1 /*
2 * Copyright (c) 2011, 2013, 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.lang.invoke;
27
28 import java.lang.annotation.*;
29 import java.lang.reflect.Method;
30 import java.util.Map;
31 import java.util.List;
32 import java.util.Arrays;
33 import java.util.ArrayList;
34 import java.util.HashMap;
35 import java.util.concurrent.ConcurrentHashMap;
36 import sun.invoke.util.Wrapper;
37 import static java.lang.invoke.MethodHandleStatics.*;
38 import static java.lang.invoke.MethodHandleNatives.Constants.*;
39 import java.lang.reflect.Field;
40 import java.util.Objects;
41
42 /**
43 * The symbolic, non-executable form of a method handle's invocation semantics.
44 * It consists of a series of names.
45 * The first N (N=arity) names are parameters,
46 * while any remaining names are temporary values.
47 * Each temporary specifies the application of a function to some arguments.
48 * The functions are method handles, while the arguments are mixes of
49 * constant values and local names.
50 * The result of the lambda is defined as one of the names, often the last one.
51 * <p>
52 * Here is an approximate grammar:
53 * <blockquote><pre>{@code
54 * LambdaForm = "(" ArgName* ")=>{" TempName* Result "}"
55 * ArgName = "a" N ":" T
56 * TempName = "t" N ":" T "=" Function "(" Argument* ");"
57 * Function = ConstantValue
58 * Argument = NameRef | ConstantValue
59 * Result = NameRef | "void"
60 * NameRef = "a" N | "t" N
61 * N = (any whole number)
62 * T = "L" | "I" | "J" | "F" | "D" | "V"
63 * }</pre></blockquote>
64 * Names are numbered consecutively from left to right starting at zero.
65 * (The letters are merely a taste of syntax sugar.)
66 * Thus, the first temporary (if any) is always numbered N (where N=arity).
67 * Every occurrence of a name reference in an argument list must refer to
68 * a name previously defined within the same lambda.
69 * A lambda has a void result if and only if its result index is -1.
70 * If a temporary has the type "V", it cannot be the subject of a NameRef,
71 * even though possesses a number.
72 * Note that all reference types are erased to "L", which stands for {@code Object}.
73 * All subword types (boolean, byte, short, char) are erased to "I" which is {@code int}.
74 * The other types stand for the usual primitive types.
75 * <p>
76 * Function invocation closely follows the static rules of the Java verifier.
77 * Arguments and return values must exactly match when their "Name" types are
78 * considered.
79 * Conversions are allowed only if they do not change the erased type.
80 * <ul>
81 * <li>L = Object: casts are used freely to convert into and out of reference types
82 * <li>I = int: subword types are forcibly narrowed when passed as arguments (see {@code explicitCastArguments})
83 * <li>J = long: no implicit conversions
84 * <li>F = float: no implicit conversions
85 * <li>D = double: no implicit conversions
86 * <li>V = void: a function result may be void if and only if its Name is of type "V"
87 * </ul>
88 * Although implicit conversions are not allowed, explicit ones can easily be
89 * encoded by using temporary expressions which call type-transformed identity functions.
90 * <p>
91 * Examples:
92 * <blockquote><pre>{@code
93 * (a0:J)=>{ a0 }
94 * == identity(long)
95 * (a0:I)=>{ t1:V = System.out#println(a0); void }
96 * == System.out#println(int)
97 * (a0:L)=>{ t1:V = System.out#println(a0); a0 }
98 * == identity, with printing side-effect
99 * (a0:L, a1:L)=>{ t2:L = BoundMethodHandle#argument(a0);
100 * t3:L = BoundMethodHandle#target(a0);
101 * t4:L = MethodHandle#invoke(t3, t2, a1); t4 }
102 * == general invoker for unary insertArgument combination
103 * (a0:L, a1:L)=>{ t2:L = FilterMethodHandle#filter(a0);
104 * t3:L = MethodHandle#invoke(t2, a1);
105 * t4:L = FilterMethodHandle#target(a0);
106 * t5:L = MethodHandle#invoke(t4, t3); t5 }
107 * == general invoker for unary filterArgument combination
108 * (a0:L, a1:L)=>{ ...(same as previous example)...
109 * t5:L = MethodHandle#invoke(t4, t3, a1); t5 }
110 * == general invoker for unary/unary foldArgument combination
111 * (a0:L, a1:I)=>{ t2:I = identity(long).asType((int)->long)(a1); t2 }
112 * == invoker for identity method handle which performs i2l
113 * (a0:L, a1:L)=>{ t2:L = BoundMethodHandle#argument(a0);
114 * t3:L = Class#cast(t2,a1); t3 }
115 * == invoker for identity method handle which performs cast
116 * }</pre></blockquote>
117 * <p>
118 * @author John Rose, JSR 292 EG
119 */
120 class LambdaForm {
121 final int arity;
122 final int result;
123 @Stable final Name[] names;
124 final String debugName;
125 MemberName vmentry; // low-level behavior, or null if not yet prepared
126 private boolean isCompiled;
127
128 // Caches for common structural transforms:
129 LambdaForm[] bindCache;
130
131 public static final int VOID_RESULT = -1, LAST_RESULT = -2;
132
133 LambdaForm(String debugName,
134 int arity, Name[] names, int result) {
135 assert(namesOK(arity, names));
136 this.arity = arity;
137 this.result = fixResult(result, names);
138 this.names = names.clone();
139 this.debugName = debugName;
140 normalize();
141 }
142
143 LambdaForm(String debugName,
144 int arity, Name[] names) {
145 this(debugName,
146 arity, names, LAST_RESULT);
147 }
148
149 LambdaForm(String debugName,
150 Name[] formals, Name[] temps, Name result) {
151 this(debugName,
152 formals.length, buildNames(formals, temps, result), LAST_RESULT);
153 }
154
155 private static Name[] buildNames(Name[] formals, Name[] temps, Name result) {
156 int arity = formals.length;
157 int length = arity + temps.length + (result == null ? 0 : 1);
158 Name[] names = Arrays.copyOf(formals, length);
159 System.arraycopy(temps, 0, names, arity, temps.length);
160 if (result != null)
161 names[length - 1] = result;
162 return names;
163 }
164
165 private LambdaForm(String sig) {
166 // Make a blank lambda form, which returns a constant zero or null.
167 // It is used as a template for managing the invocation of similar forms that are non-empty.
168 // Called only from getPreparedForm.
169 assert(isValidSignature(sig));
170 this.arity = signatureArity(sig);
171 this.result = (signatureReturn(sig) == 'V' ? -1 : arity);
172 this.names = buildEmptyNames(arity, sig);
173 this.debugName = "LF.zero";
174 assert(nameRefsAreLegal());
175 assert(isEmpty());
176 assert(sig.equals(basicTypeSignature()));
177 }
178
179 private static Name[] buildEmptyNames(int arity, String basicTypeSignature) {
180 assert(isValidSignature(basicTypeSignature));
181 int resultPos = arity + 1; // skip '_'
182 if (arity < 0 || basicTypeSignature.length() != resultPos+1)
183 throw new IllegalArgumentException("bad arity for "+basicTypeSignature);
184 int numRes = (basicTypeSignature.charAt(resultPos) == 'V' ? 0 : 1);
185 Name[] names = arguments(numRes, basicTypeSignature.substring(0, arity));
186 for (int i = 0; i < numRes; i++) {
187 names[arity + i] = constantZero(arity + i, basicTypeSignature.charAt(resultPos + i));
188 }
189 return names;
190 }
191
192 private static int fixResult(int result, Name[] names) {
193 if (result >= 0) {
194 if (names[result].type == 'V')
195 return -1;
196 } else if (result == LAST_RESULT) {
197 return names.length - 1;
198 }
199 return result;
200 }
201
202 private static boolean namesOK(int arity, Name[] names) {
203 for (int i = 0; i < names.length; i++) {
204 Name n = names[i];
205 assert(n != null) : "n is null";
206 if (i < arity)
207 assert( n.isParam()) : n + " is not param at " + i;
208 else
209 assert(!n.isParam()) : n + " is param at " + i;
210 }
211 return true;
212 }
213
214 /** Renumber and/or replace params so that they are interned and canonically numbered. */
215 private void normalize() {
216 Name[] oldNames = null;
217 int changesStart = 0;
218 for (int i = 0; i < names.length; i++) {
219 Name n = names[i];
220 if (!n.initIndex(i)) {
221 if (oldNames == null) {
222 oldNames = names.clone();
223 changesStart = i;
224 }
225 names[i] = n.cloneWithIndex(i);
226 }
227 }
228 if (oldNames != null) {
229 int startFixing = arity;
230 if (startFixing <= changesStart)
231 startFixing = changesStart+1;
232 for (int i = startFixing; i < names.length; i++) {
233 Name fixed = names[i].replaceNames(oldNames, names, changesStart, i);
234 names[i] = fixed.newIndex(i);
235 }
236 }
237 assert(nameRefsAreLegal());
238 int maxInterned = Math.min(arity, INTERNED_ARGUMENT_LIMIT);
239 boolean needIntern = false;
240 for (int i = 0; i < maxInterned; i++) {
241 Name n = names[i], n2 = internArgument(n);
242 if (n != n2) {
243 names[i] = n2;
244 needIntern = true;
245 }
246 }
247 if (needIntern) {
248 for (int i = arity; i < names.length; i++) {
249 names[i].internArguments();
250 }
251 assert(nameRefsAreLegal());
252 }
253 }
254
255 /**
256 * Check that all embedded Name references are localizable to this lambda,
257 * and are properly ordered after their corresponding definitions.
