1 /*
2 * Copyright (c) 1998, 2015, 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 *
48 case JVM_CONSTANT_Methodref : // fall through
49 add_cp_cache_entry(i);
50 break;
51 case JVM_CONSTANT_String:
52 case JVM_CONSTANT_MethodHandle : // fall through
53 case JVM_CONSTANT_MethodType : // fall through
54 add_resolved_references_entry(i);
55 break;
56 case JVM_CONSTANT_Utf8:
57 if (_pool->symbol_at(i) == vmSymbols::java_lang_invoke_MethodHandle() ||
58 _pool->symbol_at(i) == vmSymbols::java_lang_invoke_VarHandle()) {
59 saw_mh_symbol = true;
60 }
61 break;
62 }
63 }
64
65 // Record limits of resolved reference map for constant pool cache indices
66 record_map_limits();
67
68 guarantee((int)_cp_cache_map.length()-1 <= (int)((u2)-1),
69 "all cp cache indexes fit in a u2");
70
71 if (saw_mh_symbol)
72 _method_handle_invokers.initialize(length, (int)0);
73 }
74
75 // Unrewrite the bytecodes if an error occurs.
76 void Rewriter::restore_bytecodes() {
77 int len = _methods->length();
78 bool invokespecial_error = false;
79
80 for (int i = len-1; i >= 0; i--) {
81 Method* method = _methods->at(i);
82 scan_method(method, true, &invokespecial_error);
83 assert(!invokespecial_error, "reversing should not get an invokespecial error");
84 }
85 }
86
87 // Creates a constant pool cache given a CPC map
88 void Rewriter::make_constant_pool_cache(TRAPS) {
89 ClassLoaderData* loader_data = _pool->pool_holder()->class_loader_data();
90 ConstantPoolCache* cache =
91 ConstantPoolCache::allocate(loader_data, _cp_cache_map,
92 _invokedynamic_cp_cache_map,
176 }
177 Bytes::put_native_u2(p, cache_index);
178 } else {
179 rewrite_member_reference(bcp, offset, reverse);
180 }
181 } else {
182 rewrite_member_reference(bcp, offset, reverse);
183 }
184 }
185
186
187 // Adjust the invocation bytecode for a signature-polymorphic method (MethodHandle.invoke, etc.)
188 void Rewriter::maybe_rewrite_invokehandle(address opc, int cp_index, int cache_index, bool reverse) {
189 if (!reverse) {
190 if ((*opc) == (u1)Bytecodes::_invokevirtual ||
191 // allow invokespecial as an alias, although it would be very odd:
192 (*opc) == (u1)Bytecodes::_invokespecial) {
193 assert(_pool->tag_at(cp_index).is_method(), "wrong index");
194 // Determine whether this is a signature-polymorphic method.
195 if (cp_index >= _method_handle_invokers.length()) return;
196 int status = _method_handle_invokers[cp_index];
197 assert(status >= -1 && status <= 1, "oob tri-state");
198 if (status == 0) {
199 if (_pool->klass_ref_at_noresolve(cp_index) == vmSymbols::java_lang_invoke_MethodHandle() &&
200 MethodHandles::is_signature_polymorphic_name(SystemDictionary::MethodHandle_klass(),
201 _pool->name_ref_at(cp_index))) {
202 // we may need a resolved_refs entry for the appendix
203 add_invokedynamic_resolved_references_entries(cp_index, cache_index);
204 status = +1;
205 } else if (_pool->klass_ref_at_noresolve(cp_index) == vmSymbols::java_lang_invoke_VarHandle() &&
206 MethodHandles::is_signature_polymorphic_name(SystemDictionary::VarHandle_klass(),
207 _pool->name_ref_at(cp_index))) {
208 // we may need a resolved_refs entry for the appendix
209 add_invokedynamic_resolved_references_entries(cp_index, cache_index);
210 status = +1;
211 } else {
212 status = -1;
213 }
214 _method_handle_invokers[cp_index] = status;
215 }
216 // We use a special internal bytecode for such methods (if non-static).
217 // The basic reason for this is that such methods need an extra "appendix" argument
218 // to transmit the call site's intended call type.
219 if (status > 0) {
220 (*opc) = (u1)Bytecodes::_invokehandle;
221 }
222 }
223 } else {
224 // Do not need to look at cp_index.
