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.HashMap;
34 import java.util.concurrent.ConcurrentHashMap;
35 import sun.invoke.util.Wrapper;
36 import java.lang.reflect.Field;
37
38 import static java.lang.invoke.LambdaForm.BasicType.*;
39 import static java.lang.invoke.MethodHandleStatics.*;
40 import static java.lang.invoke.MethodHandleNatives.Constants.*;
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 public enum BasicType {
134 L_TYPE('L', Object.class, Wrapper.OBJECT), // all reference types
135 I_TYPE('I', int.class, Wrapper.INT),
136 J_TYPE('J', long.class, Wrapper.LONG),
137 F_TYPE('F', float.class, Wrapper.FLOAT),
138 D_TYPE('D', double.class, Wrapper.DOUBLE), // all primitive types
139 V_TYPE('V', void.class, Wrapper.VOID); // not valid in all contexts
140
141 public static final BasicType[] ALL_TYPES = { L_TYPE, I_TYPE, J_TYPE, F_TYPE, D_TYPE, V_TYPE };
142 public static final BasicType[] ARG_TYPES = { L_TYPE, I_TYPE, J_TYPE, F_TYPE, D_TYPE };
143
144 public static final int ARG_TYPE_LIMIT = V_TYPE.ordinal();
145 public static final int TYPE_LIMIT = ARG_TYPE_LIMIT+1;
146
147 private final char btChar;
148 private final Class<?> btClass;
149 private final Wrapper btWrapper;
150
151 private BasicType(char btChar, Class<?> btClass, Wrapper wrapper) {
152 this.btChar = btChar;
153 this.btClass = btClass;
154 this.btWrapper = wrapper;
155 }
156
157 public char basicTypeChar() {
158 return btChar;
159 }
160 public Class<?> basicTypeClass() {
161 return btClass;
162 }
163 public Wrapper basicTypeWrapper() {
164 return btWrapper;
165 }
166 public int basicTypeSlots() {
167 return btWrapper.stackSlots();
168 }
169
170 public static BasicType basicType(byte type) {
171 return ALL_TYPES[type];
172 }
173 public static BasicType basicType(char type) {
174 switch (type) {
175 case 'L': return L_TYPE;
176 case 'I': return I_TYPE;
177 case 'J': return J_TYPE;
178 case 'F': return F_TYPE;
179 case 'D': return D_TYPE;
180 case 'V': return V_TYPE;
181 // all subword types are represented as ints
182 case 'Z':
183 case 'B':
184 case 'S':
185 case 'C':
186 return I_TYPE;
187 default:
188 throw newInternalError("Unknown type char: '"+type+"'");
189 }
190 }
191 public static BasicType basicType(Wrapper type) {
192 char c = type.basicTypeChar();
193 return basicType(c);
194 }
195 public static BasicType basicType(Class<?> type) {
196 if (!type.isPrimitive()) return L_TYPE;
197 return basicType(Wrapper.forPrimitiveType(type));
198 }
199
200 public static char basicTypeChar(Class<?> type) {
201 return basicType(type).btChar;
202 }
203 public static BasicType[] basicTypes(List<Class<?>> types) {
204 BasicType[] btypes = new BasicType[types.size()];
205 for (int i = 0; i < btypes.length; i++) {
206 btypes[i] = basicType(types.get(i));
207 }
208 return btypes;
209 }
210 public static BasicType[] basicTypes(String types) {
211 BasicType[] btypes = new BasicType[types.length()];
212 for (int i = 0; i < btypes.length; i++) {
213 btypes[i] = basicType(types.charAt(i));
214 }
215 return btypes;
216 }
217 public static boolean isBasicTypeChar(char c) {
218 return "LIJFDV".indexOf(c) >= 0;
219 }
220 public static boolean isArgBasicTypeChar(char c) {
221 return "LIJFD".indexOf(c) >= 0;
222 }
223 }
224
225 LambdaForm(String debugName,
226 int arity, Name[] names, int result) {
227 assert(namesOK(arity, names));
228 this.arity = arity;
229 this.result = fixResult(result, names);
230 this.names = names.clone();
231 this.debugName = fixDebugName(debugName);
232 normalize();
233 }
234
235 LambdaForm(String debugName,
236 int arity, Name[] names) {
237 this(debugName,
238 arity, names, LAST_RESULT);
239 }
240
241 LambdaForm(String debugName,
242 Name[] formals, Name[] temps, Name result) {
243 this(debugName,
244 formals.length, buildNames(formals, temps, result), LAST_RESULT);
245 }
246
247 private static Name[] buildNames(Name[] formals, Name[] temps, Name result) {
248 int arity = formals.length;
249 int length = arity + temps.length + (result == null ? 0 : 1);
250 Name[] names = Arrays.copyOf(formals, length);
251 System.arraycopy(temps, 0, names, arity, temps.length);
252 if (result != null)
253 names[length - 1] = result;
254 return names;
255 }
256
257 private LambdaForm(String sig) {
258 // Make a blank lambda form, which returns a constant zero or null.
259 // It is used as a template for managing the invocation of similar forms that are non-empty.
260 // Called only from getPreparedForm.
261 assert(isValidSignature(sig));
262 this.arity = signatureArity(sig);
263 this.result = (signatureReturn(sig) == V_TYPE ? -1 : arity);
264 this.names = buildEmptyNames(arity, sig);
265 this.debugName = "LF.zero";
266 assert(nameRefsAreLegal());
267 assert(isEmpty());
268 assert(sig.equals(basicTypeSignature())) : sig + " != " + basicTypeSignature();
269 }
270
271 private static Name[] buildEmptyNames(int arity, String basicTypeSignature) {
272 assert(isValidSignature(basicTypeSignature));
273 int resultPos = arity + 1; // skip '_'
274 if (arity < 0 || basicTypeSignature.length() != resultPos+1)
275 throw new IllegalArgumentException("bad arity for "+basicTypeSignature);
276 int numRes = (basicType(basicTypeSignature.charAt(resultPos)) == V_TYPE ? 0 : 1);
277 Name[] names = arguments(numRes, basicTypeSignature.substring(0, arity));
278 for (int i = 0; i < numRes; i++) {
279 Name zero = new Name(constantZero(basicType(basicTypeSignature.charAt(resultPos + i))));
280 names[arity + i] = zero.newIndex(arity + i);
281 }
282 return names;
283 }
284
285 private static int fixResult(int result, Name[] names) {
286 if (result == LAST_RESULT)
287 result = names.length - 1; // might still be void
288 if (result >= 0 && names[result].type == V_TYPE)
289 result = -1;
290 return result;
291 }
292
293 private static String fixDebugName(String debugName) {
294 if (DEBUG_NAME_COUNTERS != null) {
295 int under = debugName.indexOf('_');
296 int length = debugName.length();
297 if (under < 0) under = length;
298 String debugNameStem = debugName.substring(0, under);
299 Integer ctr;
300 synchronized (DEBUG_NAME_COUNTERS) {
301 ctr = DEBUG_NAME_COUNTERS.get(debugNameStem);
302 if (ctr == null) ctr = 0;
303 DEBUG_NAME_COUNTERS.put(debugNameStem, ctr+1);
304 }
305 StringBuilder buf = new StringBuilder(debugNameStem);
306 buf.append('_');
307 int leadingZero = buf.length();
308 buf.append((int) ctr);
309 for (int i = buf.length() - leadingZero; i < 3; i++)
310 buf.insert(leadingZero, '0');
311 if (under < length) {
312 ++under; // skip "_"
313 while (under < length && Character.isDigit(debugName.charAt(under))) {
314 ++under;
315 }
316 if (under < length && debugName.charAt(under) == '_') ++under;
317 if (under < length)
318 buf.append('_').append(debugName, under, length);
319 }
320 return buf.toString();
321 }
322 return debugName;
323 }
324
325 private static boolean namesOK(int arity, Name[] names) {
326 for (int i = 0; i < names.length; i++) {
327 Name n = names[i];
328 assert(n != null) : "n is null";
329 if (i < arity)
330 assert( n.isParam()) : n + " is not param at " + i;
331 else
332 assert(!n.isParam()) : n + " is param at " + i;
333 }
334 return true;
335 }
336
337 /** Renumber and/or replace params so that they are interned and canonically numbered. */
338 private void normalize() {
339 Name[] oldNames = null;
340 int changesStart = 0;
341 for (int i = 0; i < names.length; i++) {
342 Name n = names[i];
343 if (!n.initIndex(i)) {
344 if (oldNames == null) {
345 oldNames = names.clone();
346 changesStart = i;
347 }
348 names[i] = n.cloneWithIndex(i);
349 }
350 }
351 if (oldNames != null) {
352 int startFixing = arity;
353 if (startFixing <= changesStart)
354 startFixing = changesStart+1;
355 for (int i = startFixing; i < names.length; i++) {
356 Name fixed = names[i].replaceNames(oldNames, names, changesStart, i);
357 names[i] = fixed.newIndex(i);
358 }
359 }
360 assert(nameRefsAreLegal());
361 int maxInterned = Math.min(arity, INTERNED_ARGUMENT_LIMIT);
362 boolean needIntern = false;
363 for (int i = 0; i < maxInterned; i++) {
364 Name n = names[i], n2 = internArgument(n);
365 if (n != n2) {
366 names[i] = n2;
367 needIntern = true;
368 }
369 }
370 if (needIntern) {
371 for (int i = arity; i < names.length; i++) {
372 names[i].internArguments();
373 }
374 assert(nameRefsAreLegal());
375 }
376 }
377
378 /**
379 * Check that all embedded Name references are localizable to this lambda,
380 * and are properly ordered after their corresponding definitions.