258 * <p>
259 * Note that a Name can be local to multiple lambdas, as long as
260 * it possesses the same index in each use site.
261 * This allows Name references to be freely reused to construct
262 * fresh lambdas, without confusion.
263 */
264 private boolean nameRefsAreLegal() {
265 assert(arity >= 0 && arity <= names.length);
266 assert(result >= -1 && result < names.length);
267 // Do all names possess an index consistent with their local definition order?
268 for (int i = 0; i < arity; i++) {
269 Name n = names[i];
270 assert(n.index() == i) : Arrays.asList(n.index(), i);
271 assert(n.isParam());
272 }
273 // Also, do all local name references
274 for (int i = arity; i < names.length; i++) {
275 Name n = names[i];
276 assert(n.index() == i);
277 for (Object arg : n.arguments) {
278 if (arg instanceof Name) {
279 Name n2 = (Name) arg;
280 int i2 = n2.index;
281 assert(0 <= i2 && i2 < names.length) : n.debugString() + ": 0 <= i2 && i2 < names.length: 0 <= " + i2 + " < " + names.length;
282 assert(names[i2] == n2) : Arrays.asList("-1-", i, "-2-", n.debugString(), "-3-", i2, "-4-", n2.debugString(), "-5-", names[i2].debugString(), "-6-", this);
283 assert(i2 < i); // ref must come after def!
284 }
285 }
286 }
287 return true;
288 }
289
290 /** Invoke this form on the given arguments. */
291 // final Object invoke(Object... args) throws Throwable {
292 // // NYI: fit this into the fast path?
293 // return interpretWithArguments(args);
294 // }
295
296 /** Report the return type. */
297 char returnType() {
298 if (result < 0) return 'V';
299 Name n = names[result];
300 return n.type;
301 }
302
303 /** Report the N-th argument type. */
304 char parameterType(int n) {
305 assert(n < arity);
306 return names[n].type;
307 }
308
309 /** Report the arity. */
310 int arity() {
311 return arity;
312 }
313
314 /** Return the method type corresponding to my basic type signature. */
315 MethodType methodType() {
316 return signatureType(basicTypeSignature());
317 }
318 /** Return ABC_Z, where the ABC are parameter type characters, and Z is the return type character. */
319 final String basicTypeSignature() {
320 StringBuilder buf = new StringBuilder(arity() + 3);
321 for (int i = 0, a = arity(); i < a; i++)
322 buf.append(parameterType(i));
323 return buf.append('_').append(returnType()).toString();
324 }
325 static int signatureArity(String sig) {
326 assert(isValidSignature(sig));
327 return sig.indexOf('_');
328 }
329 static char signatureReturn(String sig) {
330 return sig.charAt(signatureArity(sig)+1);
331 }
332 static boolean isValidSignature(String sig) {
333 int arity = sig.indexOf('_');
334 if (arity < 0) return false; // must be of the form *_*
335 int siglen = sig.length();
336 if (siglen != arity + 2) return false; // *_X
337 for (int i = 0; i < siglen; i++) {
338 if (i == arity) continue; // skip '_'
339 char c = sig.charAt(i);
340 if (c == 'V')
341 return (i == siglen - 1 && arity == siglen - 2);
342 if (ALL_TYPES.indexOf(c) < 0) return false; // must be [LIJFD]
343 }
344 return true; // [LIJFD]*_[LIJFDV]
345 }
346 static Class<?> typeClass(char t) {
347 switch (t) {
348 case 'I': return int.class;
349 case 'J': return long.class;
350 case 'F': return float.class;
351 case 'D': return double.class;
352 case 'L': return Object.class;
353 case 'V': return void.class;
354 default: assert false;
355 }
356 return null;
357 }
358 static MethodType signatureType(String sig) {
359 Class<?>[] ptypes = new Class<?>[signatureArity(sig)];
360 for (int i = 0; i < ptypes.length; i++)
361 ptypes[i] = typeClass(sig.charAt(i));
362 Class<?> rtype = typeClass(signatureReturn(sig));
363 return MethodType.methodType(rtype, ptypes);
364 }
365
366 /*
367 * Code generation issues:
368 *
369 * Compiled LFs should be reusable in general.
370 * The biggest issue is how to decide when to pull a name into
371 * the bytecode, versus loading a reified form from the MH data.
372 *
373 * For example, an asType wrapper may require execution of a cast
374 * after a call to a MH. The target type of the cast can be placed
375 * as a constant in the LF itself. This will force the cast type
376 * to be compiled into the bytecodes and native code for the MH.
377 * Or, the target type of the cast can be erased in the LF, and
378 * loaded from the MH data. (Later on, if the MH as a whole is
379 * inlined, the data will flow into the inlined instance of the LF,
380 * as a constant, and the end result will be an optimal cast.)
381 *
382 * This erasure of cast types can be done with any use of
383 * reference types. It can also be done with whole method
384 * handles. Erasing a method handle might leave behind
385 * LF code that executes correctly for any MH of a given
386 * type, and load the required MH from the enclosing MH's data.
387 * Or, the erasure might even erase the expected MT.
388 *
389 * Also, for direct MHs, the MemberName of the target
390 * could be erased, and loaded from the containing direct MH.
391 * As a simple case, a LF for all int-valued non-static
392 * field getters would perform a cast on its input argument
393 * (to non-constant base type derived from the MemberName)
394 * and load an integer value from the input object
395 * (at a non-constant offset also derived from the MemberName).
396 * Such MN-erased LFs would be inlinable back to optimized
397 * code, whenever a constant enclosing DMH is available
398 * to supply a constant MN from its data.
399 *
400 * The main problem here is to keep LFs reasonably generic,
401 * while ensuring that hot spots will inline good instances.
402 * "Reasonably generic" means that we don't end up with
403 * repeated versions of bytecode or machine code that do
404 * not differ in their optimized form. Repeated versions
405 * of machine would have the undesirable overheads of
406 * (a) redundant compilation work and (b) extra I$ pressure.
407 * To control repeated versions, we need to be ready to
408 * erase details from LFs and move them into MH data,
409 * whevener those details are not relevant to significant
410 * optimization. "Significant" means optimization of
411 * code that is actually hot.
412 *
413 * Achieving this may require dynamic splitting of MHs, by replacing
414 * a generic LF with a more specialized one, on the same MH,
415 * if (a) the MH is frequently executed and (b) the MH cannot
416 * be inlined into a containing caller, such as an invokedynamic.
417 *
418 * Compiled LFs that are no longer used should be GC-able.
419 * If they contain non-BCP references, they should be properly
420 * interlinked with the class loader(s) that their embedded types
421 * depend on. This probably means that reusable compiled LFs
422 * will be tabulated (indexed) on relevant class loaders,
423 * or else that the tables that cache them will have weak links.
424 */
425
426 /**
427 * Make this LF directly executable, as part of a MethodHandle.
428 * Invariant: Every MH which is invoked must prepare its LF
429 * before invocation.
430 * (In principle, the JVM could do this very lazily,
431 * as a sort of pre-invocation linkage step.)
