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 #if INCLUDE_ALL_GCS
40 #include "gc_implementation/shenandoah/c2/shenandoahBarrierSetC2.hpp"
41 #endif
42
43 //=============================================================================
44 // Helper methods for _get* and _put* bytecodes
45 //=============================================================================
46 bool Parse::static_field_ok_in_clinit(ciField *field, ciMethod *method) {
47 // Could be the field_holder's <clinit> method, or <clinit> for a subklass.
48 // Better to check now than to Deoptimize as soon as we execute
49 assert( field->is_static(), "Only check if field is static");
50 // is_being_initialized() is too generous. It allows access to statics
51 // by threads that are not running the <clinit> before the <clinit> finishes.
52 // return field->holder()->is_being_initialized();
53
54 // The following restriction is correct but conservative.
55 // It is also desirable to allow compilation of methods called from <clinit>
56 // but this generated code will need to be made safe for execution by
57 // other threads, or the transition from interpreted to compiled code would
58 // need to be guarded.
59 ciInstanceKlass *field_holder = field->holder();
60
61 bool access_OK = false;
62 if (method->holder()->is_subclass_of(field_holder)) {
63 if (method->is_static()) {
64 if (method->name() == ciSymbol::class_initializer_name()) {
65 // OK to access static fields inside initializer
66 access_OK = true;
67 }
68 } else {
69 if (method->name() == ciSymbol::object_initializer_name()) {
70 // It's also OK to access static fields inside a constructor,
71 // because any thread calling the constructor must first have
72 // synchronized on the class by executing a '_new' bytecode.
73 access_OK = true;
74 }
75 }
76 }
77
78 return access_OK;
79
80 }
81
82
83 void Parse::do_field_access(bool is_get, bool is_field) {
84 bool will_link;
85 ciField* field = iter().get_field(will_link);
86 assert(will_link, "getfield: typeflow responsibility");
87
88 ciInstanceKlass* field_holder = field->holder();
89
90 if (is_field == field->is_static()) {
91 // Interpreter will throw java_lang_IncompatibleClassChangeError
92 // Check this before allowing <clinit> methods to access static fields
93 uncommon_trap(Deoptimization::Reason_unhandled,
94 Deoptimization::Action_none);
95 return;
96 }
97
98 if (!is_field && !field_holder->is_initialized()) {
99 if (!static_field_ok_in_clinit(field, method())) {
100 uncommon_trap(Deoptimization::Reason_uninitialized,
101 Deoptimization::Action_reinterpret,
102 NULL, "!static_field_ok_in_clinit");
103 return;
104 }
105 }
106
107 // Deoptimize on putfield writes to call site target field.
108 if (!is_get && field->is_call_site_target()) {
109 uncommon_trap(Deoptimization::Reason_unhandled,
110 Deoptimization::Action_reinterpret,
111 NULL, "put to call site target field");
112 return;
113 }
114
115 assert(field->will_link(method()->holder(), bc()), "getfield: typeflow responsibility");
116
117 // Note: We do not check for an unloaded field type here any more.
118
119 // Generate code for the object pointer.
120 Node* obj;
121 if (is_field) {
122 int obj_depth = is_get ? 0 : field->type()->size();
123 obj = null_check(peek(obj_depth));
124 // Compile-time detect of null-exception?
125 if (stopped()) return;
126
127 #ifdef ASSERT
128 const TypeInstPtr *tjp = TypeInstPtr::make(TypePtr::NotNull, iter().get_declared_field_holder());
129 assert(_gvn.type(obj)->higher_equal(tjp), "cast_up is no longer needed");
130 #endif
131
132 if (is_get) {
133 (void) pop(); // pop receiver before getting
134 do_get_xxx(obj, field, is_field);
135 } else {
136 do_put_xxx(obj, field, is_field);
137 (void) pop(); // pop receiver after putting
138 }
139 } else {
140 const TypeInstPtr* tip = TypeInstPtr::make(field_holder->java_mirror());
141 obj = _gvn.makecon(tip);
142 if (is_get) {
143 do_get_xxx(obj, field, is_field);
144 } else {
145 do_put_xxx(obj, field, is_field);
146 }
147 }
148 }
149
150
151 void Parse::do_get_xxx(Node* obj, ciField* field, bool is_field) {
152 // Does this field have a constant value? If so, just push the value.
