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/castnode.hpp"
32 #include "opto/memnode.hpp"
33 #include "opto/parse.hpp"
34 #include "opto/rootnode.hpp"
35 #include "opto/runtime.hpp"
36 #include "opto/subnode.hpp"
37 #include "runtime/deoptimization.hpp"
38 #include "runtime/handles.inline.hpp"
39
40 //=============================================================================
41 // Helper methods for _get* and _put* bytecodes
42 //=============================================================================
43 bool Parse::static_field_ok_in_clinit(ciField *field, ciMethod *method) {
44 // Could be the field_holder's <clinit> method, or <clinit> for a subklass.
45 // Better to check now than to Deoptimize as soon as we execute
46 assert( field->is_static(), "Only check if field is static");
47 // is_being_initialized() is too generous. It allows access to statics
48 // by threads that are not running the <clinit> before the <clinit> finishes.
49 // return field->holder()->is_being_initialized();
50
51 // The following restriction is correct but conservative.
52 // It is also desirable to allow compilation of methods called from <clinit>
53 // but this generated code will need to be made safe for execution by
54 // other threads, or the transition from interpreted to compiled code would
55 // need to be guarded.
56 ciInstanceKlass *field_holder = field->holder();
57
58 bool access_OK = false;
59 if (method->holder()->is_subclass_of(field_holder)) {
60 if (method->is_static()) {
61 if (method->name() == ciSymbol::class_initializer_name()) {
62 // OK to access static fields inside initializer
63 access_OK = true;
64 }
65 } else {
66 if (method->name() == ciSymbol::object_initializer_name()) {
67 // It's also OK to access static fields inside a constructor,
68 // because any thread calling the constructor must first have
69 // synchronized on the class by executing a '_new' bytecode.
70 access_OK = true;
71 }
72 }
73 }
74
75 return access_OK;
76
77 }
78
79
80 void Parse::do_field_access(bool is_get, bool is_field) {
81 bool will_link;
82 ciField* field = iter().get_field(will_link);
83 assert(will_link, "getfield: typeflow responsibility");
84
85 ciInstanceKlass* field_holder = field->holder();
86
87 if (is_field == field->is_static()) {
88 // Interpreter will throw java_lang_IncompatibleClassChangeError
89 // Check this before allowing <clinit> methods to access static fields
90 uncommon_trap(Deoptimization::Reason_unhandled,
91 Deoptimization::Action_none);
92 return;
93 }
94
95 if (!is_field && !field_holder->is_initialized()) {
96 if (!static_field_ok_in_clinit(field, method())) {
97 uncommon_trap(Deoptimization::Reason_uninitialized,
98 Deoptimization::Action_reinterpret,
99 NULL, "!static_field_ok_in_clinit");
100 return;
101 }
102 }
103
104 // Deoptimize on putfield writes to call site target field.
105 if (!is_get && field->is_call_site_target()) {
106 uncommon_trap(Deoptimization::Reason_unhandled,
107 Deoptimization::Action_reinterpret,
108 NULL, "put to call site target field");
109 return;
110 }
111
112 assert(field->will_link(method()->holder(), bc()), "getfield: typeflow responsibility");
113
114 // Note: We do not check for an unloaded field type here any more.
115
116 // Generate code for the object pointer.
117 Node* obj;
118 if (is_field) {
119 int obj_depth = is_get ? 0 : field->type()->size();
120 obj = null_check(peek(obj_depth));
121 // Compile-time detect of null-exception?