432 */
433 public void prepare() {
434 if (COMPILE_THRESHOLD == 0) {
435 compileToBytecode();
436 }
437 if (this.vmentry != null) {
438 // already prepared (e.g., a primitive DMH invoker form)
439 return;
440 }
441 LambdaForm prep = getPreparedForm(basicTypeSignature());
442 this.vmentry = prep.vmentry;
443 // TO DO: Maybe add invokeGeneric, invokeWithArguments
444 }
445
446 /** Generate optimizable bytecode for this form. */
447 MemberName compileToBytecode() {
448 MethodType invokerType = methodType();
449 assert(vmentry == null || vmentry.getMethodType().basicType().equals(invokerType));
450 if (vmentry != null && isCompiled) {
451 return vmentry; // already compiled somehow
452 }
453 try {
454 vmentry = InvokerBytecodeGenerator.generateCustomizedCode(this, invokerType);
455 if (TRACE_INTERPRETER)
456 traceInterpreter("compileToBytecode", this);
457 isCompiled = true;
458 return vmentry;
459 } catch (Error | Exception ex) {
460 throw newInternalError("compileToBytecode", ex);
461 }
462 }
463
464 private static final ConcurrentHashMap<String,LambdaForm> PREPARED_FORMS;
465 static {
466 int capacity = 512; // expect many distinct signatures over time
467 float loadFactor = 0.75f; // normal default
468 int writers = 1;
469 PREPARED_FORMS = new ConcurrentHashMap<>(capacity, loadFactor, writers);
470 }
471
472 private static Map<String,LambdaForm> computeInitialPreparedForms() {
473 // Find all predefined invokers and associate them with canonical empty lambda forms.
474 HashMap<String,LambdaForm> forms = new HashMap<>();
475 for (MemberName m : MemberName.getFactory().getMethods(LambdaForm.class, false, null, null, null)) {
476 if (!m.isStatic() || !m.isPackage()) continue;
477 MethodType mt = m.getMethodType();
478 if (mt.parameterCount() > 0 &&
479 mt.parameterType(0) == MethodHandle.class &&
480 m.getName().startsWith("interpret_")) {
481 String sig = basicTypeSignature(mt);
482 assert(m.getName().equals("interpret" + sig.substring(sig.indexOf('_'))));
483 LambdaForm form = new LambdaForm(sig);
484 form.vmentry = m;
485 mt.form().setCachedLambdaForm(MethodTypeForm.LF_COUNTER, form);
486 // FIXME: get rid of PREPARED_FORMS; use MethodTypeForm cache only
487 forms.put(sig, form);
488 }
489 }
490 //System.out.println("computeInitialPreparedForms => "+forms);
491 return forms;
492 }
493
494 // Set this false to disable use of the interpret_L methods defined in this file.
495 private static final boolean USE_PREDEFINED_INTERPRET_METHODS = true;
496
497 // The following are predefined exact invokers. The system must build
498 // a separate invoker for each distinct signature.
499 static Object interpret_L(MethodHandle mh) throws Throwable {
500 Object[] av = {mh};
501 String sig = null;
502 assert(argumentTypesMatch(sig = "L_L", av));
503 Object res = mh.form.interpretWithArguments(av);
504 assert(returnTypesMatch(sig, av, res));
505 return res;
506 }
507 static Object interpret_L(MethodHandle mh, Object x1) throws Throwable {
508 Object[] av = {mh, x1};
509 String sig = null;
510 assert(argumentTypesMatch(sig = "LL_L", av));
511 Object res = mh.form.interpretWithArguments(av);
512 assert(returnTypesMatch(sig, av, res));
513 return res;
514 }
515 static Object interpret_L(MethodHandle mh, Object x1, Object x2) throws Throwable {
516 Object[] av = {mh, x1, x2};
517 String sig = null;
518 assert(argumentTypesMatch(sig = "LLL_L", av));
519 Object res = mh.form.interpretWithArguments(av);
520 assert(returnTypesMatch(sig, av, res));
521 return res;
522 }
523 private static LambdaForm getPreparedForm(String sig) {
524 MethodType mtype = signatureType(sig);
525 //LambdaForm prep = PREPARED_FORMS.get(sig);
526 LambdaForm prep = mtype.form().cachedLambdaForm(MethodTypeForm.LF_INTERPRET);
527 if (prep != null) return prep;
528 assert(isValidSignature(sig));
529 prep = new LambdaForm(sig);
530 prep.vmentry = InvokerBytecodeGenerator.generateLambdaFormInterpreterEntryPoint(sig);
531 //LambdaForm prep2 = PREPARED_FORMS.putIfAbsent(sig.intern(), prep);
532 return mtype.form().setCachedLambdaForm(MethodTypeForm.LF_INTERPRET, prep);
533 }
534
535 // The next few routines are called only from assert expressions
536 // They verify that the built-in invokers process the correct raw data types.
537 private static boolean argumentTypesMatch(String sig, Object[] av) {
538 int arity = signatureArity(sig);
539 assert(av.length == arity) : "av.length == arity: av.length=" + av.length + ", arity=" + arity;
540 assert(av[0] instanceof MethodHandle) : "av[0] not instace of MethodHandle: " + av[0];
541 MethodHandle mh = (MethodHandle) av[0];
542 MethodType mt = mh.type();
543 assert(mt.parameterCount() == arity-1);
544 for (int i = 0; i < av.length; i++) {
545 Class<?> pt = (i == 0 ? MethodHandle.class : mt.parameterType(i-1));
546 assert(valueMatches(sig.charAt(i), pt, av[i]));
547 }
548 return true;
549 }
550 private static boolean valueMatches(char tc, Class<?> type, Object x) {
551 // The following line is needed because (...)void method handles can use non-void invokers
552 if (type == void.class) tc = 'V'; // can drop any kind of value
553 assert tc == basicType(type) : tc + " == basicType(" + type + ")=" + basicType(type);
554 switch (tc) {
555 case 'I': assert checkInt(type, x) : "checkInt(" + type + "," + x +")"; break;
556 case 'J': assert x instanceof Long : "instanceof Long: " + x; break;
557 case 'F': assert x instanceof Float : "instanceof Float: " + x; break;
558 case 'D': assert x instanceof Double : "instanceof Double: " + x; break;
559 case 'L': assert checkRef(type, x) : "checkRef(" + type + "," + x + ")"; break;
560 case 'V': break; // allow anything here; will be dropped
561 default: assert(false);
562 }
563 return true;
564 }
565 private static boolean returnTypesMatch(String sig, Object[] av, Object res) {
566 MethodHandle mh = (MethodHandle) av[0];
567 return valueMatches(signatureReturn(sig), mh.type().returnType(), res);
568 }
569 private static boolean checkInt(Class<?> type, Object x) {
570 assert(x instanceof Integer);
571 if (type == int.class) return true;
572 Wrapper w = Wrapper.forBasicType(type);
573 assert(w.isSubwordOrInt());
574 Object x1 = Wrapper.INT.wrap(w.wrap(x));
575 return x.equals(x1);
576 }
577 private static boolean checkRef(Class<?> type, Object x) {
578 assert(!type.isPrimitive());
579 if (x == null) return true;
580 if (type.isInterface()) return true;
581 return type.isInstance(x);
582 }
583
584 /** If the invocation count hits the threshold we spin bytecodes and call that subsequently. */
585 private static final int COMPILE_THRESHOLD;
586 static {
587 if (MethodHandleStatics.COMPILE_THRESHOLD != null)
588 COMPILE_THRESHOLD = MethodHandleStatics.COMPILE_THRESHOLD;
589 else
590 COMPILE_THRESHOLD = 30; // default value
591 }
592 private int invocationCounter = 0;
593
594 @Hidden
595 @DontInline
596 /** Interpretively invoke this form on the given arguments. */
597 Object interpretWithArguments(Object... argumentValues) throws Throwable {
598 if (TRACE_INTERPRETER)
599 return interpretWithArgumentsTracing(argumentValues);
600 checkInvocationCounter();
601 assert(arityCheck(argumentValues));
602 Object[] values = Arrays.copyOf(argumentValues, names.length);
603 for (int i = argumentValues.length; i < values.length; i++) {
604 values[i] = interpretName(names[i], values);
605 }
606 return (result < 0) ? null : values[result];
607 }
608
609 @Hidden
610 @DontInline
611 /** Evaluate a single Name within this form, applying its function to its arguments. */
612 Object interpretName(Name name, Object[] values) throws Throwable {
613 if (TRACE_INTERPRETER)
614 traceInterpreter("| interpretName", name.debugString(), (Object[]) null);
615 Object[] arguments = Arrays.copyOf(name.arguments, name.arguments.length, Object[].class);
616 for (int i = 0; i < arguments.length; i++) {
617 Object a = arguments[i];
618 if (a instanceof Name) {
619 int i2 = ((Name)a).index();
620 assert(names[i2] == a);
621 a = values[i2];
622 arguments[i] = a;
623 }
624 }
625 return name.function.invokeWithArguments(arguments);
626 }
627
628 private void checkInvocationCounter() {
629 if (COMPILE_THRESHOLD != 0 &&
630 invocationCounter < COMPILE_THRESHOLD) {
631 invocationCounter++; // benign race
632 if (invocationCounter >= COMPILE_THRESHOLD) {
633 // Replace vmentry with a bytecode version of this LF.