381 * <p>
382 * Note that a Name can be local to multiple lambdas, as long as
383 * it possesses the same index in each use site.
384 * This allows Name references to be freely reused to construct
385 * fresh lambdas, without confusion.
386 */
387 private boolean nameRefsAreLegal() {
388 assert(arity >= 0 && arity <= names.length);
389 assert(result >= -1 && result < names.length);
390 // Do all names possess an index consistent with their local definition order?
391 for (int i = 0; i < arity; i++) {
392 Name n = names[i];
393 assert(n.index() == i) : Arrays.asList(n.index(), i);
394 assert(n.isParam());
395 }
396 // Also, do all local name references
397 for (int i = arity; i < names.length; i++) {
398 Name n = names[i];
399 assert(n.index() == i);
400 for (Object arg : n.arguments) {
401 if (arg instanceof Name) {
402 Name n2 = (Name) arg;
403 int i2 = n2.index;
404 assert(0 <= i2 && i2 < names.length) : n.debugString() + ": 0 <= i2 && i2 < names.length: 0 <= " + i2 + " < " + names.length;
405 assert(names[i2] == n2) : Arrays.asList("-1-", i, "-2-", n.debugString(), "-3-", i2, "-4-", n2.debugString(), "-5-", names[i2].debugString(), "-6-", this);
406 assert(i2 < i); // ref must come after def!
407 }
408 }
409 }
410 return true;
411 }
412
413 /** Invoke this form on the given arguments. */
414 // final Object invoke(Object... args) throws Throwable {
415 // // NYI: fit this into the fast path?
416 // return interpretWithArguments(args);
417 // }
418
419 /** Report the return type. */
420 BasicType returnType() {
421 if (result < 0) return V_TYPE;
422 Name n = names[result];
423 return n.type;
424 }
425
426 /** Report the N-th argument type. */
427 BasicType parameterType(int n) {
428 assert(n < arity);
429 return names[n].type;
430 }
431
432 /** Report the arity. */
433 int arity() {
434 return arity;
435 }
436
437 /** Return the method type corresponding to my basic type signature. */
438 MethodType methodType() {
439 return signatureType(basicTypeSignature());
440 }
441 /** Return ABC_Z, where the ABC are parameter type characters, and Z is the return type character. */
442 final String basicTypeSignature() {
443 StringBuilder buf = new StringBuilder(arity() + 3);
444 for (int i = 0, a = arity(); i < a; i++)
445 buf.append(parameterType(i).basicTypeChar());
446 return buf.append('_').append(returnType().basicTypeChar()).toString();
447 }
448 static int signatureArity(String sig) {
449 assert(isValidSignature(sig));
450 return sig.indexOf('_');
451 }
452 static BasicType signatureReturn(String sig) {
453 return basicType(sig.charAt(signatureArity(sig)+1));
454 }
455 static boolean isValidSignature(String sig) {
456 int arity = sig.indexOf('_');
457 if (arity < 0) return false; // must be of the form *_*
458 int siglen = sig.length();
459 if (siglen != arity + 2) return false; // *_X
460 for (int i = 0; i < siglen; i++) {
461 if (i == arity) continue; // skip '_'
462 char c = sig.charAt(i);
463 if (c == 'V')
464 return (i == siglen - 1 && arity == siglen - 2);
465 if (!isArgBasicTypeChar(c)) return false; // must be [LIJFD]
466 }
467 return true; // [LIJFD]*_[LIJFDV]
468 }
469 static MethodType signatureType(String sig) {
470 Class<?>[] ptypes = new Class<?>[signatureArity(sig)];
471 for (int i = 0; i < ptypes.length; i++)
472 ptypes[i] = basicType(sig.charAt(i)).btClass;
473 Class<?> rtype = signatureReturn(sig).btClass;
474 return MethodType.methodType(rtype, ptypes);
475 }
476
477 /*
478 * Code generation issues:
479 *
480 * Compiled LFs should be reusable in general.
481 * The biggest issue is how to decide when to pull a name into
482 * the bytecode, versus loading a reified form from the MH data.
483 *
484 * For example, an asType wrapper may require execution of a cast
485 * after a call to a MH. The target type of the cast can be placed
486 * as a constant in the LF itself. This will force the cast type
487 * to be compiled into the bytecodes and native code for the MH.
488 * Or, the target type of the cast can be erased in the LF, and
489 * loaded from the MH data. (Later on, if the MH as a whole is
490 * inlined, the data will flow into the inlined instance of the LF,
491 * as a constant, and the end result will be an optimal cast.)
492 *
493 * This erasure of cast types can be done with any use of
494 * reference types. It can also be done with whole method
495 * handles. Erasing a method handle might leave behind
496 * LF code that executes correctly for any MH of a given
497 * type, and load the required MH from the enclosing MH's data.
498 * Or, the erasure might even erase the expected MT.
499 *
500 * Also, for direct MHs, the MemberName of the target
501 * could be erased, and loaded from the containing direct MH.
502 * As a simple case, a LF for all int-valued non-static
503 * field getters would perform a cast on its input argument
504 * (to non-constant base type derived from the MemberName)
505 * and load an integer value from the input object
506 * (at a non-constant offset also derived from the MemberName).
507 * Such MN-erased LFs would be inlinable back to optimized
508 * code, whenever a constant enclosing DMH is available
509 * to supply a constant MN from its data.
510 *
511 * The main problem here is to keep LFs reasonably generic,
512 * while ensuring that hot spots will inline good instances.
513 * "Reasonably generic" means that we don't end up with
514 * repeated versions of bytecode or machine code that do
515 * not differ in their optimized form. Repeated versions
516 * of machine would have the undesirable overheads of
517 * (a) redundant compilation work and (b) extra I$ pressure.
518 * To control repeated versions, we need to be ready to
519 * erase details from LFs and move them into MH data,
520 * whevener those details are not relevant to significant
521 * optimization. "Significant" means optimization of
522 * code that is actually hot.
523 *
524 * Achieving this may require dynamic splitting of MHs, by replacing
525 * a generic LF with a more specialized one, on the same MH,
526 * if (a) the MH is frequently executed and (b) the MH cannot
527 * be inlined into a containing caller, such as an invokedynamic.
528 *
529 * Compiled LFs that are no longer used should be GC-able.
530 * If they contain non-BCP references, they should be properly
531 * interlinked with the class loader(s) that their embedded types
532 * depend on. This probably means that reusable compiled LFs
533 * will be tabulated (indexed) on relevant class loaders,
534 * or else that the tables that cache them will have weak links.
535 */
536
537 /**
538 * Make this LF directly executable, as part of a MethodHandle.
539 * Invariant: Every MH which is invoked must prepare its LF
540 * before invocation.
541 * (In principle, the JVM could do this very lazily,
542 * as a sort of pre-invocation linkage step.)
543 */
544 public void prepare() {
545 if (COMPILE_THRESHOLD == 0) {
546 compileToBytecode();
547 }
548 if (this.vmentry != null) {
549 // already prepared (e.g., a primitive DMH invoker form)
550 return;
551 }
552 LambdaForm prep = getPreparedForm(basicTypeSignature());
553 this.vmentry = prep.vmentry;
554 // TO DO: Maybe add invokeGeneric, invokeWithArguments
555 }
556
557 /** Generate optimizable bytecode for this form. */
558 MemberName compileToBytecode() {
559 MethodType invokerType = methodType();
560 assert(vmentry == null || vmentry.getMethodType().basicType().equals(invokerType));
561 if (vmentry != null && isCompiled) {
562 return vmentry; // already compiled somehow
563 }
564 try {
565 vmentry = InvokerBytecodeGenerator.generateCustomizedCode(this, invokerType);
566 if (TRACE_INTERPRETER)
567 traceInterpreter("compileToBytecode", this);
568 isCompiled = true;
569 return vmentry;
570 } catch (Error | Exception ex) {
571 throw newInternalError("compileToBytecode", ex);
572 }
573 }
574
575 private static final ConcurrentHashMap<String,LambdaForm> PREPARED_FORMS;
576 static {
577 int capacity = 512; // expect many distinct signatures over time
578 float loadFactor = 0.75f; // normal default
579 int writers = 1;
580 PREPARED_FORMS = new ConcurrentHashMap<>(capacity, loadFactor, writers);
581 }
582
583 private static Map<String,LambdaForm> computeInitialPreparedForms() {
584 // Find all predefined invokers and associate them with canonical empty lambda forms.
585 HashMap<String,LambdaForm> forms = new HashMap<>();
586 for (MemberName m : MemberName.getFactory().getMethods(LambdaForm.class, false, null, null, null)) {
587 if (!m.isStatic() || !m.isPackage()) continue;
588 MethodType mt = m.getMethodType();
589 if (mt.parameterCount() > 0 &&
590 mt.parameterType(0) == MethodHandle.class &&
591 m.getName().startsWith("interpret_")) {
592 String sig = basicTypeSignature(mt);
593 assert(m.getName().equals("interpret" + sig.substring(sig.indexOf('_'))));
594 LambdaForm form = new LambdaForm(sig);
595 form.vmentry = m;
596 mt.form().setCachedLambdaForm(MethodTypeForm.LF_COUNTER, form);
597 // FIXME: get rid of PREPARED_FORMS; use MethodTypeForm cache only
598 forms.put(sig, form);
599 }
600 }
601 //System.out.println("computeInitialPreparedForms => "+forms);
602 return forms;
603 }
604
605 // Set this false to disable use of the interpret_L methods defined in this file.
