1 /*
2 * Copyright (c) 2011, 2014, 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.List;
31 import java.util.Arrays;
32 import java.util.HashMap;
33
34 import sun.invoke.util.Wrapper;
35 import java.lang.reflect.Field;
36
37 import static java.lang.invoke.LambdaForm.BasicType.*;
38 import static java.lang.invoke.MethodHandleStatics.*;
39 import static java.lang.invoke.MethodHandleNatives.Constants.*;
40
41 /**
42 * The symbolic, non-executable form of a method handle's invocation semantics.
43 * It consists of a series of names.
44 * The first N (N=arity) names are parameters,
45 * while any remaining names are temporary values.
46 * Each temporary specifies the application of a function to some arguments.
47 * The functions are method handles, while the arguments are mixes of
48 * constant values and local names.
49 * The result of the lambda is defined as one of the names, often the last one.
50 * <p>
51 * Here is an approximate grammar:
52 * <blockquote><pre>{@code
53 * LambdaForm = "(" ArgName* ")=>{" TempName* Result "}"
54 * ArgName = "a" N ":" T
55 * TempName = "t" N ":" T "=" Function "(" Argument* ");"
56 * Function = ConstantValue
57 * Argument = NameRef | ConstantValue
58 * Result = NameRef | "void"
59 * NameRef = "a" N | "t" N
60 * N = (any whole number)
61 * T = "L" | "I" | "J" | "F" | "D" | "V"
62 * }</pre></blockquote>
63 * Names are numbered consecutively from left to right starting at zero.
64 * (The letters are merely a taste of syntax sugar.)
65 * Thus, the first temporary (if any) is always numbered N (where N=arity).
66 * Every occurrence of a name reference in an argument list must refer to
67 * a name previously defined within the same lambda.
68 * A lambda has a void result if and only if its result index is -1.
69 * If a temporary has the type "V", it cannot be the subject of a NameRef,
70 * even though possesses a number.
71 * Note that all reference types are erased to "L", which stands for {@code Object}.
72 * All subword types (boolean, byte, short, char) are erased to "I" which is {@code int}.
73 * The other types stand for the usual primitive types.
74 * <p>
75 * Function invocation closely follows the static rules of the Java verifier.
76 * Arguments and return values must exactly match when their "Name" types are
77 * considered.
78 * Conversions are allowed only if they do not change the erased type.
79 * <ul>
80 * <li>L = Object: casts are used freely to convert into and out of reference types
81 * <li>I = int: subword types are forcibly narrowed when passed as arguments (see {@code explicitCastArguments})
82 * <li>J = long: no implicit conversions
83 * <li>F = float: no implicit conversions
84 * <li>D = double: no implicit conversions
85 * <li>V = void: a function result may be void if and only if its Name is of type "V"
86 * </ul>
87 * Although implicit conversions are not allowed, explicit ones can easily be
88 * encoded by using temporary expressions which call type-transformed identity functions.
89 * <p>
90 * Examples:
91 * <blockquote><pre>{@code
92 * (a0:J)=>{ a0 }
93 * == identity(long)
94 * (a0:I)=>{ t1:V = System.out#println(a0); void }
95 * == System.out#println(int)
96 * (a0:L)=>{ t1:V = System.out#println(a0); a0 }
97 * == identity, with printing side-effect
98 * (a0:L, a1:L)=>{ t2:L = BoundMethodHandle#argument(a0);
99 * t3:L = BoundMethodHandle#target(a0);
100 * t4:L = MethodHandle#invoke(t3, t2, a1); t4 }
101 * == general invoker for unary insertArgument combination
102 * (a0:L, a1:L)=>{ t2:L = FilterMethodHandle#filter(a0);
103 * t3:L = MethodHandle#invoke(t2, a1);
104 * t4:L = FilterMethodHandle#target(a0);
105 * t5:L = MethodHandle#invoke(t4, t3); t5 }
106 * == general invoker for unary filterArgument combination
107 * (a0:L, a1:L)=>{ ...(same as previous example)...
