1 /*
2 * Copyright (c) 1998, 2013, 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 "compiler/compileLog.hpp"
27 #include "interpreter/linkResolver.hpp"
28 #include "memory/universe.inline.hpp"
29 #include "oops/objArrayKlass.hpp"
30 #include "opto/addnode.hpp"
31 #include "opto/memnode.hpp"
32 #include "opto/parse.hpp"
33 #include "opto/rootnode.hpp"
34 #include "opto/runtime.hpp"
35 #include "opto/subnode.hpp"
36 #include "runtime/deoptimization.hpp"
37 #include "runtime/handles.inline.hpp"
38
39 //=============================================================================
40 // Helper methods for _get* and _put* bytecodes
41 //=============================================================================
42 bool Parse::static_field_ok_in_clinit(ciField *field, ciMethod *method) {
43 // Could be the field_holder's <clinit> method, or <clinit> for a subklass.
44 // Better to check now than to Deoptimize as soon as we execute
45 assert( field->is_static(), "Only check if field is static");
46 // is_being_initialized() is too generous. It allows access to statics
47 // by threads that are not running the <clinit> before the <clinit> finishes.
48 // return field->holder()->is_being_initialized();
49
50 // The following restriction is correct but conservative.
51 // It is also desirable to allow compilation of methods called from <clinit>
52 // but this generated code will need to be made safe for execution by
53 // other threads, or the transition from interpreted to compiled code would
54 // need to be guarded.
55 ciInstanceKlass *field_holder = field->holder();
56
57 bool access_OK = false;
58 if (method->holder()->is_subclass_of(field_holder)) {
59 if (method->is_static()) {
60 if (method->name() == ciSymbol::class_initializer_name()) {
61 // OK to access static fields inside initializer
62 access_OK = true;
63 }
64 } else {
65 if (method->name() == ciSymbol::object_initializer_name()) {
66 // It's also OK to access static fields inside a constructor,
67 // because any thread calling the constructor must first have
68 // synchronized on the class by executing a '_new' bytecode.
69 access_OK = true;
70 }
71 }
72 }
73
74 return access_OK;
75
76 }
77
78
79 void Parse::do_field_access(bool is_get, bool is_field) {
80 bool will_link;
81 ciField* field = iter().get_field(will_link);
82 assert(will_link, "getfield: typeflow responsibility");
83
84 ciInstanceKlass* field_holder = field->holder();
85
86 if (is_field == field->is_static()) {
87 // Interpreter will throw java_lang_IncompatibleClassChangeError
88 // Check this before allowing <clinit> methods to access static fields
89 uncommon_trap(Deoptimization::Reason_unhandled,
90 Deoptimization::Action_none);
91 return;
92 }
93
94 if (!is_field && !field_holder->is_initialized()) {
95 if (!static_field_ok_in_clinit(field, method())) {
96 uncommon_trap(Deoptimization::Reason_uninitialized,
97 Deoptimization::Action_reinterpret,
98 NULL, "!static_field_ok_in_clinit");
99 return;
100 }
101 }
102
103 // Deoptimize on putfield writes to call site target field.
104 if (!is_get && field->is_call_site_target()) {
105 uncommon_trap(Deoptimization::Reason_unhandled,
106 Deoptimization::Action_reinterpret,
107 NULL, "put to call site target field");
108 return;
109 }
110
111 assert(field->will_link(method()->holder(), bc()), "getfield: typeflow responsibility");
112
113 // Note: We do not check for an unloaded field type here any more.
114
115 // Generate code for the object pointer.
116 Node* obj;
117 if (is_field) {
118 int obj_depth = is_get ? 0 : field->type()->size();
119 obj = null_check(peek(obj_depth));
120 // Compile-time detect of null-exception?
121 if (stopped()) return;
122
123 #ifdef ASSERT
124 const TypeInstPtr *tjp = TypeInstPtr::make(TypePtr::NotNull, iter().get_declared_field_holder());
125 assert(_gvn.type(obj)->higher_equal(tjp), "cast_up is no longer needed");
126 #endif
127
128 if (is_get) {
129 (void) pop(); // pop receiver before getting
130 do_get_xxx(obj, field, is_field);
131 } else {
132 do_put_xxx(obj, field, is_field);
133 (void) pop(); // pop receiver after putting
134 }
135 } else {
136 const TypeInstPtr* tip = TypeInstPtr::make(field_holder->java_mirror());
137 obj = _gvn.makecon(tip);
138 if (is_get) {
139 do_get_xxx(obj, field, is_field);
140 } else {
141 do_put_xxx(obj, field, is_field);
142 }
143 }
144 }
145
146
147 void Parse::do_get_xxx(Node* obj, ciField* field, bool is_field) {
148 // Does this field have a constant value? If so, just push the value.