606 private static final boolean USE_PREDEFINED_INTERPRET_METHODS = true;
607
608 // The following are predefined exact invokers. The system must build
609 // a separate invoker for each distinct signature.
610 static Object interpret_L(MethodHandle mh) throws Throwable {
611 Object[] av = {mh};
612 String sig = null;
613 assert(argumentTypesMatch(sig = "L_L", av));
614 Object res = mh.form.interpretWithArguments(av);
615 assert(returnTypesMatch(sig, av, res));
616 return res;
617 }
618 static Object interpret_L(MethodHandle mh, Object x1) throws Throwable {
619 Object[] av = {mh, x1};
620 String sig = null;
621 assert(argumentTypesMatch(sig = "LL_L", av));
622 Object res = mh.form.interpretWithArguments(av);
623 assert(returnTypesMatch(sig, av, res));
624 return res;
625 }
626 static Object interpret_L(MethodHandle mh, Object x1, Object x2) throws Throwable {
627 Object[] av = {mh, x1, x2};
628 String sig = null;
629 assert(argumentTypesMatch(sig = "LLL_L", av));
630 Object res = mh.form.interpretWithArguments(av);
631 assert(returnTypesMatch(sig, av, res));
632 return res;
633 }
634 private static LambdaForm getPreparedForm(String sig) {
635 MethodType mtype = signatureType(sig);
636 //LambdaForm prep = PREPARED_FORMS.get(sig);
637 LambdaForm prep = mtype.form().cachedLambdaForm(MethodTypeForm.LF_INTERPRET);
638 if (prep != null) return prep;
639 assert(isValidSignature(sig));
640 prep = new LambdaForm(sig);
641 prep.vmentry = InvokerBytecodeGenerator.generateLambdaFormInterpreterEntryPoint(sig);
642 //LambdaForm prep2 = PREPARED_FORMS.putIfAbsent(sig.intern(), prep);
643 return mtype.form().setCachedLambdaForm(MethodTypeForm.LF_INTERPRET, prep);
644 }
645
646 // The next few routines are called only from assert expressions
647 // They verify that the built-in invokers process the correct raw data types.
648 private static boolean argumentTypesMatch(String sig, Object[] av) {
649 int arity = signatureArity(sig);
650 assert(av.length == arity) : "av.length == arity: av.length=" + av.length + ", arity=" + arity;
651 assert(av[0] instanceof MethodHandle) : "av[0] not instace of MethodHandle: " + av[0];
652 MethodHandle mh = (MethodHandle) av[0];
653 MethodType mt = mh.type();
654 assert(mt.parameterCount() == arity-1);
655 for (int i = 0; i < av.length; i++) {
656 Class<?> pt = (i == 0 ? MethodHandle.class : mt.parameterType(i-1));
657 assert(valueMatches(basicType(sig.charAt(i)), pt, av[i]));
658 }
659 return true;
660 }
661 private static boolean valueMatches(BasicType tc, Class<?> type, Object x) {
662 // The following line is needed because (...)void method handles can use non-void invokers
663 if (type == void.class) tc = V_TYPE; // can drop any kind of value
664 assert tc == basicType(type) : tc + " == basicType(" + type + ")=" + basicType(type);
665 switch (tc) {
666 case I_TYPE: assert checkInt(type, x) : "checkInt(" + type + "," + x +")"; break;
667 case J_TYPE: assert x instanceof Long : "instanceof Long: " + x; break;
668 case F_TYPE: assert x instanceof Float : "instanceof Float: " + x; break;
669 case D_TYPE: assert x instanceof Double : "instanceof Double: " + x; break;
670 case L_TYPE: assert checkRef(type, x) : "checkRef(" + type + "," + x + ")"; break;
671 case V_TYPE: break; // allow anything here; will be dropped
672 default: assert(false);
673 }
674 return true;
675 }
676 private static boolean returnTypesMatch(String sig, Object[] av, Object res) {
677 MethodHandle mh = (MethodHandle) av[0];
678 return valueMatches(signatureReturn(sig), mh.type().returnType(), res);
679 }
680 private static boolean checkInt(Class<?> type, Object x) {
681 assert(x instanceof Integer);
682 if (type == int.class) return true;
683 Wrapper w = Wrapper.forBasicType(type);
684 assert(w.isSubwordOrInt());
685 Object x1 = Wrapper.INT.wrap(w.wrap(x));
686 return x.equals(x1);
687 }
688 private static boolean checkRef(Class<?> type, Object x) {
689 assert(!type.isPrimitive());
690 if (x == null) return true;
691 if (type.isInterface()) return true;
692 return type.isInstance(x);
693 }
694
695 /** If the invocation count hits the threshold we spin bytecodes and call that subsequently. */
696 private static final int COMPILE_THRESHOLD;
697 static {
698 if (MethodHandleStatics.COMPILE_THRESHOLD != null)
699 COMPILE_THRESHOLD = MethodHandleStatics.COMPILE_THRESHOLD;
700 else
701 COMPILE_THRESHOLD = 30; // default value
702 }
703 private int invocationCounter = 0;
704
705 @Hidden
706 @DontInline
707 /** Interpretively invoke this form on the given arguments. */
708 Object interpretWithArguments(Object... argumentValues) throws Throwable {
709 if (TRACE_INTERPRETER)
710 return interpretWithArgumentsTracing(argumentValues);
711 checkInvocationCounter();
712 assert(arityCheck(argumentValues));
713 Object[] values = Arrays.copyOf(argumentValues, names.length);
714 for (int i = argumentValues.length; i < values.length; i++) {
715 values[i] = interpretName(names[i], values);
716 }
717 return (result < 0) ? null : values[result];
718 }
719
720 @Hidden
721 @DontInline
722 /** Evaluate a single Name within this form, applying its function to its arguments. */
723 Object interpretName(Name name, Object[] values) throws Throwable {
724 if (TRACE_INTERPRETER)
725 traceInterpreter("| interpretName", name.debugString(), (Object[]) null);
726 Object[] arguments = Arrays.copyOf(name.arguments, name.arguments.length, Object[].class);
727 for (int i = 0; i < arguments.length; i++) {
728 Object a = arguments[i];
729 if (a instanceof Name) {
730 int i2 = ((Name)a).index();
731 assert(names[i2] == a);
732 a = values[i2];
733 arguments[i] = a;
734 }
735 }
736 return name.function.invokeWithArguments(arguments);
737 }
738
739 private void checkInvocationCounter() {
740 if (COMPILE_THRESHOLD != 0 &&
741 invocationCounter < COMPILE_THRESHOLD) {
742 invocationCounter++; // benign race
743 if (invocationCounter >= COMPILE_THRESHOLD) {
744 // Replace vmentry with a bytecode version of this LF.
745 compileToBytecode();
746 }
747 }
748 }
749 Object interpretWithArgumentsTracing(Object... argumentValues) throws Throwable {
750 traceInterpreter("[ interpretWithArguments", this, argumentValues);
751 if (invocationCounter < COMPILE_THRESHOLD) {
752 int ctr = invocationCounter++; // benign race
753 traceInterpreter("| invocationCounter", ctr);
754 if (invocationCounter >= COMPILE_THRESHOLD) {
755 compileToBytecode();
756 }
757 }
758 Object rval;
759 try {
760 assert(arityCheck(argumentValues));
761 Object[] values = Arrays.copyOf(argumentValues, names.length);
762 for (int i = argumentValues.length; i < values.length; i++) {
763 values[i] = interpretName(names[i], values);
764 }
765 rval = (result < 0) ? null : values[result];
766 } catch (Throwable ex) {
767 traceInterpreter("] throw =>", ex);
768 throw ex;
769 }
770 traceInterpreter("] return =>", rval);
771 return rval;
772 }
773
774 //** This transform is applied (statically) to every name.function. */
775 /*
776 private static MethodHandle eraseSubwordTypes(MethodHandle mh) {
777 MethodType mt = mh.type();
778 if (mt.hasPrimitives()) {
779 mt = mt.changeReturnType(eraseSubwordType(mt.returnType()));
780 for (int i = 0; i < mt.parameterCount(); i++) {
781 mt = mt.changeParameterType(i, eraseSubwordType(mt.parameterType(i)));
782 }
783 mh = MethodHandles.explicitCastArguments(mh, mt);
784 }
785 return mh;
786 }
787 private static Class<?> eraseSubwordType(Class<?> type) {
788 if (!type.isPrimitive()) return type;
789 if (type == int.class) return type;
790 Wrapper w = Wrapper.forPrimitiveType(type);
791 if (w.isSubwordOrInt()) return int.class;
792 return type;
793 }
794 */
795
796 static void traceInterpreter(String event, Object obj, Object... args) {
797 if (TRACE_INTERPRETER) {
798 System.out.println("LFI: "+event+" "+(obj != null ? obj : "")+(args != null && args.length != 0 ? Arrays.asList(args) : ""));
799 }
800 }
801 static void traceInterpreter(String event, Object obj) {
802 traceInterpreter(event, obj, (Object[])null);
803 }
804 private boolean arityCheck(Object[] argumentValues) {
805 assert(argumentValues.length == arity) : arity+"!="+Arrays.asList(argumentValues)+".length";
806 // also check that the leading (receiver) argument is somehow bound to this LF:
807 assert(argumentValues[0] instanceof MethodHandle) : "not MH: " + argumentValues[0];
808 assert(((MethodHandle)argumentValues[0]).internalForm() == this);
809 // note: argument #0 could also be an interface wrapper, in the future
810 return true;
811 }
812
813 private boolean isEmpty() {
814 if (result < 0)
815 return (names.length == arity);
816 else if (result == arity && names.length == arity + 1)
817 return names[arity].isConstantZero();
818 else
819 return false;
820 }
821
822 public String toString() {
823 StringBuilder buf = new StringBuilder(debugName+"=Lambda(");
824 for (int i = 0; i < names.length; i++) {
825 if (i == arity) buf.append(")=>{");
826 Name n = names[i];
827 if (i >= arity) buf.append("\n ");
828 buf.append(n);
829 if (i < arity) {
830 if (i+1 < arity) buf.append(",");
831 continue;
832 }
833 buf.append("=").append(n.exprString());
834 buf.append(";");
835 }
836 buf.append(result < 0 ? "void" : names[result]).append("}");
837 if (TRACE_INTERPRETER) {
838 // Extra verbosity:
839 buf.append(":").append(basicTypeSignature());
840 buf.append("/").append(vmentry);
841 }
842 return buf.toString();
843 }
844
845 /**
846 * Apply immediate binding for a Name in this form indicated by its position relative to the form.
