1 /*
2 * Copyright (c) 1998, 2010, 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.
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23 */
24
25 #include "incls/_precompiled.incl"
26 #include "incls/_parse3.cpp.incl"
27
28 //=============================================================================
29 // Helper methods for _get* and _put* bytecodes
30 //=============================================================================
31 bool Parse::static_field_ok_in_clinit(ciField *field, ciMethod *method) {
32 // Could be the field_holder's <clinit> method, or <clinit> for a subklass.
33 // Better to check now than to Deoptimize as soon as we execute
34 assert( field->is_static(), "Only check if field is static");
35 // is_being_initialized() is too generous. It allows access to statics
36 // by threads that are not running the <clinit> before the <clinit> finishes.
37 // return field->holder()->is_being_initialized();
38
39 // The following restriction is correct but conservative.
40 // It is also desirable to allow compilation of methods called from <clinit>
41 // but this generated code will need to be made safe for execution by
42 // other threads, or the transition from interpreted to compiled code would
43 // need to be guarded.
44 ciInstanceKlass *field_holder = field->holder();
45
46 bool access_OK = false;
47 if (method->holder()->is_subclass_of(field_holder)) {
48 if (method->is_static()) {
49 if (method->name() == ciSymbol::class_initializer_name()) {
50 // OK to access static fields inside initializer
51 access_OK = true;
52 }
53 } else {
54 if (method->name() == ciSymbol::object_initializer_name()) {
55 // It's also OK to access static fields inside a constructor,
56 // because any thread calling the constructor must first have
57 // synchronized on the class by executing a '_new' bytecode.
58 access_OK = true;
59 }
60 }
61 }
62
63 return access_OK;
64
65 }
66
67
68 void Parse::do_field_access(bool is_get, bool is_field) {
69 bool will_link;
70 ciField* field = iter().get_field(will_link);
71 assert(will_link, "getfield: typeflow responsibility");
72
73 ciInstanceKlass* field_holder = field->holder();
74
75 if (is_field == field->is_static()) {
76 // Interpreter will throw java_lang_IncompatibleClassChangeError
77 // Check this before allowing <clinit> methods to access static fields
78 uncommon_trap(Deoptimization::Reason_unhandled,
79 Deoptimization::Action_none);
80 return;
81 }
82
83 if (!is_field && !field_holder->is_initialized()) {
84 if (!static_field_ok_in_clinit(field, method())) {
85 uncommon_trap(Deoptimization::Reason_uninitialized,
86 Deoptimization::Action_reinterpret,
87 NULL, "!static_field_ok_in_clinit");
88 return;
89 }
90 }
91
92 assert(field->will_link(method()->holder(), bc()), "getfield: typeflow responsibility");
93
94 // Note: We do not check for an unloaded field type here any more.
95
96 // Generate code for the object pointer.
97 Node* obj;
98 if (is_field) {
99 int obj_depth = is_get ? 0 : field->type()->size();
100 obj = do_null_check(peek(obj_depth), T_OBJECT);
101 // Compile-time detect of null-exception?
102 if (stopped()) return;
103
104 const TypeInstPtr *tjp = TypeInstPtr::make(TypePtr::NotNull, iter().get_declared_field_holder());
105 assert(_gvn.type(obj)->higher_equal(tjp), "cast_up is no longer needed");
106
107 if (is_get) {
108 --_sp; // pop receiver before getting
109 do_get_xxx(tjp, obj, field, is_field);
110 } else {
111 do_put_xxx(tjp, obj, field, is_field);
112 --_sp; // pop receiver after putting
113 }
114 } else {
115 const TypeKlassPtr* tkp = TypeKlassPtr::make(field_holder);
116 obj = _gvn.makecon(tkp);
117 if (is_get) {
118 do_get_xxx(tkp, obj, field, is_field);
119 } else {
120 do_put_xxx(tkp, obj, field, is_field);
121 }
122 }
123 }
124
125
126 void Parse::do_get_xxx(const TypePtr* obj_type, Node* obj, ciField* field, bool is_field) {
127 // Does this field have a constant value? If so, just push the value.
