1 /*
  2  * Copyright (c) 1998, 2025, 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 "compiler/compileLog.hpp"
 26 #include "interpreter/linkResolver.hpp"
 27 #include "memory/universe.hpp"
 28 #include "oops/objArrayKlass.hpp"
 29 #include "opto/addnode.hpp"
 30 #include "opto/castnode.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 void Parse::do_field_access(bool is_get, bool is_field) {
 43   bool will_link;
 44   ciField* field = iter().get_field(will_link);
 45   assert(will_link, "getfield: typeflow responsibility");
 46 
 47   ciInstanceKlass* field_holder = field->holder();
 48 
 49   if (is_field == field->is_static()) {
 50     // Interpreter will throw java_lang_IncompatibleClassChangeError
 51     // Check this before allowing <clinit> methods to access static fields
 52     uncommon_trap(Deoptimization::Reason_unhandled,
 53                   Deoptimization::Action_none);
 54     return;
 55   }
 56 
 57   // Deoptimize on putfield writes to call site target field outside of CallSite ctor.
 58   if (!is_get && field->is_call_site_target() &&
 59       !(method()->holder() == field_holder && method()->is_object_initializer())) {
 60     uncommon_trap(Deoptimization::Reason_unhandled,
 61                   Deoptimization::Action_reinterpret,
 62                   nullptr, "put to call site target field");
 63     return;
 64   }
 65 
 66   if (C->needs_clinit_barrier(field, method())) {
 67     clinit_barrier(field_holder, method());
 68     if (stopped())  return;
 69   }
 70 
 71   assert(field->will_link(method(), bc()), "getfield: typeflow responsibility");
 72 
 73   // Note:  We do not check for an unloaded field type here any more.
 74 
 75   // Generate code for the object pointer.
 76   Node* obj;
 77   if (is_field) {
 78     int obj_depth = is_get ? 0 : field->type()->size();
 79     obj = null_check(peek(obj_depth));
 80     // Compile-time detect of null-exception?
 81     if (stopped())  return;
 82 
 83 #ifdef ASSERT
 84     const TypeInstPtr *tjp = TypeInstPtr::make(TypePtr::NotNull, iter().get_declared_field_holder());
 85     assert(_gvn.type(obj)->higher_equal(tjp), "cast_up is no longer needed");
 86 #endif
 87 
 88     if (is_get) {
 89       (void) pop();  // pop receiver before getting
 90       do_get_xxx(obj, field, is_field);
 91     } else {
 92       do_put_xxx(obj, field, is_field);
 93       (void) pop();  // pop receiver after putting
 94     }
 95   } else {
 96     const TypeInstPtr* tip = TypeInstPtr::make(field_holder->java_mirror());
 97     obj = _gvn.makecon(tip);
 98     if (is_get) {
 99       do_get_xxx(obj, field, is_field);
100     } else {
101       do_put_xxx(obj, field, is_field);
102     }
103   }
104 }
105 
106 
107 void Parse::do_get_xxx(Node* obj, ciField* field, bool is_field) {
108   BasicType bt = field->layout_type();
109 
110   // Does this field have a constant value?  If so, just push the value.
111   if (field->is_constant() &&
112       // Keep consistent with types found by ciTypeFlow: for an
113       // unloaded field type, ciTypeFlow::StateVector::do_getstatic()
114       // speculates the field is null. The code in the rest of this
115       // method does the same. We must not bypass it and use a non
116       // null constant here.
117       (bt != T_OBJECT || field->type()->is_loaded())) {
118     // final or stable field
119     Node* con = make_constant_from_field(field, obj);
120     if (con != nullptr) {
121       push_node(field->layout_type(), con);
122       return;
123     }
124   }
125 
126   ciType* field_klass = field->type();
127   bool is_vol = field->is_volatile();
128 
129   // Compute address and memory type.
130   int offset = field->offset_in_bytes();
131   const TypePtr* adr_type = C->alias_type(field)->adr_type();
132   Node *adr = basic_plus_adr(obj, obj, offset);
133   assert(C->get_alias_index(adr_type) == C->get_alias_index(_gvn.type(adr)->isa_ptr()),
134     "slice of address and input slice don't match");
135 
136   // Build the resultant type of the load
137   const Type *type;
138 
139   bool must_assert_null = false;
140 
141   DecoratorSet decorators = IN_HEAP;
142   decorators |= is_vol ? MO_SEQ_CST : MO_UNORDERED;
143 
144   bool is_obj = is_reference_type(bt);
145 
146   if (is_obj) {
147     if (!field->type()->is_loaded()) {
148       type = TypeInstPtr::BOTTOM;
149       must_assert_null = true;
150     } else if (field->is_static_constant()) {
151       // This can happen if the constant oop is non-perm.