634 compileToBytecode();
635 }
636 }
637 }
638 Object interpretWithArgumentsTracing(Object... argumentValues) throws Throwable {
639 traceInterpreter("[ interpretWithArguments", this, argumentValues);
640 if (invocationCounter < COMPILE_THRESHOLD) {
641 int ctr = invocationCounter++; // benign race
642 traceInterpreter("| invocationCounter", ctr);
643 if (invocationCounter >= COMPILE_THRESHOLD) {
644 compileToBytecode();
645 }
646 }
647 Object rval;
648 try {
649 assert(arityCheck(argumentValues));
650 Object[] values = Arrays.copyOf(argumentValues, names.length);
651 for (int i = argumentValues.length; i < values.length; i++) {
652 values[i] = interpretName(names[i], values);
653 }
654 rval = (result < 0) ? null : values[result];
655 } catch (Throwable ex) {
656 traceInterpreter("] throw =>", ex);
657 throw ex;
658 }
659 traceInterpreter("] return =>", rval);
660 return rval;
661 }
662
663 //** This transform is applied (statically) to every name.function. */
664 /*
665 private static MethodHandle eraseSubwordTypes(MethodHandle mh) {
666 MethodType mt = mh.type();
667 if (mt.hasPrimitives()) {
668 mt = mt.changeReturnType(eraseSubwordType(mt.returnType()));
669 for (int i = 0; i < mt.parameterCount(); i++) {
670 mt = mt.changeParameterType(i, eraseSubwordType(mt.parameterType(i)));
671 }
672 mh = MethodHandles.explicitCastArguments(mh, mt);
673 }
674 return mh;
675 }
676 private static Class<?> eraseSubwordType(Class<?> type) {
677 if (!type.isPrimitive()) return type;
678 if (type == int.class) return type;
679 Wrapper w = Wrapper.forPrimitiveType(type);
680 if (w.isSubwordOrInt()) return int.class;
681 return type;
682 }
683 */
684
685 static void traceInterpreter(String event, Object obj, Object... args) {
686 if (TRACE_INTERPRETER) {
687 System.out.println("LFI: "+event+" "+(obj != null ? obj : "")+(args != null && args.length != 0 ? Arrays.asList(args) : ""));
688 }
689 }
690 static void traceInterpreter(String event, Object obj) {
691 traceInterpreter(event, obj, (Object[])null);
692 }
693 private boolean arityCheck(Object[] argumentValues) {
694 assert(argumentValues.length == arity) : arity+"!="+Arrays.asList(argumentValues)+".length";
695 // also check that the leading (receiver) argument is somehow bound to this LF:
696 assert(argumentValues[0] instanceof MethodHandle) : "not MH: " + argumentValues[0];
697 assert(((MethodHandle)argumentValues[0]).internalForm() == this);
698 // note: argument #0 could also be an interface wrapper, in the future
699 return true;
700 }
701
702 private boolean isEmpty() {
703 if (result < 0)
704 return (names.length == arity);
705 else if (result == arity && names.length == arity + 1)
706 return names[arity].isConstantZero();
707 else
708 return false;
709 }
710
711 public String toString() {
712 StringBuilder buf = new StringBuilder(debugName+"=Lambda(");
713 for (int i = 0; i < names.length; i++) {
714 if (i == arity) buf.append(")=>{");
715 Name n = names[i];
716 if (i >= arity) buf.append("\n ");
717 buf.append(n);
718 if (i < arity) {
719 if (i+1 < arity) buf.append(",");
720 continue;
721 }
722 buf.append("=").append(n.exprString());
723 buf.append(";");
724 }
725 buf.append(result < 0 ? "void" : names[result]).append("}");
726 if (TRACE_INTERPRETER) {
727 // Extra verbosity:
728 buf.append(":").append(basicTypeSignature());
729 buf.append("/").append(vmentry);
730 }
731 return buf.toString();
732 }
733
734 /**
735 * Apply immediate binding for a Name in this form indicated by its position relative to the form.
736 * The first parameter to a LambdaForm, a0:L, always represents the form's method handle, so 0 is not
737 * accepted as valid.
738 */
739 LambdaForm bindImmediate(int pos, char basicType, Object value) {
740 // must be an argument, and the types must match
741 assert pos > 0 && pos < arity && names[pos].type == basicType && Name.typesMatch(basicType, value);
742
743 int arity2 = arity - 1;
744 Name[] names2 = new Name[names.length - 1];
745 for (int r = 0, w = 0; r < names.length; ++r, ++w) { // (r)ead from names, (w)rite to names2
746 Name n = names[r];
747 if (n.isParam()) {
748 if (n.index == pos) {
749 // do not copy over the argument that is to be replaced with a literal,
750 // but adjust the write index
751 --w;
752 } else {
753 names2[w] = new Name(w, n.type);
754 }
755 } else {
756 Object[] arguments2 = new Object[n.arguments.length];
757 for (int i = 0; i < n.arguments.length; ++i) {
758 Object arg = n.arguments[i];
759 if (arg instanceof Name) {
760 int ni = ((Name) arg).index;
761 if (ni == pos) {
762 arguments2[i] = value;
763 } else if (ni < pos) {
764 // replacement position not yet passed
765 arguments2[i] = names2[ni];
766 } else {
767 // replacement position passed
768 arguments2[i] = names2[ni - 1];
769 }
770 } else {
771 arguments2[i] = arg;
772 }
773 }
774 names2[w] = new Name(n.function, arguments2);
775 names2[w].initIndex(w);
776 }
777 }
778
779 int result2 = result == -1 ? -1 : result - 1;
780 return new LambdaForm(debugName, arity2, names2, result2);
781 }
782
783 LambdaForm bind(int namePos, BoundMethodHandle.SpeciesData oldData) {
784 Name name = names[namePos];
785 BoundMethodHandle.SpeciesData newData = oldData.extendWithType(name.type);
786 return bind(name, newData.getterName(names[0], oldData.fieldCount()), oldData, newData);
787 }
788 LambdaForm bind(Name name, Name binding,
789 BoundMethodHandle.SpeciesData oldData,
790 BoundMethodHandle.SpeciesData newData) {
791 int pos = name.index;
792 assert(name.isParam());
793 assert(!binding.isParam());
794 assert(name.type == binding.type);
795 assert(0 <= pos && pos < arity && names[pos] == name);
796 assert(binding.function.memberDeclaringClassOrNull() == newData.clazz);
797 assert(oldData.getters.length == newData.getters.length-1);
798 if (bindCache != null) {
799 LambdaForm form = bindCache[pos];
800 if (form != null) {
801 assert(form.contains(binding)) : "form << " + form + " >> does not contain binding << " + binding + " >>";
802 return form;
803 }
804 } else {
805 bindCache = new LambdaForm[arity];
806 }
807 assert(nameRefsAreLegal());
808 int arity2 = arity-1;
809 Name[] names2 = names.clone();
810 names2[pos] = binding; // we might move this in a moment
811
812 // The newly created LF will run with a different BMH.
813 // Switch over any pre-existing BMH field references to the new BMH class.
814 int firstOldRef = -1;
815 for (int i = 0; i < names2.length; i++) {
816 Name n = names[i];
817 if (n.function != null &&
818 n.function.memberDeclaringClassOrNull() == oldData.clazz) {
819 MethodHandle oldGetter = n.function.resolvedHandle;
820 MethodHandle newGetter = null;
821 for (int j = 0; j < oldData.getters.length; j++) {
822 if (oldGetter == oldData.getters[j])
823 newGetter = newData.getters[j];
824 }
825 if (newGetter != null) {
826 if (firstOldRef < 0) firstOldRef = i;
827 Name n2 = new Name(newGetter, n.arguments);
828 names2[i] = n2;
829 }
830 }
831 }
832
833 // Walk over the new list of names once, in forward order.
834 // Replace references to 'name' with 'binding'.
835 // Replace data structure references to the old BMH species with the new.
836 // This might cause a ripple effect, but it will settle in one pass.