225 if ((*opc) == (u1)Bytecodes::_invokehandle) {
226 (*opc) = (u1)Bytecodes::_invokevirtual;
227 // Ignore corner case of original _invokespecial instruction.
228 // This is safe because (a) the signature polymorphic method was final, and
229 // (b) the implementation of MethodHandle will not call invokespecial on it.
230 }
231 }
232 }
233
234
270
271 void Rewriter::patch_invokedynamic_bytecodes() {
272 // If the end of the cp_cache is the same as after initializing with the
273 // cpool, nothing needs to be done. Invokedynamic bytecodes are at the
274 // correct offsets. ie. no invokespecials added
275 int delta = cp_cache_delta();
276 if (delta > 0) {
277 int length = _patch_invokedynamic_bcps->length();
278 assert(length == _patch_invokedynamic_refs->length(),
279 "lengths should match");
280 for (int i = 0; i < length; i++) {
281 address p = _patch_invokedynamic_bcps->at(i);
282 int cache_index = ConstantPool::decode_invokedynamic_index(
283 Bytes::get_native_u4(p));
284 Bytes::put_native_u4(p, ConstantPool::encode_invokedynamic_index(cache_index + delta));
285
286 // invokedynamic resolved references map also points to cp cache and must
287 // add delta to each.
288 int resolved_index = _patch_invokedynamic_refs->at(i);
289 for (int entry = 0; entry < ConstantPoolCacheEntry::_indy_resolved_references_entries; entry++) {
290 assert(_invokedynamic_references_map[resolved_index+entry] == cache_index,
291 "should be the same index");
292 _invokedynamic_references_map.at_put(resolved_index+entry,
293 cache_index + delta);
294 }
295 }
296 }
297 }
298
299
300 // Rewrite some ldc bytecodes to _fast_aldc
301 void Rewriter::maybe_rewrite_ldc(address bcp, int offset, bool is_wide,
302 bool reverse) {
303 if (!reverse) {
304 assert((*bcp) == (is_wide ? Bytecodes::_ldc_w : Bytecodes::_ldc), "not ldc bytecode");
305 address p = bcp + offset;
306 int cp_index = is_wide ? Bytes::get_Java_u2(p) : (u1)(*p);
307 constantTag tag = _pool->tag_at(cp_index).value();
308 if (tag.is_method_handle() || tag.is_method_type() || tag.is_string()) {
309 int ref_index = cp_entry_to_resolved_references(cp_index);
310 if (is_wide) {
503 }
504 }
505
506 // May have to fix invokedynamic bytecodes if invokestatic/InterfaceMethodref
507 // entries had to be added.
508 patch_invokedynamic_bytecodes();
509 }
510
511 void Rewriter::rewrite(instanceKlassHandle klass, TRAPS) {
512 if (!DumpSharedSpaces) {
513 assert(!MetaspaceShared::is_in_shared_space(klass()), "archive methods must not be rewritten at run time");
514 }
515 ResourceMark rm(THREAD);
516 Rewriter rw(klass, klass->constants(), klass->methods(), CHECK);
517 // (That's all, folks.)
518 }
519
520 Rewriter::Rewriter(instanceKlassHandle klass, const constantPoolHandle& cpool, Array<Method*>* methods, TRAPS)
521 : _klass(klass),
522 _pool(cpool),
523 _methods(methods)
524 {
525
526 // Rewrite bytecodes - exception here exits.