152       ciObject* con = field->constant_value().as_object();
153       // Do not "join" in the previous type; it doesn't add value,
154       // and may yield a vacuous result if the field is of interface type.
155       if (con->is_null_object()) {
156         type = TypePtr::NULL_PTR;
157       } else {
158         type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
159       }
160       assert(type != nullptr, "field singleton type must be consistent");
161     } else {
162       type = TypeOopPtr::make_from_klass(field_klass->as_klass());
163     }
164   } else {
165     type = Type::get_const_basic_type(bt);
166   }
167 
168   Node* ld = access_load_at(obj, adr, adr_type, type, bt, decorators);
169 
170   // Adjust Java stack
171   if (type2size[bt] == 1)
172     push(ld);
173   else
174     push_pair(ld);
175 
176   if (must_assert_null) {
177     // Do not take a trap here.  It's possible that the program
178     // will never load the field's class, and will happily see
179     // null values in this field forever.  Don't stumble into a
180     // trap for such a program, or we might get a long series
181     // of useless recompilations.  (Or, we might load a class
182     // which should not be loaded.)  If we ever see a non-null
183     // value, we will then trap and recompile.  (The trap will
184     // not need to mention the class index, since the class will
185     // already have been loaded if we ever see a non-null value.)
186     // uncommon_trap(iter().get_field_signature_index());
187     if (PrintOpto && (Verbose || WizardMode)) {
188       method()->print_name(); tty->print_cr(" asserting nullness of field at bci: %d", bci());
189     }
190     if (C->log() != nullptr) {
191       C->log()->elem("assert_null reason='field' klass='%d'",
192                      C->log()->identify(field->type()));
193     }
194     // If there is going to be a trap, put it at the next bytecode:
195     set_bci(iter().next_bci());
196     null_assert(peek());
197     set_bci(iter().cur_bci()); // put it back
198   }
199 }
200 
201 void Parse::do_put_xxx(Node* obj, ciField* field, bool is_field) {
202   bool is_vol = field->is_volatile();
203 
204   // Compute address and memory type.
205   int offset = field->offset_in_bytes();
206   const TypePtr* adr_type = C->alias_type(field)->adr_type();
207   Node* adr = basic_plus_adr(obj, obj, offset);
208   assert(C->get_alias_index(adr_type) == C->get_alias_index(_gvn.type(adr)->isa_ptr()),
209     "slice of address and input slice don't match");
210   BasicType bt = field->layout_type();
211   // Value to be stored
212   Node* val = type2size[bt] == 1 ? pop() : pop_pair();
213 
214   DecoratorSet decorators = IN_HEAP;
215   decorators |= is_vol ? MO_SEQ_CST : MO_UNORDERED;
216 
217   bool is_obj = is_reference_type(bt);
218 
219   // Store the value.
220   const Type* field_type;
221   if (!field->type()->is_loaded()) {
222     field_type = TypeInstPtr::BOTTOM;
223   } else {
224     if (is_obj) {
225       field_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
226     } else {
227       field_type = Type::BOTTOM;
228     }
229   }
230   access_store_at(obj, adr, adr_type, val, field_type, bt, decorators);
231 
232   if (is_field) {
233     // Remember we wrote a volatile field.
234     // For not multiple copy atomic cpu (ppc64) a barrier should be issued
235     // in constructors which have such stores. See do_exits() in parse1.cpp.
236     if (is_vol) {
237       set_wrote_volatile(true);
238     }
239     set_wrote_fields(true);
240 
241     // If the field is final, the rules of Java say we are in <init> or <clinit>.
242     // If the field is @Stable, we can be in any method, but we only care about
243     // constructors at this point.
244     //
245     // Note the presence of writes to final/@Stable non-static fields, so that we
246     // can insert a memory barrier later on to keep the writes from floating
247     // out of the constructor.
248     if (field->is_final() || field->is_stable()) {
249       if (field->is_final()) {
250         set_wrote_final(true);
251       }
252       if (field->is_stable()) {
253         set_wrote_stable(true);
254       }
255       if (AllocateNode::Ideal_allocation(obj) != nullptr) {
256         // Preserve allocation ptr to create precedent edge to it in membar
257         // generated on exit from constructor.