108 * t5:L = MethodHandle#invoke(t4, t3, a1); t5 }
109 * == general invoker for unary/unary foldArgument combination
110 * (a0:L, a1:I)=>{ t2:I = identity(long).asType((int)->long)(a1); t2 }
111 * == invoker for identity method handle which performs i2l
112 * (a0:L, a1:L)=>{ t2:L = BoundMethodHandle#argument(a0);
113 * t3:L = Class#cast(t2,a1); t3 }
114 * == invoker for identity method handle which performs cast
115 * }</pre></blockquote>
116 * <p>
117 * @author John Rose, JSR 292 EG
118 */
119 class LambdaForm {
120 final int arity;
121 final int result;
122 final boolean forceInline;
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 Object transformCache; // managed by LambdaFormEditor
129
130 public static final int VOID_RESULT = -1, LAST_RESULT = -2;
131
132 enum BasicType {
133 L_TYPE('L', Object.class, Wrapper.OBJECT), // all reference types
134 I_TYPE('I', int.class, Wrapper.INT),
135 J_TYPE('J', long.class, Wrapper.LONG),
136 F_TYPE('F', float.class, Wrapper.FLOAT),
137 D_TYPE('D', double.class, Wrapper.DOUBLE), // all primitive types
138 V_TYPE('V', void.class, Wrapper.VOID); // not valid in all contexts
139
140 static final BasicType[] ALL_TYPES = BasicType.values();
141 static final BasicType[] ARG_TYPES = Arrays.copyOf(ALL_TYPES, ALL_TYPES.length-1);
142
143 static final int ARG_TYPE_LIMIT = ARG_TYPES.length;
144 static final int TYPE_LIMIT = ALL_TYPES.length;
145
146 private final char btChar;
147 private final Class<?> btClass;
148 private final Wrapper btWrapper;
149
150 private BasicType(char btChar, Class<?> btClass, Wrapper wrapper) {
151 this.btChar = btChar;
152 this.btClass = btClass;
153 this.btWrapper = wrapper;
154 }
155
156 char basicTypeChar() {
157 return btChar;
158 }
159 Class<?> basicTypeClass() {
160 return btClass;
161 }
162 Wrapper basicTypeWrapper() {
163 return btWrapper;
164 }
165 int basicTypeSlots() {
166 return btWrapper.stackSlots();
167 }
168
169 static BasicType basicType(byte type) {
170 return ALL_TYPES[type];
171 }
172 static BasicType basicType(char type) {
173 switch (type) {
174 case 'L': return L_TYPE;
175 case 'I': return I_TYPE;
176 case 'J': return J_TYPE;
177 case 'F': return F_TYPE;
178 case 'D': return D_TYPE;
179 case 'V': return V_TYPE;
180 // all subword types are represented as ints
181 case 'Z':
182 case 'B':
183 case 'S':
184 case 'C':
185 return I_TYPE;
186 default:
187 throw newInternalError("Unknown type char: '"+type+"'");
188 }
189 }
190 static BasicType basicType(Wrapper type) {
191 char c = type.basicTypeChar();
192 return basicType(c);
193 }
194 static BasicType basicType(Class<?> type) {
195 if (!type.isPrimitive()) return L_TYPE;
196 return basicType(Wrapper.forPrimitiveType(type));
197 }
198
199 static char basicTypeChar(Class<?> type) {
200 return basicType(type).btChar;
201 }
202 static BasicType[] basicTypes(List<Class<?>> types) {
203 BasicType[] btypes = new BasicType[types.size()];
204 for (int i = 0; i < btypes.length; i++) {
205 btypes[i] = basicType(types.get(i));
206 }
207 return btypes;
208 }
209 static BasicType[] basicTypes(String types) {
210 BasicType[] btypes = new BasicType[types.length()];
211 for (int i = 0; i < btypes.length; i++) {
212 btypes[i] = basicType(types.charAt(i));
213 }
214 return btypes;
215 }
216 static byte[] basicTypesOrd(BasicType[] btypes) {
217 byte[] ords = new byte[btypes.length];
218 for (int i = 0; i < btypes.length; i++) {
219 ords[i] = (byte)btypes[i].ordinal();
220 }
221 return ords;
222 }
223 static boolean isBasicTypeChar(char c) {
224 return "LIJFDV".indexOf(c) >= 0;
225 }
226 static boolean isArgBasicTypeChar(char c) {
227 return "LIJFD".indexOf(c) >= 0;
228 }
229
230 static { assert(checkBasicType()); }
231 private static boolean checkBasicType() {
232 for (int i = 0; i < ARG_TYPE_LIMIT; i++) {
233 assert ARG_TYPES[i].ordinal() == i;
234 assert ARG_TYPES[i] == ALL_TYPES[i];
235 }
236 for (int i = 0; i < TYPE_LIMIT; i++) {
237 assert ALL_TYPES[i].ordinal() == i;
238 }
239 assert ALL_TYPES[TYPE_LIMIT - 1] == V_TYPE;
240 assert !Arrays.asList(ARG_TYPES).contains(V_TYPE);
241 return true;
242 }
243 }
244
245 LambdaForm(String debugName,
246 int arity, Name[] names, int result) {
247 this(debugName, arity, names, result, true);
248 }
249 LambdaForm(String debugName,
250 int arity, Name[] names, int result, boolean forceInline) {
251 assert(namesOK(arity, names));
252 this.arity = arity;
253 this.result = fixResult(result, names);
254 this.names = names.clone();
255 this.debugName = fixDebugName(debugName);
256 this.forceInline = forceInline;
257 int maxOutArity = normalize();
258 if (maxOutArity > MethodType.MAX_MH_INVOKER_ARITY) {
259 // Cannot use LF interpreter on very high arity expressions.
