1 /*
2 * Copyright (c) 2011, 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 */
23
24 package jdk.vm.ci.hotspot;
25
26 import static jdk.vm.ci.common.InitTimer.timer;
27 import static jdk.vm.ci.hotspot.HotSpotJVMCIRuntime.runtime;
28
29 import java.lang.reflect.Executable;
30
31 import jdk.vm.ci.code.BytecodeFrame;
32 import jdk.vm.ci.code.InstalledCode;
33 import jdk.vm.ci.code.InvalidInstalledCodeException;
34 import jdk.vm.ci.code.TargetDescription;
35 import jdk.vm.ci.code.stack.InspectedFrameVisitor;
36 import jdk.vm.ci.common.InitTimer;
37 import jdk.vm.ci.common.JVMCIError;
38 import jdk.vm.ci.meta.JavaType;
39 import jdk.vm.ci.meta.ResolvedJavaMethod;
40 import jdk.vm.ci.meta.ResolvedJavaType;
41
42 /**
43 * Calls from Java into HotSpot. The behavior of all the methods in this class that take a native
44 * pointer as an argument (e.g., {@link #getSymbol(long)}) is undefined if the argument does not
45 * denote a valid native object.
46 */
47 final class CompilerToVM {
48 /**
49 * Initializes the native part of the JVMCI runtime.
50 */
51 private static native void registerNatives();
52
53 static {
54 initialize();
55 }
56
57 @SuppressWarnings("try")
58 private static void initialize() {
59 try (InitTimer t = timer("CompilerToVM.registerNatives")) {
60 registerNatives();
61 }
62 }
63
64 /**
65 * Gets the {@link CompilerToVM} instance associated with the singleton
66 * {@link HotSpotJVMCIRuntime} instance.
67 */
68 public static CompilerToVM compilerToVM() {
69 return runtime().getCompilerToVM();
70 }
71
72 /**
73 * Copies the original bytecode of {@code method} into a new byte array and returns it.
74 *
75 * @return a new byte array containing the original bytecode of {@code method}
76 */
77 native byte[] getBytecode(HotSpotResolvedJavaMethodImpl method);
78
79 /**
80 * Gets the number of entries in {@code method}'s exception handler table or 0 if it has no
81 * exception handler table.
82 */
83 native int getExceptionTableLength(HotSpotResolvedJavaMethodImpl method);
84
85 /**
86 * Gets the address of the first entry in {@code method}'s exception handler table.
87 *
88 * Each entry is a native object described by these fields:
89 *
90 * <ul>
91 * <li>{@link HotSpotVMConfig#exceptionTableElementSize}</li>
92 * <li>{@link HotSpotVMConfig#exceptionTableElementStartPcOffset}</li>
93 * <li>{@link HotSpotVMConfig#exceptionTableElementEndPcOffset}</li>
94 * <li>{@link HotSpotVMConfig#exceptionTableElementHandlerPcOffset}</li>
95 * <li>{@link HotSpotVMConfig#exceptionTableElementCatchTypeIndexOffset}
96 * </ul>
97 *
98 * @return 0 if {@code method} has no exception handlers (i.e.
99 * {@code getExceptionTableLength(method) == 0})
100 */
101 native long getExceptionTableStart(HotSpotResolvedJavaMethodImpl method);
102
103 /**
104 * Determines whether {@code method} is currently compilable by the JVMCI compiler being used by
105 * the VM. This can return false if JVMCI compilation failed earlier for {@code method}, a
106 * breakpoint is currently set in {@code method} or {@code method} contains other bytecode
107 * features that require special handling by the VM.
108 */
109 native boolean isCompilable(HotSpotResolvedJavaMethodImpl method);
110
111 /**
112 * Determines if {@code method} is targeted by a VM directive (e.g.,
113 * {@code -XX:CompileCommand=dontinline,<pattern>}) or annotation (e.g.,
114 * {@code jdk.internal.vm.annotation.DontInline}) that specifies it should not be inlined.