128 if (field->is_constant()) {
129 if (field->is_static()) {
130 // final static field
131 if (push_constant(field->constant_value()))
132 return;
133 }
134 else {
135 // final non-static field of a trusted class ({java,sun}.dyn
136 // classes).
137 if (obj->is_Con()) {
138 const TypeOopPtr* oop_ptr = obj->bottom_type()->isa_oopptr();
139 ciObject* constant_oop = oop_ptr->const_oop();
140 ciConstant constant = field->constant_value_of(constant_oop);
141
142 if (push_constant(constant, true))
143 return;
144 }
145 }
146 }
147
148 ciType* field_klass = field->type();
149 bool is_vol = field->is_volatile();
150
151 // Compute address and memory type.
152 int offset = field->offset_in_bytes();
153 const TypePtr* adr_type = C->alias_type(field)->adr_type();
154 Node *adr = basic_plus_adr(obj, obj, offset);
155 BasicType bt = field->layout_type();
156
157 // Build the resultant type of the load
158 const Type *type;
159
160 bool must_assert_null = false;
161
162 if( bt == T_OBJECT ) {
163 if (!field->type()->is_loaded()) {
164 type = TypeInstPtr::BOTTOM;
165 must_assert_null = true;
166 } else if (field->is_constant() && field->is_static()) {
167 // This can happen if the constant oop is non-perm.
168 ciObject* con = field->constant_value().as_object();
169 // Do not "join" in the previous type; it doesn't add value,
170 // and may yield a vacuous result if the field is of interface type.
171 type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
172 assert(type != NULL, "field singleton type must be consistent");
173 } else {
174 type = TypeOopPtr::make_from_klass(field_klass->as_klass());
175 }
176 } else {
177 type = Type::get_const_basic_type(bt);
178 }
179 // Build the load.
180 Node* ld = make_load(NULL, adr, type, bt, adr_type, is_vol);
181
182 // Adjust Java stack
183 if (type2size[bt] == 1)
184 push(ld);
185 else
186 push_pair(ld);
187
188 if (must_assert_null) {
189 // Do not take a trap here. It's possible that the program
190 // will never load the field's class, and will happily see
191 // null values in this field forever. Don't stumble into a
192 // trap for such a program, or we might get a long series
193 // of useless recompilations. (Or, we might load a class
194 // which should not be loaded.) If we ever see a non-null
195 // value, we will then trap and recompile. (The trap will
196 // not need to mention the class index, since the class will
197 // already have been loaded if we ever see a non-null value.)
198 // uncommon_trap(iter().get_field_signature_index());
199 #ifndef PRODUCT
200 if (PrintOpto && (Verbose || WizardMode)) {
201 method()->print_name(); tty->print_cr(" asserting nullness of field at bci: %d", bci());
202 }
203 #endif
204 if (C->log() != NULL) {
205 C->log()->elem("assert_null reason='field' klass='%d'",
206 C->log()->identify(field->type()));
207 }
208 // If there is going to be a trap, put it at the next bytecode:
209 set_bci(iter().next_bci());
210 do_null_assert(peek(), T_OBJECT);
211 set_bci(iter().cur_bci()); // put it back
212 }
213
214 // If reference is volatile, prevent following memory ops from
215 // floating up past the volatile read. Also prevents commoning
216 // another volatile read.
217 if (field->is_volatile()) {
218 // Memory barrier includes bogus read of value to force load BEFORE membar
219 insert_mem_bar(Op_MemBarAcquire, ld);
220 }
221 }
222
223 void Parse::do_put_xxx(const TypePtr* obj_type, Node* obj, ciField* field, bool is_field) {
224 bool is_vol = field->is_volatile();
225 // If reference is volatile, prevent following memory ops from
226 // floating down past the volatile write. Also prevents commoning
227 // another volatile read.