153 if (field->is_constant()) {
154 // final or stable field
155 const Type* stable_type = NULL;
156 if (FoldStableValues && field->is_stable()) {
157 stable_type = Type::get_const_type(field->type());
158 if (field->type()->is_array_klass()) {
159 int stable_dimension = field->type()->as_array_klass()->dimension();
160 stable_type = stable_type->is_aryptr()->cast_to_stable(true, stable_dimension);
161 }
162 }
163 if (field->is_static()) {
164 // final static field
165 if (C->eliminate_boxing()) {
166 // The pointers in the autobox arrays are always non-null.
167 ciSymbol* klass_name = field->holder()->name();
168 if (field->name() == ciSymbol::cache_field_name() &&
169 field->holder()->uses_default_loader() &&
170 (klass_name == ciSymbol::java_lang_Character_CharacterCache() ||
171 klass_name == ciSymbol::java_lang_Byte_ByteCache() ||
172 klass_name == ciSymbol::java_lang_Short_ShortCache() ||
173 klass_name == ciSymbol::java_lang_Integer_IntegerCache() ||
174 klass_name == ciSymbol::java_lang_Long_LongCache())) {
175 bool require_const = true;
176 bool autobox_cache = true;
177 if (push_constant(field->constant_value(), require_const, autobox_cache)) {
178 return;
179 }
180 }
181 }
182 if (push_constant(field->constant_value(), false, false, stable_type))
183 return;
184 } else {
185 // final or stable non-static field
186 // Treat final non-static fields of trusted classes (classes in
187 // java.lang.invoke and sun.invoke packages and subpackages) as
188 // compile time constants.
189 if (obj->is_Con()) {
190 const TypeOopPtr* oop_ptr = obj->bottom_type()->isa_oopptr();
191 ciObject* constant_oop = oop_ptr->const_oop();
192 ciConstant constant = field->constant_value_of(constant_oop);
193 if (FoldStableValues && field->is_stable() && constant.is_null_or_zero()) {
194 // fall through to field load; the field is not yet initialized
195 } else {
196 if (push_constant(constant, true, false, stable_type))
197 return;
198 }
199 }
200 }
201 }
202
203 Node* leading_membar = NULL;
204 ciType* field_klass = field->type();
205 bool is_vol = field->is_volatile();
206
207 // Compute address and memory type.
208 int offset = field->offset_in_bytes();
209 const TypePtr* adr_type = C->alias_type(field)->adr_type();
210 Node *adr = basic_plus_adr(obj, obj, offset);
211 BasicType bt = field->layout_type();
212
213 // Build the resultant type of the load
214 const Type *type;
215
216 bool must_assert_null = false;
217
218 if( bt == T_OBJECT ) {
219 if (!field->type()->is_loaded()) {
220 type = TypeInstPtr::BOTTOM;
221 must_assert_null = true;
222 } else if (field->is_constant() && field->is_static()) {
223 // This can happen if the constant oop is non-perm.
224 ciObject* con = field->constant_value().as_object();
225 // Do not "join" in the previous type; it doesn't add value,
226 // and may yield a vacuous result if the field is of interface type.
227 type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
228 assert(type != NULL, "field singleton type must be consistent");
229 } else {
230 type = TypeOopPtr::make_from_klass(field_klass->as_klass());
231 }
232 } else {
233 type = Type::get_const_basic_type(bt);
234 }
235 if (support_IRIW_for_not_multiple_copy_atomic_cpu && field->is_volatile()) {
236 leading_membar = insert_mem_bar(Op_MemBarVolatile); // StoreLoad barrier
237 }
238 // Build the load.