115 */
116 native boolean hasNeverInlineDirective(HotSpotResolvedJavaMethodImpl method);
117
118 /**
119 * Determines if {@code method} should be inlined at any cost. This could be because:
120 * <ul>
121 * <li>a CompileOracle directive may forces inlining of this methods</li>
122 * <li>an annotation forces inlining of this method</li>
123 * </ul>
124 */
125 native boolean shouldInlineMethod(HotSpotResolvedJavaMethodImpl method);
126
127 /**
128 * Used to implement {@link ResolvedJavaType#findUniqueConcreteMethod(ResolvedJavaMethod)}.
129 *
130 * @param method the method on which to base the search
131 * @param actualHolderType the best known type of receiver
132 * @return the method result or 0 is there is no unique concrete method for {@code method}
133 */
134 native HotSpotResolvedJavaMethodImpl findUniqueConcreteMethod(HotSpotResolvedObjectTypeImpl actualHolderType, HotSpotResolvedJavaMethodImpl method);
135
136 /**
137 * Gets the implementor for the interface class {@code type}.
138 *
139 * @return the implementor if there is a single implementor, {@code null} if there is no
140 * implementor, or {@code type} itself if there is more than one implementor
141 * @throws IllegalArgumentException if type is not an interface type
142 */
143 native HotSpotResolvedObjectTypeImpl getImplementor(HotSpotResolvedObjectTypeImpl type);
144
145 /**
146 * Determines if {@code method} is ignored by security stack walks.
147 */
148 native boolean methodIsIgnoredBySecurityStackWalk(HotSpotResolvedJavaMethodImpl method);
149
150 /**
151 * Converts a name to a type.
152 *
153 * @param name a well formed Java type in {@linkplain JavaType#getName() internal} format
154 * @param accessingClass the context of resolution (must not be null)
155 * @param resolve force resolution to a {@link ResolvedJavaType}. If true, this method will
156 * either return a {@link ResolvedJavaType} or throw an exception
157 * @return the type for {@code name} or 0 if resolution failed and {@code resolve == false}
158 * @throws ClassNotFoundException if {@code resolve == true} and the resolution failed
159 */
160 native HotSpotResolvedObjectTypeImpl lookupType(String name, Class<?> accessingClass, boolean resolve) throws ClassNotFoundException;
161
162 /**
163 * Resolves the entry at index {@code cpi} in {@code constantPool} to an object.
164 *
165 * The behavior of this method is undefined if {@code cpi} does not denote one of the following
166 * entry types: {@code JVM_CONSTANT_MethodHandle}, {@code JVM_CONSTANT_MethodHandleInError},
167 * {@code JVM_CONSTANT_MethodType} and {@code JVM_CONSTANT_MethodTypeInError}.
168 */
169 native Object resolveConstantInPool(HotSpotConstantPool constantPool, int cpi);
170
171 /**
172 * Resolves the entry at index {@code cpi} in {@code constantPool} to an object, looking in the
173 * constant pool cache first.
174 *
175 * The behavior of this method is undefined if {@code cpi} does not denote a
176 * {@code JVM_CONSTANT_String} entry.
177 */
178 native Object resolvePossiblyCachedConstantInPool(HotSpotConstantPool constantPool, int cpi);
179
180 /**
181 * Gets the {@code JVM_CONSTANT_NameAndType} index from the entry at index {@code cpi} in
182 * {@code constantPool}.
183 *
184 * The behavior of this method is undefined if {@code cpi} does not denote an entry containing a
185 * {@code JVM_CONSTANT_NameAndType} index.
186 */
187 native int lookupNameAndTypeRefIndexInPool(HotSpotConstantPool constantPool, int cpi);
188
189 /**
190 * Gets the name of the {@code JVM_CONSTANT_NameAndType} entry referenced by another entry
191 * denoted by {@code which} in {@code constantPool}.
192 *
193 * The behavior of this method is undefined if {@code which} does not denote a entry that
194 * references a {@code JVM_CONSTANT_NameAndType} entry.
195 */
196 native String lookupNameInPool(HotSpotConstantPool constantPool, int which);
197
198 /**
199 * Gets the signature of the {@code JVM_CONSTANT_NameAndType} entry referenced by another entry
200 * denoted by {@code which} in {@code constantPool}.
