1 /*
2 * Copyright (c) 1998, 2011, 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 assert(field->will_link(method()->holder(), bc()), "getfield: typeflow responsibility");
104
105 // Note: We do not check for an unloaded field type here any more.
106
107 // Generate code for the object pointer.
108 Node* obj;
109 if (is_field) {
110 int obj_depth = is_get ? 0 : field->type()->size();
111 obj = do_null_check(peek(obj_depth), T_OBJECT);
112 // Compile-time detect of null-exception?
113 if (stopped()) return;
114
115 #ifdef ASSERT
116 const TypeInstPtr *tjp = TypeInstPtr::make(TypePtr::NotNull, iter().get_declared_field_holder());
117 assert(_gvn.type(obj)->higher_equal(tjp), "cast_up is no longer needed");
118 #endif
119
120 if (is_get) {
121 --_sp; // pop receiver before getting
122 do_get_xxx(obj, field, is_field);
123 } else {
124 do_put_xxx(obj, field, is_field);
125 --_sp; // pop receiver after putting
126 }
127 } else {
128 const TypeInstPtr* tip = TypeInstPtr::make(field_holder->java_mirror());
129 obj = _gvn.makecon(tip);
130 if (is_get) {
131 do_get_xxx(obj, field, is_field);
132 } else {
133 do_put_xxx(obj, field, is_field);
134 }
135 }
136 }
137
138
139 void Parse::do_get_xxx(Node* obj, ciField* field, bool is_field) {
140 // Does this field have a constant value? If so, just push the value.
141 if (field->is_constant()) {
142 if (field->is_static()) {
143 // final static field
144 if (push_constant(field->constant_value()))
145 return;
146 }
147 else {
148 // final non-static field of a trusted class (classes in
149 // java.lang.invoke and sun.invoke packages and subpackages).
150 if (obj->is_Con()) {
151 const TypeOopPtr* oop_ptr = obj->bottom_type()->isa_oopptr();
152 ciObject* constant_oop = oop_ptr->const_oop();
153 ciConstant constant = field->constant_value_of(constant_oop);
154
155 if (push_constant(constant, true))
156 return;
157 }
158 }
159 }
160
161 ciType* field_klass = field->type();
162 bool is_vol = field->is_volatile();
163
164 // Compute address and memory type.
165 int offset = field->offset_in_bytes();
166 const TypePtr* adr_type = C->alias_type(field)->adr_type();
167 Node *adr = basic_plus_adr(obj, obj, offset);
168 BasicType bt = field->layout_type();
169
170 // Build the resultant type of the load
171 const Type *type;
172
173 bool must_assert_null = false;
174
175 if( bt == T_OBJECT ) {
176 if (!field->type()->is_loaded()) {
177 type = TypeInstPtr::BOTTOM;
178 must_assert_null = true;
179 } else if (field->is_constant() && field->is_static()) {
180 // This can happen if the constant oop is non-perm.
181 ciObject* con = field->constant_value().as_object();
182 // Do not "join" in the previous type; it doesn't add value,
183 // and may yield a vacuous result if the field is of interface type.
184 type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
185 assert(type != NULL, "field singleton type must be consistent");
186 } else {
187 type = TypeOopPtr::make_from_klass(field_klass->as_klass());
188 }
189 } else {
190 type = Type::get_const_basic_type(bt);
191 }
192 // Build the load.
193 Node* ld = make_load(NULL, adr, type, bt, adr_type, is_vol);
194
195 // Adjust Java stack
196 if (type2size[bt] == 1)
197 push(ld);
198 else
199 push_pair(ld);
200
201 if (must_assert_null) {
202 // Do not take a trap here. It's possible that the program
203 // will never load the field's class, and will happily see
204 // null values in this field forever. Don't stumble into a
205 // trap for such a program, or we might get a long series
206 // of useless recompilations. (Or, we might load a class
207 // which should not be loaded.) If we ever see a non-null
208 // value, we will then trap and recompile. (The trap will
209 // not need to mention the class index, since the class will
210 // already have been loaded if we ever see a non-null value.)
211 // uncommon_trap(iter().get_field_signature_index());
212 #ifndef PRODUCT
213 if (PrintOpto && (Verbose || WizardMode)) {
214 method()->print_name(); tty->print_cr(" asserting nullness of field at bci: %d", bci());
215 }
216 #endif
217 if (C->log() != NULL) {
218 C->log()->elem("assert_null reason='field' klass='%d'",
219 C->log()->identify(field->type()));
220 }
221 // If there is going to be a trap, put it at the next bytecode:
222 set_bci(iter().next_bci());
223 do_null_assert(peek(), T_OBJECT);
224 set_bci(iter().cur_bci()); // put it back
225 }
226
227 // If reference is volatile, prevent following memory ops from
228 // floating up past the volatile read. Also prevents commoning
229 // another volatile read.