239 //
240 MemNode::MemOrd mo = is_vol ? MemNode::acquire : MemNode::unordered;
241 Node* ld = make_load(NULL, adr, type, bt, adr_type, mo, LoadNode::DependsOnlyOnTest, is_vol);
242
243 Node* load = ld;
244 #if INCLUDE_ALL_GCS
245 if (UseShenandoahGC && (bt == T_OBJECT || bt == T_ARRAY)) {
246 ld = ShenandoahBarrierSetC2::bsc2()->load_reference_barrier(this, ld);
247 }
248 #endif
249
250 // Adjust Java stack
251 if (type2size[bt] == 1)
252 push(ld);
253 else
254 push_pair(ld);
255
256 if (must_assert_null) {
257 // Do not take a trap here. It's possible that the program
258 // will never load the field's class, and will happily see
259 // null values in this field forever. Don't stumble into a
260 // trap for such a program, or we might get a long series
261 // of useless recompilations. (Or, we might load a class
262 // which should not be loaded.) If we ever see a non-null
263 // value, we will then trap and recompile. (The trap will
264 // not need to mention the class index, since the class will
265 // already have been loaded if we ever see a non-null value.)
266 // uncommon_trap(iter().get_field_signature_index());
267 #ifndef PRODUCT
268 if (PrintOpto && (Verbose || WizardMode)) {
269 method()->print_name(); tty->print_cr(" asserting nullness of field at bci: %d", bci());
270 }
271 #endif
272 if (C->log() != NULL) {
273 C->log()->elem("assert_null reason='field' klass='%d'",
274 C->log()->identify(field->type()));
275 }
276 // If there is going to be a trap, put it at the next bytecode:
277 set_bci(iter().next_bci());
278 null_assert(peek());
279 set_bci(iter().cur_bci()); // put it back
280 }
281
282 // If reference is volatile, prevent following memory ops from
283 // floating up past the volatile read. Also prevents commoning
284 // another volatile read.
285 if (field->is_volatile()) {
286 // Memory barrier includes bogus read of value to force load BEFORE membar
287 assert(leading_membar == NULL || support_IRIW_for_not_multiple_copy_atomic_cpu, "no leading membar expected");
288 Node* mb = insert_mem_bar(Op_MemBarAcquire, load);
289 mb->as_MemBar()->set_trailing_load();
290 }
291 }
292
293 void Parse::do_put_xxx(Node* obj, ciField* field, bool is_field) {
294 Node* leading_membar = NULL;
295 bool is_vol = field->is_volatile();
296 // If reference is volatile, prevent following memory ops from
297 // floating down past the volatile write. Also prevents commoning
298 // another volatile read.
299 if (is_vol) {
300 leading_membar = insert_mem_bar(Op_MemBarRelease);
301 }
302
303 // Compute address and memory type.
304 int offset = field->offset_in_bytes();
305 const TypePtr* adr_type = C->alias_type(field)->adr_type();
306 Node* adr = basic_plus_adr(obj, obj, offset);
307 BasicType bt = field->layout_type();
308 // Value to be stored
309 Node* val = type2size[bt] == 1 ? pop() : pop_pair();
310 // Round doubles before storing
311 if (bt == T_DOUBLE) val = dstore_rounding(val);
312
313 // Conservatively release stores of object references.
314 const MemNode::MemOrd mo =
315 is_vol ?
316 // Volatile fields need releasing stores.
317 MemNode::release :
318 // Non-volatile fields also need releasing stores if they hold an
319 // object reference, because the object reference might point to
320 // a freshly created object.
321 StoreNode::release_if_reference(bt);
322
323 // Store the value.