258         set_alloc_with_final_or_stable(obj);
259       }
260     }
261   }
262 }
263 
264 //=============================================================================
265 void Parse::do_anewarray() {
266   bool will_link;
267   ciKlass* klass = iter().get_klass(will_link);
268 
269   // Uncommon Trap when class that array contains is not loaded
270   // we need the loaded class for the rest of graph; do not
271   // initialize the container class (see Java spec)!!!
272   assert(will_link, "anewarray: typeflow responsibility");
273 
274   ciObjArrayKlass* array_klass = ciObjArrayKlass::make(klass);
275   // Check that array_klass object is loaded
276   if (!array_klass->is_loaded()) {
277     // Generate uncommon_trap for unloaded array_class
278     uncommon_trap(Deoptimization::Reason_unloaded,
279                   Deoptimization::Action_reinterpret,
280                   array_klass);
281     return;
282   }
283 
284   kill_dead_locals();
285 
286   const TypeKlassPtr* array_klass_type = TypeKlassPtr::make(array_klass, Type::trust_interfaces);
287   Node* count_val = pop();
288   Node* obj = new_array(makecon(array_klass_type), count_val, 1);
289   push(obj);
290 }
291 
292 
293 void Parse::do_newarray(BasicType elem_type) {
294   kill_dead_locals();
295 
296   Node*   count_val = pop();
297   const TypeKlassPtr* array_klass = TypeKlassPtr::make(ciTypeArrayKlass::make(elem_type));
298   Node*   obj = new_array(makecon(array_klass), count_val, 1);
299   // Push resultant oop onto stack
300   push(obj);
301 }
302 
303 // Expand simple expressions like new int[3][5] and new Object[2][nonConLen].
304 // Also handle the degenerate 1-dimensional case of anewarray.
305 Node* Parse::expand_multianewarray(ciArrayKlass* array_klass, Node* *lengths, int ndimensions, int nargs) {
306   Node* length = lengths[0];
307   assert(length != nullptr, "");
308   Node* array = new_array(makecon(TypeKlassPtr::make(array_klass, Type::trust_interfaces)), length, nargs);
309   if (ndimensions > 1) {
310     jint length_con = find_int_con(length, -1);
311     guarantee(length_con >= 0, "non-constant multianewarray");
312     ciArrayKlass* array_klass_1 = array_klass->as_obj_array_klass()->element_klass()->as_array_klass();
313     const TypePtr* adr_type = TypeAryPtr::OOPS;
314     const TypeOopPtr*    elemtype = _gvn.type(array)->is_aryptr()->elem()->make_oopptr();
315     const intptr_t header   = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
316     for (jint i = 0; i < length_con; i++) {
317       Node*    elem   = expand_multianewarray(array_klass_1, &lengths[1], ndimensions-1, nargs);
318       intptr_t offset = header + ((intptr_t)i << LogBytesPerHeapOop);
319       Node*    eaddr  = basic_plus_adr(array, offset);
320       access_store_at(array, eaddr, adr_type, elem, elemtype, T_OBJECT, IN_HEAP | IS_ARRAY);
321     }
322   }
323   return array;
324 }
325 
326 void Parse::do_multianewarray() {
327   int ndimensions = iter().get_dimensions();
328 
329   // the m-dimensional array
330   bool will_link;
331   ciArrayKlass* array_klass = iter().get_klass(will_link)->as_array_klass();
332   assert(will_link, "multianewarray: typeflow responsibility");
333 
334   // Note:  Array classes are always initialized; no is_initialized check.
335 
336   kill_dead_locals();
337 
338   // get the lengths from the stack (first dimension is on top)
339   Node** length = NEW_RESOURCE_ARRAY(Node*, ndimensions + 1);
340   length[ndimensions] = nullptr;  // terminating null for make_runtime_call
341   int j;
342   for (j = ndimensions-1; j >= 0 ; j--) length[j] = pop();
343 
344   // The original expression was of this form: new T[length0][length1]...
345   // It is often the case that the lengths are small (except the last).
346   // If that happens, use the fast 1-d creator a constant number of times.
