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 "ci/ciInlineKlass.hpp"
26 #include "ci/ciSymbols.hpp"
27 #include "compiler/compileLog.hpp"
28 #include "oops/flatArrayKlass.hpp"
29 #include "oops/objArrayKlass.hpp"
30 #include "opto/addnode.hpp"
31 #include "opto/castnode.hpp"
32 #include "opto/inlinetypenode.hpp"
33 #include "opto/memnode.hpp"
34 #include "opto/mulnode.hpp"
35 #include "opto/parse.hpp"
36 #include "opto/rootnode.hpp"
37 #include "opto/runtime.hpp"
38 #include "runtime/sharedRuntime.hpp"
39
40 //------------------------------make_dtrace_method_entry_exit ----------------
41 // Dtrace -- record entry or exit of a method if compiled with dtrace support
42 void GraphKit::make_dtrace_method_entry_exit(ciMethod* method, bool is_entry) {
43 const TypeFunc *call_type = OptoRuntime::dtrace_method_entry_exit_Type();
44 address call_address = is_entry ? CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_entry) :
45 CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_exit);
46 const char *call_name = is_entry ? "dtrace_method_entry" : "dtrace_method_exit";
47
48 // Get base of thread-local storage area
49 Node* thread = _gvn.transform( new ThreadLocalNode() );
50
51 // Get method
52 const TypePtr* method_type = TypeMetadataPtr::make(method);
53 Node *method_node = _gvn.transform(ConNode::make(method_type));
54
55 kill_dead_locals();
56
57 // For some reason, this call reads only raw memory.
58 const TypePtr* raw_adr_type = TypeRawPtr::BOTTOM;
59 make_runtime_call(RC_LEAF | RC_NARROW_MEM,
60 call_type, call_address,
61 call_name, raw_adr_type,
62 thread, method_node);
63 }
64
65
66 //=============================================================================
67 //------------------------------do_checkcast-----------------------------------
68 void Parse::do_checkcast() {
69 bool will_link;
70 ciKlass* klass = iter().get_klass(will_link);
71 Node *obj = peek();
72
73 // Throw uncommon trap if class is not loaded or the value we are casting
74 // _from_ is not loaded, and value is not null. If the value _is_ null,
75 // then the checkcast does nothing.
76 const TypeOopPtr *tp = _gvn.type(obj)->isa_oopptr();
77 if (!will_link || (tp && !tp->is_loaded())) {
78 if (C->log() != nullptr) {
79 if (!will_link) {
80 C->log()->elem("assert_null reason='checkcast' klass='%d'",
81 C->log()->identify(klass));
82 }
83 if (tp && !tp->is_loaded()) {
84 // %%% Cannot happen?
85 ciKlass* klass = tp->unloaded_klass();
86 C->log()->elem("assert_null reason='checkcast source' klass='%d'",
87 C->log()->identify(klass));
88 }
89 }
90 null_assert(obj);
91 assert( stopped() || _gvn.type(peek())->higher_equal(TypePtr::NULL_PTR), "what's left behind is null" );
92 return;
93 }
94
95 Node* res = gen_checkcast(obj, makecon(TypeKlassPtr::make(klass, Type::trust_interfaces)));
96 if (stopped()) {
97 return;
98 }
99
100 // Pop from stack AFTER gen_checkcast because it can uncommon trap and
101 // the debug info has to be correct.
102 pop();
103 push(res);
104 }
105
106
107 //------------------------------do_instanceof----------------------------------
108 void Parse::do_instanceof() {
109 if (stopped()) return;
110 // We would like to return false if class is not loaded, emitting a
111 // dependency, but Java requires instanceof to load its operand.
112
113 // Throw uncommon trap if class is not loaded
114 bool will_link;
115 ciKlass* klass = iter().get_klass(will_link);
116
117 if (!will_link) {
118 if (C->log() != nullptr) {
119 C->log()->elem("assert_null reason='instanceof' klass='%d'",
120 C->log()->identify(klass));
121 }
122 null_assert(peek());
123 assert( stopped() || _gvn.type(peek())->higher_equal(TypePtr::NULL_PTR), "what's left behind is null" );
124 if (!stopped()) {
125 // The object is now known to be null.
126 // Shortcut the effect of gen_instanceof and return "false" directly.
127 pop(); // pop the null
128 push(_gvn.intcon(0)); // push false answer
129 }
130 return;
131 }
132
133 // Push the bool result back on stack
134 Node* res = gen_instanceof(peek(), makecon(TypeKlassPtr::make(klass, Type::trust_interfaces)), true);
135
136 // Pop from stack AFTER gen_instanceof because it can uncommon trap.
137 pop();
138 push(res);
139 }
140
141 //------------------------------array_store_check------------------------------
142 // pull array from stack and check that the store is valid
143 Node* Parse::array_store_check(Node*& adr, const Type*& elemtype) {
144 // Shorthand access to array store elements without popping them.