201 *
202 * The behavior of this method is undefined if {@code which} does not denote a entry that
203 * references a {@code JVM_CONSTANT_NameAndType} entry.
204 */
205 native String lookupSignatureInPool(HotSpotConstantPool constantPool, int which);
206
207 /**
208 * Gets the {@code JVM_CONSTANT_Class} index from the entry at index {@code cpi} in
209 * {@code constantPool}.
210 *
211 * The behavior of this method is undefined if {@code cpi} does not denote an entry containing a
212 * {@code JVM_CONSTANT_Class} index.
213 */
214 native int lookupKlassRefIndexInPool(HotSpotConstantPool constantPool, int cpi);
215
216 /**
217 * Looks up a class denoted by the {@code JVM_CONSTANT_Class} entry at index {@code cpi} in
218 * {@code constantPool}. This method does not perform any resolution.
219 *
220 * The behavior of this method is undefined if {@code cpi} does not denote a
221 * {@code JVM_CONSTANT_Class} entry.
222 *
223 * @return the resolved class entry or a String otherwise
224 */
225 native Object lookupKlassInPool(HotSpotConstantPool constantPool, int cpi);
226
227 /**
228 * Looks up a method denoted by the entry at index {@code cpi} in {@code constantPool}. This
229 * method does not perform any resolution.
230 *
231 * The behavior of this method is undefined if {@code cpi} does not denote an entry representing
232 * a method.
233 *
234 * @param opcode the opcode of the instruction for which the lookup is being performed or
235 * {@code -1}. If non-negative, then resolution checks specific to the bytecode it
236 * denotes are performed if the method is already resolved. Should any of these
237 * checks fail, 0 is returned.
238 * @return the resolved method entry, 0 otherwise
239 */
240 native HotSpotResolvedJavaMethodImpl lookupMethodInPool(HotSpotConstantPool constantPool, int cpi, byte opcode);
241
242 // TODO resolving JVM_CONSTANT_Dynamic
243
244 /**
245 * Ensures that the type referenced by the specified {@code JVM_CONSTANT_InvokeDynamic} entry at
246 * index {@code cpi} in {@code constantPool} is loaded and initialized.
247 *
248 * The behavior of this method is undefined if {@code cpi} does not denote a
249 * {@code JVM_CONSTANT_InvokeDynamic} entry.
250 */
251 native void resolveInvokeDynamicInPool(HotSpotConstantPool constantPool, int cpi);
252
253 /**
254 * If {@code cpi} denotes an entry representing a
255 * <a href="https://docs.oracle.com/javase/specs/jvms/se8/html/jvms-2.html#jvms-2.9">signature
256 * polymorphic</a> method, this method ensures that the type referenced by the entry is loaded
257 * and initialized. It {@code cpi} does not denote a signature polymorphic method, this method
258 * does nothing.
259 */
260 native void resolveInvokeHandleInPool(HotSpotConstantPool constantPool, int cpi);
261
262 /**
263 * If {@code cpi} denotes an entry representing a resolved dynamic adapter (see
264 * {@link #resolveInvokeDynamicInPool} and {@link #resolveInvokeHandleInPool}), return the
265 * opcode of the instruction for which the resolution was performed ({@code invokedynamic} or
266 * {@code invokevirtual}), or {@code -1} otherwise.
267 */
268 native int isResolvedInvokeHandleInPool(HotSpotConstantPool constantPool, int cpi);
269
270 /**
271 * Gets the list of type names (in the format of {@link JavaType#getName()}) denoting the
272 * classes that define signature polymorphic methods.
273 */
274 native String[] getSignaturePolymorphicHolders();
275
276 /**
277 * Gets the resolved type denoted by the entry at index {@code cpi} in {@code constantPool}.
278 *
279 * The behavior of this method is undefined if {@code cpi} does not denote an entry representing
280 * a class.