847 * The first parameter to a LambdaForm, a0:L, always represents the form's method handle, so 0 is not
848 * accepted as valid.
849 */
850 LambdaForm bindImmediate(int pos, BasicType basicType, Object value) {
851 // must be an argument, and the types must match
852 assert pos > 0 && pos < arity && names[pos].type == basicType && Name.typesMatch(basicType, value);
853
854 int arity2 = arity - 1;
855 Name[] names2 = new Name[names.length - 1];
856 for (int r = 0, w = 0; r < names.length; ++r, ++w) { // (r)ead from names, (w)rite to names2
857 Name n = names[r];
858 if (n.isParam()) {
859 if (n.index == pos) {
860 // do not copy over the argument that is to be replaced with a literal,
861 // but adjust the write index
862 --w;
863 } else {
864 names2[w] = new Name(w, n.type);
865 }
866 } else {
867 Object[] arguments2 = new Object[n.arguments.length];
868 for (int i = 0; i < n.arguments.length; ++i) {
869 Object arg = n.arguments[i];
870 if (arg instanceof Name) {
871 int ni = ((Name) arg).index;
872 if (ni == pos) {
873 arguments2[i] = value;
874 } else if (ni < pos) {
875 // replacement position not yet passed
876 arguments2[i] = names2[ni];
877 } else {
878 // replacement position passed
879 arguments2[i] = names2[ni - 1];
880 }
881 } else {
882 arguments2[i] = arg;
883 }
884 }
885 names2[w] = new Name(n.function, arguments2);
886 names2[w].initIndex(w);
887 }
888 }
889
890 int result2 = result == -1 ? -1 : result - 1;
891 return new LambdaForm(debugName, arity2, names2, result2);
892 }
893
894 LambdaForm bind(int namePos, BoundMethodHandle.SpeciesData oldData) {
895 Name name = names[namePos];
896 BoundMethodHandle.SpeciesData newData = oldData.extendWith(name.type);
897 return bind(name, new Name(newData.getterFunction(oldData.fieldCount()), names[0]), oldData, newData);
898 }
899 LambdaForm bind(Name name, Name binding,
900 BoundMethodHandle.SpeciesData oldData,
901 BoundMethodHandle.SpeciesData newData) {
902 int pos = name.index;
903 assert(name.isParam());
904 assert(!binding.isParam());
905 assert(name.type == binding.type);
906 assert(0 <= pos && pos < arity && names[pos] == name);
907 assert(binding.function.memberDeclaringClassOrNull() == newData.clazz);
908 assert(oldData.getters.length == newData.getters.length-1);
909 if (bindCache != null) {
910 LambdaForm form = bindCache[pos];
911 if (form != null) {
912 assert(form.contains(binding)) : "form << " + form + " >> does not contain binding << " + binding + " >>";
913 return form;
914 }
915 } else {
916 bindCache = new LambdaForm[arity];
917 }
918 assert(nameRefsAreLegal());
919 int arity2 = arity-1;
920 Name[] names2 = names.clone();
921 names2[pos] = binding; // we might move this in a moment
922
923 // The newly created LF will run with a different BMH.
924 // Switch over any pre-existing BMH field references to the new BMH class.
925 int firstOldRef = -1;
926 for (int i = 0; i < names2.length; i++) {
927 Name n = names[i];
928 if (n.function != null &&
929 n.function.memberDeclaringClassOrNull() == oldData.clazz) {
930 MethodHandle oldGetter = n.function.resolvedHandle;
931 MethodHandle newGetter = null;
932 for (int j = 0; j < oldData.getters.length; j++) {
933 if (oldGetter == oldData.getters[j])
934 newGetter = newData.getters[j];
935 }
936 if (newGetter != null) {
937 if (firstOldRef < 0) firstOldRef = i;
938 Name n2 = new Name(newGetter, n.arguments);
939 names2[i] = n2;
940 }
941 }
942 }
943
944 // Walk over the new list of names once, in forward order.
945 // Replace references to 'name' with 'binding'.
946 // Replace data structure references to the old BMH species with the new.
947 // This might cause a ripple effect, but it will settle in one pass.
948 assert(firstOldRef < 0 || firstOldRef > pos);
949 for (int i = pos+1; i < names2.length; i++) {
950 if (i <= arity2) continue;
951 names2[i] = names2[i].replaceNames(names, names2, pos, i);
952 }
953
954 // (a0, a1, name=a2, a3, a4) => (a0, a1, a3, a4, binding)
955 int insPos = pos;
956 for (; insPos+1 < names2.length; insPos++) {
957 Name n = names2[insPos+1];
958 if (n.isSiblingBindingBefore(binding)) {
959 names2[insPos] = n;
960 } else {
961 break;
962 }
963 }
964 names2[insPos] = binding;
965
966 // Since we moved some stuff, maybe update the result reference:
967 int result2 = result;
968 if (result2 == pos)
969 result2 = insPos;
970 else if (result2 > pos && result2 <= insPos)
971 result2 -= 1;
972
973 return bindCache[pos] = new LambdaForm(debugName, arity2, names2, result2);
974 }
975
976 boolean contains(Name name) {
977 int pos = name.index();
978 if (pos >= 0) {
979 return pos < names.length && name.equals(names[pos]);
980 }
981 for (int i = arity; i < names.length; i++) {
982 if (name.equals(names[i]))
983 return true;
984 }
985 return false;
986 }
987
988 LambdaForm addArguments(int pos, BasicType... types) {
989 assert(pos <= arity);
990 int length = names.length;
991 int inTypes = types.length;
992 Name[] names2 = Arrays.copyOf(names, length + inTypes);
993 int arity2 = arity + inTypes;
994 int result2 = result;
995 if (result2 >= arity)
996 result2 += inTypes;
997 // names array has MH in slot 0; skip it.
998 int argpos = pos + 1;
999 // Note: The LF constructor will rename names2[argpos...].
1000 // Make space for new arguments (shift temporaries).
1001 System.arraycopy(names, argpos, names2, argpos + inTypes, length - argpos);
1002 for (int i = 0; i < inTypes; i++) {
1003 names2[argpos + i] = new Name(types[i]);
1004 }
1005 return new LambdaForm(debugName, arity2, names2, result2);
1006 }
1007
1008 LambdaForm addArguments(int pos, List<Class<?>> types) {
1009 BasicType[] basicTypes = new BasicType[types.size()];
1010 for (int i = 0; i < basicTypes.length; i++)
1011 basicTypes[i] = basicType(types.get(i));
1012 return addArguments(pos, basicTypes);
1013 }
1014
1015 LambdaForm permuteArguments(int skip, int[] reorder, BasicType[] types) {
1016 // Note: When inArg = reorder[outArg], outArg is fed by a copy of inArg.
1017 // The types are the types of the new (incoming) arguments.
