1 /*
  2  * Copyright (c) 2009, 2022, 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 package jdk.vm.ci.meta;
 24 
 25 import java.lang.annotation.Annotation;
 26 import java.lang.reflect.AnnotatedElement;
 27 import java.lang.reflect.Array;
 28 import java.lang.reflect.Method;
 29 import java.lang.reflect.Modifier;
 30 import java.lang.reflect.Type;
 31 
 32 /**
 33  * Represents a resolved Java method. Methods, like fields and types, are resolved through
 34  * {@link ConstantPool constant pools}.
 35  */
 36 public interface ResolvedJavaMethod extends JavaMethod, InvokeTarget, ModifiersProvider, AnnotatedElement {
 37 
 38     /**
 39      * Returns the method's bytecode. The returned bytecode does not contain breakpoints or non-Java
 40      * bytecodes. This will return {@code null} if {@link #getCodeSize()} returns {@code <= 0} or if
 41      * {@link #hasBytecodes()} returns {@code false}.
 42      *
 43      * The contained constant pool indexes may not be the ones found in the original class file but
 44      * they can be used with the JVMCI API (e.g. methods in {@link ConstantPool}).
 45      *
 46      * @return {@code null} if {@code getLinkedCodeSize() <= 0} otherwise the bytecode of the method
 47      *         whose length is guaranteed to be {@code > 0}
 48      */
 49     byte[] getCode();
 50 
 51     /**
 52      * Returns the size of the method's bytecode. If this method returns a value {@code > 0} then
 53      * {@link #getCode()} will not return {@code null}.
 54      *
 55      * @return 0 if the method has no bytecode, {@code -1} if the method does have bytecode but its
 56      *         {@linkplain #getDeclaringClass() declaring class} is not
 57      *         {@linkplain ResolvedJavaType#isLinked() linked} otherwise the size of the bytecode in
 58      *         bytes (guaranteed to be {@code > 0})
 59      */
 60     int getCodeSize();
 61 
 62     /**
 63      * Returns the {@link ResolvedJavaType} object representing the class or interface that declares
 64      * this method.
 65      */
 66     @Override
 67     ResolvedJavaType getDeclaringClass();
 68 
 69     /**
 70      * Returns the maximum number of locals used in this method's bytecodes.
 71      */
 72     int getMaxLocals();
 73 
 74     /**
 75      * Returns the maximum number of stack slots used in this method's bytecodes.
 76      */
 77     int getMaxStackSize();
 78 
 79     default boolean isFinal() {
 80         return ModifiersProvider.super.isFinalFlagSet();
 81     }
 82 
 83     /**
 84      * Determines if this method is a synthetic method as defined by the Java Language
 85      * Specification.
 86      */
 87     boolean isSynthetic();
 88 
 89     /**
 90      * Checks if the method is a varargs method.
 91      *
 92      * @return whether the method is a varargs method
 93      * @jvms 4.6
 94      */
 95     boolean isVarArgs();
 96 
 97     /**
 98      * Checks if the method is a bridge method.
 99      *
100      * @return whether the method is a bridge method
101      * @jvms 4.6
102      */
103     boolean isBridge();
104 
105     /**
106      * Returns {@code true} if this method is a default method; returns {@code false} otherwise.
107      *
108      * A default method is a public non-abstract instance method, that is, a non-static method with
109      * a body, declared in an interface type.
110      *
111      * @return true if and only if this method is a default method as defined by the Java Language
112      *         Specification.
113      */
114     boolean isDefault();
115 
116     /**
117      * Checks whether this method is a class initializer.
118      *
119      * @return {@code true} if the method is a class initializer
120      */
121     boolean isClassInitializer();
122 
123     /**
124      * Checks whether this method is a constructor.
125      *
126      * @return {@code true} if the method is a constructor
127      */
128     boolean isConstructor();
129 
130     /**
131      * Checks whether this method can be statically bound (usually, that means it is final or
132      * private or static, but not abstract, or the declaring class is final).
133      *
134      * @return {@code true} if this method can be statically bound
135      */
136     boolean canBeStaticallyBound();
137 
138     /**
139      * Returns the list of exception handlers for this method.
140      */
141     ExceptionHandler[] getExceptionHandlers();
142 
143     /**
144      * Returns a stack trace element for this method and a given bytecode index.
145      */
146     StackTraceElement asStackTraceElement(int bci);
147 
148     /**
149      * Returns an object that provides access to the profiling information recorded for this method.
150      */
151     default ProfilingInfo getProfilingInfo() {
152         return getProfilingInfo(true, true);
153     }
154 
155     /**
156      * Returns an object that provides access to the profiling information recorded for this method.
157      *
158      * @param includeNormal if true,
159      *            {@linkplain ProfilingInfo#getDeoptimizationCount(DeoptimizationReason)
160      *            deoptimization counts} will include deoptimization that happened during execution
161      *            of standard non-osr methods.