122 if (stopped()) return;
123
124 #ifdef ASSERT
125 const TypeInstPtr *tjp = TypeInstPtr::make(TypePtr::NotNull, iter().get_declared_field_holder());
126 assert(_gvn.type(obj)->higher_equal(tjp), "cast_up is no longer needed");
127 #endif
128
129 if (is_get) {
130 (void) pop(); // pop receiver before getting
131 do_get_xxx(obj, field, is_field);
132 } else {
133 do_put_xxx(obj, field, is_field);
134 (void) pop(); // pop receiver after putting
135 }
136 } else {
137 const TypeInstPtr* tip = TypeInstPtr::make(field_holder->java_mirror());
138 obj = _gvn.makecon(tip);
139 if (is_get) {
140 do_get_xxx(obj, field, is_field);
141 } else {
142 do_put_xxx(obj, field, is_field);
143 }
144 }
145 }
146
147
148 void Parse::do_get_xxx(Node* obj, ciField* field, bool is_field) {
149 // Does this field have a constant value? If so, just push the value.
150 if (field->is_constant()) {
151 // final or stable field
152 const Type* stable_type = NULL;
153 if (FoldStableValues && field->is_stable()) {
154 stable_type = Type::get_const_type(field->type());
155 if (field->type()->is_array_klass()) {
156 int stable_dimension = field->type()->as_array_klass()->dimension();
157 stable_type = stable_type->is_aryptr()->cast_to_stable(true, stable_dimension);
158 }
159 }
160 if (field->is_static()) {
161 // final static field
162 if (C->eliminate_boxing()) {
163 // The pointers in the autobox arrays are always non-null.
164 ciSymbol* klass_name = field->holder()->name();
165 if (field->name() == ciSymbol::cache_field_name() &&
166 field->holder()->uses_default_loader() &&
167 (klass_name == ciSymbol::java_lang_Character_CharacterCache() ||
168 klass_name == ciSymbol::java_lang_Byte_ByteCache() ||
169 klass_name == ciSymbol::java_lang_Short_ShortCache() ||
170 klass_name == ciSymbol::java_lang_Integer_IntegerCache() ||
171 klass_name == ciSymbol::java_lang_Long_LongCache())) {
172 bool require_const = true;
173 bool autobox_cache = true;
174 if (push_constant(field->constant_value(), require_const, autobox_cache)) {
175 return;
176 }
177 }
178 }
179 if (push_constant(field->constant_value(), false, false, stable_type))
180 return;
181 } else {
182 // final or stable non-static field
183 // Treat final non-static fields of trusted classes (classes in
184 // java.lang.invoke and sun.invoke packages and subpackages) as
185 // compile time constants.
186 if (obj->is_Con()) {
187 const TypeOopPtr* oop_ptr = obj->bottom_type()->isa_oopptr();
188 ciObject* constant_oop = oop_ptr->const_oop();
189 ciConstant constant = field->constant_value_of(constant_oop);
190 if (FoldStableValues && field->is_stable() && constant.is_null_or_zero()) {
191 // fall through to field load; the field is not yet initialized
192 } else {
193 if (push_constant(constant, true, false, stable_type))
194 return;
195 }
196 }
197 }
198 }
199
200 ciType* field_klass = field->type();
201 bool is_vol = field->is_volatile();
202
203 // Compute address and memory type.
204 int offset = field->offset_in_bytes();
205 const TypePtr* adr_type = C->alias_type(field)->adr_type();
206 Node *adr = basic_plus_adr(obj, obj, offset);
207 BasicType bt = field->layout_type();
208
209 // Build the resultant type of the load
210 const Type *type;
211
212 bool must_assert_null = false;
213
214 if( bt == T_OBJECT ) {
215 if (!field->type()->is_loaded()) {
216 type = TypeInstPtr::BOTTOM;
217 must_assert_null = true;
218 } else if (field->is_constant() && field->is_static()) {
219 // This can happen if the constant oop is non-perm.
220 ciObject* con = field->constant_value().as_object();
221 // Do not "join" in the previous type; it doesn't add value,
222 // and may yield a vacuous result if the field is of interface type.