347   const int expand_limit = MIN2((int)MultiArrayExpandLimit, 100);
348   int64_t expand_count = 1;        // count of allocations in the expansion
349   int64_t expand_fanout = 1;       // running total fanout
350   for (j = 0; j < ndimensions-1; j++) {
351     int dim_con = find_int_con(length[j], -1);
352     // To prevent overflow, we use 64-bit values.  Alternatively,
353     // we could clamp dim_con like so:
354     // dim_con = MIN2(dim_con, expand_limit);
355     expand_fanout *= dim_con;
356     expand_count  += expand_fanout; // count the level-J sub-arrays
357     if (dim_con <= 0
358         || dim_con > expand_limit
359         || expand_count > expand_limit) {
360       expand_count = 0;
361       break;
362     }
363   }
364 
365   // Can use multianewarray instead of [a]newarray if only one dimension,
366   // or if all non-final dimensions are small constants.
367   if (ndimensions == 1 || (1 <= expand_count && expand_count <= expand_limit)) {
368     Node* obj = nullptr;
369     // Set the original stack and the reexecute bit for the interpreter
370     // to reexecute the multianewarray bytecode if deoptimization happens.
371     // Do it unconditionally even for one dimension multianewarray.
372     // Note: the reexecute bit will be set in GraphKit::add_safepoint_edges()
373     // when AllocateArray node for newarray is created.
374     { PreserveReexecuteState preexecs(this);
375       inc_sp(ndimensions);
376       // Pass 0 as nargs since uncommon trap code does not need to restore stack.
377       obj = expand_multianewarray(array_klass, &length[0], ndimensions, 0);
378     } //original reexecute and sp are set back here
379     push(obj);
380     return;
381   }
382 
383   address fun = nullptr;
384   switch (ndimensions) {
385   case 1: ShouldNotReachHere(); break;
386   case 2: fun = OptoRuntime::multianewarray2_Java(); break;
387   case 3: fun = OptoRuntime::multianewarray3_Java(); break;
388   case 4: fun = OptoRuntime::multianewarray4_Java(); break;
389   case 5: fun = OptoRuntime::multianewarray5_Java(); break;
390   };
391   Node* c = nullptr;
392 
393   if (fun != nullptr) {
394     c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
395                           OptoRuntime::multianewarray_Type(ndimensions),
396                           fun, nullptr, TypeRawPtr::BOTTOM,
397                           makecon(TypeKlassPtr::make(array_klass, Type::trust_interfaces)),
398                           length[0], length[1], length[2],
399                           (ndimensions > 2) ? length[3] : nullptr,
400                           (ndimensions > 3) ? length[4] : nullptr);
401   } else {
402     // Create a java array for dimension sizes
403     Node* dims = nullptr;
404     { PreserveReexecuteState preexecs(this);
405       inc_sp(ndimensions);
406       Node* dims_array_klass = makecon(TypeKlassPtr::make(ciArrayKlass::make(ciType::make(T_INT))));
407       dims = new_array(dims_array_klass, intcon(ndimensions), 0);
408 
409       // Fill-in it with values
410       for (j = 0; j < ndimensions; j++) {
411         Node *dims_elem = array_element_address(dims, intcon(j), T_INT);
412         store_to_memory(control(), dims_elem, length[j], T_INT, MemNode::unordered);
413       }
414     }
415 
416     c = make_runtime_call(RC_NO_LEAF | RC_NO_IO,
417                           OptoRuntime::multianewarrayN_Type(),
418                           OptoRuntime::multianewarrayN_Java(), nullptr, TypeRawPtr::BOTTOM,
419                           makecon(TypeKlassPtr::make(array_klass, Type::trust_interfaces)),
420                           dims);
421   }
422   make_slow_call_ex(c, env()->Throwable_klass(), false);
423 
424   Node* res = _gvn.transform(new ProjNode(c, TypeFunc::Parms));
425 
426   const Type* type = TypeOopPtr::make_from_klass_raw(array_klass, Type::trust_interfaces);
427 
428   // Improve the type:  We know it's not null, exact, and of a given length.
429   type = type->is_ptr()->cast_to_ptr_type(TypePtr::NotNull);
430   type = type->is_aryptr()->cast_to_exactness(true);
431 
432   const TypeInt* ltype = _gvn.find_int_type(length[0]);
433   if (ltype != nullptr)
434     type = type->is_aryptr()->cast_to_size(ltype);
435 
436     // We cannot sharpen the nested sub-arrays, since the top level is mutable.
437 
438   Node* cast = _gvn.transform( new CheckCastPPNode(control(), res, type) );
439   push(cast);
440 
441   // Possible improvements:
442   // - Make a fast path for small multi-arrays.  (W/ implicit init. loops.)
443   // - Issue CastII against length[*] values, to TypeInt::POS.
444 }