1 /*
  2  * Copyright (c) 1998, 2019, 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.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 void Parse::do_field_access(bool is_get, bool is_field) {
 44   bool will_link;
 45   ciField* field = iter().get_field(will_link);
 46   assert(will_link, "getfield: typeflow responsibility");
 47 
 48   ciInstanceKlass* field_holder = field->holder();
 49 
 50   if (is_field == field->is_static()) {
 51     // Interpreter will throw java_lang_IncompatibleClassChangeError
 52     // Check this before allowing <clinit> methods to access static fields
 53     uncommon_trap(Deoptimization::Reason_unhandled,
 54                   Deoptimization::Action_none);
 55     return;
 56   }
 57 
 58   // Deoptimize on putfield writes to call site target field outside of CallSite ctor.
 59   if (!is_get && field->is_call_site_target() &&
 60       !(method()->holder() == field_holder && method()->is_object_initializer())) {
 61     uncommon_trap(Deoptimization::Reason_unhandled,
 62                   Deoptimization::Action_reinterpret,
 63                   NULL, "put to call site target field");
 64     return;
 65   }
 66 
 67   if (C->needs_clinit_barrier(field, method())) {
 68     clinit_barrier(field_holder, method());
 69     if (stopped())  return;
 70   }
 71 
 72   assert(field->will_link(method(), bc()), "getfield: typeflow responsibility");
 73 
 74   // Note:  We do not check for an unloaded field type here any more.
 75 
 76   // Generate code for the object pointer.
 77   Node* obj;
 78   if (is_field) {
 79     int obj_depth = is_get ? 0 : field->type()->size();
 80     obj = null_check(peek(obj_depth));
 81     // Compile-time detect of null-exception?
 82     if (stopped())  return;
 83 
 84 #ifdef ASSERT
 85     const TypeInstPtr *tjp = TypeInstPtr::make(TypePtr::NotNull, iter().get_declared_field_holder());
 86     assert(_gvn.type(obj)->higher_equal(tjp), "cast_up is no longer needed");
 87 #endif
 88 
 89     if (is_get) {
 90       (void) pop();  // pop receiver before getting
 91       do_get_xxx(obj, field, is_field);
 92     } else {
 93       do_put_xxx(obj, field, is_field);
 94       (void) pop();  // pop receiver after putting
 95     }
 96   } else {
 97     const TypeInstPtr* tip = TypeInstPtr::make(field_holder->java_mirror());
 98     obj = _gvn.makecon(tip);
 99     if (is_get) {
100       do_get_xxx(obj, field, is_field);
101     } else {
102       do_put_xxx(obj, field, is_field);
103     }
104   }
105 }
106 
107 
108 void Parse::do_get_xxx(Node* obj, ciField* field, bool is_field) {
109   BasicType bt = field->layout_type();
110 
111   // Does this field have a constant value?  If so, just push the value.
112   if (field->is_constant() &&
113       // Keep consistent with types found by ciTypeFlow: for an
114       // unloaded field type, ciTypeFlow::StateVector::do_getstatic()
115       // speculates the field is null. The code in the rest of this
116       // method does the same. We must not bypass it and use a non
117       // null constant here.
118       (bt != T_OBJECT || field->type()->is_loaded())) {
119     // final or stable field
120     Node* con = make_constant_from_field(field, obj);
121     if (con != NULL) {
122       push_node(field->layout_type(), con);
123       return;
124     }
125   }
126 
127   ciType* field_klass = field->type();
128   bool is_vol = field->is_volatile();
129 
130   // Compute address and memory type.
131   int offset = field->offset_in_bytes();
132   const TypePtr* adr_type = C->alias_type(field)->adr_type();
133   Node *adr = basic_plus_adr(obj, obj, offset);
134 
135   // Build the resultant type of the load
136   const Type *type;
137 
138   bool must_assert_null = false;
139 
140   DecoratorSet decorators = IN_HEAP;
141   decorators |= is_vol ? MO_SEQ_CST : MO_UNORDERED;
142 
143   bool is_obj = is_reference_type(bt);
144 
145   if (is_obj) {
146     if (!field->type()->is_loaded()) {
147       type = TypeInstPtr::BOTTOM;
148       must_assert_null = true;
149     } else if (field->is_static_constant()) {
150       // This can happen if the constant oop is non-perm.