324 Node* store;
325 if (bt == T_OBJECT) {
326 const TypeOopPtr* field_type;
327 if (!field->type()->is_loaded()) {
328 field_type = TypeInstPtr::BOTTOM;
329 } else {
330 field_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
331 }
332 store = store_oop_to_object(control(), obj, adr, adr_type, val, field_type, bt, mo);
333 } else {
334 store = store_to_memory(control(), adr, val, bt, adr_type, mo, is_vol);
335 }
336
337 // If reference is volatile, prevent following volatiles ops from
338 // floating up before the volatile write.
339 if (is_vol) {
340 // If not multiple copy atomic, we do the MemBarVolatile before the load.
341 if (!support_IRIW_for_not_multiple_copy_atomic_cpu) {
342 Node* mb = insert_mem_bar(Op_MemBarVolatile, store); // Use fat membar
343 MemBarNode::set_store_pair(leading_membar->as_MemBar(), mb->as_MemBar());
344 }
345 // Remember we wrote a volatile field.
346 // For not multiple copy atomic cpu (ppc64) a barrier should be issued
347 // in constructors which have such stores. See do_exits() in parse1.cpp.
348 if (is_field) {
349 set_wrote_volatile(true);
350 }
351 }
352
353 // If the field is final, the rules of Java say we are in <init> or <clinit>.
354 // Note the presence of writes to final non-static fields, so that we
355 // can insert a memory barrier later on to keep the writes from floating
356 // out of the constructor.
357 // Any method can write a @Stable field; insert memory barriers after those also.
358 if (is_field && (field->is_final() || field->is_stable())) {
359 set_wrote_final(true);
360 // Preserve allocation ptr to create precedent edge to it in membar
361 // generated on exit from constructor.
362 if (C->eliminate_boxing() &&
363 adr_type->isa_oopptr() && adr_type->is_oopptr()->is_ptr_to_boxed_value() &&
364 AllocateNode::Ideal_allocation(obj, &_gvn) != NULL) {
365 set_alloc_with_final(obj);
366 }
367 }
368 }
369
370
371
372 bool Parse::push_constant(ciConstant constant, bool require_constant, bool is_autobox_cache, const Type* stable_type) {
373 const Type* con_type = Type::make_from_constant(constant, require_constant, is_autobox_cache);
374 switch (constant.basic_type()) {
375 case T_ARRAY:
376 case T_OBJECT:
377 // cases:
378 // can_be_constant = (oop not scavengable || ScavengeRootsInCode != 0)
379 // should_be_constant = (oop not scavengable || ScavengeRootsInCode >= 2)
380 // An oop is not scavengable if it is in the perm gen.
381 if (stable_type != NULL && con_type != NULL && con_type->isa_oopptr())
382 con_type = con_type->join_speculative(stable_type);
383 break;
384
385 case T_ILLEGAL:
386 // Invalid ciConstant returned due to OutOfMemoryError in the CI
387 assert(C->env()->failing(), "otherwise should not see this");
388 // These always occur because of object types; we are going to
389 // bail out anyway, so make the stack depths match up
390 push( zerocon(T_OBJECT) );
391 return false;
392 }
393
394 if (con_type == NULL)
395 // we cannot inline the oop, but we can use it later to narrow a type
396 return false;
397
398 push_node(constant.basic_type(), makecon(con_type));
399 return true;
400 }
401
402
403 //=============================================================================
404 void Parse::do_anewarray() {
405 bool will_link;
406 ciKlass* klass = iter().get_klass(will_link);
407
408 // Uncommon Trap when class that array contains is not loaded
409 // we need the loaded class for the rest of graph; do not
410 // initialize the container class (see Java spec)!!!