223 type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
224 assert(type != NULL, "field singleton type must be consistent");
225 } else {
226 type = TypeOopPtr::make_from_klass(field_klass->as_klass());
227 }
228 } else {
229 type = Type::get_const_basic_type(bt);
230 }
231 if (support_IRIW_for_not_multiple_copy_atomic_cpu && field->is_volatile()) {
232 insert_mem_bar(Op_MemBarVolatile); // StoreLoad barrier
233 }
234 // Build the load.
235 //
236 MemNode::MemOrd mo = is_vol ? MemNode::acquire : MemNode::unordered;
237 bool needs_atomic_access = is_vol || AlwaysAtomicAccesses;
238 Node* ld = make_load(NULL, adr, type, bt, adr_type, mo, needs_atomic_access);
239
240 // Adjust Java stack
241 if (type2size[bt] == 1)
242 push(ld);
243 else
244 push_pair(ld);
245
246 if (must_assert_null) {
247 // Do not take a trap here. It's possible that the program
248 // will never load the field's class, and will happily see
249 // null values in this field forever. Don't stumble into a
250 // trap for such a program, or we might get a long series
251 // of useless recompilations. (Or, we might load a class
252 // which should not be loaded.) If we ever see a non-null
253 // value, we will then trap and recompile. (The trap will
254 // not need to mention the class index, since the class will
255 // already have been loaded if we ever see a non-null value.)
256 // uncommon_trap(iter().get_field_signature_index());
257 #ifndef PRODUCT
258 if (PrintOpto && (Verbose || WizardMode)) {
259 method()->print_name(); tty->print_cr(" asserting nullness of field at bci: %d", bci());
260 }
261 #endif
262 if (C->log() != NULL) {
263 C->log()->elem("assert_null reason='field' klass='%d'",
264 C->log()->identify(field->type()));
265 }
266 // If there is going to be a trap, put it at the next bytecode:
267 set_bci(iter().next_bci());
268 null_assert(peek());
269 set_bci(iter().cur_bci()); // put it back
270 }
271
272 // If reference is volatile, prevent following memory ops from
273 // floating up past the volatile read. Also prevents commoning
274 // another volatile read.
275 if (field->is_volatile()) {
276 // Memory barrier includes bogus read of value to force load BEFORE membar
277 insert_mem_bar(Op_MemBarAcquire, ld);
278 }
279 }
280
281 void Parse::do_put_xxx(Node* obj, ciField* field, bool is_field) {
282 bool is_vol = field->is_volatile();
283 // If reference is volatile, prevent following memory ops from
284 // floating down past the volatile write. Also prevents commoning
285 // another volatile read.
286 // AArch64 uses store release (which does everything we need to keep
287 // the machine in order) but we still need a compiler barrier here.
288 if (is_vol) {
289 insert_mem_bar(NOT_AARCH64(Op_MemBarRelease) AARCH64_ONLY(Op_MemBarCPUOrder));
290 }
291
292 // Compute address and memory type.
293 int offset = field->offset_in_bytes();
294 const TypePtr* adr_type = C->alias_type(field)->adr_type();
295 Node* adr = basic_plus_adr(obj, obj, offset);
296 BasicType bt = field->layout_type();
297 // Value to be stored
298 Node* val = type2size[bt] == 1 ? pop() : pop_pair();
299 // Round doubles before storing
300 if (bt == T_DOUBLE) val = dstore_rounding(val);
301
302 // Conservatively release stores of object references.
303 const MemNode::MemOrd mo =
304 is_vol ?
305 // Volatile fields need releasing stores.
306 MemNode::release :
307 // Non-volatile fields also need releasing stores if they hold an
308 // object reference, because the object reference might point to
309 // a freshly created object.
310 StoreNode::release_if_reference(bt);
311
312 // Store the value.