145 Node *obj = peek(0);
146 Node *idx = peek(1);
147 Node *ary = peek(2);
148
149 if (_gvn.type(obj) == TypePtr::NULL_PTR) {
150 // There's never a type check on null values.
151 // This cutout lets us avoid the uncommon_trap(Reason_array_check)
152 // below, which turns into a performance liability if the
153 // gen_checkcast folds up completely.
154 if (_gvn.type(ary)->is_aryptr()->is_null_free()) {
155 null_check(obj);
156 }
157 return obj;
158 }
159
160 // Extract the array klass type
161 Node* array_klass = load_object_klass(ary);
162 // Get the array klass
163 const TypeKlassPtr* tak = _gvn.type(array_klass)->is_klassptr();
164
165 // The type of array_klass is usually INexact array-of-oop. Heroically
166 // cast array_klass to EXACT array and uncommon-trap if the cast fails.
167 // Make constant out of the inexact array klass, but use it only if the cast
168 // succeeds.
169 if (MonomorphicArrayCheck && !tak->klass_is_exact()) {
170 // Make a constant out of the inexact array klass
171 const TypeAryKlassPtr* extak = nullptr;
172 const TypeOopPtr* ary_t = _gvn.type(ary)->is_oopptr();
173 ciKlass* ary_spec = ary_t->speculative_type();
174 Deoptimization::DeoptReason reason = Deoptimization::Reason_none;
175 // Try to cast the array to an exact type from profile data. First
176 // check the speculative type.
177 if (ary_spec != nullptr && !too_many_traps(Deoptimization::Reason_speculate_class_check)) {
178 extak = TypeKlassPtr::make(ary_spec)->is_aryklassptr();
179 reason = Deoptimization::Reason_speculate_class_check;
180 } else if (UseArrayLoadStoreProfile) {
181 // No speculative type: check profile data at this bci.
182 reason = Deoptimization::Reason_class_check;
183 if (!too_many_traps(reason)) {
184 ciKlass* array_type = nullptr;
185 ciKlass* element_type = nullptr;
186 ProfilePtrKind element_ptr = ProfileMaybeNull;
187 bool flat_array = true;
188 bool null_free_array = true;
189 method()->array_access_profiled_type(bci(), array_type, element_type, element_ptr, flat_array, null_free_array);
190 if (array_type != nullptr) {
191 extak = TypeKlassPtr::make(array_type)->is_aryklassptr();
192 }
193 }
194 } else if (!too_many_traps(Deoptimization::Reason_array_check) && tak->isa_aryklassptr()) {
195 // If the compiler has determined that the type of array 'ary' (represented
196 // by 'array_klass') is java/lang/Object, the compiler must not assume that
197 // the array 'ary' is monomorphic.
198 //
199 // If 'ary' were of type java/lang/Object, this arraystore would have to fail,
200 // because it is not possible to perform a arraystore into an object that is not
201 // a "proper" array.
202 //
203 // Therefore, let's obtain at runtime the type of 'ary' and check if we can still
204 // successfully perform the store.
205 //
206 // The implementation reasons for the condition are the following:
207 //
208 // java/lang/Object is the superclass of all arrays, but it is represented by the VM
209 // as an InstanceKlass. The checks generated by gen_checkcast() (see below) expect
210 // 'array_klass' to be ObjArrayKlass, which can result in invalid memory accesses.
211 //
212 // See issue JDK-8057622 for details.
213 extak = tak->cast_to_exactness(true)->is_aryklassptr();
214 reason = Deoptimization::Reason_array_check;
215 }
216 if (extak != nullptr && extak->exact_klass(true) != nullptr) {
217 Node* con = makecon(extak);
218 Node* cmp = _gvn.transform(new CmpPNode(array_klass, con));
219 Node* bol = _gvn.transform(new BoolNode(cmp, BoolTest::eq));
220 // Only do it if the check does not always pass/fail
221 if (!bol->is_Con()) {
222 { BuildCutout unless(this, bol, PROB_MAX);
223 uncommon_trap(reason,
224 Deoptimization::Action_maybe_recompile,
225 extak->exact_klass());
226 }
227 // Cast array klass to exactness
228 replace_in_map(array_klass, con);
229 array_klass = con;
230 Node* cast = _gvn.transform(new CheckCastPPNode(control(), ary, extak->as_instance_type()));
231 replace_in_map(ary, cast);
232 ary = cast;
233
234 // Recompute element type and address
235 const TypeAryPtr* arytype = _gvn.type(ary)->is_aryptr();
236 elemtype = arytype->elem();
237 adr = array_element_address(ary, idx, T_OBJECT, arytype->size(), control());
238
239 CompileLog* log = C->log();
240 if (log != nullptr) {
241 log->elem("cast_up reason='monomorphic_array' from='%d' to='(exact)'",
242 log->identify(extak->exact_klass()));
243 }
244 }
245 }
246 }
247
248 // Come here for polymorphic array klasses
249
250 // Extract the array element class
251 int element_klass_offset = in_bytes(ArrayKlass::element_klass_offset());
252 Node* p2 = basic_plus_adr(array_klass, array_klass, element_klass_offset);
253 Node* a_e_klass = _gvn.transform(LoadKlassNode::make(_gvn, immutable_memory(), p2, tak));
254
255 // If we statically know that this is an inline type array, use precise element klass for checkcast
256 const TypeAryPtr* arytype = _gvn.type(ary)->is_aryptr();
257 const TypePtr* elem_ptr = elemtype->make_ptr();
258 bool null_free = arytype->is_null_free();
259 if (elem_ptr->is_inlinetypeptr()) {
260 // We statically know that this is an inline type array, use precise klass ptr
261 a_e_klass = makecon(TypeKlassPtr::make(elemtype->inline_klass()));
262 }
263 #ifdef ASSERT
264 if (!StressReflectiveCode && array_klass->is_Con() != a_e_klass->is_Con()) {
265 // When the element type is exact, the array type also needs to be exact. There is one exception, though:
266 // Nullable arrays are not exact because the null-free array is a subtype while the element type being a
267 // concrete value class (i.e. final) is always exact.