837 assert(firstOldRef < 0 || firstOldRef > pos);
838 for (int i = pos+1; i < names2.length; i++) {
839 if (i <= arity2) continue;
840 names2[i] = names2[i].replaceNames(names, names2, pos, i);
841 }
842
843 // (a0, a1, name=a2, a3, a4) => (a0, a1, a3, a4, binding)
844 int insPos = pos;
845 for (; insPos+1 < names2.length; insPos++) {
846 Name n = names2[insPos+1];
847 if (n.isSiblingBindingBefore(binding)) {
848 names2[insPos] = n;
849 } else {
850 break;
851 }
852 }
853 names2[insPos] = binding;
854
855 // Since we moved some stuff, maybe update the result reference:
856 int result2 = result;
857 if (result2 == pos)
858 result2 = insPos;
859 else if (result2 > pos && result2 <= insPos)
860 result2 -= 1;
861
862 return bindCache[pos] = new LambdaForm(debugName, arity2, names2, result2);
863 }
864
865 boolean contains(Name name) {
866 int pos = name.index();
867 if (pos >= 0) {
868 return pos < names.length && name.equals(names[pos]);
869 }
870 for (int i = arity; i < names.length; i++) {
871 if (name.equals(names[i]))
872 return true;
873 }
874 return false;
875 }
876
877 LambdaForm addArguments(int pos, char... types) {
878 assert(pos <= arity);
879 int length = names.length;
880 int inTypes = types.length;
881 Name[] names2 = Arrays.copyOf(names, length + inTypes);
882 int arity2 = arity + inTypes;
883 int result2 = result;
884 if (result2 >= arity)
885 result2 += inTypes;
886 // names array has MH in slot 0; skip it.
887 int argpos = pos + 1;
888 // Note: The LF constructor will rename names2[argpos...].
889 // Make space for new arguments (shift temporaries).
890 System.arraycopy(names, argpos, names2, argpos + inTypes, length - argpos);
891 for (int i = 0; i < inTypes; i++) {
892 names2[argpos + i] = new Name(types[i]);
893 }
894 return new LambdaForm(debugName, arity2, names2, result2);
895 }
896
897 LambdaForm addArguments(int pos, List<Class<?>> types) {
898 char[] basicTypes = new char[types.size()];
899 for (int i = 0; i < basicTypes.length; i++)
900 basicTypes[i] = basicType(types.get(i));
901 return addArguments(pos, basicTypes);
902 }
903
904 LambdaForm permuteArguments(int skip, int[] reorder, char[] types) {
905 // Note: When inArg = reorder[outArg], outArg is fed by a copy of inArg.
906 // The types are the types of the new (incoming) arguments.
907 int length = names.length;
908 int inTypes = types.length;
909 int outArgs = reorder.length;
910 assert(skip+outArgs == arity);
911 assert(permutedTypesMatch(reorder, types, names, skip));
912 int pos = 0;
913 // skip trivial first part of reordering:
914 while (pos < outArgs && reorder[pos] == pos) pos += 1;
915 Name[] names2 = new Name[length - outArgs + inTypes];
916 System.arraycopy(names, 0, names2, 0, skip+pos);
917 // copy the body:
918 int bodyLength = length - arity;
919 System.arraycopy(names, skip+outArgs, names2, skip+inTypes, bodyLength);
920 int arity2 = names2.length - bodyLength;
921 int result2 = result;
922 if (result2 >= 0) {
923 if (result2 < skip+outArgs) {
924 // return the corresponding inArg
925 result2 = reorder[result2-skip];
926 } else {
927 result2 = result2 - outArgs + inTypes;
928 }
929 }
930 // rework names in the body:
931 for (int j = pos; j < outArgs; j++) {
932 Name n = names[skip+j];
933 int i = reorder[j];
934 // replace names[skip+j] by names2[skip+i]
935 Name n2 = names2[skip+i];
936 if (n2 == null)
937 names2[skip+i] = n2 = new Name(types[i]);
938 else
939 assert(n2.type == types[i]);
940 for (int k = arity2; k < names2.length; k++) {
941 names2[k] = names2[k].replaceName(n, n2);
942 }
943 }
944 // some names are unused, but must be filled in
945 for (int i = skip+pos; i < arity2; i++) {
946 if (names2[i] == null)
947 names2[i] = argument(i, types[i - skip]);
948 }
949 for (int j = arity; j < names.length; j++) {
950 int i = j - arity + arity2;
951 // replace names2[i] by names[j]
952 Name n = names[j];
953 Name n2 = names2[i];
954 if (n != n2) {
955 for (int k = i+1; k < names2.length; k++) {
956 names2[k] = names2[k].replaceName(n, n2);
957 }
958 }
959 }
960 return new LambdaForm(debugName, arity2, names2, result2);
961 }
962
963 static boolean permutedTypesMatch(int[] reorder, char[] types, Name[] names, int skip) {
964 int inTypes = types.length;
965 int outArgs = reorder.length;
966 for (int i = 0; i < outArgs; i++) {
967 assert(names[skip+i].isParam());
968 assert(names[skip+i].type == types[reorder[i]]);
969 }
970 return true;
971 }
972
973 static class NamedFunction {
974 final MemberName member;
975 @Stable MethodHandle resolvedHandle;
976 @Stable MethodHandle invoker;
977
978 NamedFunction(MethodHandle resolvedHandle) {
979 this(resolvedHandle.internalMemberName(), resolvedHandle);
980 }
981 NamedFunction(MemberName member, MethodHandle resolvedHandle) {
982 this.member = member;
983 //resolvedHandle = eraseSubwordTypes(resolvedHandle);
984 this.resolvedHandle = resolvedHandle;
985 }
986 NamedFunction(MethodType basicInvokerType) {
987 assert(basicInvokerType == basicInvokerType.basicType()) : basicInvokerType;
988 if (basicInvokerType.parameterSlotCount() < MethodType.MAX_MH_INVOKER_ARITY) {
989 this.resolvedHandle = basicInvokerType.invokers().basicInvoker();
990 this.member = resolvedHandle.internalMemberName();
991 } else {
992 // necessary to pass BigArityTest
993 this.member = Invokers.invokeBasicMethod(basicInvokerType);
994 }
995 }
996
997 // The next 3 constructors are used to break circular dependencies on MH.invokeStatic, etc.
998 // Any LambdaForm containing such a member is not interpretable.
999 // This is OK, since all such LFs are prepared with special primitive vmentry points.
1000 // And even without the resolvedHandle, the name can still be compiled and optimized.
1001 NamedFunction(Method method) {
1002 this(new MemberName(method));
1003 }
1004 NamedFunction(Field field) {
1005 this(new MemberName(field));
1006 }
1007 NamedFunction(MemberName member) {
1008 this.member = member;
1009 this.resolvedHandle = null;
1010 }
1011
1012 MethodHandle resolvedHandle() {
1013 if (resolvedHandle == null) resolve();
1014 return resolvedHandle;
1015 }
1016
1017 void resolve() {
1018 resolvedHandle = DirectMethodHandle.make(member);
1019 }
1020
1021 @Override
1022 public boolean equals(Object other) {
1023 if (this == other) return true;
1024 if (other == null) return false;
1025 if (!(other instanceof NamedFunction)) return false;
1026 NamedFunction that = (NamedFunction) other;
1027 return this.member != null && this.member.equals(that.member);
1028 }
1029
1030 @Override
1031 public int hashCode() {
1032 if (member != null)
1033 return member.hashCode();
1034 return super.hashCode();
1035 }
1036
1037 // Put the predefined NamedFunction invokers into the table.
1038 static void initializeInvokers() {
1039 for (MemberName m : MemberName.getFactory().getMethods(NamedFunction.class, false, null, null, null)) {
1040 if (!m.isStatic() || !m.isPackage()) continue;
1041 MethodType type = m.getMethodType();
1042 if (type.equals(INVOKER_METHOD_TYPE) &&
1043 m.getName().startsWith("invoke_")) {
1044 String sig = m.getName().substring("invoke_".length());
1045 int arity = LambdaForm.signatureArity(sig);
1046 MethodType srcType = MethodType.genericMethodType(arity);
1047 if (LambdaForm.signatureReturn(sig) == 'V')
1048 srcType = srcType.changeReturnType(void.class);
1049 MethodTypeForm typeForm = srcType.form();
1050 typeForm.namedFunctionInvoker = DirectMethodHandle.make(m);
1051 }
1052 }
1053 }
1054
1055 // The following are predefined NamedFunction invokers. The system must build
1056 // a separate invoker for each distinct signature.