228 if (is_vol) insert_mem_bar(Op_MemBarRelease);
229
230 // Compute address and memory type.
231 int offset = field->offset_in_bytes();
232 const TypePtr* adr_type = C->alias_type(field)->adr_type();
233 Node* adr = basic_plus_adr(obj, obj, offset);
234 BasicType bt = field->layout_type();
235 // Value to be stored
236 Node* val = type2size[bt] == 1 ? pop() : pop_pair();
237 // Round doubles before storing
238 if (bt == T_DOUBLE) val = dstore_rounding(val);
239
240 // Store the value.
241 Node* store;
242 if (bt == T_OBJECT) {
243 const TypeOopPtr* field_type;
244 if (!field->type()->is_loaded()) {
245 field_type = TypeInstPtr::BOTTOM;
246 } else {
247 field_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
248 }
249 store = store_oop_to_object( control(), obj, adr, adr_type, val, field_type, bt);
250 } else {
251 store = store_to_memory( control(), adr, val, bt, adr_type, is_vol );
252 }
253
254 // If reference is volatile, prevent following volatiles ops from
255 // floating up before the volatile write.
256 if (is_vol) {
257 // First place the specific membar for THIS volatile index. This first
258 // membar is dependent on the store, keeping any other membars generated
259 // below from floating up past the store.
260 int adr_idx = C->get_alias_index(adr_type);
261 insert_mem_bar_volatile(Op_MemBarVolatile, adr_idx, store);
262
263 // Now place a membar for AliasIdxBot for the unknown yet-to-be-parsed
264 // volatile alias indices. Skip this if the membar is redundant.
265 if (adr_idx != Compile::AliasIdxBot) {
266 insert_mem_bar_volatile(Op_MemBarVolatile, Compile::AliasIdxBot, store);
267 }
268
269 // Finally, place alias-index-specific membars for each volatile index
270 // that isn't the adr_idx membar. Typically there's only 1 or 2.
271 for( int i = Compile::AliasIdxRaw; i < C->num_alias_types(); i++ ) {
272 if (i != adr_idx && C->alias_type(i)->is_volatile()) {
273 insert_mem_bar_volatile(Op_MemBarVolatile, i, store);
274 }
275 }
276 }
277
278 // If the field is final, the rules of Java say we are in <init> or <clinit>.
279 // Note the presence of writes to final non-static fields, so that we
280 // can insert a memory barrier later on to keep the writes from floating
281 // out of the constructor.
282 if (is_field && field->is_final()) {
283 set_wrote_final(true);
284 }
285 }
286
287
288 bool Parse::push_constant(ciConstant constant, bool require_constant) {
289 switch (constant.basic_type()) {
290 case T_BOOLEAN: push( intcon(constant.as_boolean()) ); break;
291 case T_INT: push( intcon(constant.as_int()) ); break;
292 case T_CHAR: push( intcon(constant.as_char()) ); break;
293 case T_BYTE: push( intcon(constant.as_byte()) ); break;
294 case T_SHORT: push( intcon(constant.as_short()) ); break;
295 case T_FLOAT: push( makecon(TypeF::make(constant.as_float())) ); break;
296 case T_DOUBLE: push_pair( makecon(TypeD::make(constant.as_double())) ); break;
297 case T_LONG: push_pair( longcon(constant.as_long()) ); break;
298 case T_ARRAY:
299 case T_OBJECT: {
300 // cases:
301 // can_be_constant = (oop not scavengable || ScavengeRootsInCode != 0)
302 // should_be_constant = (oop not scavengable || ScavengeRootsInCode >= 2)
303 // An oop is not scavengable if it is in the perm gen.