527 rewrite_bytecodes(CHECK);
528
529 // Stress restoring bytecodes
530 if (StressRewriter) {
531 restore_bytecodes();
532 rewrite_bytecodes(CHECK);
533 }
534
535 // allocate constant pool cache, now that we've seen all the bytecodes
536 make_constant_pool_cache(THREAD);
537
538 // Restore bytecodes to their unrewritten state if there are exceptions
539 // rewriting bytecodes or allocating the cpCache
540 if (HAS_PENDING_EXCEPTION) {
541 restore_bytecodes();
542 return;
543 }
|
1 /*
2 * Copyright (c) 1998, 2016, 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 *
48 case JVM_CONSTANT_Methodref : // fall through
49 add_cp_cache_entry(i);
50 break;
51 case JVM_CONSTANT_String:
52 case JVM_CONSTANT_MethodHandle : // fall through
53 case JVM_CONSTANT_MethodType : // fall through
54 add_resolved_references_entry(i);
55 break;
56 case JVM_CONSTANT_Utf8:
57 if (_pool->symbol_at(i) == vmSymbols::java_lang_invoke_MethodHandle() ||
58 _pool->symbol_at(i) == vmSymbols::java_lang_invoke_VarHandle()) {
59 saw_mh_symbol = true;
60 }
61 break;
62 }
63 }
64
65 // Record limits of resolved reference map for constant pool cache indices
66 record_map_limits();
67
68 guarantee((int) _cp_cache_map.length() - 1 <= (int) ((u2)-1),
69 "all cp cache indexes fit in a u2");
70
71 if (saw_mh_symbol) {
72 _method_handle_invokers.at_grow(length, 0);
73 }
74 }
75
76 // Unrewrite the bytecodes if an error occurs.
77 void Rewriter::restore_bytecodes() {
78 int len = _methods->length();
79 bool invokespecial_error = false;
80
81 for (int i = len-1; i >= 0; i--) {
82 Method* method = _methods->at(i);
83 scan_method(method, true, &invokespecial_error);
84 assert(!invokespecial_error, "reversing should not get an invokespecial error");
85 }
86 }
87
88 // Creates a constant pool cache given a CPC map
89 void Rewriter::make_constant_pool_cache(TRAPS) {
90 ClassLoaderData* loader_data = _pool->pool_holder()->class_loader_data();
91 ConstantPoolCache* cache =
92 ConstantPoolCache::allocate(loader_data, _cp_cache_map,
93 _invokedynamic_cp_cache_map,
177 }
178 Bytes::put_native_u2(p, cache_index);
179 } else {
180 rewrite_member_reference(bcp, offset, reverse);
181 }
182 } else {
183 rewrite_member_reference(bcp, offset, reverse);
184 }
185 }
186
187
188 // Adjust the invocation bytecode for a signature-polymorphic method (MethodHandle.invoke, etc.)
189 void Rewriter::maybe_rewrite_invokehandle(address opc, int cp_index, int cache_index, bool reverse) {
190 if (!reverse) {
191 if ((*opc) == (u1)Bytecodes::_invokevirtual ||
192 // allow invokespecial as an alias, although it would be very odd:
193 (*opc) == (u1)Bytecodes::_invokespecial) {
194 assert(_pool->tag_at(cp_index).is_method(), "wrong index");
195 // Determine whether this is a signature-polymorphic method.
196 if (cp_index >= _method_handle_invokers.length()) return;
197 int status = _method_handle_invokers.at(cp_index);
198 assert(status >= -1 && status <= 1, "oob tri-state");
199 if (status == 0) {
200 if (_pool->klass_ref_at_noresolve(cp_index) == vmSymbols::java_lang_invoke_MethodHandle() &&
201 MethodHandles::is_signature_polymorphic_name(SystemDictionary::MethodHandle_klass(),
202 _pool->name_ref_at(cp_index))) {
203 // we may need a resolved_refs entry for the appendix
204 add_invokedynamic_resolved_references_entries(cp_index, cache_index);
205 status = +1;
206 } else if (_pool->klass_ref_at_noresolve(cp_index) == vmSymbols::java_lang_invoke_VarHandle() &&
207 MethodHandles::is_signature_polymorphic_name(SystemDictionary::VarHandle_klass(),
208 _pool->name_ref_at(cp_index))) {
209 // we may need a resolved_refs entry for the appendix
210 add_invokedynamic_resolved_references_entries(cp_index, cache_index);
211 status = +1;
212 } else {
213 status = -1;
214 }
215 _method_handle_invokers.at(cp_index) = status;
216 }
217 // We use a special internal bytecode for such methods (if non-static).
218 // The basic reason for this is that such methods need an extra "appendix" argument
219 // to transmit the call site's intended call type.
220 if (status > 0) {
221 (*opc) = (u1)Bytecodes::_invokehandle;
222 }
223 }
224 } else {
225 // Do not need to look at cp_index.
226 if ((*opc) == (u1)Bytecodes::_invokehandle) {
227 (*opc) = (u1)Bytecodes::_invokevirtual;
228 // Ignore corner case of original _invokespecial instruction.