1018 int length = names.length;
1019 int inTypes = types.length;
1020 int outArgs = reorder.length;
1021 assert(skip+outArgs == arity);
1022 assert(permutedTypesMatch(reorder, types, names, skip));
1023 int pos = 0;
1024 // skip trivial first part of reordering:
1025 while (pos < outArgs && reorder[pos] == pos) pos += 1;
1026 Name[] names2 = new Name[length - outArgs + inTypes];
1027 System.arraycopy(names, 0, names2, 0, skip+pos);
1028 // copy the body:
1029 int bodyLength = length - arity;
1030 System.arraycopy(names, skip+outArgs, names2, skip+inTypes, bodyLength);
1031 int arity2 = names2.length - bodyLength;
1032 int result2 = result;
1033 if (result2 >= 0) {
1034 if (result2 < skip+outArgs) {
1035 // return the corresponding inArg
1036 result2 = reorder[result2-skip];
1037 } else {
1038 result2 = result2 - outArgs + inTypes;
1039 }
1040 }
1041 // rework names in the body:
1042 for (int j = pos; j < outArgs; j++) {
1043 Name n = names[skip+j];
1044 int i = reorder[j];
1045 // replace names[skip+j] by names2[skip+i]
1046 Name n2 = names2[skip+i];
1047 if (n2 == null)
1048 names2[skip+i] = n2 = new Name(types[i]);
1049 else
1050 assert(n2.type == types[i]);
1051 for (int k = arity2; k < names2.length; k++) {
1052 names2[k] = names2[k].replaceName(n, n2);
1053 }
1054 }
1055 // some names are unused, but must be filled in
1056 for (int i = skip+pos; i < arity2; i++) {
1057 if (names2[i] == null)
1058 names2[i] = argument(i, types[i - skip]);
1059 }
1060 for (int j = arity; j < names.length; j++) {
1061 int i = j - arity + arity2;
1062 // replace names2[i] by names[j]
1063 Name n = names[j];
1064 Name n2 = names2[i];
1065 if (n != n2) {
1066 for (int k = i+1; k < names2.length; k++) {
1067 names2[k] = names2[k].replaceName(n, n2);
1068 }
1069 }
1070 }
1071 return new LambdaForm(debugName, arity2, names2, result2);
1072 }
1073
1074 static boolean permutedTypesMatch(int[] reorder, BasicType[] types, Name[] names, int skip) {
1075 int inTypes = types.length;
1076 int outArgs = reorder.length;
1077 for (int i = 0; i < outArgs; i++) {
1078 assert(names[skip+i].isParam());
1079 assert(names[skip+i].type == types[reorder[i]]);
1080 }
1081 return true;
1082 }
1083
1084 static class NamedFunction {
1085 final MemberName member;
1086 @Stable MethodHandle resolvedHandle;
1087 @Stable MethodHandle invoker;
1088
1089 NamedFunction(MethodHandle resolvedHandle) {
1090 this(resolvedHandle.internalMemberName(), resolvedHandle);
1091 }
1092 NamedFunction(MemberName member, MethodHandle resolvedHandle) {
1093 this.member = member;
1094 //resolvedHandle = eraseSubwordTypes(resolvedHandle);
1095 this.resolvedHandle = resolvedHandle;
1096 }
1097 NamedFunction(MethodType basicInvokerType) {
1098 assert(basicInvokerType == basicInvokerType.basicType()) : basicInvokerType;
1099 if (basicInvokerType.parameterSlotCount() < MethodType.MAX_MH_INVOKER_ARITY) {
1100 this.resolvedHandle = basicInvokerType.invokers().basicInvoker();
1101 this.member = resolvedHandle.internalMemberName();
1102 } else {
1103 // necessary to pass BigArityTest
1104 this.member = Invokers.invokeBasicMethod(basicInvokerType);
1105 }
1106 }
1107
1108 // The next 3 constructors are used to break circular dependencies on MH.invokeStatic, etc.
1109 // Any LambdaForm containing such a member is not interpretable.
1110 // This is OK, since all such LFs are prepared with special primitive vmentry points.
1111 // And even without the resolvedHandle, the name can still be compiled and optimized.
1112 NamedFunction(Method method) {
1113 this(new MemberName(method));
1114 }
1115 NamedFunction(Field field) {
1116 this(new MemberName(field));
1117 }
1118 NamedFunction(MemberName member) {
1119 this.member = member;
1120 this.resolvedHandle = null;
1121 }
1122
1123 MethodHandle resolvedHandle() {
1124 if (resolvedHandle == null) resolve();
1125 return resolvedHandle;
1126 }
1127
1128 void resolve() {
1129 resolvedHandle = DirectMethodHandle.make(member);
1130 }
1131
1132 @Override
1133 public boolean equals(Object other) {
1134 if (this == other) return true;
1135 if (other == null) return false;
1136 if (!(other instanceof NamedFunction)) return false;
1137 NamedFunction that = (NamedFunction) other;
1138 return this.member != null && this.member.equals(that.member);
1139 }
1140
1141 @Override
1142 public int hashCode() {
1143 if (member != null)
1144 return member.hashCode();
1145 return super.hashCode();
1146 }
1147
1148 // Put the predefined NamedFunction invokers into the table.
1149 static void initializeInvokers() {
1150 for (MemberName m : MemberName.getFactory().getMethods(NamedFunction.class, false, null, null, null)) {
1151 if (!m.isStatic() || !m.isPackage()) continue;
1152 MethodType type = m.getMethodType();
1153 if (type.equals(INVOKER_METHOD_TYPE) &&
1154 m.getName().startsWith("invoke_")) {
1155 String sig = m.getName().substring("invoke_".length());
1156 int arity = LambdaForm.signatureArity(sig);
1157 MethodType srcType = MethodType.genericMethodType(arity);
1158 if (LambdaForm.signatureReturn(sig) == V_TYPE)
1159 srcType = srcType.changeReturnType(void.class);
1160 MethodTypeForm typeForm = srcType.form();
1161 typeForm.namedFunctionInvoker = DirectMethodHandle.make(m);
1162 }
1163 }
1164 }
1165
1166 // The following are predefined NamedFunction invokers. The system must build
1167 // a separate invoker for each distinct signature.
1168 /** void return type invokers. */
1169 @Hidden
1170 static Object invoke__V(MethodHandle mh, Object[] a) throws Throwable {
1171 assert(a.length == 0);
1172 mh.invokeBasic();
1173 return null;
1174 }
1175 @Hidden
1176 static Object invoke_L_V(MethodHandle mh, Object[] a) throws Throwable {
1177 assert(a.length == 1);
1178 mh.invokeBasic(a[0]);
1179 return null;
1180 }
1181 @Hidden
1182 static Object invoke_LL_V(MethodHandle mh, Object[] a) throws Throwable {
1183 assert(a.length == 2);
1184 mh.invokeBasic(a[0], a[1]);
1185 return null;
1186 }
1187 @Hidden
1188 static Object invoke_LLL_V(MethodHandle mh, Object[] a) throws Throwable {
1189 assert(a.length == 3);
1190 mh.invokeBasic(a[0], a[1], a[2]);
1191 return null;
1192 }
1193 @Hidden
1194 static Object invoke_LLLL_V(MethodHandle mh, Object[] a) throws Throwable {
1195 assert(a.length == 4);
1196 mh.invokeBasic(a[0], a[1], a[2], a[3]);
1197 return null;
1198 }
1199 @Hidden
1200 static Object invoke_LLLLL_V(MethodHandle mh, Object[] a) throws Throwable {
1201 assert(a.length == 5);
1202 mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]);
1203 return null;
1204 }
1205 /** Object return type invokers. */
1206 @Hidden
1207 static Object invoke__L(MethodHandle mh, Object[] a) throws Throwable {
1208 assert(a.length == 0);
1209 return mh.invokeBasic();
1210 }
1211 @Hidden
1212 static Object invoke_L_L(MethodHandle mh, Object[] a) throws Throwable {
1213 assert(a.length == 1);
1214 return mh.invokeBasic(a[0]);
1215 }
1216 @Hidden
1217 static Object invoke_LL_L(MethodHandle mh, Object[] a) throws Throwable {
1218 assert(a.length == 2);
1219 return mh.invokeBasic(a[0], a[1]);
1220 }
1221 @Hidden
1222 static Object invoke_LLL_L(MethodHandle mh, Object[] a) throws Throwable {
1223 assert(a.length == 3);
1224 return mh.invokeBasic(a[0], a[1], a[2]);
1225 }
1226 @Hidden
1227 static Object invoke_LLLL_L(MethodHandle mh, Object[] a) throws Throwable {
1228 assert(a.length == 4);
1229 return mh.invokeBasic(a[0], a[1], a[2], a[3]);
1230 }
1231 @Hidden
1232 static Object invoke_LLLLL_L(MethodHandle mh, Object[] a) throws Throwable {
1233 assert(a.length == 5);
1234 return mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]);
1235 }
1236
1237 static final MethodType INVOKER_METHOD_TYPE =
1238 MethodType.methodType(Object.class, MethodHandle.class, Object[].class);
1239
1240 private static MethodHandle computeInvoker(MethodTypeForm typeForm) {
1241 MethodHandle mh = typeForm.namedFunctionInvoker;
1242 if (mh != null) return mh;
1243 MemberName invoker = InvokerBytecodeGenerator.generateNamedFunctionInvoker(typeForm); // this could take a while
1244 mh = DirectMethodHandle.make(invoker);
1245 MethodHandle mh2 = typeForm.namedFunctionInvoker;
1246 if (mh2 != null) return mh2; // benign race
1247 if (!mh.type().equals(INVOKER_METHOD_TYPE))
1248 throw newInternalError(mh.debugString());
1249 return typeForm.namedFunctionInvoker = mh;
1250 }
1251
1252 @Hidden
1253 Object invokeWithArguments(Object... arguments) throws Throwable {
1254 // If we have a cached invoker, call it right away.
1255 // NOTE: The invoker always returns a reference value.