313 Node* store;
314 if (bt == T_OBJECT) {
315 const TypeOopPtr* field_type;
316 if (!field->type()->is_loaded()) {
317 field_type = TypeInstPtr::BOTTOM;
318 } else {
319 field_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
320 }
321 store = store_oop_to_object(control(), obj, adr, adr_type, val, field_type, bt, mo);
322 } else {
323 bool needs_atomic_access = is_vol || AlwaysAtomicAccesses;
324 store = store_to_memory(control(), adr, val, bt, adr_type, mo, needs_atomic_access);
325 }
326
327 // If reference is volatile, prevent following volatiles ops from
328 // floating up before the volatile write.
329 if (is_vol) {
330 // If not multiple copy atomic, we do the MemBarVolatile before the load.
331 if (!support_IRIW_for_not_multiple_copy_atomic_cpu) {
332 insert_mem_bar(NOT_AARCH64(Op_MemBarVolatile) AARCH64_ONLY(Op_MemBarCPUOrder)); // Use fat membar
333 }
334 // Remember we wrote a volatile field.
335 // For not multiple copy atomic cpu (ppc64) a barrier should be issued
336 // in constructors which have such stores. See do_exits() in parse1.cpp.
337 if (is_field) {
338 set_wrote_volatile(true);
339 }
340 }
341
342 if (is_field) {
343 set_wrote_fields(true);
344 }
345
346 // If the field is final, the rules of Java say we are in <init> or <clinit>.
347 // Note the presence of writes to final non-static fields, so that we
348 // can insert a memory barrier later on to keep the writes from floating
349 // out of the constructor.
350 // Any method can write a @Stable field; insert memory barriers after those also.
351 if (is_field && (field->is_final() || field->is_stable())) {
352 if (field->is_final()) {
353 set_wrote_final(true);
354 }
355 if (field->is_stable()) {
356 set_wrote_stable(true);
357 }
358
359 // Preserve allocation ptr to create precedent edge to it in membar
360 // generated on exit from constructor.
361 if (C->eliminate_boxing() &&
362 adr_type->isa_oopptr() && adr_type->is_oopptr()->is_ptr_to_boxed_value() &&
363 AllocateNode::Ideal_allocation(obj, &_gvn) != NULL) {
364 set_alloc_with_final(obj);
365 }
366 }
367 }
368
369
370
371 bool Parse::push_constant(ciConstant constant, bool require_constant, bool is_autobox_cache, const Type* stable_type) {
372 const Type* con_type = Type::make_from_constant(constant, require_constant, is_autobox_cache);
373 switch (constant.basic_type()) {
374 case T_ARRAY:
375 case T_OBJECT:
376 // cases:
377 // can_be_constant = (oop not scavengable || ScavengeRootsInCode != 0)
378 // should_be_constant = (oop not scavengable || ScavengeRootsInCode >= 2)
379 // An oop is not scavengable if it is in the perm gen.
380 if (stable_type != NULL && con_type != NULL && con_type->isa_oopptr())
381 con_type = con_type->join_speculative(stable_type);
382 break;
383
384 case T_ILLEGAL:
385 // Invalid ciConstant returned due to OutOfMemoryError in the CI
386 assert(C->env()->failing(), "otherwise should not see this");
387 // These always occur because of object types; we are going to
388 // bail out anyway, so make the stack depths match up
389 push( zerocon(T_OBJECT) );
390 return false;
391 }
392
393 if (con_type == NULL)
394 // we cannot inline the oop, but we can use it later to narrow a type
395 return false;
396
397 push_node(constant.basic_type(), makecon(con_type));
398 return true;
399 }
400
401
402 //=============================================================================
403 void Parse::do_anewarray() {
404 bool will_link;
405 ciKlass* klass = iter().get_klass(will_link);
406
407 // Uncommon Trap when class that array contains is not loaded
408 // we need the loaded class for the rest of graph; do not
409 // initialize the container class (see Java spec)!!!