229 // This is safe because (a) the signature polymorphic method was final, and
230 // (b) the implementation of MethodHandle will not call invokespecial on it.
231 }
232 }
233 }
234
235
271
272 void Rewriter::patch_invokedynamic_bytecodes() {
273 // If the end of the cp_cache is the same as after initializing with the
274 // cpool, nothing needs to be done. Invokedynamic bytecodes are at the
275 // correct offsets. ie. no invokespecials added
276 int delta = cp_cache_delta();
277 if (delta > 0) {
278 int length = _patch_invokedynamic_bcps->length();
279 assert(length == _patch_invokedynamic_refs->length(),
280 "lengths should match");
281 for (int i = 0; i < length; i++) {
282 address p = _patch_invokedynamic_bcps->at(i);
283 int cache_index = ConstantPool::decode_invokedynamic_index(
284 Bytes::get_native_u4(p));
285 Bytes::put_native_u4(p, ConstantPool::encode_invokedynamic_index(cache_index + delta));
286
287 // invokedynamic resolved references map also points to cp cache and must
288 // add delta to each.
289 int resolved_index = _patch_invokedynamic_refs->at(i);
290 for (int entry = 0; entry < ConstantPoolCacheEntry::_indy_resolved_references_entries; entry++) {
291 assert(_invokedynamic_references_map.at(resolved_index + entry) == cache_index,
292 "should be the same index");
293 _invokedynamic_references_map.at_put(resolved_index+entry,
294 cache_index + delta);
295 }
296 }
297 }
298 }
299
300
301 // Rewrite some ldc bytecodes to _fast_aldc
302 void Rewriter::maybe_rewrite_ldc(address bcp, int offset, bool is_wide,
303 bool reverse) {
304 if (!reverse) {
305 assert((*bcp) == (is_wide ? Bytecodes::_ldc_w : Bytecodes::_ldc), "not ldc bytecode");
306 address p = bcp + offset;
307 int cp_index = is_wide ? Bytes::get_Java_u2(p) : (u1)(*p);
308 constantTag tag = _pool->tag_at(cp_index).value();
309 if (tag.is_method_handle() || tag.is_method_type() || tag.is_string()) {
310 int ref_index = cp_entry_to_resolved_references(cp_index);
311 if (is_wide) {
504 }
505 }
506
507 // May have to fix invokedynamic bytecodes if invokestatic/InterfaceMethodref
508 // entries had to be added.
509 patch_invokedynamic_bytecodes();
510 }
511
512 void Rewriter::rewrite(instanceKlassHandle klass, TRAPS) {
513 if (!DumpSharedSpaces) {
514 assert(!MetaspaceShared::is_in_shared_space(klass()), "archive methods must not be rewritten at run time");
515 }
516 ResourceMark rm(THREAD);
517 Rewriter rw(klass, klass->constants(), klass->methods(), CHECK);
518 // (That's all, folks.)
519 }
520
521 Rewriter::Rewriter(instanceKlassHandle klass, const constantPoolHandle& cpool, Array<Method*>* methods, TRAPS)
522 : _klass(klass),
523 _pool(cpool),
524 _methods(methods),
525 _cp_map(cpool->length()),
526 _cp_cache_map(cpool->length() / 2),
527 _reference_map(cpool->length()),
528 _resolved_references_map(cpool->length() / 2),
529 _invokedynamic_references_map(cpool->length() / 2),
530 _method_handle_invokers(cpool->length()),
531 _invokedynamic_cp_cache_map(cpool->length() / 4)
532 {
533
534 // Rewrite bytecodes - exception here exits.
535 rewrite_bytecodes(CHECK);
536
537 // Stress restoring bytecodes
538 if (StressRewriter) {
539 restore_bytecodes();
540 rewrite_bytecodes(CHECK);
541 }
542
543 // allocate constant pool cache, now that we've seen all the bytecodes
544 make_constant_pool_cache(THREAD);
545
546 // Restore bytecodes to their unrewritten state if there are exceptions
547 // rewriting bytecodes or allocating the cpCache
548 if (HAS_PENDING_EXCEPTION) {
549 restore_bytecodes();
550 return;
551 }
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