281 *
282 * @throws LinkageError if resolution failed
283 */
284 native HotSpotResolvedObjectTypeImpl resolveTypeInPool(HotSpotConstantPool constantPool, int cpi) throws LinkageError;
285
286 /**
287 * Looks up and attempts to resolve the {@code JVM_CONSTANT_Field} entry for at index
288 * {@code cpi} in {@code constantPool}. For some opcodes, checks are performed that require the
289 * {@code method} that contains {@code opcode} to be specified. The values returned in
290 * {@code info} are:
291 *
292 * <pre>
293 * [ flags, // fieldDescriptor::access_flags()
294 * offset, // fieldDescriptor::offset()
295 * index // fieldDescriptor::index()
296 * ]
297 * </pre>
298 *
299 * The behavior of this method is undefined if {@code cpi} does not denote a
300 * {@code JVM_CONSTANT_Field} entry.
301 *
302 * @param info an array in which the details of the field are returned
303 * @return the type defining the field if resolution is successful, 0 otherwise
304 */
305 native HotSpotResolvedObjectTypeImpl resolveFieldInPool(HotSpotConstantPool constantPool, int cpi, HotSpotResolvedJavaMethodImpl method, byte opcode, int[] info);
306
307 /**
308 * Converts {@code cpci} from an index into the cache for {@code constantPool} to an index
309 * directly into {@code constantPool}.
310 *
311 * The behavior of this method is undefined if {@code ccpi} is an invalid constant pool cache
312 * index.
313 */
314 native int constantPoolRemapInstructionOperandFromCache(HotSpotConstantPool constantPool, int cpci);
315
316 /**
317 * Gets the appendix object (if any) associated with the entry at index {@code cpi} in
318 * {@code constantPool}.
319 */
320 native Object lookupAppendixInPool(HotSpotConstantPool constantPool, int cpi);
321
322 /**
323 * Installs the result of a compilation into the code cache.
324 *
325 * @param target the target where this code should be installed
326 * @param compiledCode the result of a compilation
327 * @param code the details of the installed CodeBlob are written to this object
328 * @return the outcome of the installation which will be one of
329 * {@link HotSpotVMConfig#codeInstallResultOk},
330 * {@link HotSpotVMConfig#codeInstallResultCacheFull},
331 * {@link HotSpotVMConfig#codeInstallResultCodeTooLarge},
332 * {@link HotSpotVMConfig#codeInstallResultDependenciesFailed} or
333 * {@link HotSpotVMConfig#codeInstallResultDependenciesInvalid}.
334 * @throws JVMCIError if there is something wrong with the compiled code or the associated
335 * metadata.
336 */
337 native int installCode(TargetDescription target, HotSpotCompiledCode compiledCode, InstalledCode code, HotSpotSpeculationLog speculationLog);
338
339 /**
340 * Generates the VM metadata for some compiled code and copies them into {@code metaData}. This
341 * method does not install anything into the code cache.
342 *
343 * @param target the target where this code would be installed
344 * @param compiledCode the result of a compilation
345 * @param metaData the metadata is written to this object
346 * @return the outcome of the installation which will be one of
347 * {@link HotSpotVMConfig#codeInstallResultOk},
348 * {@link HotSpotVMConfig#codeInstallResultCacheFull},
349 * {@link HotSpotVMConfig#codeInstallResultCodeTooLarge},
350 * {@link HotSpotVMConfig#codeInstallResultDependenciesFailed} or
351 * {@link HotSpotVMConfig#codeInstallResultDependenciesInvalid}.
352 * @throws JVMCIError if there is something wrong with the compiled code or the metadata
353 */
354 native int getMetadata(TargetDescription target, HotSpotCompiledCode compiledCode, HotSpotMetaData metaData);
355
356 /**
357 * Resets all compilation statistics.
358 */
359 native void resetCompilationStatistics();
360
361 /**
362 * Reads the database of VM info. The return value encodes the info in a nested object array
363 * that is described by the pseudo Java object {@code info} below:
364 *
365 * <pre>
366 * info = [
367 * VMField[] vmFields,
368 * [String name, Long size, ...] vmTypeSizes,
369 * [String name, Long value, ...] vmConstants,
370 * [String name, Long value, ...] vmAddresses,
371 * VMFlag[] vmFlags
372 * VMIntrinsicMethod[] vmIntrinsics
373 * ]
374 * </pre>
375 *
376 * @return VM info as encoded above
377 */
378 native Object[] readConfiguration();
379
380 /**
381 * Resolves the implementation of {@code method} for virtual dispatches on objects of dynamic
382 * type {@code exactReceiver}. This resolution process only searches "up" the class hierarchy of
383 * {@code exactReceiver}.