230 if (field->is_volatile()) {
231 // Memory barrier includes bogus read of value to force load BEFORE membar
232 insert_mem_bar(Op_MemBarAcquire, ld);
233 }
234 }
235
236 void Parse::do_put_xxx(Node* obj, ciField* field, bool is_field) {
237 bool is_vol = field->is_volatile();
238 // If reference is volatile, prevent following memory ops from
239 // floating down past the volatile write. Also prevents commoning
240 // another volatile read.
241 if (is_vol) insert_mem_bar(Op_MemBarRelease);
242
243 // Compute address and memory type.
244 int offset = field->offset_in_bytes();
245 const TypePtr* adr_type = C->alias_type(field)->adr_type();
246 Node* adr = basic_plus_adr(obj, obj, offset);
247 BasicType bt = field->layout_type();
248 // Value to be stored
249 Node* val = type2size[bt] == 1 ? pop() : pop_pair();
250 // Round doubles before storing
251 if (bt == T_DOUBLE) val = dstore_rounding(val);
252
253 // Store the value.
254 Node* store;
255 if (bt == T_OBJECT) {
256 const TypeOopPtr* field_type;
257 if (!field->type()->is_loaded()) {
258 field_type = TypeInstPtr::BOTTOM;
259 } else {
260 field_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
261 }
262 store = store_oop_to_object( control(), obj, adr, adr_type, val, field_type, bt);
263 } else {
264 store = store_to_memory( control(), adr, val, bt, adr_type, is_vol );
265 }
266
267 // If reference is volatile, prevent following volatiles ops from
268 // floating up before the volatile write.
269 if (is_vol) {
270 // First place the specific membar for THIS volatile index. This first
271 // membar is dependent on the store, keeping any other membars generated
272 // below from floating up past the store.
273 int adr_idx = C->get_alias_index(adr_type);
274 insert_mem_bar_volatile(Op_MemBarVolatile, adr_idx, store);
275
276 // Now place a membar for AliasIdxBot for the unknown yet-to-be-parsed
277 // volatile alias indices. Skip this if the membar is redundant.
278 if (adr_idx != Compile::AliasIdxBot) {
279 insert_mem_bar_volatile(Op_MemBarVolatile, Compile::AliasIdxBot, store);
280 }
281
282 // Finally, place alias-index-specific membars for each volatile index
283 // that isn't the adr_idx membar. Typically there's only 1 or 2.
284 for( int i = Compile::AliasIdxRaw; i < C->num_alias_types(); i++ ) {
285 if (i != adr_idx && C->alias_type(i)->is_volatile()) {
286 insert_mem_bar_volatile(Op_MemBarVolatile, i, store);
287 }
288 }
289 }
290
291 // If the field is final, the rules of Java say we are in <init> or <clinit>.
292 // Note the presence of writes to final non-static fields, so that we
293 // can insert a memory barrier later on to keep the writes from floating
294 // out of the constructor.
295 if (is_field && field->is_final()) {
296 set_wrote_final(true);
297 }
298 }
299
300
301 bool Parse::push_constant(ciConstant constant, bool require_constant) {
302 switch (constant.basic_type()) {
303 case T_BOOLEAN: push( intcon(constant.as_boolean()) ); break;
304 case T_INT: push( intcon(constant.as_int()) ); break;
305 case T_CHAR: push( intcon(constant.as_char()) ); break;
306 case T_BYTE: push( intcon(constant.as_byte()) ); break;
307 case T_SHORT: push( intcon(constant.as_short()) ); break;
308 case T_FLOAT: push( makecon(TypeF::make(constant.as_float())) ); break;
309 case T_DOUBLE: push_pair( makecon(TypeD::make(constant.as_double())) ); break;
310 case T_LONG: push_pair( longcon(constant.as_long()) ); break;
311 case T_ARRAY:
312 case T_OBJECT: {
313 // cases:
314 // can_be_constant = (oop not scavengable || ScavengeRootsInCode != 0)
315 // should_be_constant = (oop not scavengable || ScavengeRootsInCode >= 2)
316 // An oop is not scavengable if it is in the perm gen.