304 ciObject* oop_constant = constant.as_object();
305 if (oop_constant->is_null_object()) {
306 push( zerocon(T_OBJECT) );
307 break;
308 } else if (require_constant || oop_constant->should_be_constant()) {
309 push( makecon(TypeOopPtr::make_from_constant(oop_constant, require_constant)) );
310 break;
311 } else {
312 // we cannot inline the oop, but we can use it later to narrow a type
313 return false;
314 }
315 }
316 case T_ILLEGAL: {
317 // Invalid ciConstant returned due to OutOfMemoryError in the CI
318 assert(C->env()->failing(), "otherwise should not see this");
319 // These always occur because of object types; we are going to
320 // bail out anyway, so make the stack depths match up
321 push( zerocon(T_OBJECT) );
322 return false;
323 }
324 default:
325 ShouldNotReachHere();
326 return false;
327 }
328
329 // success
330 return true;
331 }
332
333
334
335 //=============================================================================
336 void Parse::do_anewarray() {
337 bool will_link;
338 ciKlass* klass = iter().get_klass(will_link);
339
340 // Uncommon Trap when class that array contains is not loaded
341 // we need the loaded class for the rest of graph; do not
342 // initialize the container class (see Java spec)!!!
343 assert(will_link, "anewarray: typeflow responsibility");
344
345 ciObjArrayKlass* array_klass = ciObjArrayKlass::make(klass);
346 // Check that array_klass object is loaded
347 if (!array_klass->is_loaded()) {
348 // Generate uncommon_trap for unloaded array_class
349 uncommon_trap(Deoptimization::Reason_unloaded,
350 Deoptimization::Action_reinterpret,
351 array_klass);
352 return;
353 }
354
355 kill_dead_locals();
356
357 const TypeKlassPtr* array_klass_type = TypeKlassPtr::make(array_klass);
358 Node* count_val = pop();
359 Node* obj = new_array(makecon(array_klass_type), count_val, 1);
360 push(obj);
361 }
362
363
364 void Parse::do_newarray(BasicType elem_type) {
365 kill_dead_locals();
366
367 Node* count_val = pop();
368 const TypeKlassPtr* array_klass = TypeKlassPtr::make(ciTypeArrayKlass::make(elem_type));
369 Node* obj = new_array(makecon(array_klass), count_val, 1);
370 // Push resultant oop onto stack
371 push(obj);
372 }
373
374 // Expand simple expressions like new int[3][5] and new Object[2][nonConLen].
375 // Also handle the degenerate 1-dimensional case of anewarray.
376 Node* Parse::expand_multianewarray(ciArrayKlass* array_klass, Node* *lengths, int ndimensions, int nargs) {
377 Node* length = lengths[0];
378 assert(length != NULL, "");
379 Node* array = new_array(makecon(TypeKlassPtr::make(array_klass)), length, nargs);
380 if (ndimensions > 1) {
381 jint length_con = find_int_con(length, -1);
382 guarantee(length_con >= 0, "non-constant multianewarray");
383 ciArrayKlass* array_klass_1 = array_klass->as_obj_array_klass()->element_klass()->as_array_klass();
384 const TypePtr* adr_type = TypeAryPtr::OOPS;
385 const TypeOopPtr* elemtype = _gvn.type(array)->is_aryptr()->elem()->make_oopptr();
386 const intptr_t header = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
387 for (jint i = 0; i < length_con; i++) {
388 Node* elem = expand_multianewarray(array_klass_1, &lengths[1], ndimensions-1, nargs);
389 intptr_t offset = header + ((intptr_t)i << LogBytesPerHeapOop);
390 Node* eaddr = basic_plus_adr(array, offset);
391 store_oop_to_array(control(), array, eaddr, adr_type, elem, elemtype, T_OBJECT);
392 }
393 }
394 return array;
395 }
396
397 void Parse::do_multianewarray() {
398 int ndimensions = iter().get_dimensions();
399
400 // the m-dimensional array
401 bool will_link;
402 ciArrayKlass* array_klass = iter().get_klass(will_link)->as_array_klass();
403 assert(will_link, "multianewarray: typeflow responsibility");
404
405 // Note: Array classes are always initialized; no is_initialized check.