384 *
385 * @param caller the caller or context type used to perform access checks
386 * @return the link-time resolved method (might be abstract) or {@code null} if it is either a
387 * signature polymorphic method or can not be linked.
388 */
389 native HotSpotResolvedJavaMethodImpl resolveMethod(HotSpotResolvedObjectTypeImpl exactReceiver, HotSpotResolvedJavaMethodImpl method, HotSpotResolvedObjectTypeImpl caller);
390
391 /**
392 * Gets the static initializer of {@code type}.
393 *
394 * @return {@code null} if {@code type} has no static initializer
395 */
396 native HotSpotResolvedJavaMethodImpl getClassInitializer(HotSpotResolvedObjectTypeImpl type);
397
398 /**
399 * Determines if {@code type} or any of its currently loaded subclasses overrides
400 * {@code Object.finalize()}.
401 */
402 native boolean hasFinalizableSubclass(HotSpotResolvedObjectTypeImpl type);
403
404 /**
405 * Gets the method corresponding to {@code executable}.
406 */
407 native HotSpotResolvedJavaMethodImpl asResolvedJavaMethod(Executable executable);
408
409 /**
410 * Gets the maximum absolute offset of a PC relative call to {@code address} from any position
411 * in the code cache.
412 *
413 * @param address an address that may be called from any code in the code cache
414 * @return -1 if {@code address == 0}
415 */
416 native long getMaxCallTargetOffset(long address);
417
418 /**
419 * Gets a textual disassembly of {@code codeBlob}.
420 *
421 * @return a non-zero length string containing a disassembly of {@code codeBlob} or null if
422 * {@code codeBlob} could not be disassembled for some reason
423 */
424 // The HotSpot disassembler seems not to be thread safe so it's better to synchronize its usage
425 synchronized native String disassembleCodeBlob(InstalledCode installedCode);
426
427 /**
428 * Gets a stack trace element for {@code method} at bytecode index {@code bci}.
429 */
430 native StackTraceElement getStackTraceElement(HotSpotResolvedJavaMethodImpl method, int bci);
431
432 /**
433 * Executes some {@code installedCode} with arguments {@code args}.
434 *
435 * @return the result of executing {@code installedCode}
436 * @throws InvalidInstalledCodeException if {@code installedCode} has been invalidated
437 */
438 native Object executeInstalledCode(Object[] args, InstalledCode installedCode) throws InvalidInstalledCodeException;
439
440 /**
441 * Gets the line number table for {@code method}. The line number table is encoded as (bci,
442 * source line number) pairs.
443 *
444 * @return the line number table for {@code method} or null if it doesn't have one
445 */
446 native long[] getLineNumberTable(HotSpotResolvedJavaMethodImpl method);
447
448 /**
449 * Gets the number of entries in the local variable table for {@code method}.
450 *
451 * @return the number of entries in the local variable table for {@code method}
452 */
453 native int getLocalVariableTableLength(HotSpotResolvedJavaMethodImpl method);
454
455 /**
456 * Gets the address of the first entry in the local variable table for {@code method}.
457 *
458 * Each entry is a native object described by these fields:
459 *
460 * <ul>
461 * <li>{@link HotSpotVMConfig#localVariableTableElementSize}</li>
462 * <li>{@link HotSpotVMConfig#localVariableTableElementLengthOffset}</li>
463 * <li>{@link HotSpotVMConfig#localVariableTableElementNameCpIndexOffset}</li>
464 * <li>{@link HotSpotVMConfig#localVariableTableElementDescriptorCpIndexOffset}</li>
465 * <li>{@link HotSpotVMConfig#localVariableTableElementSlotOffset}
466 * <li>{@link HotSpotVMConfig#localVariableTableElementStartBciOffset}
467 * </ul>
468 *
469 * @return 0 if {@code method} does not have a local variable table
470 */
471 native long getLocalVariableTableStart(HotSpotResolvedJavaMethodImpl method);
472
473 /**
474 * Sets flags on {@code method} indicating that it should never be inlined or compiled by the
475 * VM.