149 if (field->is_constant()) {
150 // final or stable field
151 const Type* stable_type = NULL;
152 if (FoldStableValues && field->is_stable()) {
153 stable_type = Type::get_const_type(field->type());
154 if (field->type()->is_array_klass()) {
155 int stable_dimension = field->type()->as_array_klass()->dimension();
156 stable_type = stable_type->is_aryptr()->cast_to_stable(true, stable_dimension);
157 }
158 }
159 if (field->is_static()) {
160 // final static field
161 if (C->eliminate_boxing()) {
162 // The pointers in the autobox arrays are always non-null.
163 ciSymbol* klass_name = field->holder()->name();
164 if (field->name() == ciSymbol::cache_field_name() &&
165 field->holder()->uses_default_loader() &&
166 (klass_name == ciSymbol::java_lang_Character_CharacterCache() ||
167 klass_name == ciSymbol::java_lang_Byte_ByteCache() ||
168 klass_name == ciSymbol::java_lang_Short_ShortCache() ||
169 klass_name == ciSymbol::java_lang_Integer_IntegerCache() ||
170 klass_name == ciSymbol::java_lang_Long_LongCache())) {
171 bool require_const = true;
172 bool autobox_cache = true;
173 if (push_constant(field->constant_value(), require_const, autobox_cache)) {
174 return;
175 }
176 }
177 }
178 if (push_constant(field->constant_value(), false, false, stable_type))
179 return;
180 } else {
181 // final or stable non-static field
182 // Treat final non-static fields of trusted classes (classes in
183 // java.lang.invoke and sun.invoke packages and subpackages) as
184 // compile time constants.
185 if (obj->is_Con()) {
186 const TypeOopPtr* oop_ptr = obj->bottom_type()->isa_oopptr();
187 ciObject* constant_oop = oop_ptr->const_oop();
188 ciConstant constant = field->constant_value_of(constant_oop);
189 if (FoldStableValues && field->is_stable() && constant.is_null_or_zero()) {
190 // fall through to field load; the field is not yet initialized
191 } else {
192 if (push_constant(constant, true, false, stable_type))
193 return;
194 }
195 }
196 }
197 }
198
199 ciType* field_klass = field->type();
200 bool is_vol = field->is_volatile();
201
202 // Compute address and memory type.
203 int offset = field->offset_in_bytes();
204 const TypePtr* adr_type = C->alias_type(field)->adr_type();
205 Node *adr = basic_plus_adr(obj, obj, offset);
206 BasicType bt = field->layout_type();
207
208 // Build the resultant type of the load
209 const Type *type;
210
211 bool must_assert_null = false;
212
213 if( bt == T_OBJECT ) {
214 if (!field->type()->is_loaded()) {
215 type = TypeInstPtr::BOTTOM;
216 must_assert_null = true;
217 } else if (field->is_constant() && field->is_static()) {
218 // This can happen if the constant oop is non-perm.
219 ciObject* con = field->constant_value().as_object();
220 // Do not "join" in the previous type; it doesn't add value,
221 // and may yield a vacuous result if the field is of interface type.
222 type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
223 assert(type != NULL, "field singleton type must be consistent");
224 } else {
225 type = TypeOopPtr::make_from_klass(field_klass->as_klass());
226 }
227 } else {
228 type = Type::get_const_basic_type(bt);
229 }
230 // Build the load.
231 Node* ld = make_load(NULL, adr, type, bt, adr_type, is_vol);
232
233 // Adjust Java stack
234 if (type2size[bt] == 1)
235 push(ld);
236 else
237 push_pair(ld);
238
239 if (must_assert_null) {
240 // Do not take a trap here. It's possible that the program
241 // will never load the field's class, and will happily see
242 // null values in this field forever. Don't stumble into a
243 // trap for such a program, or we might get a long series
244 // of useless recompilations. (Or, we might load a class
245 // which should not be loaded.) If we ever see a non-null
246 // value, we will then trap and recompile. (The trap will
247 // not need to mention the class index, since the class will
248 // already have been loaded if we ever see a non-null value.)