260 assert(maxOutArity <= MethodType.MAX_JVM_ARITY);
261 compileToBytecode();
262 }
263 }
264 LambdaForm(String debugName,
265 int arity, Name[] names) {
266 this(debugName, arity, names, LAST_RESULT, true);
267 }
268 LambdaForm(String debugName,
269 int arity, Name[] names, boolean forceInline) {
270 this(debugName, arity, names, LAST_RESULT, forceInline);
271 }
272 LambdaForm(String debugName,
273 Name[] formals, Name[] temps, Name result) {
274 this(debugName,
275 formals.length, buildNames(formals, temps, result), LAST_RESULT, true);
276 }
277 LambdaForm(String debugName,
278 Name[] formals, Name[] temps, Name result, boolean forceInline) {
279 this(debugName,
280 formals.length, buildNames(formals, temps, result), LAST_RESULT, forceInline);
281 }
282
283 private static Name[] buildNames(Name[] formals, Name[] temps, Name result) {
284 int arity = formals.length;
285 int length = arity + temps.length + (result == null ? 0 : 1);
286 Name[] names = Arrays.copyOf(formals, length);
287 System.arraycopy(temps, 0, names, arity, temps.length);
288 if (result != null)
289 names[length - 1] = result;
290 return names;
291 }
292
293 private LambdaForm(String sig) {
294 this(sig, true);
295 }
296
297 private LambdaForm(String sig, boolean forceInline) {
298 // Make a blank lambda form, which returns a constant zero or null.
299 // It is used as a template for managing the invocation of similar forms that are non-empty.
300 // Called only from getPreparedForm.
301 assert(isValidSignature(sig));
302 this.arity = signatureArity(sig);
303 this.result = (signatureReturn(sig) == V_TYPE ? -1 : arity);
304 this.names = buildEmptyNames(arity, sig);
305 this.debugName = "LF.zero";
306 this.forceInline = forceInline;
307 assert(nameRefsAreLegal());
308 assert(isEmpty());
309 assert(sig.equals(basicTypeSignature())) : sig + " != " + basicTypeSignature();
310 }
311
312 private static Name[] buildEmptyNames(int arity, String basicTypeSignature) {
313 assert(isValidSignature(basicTypeSignature));
314 int resultPos = arity + 1; // skip '_'
315 if (arity < 0 || basicTypeSignature.length() != resultPos+1)
316 throw new IllegalArgumentException("bad arity for "+basicTypeSignature);
317 int numRes = (basicType(basicTypeSignature.charAt(resultPos)) == V_TYPE ? 0 : 1);
318 Name[] names = arguments(numRes, basicTypeSignature.substring(0, arity));
319 for (int i = 0; i < numRes; i++) {
320 Name zero = new Name(constantZero(basicType(basicTypeSignature.charAt(resultPos + i))));
321 names[arity + i] = zero.newIndex(arity + i);
322 }
323 return names;
324 }
325
326 private static int fixResult(int result, Name[] names) {
327 if (result == LAST_RESULT)
328 result = names.length - 1; // might still be void
329 if (result >= 0 && names[result].type == V_TYPE)
330 result = VOID_RESULT;
331 return result;
332 }
333
334 private static String fixDebugName(String debugName) {
335 if (DEBUG_NAME_COUNTERS != null) {
336 int under = debugName.indexOf('_');
337 int length = debugName.length();
338 if (under < 0) under = length;
339 String debugNameStem = debugName.substring(0, under);
340 Integer ctr;
341 synchronized (DEBUG_NAME_COUNTERS) {
342 ctr = DEBUG_NAME_COUNTERS.get(debugNameStem);
343 if (ctr == null) ctr = 0;
344 DEBUG_NAME_COUNTERS.put(debugNameStem, ctr+1);
345 }
346 StringBuilder buf = new StringBuilder(debugNameStem);
347 buf.append('_');
348 int leadingZero = buf.length();
349 buf.append((int) ctr);
350 for (int i = buf.length() - leadingZero; i < 3; i++)
351 buf.insert(leadingZero, '0');
352 if (under < length) {
353 ++under; // skip "_"
354 while (under < length && Character.isDigit(debugName.charAt(under))) {
355 ++under;
356 }
357 if (under < length && debugName.charAt(under) == '_') ++under;
358 if (under < length)
359 buf.append('_').append(debugName, under, length);
360 }
361 return buf.toString();
362 }
363 return debugName;
364 }
365
366 private static boolean namesOK(int arity, Name[] names) {
367 for (int i = 0; i < names.length; i++) {
368 Name n = names[i];
369 assert(n != null) : "n is null";
370 if (i < arity)
371 assert( n.isParam()) : n + " is not param at " + i;
372 else
373 assert(!n.isParam()) : n + " is param at " + i;
374 }
375 return true;
376 }
377
378 /** Renumber and/or replace params so that they are interned and canonically numbered.