1256 if (TRACE_INTERPRETER) return invokeWithArgumentsTracing(arguments);
1257 assert(checkArgumentTypes(arguments, methodType()));
1258 return invoker().invokeBasic(resolvedHandle(), arguments);
1259 }
1260
1261 @Hidden
1262 Object invokeWithArgumentsTracing(Object[] arguments) throws Throwable {
1263 Object rval;
1264 try {
1265 traceInterpreter("[ call", this, arguments);
1266 if (invoker == null) {
1267 traceInterpreter("| getInvoker", this);
1268 invoker();
1269 }
1270 if (resolvedHandle == null) {
1271 traceInterpreter("| resolve", this);
1272 resolvedHandle();
1273 }
1274 assert(checkArgumentTypes(arguments, methodType()));
1275 rval = invoker().invokeBasic(resolvedHandle(), arguments);
1276 } catch (Throwable ex) {
1277 traceInterpreter("] throw =>", ex);
1278 throw ex;
1279 }
1280 traceInterpreter("] return =>", rval);
1281 return rval;
1282 }
1283
1284 private MethodHandle invoker() {
1285 if (invoker != null) return invoker;
1286 // Get an invoker and cache it.
1287 return invoker = computeInvoker(methodType().form());
1288 }
1289
1290 private static boolean checkArgumentTypes(Object[] arguments, MethodType methodType) {
1291 if (true) return true; // FIXME
1292 MethodType dstType = methodType.form().erasedType();
1293 MethodType srcType = dstType.basicType().wrap();
1294 Class<?>[] ptypes = new Class<?>[arguments.length];
1295 for (int i = 0; i < arguments.length; i++) {
1296 Object arg = arguments[i];
1297 Class<?> ptype = arg == null ? Object.class : arg.getClass();
1298 // If the dest. type is a primitive we keep the
1299 // argument type.
1300 ptypes[i] = dstType.parameterType(i).isPrimitive() ? ptype : Object.class;
1301 }
1302 MethodType argType = MethodType.methodType(srcType.returnType(), ptypes).wrap();
1303 assert(argType.isConvertibleTo(srcType)) : "wrong argument types: cannot convert " + argType + " to " + srcType;
1304 return true;
1305 }
1306
1307 String basicTypeSignature() {
1308 //return LambdaForm.basicTypeSignature(resolvedHandle.type());
1309 return LambdaForm.basicTypeSignature(methodType());
1310 }
1311
1312 MethodType methodType() {
1313 if (resolvedHandle != null)
1314 return resolvedHandle.type();
1315 else
1316 // only for certain internal LFs during bootstrapping
1317 return member.getInvocationType();
1318 }
1319
1320 MemberName member() {
1321 assert(assertMemberIsConsistent());
1322 return member;
1323 }
1324
1325 // Called only from assert.
1326 private boolean assertMemberIsConsistent() {
1327 if (resolvedHandle instanceof DirectMethodHandle) {
1328 MemberName m = resolvedHandle.internalMemberName();
1329 assert(m.equals(member));
1330 }
1331 return true;
1332 }
1333
1334 Class<?> memberDeclaringClassOrNull() {
1335 return (member == null) ? null : member.getDeclaringClass();
1336 }
1337
1338 BasicType returnType() {
1339 return basicType(methodType().returnType());
1340 }
1341
1342 BasicType parameterType(int n) {
1343 return basicType(methodType().parameterType(n));
1344 }
1345
1346 int arity() {
1347 //int siglen = member.getMethodType().parameterCount();
1348 //if (!member.isStatic()) siglen += 1;
1349 //return siglen;
1350 return methodType().parameterCount();
1351 }
1352
1353 public String toString() {
1354 if (member == null) return String.valueOf(resolvedHandle);
1355 return member.getDeclaringClass().getSimpleName()+"."+member.getName();
1356 }
1357
1358 public boolean isIdentity() {
1359 return this.equals(identity(returnType()));
1360 }
1361
1362 public boolean isConstantZero() {
1363 return this.equals(constantZero(returnType()));
1364 }
1365 }
1366
1367 void resolve() {
1368 for (Name n : names) n.resolve();
1369 }
1370
1371 public static String basicTypeSignature(MethodType type) {
1372 char[] sig = new char[type.parameterCount() + 2];
1373 int sigp = 0;
1374 for (Class<?> pt : type.parameterList()) {
1375 sig[sigp++] = basicTypeChar(pt);
1376 }
1377 sig[sigp++] = '_';
1378 sig[sigp++] = basicTypeChar(type.returnType());
1379 assert(sigp == sig.length);
1380 return String.valueOf(sig);
1381 }
1382 public static String shortenSignature(String signature) {
1383 // Hack to make signatures more readable when they show up in method names.
1384 final int NO_CHAR = -1, MIN_RUN = 3;
1385 int c0, c1 = NO_CHAR, c1reps = 0;
1386 StringBuilder buf = null;
1387 int len = signature.length();
1388 if (len < MIN_RUN) return signature;
1389 for (int i = 0; i <= len; i++) {
1390 // shift in the next char:
1391 c0 = c1; c1 = (i == len ? NO_CHAR : signature.charAt(i));
1392 if (c1 == c0) { ++c1reps; continue; }
1393 // shift in the next count:
1394 int c0reps = c1reps; c1reps = 1;
1395 // end of a character run
1396 if (c0reps < MIN_RUN) {
1397 if (buf != null) {
1398 while (--c0reps >= 0)
1399 buf.append((char)c0);
1400 }
1401 continue;
1402 }
1403 // found three or more in a row
1404 if (buf == null)
1405 buf = new StringBuilder().append(signature, 0, i - c0reps);
1406 buf.append((char)c0).append(c0reps);
1407 }
1408 return (buf == null) ? signature : buf.toString();
1409 }
1410 static void testShortenSignature() {
1411 for (String s : new String[] {
1412 // invariant strings:
1413 "L", "LL", "ILL", "LIL", "LLI", "IILL", "ILIL", "ILLI",
1414 // a few mappings:
1415 "LLL=L3", "LLLL=L4", "LLLLLLLLLL=L10",
1416 "IIIDDD=I3D3", "IDDD=ID3", "IIDDD=IID3", "IIID=I3D", "IIIDD=I3DD"
1417 }) {
1418 String s2 = s.substring(s.indexOf('=')+1);
1419 String s1 = s.equals(s2) ? s : s.substring(0, s.length() - s2.length() - 1);
1420 // mix the above cases with before and after reps of Z*
1421 for (int k = -3; k <= 3; k++) {
1422 String beg = (k < 0 ? "ZZZZ".substring(-k) : "");
1423 String end = (k > 0 ? "ZZZZ".substring(+k) : "");
1424 String ks1 = beg+s1+end;
1425 String ks2 = shortenSignature(beg)+s2+shortenSignature(end);
1426 String ks3 = shortenSignature(ks1);
1427 if (!ks3.equals(ks2)) System.out.println(Arrays.asList(ks1, ks2, ks3));
1428 assert(ks3.equals(ks2)) : Arrays.asList(ks1, ks2, ks3);
1429 }
1430 }
1431 }
1432
1433 static final class Name {
1434 final BasicType type;
1435 private short index;
1436 final NamedFunction function;
1437 @Stable final Object[] arguments;
1438
1439 private Name(int index, BasicType type, NamedFunction function, Object[] arguments) {
1440 this.index = (short)index;
1441 this.type = type;
1442 this.function = function;
1443 this.arguments = arguments;
1444 assert(this.index == index);
1445 }
1446 Name(MethodHandle function, Object... arguments) {
1447 this(new NamedFunction(function), arguments);
1448 }
1449 Name(MethodType functionType, Object... arguments) {
1450 this(new NamedFunction(functionType), arguments);
1451 assert(arguments[0] instanceof Name && ((Name)arguments[0]).type == L_TYPE);
1452 }
1453 Name(MemberName function, Object... arguments) {
1454 this(new NamedFunction(function), arguments);
1455 }
1456 Name(NamedFunction function, Object... arguments) {
1457 this(-1, function.returnType(), function, arguments = arguments.clone());
1458 assert(arguments.length == function.arity()) : "arity mismatch: arguments.length=" + arguments.length + " == function.arity()=" + function.arity() + " in " + debugString();
1459 for (int i = 0; i < arguments.length; i++)
1460 assert(typesMatch(function.parameterType(i), arguments[i])) : "types don't match: function.parameterType(" + i + ")=" + function.parameterType(i) + ", arguments[" + i + "]=" + arguments[i] + " in " + debugString();
1461 }
1462 /** Create a raw parameter of the given type, with an expected index. */
1463 Name(int index, BasicType type) {
1464 this(index, type, null, null);
1465 }
1466 /** Create a raw parameter of the given type. */
1467 Name(BasicType type) { this(-1, type); }
1468
1469 BasicType type() { return type; }
1470 int index() { return index; }
1471 boolean initIndex(int i) {
1472 if (index != i) {
1473 if (index != -1) return false;
1474 index = (short)i;
1475 }
1476 return true;
1477 }
1478 char typeChar() {
1479 return type.btChar;
1480 }
1481
1482 void resolve() {
1483 if (function != null)
1484 function.resolve();
1485 }
1486
1487 Name newIndex(int i) {
1488 if (initIndex(i)) return this;
1489 return cloneWithIndex(i);
1490 }
1491 Name cloneWithIndex(int i) {
1492 Object[] newArguments = (arguments == null) ? null : arguments.clone();
1493 return new Name(i, type, function, newArguments);
1494 }
1495 Name replaceName(Name oldName, Name newName) { // FIXME: use replaceNames uniformly
1496 if (oldName == newName) return this;
1497 @SuppressWarnings("LocalVariableHidesMemberVariable")
1498 Object[] arguments = this.arguments;
1499 if (arguments == null) return this;
1500 boolean replaced = false;
1501 for (int j = 0; j < arguments.length; j++) {
1502 if (arguments[j] == oldName) {
1503 if (!replaced) {
1504 replaced = true;
1505 arguments = arguments.clone();
1506 }
1507 arguments[j] = newName;
1508 }
1509 }
1510 if (!replaced) return this;
1511 return new Name(function, arguments);
1512 }
1513 Name replaceNames(Name[] oldNames, Name[] newNames, int start, int end) {
1514 @SuppressWarnings("LocalVariableHidesMemberVariable")
1515 Object[] arguments = this.arguments;
1516 boolean replaced = false;
1517 eachArg:
1518 for (int j = 0; j < arguments.length; j++) {
1519 if (arguments[j] instanceof Name) {
1520 Name n = (Name) arguments[j];
1521 int check = n.index;
1522 // harmless check to see if the thing is already in newNames:
1523 if (check >= 0 && check < newNames.length && n == newNames[check])
1524 continue eachArg;
1525 // n might not have the correct index: n != oldNames[n.index].