151       ciObject* con = field->constant_value().as_object();
152       // Do not "join" in the previous type; it doesn't add value,
153       // and may yield a vacuous result if the field is of interface type.
154       if (con->is_null_object()) {
155         type = TypePtr::NULL_PTR;
156       } else {
157         type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
158       }
159       assert(type != NULL, "field singleton type must be consistent");
160     } else {
161       type = TypeOopPtr::make_from_klass(field_klass->as_klass());
162     }
163   } else {
164     type = Type::get_const_basic_type(bt);
165   }
166 
167   Node* ld = access_load_at(obj, adr, adr_type, type, bt, decorators);
168 
169   // Adjust Java stack
170   if (type2size[bt] == 1)
171     push(ld);
172   else
173     push_pair(ld);
174 
175   if (must_assert_null) {
176     // Do not take a trap here.  It's possible that the program
177     // will never load the field's class, and will happily see
178     // null values in this field forever.  Don't stumble into a
179     // trap for such a program, or we might get a long series
180     // of useless recompilations.  (Or, we might load a class
181     // which should not be loaded.)  If we ever see a non-null
182     // value, we will then trap and recompile.  (The trap will
183     // not need to mention the class index, since the class will
184     // already have been loaded if we ever see a non-null value.)
185     // uncommon_trap(iter().get_field_signature_index());
186     if (PrintOpto && (Verbose || WizardMode)) {
187       method()->print_name(); tty->print_cr(" asserting nullness of field at bci: %d", bci());
188     }
189     if (C->log() != NULL) {
190       C->log()->elem("assert_null reason='field' klass='%d'",
191                      C->log()->identify(field->type()));
192     }
193     // If there is going to be a trap, put it at the next bytecode:
194     set_bci(iter().next_bci());
195     null_assert(peek());
196     set_bci(iter().cur_bci()); // put it back
197   }
198 }
199 
200 void Parse::do_put_xxx(Node* obj, ciField* field, bool is_field) {
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   // Value to be stored
209   Node* val = type2size[bt] == 1 ? pop() : pop_pair();
210 
211   DecoratorSet decorators = IN_HEAP;
212   decorators |= is_vol ? MO_SEQ_CST : MO_UNORDERED;
213 
214   bool is_obj = is_reference_type(bt);
215 
216   // Store the value.
217   const Type* field_type;
218   if (!field->type()->is_loaded()) {
219     field_type = TypeInstPtr::BOTTOM;
220   } else {
221     if (is_obj) {
222       field_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
223     } else {
224       field_type = Type::BOTTOM;
225     }
226   }
227   access_store_at(obj, adr, adr_type, val, field_type, bt, decorators);
228 
229   if (is_field) {
230     // Remember we wrote a volatile field.
231     // For not multiple copy atomic cpu (ppc64) a barrier should be issued
232     // in constructors which have such stores. See do_exits() in parse1.cpp.
233     if (is_vol) {
234       set_wrote_volatile(true);
235     }
236     set_wrote_fields(true);
237 
238     // If the field is final, the rules of Java say we are in <init> or <clinit>.
239     // Note the presence of writes to final non-static fields, so that we
240     // can insert a memory barrier later on to keep the writes from floating
241     // out of the constructor.
242     // Any method can write a @Stable field; insert memory barriers after those also.
243     if (field->is_final()) {
244       set_wrote_final(true);
245       if (AllocateNode::Ideal_allocation(obj, &_gvn) != NULL) {
246         // Preserve allocation ptr to create precedent edge to it in membar
247         // generated on exit from constructor.
248         // Can't bind stable with its allocation, only record allocation for final field.
249         set_alloc_with_final(obj);
250       }
251     }
252     if (field->is_stable()) {
253       set_wrote_stable(true);
254     }
255   }
256 }
257 
258 //=============================================================================
259 void Parse::do_anewarray() {
260   bool will_link;
261   ciKlass* klass = iter().get_klass(will_link);
262 
263   // Uncommon Trap when class that array contains is not loaded
264   // we need the loaded class for the rest of graph; do not
265   // initialize the container class (see Java spec)!!!