476 */
477 native void setNotInlinableOrCompilable(HotSpotResolvedJavaMethodImpl method);
478
479 /**
480 * Invalidates the profiling information for {@code method} and (re)initializes it such that
481 * profiling restarts upon its next invocation.
482 */
483 native void reprofile(HotSpotResolvedJavaMethodImpl method);
484
485 /**
486 * Invalidates {@code installedCode} such that {@link InvalidInstalledCodeException} will be
487 * raised the next time {@code installedCode} is executed.
488 */
489 native void invalidateInstalledCode(InstalledCode installedCode);
490
491 /**
492 * Collects the current values of all JVMCI benchmark counters, summed up over all threads.
493 */
494 native long[] collectCounters();
495
496 /**
497 * Determines if {@code metaspaceMethodData} is mature.
498 */
499 native boolean isMature(long metaspaceMethodData);
500
501 /**
502 * Generate a unique id to identify the result of the compile.
503 */
504 native int allocateCompileId(HotSpotResolvedJavaMethodImpl method, int entryBCI);
505
506 /**
507 * Determines if {@code method} has OSR compiled code identified by {@code entryBCI} for
508 * compilation level {@code level}.
509 */
510 native boolean hasCompiledCodeForOSR(HotSpotResolvedJavaMethodImpl method, int entryBCI, int level);
511
512 /**
513 * Gets the value of {@code metaspaceSymbol} as a String.
514 */
515 native String getSymbol(long metaspaceSymbol);
516
517 /**
518 * @see jdk.vm.ci.code.stack.StackIntrospection#iterateFrames
519 */
520 native <T> T iterateFrames(ResolvedJavaMethod[] initialMethods, ResolvedJavaMethod[] matchingMethods, int initialSkip, InspectedFrameVisitor<T> visitor);
521
522 /**
523 * Materializes all virtual objects within {@code stackFrame} and updates its locals.
524 *
525 * @param invalidate if {@code true}, the compiled method for the stack frame will be
526 * invalidated
527 */
528 native void materializeVirtualObjects(HotSpotStackFrameReference stackFrame, boolean invalidate);
529
530 /**
531 * Gets the v-table index for interface method {@code method} in the receiver {@code type} or
532 * {@link HotSpotVMConfig#invalidVtableIndex} if {@code method} is not in {@code type}'s
533 * v-table.
534 *
535 * @throws InternalError if {@code type} is an interface or {@code method} is not held by an
536 * interface or class represented by {@code type} is not initialized
537 */
538 native int getVtableIndexForInterfaceMethod(HotSpotResolvedObjectTypeImpl type, HotSpotResolvedJavaMethodImpl method);
539
540 /**
541 * Determines if debug info should also be emitted at non-safepoint locations.
542 */
543 native boolean shouldDebugNonSafepoints();
544
545 /**
546 * Writes {@code length} bytes from {@code bytes} starting at offset {@code offset} to HotSpot's
547 * log stream.
548 *
549 * @throws NullPointerException if {@code bytes == null}
550 * @throws IndexOutOfBoundsException if copying would cause access of data outside array bounds
551 */
552 native void writeDebugOutput(byte[] bytes, int offset, int length);
553
554 /**
555 * Flush HotSpot's log stream.
556 */
557 native void flushDebugOutput();
558
559 /**
560 * Read a HotSpot Method* value from the memory location described by {@code base} plus
561 * {@code displacement} and return the {@link HotSpotResolvedJavaMethodImpl} wrapping it. This
562 * method does no checking that the memory location actually contains a valid pointer and may
563 * crash the VM if an invalid location is provided. If the {@code base} is null then
564 * {@code displacement} is used by itself. If {@code base} is a
565 * {@link HotSpotResolvedJavaMethodImpl}, {@link HotSpotConstantPool} or
566 * {@link HotSpotResolvedObjectTypeImpl} then the metaspace pointer is fetched from that object
567 * and added to {@code displacement}. Any other non-null object type causes an
568 * {@link IllegalArgumentException} to be thrown.