1526 for (int i = start; i < end; i++) {
1527 if (n == oldNames[i]) {
1528 if (n == newNames[i])
1529 continue eachArg;
1530 if (!replaced) {
1531 replaced = true;
1532 arguments = arguments.clone();
1533 }
1534 arguments[j] = newNames[i];
1535 continue eachArg;
1536 }
1537 }
1538 }
1539 }
1540 if (!replaced) return this;
1541 return new Name(function, arguments);
1542 }
1543 void internArguments() {
1544 @SuppressWarnings("LocalVariableHidesMemberVariable")
1545 Object[] arguments = this.arguments;
1546 for (int j = 0; j < arguments.length; j++) {
1547 if (arguments[j] instanceof Name) {
1548 Name n = (Name) arguments[j];
1549 if (n.isParam() && n.index < INTERNED_ARGUMENT_LIMIT)
1550 arguments[j] = internArgument(n);
1551 }
1552 }
1553 }
1554 boolean isParam() {
1555 return function == null;
1556 }
1557 boolean isConstantZero() {
1558 return !isParam() && arguments.length == 0 && function.isConstantZero();
1559 }
1560
1561 public String toString() {
1562 return (isParam()?"a":"t")+(index >= 0 ? index : System.identityHashCode(this))+":"+typeChar();
1563 }
1564 public String debugString() {
1565 String s = toString();
1566 return (function == null) ? s : s + "=" + exprString();
1567 }
1568 public String exprString() {
1569 if (function == null) return toString();
1570 StringBuilder buf = new StringBuilder(function.toString());
1571 buf.append("(");
1572 String cma = "";
1573 for (Object a : arguments) {
1574 buf.append(cma); cma = ",";
1575 if (a instanceof Name || a instanceof Integer)
1576 buf.append(a);
1577 else
1578 buf.append("(").append(a).append(")");
1579 }
1580 buf.append(")");
1581 return buf.toString();
1582 }
1583
1584 static boolean typesMatch(BasicType parameterType, Object object) {
1585 if (object instanceof Name) {
1586 return ((Name)object).type == parameterType;
1587 }
1588 switch (parameterType) {
1589 case I_TYPE: return object instanceof Integer;
1590 case J_TYPE: return object instanceof Long;
1591 case F_TYPE: return object instanceof Float;
1592 case D_TYPE: return object instanceof Double;
1593 }
1594 assert(parameterType == L_TYPE);
1595 return true;
1596 }
1597
1598 /**
1599 * Does this Name precede the given binding node in some canonical order?
1600 * This predicate is used to order data bindings (via insertion sort)
1601 * with some stability.
1602 */
1603 boolean isSiblingBindingBefore(Name binding) {
1604 assert(!binding.isParam());
1605 if (isParam()) return true;
1606 if (function.equals(binding.function) &&
1607 arguments.length == binding.arguments.length) {
1608 boolean sawInt = false;
1609 for (int i = 0; i < arguments.length; i++) {
1610 Object a1 = arguments[i];
1611 Object a2 = binding.arguments[i];
1612 if (!a1.equals(a2)) {
1613 if (a1 instanceof Integer && a2 instanceof Integer) {
1614 if (sawInt) continue;
1615 sawInt = true;
1616 if ((int)a1 < (int)a2) continue; // still might be true
1617 }
1618 return false;
1619 }
1620 }
1621 return sawInt;
1622 }
1623 return false;
1624 }
1625
1626 /** Return the index of the last occurrence of n in the argument array.
1627 * Return -1 if the name is not used.
1628 */
1629 int lastUseIndex(Name n) {
1630 if (arguments == null) return -1;
1631 for (int i = arguments.length; --i >= 0; ) {
1632 if (arguments[i] == n) return i;
1633 }
1634 return -1;
1635 }
1636
1637 /** Return the number of occurrences of n in the argument array.
1638 * Return 0 if the name is not used.
1639 */
1640 int useCount(Name n) {
1641 if (arguments == null) return 0;
1642 int count = 0;
1643 for (int i = arguments.length; --i >= 0; ) {
1644 if (arguments[i] == n) ++count;
1645 }
1646 return count;
1647 }
1648
1649 boolean contains(Name n) {
1650 return this == n || lastUseIndex(n) >= 0;
1651 }
1652
1653 public boolean equals(Name that) {
1654 if (this == that) return true;
1655 if (isParam())
1656 // each parameter is a unique atom
1657 return false; // this != that
1658 return
1659 //this.index == that.index &&
1660 this.type == that.type &&
1661 this.function.equals(that.function) &&
1662 Arrays.equals(this.arguments, that.arguments);
1663 }
1664 @Override
1665 public boolean equals(Object x) {
1666 return x instanceof Name && equals((Name)x);
1667 }
1668 @Override
1669 public int hashCode() {
1670 if (isParam())
1671 return index | (type.ordinal() << 8);
1672 return function.hashCode() ^ Arrays.hashCode(arguments);
1673 }
1674 }
1675
1676 /** Return the index of the last name which contains n as an argument.
1677 * Return -1 if the name is not used. Return names.length if it is the return value.
1678 */
1679 int lastUseIndex(Name n) {
1680 int ni = n.index, nmax = names.length;
1681 assert(names[ni] == n);
1682 if (result == ni) return nmax; // live all the way beyond the end
1683 for (int i = nmax; --i > ni; ) {
1684 if (names[i].lastUseIndex(n) >= 0)
1685 return i;
1686 }
1687 return -1;
1688 }
1689
1690 /** Return the number of times n is used as an argument or return value. */
1691 int useCount(Name n) {
1692 int ni = n.index, nmax = names.length;
1693 int end = lastUseIndex(n);
1694 if (end < 0) return 0;
1695 int count = 0;
1696 if (end == nmax) { count++; end--; }
1697 int beg = n.index() + 1;
1698 if (beg < arity) beg = arity;
1699 for (int i = beg; i <= end; i++) {
1700 count += names[i].useCount(n);
1701 }
1702 return count;
1703 }
1704
1705 static Name argument(int which, char type) {
1706 return argument(which, basicType(type));
1707 }
1708 static Name argument(int which, BasicType type) {
1709 if (which >= INTERNED_ARGUMENT_LIMIT)
1710 return new Name(which, type);
1711 return INTERNED_ARGUMENTS[type.ordinal()][which];
1712 }
1713 static Name internArgument(Name n) {
1714 assert(n.isParam()) : "not param: " + n;
1715 assert(n.index < INTERNED_ARGUMENT_LIMIT);
1716 return argument(n.index, n.type);
1717 }
1718 static Name[] arguments(int extra, String types) {
1719 int length = types.length();
1720 Name[] names = new Name[length + extra];
1721 for (int i = 0; i < length; i++)
1722 names[i] = argument(i, types.charAt(i));
1723 return names;
1724 }
1725 static Name[] arguments(int extra, char... types) {
1726 int length = types.length;
1727 Name[] names = new Name[length + extra];
1728 for (int i = 0; i < length; i++)
1729 names[i] = argument(i, types[i]);
1730 return names;
1731 }
1732 static Name[] arguments(int extra, List<Class<?>> types) {
1733 int length = types.size();
1734 Name[] names = new Name[length + extra];
1735 for (int i = 0; i < length; i++)
1736 names[i] = argument(i, basicType(types.get(i)));
1737 return names;
1738 }
1739 static Name[] arguments(int extra, Class<?>... types) {
1740 int length = types.length;
1741 Name[] names = new Name[length + extra];
1742 for (int i = 0; i < length; i++)
1743 names[i] = argument(i, basicType(types[i]));
1744 return names;
1745 }
1746 static Name[] arguments(int extra, MethodType types) {
1747 int length = types.parameterCount();
1748 Name[] names = new Name[length + extra];
1749 for (int i = 0; i < length; i++)
1750 names[i] = argument(i, basicType(types.parameterType(i)));
1751 return names;
1752 }
1753 static final int INTERNED_ARGUMENT_LIMIT = 10;
1754 private static final Name[][] INTERNED_ARGUMENTS
1755 = new Name[ARG_TYPE_LIMIT][INTERNED_ARGUMENT_LIMIT];
1756 static {
1757 for (BasicType type : BasicType.ARG_TYPES) {
1758 int id = type.ordinal();
1759 for (int i = 0; i < INTERNED_ARGUMENTS[id].length; i++) {
1760 INTERNED_ARGUMENTS[id][i] = new Name(i, type);
1761 }
1762 }
1763 }
1764
1765 private static final MemberName.Factory IMPL_NAMES = MemberName.getFactory();
1766
1767 static LambdaForm identityForm(BasicType type) {
1768 return LF_identityForm[type.ordinal()];
1769 }
1770 static LambdaForm zeroForm(BasicType type) {
1771 return LF_zeroForm[type.ordinal()];
1772 }
1773 static NamedFunction identity(BasicType type) {
1774 return NF_identity[type.ordinal()];
1775 }
1776 static NamedFunction constantZero(BasicType type) {
1777 return NF_zero[type.ordinal()];
1778 }
1779 private static final LambdaForm[] LF_identityForm = new LambdaForm[TYPE_LIMIT];
1780 private static final LambdaForm[] LF_zeroForm = new LambdaForm[TYPE_LIMIT];
1781 private static final NamedFunction[] NF_identity = new NamedFunction[TYPE_LIMIT];
1782 private static final NamedFunction[] NF_zero = new NamedFunction[TYPE_LIMIT];
1783 private static void createIdentityForms() {
1784 for (BasicType type : BasicType.ALL_TYPES) {
1785 int btId = type.ordinal();
1786 char btChar = type.basicTypeChar();
1787 boolean isVoid = (type == V_TYPE);
1788 Class<?> btClass = type.btClass;
1789 MethodType zeType = MethodType.methodType(btClass);
1790 MethodType idType = isVoid ? zeType : zeType.appendParameterTypes(btClass);
1791
1792 // Look up some symbolic names. It might not be necessary to have these,
1793 // but if we need to emit direct references to bytecodes, it helps.