268 assert(!array_klass->is_Con() && a_e_klass->is_Con() && elem_ptr->is_inlinetypeptr() && !null_free,
269 "a constant element type either matches a constant array type or a non-constant nullable value class array");
270 }
271
272 // If the element type is exact, the array can be null-free (i.e. the element type is NotNull) if:
273 // - The elements are inline types
274 // - The array is from an autobox cache.
275 // If the element type is inexact, it could represent multiple null-free arrays. Since autobox cache arrays
276 // are local to very few cache classes and are only used in the valueOf() methods, they are always exact and are not
277 // merged or hidden behind super types. Therefore, an inexact null-free array always represents some kind of
278 // inline type array - either of an abstract value class or Object.
279 if (null_free) {
280 ciKlass* klass = elem_ptr->is_instptr()->instance_klass();
281 if (klass->exact_klass()) {
282 assert(elem_ptr->is_inlinetypeptr() || arytype->is_autobox_cache(), "elements must be inline type or autobox cache");
283 } else {
284 assert(!arytype->is_autobox_cache() && elem_ptr->can_be_inline_type() &&
285 (klass->is_java_lang_Object() || klass->is_abstract()), "cannot have inexact non-inline type elements");
286 }
287 }
288 #endif // ASSERT
289
290 // Check (the hard way) and throw if not a subklass.
291 return gen_checkcast(obj, a_e_klass, nullptr, null_free);
292 }
293
294
295 //------------------------------do_new-----------------------------------------
296 void Parse::do_new() {
297 kill_dead_locals();
298
299 bool will_link;
300 ciInstanceKlass* klass = iter().get_klass(will_link)->as_instance_klass();
301 assert(will_link, "_new: typeflow responsibility");
302
303 // Should throw an InstantiationError?
304 if (klass->is_abstract() || klass->is_interface() ||
305 klass->name() == ciSymbols::java_lang_Class() ||
306 iter().is_unresolved_klass()) {
307 uncommon_trap(Deoptimization::Reason_unhandled,
308 Deoptimization::Action_none,
309 klass);
310 return;
311 }
312
313 if (C->needs_clinit_barrier(klass, method())) {
314 clinit_barrier(klass, method());
315 if (stopped()) return;
316 }
317
318 if (klass->is_inlinetype()) {
319 push(InlineTypeNode::make_all_zero(_gvn, klass->as_inline_klass(), /* is_larval */ true));
320 return;
321 }
322
323 Node* kls = makecon(TypeKlassPtr::make(klass));
324 Node* obj = new_instance(kls);
325
326 // Push resultant oop onto stack
327 push(obj);
328
329 // Keep track of whether opportunities exist for StringBuilder
330 // optimizations.
331 if (OptimizeStringConcat &&
332 (klass == C->env()->StringBuilder_klass() ||
333 klass == C->env()->StringBuffer_klass())) {
334 C->set_has_stringbuilder(true);
335 }
336
337 // Keep track of boxed values for EliminateAutoBox optimizations.
338 if (C->eliminate_boxing() && klass->is_box_klass()) {
339 C->set_has_boxed_value(true);
340 }
341 }
342
343 #ifndef PRODUCT
344 //------------------------------dump_map_adr_mem-------------------------------
345 // Debug dump of the mapping from address types to MergeMemNode indices.
346 void Parse::dump_map_adr_mem() const {
347 tty->print_cr("--- Mapping from address types to memory Nodes ---");
348 MergeMemNode *mem = map() == nullptr ? nullptr : (map()->memory()->is_MergeMem() ?
349 map()->memory()->as_MergeMem() : nullptr);
350 for (uint i = 0; i < (uint)C->num_alias_types(); i++) {
351 C->alias_type(i)->print_on(tty);
352 tty->print("\t");
353 // Node mapping, if any
354 if (mem && i < mem->req() && mem->in(i) && mem->in(i) != mem->empty_memory()) {
355 mem->in(i)->dump();
356 } else {
357 tty->cr();
358 }
359 }
360 }
361
362 #endif