1057 /** void return type invokers. */
1058 @Hidden
1059 static Object invoke__V(MethodHandle mh, Object[] a) throws Throwable {
1060 assert(a.length == 0);
1061 mh.invokeBasic();
1062 return null;
1063 }
1064 @Hidden
1065 static Object invoke_L_V(MethodHandle mh, Object[] a) throws Throwable {
1066 assert(a.length == 1);
1067 mh.invokeBasic(a[0]);
1068 return null;
1069 }
1070 @Hidden
1071 static Object invoke_LL_V(MethodHandle mh, Object[] a) throws Throwable {
1072 assert(a.length == 2);
1073 mh.invokeBasic(a[0], a[1]);
1074 return null;
1075 }
1076 @Hidden
1077 static Object invoke_LLL_V(MethodHandle mh, Object[] a) throws Throwable {
1078 assert(a.length == 3);
1079 mh.invokeBasic(a[0], a[1], a[2]);
1080 return null;
1081 }
1082 @Hidden
1083 static Object invoke_LLLL_V(MethodHandle mh, Object[] a) throws Throwable {
1084 assert(a.length == 4);
1085 mh.invokeBasic(a[0], a[1], a[2], a[3]);
1086 return null;
1087 }
1088 @Hidden
1089 static Object invoke_LLLLL_V(MethodHandle mh, Object[] a) throws Throwable {
1090 assert(a.length == 5);
1091 mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]);
1092 return null;
1093 }
1094 /** Object return type invokers. */
1095 @Hidden
1096 static Object invoke__L(MethodHandle mh, Object[] a) throws Throwable {
1097 assert(a.length == 0);
1098 return mh.invokeBasic();
1099 }
1100 @Hidden
1101 static Object invoke_L_L(MethodHandle mh, Object[] a) throws Throwable {
1102 assert(a.length == 1);
1103 return mh.invokeBasic(a[0]);
1104 }
1105 @Hidden
1106 static Object invoke_LL_L(MethodHandle mh, Object[] a) throws Throwable {
1107 assert(a.length == 2);
1108 return mh.invokeBasic(a[0], a[1]);
1109 }
1110 @Hidden
1111 static Object invoke_LLL_L(MethodHandle mh, Object[] a) throws Throwable {
1112 assert(a.length == 3);
1113 return mh.invokeBasic(a[0], a[1], a[2]);
1114 }
1115 @Hidden
1116 static Object invoke_LLLL_L(MethodHandle mh, Object[] a) throws Throwable {
1117 assert(a.length == 4);
1118 return mh.invokeBasic(a[0], a[1], a[2], a[3]);
1119 }
1120 @Hidden
1121 static Object invoke_LLLLL_L(MethodHandle mh, Object[] a) throws Throwable {
1122 assert(a.length == 5);
1123 return mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]);
1124 }
1125
1126 static final MethodType INVOKER_METHOD_TYPE =
1127 MethodType.methodType(Object.class, MethodHandle.class, Object[].class);
1128
1129 private static MethodHandle computeInvoker(MethodTypeForm typeForm) {
1130 MethodHandle mh = typeForm.namedFunctionInvoker;
1131 if (mh != null) return mh;
1132 MemberName invoker = InvokerBytecodeGenerator.generateNamedFunctionInvoker(typeForm); // this could take a while
1133 mh = DirectMethodHandle.make(invoker);
1134 MethodHandle mh2 = typeForm.namedFunctionInvoker;
1135 if (mh2 != null) return mh2; // benign race
1136 if (!mh.type().equals(INVOKER_METHOD_TYPE))
1137 throw new InternalError(mh.debugString());
1138 return typeForm.namedFunctionInvoker = mh;
1139 }
1140
1141 @Hidden
1142 Object invokeWithArguments(Object... arguments) throws Throwable {
1143 // If we have a cached invoker, call it right away.
1144 // NOTE: The invoker always returns a reference value.
1145 if (TRACE_INTERPRETER) return invokeWithArgumentsTracing(arguments);
1146 assert(checkArgumentTypes(arguments, methodType()));
1147 return invoker().invokeBasic(resolvedHandle(), arguments);
1148 }
1149
1150 @Hidden
1151 Object invokeWithArgumentsTracing(Object[] arguments) throws Throwable {
1152 Object rval;
1153 try {
1154 traceInterpreter("[ call", this, arguments);
1155 if (invoker == null) {
1156 traceInterpreter("| getInvoker", this);
1157 invoker();
1158 }
1159 if (resolvedHandle == null) {
1160 traceInterpreter("| resolve", this);
1161 resolvedHandle();
1162 }
1163 assert(checkArgumentTypes(arguments, methodType()));
1164 rval = invoker().invokeBasic(resolvedHandle(), arguments);
1165 } catch (Throwable ex) {
1166 traceInterpreter("] throw =>", ex);
1167 throw ex;
1168 }
1169 traceInterpreter("] return =>", rval);
1170 return rval;
1171 }
1172
1173 private MethodHandle invoker() {
1174 if (invoker != null) return invoker;
1175 // Get an invoker and cache it.
1176 return invoker = computeInvoker(methodType().form());
1177 }
1178
1179 private static boolean checkArgumentTypes(Object[] arguments, MethodType methodType) {
1180 if (true) return true; // FIXME
1181 MethodType dstType = methodType.form().erasedType();
1182 MethodType srcType = dstType.basicType().wrap();
1183 Class<?>[] ptypes = new Class<?>[arguments.length];
1184 for (int i = 0; i < arguments.length; i++) {
1185 Object arg = arguments[i];
1186 Class<?> ptype = arg == null ? Object.class : arg.getClass();
1187 // If the dest. type is a primitive we keep the
1188 // argument type.
1189 ptypes[i] = dstType.parameterType(i).isPrimitive() ? ptype : Object.class;
1190 }
1191 MethodType argType = MethodType.methodType(srcType.returnType(), ptypes).wrap();
1192 assert(argType.isConvertibleTo(srcType)) : "wrong argument types: cannot convert " + argType + " to " + srcType;
1193 return true;
1194 }
1195
1196 String basicTypeSignature() {
1197 //return LambdaForm.basicTypeSignature(resolvedHandle.type());
1198 return LambdaForm.basicTypeSignature(methodType());
1199 }
1200
1201 MethodType methodType() {
1202 if (resolvedHandle != null)
1203 return resolvedHandle.type();
1204 else
1205 // only for certain internal LFs during bootstrapping
1206 return member.getInvocationType();
1207 }
1208
1209 MemberName member() {
1210 assert(assertMemberIsConsistent());
1211 return member;
1212 }
1213
1214 // Called only from assert.