379 * @return maximum argument list length among the names (since we have to pass over them anyway)
380 */
381 private int normalize() {
382 Name[] oldNames = null;
383 int maxOutArity = 0;
384 int changesStart = 0;
385 for (int i = 0; i < names.length; i++) {
386 Name n = names[i];
387 if (!n.initIndex(i)) {
388 if (oldNames == null) {
389 oldNames = names.clone();
390 changesStart = i;
391 }
392 names[i] = n.cloneWithIndex(i);
393 }
394 if (n.arguments != null && maxOutArity < n.arguments.length)
395 maxOutArity = n.arguments.length;
396 }
397 if (oldNames != null) {
398 int startFixing = arity;
399 if (startFixing <= changesStart)
400 startFixing = changesStart+1;
401 for (int i = startFixing; i < names.length; i++) {
402 Name fixed = names[i].replaceNames(oldNames, names, changesStart, i);
403 names[i] = fixed.newIndex(i);
404 }
405 }
406 assert(nameRefsAreLegal());
407 int maxInterned = Math.min(arity, INTERNED_ARGUMENT_LIMIT);
408 boolean needIntern = false;
409 for (int i = 0; i < maxInterned; i++) {
410 Name n = names[i], n2 = internArgument(n);
411 if (n != n2) {
412 names[i] = n2;
413 needIntern = true;
414 }
415 }
416 if (needIntern) {
417 for (int i = arity; i < names.length; i++) {
418 names[i].internArguments();
419 }
420 assert(nameRefsAreLegal());
421 }
422 return maxOutArity;
423 }
424
425 /**
426 * Check that all embedded Name references are localizable to this lambda,
427 * and are properly ordered after their corresponding definitions.
428 * <p>
429 * Note that a Name can be local to multiple lambdas, as long as
430 * it possesses the same index in each use site.
431 * This allows Name references to be freely reused to construct
432 * fresh lambdas, without confusion.
433 */
434 boolean nameRefsAreLegal() {
435 assert(arity >= 0 && arity <= names.length);
436 assert(result >= -1 && result < names.length);
437 // Do all names possess an index consistent with their local definition order?
438 for (int i = 0; i < arity; i++) {
439 Name n = names[i];
440 assert(n.index() == i) : Arrays.asList(n.index(), i);
441 assert(n.isParam());
442 }
443 // Also, do all local name references
444 for (int i = arity; i < names.length; i++) {
445 Name n = names[i];
446 assert(n.index() == i);
447 for (Object arg : n.arguments) {
448 if (arg instanceof Name) {
449 Name n2 = (Name) arg;
450 int i2 = n2.index;
451 assert(0 <= i2 && i2 < names.length) : n.debugString() + ": 0 <= i2 && i2 < names.length: 0 <= " + i2 + " < " + names.length;
452 assert(names[i2] == n2) : Arrays.asList("-1-", i, "-2-", n.debugString(), "-3-", i2, "-4-", n2.debugString(), "-5-", names[i2].debugString(), "-6-", this);
453 assert(i2 < i); // ref must come after def!
454 }
455 }
456 }
457 return true;
458 }
459
460 /** Invoke this form on the given arguments. */
461 // final Object invoke(Object... args) throws Throwable {
462 // // NYI: fit this into the fast path?