411 assert(will_link, "anewarray: typeflow responsibility");
412
413 ciObjArrayKlass* array_klass = ciObjArrayKlass::make(klass);
414 // Check that array_klass object is loaded
415 if (!array_klass->is_loaded()) {
416 // Generate uncommon_trap for unloaded array_class
417 uncommon_trap(Deoptimization::Reason_unloaded,
418 Deoptimization::Action_reinterpret,
419 array_klass);
420 return;
421 }
422
423 kill_dead_locals();
424
425 const TypeKlassPtr* array_klass_type = TypeKlassPtr::make(array_klass);
426 Node* count_val = pop();
427 Node* obj = new_array(makecon(array_klass_type), count_val, 1);
428 push(obj);
429 }
430
431
432 void Parse::do_newarray(BasicType elem_type) {
433 kill_dead_locals();
434
435 Node* count_val = pop();
436 const TypeKlassPtr* array_klass = TypeKlassPtr::make(ciTypeArrayKlass::make(elem_type));
437 Node* obj = new_array(makecon(array_klass), count_val, 1);
438 // Push resultant oop onto stack
439 push(obj);
440 }
441
442 // Expand simple expressions like new int[3][5] and new Object[2][nonConLen].
443 // Also handle the degenerate 1-dimensional case of anewarray.
444 Node* Parse::expand_multianewarray(ciArrayKlass* array_klass, Node* *lengths, int ndimensions, int nargs) {
445 Node* length = lengths[0];
446 assert(length != NULL, "");
447 Node* array = new_array(makecon(TypeKlassPtr::make(array_klass)), length, nargs);
448 if (ndimensions > 1) {
449 jint length_con = find_int_con(length, -1);
450 guarantee(length_con >= 0, "non-constant multianewarray");
451 ciArrayKlass* array_klass_1 = array_klass->as_obj_array_klass()->element_klass()->as_array_klass();
452 const TypePtr* adr_type = TypeAryPtr::OOPS;
453 const TypeOopPtr* elemtype = _gvn.type(array)->is_aryptr()->elem()->make_oopptr();
454 const intptr_t header = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
455 for (jint i = 0; i < length_con; i++) {
456 Node* elem = expand_multianewarray(array_klass_1, &lengths[1], ndimensions-1, nargs);
457 intptr_t offset = header + ((intptr_t)i << LogBytesPerHeapOop);
458 Node* eaddr = basic_plus_adr(array, offset);
459 store_oop_to_array(control(), array, eaddr, adr_type, elem, elemtype, T_OBJECT, MemNode::unordered);
460 }
461 }
462 return array;
463 }
464
465 void Parse::do_multianewarray() {
466 int ndimensions = iter().get_dimensions();
467
468 // the m-dimensional array
469 bool will_link;
470 ciArrayKlass* array_klass = iter().get_klass(will_link)->as_array_klass();
471 assert(will_link, "multianewarray: typeflow responsibility");
472
473 // Note: Array classes are always initialized; no is_initialized check.
474
475 kill_dead_locals();
476
477 // get the lengths from the stack (first dimension is on top)
478 Node** length = NEW_RESOURCE_ARRAY(Node*, ndimensions + 1);
479 length[ndimensions] = NULL; // terminating null for make_runtime_call
480 int j;
481 for (j = ndimensions-1; j >= 0 ; j--) length[j] = pop();
482
483 // The original expression was of this form: new T[length0][length1]...
484 // It is often the case that the lengths are small (except the last).
485 // If that happens, use the fast 1-d creator a constant number of times.
486 const jint expand_limit = MIN2((juint)MultiArrayExpandLimit, (juint)100);
487 jint expand_count = 1; // count of allocations in the expansion
488 jint expand_fanout = 1; // running total fanout
489 for (j = 0; j < ndimensions-1; j++) {
490 jint dim_con = find_int_con(length[j], -1);
491 expand_fanout *= dim_con;
492 expand_count += expand_fanout; // count the level-J sub-arrays
493 if (dim_con <= 0
494 || dim_con > expand_limit
495 || expand_count > expand_limit) {
496 expand_count = 0;
497 break;
498 }
499 }
500
501 // Can use multianewarray instead of [a]newarray if only one dimension,
502 // or if all non-final dimensions are small constants.