569 *
570 * @param base an object to read from or null
571 * @param displacement
572 * @return null or the resolved method for this location
573 */
574 native HotSpotResolvedJavaMethodImpl getResolvedJavaMethod(Object base, long displacement);
575
576 /**
577 * Gets the {@code ConstantPool*} associated with {@code object} and returns a
578 * {@link HotSpotConstantPool} wrapping it.
579 *
580 * @param object a {@link HotSpotResolvedJavaMethodImpl} or
581 * {@link HotSpotResolvedObjectTypeImpl} object
582 * @return a {@link HotSpotConstantPool} wrapping the {@code ConstantPool*} associated with
583 * {@code object}
584 * @throws NullPointerException if {@code object == null}
585 * @throws IllegalArgumentException if {@code object} is neither a
586 * {@link HotSpotResolvedJavaMethodImpl} nor a {@link HotSpotResolvedObjectTypeImpl}
587 */
588 native HotSpotConstantPool getConstantPool(Object object);
589
590 /**
591 * Read a HotSpot Klass* value from the memory location described by {@code base} plus
592 * {@code displacement} and return the {@link HotSpotResolvedObjectTypeImpl} wrapping it. This
593 * method does no checking that the memory location actually contains a valid pointer and may
594 * crash the VM if an invalid location is provided. If the {@code base} is null then
595 * {@code displacement} is used by itself. If {@code base} is a
596 * {@link HotSpotResolvedJavaMethodImpl}, {@link HotSpotConstantPool} or
597 * {@link HotSpotResolvedObjectTypeImpl} then the metaspace pointer is fetched from that object
598 * and added to {@code displacement}. Any other non-null object type causes an
599 * {@link IllegalArgumentException} to be thrown.
600 *
601 * @param base an object to read from or null
602 * @param displacement
603 * @param compressed true if the location contains a compressed Klass*
604 * @return null or the resolved method for this location
605 */
606 native HotSpotResolvedObjectTypeImpl getResolvedJavaType(Object base, long displacement, boolean compressed);
607
608 /**
609 * Return the size of the HotSpot ProfileData* pointed at by {@code position}. If
610 * {@code position} is outside the space of the MethodData then an
611 * {@link IllegalArgumentException} is thrown. A {@code position} inside the MethodData but that
612 * isn't pointing at a valid ProfileData will crash the VM.
613 *
614 * @param metaspaceMethodData
615 * @param position
616 * @return the size of the ProfileData item pointed at by {@code position}
617 * @throws IllegalArgumentException if an out of range position is given
618 */
619 native int methodDataProfileDataSize(long metaspaceMethodData, int position);
620
621 /**
622 * Gets the fingerprint for a given Klass*.
623 *
624 * @param metaspaceKlass
625 * @return the value of the fingerprint (zero for arrays and synthetic classes).
626 */
627 native long getFingerprint(long metaspaceKlass);
628
629 /**
630 * Return the amount of native stack required for the interpreter frames represented by
631 * {@code frame}. This is used when emitting the stack banging code to ensure that there is
632 * enough space for the frames during deoptimization.
633 *
634 * @param frame
635 * @return the number of bytes required for deoptimization of this frame state
636 */
637 native int interpreterFrameSize(BytecodeFrame frame);
638
639 /**
640 * Invokes non-public method {@code java.lang.invoke.LambdaForm.compileToBytecode()} on
641 * {@code lambdaForm} (which must be a {@code java.lang.invoke.LambdaForm} instance).
642 */
643 native void compileToBytecode(Object lambdaForm);
644
645 /**
646 * Gets the value of the VM flag named {@code name}.
647 *
648 * @param name name of a VM option
649 * @return {@code this} if the named VM option doesn't exist, a {@link String} or {@code null}
650 * if its type is {@code ccstr} or {@code ccstrlist}, a {@link Double} if its type is
651 * {@code double}, a {@link Boolean} if its type is {@code bool} otherwise a
652 * {@link Long}
653 */
654 native Object getFlagValue(String name);
655
656 /**
657 * Gets the host class for {@code type}.
658 */
659 native HotSpotResolvedObjectTypeImpl getHostClass(HotSpotResolvedObjectTypeImpl type);
660 }