410 assert(will_link, "anewarray: typeflow responsibility");
411
412 ciObjArrayKlass* array_klass = ciObjArrayKlass::make(klass);
413 // Check that array_klass object is loaded
414 if (!array_klass->is_loaded()) {
415 // Generate uncommon_trap for unloaded array_class
416 uncommon_trap(Deoptimization::Reason_unloaded,
417 Deoptimization::Action_reinterpret,
418 array_klass);
419 return;
420 }
421
422 kill_dead_locals();
423
424 const TypeKlassPtr* array_klass_type = TypeKlassPtr::make(array_klass);
425 Node* count_val = pop();
426 Node* obj = new_array(makecon(array_klass_type), count_val, 1);
427 push(obj);
428 }
429
430
431 void Parse::do_newarray(BasicType elem_type) {
432 kill_dead_locals();
433
434 Node* count_val = pop();
435 const TypeKlassPtr* array_klass = TypeKlassPtr::make(ciTypeArrayKlass::make(elem_type));
436 Node* obj = new_array(makecon(array_klass), count_val, 1);
437 // Push resultant oop onto stack
438 push(obj);
439 }
440
441 // Expand simple expressions like new int[3][5] and new Object[2][nonConLen].
442 // Also handle the degenerate 1-dimensional case of anewarray.
443 Node* Parse::expand_multianewarray(ciArrayKlass* array_klass, Node* *lengths, int ndimensions, int nargs) {
444 Node* length = lengths[0];
445 assert(length != NULL, "");
446 Node* array = new_array(makecon(TypeKlassPtr::make(array_klass)), length, nargs);
447 if (ndimensions > 1) {
448 jint length_con = find_int_con(length, -1);
449 guarantee(length_con >= 0, "non-constant multianewarray");
450 ciArrayKlass* array_klass_1 = array_klass->as_obj_array_klass()->element_klass()->as_array_klass();
451 const TypePtr* adr_type = TypeAryPtr::OOPS;
452 const TypeOopPtr* elemtype = _gvn.type(array)->is_aryptr()->elem()->make_oopptr();
453 const intptr_t header = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
454 for (jint i = 0; i < length_con; i++) {
455 Node* elem = expand_multianewarray(array_klass_1, &lengths[1], ndimensions-1, nargs);
456 intptr_t offset = header + ((intptr_t)i << LogBytesPerHeapOop);
457 Node* eaddr = basic_plus_adr(array, offset);
458 store_oop_to_array(control(), array, eaddr, adr_type, elem, elemtype, T_OBJECT, MemNode::unordered);
459 }
460 }
461 return array;
462 }
463
464 void Parse::do_multianewarray() {
465 int ndimensions = iter().get_dimensions();
466
467 // the m-dimensional array
468 bool will_link;
469 ciArrayKlass* array_klass = iter().get_klass(will_link)->as_array_klass();
470 assert(will_link, "multianewarray: typeflow responsibility");
471
472 // Note: Array classes are always initialized; no is_initialized check.
473
474 kill_dead_locals();
475
476 // get the lengths from the stack (first dimension is on top)
477 Node** length = NEW_RESOURCE_ARRAY(Node*, ndimensions + 1);
478 length[ndimensions] = NULL; // terminating null for make_runtime_call
479 int j;
480 for (j = ndimensions-1; j >= 0 ; j--) length[j] = pop();
481
482 // The original expression was of this form: new T[length0][length1]...
483 // It is often the case that the lengths are small (except the last).
484 // If that happens, use the fast 1-d creator a constant number of times.
485 const jint expand_limit = MIN2((juint)MultiArrayExpandLimit, (juint)100);
486 jint expand_count = 1; // count of allocations in the expansion
487 jint expand_fanout = 1; // running total fanout
488 for (j = 0; j < ndimensions-1; j++) {
489 jint dim_con = find_int_con(length[j], -1);
490 expand_fanout *= dim_con;
491 expand_count += expand_fanout; // count the level-J sub-arrays
492 if (dim_con <= 0
493 || dim_con > expand_limit
494 || expand_count > expand_limit) {
495 expand_count = 0;
496 break;
497 }
498 }
499
500 // Can use multianewarray instead of [a]newarray if only one dimension,
501 // or if all non-final dimensions are small constants.