266   assert(will_link, "anewarray: typeflow responsibility");
267 
268   ciObjArrayKlass* array_klass = ciObjArrayKlass::make(klass);
269   // Check that array_klass object is loaded
270   if (!array_klass->is_loaded()) {
271     // Generate uncommon_trap for unloaded array_class
272     uncommon_trap(Deoptimization::Reason_unloaded,
273                   Deoptimization::Action_reinterpret,
274                   array_klass);
275     return;
276   }
277 
278   kill_dead_locals();
279 
280   const TypeKlassPtr* array_klass_type = TypeKlassPtr::make(array_klass);
281   Node* count_val = pop();
282   Node* obj = new_array(makecon(array_klass_type), count_val, 1);
283   push(obj);
284 }
285 
286 
287 void Parse::do_newarray(BasicType elem_type) {
288   kill_dead_locals();
289 
290   Node*   count_val = pop();
291   const TypeKlassPtr* array_klass = TypeKlassPtr::make(ciTypeArrayKlass::make(elem_type));
292   Node*   obj = new_array(makecon(array_klass), count_val, 1);
293   // Push resultant oop onto stack
294   push(obj);
295 }
296 
297 // Expand simple expressions like new int[3][5] and new Object[2][nonConLen].
298 // Also handle the degenerate 1-dimensional case of anewarray.
299 Node* Parse::expand_multianewarray(ciArrayKlass* array_klass, Node* *lengths, int ndimensions, int nargs) {
300   Node* length = lengths[0];
301   assert(length != NULL, "");
302   Node* array = new_array(makecon(TypeKlassPtr::make(array_klass)), length, nargs);
303   if (ndimensions > 1) {
304     jint length_con = find_int_con(length, -1);
305     guarantee(length_con >= 0, "non-constant multianewarray");
306     ciArrayKlass* array_klass_1 = array_klass->as_obj_array_klass()->element_klass()->as_array_klass();
307     const TypePtr* adr_type = TypeAryPtr::OOPS;
308     const TypeOopPtr*    elemtype = _gvn.type(array)->is_aryptr()->elem()->make_oopptr();
309     const intptr_t header   = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
310     for (jint i = 0; i < length_con; i++) {
311       Node*    elem   = expand_multianewarray(array_klass_1, &lengths[1], ndimensions-1, nargs);
312       intptr_t offset = header + ((intptr_t)i << LogBytesPerHeapOop);
313       Node*    eaddr  = basic_plus_adr(array, offset);
314       access_store_at(array, eaddr, adr_type, elem, elemtype, T_OBJECT, IN_HEAP | IS_ARRAY);
315     }
316   }
317   return array;
318 }
319 
320 void Parse::do_multianewarray() {
321   int ndimensions = iter().get_dimensions();
322 
323   // the m-dimensional array
324   bool will_link;
325   ciArrayKlass* array_klass = iter().get_klass(will_link)->as_array_klass();
326   assert(will_link, "multianewarray: typeflow responsibility");
327 
328   // Note:  Array classes are always initialized; no is_initialized check.
329 
330   kill_dead_locals();
331 
332   // get the lengths from the stack (first dimension is on top)
333   Node** length = NEW_RESOURCE_ARRAY(Node*, ndimensions + 1);
334   length[ndimensions] = NULL;  // terminating null for make_runtime_call
335   int j;
336   for (j = ndimensions-1; j >= 0 ; j--) length[j] = pop();
337 
338   // The original expression was of this form: new T[length0][length1]...
339   // It is often the case that the lengths are small (except the last).
340   // If that happens, use the fast 1-d creator a constant number of times.