1215 private boolean assertMemberIsConsistent() {
1216 if (resolvedHandle instanceof DirectMethodHandle) {
1217 MemberName m = resolvedHandle.internalMemberName();
1218 assert(m.equals(member));
1219 }
1220 return true;
1221 }
1222
1223 Class<?> memberDeclaringClassOrNull() {
1224 return (member == null) ? null : member.getDeclaringClass();
1225 }
1226
1227 char returnType() {
1228 return basicType(methodType().returnType());
1229 }
1230
1231 char parameterType(int n) {
1232 return basicType(methodType().parameterType(n));
1233 }
1234
1235 int arity() {
1236 //int siglen = member.getMethodType().parameterCount();
1237 //if (!member.isStatic()) siglen += 1;
1238 //return siglen;
1239 return methodType().parameterCount();
1240 }
1241
1242 public String toString() {
1243 if (member == null) return String.valueOf(resolvedHandle);
1244 return member.getDeclaringClass().getSimpleName()+"."+member.getName();
1245 }
1246 }
1247
1248 void resolve() {
1249 for (Name n : names) n.resolve();
1250 }
1251
1252 public static char basicType(Class<?> type) {
1253 char c = Wrapper.basicTypeChar(type);
1254 if ("ZBSC".indexOf(c) >= 0) c = 'I';
1255 assert("LIJFDV".indexOf(c) >= 0);
1256 return c;
1257 }
1258 public static char[] basicTypes(List<Class<?>> types) {
1259 char[] btypes = new char[types.size()];
1260 for (int i = 0; i < btypes.length; i++) {
1261 btypes[i] = basicType(types.get(i));
1262 }
1263 return btypes;
1264 }
1265 public static String basicTypeSignature(MethodType type) {
1266 char[] sig = new char[type.parameterCount() + 2];
1267 int sigp = 0;
1268 for (Class<?> pt : type.parameterList()) {
1269 sig[sigp++] = basicType(pt);
1270 }
1271 sig[sigp++] = '_';
1272 sig[sigp++] = basicType(type.returnType());
1273 assert(sigp == sig.length);
1274 return String.valueOf(sig);
1275 }
1276
1277 static final class Name {
1278 final char type;
1279 private short index;
1280 final NamedFunction function;
1281 @Stable final Object[] arguments;
1282
1283 private Name(int index, char type, NamedFunction function, Object[] arguments) {
1284 this.index = (short)index;
1285 this.type = type;
1286 this.function = function;
1287 this.arguments = arguments;
1288 assert(this.index == index);
1289 }
1290 Name(MethodHandle function, Object... arguments) {
1291 this(new NamedFunction(function), arguments);
1292 }
1293 Name(MethodType functionType, Object... arguments) {
1294 this(new NamedFunction(functionType), arguments);
1295 assert(arguments[0] instanceof Name && ((Name)arguments[0]).type == 'L');
1296 }
1297 Name(MemberName function, Object... arguments) {
1298 this(new NamedFunction(function), arguments);
1299 }
1300 Name(NamedFunction function, Object... arguments) {
1301 this(-1, function.returnType(), function, arguments = arguments.clone());
1302 assert(arguments.length == function.arity()) : "arity mismatch: arguments.length=" + arguments.length + " == function.arity()=" + function.arity() + " in " + debugString();
1303 for (int i = 0; i < arguments.length; i++)
1304 assert(typesMatch(function.parameterType(i), arguments[i])) : "types don't match: function.parameterType(" + i + ")=" + function.parameterType(i) + ", arguments[" + i + "]=" + arguments[i] + " in " + debugString();
1305 }
1306 Name(int index, char type) {
1307 this(index, type, null, null);
1308 }
1309 Name(char type) {
1310 this(-1, type);
1311 }
1312
1313 char type() { return type; }
1314 int index() { return index; }
1315 boolean initIndex(int i) {
1316 if (index != i) {
1317 if (index != -1) return false;
1318 index = (short)i;
1319 }
1320 return true;
1321 }
1322
1323
1324 void resolve() {
1325 if (function != null)
1326 function.resolve();
1327 }
1328
1329 Name newIndex(int i) {
1330 if (initIndex(i)) return this;
1331 return cloneWithIndex(i);
1332 }
1333 Name cloneWithIndex(int i) {
1334 Object[] newArguments = (arguments == null) ? null : arguments.clone();
1335 return new Name(i, type, function, newArguments);
1336 }
1337 Name replaceName(Name oldName, Name newName) { // FIXME: use replaceNames uniformly
1338 if (oldName == newName) return this;
1339 @SuppressWarnings("LocalVariableHidesMemberVariable")
1340 Object[] arguments = this.arguments;
1341 if (arguments == null) return this;
1342 boolean replaced = false;
1343 for (int j = 0; j < arguments.length; j++) {
1344 if (arguments[j] == oldName) {
1345 if (!replaced) {
1346 replaced = true;
1347 arguments = arguments.clone();
1348 }
1349 arguments[j] = newName;
1350 }
1351 }
1352 if (!replaced) return this;
1353 return new Name(function, arguments);
1354 }
1355 Name replaceNames(Name[] oldNames, Name[] newNames, int start, int end) {
1356 @SuppressWarnings("LocalVariableHidesMemberVariable")
1357 Object[] arguments = this.arguments;
1358 boolean replaced = false;
1359 eachArg:
1360 for (int j = 0; j < arguments.length; j++) {
1361 if (arguments[j] instanceof Name) {
1362 Name n = (Name) arguments[j];
1363 int check = n.index;
1364 // harmless check to see if the thing is already in newNames:
1365 if (check >= 0 && check < newNames.length && n == newNames[check])
1366 continue eachArg;
1367 // n might not have the correct index: n != oldNames[n.index].
1368 for (int i = start; i < end; i++) {
1369 if (n == oldNames[i]) {
1370 if (n == newNames[i])
1371 continue eachArg;
1372 if (!replaced) {
1373 replaced = true;
1374 arguments = arguments.clone();
1375 }
1376 arguments[j] = newNames[i];
1377 continue eachArg;
1378 }
1379 }
1380 }
1381 }
1382 if (!replaced) return this;
1383 return new Name(function, arguments);
1384 }
1385 void internArguments() {
1386 @SuppressWarnings("LocalVariableHidesMemberVariable")
1387 Object[] arguments = this.arguments;
1388 for (int j = 0; j < arguments.length; j++) {
1389 if (arguments[j] instanceof Name) {
1390 Name n = (Name) arguments[j];
1391 if (n.isParam() && n.index < INTERNED_ARGUMENT_LIMIT)
1392 arguments[j] = internArgument(n);
1393 }
1394 }
1395 }
1396 boolean isParam() {
1397 return function == null;
1398 }
1399 boolean isConstantZero() {
1400 return !isParam() && arguments.length == 0 && function.equals(constantZero(0, type).function);
1401 }
1402
1403 public String toString() {
1404 return (isParam()?"a":"t")+(index >= 0 ? index : System.identityHashCode(this))+":"+type;
1405 }
1406 public String debugString() {
1407 String s = toString();
1408 return (function == null) ? s : s + "=" + exprString();
1409 }
1410 public String exprString() {
1411 if (function == null) return "null";
1412 StringBuilder buf = new StringBuilder(function.toString());
1413 buf.append("(");
1414 String cma = "";
1415 for (Object a : arguments) {
1416 buf.append(cma); cma = ",";
1417 if (a instanceof Name || a instanceof Integer)
1418 buf.append(a);
1419 else
1420 buf.append("(").append(a).append(")");
1421 }
1422 buf.append(")");
1423 return buf.toString();
1424 }
1425
1426 private static boolean typesMatch(char parameterType, Object object) {
1427 if (object instanceof Name) {
1428 return ((Name)object).type == parameterType;
1429 }
1430 switch (parameterType) {
1431 case 'I': return object instanceof Integer;
1432 case 'J': return object instanceof Long;
1433 case 'F': return object instanceof Float;
1434 case 'D': return object instanceof Double;
1435 }
1436 assert(parameterType == 'L');
1437 return true;
1438 }
1439
1440 /**
1441 * Does this Name precede the given binding node in some canonical order?
1442 * This predicate is used to order data bindings (via insertion sort)
1443 * with some stability.
1444 */
1445 boolean isSiblingBindingBefore(Name binding) {
1446 assert(!binding.isParam());
1447 if (isParam()) return true;
1448 if (function.equals(binding.function) &&
1449 arguments.length == binding.arguments.length) {
1450 boolean sawInt = false;
1451 for (int i = 0; i < arguments.length; i++) {
1452 Object a1 = arguments[i];
1453 Object a2 = binding.arguments[i];
1454 if (!a1.equals(a2)) {
1455 if (a1 instanceof Integer && a2 instanceof Integer) {
1456 if (sawInt) continue;
1457 sawInt = true;
1458 if ((int)a1 < (int)a2) continue; // still might be true
1459 }
1460 return false;
1461 }
1462 }
1463 return sawInt;
1464 }
1465 return false;
1466 }
1467
1468 /** Return the index of the last occurrence of n in the argument array.
1469 * Return -1 if the name is not used.
1470 */
1471 int lastUseIndex(Name n) {
1472 if (arguments == null) return -1;
1473 for (int i = arguments.length; --i >= 0; ) {
1474 if (arguments[i] == n) return i;
1475 }
1476 return -1;
1477 }
1478
1479 /** Return the number of occurrences of n in the argument array.
1480 * Return 0 if the name is not used.
1481 */
1482 int useCount(Name n) {
1483 if (arguments == null) return 0;
1484 int count = 0;
1485 for (int i = arguments.length; --i >= 0; ) {
1486 if (arguments[i] == n) ++count;
1487 }
1488 return count;
1489 }
1490
1491 boolean contains(Name n) {
1492 return this == n || lastUseIndex(n) >= 0;
1493 }
1494
1495 public boolean equals(Name that) {
1496 if (this == that) return true;
1497 if (isParam())
1498 // each parameter is a unique atom
1499 return false; // this != that
1500 return
1501 //this.index == that.index &&
1502 this.type == that.type &&
1503 this.function.equals(that.function) &&
1504 Arrays.equals(this.arguments, that.arguments);
1505 }
1506 @Override
1507 public boolean equals(Object x) {
1508 return x instanceof Name && equals((Name)x);
1509 }
1510 @Override
1511 public int hashCode() {
1512 if (isParam())
1513 return index | (type << 8);
1514 return function.hashCode() ^ Arrays.hashCode(arguments);
1515 }
1516 }
1517
1518 /** Return the index of the last name which contains n as an argument.
1519 * Return -1 if the name is not used. Return names.length if it is the return value.