317 ciObject* oop_constant = constant.as_object();
318 if (oop_constant->is_null_object()) {
319 push( zerocon(T_OBJECT) );
320 break;
321 } else if (require_constant || oop_constant->should_be_constant()) {
322 push( makecon(TypeOopPtr::make_from_constant(oop_constant, require_constant)) );
323 break;
324 } else {
325 // we cannot inline the oop, but we can use it later to narrow a type
326 return false;
327 }
328 }
329 case T_ILLEGAL: {
330 // Invalid ciConstant returned due to OutOfMemoryError in the CI
331 assert(C->env()->failing(), "otherwise should not see this");
332 // These always occur because of object types; we are going to
333 // bail out anyway, so make the stack depths match up
334 push( zerocon(T_OBJECT) );
335 return false;
336 }
337 default:
338 ShouldNotReachHere();
339 return false;
340 }
341
342 // success
343 return true;
344 }
345
346
347
348 //=============================================================================
349 void Parse::do_anewarray() {
350 bool will_link;
351 ciKlass* klass = iter().get_klass(will_link);
352
353 // Uncommon Trap when class that array contains is not loaded
354 // we need the loaded class for the rest of graph; do not
355 // initialize the container class (see Java spec)!!!
356 assert(will_link, "anewarray: typeflow responsibility");
357
358 ciObjArrayKlass* array_klass = ciObjArrayKlass::make(klass);
359 // Check that array_klass object is loaded
360 if (!array_klass->is_loaded()) {
361 // Generate uncommon_trap for unloaded array_class
362 uncommon_trap(Deoptimization::Reason_unloaded,
363 Deoptimization::Action_reinterpret,
364 array_klass);
365 return;
366 }
367
368 kill_dead_locals();
369
370 const TypeKlassPtr* array_klass_type = TypeKlassPtr::make(array_klass);
371 Node* count_val = pop();
372 Node* obj = new_array(makecon(array_klass_type), count_val, 1);
373 push(obj);
374 }
375
376
377 void Parse::do_newarray(BasicType elem_type) {
378 kill_dead_locals();
379
380 Node* count_val = pop();
381 const TypeKlassPtr* array_klass = TypeKlassPtr::make(ciTypeArrayKlass::make(elem_type));
382 Node* obj = new_array(makecon(array_klass), count_val, 1);
383 // Push resultant oop onto stack
384 push(obj);
385 }
386
387 // Expand simple expressions like new int[3][5] and new Object[2][nonConLen].
388 // Also handle the degenerate 1-dimensional case of anewarray.
389 Node* Parse::expand_multianewarray(ciArrayKlass* array_klass, Node* *lengths, int ndimensions, int nargs) {
390 Node* length = lengths[0];
391 assert(length != NULL, "");
392 Node* array = new_array(makecon(TypeKlassPtr::make(array_klass)), length, nargs);
393 if (ndimensions > 1) {
394 jint length_con = find_int_con(length, -1);
395 guarantee(length_con >= 0, "non-constant multianewarray");
396 ciArrayKlass* array_klass_1 = array_klass->as_obj_array_klass()->element_klass()->as_array_klass();
397 const TypePtr* adr_type = TypeAryPtr::OOPS;
398 const TypeOopPtr* elemtype = _gvn.type(array)->is_aryptr()->elem()->make_oopptr();
399 const intptr_t header = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
400 for (jint i = 0; i < length_con; i++) {
401 Node* elem = expand_multianewarray(array_klass_1, &lengths[1], ndimensions-1, nargs);
402 intptr_t offset = header + ((intptr_t)i << LogBytesPerHeapOop);
403 Node* eaddr = basic_plus_adr(array, offset);
404 store_oop_to_array(control(), array, eaddr, adr_type, elem, elemtype, T_OBJECT);
405 }
406 }
407 return array;
408 }
409
410 void Parse::do_multianewarray() {
411 int ndimensions = iter().get_dimensions();
412
413 // the m-dimensional array
414 bool will_link;
415 ciArrayKlass* array_klass = iter().get_klass(will_link)->as_array_klass();
416 assert(will_link, "multianewarray: typeflow responsibility");
417
418 // Note: Array classes are always initialized; no is_initialized check.
419
420 kill_dead_locals();
421
422 // get the lengths from the stack (first dimension is on top)
423 Node** length = NEW_RESOURCE_ARRAY(Node*, ndimensions + 1);
424 length[ndimensions] = NULL; // terminating null for make_runtime_call
425 int j;
426 for (j = ndimensions-1; j >= 0 ; j--) length[j] = pop();
427
428 // The original expression was of this form: new T[length0][length1]...