162      * @param includeOSR if true,
163      *            {@linkplain ProfilingInfo#getDeoptimizationCount(DeoptimizationReason)
164      *            deoptimization counts} will include deoptimization that happened during execution
165      *            of on-stack-replacement methods.
166      */
167     ProfilingInfo getProfilingInfo(boolean includeNormal, boolean includeOSR);
168 
169     /**
170      * Invalidates the profiling information and restarts profiling upon the next invocation.
171      */
172     void reprofile();
173 
174     /**
175      * Returns the constant pool of this method.
176      */
177     ConstantPool getConstantPool();
178 
179     /**
180      * A {@code Parameter} provides information about method parameters.
181      */
182     class Parameter implements AnnotatedElement {
183         private final String name;
184         private final ResolvedJavaMethod method;
185         private final int modifiers;
186         private final int index;
187 
188         /**
189          * Constructor for {@code Parameter}.
190          *
191          * @param name the name of the parameter or {@code null} if there is no
192          *            {@literal MethodParameters} class file attribute providing a non-empty name
193          *            for the parameter
194          * @param modifiers the modifier flags for the parameter
195          * @param method the method which defines this parameter
196          * @param index the index of the parameter
197          */
198         public Parameter(String name,
199                         int modifiers,
200                         ResolvedJavaMethod method,
201                         int index) {
202             assert name == null || !name.isEmpty();
203             this.name = name;
204             this.modifiers = modifiers;
205             this.method = method;
206             this.index = index;
207         }
208 
209         /**
210          * Gets the name of the parameter. If the parameter's name is {@linkplain #isNamePresent()
211          * present}, then this method returns the name provided by the class file. Otherwise, this
212          * method synthesizes a name of the form argN, where N is the index of the parameter in the
213          * descriptor of the method which declares the parameter.
214          *
215          * @return the name of the parameter, either provided by the class file or synthesized if
216          *         the class file does not provide a name
217          */
218         public String getName() {
219             if (name == null) {
220                 return "arg" + index;
221             } else {
222                 return name;
223             }
224         }
225 
226         /**
227          * Gets the method declaring the parameter.
228          */
229         public ResolvedJavaMethod getDeclaringMethod() {
230             return method;
231         }
232 
233         /**
234          * Get the modifier flags for the parameter.
235          */
236         public int getModifiers() {
237             return modifiers;
238         }
239 
240         /**
241          * Gets the kind of the parameter.
242          */
243         public JavaKind getKind() {
244             return method.getSignature().getParameterKind(index);
245         }
246 
247         /**
248          * Gets the formal type of the parameter.
249          */
250         public Type getParameterizedType() {
251             return method.getGenericParameterTypes()[index];
252         }
253 
254         /**
255          * Gets the type of the parameter.
256          */
257         public JavaType getType() {
258             return method.getSignature().getParameterType(index, method.getDeclaringClass());
259         }
260 
261         /**
262          * Determines if the parameter has a name according to a {@literal MethodParameters} class
263          * file attribute.
264          *
265          * @return true if and only if the parameter has a name according to the class file.
266          */
267         public boolean isNamePresent() {
268             return name != null;
269         }
270 
271         /**
272          * Determines if the parameter represents a variable argument list.
273          */
274         public boolean isVarArgs() {
275             return method.isVarArgs() && index == method.getSignature().getParameterCount(false) - 1;
276         }
277 
278         @Override
279         public <T extends Annotation> T getAnnotation(Class<T> annotationClass) {
280             return method.getParameterAnnotations(annotationClass)[index];
281         }
282 
283         @Override
284         public Annotation[] getAnnotations() {
285             return method.getParameterAnnotations()[index];
286         }
287 
288         @Override
289         public Annotation[] getDeclaredAnnotations() {
290             return getAnnotations();
291         }
292 
293         @Override
294         public String toString() {
295             Type type = getParameterizedType();
296             String typename = type.getTypeName();
297             if (isVarArgs()) {
298                 typename = typename.replaceFirst("\\[\\]$", "...");
299             }
300 
301             final StringBuilder sb = new StringBuilder(Modifier.toString(getModifiers()));
302             if (sb.length() != 0) {
303                 sb.append(' ');
304             }
305             return sb.append(typename).append(' ').append(getName()).toString();
306         }
307 
308         @Override
309         public boolean equals(Object obj) {
310             if (obj instanceof Parameter) {
311                 Parameter other = (Parameter) obj;
312                 return (other.method.equals(method) && other.index == index);
313             }
314             return false;
315         }
316 
317         @Override
318         public int hashCode() {
319             return method.hashCode() ^ index;
320         }
321     }
322 
323     /**
324      * Returns an array of {@code Parameter} objects that represent all the parameters to this
325      * method. Returns an array of length 0 if this method has no parameters. Returns {@code null}
326      * if the parameter information is unavailable.
327      */
328     default Parameter[] getParameters() {
329         return null;
330     }
331 
332     /**
333      * Returns an array of arrays that represent the annotations on the formal parameters, in
334      * declaration order, of this method.