503 if (ndimensions == 1 || (1 <= expand_count && expand_count <= expand_limit)) {
504 Node* obj = NULL;
505 // Set the original stack and the reexecute bit for the interpreter
506 // to reexecute the multianewarray bytecode if deoptimization happens.
507 // Do it unconditionally even for one dimension multianewarray.
508 // Note: the reexecute bit will be set in GraphKit::add_safepoint_edges()
509 // when AllocateArray node for newarray is created.
510 { PreserveReexecuteState preexecs(this);
511 inc_sp(ndimensions);
512 // Pass 0 as nargs since uncommon trap code does not need to restore stack.
513 obj = expand_multianewarray(array_klass, &length[0], ndimensions, 0);
514 } //original reexecute and sp are set back here
515 push(obj);
516 return;
517 }
518
519 address fun = NULL;
520 switch (ndimensions) {
521 case 1: ShouldNotReachHere(); break;
522 case 2: fun = OptoRuntime::multianewarray2_Java(); break;
523 case 3: fun = OptoRuntime::multianewarray3_Java(); break;
524 case 4: fun = OptoRuntime::multianewarray4_Java(); break;
525 case 5: fun = OptoRuntime::multianewarray5_Java(); break;
526 };
527 Node* c = NULL;
528
529 if (fun != NULL) {
530 c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
531 OptoRuntime::multianewarray_Type(ndimensions),
532 fun, NULL, TypeRawPtr::BOTTOM,
533 makecon(TypeKlassPtr::make(array_klass)),
534 length[0], length[1], length[2],
535 (ndimensions > 2) ? length[3] : NULL,
536 (ndimensions > 3) ? length[4] : NULL);
537 } else {
538 // Create a java array for dimension sizes
539 Node* dims = NULL;
540 { PreserveReexecuteState preexecs(this);
541 inc_sp(ndimensions);
542 Node* dims_array_klass = makecon(TypeKlassPtr::make(ciArrayKlass::make(ciType::make(T_INT))));
543 dims = new_array(dims_array_klass, intcon(ndimensions), 0);
544
545 // Fill-in it with values
546 for (j = 0; j < ndimensions; j++) {
547 Node *dims_elem = array_element_address(dims, intcon(j), T_INT);
548 store_to_memory(control(), dims_elem, length[j], T_INT, TypeAryPtr::INTS, MemNode::unordered);
549 }
550 }
551
552 c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
553 OptoRuntime::multianewarrayN_Type(),
554 OptoRuntime::multianewarrayN_Java(), NULL, TypeRawPtr::BOTTOM,
555 makecon(TypeKlassPtr::make(array_klass)),
556 dims);
557 }
558 make_slow_call_ex(c, env()->Throwable_klass(), false);
559
560 Node* res = _gvn.transform(new (C) ProjNode(c, TypeFunc::Parms));
561
562 const Type* type = TypeOopPtr::make_from_klass_raw(array_klass);
563
564 // Improve the type: We know it's not null, exact, and of a given length.
565 type = type->is_ptr()->cast_to_ptr_type(TypePtr::NotNull);
566 type = type->is_aryptr()->cast_to_exactness(true);
567
568 const TypeInt* ltype = _gvn.find_int_type(length[0]);
569 if (ltype != NULL)
570 type = type->is_aryptr()->cast_to_size(ltype);
571
572 // We cannot sharpen the nested sub-arrays, since the top level is mutable.
573
574 Node* cast = _gvn.transform( new (C) CheckCastPPNode(control(), res, type) );
575 push(cast);
576
577 // Possible improvements:
578 // - Make a fast path for small multi-arrays. (W/ implicit init. loops.)
579 // - Issue CastII against length[*] values, to TypeInt::POS.
580 }