463 // return interpretWithArguments(args);
464 // }
465
466 /** Report the return type. */
467 BasicType returnType() {
468 if (result < 0) return V_TYPE;
469 Name n = names[result];
470 return n.type;
471 }
472
473 /** Report the N-th argument type. */
474 BasicType parameterType(int n) {
475 return parameter(n).type;
476 }
477
478 /** Report the N-th argument name. */
479 Name parameter(int n) {
480 assert(n < arity);
481 Name param = names[n];
482 assert(param.isParam());
483 return param;
484 }
485
486 /** Report the N-th argument type constraint. */
487 Object parameterConstraint(int n) {
488 return parameter(n).constraint;
489 }
490
491 /** Report the arity. */
492 int arity() {
493 return arity;
494 }
495
496 /** Report the number of expressions (non-parameter names). */
497 int expressionCount() {
498 return names.length - arity;
499 }
500
501 /** Return the method type corresponding to my basic type signature. */
502 MethodType methodType() {
503 return signatureType(basicTypeSignature());
504 }
505 /** Return ABC_Z, where the ABC are parameter type characters, and Z is the return type character. */
506 final String basicTypeSignature() {
507 StringBuilder buf = new StringBuilder(arity() + 3);
508 for (int i = 0, a = arity(); i < a; i++)
509 buf.append(parameterType(i).basicTypeChar());
510 return buf.append('_').append(returnType().basicTypeChar()).toString();
511 }
512 static int signatureArity(String sig) {
513 assert(isValidSignature(sig));
514 return sig.indexOf('_');
515 }
516 static BasicType signatureReturn(String sig) {
517 return basicType(sig.charAt(signatureArity(sig) + 1));
518 }
519 static boolean isValidSignature(String sig) {
520 int arity = sig.indexOf('_');
521 if (arity < 0) return false; // must be of the form *_*
522 int siglen = sig.length();
523 if (siglen != arity + 2) return false; // *_X
524 for (int i = 0; i < siglen; i++) {
525 if (i == arity) continue; // skip '_'
526 char c = sig.charAt(i);
527 if (c == 'V')
528 return (i == siglen - 1 && arity == siglen - 2);
529 if (!isArgBasicTypeChar(c)) return false; // must be [LIJFD]
530 }
531 return true; // [LIJFD]*_[LIJFDV]
532 }
533 static MethodType signatureType(String sig) {
534 Class<?>[] ptypes = new Class<?>[signatureArity(sig)];
535 for (int i = 0; i < ptypes.length; i++)
536 ptypes[i] = basicType(sig.charAt(i)).btClass;
537 Class<?> rtype = signatureReturn(sig).btClass;
538 return MethodType.methodType(rtype, ptypes);
539 }
540
541 /*
542 * Code generation issues:
543 *
544 * Compiled LFs should be reusable in general.
545 * The biggest issue is how to decide when to pull a name into
546 * the bytecode, versus loading a reified form from the MH data.
547 *
548 * For example, an asType wrapper may require execution of a cast
549 * after a call to a MH. The target type of the cast can be placed
550 * as a constant in the LF itself. This will force the cast type
551 * to be compiled into the bytecodes and native code for the MH.
552 * Or, the target type of the cast can be erased in the LF, and
553 * loaded from the MH data. (Later on, if the MH as a whole is
554 * inlined, the data will flow into the inlined instance of the LF,
555 * as a constant, and the end result will be an optimal cast.)
556 *
557 * This erasure of cast types can be done with any use of
558 * reference types. It can also be done with whole method
559 * handles. Erasing a method handle might leave behind
560 * LF code that executes correctly for any MH of a given
561 * type, and load the required MH from the enclosing MH's data.
562 * Or, the erasure might even erase the expected MT.
563 *
564 * Also, for direct MHs, the MemberName of the target
565 * could be erased, and loaded from the containing direct MH.
566 * As a simple case, a LF for all int-valued non-static
567 * field getters would perform a cast on its input argument
568 * (to non-constant base type derived from the MemberName)
569 * and load an integer value from the input object
570 * (at a non-constant offset also derived from the MemberName).
571 * Such MN-erased LFs would be inlinable back to optimized
572 * code, whenever a constant enclosing DMH is available
573 * to supply a constant MN from its data.
574 *
575 * The main problem here is to keep LFs reasonably generic,
576 * while ensuring that hot spots will inline good instances.
577 * "Reasonably generic" means that we don't end up with
578 * repeated versions of bytecode or machine code that do
579 * not differ in their optimized form. Repeated versions
580 * of machine would have the undesirable overheads of
581 * (a) redundant compilation work and (b) extra I$ pressure.
582 * To control repeated versions, we need to be ready to
583 * erase details from LFs and move them into MH data,
584 * whevener those details are not relevant to significant
585 * optimization. "Significant" means optimization of
586 * code that is actually hot.
587 *
588 * Achieving this may require dynamic splitting of MHs, by replacing
589 * a generic LF with a more specialized one, on the same MH,
590 * if (a) the MH is frequently executed and (b) the MH cannot
591 * be inlined into a containing caller, such as an invokedynamic.
592 *
593 * Compiled LFs that are no longer used should be GC-able.
594 * If they contain non-BCP references, they should be properly
595 * interlinked with the class loader(s) that their embedded types
596 * depend on. This probably means that reusable compiled LFs
597 * will be tabulated (indexed) on relevant class loaders,
598 * or else that the tables that cache them will have weak links.