335      *
336      * @see Method#getParameterAnnotations()
337      */
338     Annotation[][] getParameterAnnotations();
339 
340     /**
341      * Returns an array of {@link Type} objects that represent the formal parameter types, in
342      * declaration order, of this method.
343      *
344      * @see Method#getGenericParameterTypes()
345      */
346     Type[] getGenericParameterTypes();
347 
348     /**
349      * Returns {@code true} if this method is not excluded from inlining and has associated Java
350      * bytecodes (@see {@link ResolvedJavaMethod#hasBytecodes()}).
351      */
352     boolean canBeInlined();
353 
354     /**
355      * Determines if this method is targeted by a VM directive (e.g.,
356      * {@code -XX:CompileCommand=dontinline,<pattern>}) or VM recognized annotation (e.g.,
357      * {@code jdk.internal.vm.annotation.DontInline}) that specifies it should not be inlined.
358      */
359     boolean hasNeverInlineDirective();
360 
361     /**
362      * Returns {@code true} if the inlining of this method should be forced.
363      */
364     boolean shouldBeInlined();
365 
366     /**
367      * Returns the LineNumberTable of this method or null if this method does not have a line
368      * numbers table.
369      */
370     LineNumberTable getLineNumberTable();
371 
372     /**
373      * Returns the local variable table of this method or null if this method does not have a local
374      * variable table.
375      */
376     LocalVariableTable getLocalVariableTable();
377 
378     /**
379      * Gets the encoding of (that is, a constant representing the value of) this method.
380      *
381      * @return a constant representing a reference to this method
382      */
383     Constant getEncoding();
384 
385     /**
386      * Checks if this method is present in the virtual table for subtypes of the specified
387      * {@linkplain ResolvedJavaType type}.
388      *
389      * @return true is this method is present in the virtual table for subtypes of this type.
390      */
391     boolean isInVirtualMethodTable(ResolvedJavaType resolved);
392 
393     /**
394      * Gets the annotation of a particular type for a formal parameter of this method.
395      *
396      * @param annotationClass the Class object corresponding to the annotation type
397      * @param parameterIndex the index of a formal parameter of {@code method}
398      * @return the annotation of type {@code annotationClass} for the formal parameter present, else
399      *         null
400      * @throws IndexOutOfBoundsException if {@code parameterIndex} does not denote a formal
401      *             parameter
402      */
403     default <T extends Annotation> T getParameterAnnotation(Class<T> annotationClass, int parameterIndex) {
404         if (parameterIndex >= 0) {
405             Annotation[][] parameterAnnotations = getParameterAnnotations();
406             for (Annotation a : parameterAnnotations[parameterIndex]) {
407                 if (a.annotationType() == annotationClass) {
408                     return annotationClass.cast(a);
409                 }
410             }
411         }
412         return null;
413     }
414 
415     default JavaType[] toParameterTypes() {
416         JavaType receiver = isStatic() || isConstructor() ? null : getDeclaringClass();
417         return getSignature().toParameterTypes(receiver);
418     }
419 
420     /**
421      * Gets the annotations of a particular type for the formal parameters of this method.
422      *
423      * @param annotationClass the Class object corresponding to the annotation type
424      * @return the annotation of type {@code annotationClass} (if any) for each formal parameter
425      *         present
426      */
427     @SuppressWarnings("unchecked")
428     default <T extends Annotation> T[] getParameterAnnotations(Class<T> annotationClass) {
429         Annotation[][] parameterAnnotations = getParameterAnnotations();
430         T[] result = (T[]) Array.newInstance(annotationClass, parameterAnnotations.length);
431         for (int i = 0; i < parameterAnnotations.length; i++) {
432             for (Annotation a : parameterAnnotations[i]) {
433                 if (a.annotationType() == annotationClass) {
434                     result[i] = annotationClass.cast(a);
435                 }
436             }
437         }
438         return result;
439     }
440 
441     /**
442      * @see #getCodeSize()
443      * @return {@code getCodeSize() > 0}
444      */
445     default boolean hasBytecodes() {
446         return getCodeSize() > 0;
447     }
448 
449     /**
450      * Checks whether the method has a receiver parameter - i.e., whether it is not static.
451      *
452      * @return whether the method has a receiver parameter
453      */
454     default boolean hasReceiver() {
455         return !isStatic();
456     }
457 
458     /**
459      * Determines if this method is {@link java.lang.Object#Object()}.
460      */
461     default boolean isJavaLangObjectInit() {
462         return getDeclaringClass().isJavaLangObject() && getName().equals("<init>");
463     }
464 
465     /**
466      * Gets a speculation log that can be used when compiling this method to make new speculations
467      * and query previously failed speculations. The implementation may return a new
468      * {@link SpeculationLog} object each time this method is called so its the caller's
469      * responsibility to ensure the same speculation log is used throughout a compilation.
470      */
471     SpeculationLog getSpeculationLog();
472 }
--- EOF ---