // assert (my_oop == NULL || my_oop->klass() != NULL, "");
227 // if( (in_oop && in_oop->klass()->is_interface())
228 // ||(my_oop && my_oop->klass()->is_interface()) ) {
229 // TypePtr::PTR in_ptr = in->isa_ptr() ? in->is_ptr()->_ptr : TypePtr::BotPTR;
230 // // Preserve cast away nullness for interfaces
231 // if( in_ptr == TypePtr::NotNull && my_oop && my_oop->_ptr == TypePtr::BotPTR ) {
232 // return my_oop->cast_to_ptr_type(TypePtr::NotNull);
233 // }
234 // return _type;
235 // }
236 //
237 // // Neither the input nor the destination type is an interface,
238 //
239 // // history: JOIN used to cause weird corner case bugs
240 // // return (in == TypeOopPtr::NULL_PTR) ? in : _type;
241 // // JOIN picks up NotNull in common instance-of/check-cast idioms, both oops.
242 // // JOIN does not preserve NotNull in other cases, e.g. RawPtr vs InstPtr
243 // const Type *join = in->join(_type);
244 // // Check if join preserved NotNull'ness for pointers
245 // if( join->isa_ptr() && _type->isa_ptr() ) {
246 // TypePtr::PTR join_ptr = join->is_ptr()->_ptr;
247 // TypePtr::PTR type_ptr = _type->is_ptr()->_ptr;
248 // // If there isn't any NotNull'ness to preserve
249 // // OR if join preserved NotNull'ness then return it
250 // if( type_ptr == TypePtr::BotPTR || type_ptr == TypePtr::Null ||
251 // join_ptr == TypePtr::NotNull || join_ptr == TypePtr::Constant ) {
252 // return join;
253 // }
254 // // ELSE return same old type as before
255 // return _type;
256 // }
257 // // Not joining two pointers
258 // return join;
259 }
260
261 //------------------------------Ideal------------------------------------------
262 // Return a node which is more "ideal" than the current node. Strip out
263 // control copies
264 Node *CheckCastPPNode::Ideal(PhaseGVN *phase, bool can_reshape){
265 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : NULL;
266 }
267
268 //=============================================================================
269 //------------------------------Value------------------------------------------
270 const Type *CastX2PNode::Value( PhaseTransform *phase ) const {
271 const Type* t = phase->type(in(1));
272 if (t == Type::TOP) return Type::TOP;
273 if (t->base() == Type_X && t->singleton()) {
274 uintptr_t bits = (uintptr_t) t->is_intptr_t()->get_con();
275 if (bits == 0) return TypePtr::NULL_PTR;
276 return TypeRawPtr::make((address) bits);
277 }
278 return CastX2PNode::bottom_type();
279 }
280
281 //------------------------------Idealize---------------------------------------
282 static inline bool fits_in_int(const Type* t, bool but_not_min_int = false) {
283 if (t == Type::TOP) return false;
284 const TypeX* tl = t->is_intptr_t();
285 jint lo = min_jint;
286 jint hi = max_jint;
287 if (but_not_min_int) ++lo; // caller wants to negate the value w/o overflow
288 return (tl->_lo >= lo) && (tl->_hi <= hi);
289 }
290
291 static inline Node* addP_of_X2P(PhaseGVN *phase,
292 Node* base,
293 Node* dispX,
294 bool negate = false) {
295 if (negate) {
296 dispX = new SubXNode(phase->MakeConX(0), phase->transform(dispX));
297 }
298 return new AddPNode(phase->C->top(),
299 phase->transform(new CastX2PNode(base)),
300 phase->transform(dispX));
301 }
302
303 Node *CastX2PNode::Ideal(PhaseGVN *phase, bool can_reshape) {
304 // convert CastX2P(AddX(x, y)) to AddP(CastX2P(x), y) if y fits in an int
305 int op = in(1)->Opcode();
306 Node* x;
307 Node* y;
308 switch (op) {
309 case Op_SubX:
310 x = in(1)->in(1);
311 // Avoid ideal transformations ping-pong between this and AddP for raw pointers.
312 if (phase->find_intptr_t_con(x, -1) == 0)
313 break;
314 y = in(1)->in(2);
315 if (fits_in_int(phase->type(y), true)) {
316 return addP_of_X2P(phase, x, y, true);
317 }
318 break;
319 case Op_AddX:
320 x = in(1)->in(1);
321 y = in(1)->in(2);
322 if (fits_in_int(phase->type(y))) {
323 return addP_of_X2P(phase, x, y);
324 }
325 if (fits_in_int(phase->type(x))) {
326 return addP_of_X2P(phase, y, x);
327 }
328 break;
329 }
330 return NULL;
331 }
332
333 //------------------------------Identity---------------------------------------
334 Node *CastX2PNode::Identity( PhaseTransform *phase ) {
335 if (in(1)->Opcode() == Op_CastP2X) return in(1)->in(1);
336 return this;
337 }
338
339 //=============================================================================
340 //------------------------------Value------------------------------------------
341 const Type *CastP2XNode::Value( PhaseTransform *phase ) const {
342 const Type* t = phase->type(in(1));
343 if (t == Type::TOP) return Type::TOP;
344 if (t->base() == Type::RawPtr && t->singleton()) {
345 uintptr_t bits = (uintptr_t) t->is_rawptr()->get_con();
346 return TypeX::make(bits);
347 }
348 return CastP2XNode::bottom_type();
349 }
350
351 Node *CastP2XNode::Ideal(PhaseGVN *phase, bool can_reshape) {
352 return (in(0) && remove_dead_region(phase, can_reshape)) ? this : NULL;
353 }
354
355 //------------------------------Identity---------------------------------------
356 Node *CastP2XNode::Identity( PhaseTransform *phase ) {
357 if (in(1)->Opcode() == Op_CastX2P) return in(1)->in(1);
358 return this;
359 }