599 */
600
601 /**
602 * Make this LF directly executable, as part of a MethodHandle.
603 * Invariant: Every MH which is invoked must prepare its LF
604 * before invocation.
605 * (In principle, the JVM could do this very lazily,
606 * as a sort of pre-invocation linkage step.)
607 */
608 public void prepare() {
609 if (COMPILE_THRESHOLD == 0) {
610 compileToBytecode();
611 }
612 if (this.vmentry != null) {
613 // already prepared (e.g., a primitive DMH invoker form)
614 return;
615 }
616 LambdaForm prep = getPreparedForm(basicTypeSignature());
617 this.vmentry = prep.vmentry;
618 // TO DO: Maybe add invokeGeneric, invokeWithArguments
619 }
620
621 /** Generate optimizable bytecode for this form. */
622 MemberName compileToBytecode() {
623 MethodType invokerType = methodType();
624 assert(vmentry == null || vmentry.getMethodType().basicType().equals(invokerType));
625 if (vmentry != null && isCompiled) {
626 return vmentry; // already compiled somehow
627 }
628 try {
629 vmentry = InvokerBytecodeGenerator.generateCustomizedCode(this, invokerType);
630 if (TRACE_INTERPRETER)
631 traceInterpreter("compileToBytecode", this);
632 isCompiled = true;
633 return vmentry;
634 } catch (Error | Exception ex) {
635 throw newInternalError(this.toString(), ex);
636 }
637 }
638
639 private static void computeInitialPreparedForms() {
640 // Find all predefined invokers and associate them with canonical empty lambda forms.
641 for (MemberName m : MemberName.getFactory().getMethods(LambdaForm.class, false, null, null, null)) {
642 if (!m.isStatic() || !m.isPackage()) continue;
643 MethodType mt = m.getMethodType();
644 if (mt.parameterCount() > 0 &&
645 mt.parameterType(0) == MethodHandle.class &&
646 m.getName().startsWith("interpret_")) {
647 String sig = basicTypeSignature(mt);
648 assert(m.getName().equals("interpret" + sig.substring(sig.indexOf('_'))));
649 LambdaForm form = new LambdaForm(sig);
650 form.vmentry = m;
651 form = mt.form().setCachedLambdaForm(MethodTypeForm.LF_INTERPRET, form);
652 }
653 }
654 }
655
656 // Set this false to disable use of the interpret_L methods defined in this file.
657 private static final boolean USE_PREDEFINED_INTERPRET_METHODS = true;
658
659 // The following are predefined exact invokers. The system must build
660 // a separate invoker for each distinct signature.
661 static Object interpret_L(MethodHandle mh) throws Throwable {
662 Object[] av = {mh};
663 String sig = null;
664 assert(argumentTypesMatch(sig = "L_L", av));
665 Object res = mh.form.interpretWithArguments(av);
666 assert(returnTypesMatch(sig, av, res));
667 return res;
668 }
669 static Object interpret_L(MethodHandle mh, Object x1) throws Throwable {
670 Object[] av = {mh, x1};
671 String sig = null;
672 assert(argumentTypesMatch(sig = "LL_L", av));
673 Object res = mh.form.interpretWithArguments(av);
674 assert(returnTypesMatch(sig, av, res));
675 return res;
676 }
677 static Object interpret_L(MethodHandle mh, Object x1, Object x2) throws Throwable {
678 Object[] av = {mh, x1, x2};
679 String sig = null;
680 assert(argumentTypesMatch(sig = "LLL_L", av));
681 Object res = mh.form.interpretWithArguments(av);
682 assert(returnTypesMatch(sig, av, res));
683 return res;
684 }
685 private static LambdaForm getPreparedForm(String sig) {
686 MethodType mtype = signatureType(sig);
687 LambdaForm prep = mtype.form().cachedLambdaForm(MethodTypeForm.LF_INTERPRET);
688 if (prep != null) return prep;
689 assert(isValidSignature(sig));
690 prep = new LambdaForm(sig);
691 prep.vmentry = InvokerBytecodeGenerator.generateLambdaFormInterpreterEntryPoint(sig);
692 return mtype.form().setCachedLambdaForm(MethodTypeForm.LF_INTERPRET, prep);
693 }
694
695 // The next few routines are called only from assert expressions
696 // They verify that the built-in invokers process the correct raw data types.