341   const int expand_limit = MIN2((int)MultiArrayExpandLimit, 100);
342   int expand_count = 1;        // count of allocations in the expansion
343   int expand_fanout = 1;       // running total fanout
344   for (j = 0; j < ndimensions-1; j++) {
345     int dim_con = find_int_con(length[j], -1);
346     expand_fanout *= dim_con;
347     expand_count  += expand_fanout; // count the level-J sub-arrays
348     if (dim_con <= 0
349         || dim_con > expand_limit
350         || expand_count > expand_limit) {
351       expand_count = 0;
352       break;
353     }
354   }
355 
356   // Can use multianewarray instead of [a]newarray if only one dimension,
357   // or if all non-final dimensions are small constants.
358   if (ndimensions == 1 || (1 <= expand_count && expand_count <= expand_limit)) {
359     Node* obj = NULL;
360     // Set the original stack and the reexecute bit for the interpreter
361     // to reexecute the multianewarray bytecode if deoptimization happens.
362     // Do it unconditionally even for one dimension multianewarray.
363     // Note: the reexecute bit will be set in GraphKit::add_safepoint_edges()
364     // when AllocateArray node for newarray is created.
365     { PreserveReexecuteState preexecs(this);
366       inc_sp(ndimensions);
367       // Pass 0 as nargs since uncommon trap code does not need to restore stack.
368       obj = expand_multianewarray(array_klass, &length[0], ndimensions, 0);
369     } //original reexecute and sp are set back here
370     push(obj);
371     return;
372   }
373 
374   address fun = NULL;
375   switch (ndimensions) {
376   case 1: ShouldNotReachHere(); break;
377   case 2: fun = OptoRuntime::multianewarray2_Java(); break;
378   case 3: fun = OptoRuntime::multianewarray3_Java(); break;
379   case 4: fun = OptoRuntime::multianewarray4_Java(); break;
380   case 5: fun = OptoRuntime::multianewarray5_Java(); break;
381   };
382   Node* c = NULL;
383 
384   if (fun != NULL) {
385     c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
386                           OptoRuntime::multianewarray_Type(ndimensions),
387                           fun, NULL, TypeRawPtr::BOTTOM,
388                           makecon(TypeKlassPtr::make(array_klass)),
389                           length[0], length[1], length[2],
390                           (ndimensions > 2) ? length[3] : NULL,
391                           (ndimensions > 3) ? length[4] : NULL);
392   } else {
393     // Create a java array for dimension sizes
394     Node* dims = NULL;
395     { PreserveReexecuteState preexecs(this);
396       inc_sp(ndimensions);
397       Node* dims_array_klass = makecon(TypeKlassPtr::make(ciArrayKlass::make(ciType::make(T_INT))));
398       dims = new_array(dims_array_klass, intcon(ndimensions), 0);
399 
400       // Fill-in it with values
401       for (j = 0; j < ndimensions; j++) {
402         Node *dims_elem = array_element_address(dims, intcon(j), T_INT);
403         store_to_memory(control(), dims_elem, length[j], T_INT, TypeAryPtr::INTS, MemNode::unordered);
404       }
405     }
406 
407     c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
408                           OptoRuntime::multianewarrayN_Type(),
409                           OptoRuntime::multianewarrayN_Java(), NULL, TypeRawPtr::BOTTOM,
410                           makecon(TypeKlassPtr::make(array_klass)),
411                           dims);
412   }
413   make_slow_call_ex(c, env()->Throwable_klass(), false);
414 
415   Node* res = _gvn.transform(new ProjNode(c, TypeFunc::Parms));
416 
417   const Type* type = TypeOopPtr::make_from_klass_raw(array_klass);
418 
419   // Improve the type:  We know it's not null, exact, and of a given length.
420   type = type->is_ptr()->cast_to_ptr_type(TypePtr::NotNull);
421   type = type->is_aryptr()->cast_to_exactness(true);
422 
423   const TypeInt* ltype = _gvn.find_int_type(length[0]);
424   if (ltype != NULL)
425     type = type->is_aryptr()->cast_to_size(ltype);
426 
427     // We cannot sharpen the nested sub-arrays, since the top level is mutable.
428 
429   Node* cast = _gvn.transform( new CheckCastPPNode(control(), res, type) );
430   push(cast);
431 
432   // Possible improvements:
433   // - Make a fast path for small multi-arrays.  (W/ implicit init. loops.)
434   // - Issue CastII against length[*] values, to TypeInt::POS.
435 }