406
407 enum { MAX_DIMENSION = 5 };
408 if (ndimensions > MAX_DIMENSION || ndimensions <= 0) {
409 uncommon_trap(Deoptimization::Reason_unhandled,
410 Deoptimization::Action_none);
411 return;
412 }
413
414 kill_dead_locals();
415
416 // get the lengths from the stack (first dimension is on top)
417 Node* length[MAX_DIMENSION+1];
418 length[ndimensions] = NULL; // terminating null for make_runtime_call
419 int j;
420 for (j = ndimensions-1; j >= 0 ; j--) length[j] = pop();
421
422 // The original expression was of this form: new T[length0][length1]...
423 // It is often the case that the lengths are small (except the last).
424 // If that happens, use the fast 1-d creator a constant number of times.
425 const jint expand_limit = MIN2((juint)MultiArrayExpandLimit, (juint)100);
426 jint expand_count = 1; // count of allocations in the expansion
427 jint expand_fanout = 1; // running total fanout
428 for (j = 0; j < ndimensions-1; j++) {
429 jint dim_con = find_int_con(length[j], -1);
430 expand_fanout *= dim_con;
431 expand_count += expand_fanout; // count the level-J sub-arrays
432 if (dim_con <= 0
433 || dim_con > expand_limit
434 || expand_count > expand_limit) {
435 expand_count = 0;
436 break;
437 }
438 }
439
440 // Can use multianewarray instead of [a]newarray if only one dimension,
441 // or if all non-final dimensions are small constants.
442 if (ndimensions == 1 || (1 <= expand_count && expand_count <= expand_limit)) {
443 Node* obj = NULL;
444 // Set the original stack and the reexecute bit for the interpreter
445 // to reexecute the multianewarray bytecode if deoptimization happens.
446 // Do it unconditionally even for one dimension multianewarray.
447 // Note: the reexecute bit will be set in GraphKit::add_safepoint_edges()
448 // when AllocateArray node for newarray is created.
449 { PreserveReexecuteState preexecs(this);
450 _sp += ndimensions;
451 // Pass 0 as nargs since uncommon trap code does not need to restore stack.
452 obj = expand_multianewarray(array_klass, &length[0], ndimensions, 0);
453 } //original reexecute and sp are set back here
454 push(obj);
455 return;
456 }
457
458 address fun = NULL;
459 switch (ndimensions) {
460 //case 1: Actually, there is no case 1. It's handled by new_array.
461 case 2: fun = OptoRuntime::multianewarray2_Java(); break;
462 case 3: fun = OptoRuntime::multianewarray3_Java(); break;
463 case 4: fun = OptoRuntime::multianewarray4_Java(); break;
464 case 5: fun = OptoRuntime::multianewarray5_Java(); break;
465 default: ShouldNotReachHere();
466 };
467
468 Node* c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
469 OptoRuntime::multianewarray_Type(ndimensions),
470 fun, NULL, TypeRawPtr::BOTTOM,
471 makecon(TypeKlassPtr::make(array_klass)),
472 length[0], length[1], length[2],
473 length[3], length[4]);
474 Node* res = _gvn.transform(new (C, 1) ProjNode(c, TypeFunc::Parms));
475
476 const Type* type = TypeOopPtr::make_from_klass_raw(array_klass);
477
478 // Improve the type: We know it's not null, exact, and of a given length.
479 type = type->is_ptr()->cast_to_ptr_type(TypePtr::NotNull);
480 type = type->is_aryptr()->cast_to_exactness(true);
481
482 const TypeInt* ltype = _gvn.find_int_type(length[0]);
483 if (ltype != NULL)
484 type = type->is_aryptr()->cast_to_size(ltype);
485
486 // We cannot sharpen the nested sub-arrays, since the top level is mutable.
487
488 Node* cast = _gvn.transform( new (C, 2) CheckCastPPNode(control(), res, type) );
489 push(cast);
490
491 // Possible improvements:
492 // - Make a fast path for small multi-arrays. (W/ implicit init. loops.)
493 // - Issue CastII against length[*] values, to TypeInt::POS.
494 }