1794 // Zero is built from a call to an identity function with a constant zero input.
1795 MemberName idMem = new MemberName(LambdaForm.class, "identity_"+btChar, idType, REF_invokeStatic);
1796 MemberName zeMem = new MemberName(LambdaForm.class, "zero_"+btChar, zeType, REF_invokeStatic);
1797 try {
1798 zeMem = IMPL_NAMES.resolveOrFail(REF_invokeStatic, zeMem, null, NoSuchMethodException.class);
1799 idMem = IMPL_NAMES.resolveOrFail(REF_invokeStatic, idMem, null, NoSuchMethodException.class);
1800 } catch (IllegalAccessException|NoSuchMethodException ex) {
1801 throw newInternalError(ex);
1802 }
1803
1804 NamedFunction idFun = new NamedFunction(idMem);
1805 LambdaForm idForm;
1806 if (isVoid) {
1807 Name[] idNames = new Name[] { argument(0, L_TYPE) };
1808 idForm = new LambdaForm(idMem.getName(), 1, idNames, VOID_RESULT);
1809 } else {
1810 Name[] idNames = new Name[] { argument(0, L_TYPE), argument(1, type) };
1811 idForm = new LambdaForm(idMem.getName(), 2, idNames, 1);
1812 }
1813 LF_identityForm[btId] = idForm;
1814 NF_identity[btId] = idFun;
1815 //idFun.resolvedHandle = SimpleMethodHandle.make(idMem.getInvocationType(), idForm);
1816
1817 NamedFunction zeFun = new NamedFunction(zeMem);
1818 LambdaForm zeForm;
1819 if (isVoid) {
1820 zeForm = idForm;
1821 } else {
1822 Object zeValue = Wrapper.forBasicType(btChar).zero();
1823 Name[] zeNames = new Name[] { argument(0, L_TYPE), new Name(idFun, zeValue) };
1824 zeForm = new LambdaForm(zeMem.getName(), 1, zeNames, 1);
1825 }
1826 LF_zeroForm[btId] = zeForm;
1827 NF_zero[btId] = zeFun;
1828 //zeFun.resolvedHandle = SimpleMethodHandle.make(zeMem.getInvocationType(), zeForm);
1829
1830 assert(idFun.isIdentity());
1831 assert(zeFun.isConstantZero());
1832 assert(new Name(zeFun).isConstantZero());
1833 }
1834
1835 // Do this in a separate pass, so that SimpleMethodHandle.make can see the tables.
1836 for (BasicType type : BasicType.ALL_TYPES) {
1837 int btId = type.ordinal();
1838 NamedFunction idFun = NF_identity[btId];
1839 LambdaForm idForm = LF_identityForm[btId];
1840 MemberName idMem = idFun.member;
1841 idFun.resolvedHandle = SimpleMethodHandle.make(idMem.getInvocationType(), idForm);
1842
1843 NamedFunction zeFun = NF_zero[btId];
1844 LambdaForm zeForm = LF_zeroForm[btId];
1845 MemberName zeMem = zeFun.member;
1846 zeFun.resolvedHandle = SimpleMethodHandle.make(zeMem.getInvocationType(), zeForm);
1847
1848 assert(idFun.isIdentity());
1849 assert(zeFun.isConstantZero());
1850 assert(new Name(zeFun).isConstantZero());
1851 }
1852 }
1853
1854 // Avoid appealing to ValueConversions at bootstrap time:
1855 private static int identity_I(int x) { return x; }
1856 private static long identity_J(long x) { return x; }
1857 private static float identity_F(float x) { return x; }
1858 private static double identity_D(double x) { return x; }
1859 private static Object identity_L(Object x) { return x; }
1860 private static void identity_V() { return; } // same as zeroV, but that's OK
1861 private static int zero_I() { return 0; }
1862 private static long zero_J() { return 0; }
1863 private static float zero_F() { return 0; }
1864 private static double zero_D() { return 0; }
1865 private static Object zero_L() { return null; }
1866 private static void zero_V() { return; }
1867
1868 /**
1869 * Internal marker for byte-compiled LambdaForms.
1870 */
1871 /*non-public*/
1872 @Target(ElementType.METHOD)
1873 @Retention(RetentionPolicy.RUNTIME)
1874 @interface Compiled {
1875 }
1876
1877 /**
1878 * Internal marker for LambdaForm interpreter frames.
1879 */
1880 /*non-public*/
1881 @Target(ElementType.METHOD)
1882 @Retention(RetentionPolicy.RUNTIME)
1883 @interface Hidden {
1884 }
1885
1886
1887 /*
1888 // Smoke-test for the invokers used in this file.
1889 static void testMethodHandleLinkers() throws Throwable {
1890 MemberName.Factory lookup = MemberName.getFactory();
1891 MemberName asList_MN = new MemberName(Arrays.class, "asList",
1892 MethodType.methodType(List.class, Object[].class),
1893 REF_invokeStatic);
1894 //MethodHandleNatives.resolve(asList_MN, null);
1895 asList_MN = lookup.resolveOrFail(asList_MN, REF_invokeStatic, null, NoSuchMethodException.class);
1896 System.out.println("about to call "+asList_MN);
1897 Object[] abc = { "a", "bc" };
1898 List<?> lst = (List<?>) MethodHandle.linkToStatic(abc, asList_MN);
1899 System.out.println("lst="+lst);
1900 MemberName toString_MN = new MemberName(Object.class.getMethod("toString"));
1901 String s1 = (String) MethodHandle.linkToVirtual(lst, toString_MN);
1902 toString_MN = new MemberName(Object.class.getMethod("toString"), true);
1903 String s2 = (String) MethodHandle.linkToSpecial(lst, toString_MN);
1904 System.out.println("[s1,s2,lst]="+Arrays.asList(s1, s2, lst.toString()));
1905 MemberName toArray_MN = new MemberName(List.class.getMethod("toArray"));
1906 Object[] arr = (Object[]) MethodHandle.linkToInterface(lst, toArray_MN);
1907 System.out.println("toArray="+Arrays.toString(arr));
1908 }
1909 static { try { testMethodHandleLinkers(); } catch (Throwable ex) { throw new RuntimeException(ex); } }
1910 // Requires these definitions in MethodHandle:
1911 static final native Object linkToStatic(Object x1, MemberName mn) throws Throwable;
1912 static final native Object linkToVirtual(Object x1, MemberName mn) throws Throwable;
1913 static final native Object linkToSpecial(Object x1, MemberName mn) throws Throwable;
1914 static final native Object linkToInterface(Object x1, MemberName mn) throws Throwable;
1915 */
1916
1917 private static final HashMap<String,Integer> DEBUG_NAME_COUNTERS;
1918 static {
1919 if (debugEnabled())
1920 DEBUG_NAME_COUNTERS = new HashMap<>();
1921 else
1922 DEBUG_NAME_COUNTERS = null;
1923 }
1924
1925 // Put this last, so that previous static inits can run before.
1926 static {
1927 createIdentityForms();
1928 if (USE_PREDEFINED_INTERPRET_METHODS)
1929 PREPARED_FORMS.putAll(computeInitialPreparedForms());
1930 NamedFunction.initializeInvokers();
1931 }
1932
1933 // The following hack is necessary in order to suppress TRACE_INTERPRETER
1934 // during execution of the static initializes of this class.
1935 // Turning on TRACE_INTERPRETER too early will cause
1936 // stack overflows and other misbehavior during attempts to trace events
1937 // that occur during LambdaForm.<clinit>.
1938 // Therefore, do not move this line higher in this file, and do not remove.
1939 private static final boolean TRACE_INTERPRETER = MethodHandleStatics.TRACE_INTERPRETER;
1940 }