249 // uncommon_trap(iter().get_field_signature_index());
250 #ifndef PRODUCT
251 if (PrintOpto && (Verbose || WizardMode)) {
252 method()->print_name(); tty->print_cr(" asserting nullness of field at bci: %d", bci());
253 }
254 #endif
255 if (C->log() != NULL) {
256 C->log()->elem("assert_null reason='field' klass='%d'",
257 C->log()->identify(field->type()));
258 }
259 // If there is going to be a trap, put it at the next bytecode:
260 set_bci(iter().next_bci());
261 null_assert(peek());
262 set_bci(iter().cur_bci()); // put it back
263 }
264
265 // If reference is volatile, prevent following memory ops from
266 // floating up past the volatile read. Also prevents commoning
267 // another volatile read.
268 if (field->is_volatile()) {
269 // Memory barrier includes bogus read of value to force load BEFORE membar
270 insert_mem_bar(Op_MemBarAcquire, ld);
271 }
272 }
273
274 void Parse::do_put_xxx(Node* obj, ciField* field, bool is_field) {
275 bool is_vol = field->is_volatile();
276 // If reference is volatile, prevent following memory ops from
277 // floating down past the volatile write. Also prevents commoning
278 // another volatile read.
279 if (is_vol) insert_mem_bar(Op_MemBarRelease);
280
281 // Compute address and memory type.
282 int offset = field->offset_in_bytes();
283 const TypePtr* adr_type = C->alias_type(field)->adr_type();
284 Node* adr = basic_plus_adr(obj, obj, offset);
285 BasicType bt = field->layout_type();
286 // Value to be stored
287 Node* val = type2size[bt] == 1 ? pop() : pop_pair();
288 // Round doubles before storing
289 if (bt == T_DOUBLE) val = dstore_rounding(val);
290
291 // Store the value.
292 Node* store;
293 if (bt == T_OBJECT) {
294 const TypeOopPtr* field_type;
295 if (!field->type()->is_loaded()) {
296 field_type = TypeInstPtr::BOTTOM;
297 } else {
298 field_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
299 }
300 store = store_oop_to_object( control(), obj, adr, adr_type, val, field_type, bt);
301 } else {
302 store = store_to_memory( control(), adr, val, bt, adr_type, is_vol );
303 }
304
305 // If reference is volatile, prevent following volatiles ops from
306 // floating up before the volatile write.
307 if (is_vol) {
308 insert_mem_bar(Op_MemBarVolatile); // Use fat membar
309 }
310
311 // If the field is final, the rules of Java say we are in <init> or <clinit>.
312 // Note the presence of writes to final non-static fields, so that we
313 // can insert a memory barrier later on to keep the writes from floating
314 // out of the constructor.
315 // Any method can write a @Stable field; insert memory barriers after those also.
316 if (is_field && (field->is_final() || field->is_stable())) {
317 set_wrote_final(true);
318 // Preserve allocation ptr to create precedent edge to it in membar
319 // generated on exit from constructor.
320 if (C->eliminate_boxing() &&
321 adr_type->isa_oopptr() && adr_type->is_oopptr()->is_ptr_to_boxed_value() &&
322 AllocateNode::Ideal_allocation(obj, &_gvn) != NULL) {
323 set_alloc_with_final(obj);
324 }
325 }
326 }
327
328
329
330 bool Parse::push_constant(ciConstant constant, bool require_constant, bool is_autobox_cache, const Type* stable_type) {
331 const Type* con_type = Type::make_from_constant(constant, require_constant, is_autobox_cache);
332 switch (constant.basic_type()) {
333 case T_ARRAY:
334 case T_OBJECT:
335 // cases:
336 // can_be_constant = (oop not scavengable || ScavengeRootsInCode != 0)
337 // should_be_constant = (oop not scavengable || ScavengeRootsInCode >= 2)
338 // An oop is not scavengable if it is in the perm gen.