429 // It is often the case that the lengths are small (except the last).
430 // If that happens, use the fast 1-d creator a constant number of times.
431 const jint expand_limit = MIN2((juint)MultiArrayExpandLimit, (juint)100);
432 jint expand_count = 1; // count of allocations in the expansion
433 jint expand_fanout = 1; // running total fanout
434 for (j = 0; j < ndimensions-1; j++) {
435 jint dim_con = find_int_con(length[j], -1);
436 expand_fanout *= dim_con;
437 expand_count += expand_fanout; // count the level-J sub-arrays
438 if (dim_con <= 0
439 || dim_con > expand_limit
440 || expand_count > expand_limit) {
441 expand_count = 0;
442 break;
443 }
444 }
445
446 // Can use multianewarray instead of [a]newarray if only one dimension,
447 // or if all non-final dimensions are small constants.
448 if (ndimensions == 1 || (1 <= expand_count && expand_count <= expand_limit)) {
449 Node* obj = NULL;
450 // Set the original stack and the reexecute bit for the interpreter
451 // to reexecute the multianewarray bytecode if deoptimization happens.
452 // Do it unconditionally even for one dimension multianewarray.
453 // Note: the reexecute bit will be set in GraphKit::add_safepoint_edges()
454 // when AllocateArray node for newarray is created.
455 { PreserveReexecuteState preexecs(this);
456 _sp += ndimensions;
457 // Pass 0 as nargs since uncommon trap code does not need to restore stack.
458 obj = expand_multianewarray(array_klass, &length[0], ndimensions, 0);
459 } //original reexecute and sp are set back here
460 push(obj);
461 return;
462 }
463
464 address fun = NULL;
465 switch (ndimensions) {
466 case 1: ShouldNotReachHere(); break;
467 case 2: fun = OptoRuntime::multianewarray2_Java(); break;
468 case 3: fun = OptoRuntime::multianewarray3_Java(); break;
469 case 4: fun = OptoRuntime::multianewarray4_Java(); break;
470 case 5: fun = OptoRuntime::multianewarray5_Java(); break;
471 };
472 Node* c = NULL;
473
474 if (fun != NULL) {
475 c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
476 OptoRuntime::multianewarray_Type(ndimensions),
477 fun, NULL, TypeRawPtr::BOTTOM,
478 makecon(TypeKlassPtr::make(array_klass)),
479 length[0], length[1], length[2],
480 length[3], length[4]);
481 } else {
482 // Create a java array for dimension sizes
483 Node* dims = NULL;
484 { PreserveReexecuteState preexecs(this);
485 _sp += ndimensions;
486 Node* dims_array_klass = makecon(TypeKlassPtr::make(ciArrayKlass::make(ciType::make(T_INT))));
487 dims = new_array(dims_array_klass, intcon(ndimensions), 0);
488
489 // Fill-in it with values
490 for (j = 0; j < ndimensions; j++) {
491 Node *dims_elem = array_element_address(dims, intcon(j), T_INT);
492 store_to_memory(control(), dims_elem, length[j], T_INT, TypeAryPtr::INTS);
493 }
494 }
495
496 c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
497 OptoRuntime::multianewarrayN_Type(),
498 OptoRuntime::multianewarrayN_Java(), NULL, TypeRawPtr::BOTTOM,
499 makecon(TypeKlassPtr::make(array_klass)),
500 dims);
501 }
502
503 Node* res = _gvn.transform(new (C, 1) ProjNode(c, TypeFunc::Parms));
504
505 const Type* type = TypeOopPtr::make_from_klass_raw(array_klass);
506
507 // Improve the type: We know it's not null, exact, and of a given length.
508 type = type->is_ptr()->cast_to_ptr_type(TypePtr::NotNull);
509 type = type->is_aryptr()->cast_to_exactness(true);
510
511 const TypeInt* ltype = _gvn.find_int_type(length[0]);
512 if (ltype != NULL)
513 type = type->is_aryptr()->cast_to_size(ltype);
514
515 // We cannot sharpen the nested sub-arrays, since the top level is mutable.
516
517 Node* cast = _gvn.transform( new (C, 2) CheckCastPPNode(control(), res, type) );
518 push(cast);
519
520 // Possible improvements:
521 // - Make a fast path for small multi-arrays. (W/ implicit init. loops.)
522 // - Issue CastII against length[*] values, to TypeInt::POS.
523 }