697 private static boolean argumentTypesMatch(String sig, Object[] av) {
698 int arity = signatureArity(sig);
699 assert(av.length == arity) : "av.length == arity: av.length=" + av.length + ", arity=" + arity;
700 assert(av[0] instanceof MethodHandle) : "av[0] not instace of MethodHandle: " + av[0];
701 MethodHandle mh = (MethodHandle) av[0];
702 MethodType mt = mh.type();
703 assert(mt.parameterCount() == arity-1);
704 for (int i = 0; i < av.length; i++) {
705 Class<?> pt = (i == 0 ? MethodHandle.class : mt.parameterType(i-1));
706 assert(valueMatches(basicType(sig.charAt(i)), pt, av[i]));
707 }
708 return true;
709 }
710 private static boolean valueMatches(BasicType tc, Class<?> type, Object x) {
711 // The following line is needed because (...)void method handles can use non-void invokers
712 if (type == void.class) tc = V_TYPE; // can drop any kind of value
713 assert tc == basicType(type) : tc + " == basicType(" + type + ")=" + basicType(type);
714 switch (tc) {
715 case I_TYPE: assert checkInt(type, x) : "checkInt(" + type + "," + x +")"; break;
716 case J_TYPE: assert x instanceof Long : "instanceof Long: " + x; break;
717 case F_TYPE: assert x instanceof Float : "instanceof Float: " + x; break;
718 case D_TYPE: assert x instanceof Double : "instanceof Double: " + x; break;
719 case L_TYPE: assert checkRef(type, x) : "checkRef(" + type + "," + x + ")"; break;
720 case V_TYPE: break; // allow anything here; will be dropped
721 default: assert(false);
722 }
723 return true;
724 }
725 private static boolean returnTypesMatch(String sig, Object[] av, Object res) {
726 MethodHandle mh = (MethodHandle) av[0];
727 return valueMatches(signatureReturn(sig), mh.type().returnType(), res);
728 }
729 private static boolean checkInt(Class<?> type, Object x) {
730 assert(x instanceof Integer);
731 if (type == int.class) return true;
732 Wrapper w = Wrapper.forBasicType(type);
733 assert(w.isSubwordOrInt());
734 Object x1 = Wrapper.INT.wrap(w.wrap(x));
735 return x.equals(x1);
736 }
737 private static boolean checkRef(Class<?> type, Object x) {
738 assert(!type.isPrimitive());
739 if (x == null) return true;
740 if (type.isInterface()) return true;
741 return type.isInstance(x);
742 }
743
744 /** If the invocation count hits the threshold we spin bytecodes and call that subsequently. */
745 private static final int COMPILE_THRESHOLD;
746 static {
747 COMPILE_THRESHOLD = Math.max(-1, MethodHandleStatics.COMPILE_THRESHOLD);
748 }
749 private int invocationCounter = 0;
750
751 @Hidden
752 @DontInline
753 /** Interpretively invoke this form on the given arguments. */
754 Object interpretWithArguments(Object... argumentValues) throws Throwable {
755 if (TRACE_INTERPRETER)
756 return interpretWithArgumentsTracing(argumentValues);
757 checkInvocationCounter();
758 assert(arityCheck(argumentValues));
759 Object[] values = Arrays.copyOf(argumentValues, names.length);
760 for (int i = argumentValues.length; i < values.length; i++) {
761 values[i] = interpretName(names[i], values);
762 }
763 Object rv = (result < 0) ? null : values[result];
764 assert(resultCheck(argumentValues, rv));
765 return rv;
766 }
767
768 @Hidden
769 @DontInline
770 /** Evaluate a single Name within this form, applying its function to its arguments. */
771 Object interpretName(Name name, Object[] values) throws Throwable {
772 if (TRACE_INTERPRETER)
773 traceInterpreter("| interpretName", name.debugString(), (Object[]) null);
774 Object[] arguments = Arrays.copyOf(name.arguments, name.arguments.length, Object[].class);
775 for (int i = 0; i < arguments.length; i++) {
776 Object a = arguments[i];
777 if (a instanceof Name) {
778 int i2 = ((Name)a).index();
779 assert(names[i2] == a);
780 a = values[i2];
781 arguments[i] = a;
782 }
783 }
784 return name.function.invokeWithArguments(arguments);
785 }
786
787 private void checkInvocationCounter() {
788 if (COMPILE_THRESHOLD != 0 &&
789 invocationCounter < COMPILE_THRESHOLD) {
790 invocationCounter++; // benign race
791 if (invocationCounter >= COMPILE_THRESHOLD) {
792 // Replace vmentry with a bytecode version of this LF.