339 if (stable_type != NULL && con_type != NULL && con_type->isa_oopptr())
340 con_type = con_type->join(stable_type);
341 break;
342
343 case T_ILLEGAL:
344 // Invalid ciConstant returned due to OutOfMemoryError in the CI
345 assert(C->env()->failing(), "otherwise should not see this");
346 // These always occur because of object types; we are going to
347 // bail out anyway, so make the stack depths match up
348 push( zerocon(T_OBJECT) );
349 return false;
350 }
351
352 if (con_type == NULL)
353 // we cannot inline the oop, but we can use it later to narrow a type
354 return false;
355
356 push_node(constant.basic_type(), makecon(con_type));
357 return true;
358 }
359
360
361 //=============================================================================
362 void Parse::do_anewarray() {
363 bool will_link;
364 ciKlass* klass = iter().get_klass(will_link);
365
366 // Uncommon Trap when class that array contains is not loaded
367 // we need the loaded class for the rest of graph; do not
368 // initialize the container class (see Java spec)!!!
369 assert(will_link, "anewarray: typeflow responsibility");
370
371 ciObjArrayKlass* array_klass = ciObjArrayKlass::make(klass);
372 // Check that array_klass object is loaded
373 if (!array_klass->is_loaded()) {
374 // Generate uncommon_trap for unloaded array_class
375 uncommon_trap(Deoptimization::Reason_unloaded,
376 Deoptimization::Action_reinterpret,
377 array_klass);
378 return;
379 }
380
381 kill_dead_locals();
382
383 const TypeKlassPtr* array_klass_type = TypeKlassPtr::make(array_klass);
384 Node* count_val = pop();
385 Node* obj = new_array(makecon(array_klass_type), count_val, 1);
386 push(obj);
387 }
388
389
390 void Parse::do_newarray(BasicType elem_type) {
391 kill_dead_locals();
392
393 Node* count_val = pop();
394 const TypeKlassPtr* array_klass = TypeKlassPtr::make(ciTypeArrayKlass::make(elem_type));
395 Node* obj = new_array(makecon(array_klass), count_val, 1);
396 // Push resultant oop onto stack
397 push(obj);
398 }
399
400 // Expand simple expressions like new int[3][5] and new Object[2][nonConLen].
401 // Also handle the degenerate 1-dimensional case of anewarray.
402 Node* Parse::expand_multianewarray(ciArrayKlass* array_klass, Node* *lengths, int ndimensions, int nargs) {
403 Node* length = lengths[0];
404 assert(length != NULL, "");
405 Node* array = new_array(makecon(TypeKlassPtr::make(array_klass)), length, nargs);
406 if (ndimensions > 1) {
407 jint length_con = find_int_con(length, -1);
408 guarantee(length_con >= 0, "non-constant multianewarray");
409 ciArrayKlass* array_klass_1 = array_klass->as_obj_array_klass()->element_klass()->as_array_klass();
410 const TypePtr* adr_type = TypeAryPtr::OOPS;
411 const TypeOopPtr* elemtype = _gvn.type(array)->is_aryptr()->elem()->make_oopptr();
412 const intptr_t header = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
413 for (jint i = 0; i < length_con; i++) {
414 Node* elem = expand_multianewarray(array_klass_1, &lengths[1], ndimensions-1, nargs);
415 intptr_t offset = header + ((intptr_t)i << LogBytesPerHeapOop);
416 Node* eaddr = basic_plus_adr(array, offset);
417 store_oop_to_array(control(), array, eaddr, adr_type, elem, elemtype, T_OBJECT);
418 }
419 }
420 return array;
421 }
422
423 void Parse::do_multianewarray() {
424 int ndimensions = iter().get_dimensions();
425
426 // the m-dimensional array
427 bool will_link;
428 ciArrayKlass* array_klass = iter().get_klass(will_link)->as_array_klass();
429 assert(will_link, "multianewarray: typeflow responsibility");
430
431 // Note: Array classes are always initialized; no is_initialized check.
432
433 kill_dead_locals();
434
435 // get the lengths from the stack (first dimension is on top)
436 Node** length = NEW_RESOURCE_ARRAY(Node*, ndimensions + 1);
437 length[ndimensions] = NULL; // terminating null for make_runtime_call
438 int j;
439 for (j = ndimensions-1; j >= 0 ; j--) length[j] = pop();
440
441 // The original expression was of this form: new T[length0][length1]...
442 // It is often the case that the lengths are small (except the last).
443 // If that happens, use the fast 1-d creator a constant number of times.