502 if (ndimensions == 1 || (1 <= expand_count && expand_count <= expand_limit)) {
503 Node* obj = NULL;
504 // Set the original stack and the reexecute bit for the interpreter
505 // to reexecute the multianewarray bytecode if deoptimization happens.
506 // Do it unconditionally even for one dimension multianewarray.
507 // Note: the reexecute bit will be set in GraphKit::add_safepoint_edges()
508 // when AllocateArray node for newarray is created.
509 { PreserveReexecuteState preexecs(this);
510 inc_sp(ndimensions);
511 // Pass 0 as nargs since uncommon trap code does not need to restore stack.
512 obj = expand_multianewarray(array_klass, &length[0], ndimensions, 0);
513 } //original reexecute and sp are set back here
514 push(obj);
515 return;
516 }
517
518 address fun = NULL;
519 switch (ndimensions) {
520 case 1: ShouldNotReachHere(); break;
521 case 2: fun = OptoRuntime::multianewarray2_Java(); break;
522 case 3: fun = OptoRuntime::multianewarray3_Java(); break;
523 case 4: fun = OptoRuntime::multianewarray4_Java(); break;
524 case 5: fun = OptoRuntime::multianewarray5_Java(); break;
525 };
526 Node* c = NULL;
527
528 if (fun != NULL) {
529 c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
530 OptoRuntime::multianewarray_Type(ndimensions),
531 fun, NULL, TypeRawPtr::BOTTOM,
532 makecon(TypeKlassPtr::make(array_klass)),
533 length[0], length[1], length[2],
534 (ndimensions > 2) ? length[3] : NULL,
535 (ndimensions > 3) ? length[4] : NULL);
536 } else {
537 // Create a java array for dimension sizes
538 Node* dims = NULL;
539 { PreserveReexecuteState preexecs(this);
540 inc_sp(ndimensions);
541 Node* dims_array_klass = makecon(TypeKlassPtr::make(ciArrayKlass::make(ciType::make(T_INT))));
542 dims = new_array(dims_array_klass, intcon(ndimensions), 0);
543
544 // Fill-in it with values
545 for (j = 0; j < ndimensions; j++) {
546 Node *dims_elem = array_element_address(dims, intcon(j), T_INT);
547 store_to_memory(control(), dims_elem, length[j], T_INT, TypeAryPtr::INTS, MemNode::unordered);
548 }
549 }
550
551 c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
552 OptoRuntime::multianewarrayN_Type(),
553 OptoRuntime::multianewarrayN_Java(), NULL, TypeRawPtr::BOTTOM,
554 makecon(TypeKlassPtr::make(array_klass)),
555 dims);
556 }
557 make_slow_call_ex(c, env()->Throwable_klass(), false);
558
559 Node* res = _gvn.transform(new ProjNode(c, TypeFunc::Parms));
560
561 const Type* type = TypeOopPtr::make_from_klass_raw(array_klass);
562
563 // Improve the type: We know it's not null, exact, and of a given length.
564 type = type->is_ptr()->cast_to_ptr_type(TypePtr::NotNull);
565 type = type->is_aryptr()->cast_to_exactness(true);
566
567 const TypeInt* ltype = _gvn.find_int_type(length[0]);
568 if (ltype != NULL)
569 type = type->is_aryptr()->cast_to_size(ltype);
570
571 // We cannot sharpen the nested sub-arrays, since the top level is mutable.
572
573 Node* cast = _gvn.transform( new CheckCastPPNode(control(), res, type) );
574 push(cast);
575
576 // Possible improvements:
577 // - Make a fast path for small multi-arrays. (W/ implicit init. loops.)
578 // - Issue CastII against length[*] values, to TypeInt::POS.
579 }