1520 */
1521 int lastUseIndex(Name n) {
1522 int ni = n.index, nmax = names.length;
1523 assert(names[ni] == n);
1524 if (result == ni) return nmax; // live all the way beyond the end
1525 for (int i = nmax; --i > ni; ) {
1526 if (names[i].lastUseIndex(n) >= 0)
1527 return i;
1528 }
1529 return -1;
1530 }
1531
1532 /** Return the number of times n is used as an argument or return value. */
1533 int useCount(Name n) {
1534 int ni = n.index, nmax = names.length;
1535 int end = lastUseIndex(n);
1536 if (end < 0) return 0;
1537 int count = 0;
1538 if (end == nmax) { count++; end--; }
1539 int beg = n.index() + 1;
1540 if (beg < arity) beg = arity;
1541 for (int i = beg; i <= end; i++) {
1542 count += names[i].useCount(n);
1543 }
1544 return count;
1545 }
1546
1547 static Name argument(int which, char type) {
1548 int tn = ALL_TYPES.indexOf(type);
1549 if (tn < 0 || which >= INTERNED_ARGUMENT_LIMIT)
1550 return new Name(which, type);
1551 return INTERNED_ARGUMENTS[tn][which];
1552 }
1553 static Name internArgument(Name n) {
1554 assert(n.isParam()) : "not param: " + n;
1555 assert(n.index < INTERNED_ARGUMENT_LIMIT);
1556 return argument(n.index, n.type);
1557 }
1558 static Name[] arguments(int extra, String types) {
1559 int length = types.length();
1560 Name[] names = new Name[length + extra];
1561 for (int i = 0; i < length; i++)
1562 names[i] = argument(i, types.charAt(i));
1563 return names;
1564 }
1565 static Name[] arguments(int extra, char... types) {
1566 int length = types.length;
1567 Name[] names = new Name[length + extra];
1568 for (int i = 0; i < length; i++)
1569 names[i] = argument(i, types[i]);
1570 return names;
1571 }
1572 static Name[] arguments(int extra, List<Class<?>> types) {
1573 int length = types.size();
1574 Name[] names = new Name[length + extra];
1575 for (int i = 0; i < length; i++)
1576 names[i] = argument(i, basicType(types.get(i)));
1577 return names;
1578 }
1579 static Name[] arguments(int extra, Class<?>... types) {
1580 int length = types.length;
1581 Name[] names = new Name[length + extra];
1582 for (int i = 0; i < length; i++)
1583 names[i] = argument(i, basicType(types[i]));
1584 return names;
1585 }
1586 static Name[] arguments(int extra, MethodType types) {
1587 int length = types.parameterCount();
1588 Name[] names = new Name[length + extra];
1589 for (int i = 0; i < length; i++)
1590 names[i] = argument(i, basicType(types.parameterType(i)));
1591 return names;
1592 }
1593 static final String ALL_TYPES = "LIJFD"; // omit V, not an argument type
1594 static final int INTERNED_ARGUMENT_LIMIT = 10;
1595 private static final Name[][] INTERNED_ARGUMENTS
1596 = new Name[ALL_TYPES.length()][INTERNED_ARGUMENT_LIMIT];
1597 static {
1598 for (int tn = 0; tn < ALL_TYPES.length(); tn++) {
1599 for (int i = 0; i < INTERNED_ARGUMENTS[tn].length; i++) {
1600 char type = ALL_TYPES.charAt(tn);
1601 INTERNED_ARGUMENTS[tn][i] = new Name(i, type);
1602 }
1603 }
1604 }
1605
1606 private static final MemberName.Factory IMPL_NAMES = MemberName.getFactory();
1607
1608 static Name constantZero(int which, char type) {
1609 return CONSTANT_ZERO[ALL_TYPES.indexOf(type)].newIndex(which);
1610 }
1611 private static final Name[] CONSTANT_ZERO
1612 = new Name[ALL_TYPES.length()];
1613 static {
1614 for (int tn = 0; tn < ALL_TYPES.length(); tn++) {
1615 char bt = ALL_TYPES.charAt(tn);
1616 Wrapper wrap = Wrapper.forBasicType(bt);
1617 MemberName zmem = new MemberName(LambdaForm.class, "zero"+bt, MethodType.methodType(wrap.primitiveType()), REF_invokeStatic);
1618 try {
1619 zmem = IMPL_NAMES.resolveOrFail(REF_invokeStatic, zmem, null, NoSuchMethodException.class);
1620 } catch (IllegalAccessException|NoSuchMethodException ex) {
1621 throw newInternalError(ex);
1622 }
1623 NamedFunction zcon = new NamedFunction(zmem);
1624 Name n = new Name(zcon).newIndex(0);
1625 assert(n.type == ALL_TYPES.charAt(tn));
1626 CONSTANT_ZERO[tn] = n;
1627 assert(n.isConstantZero());
1628 }
1629 }
1630
1631 // Avoid appealing to ValueConversions at bootstrap time:
1632 private static int zeroI() { return 0; }
1633 private static long zeroJ() { return 0; }
1634 private static float zeroF() { return 0; }
1635 private static double zeroD() { return 0; }
1636 private static Object zeroL() { return null; }
1637
1638 // Put this last, so that previous static inits can run before.
1639 static {
1640 if (USE_PREDEFINED_INTERPRET_METHODS)
1641 PREPARED_FORMS.putAll(computeInitialPreparedForms());
1642 }
1643
1644 /**
1645 * Internal marker for byte-compiled LambdaForms.
1646 */
1647 /*non-public*/
1648 @Target(ElementType.METHOD)
1649 @Retention(RetentionPolicy.RUNTIME)
1650 @interface Compiled {
1651 }
1652
1653 /**
1654 * Internal marker for LambdaForm interpreter frames.
1655 */
1656 /*non-public*/
1657 @Target(ElementType.METHOD)
1658 @Retention(RetentionPolicy.RUNTIME)
1659 @interface Hidden {
1660 }
1661
1662
1663 /*
1664 // Smoke-test for the invokers used in this file.
1665 static void testMethodHandleLinkers() throws Throwable {
1666 MemberName.Factory lookup = MemberName.getFactory();
1667 MemberName asList_MN = new MemberName(Arrays.class, "asList",
1668 MethodType.methodType(List.class, Object[].class),
1669 REF_invokeStatic);
1670 //MethodHandleNatives.resolve(asList_MN, null);
1671 asList_MN = lookup.resolveOrFail(asList_MN, REF_invokeStatic, null, NoSuchMethodException.class);
1672 System.out.println("about to call "+asList_MN);
1673 Object[] abc = { "a", "bc" };
1674 List<?> lst = (List<?>) MethodHandle.linkToStatic(abc, asList_MN);
1675 System.out.println("lst="+lst);
1676 MemberName toString_MN = new MemberName(Object.class.getMethod("toString"));
1677 String s1 = (String) MethodHandle.linkToVirtual(lst, toString_MN);
1678 toString_MN = new MemberName(Object.class.getMethod("toString"), true);
1679 String s2 = (String) MethodHandle.linkToSpecial(lst, toString_MN);
1680 System.out.println("[s1,s2,lst]="+Arrays.asList(s1, s2, lst.toString()));
1681 MemberName toArray_MN = new MemberName(List.class.getMethod("toArray"));
1682 Object[] arr = (Object[]) MethodHandle.linkToInterface(lst, toArray_MN);
1683 System.out.println("toArray="+Arrays.toString(arr));
1684 }
1685 static { try { testMethodHandleLinkers(); } catch (Throwable ex) { throw new RuntimeException(ex); } }
1686 // Requires these definitions in MethodHandle:
1687 static final native Object linkToStatic(Object x1, MemberName mn) throws Throwable;
1688 static final native Object linkToVirtual(Object x1, MemberName mn) throws Throwable;
1689 static final native Object linkToSpecial(Object x1, MemberName mn) throws Throwable;
1690 static final native Object linkToInterface(Object x1, MemberName mn) throws Throwable;
1691 */
1692
1693 static { NamedFunction.initializeInvokers(); }
1694
1695 // The following hack is necessary in order to suppress TRACE_INTERPRETER
1696 // during execution of the static initializes of this class.
1697 // Turning on TRACE_INTERPRETER too early will cause
1698 // stack overflows and other misbehavior during attempts to trace events
1699 // that occur during LambdaForm.<clinit>.
1700 // Therefore, do not move this line higher in this file, and do not remove.
1701 private static final boolean TRACE_INTERPRETER = MethodHandleStatics.TRACE_INTERPRETER;
1702 }