444 const jint expand_limit = MIN2((juint)MultiArrayExpandLimit, (juint)100);
445 jint expand_count = 1; // count of allocations in the expansion
446 jint expand_fanout = 1; // running total fanout
447 for (j = 0; j < ndimensions-1; j++) {
448 jint dim_con = find_int_con(length[j], -1);
449 expand_fanout *= dim_con;
450 expand_count += expand_fanout; // count the level-J sub-arrays
451 if (dim_con <= 0
452 || dim_con > expand_limit
453 || expand_count > expand_limit) {
454 expand_count = 0;
455 break;
456 }
457 }
458
459 // Can use multianewarray instead of [a]newarray if only one dimension,
460 // or if all non-final dimensions are small constants.
461 if (ndimensions == 1 || (1 <= expand_count && expand_count <= expand_limit)) {
462 Node* obj = NULL;
463 // Set the original stack and the reexecute bit for the interpreter
464 // to reexecute the multianewarray bytecode if deoptimization happens.
465 // Do it unconditionally even for one dimension multianewarray.
466 // Note: the reexecute bit will be set in GraphKit::add_safepoint_edges()
467 // when AllocateArray node for newarray is created.
468 { PreserveReexecuteState preexecs(this);
469 inc_sp(ndimensions);
470 // Pass 0 as nargs since uncommon trap code does not need to restore stack.
471 obj = expand_multianewarray(array_klass, &length[0], ndimensions, 0);
472 } //original reexecute and sp are set back here
473 push(obj);
474 return;
475 }
476
477 address fun = NULL;
478 switch (ndimensions) {
479 case 1: ShouldNotReachHere(); break;
480 case 2: fun = OptoRuntime::multianewarray2_Java(); break;
481 case 3: fun = OptoRuntime::multianewarray3_Java(); break;
482 case 4: fun = OptoRuntime::multianewarray4_Java(); break;
483 case 5: fun = OptoRuntime::multianewarray5_Java(); break;
484 };
485 Node* c = NULL;
486
487 if (fun != NULL) {
488 c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
489 OptoRuntime::multianewarray_Type(ndimensions),
490 fun, NULL, TypeRawPtr::BOTTOM,
491 makecon(TypeKlassPtr::make(array_klass)),
492 length[0], length[1], length[2],
493 (ndimensions > 2) ? length[3] : NULL,
494 (ndimensions > 3) ? length[4] : NULL);
495 } else {
496 // Create a java array for dimension sizes
497 Node* dims = NULL;
498 { PreserveReexecuteState preexecs(this);
499 inc_sp(ndimensions);
500 Node* dims_array_klass = makecon(TypeKlassPtr::make(ciArrayKlass::make(ciType::make(T_INT))));
501 dims = new_array(dims_array_klass, intcon(ndimensions), 0);
502
503 // Fill-in it with values
504 for (j = 0; j < ndimensions; j++) {
505 Node *dims_elem = array_element_address(dims, intcon(j), T_INT);
506 store_to_memory(control(), dims_elem, length[j], T_INT, TypeAryPtr::INTS);
507 }
508 }
509
510 c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
511 OptoRuntime::multianewarrayN_Type(),
512 OptoRuntime::multianewarrayN_Java(), NULL, TypeRawPtr::BOTTOM,
513 makecon(TypeKlassPtr::make(array_klass)),
514 dims);
515 }
516 make_slow_call_ex(c, env()->Throwable_klass(), false);
517
518 Node* res = _gvn.transform(new (C) ProjNode(c, TypeFunc::Parms));
519
520 const Type* type = TypeOopPtr::make_from_klass_raw(array_klass);
521
522 // Improve the type: We know it's not null, exact, and of a given length.
523 type = type->is_ptr()->cast_to_ptr_type(TypePtr::NotNull);
524 type = type->is_aryptr()->cast_to_exactness(true);
525
526 const TypeInt* ltype = _gvn.find_int_type(length[0]);
527 if (ltype != NULL)
528 type = type->is_aryptr()->cast_to_size(ltype);
529
530 // We cannot sharpen the nested sub-arrays, since the top level is mutable.
531
532 Node* cast = _gvn.transform( new (C) CheckCastPPNode(control(), res, type) );
533 push(cast);
534
535 // Possible improvements:
536 // - Make a fast path for small multi-arrays. (W/ implicit init. loops.)
537 // - Issue CastII against length[*] values, to TypeInt::POS.
538 }