793 compileToBytecode();
794 }
795 }
796 }
797 Object interpretWithArgumentsTracing(Object... argumentValues) throws Throwable {
798 traceInterpreter("[ interpretWithArguments", this, argumentValues);
799 if (invocationCounter < COMPILE_THRESHOLD) {
800 int ctr = invocationCounter++; // benign race
801 traceInterpreter("| invocationCounter", ctr);
802 if (invocationCounter >= COMPILE_THRESHOLD) {
803 compileToBytecode();
804 }
805 }
806 Object rval;
807 try {
808 assert(arityCheck(argumentValues));
809 Object[] values = Arrays.copyOf(argumentValues, names.length);
810 for (int i = argumentValues.length; i < values.length; i++) {
811 values[i] = interpretName(names[i], values);
812 }
813 rval = (result < 0) ? null : values[result];
814 } catch (Throwable ex) {
815 traceInterpreter("] throw =>", ex);
816 throw ex;
817 }
818 traceInterpreter("] return =>", rval);
819 return rval;
820 }
821
822 static void traceInterpreter(String event, Object obj, Object... args) {
823 if (TRACE_INTERPRETER) {
824 System.out.println("LFI: "+event+" "+(obj != null ? obj : "")+(args != null && args.length != 0 ? Arrays.asList(args) : ""));
825 }
826 }
827 static void traceInterpreter(String event, Object obj) {
828 traceInterpreter(event, obj, (Object[])null);
829 }
830 private boolean arityCheck(Object[] argumentValues) {
831 assert(argumentValues.length == arity) : arity+"!="+Arrays.asList(argumentValues)+".length";
832 // also check that the leading (receiver) argument is somehow bound to this LF:
833 assert(argumentValues[0] instanceof MethodHandle) : "not MH: " + argumentValues[0];
834 MethodHandle mh = (MethodHandle) argumentValues[0];
835 assert(mh.internalForm() == this);
836 // note: argument #0 could also be an interface wrapper, in the future
837 argumentTypesMatch(basicTypeSignature(), argumentValues);
838 return true;
839 }
840 private boolean resultCheck(Object[] argumentValues, Object result) {
841 MethodHandle mh = (MethodHandle) argumentValues[0];
842 MethodType mt = mh.type();
843 assert(valueMatches(returnType(), mt.returnType(), result));
844 return true;
845 }
846
847 private boolean isEmpty() {
848 if (result < 0)
849 return (names.length == arity);
850 else if (result == arity && names.length == arity + 1)
851 return names[arity].isConstantZero();
852 else
853 return false;
854 }
855
856 public String toString() {
857 StringBuilder buf = new StringBuilder(debugName+"=Lambda(");
858 for (int i = 0; i < names.length; i++) {
859 if (i == arity) buf.append(")=>{");
860 Name n = names[i];
861 if (i >= arity) buf.append("\n ");
862 buf.append(n.paramString());
863 if (i < arity) {
864 if (i+1 < arity) buf.append(",");
865 continue;
866 }
867 buf.append("=").append(n.exprString());
868 buf.append(";");
869 }
870 if (arity == names.length) buf.append(")=>{");
871 buf.append(result < 0 ? "void" : names[result]).append("}");
872 if (TRACE_INTERPRETER) {
873 // Extra verbosity:
874 buf.append(":").append(basicTypeSignature());
875 buf.append("/").append(vmentry);
876 }
877 return buf.toString();
878 }
879
880 @Override
881 public boolean equals(Object obj) {
882 return obj instanceof LambdaForm && equals((LambdaForm)obj);
883 }
884 public boolean equals(LambdaForm that) {
885 if (this.result != that.result) return false;
886 return Arrays.equals(this.names, that.names);
887 }
888 public int hashCode() {
889 return result + 31 * Arrays.hashCode(names);
890 }
891 LambdaFormEditor editor() {
892 return LambdaFormEditor.lambdaFormEditor(this);
893 }
894
895 boolean contains(Name name) {
896 int pos = name.index();
897 if (pos >= 0) {
898 return pos < names.length && name.equals(names[pos]);
899 }
900 for (int i = arity; i < names.length; i++) {
901 if (name.equals(names[i]))
902 return true;
903 }
904 return false;
905 }
906
907 LambdaForm addArguments(int pos, BasicType... types) {
908 // names array has MH in slot 0; skip it.
909 int argpos = pos + 1;
910 assert(argpos <= arity);
911 int length = names.length;
912 int inTypes = types.length;
913 Name[] names2 = Arrays.copyOf(names, length + inTypes);
914 int arity2 = arity + inTypes;
915 int result2 = result;
916 if (result2 >= argpos)
917 result2 += inTypes;
918 // Note: The LF constructor will rename names2[argpos...].
919 // Make space for new arguments (shift temporaries).
920 System.arraycopy(names, argpos, names2, argpos + inTypes, length - argpos);
921 for (int i = 0; i < inTypes; i++) {
922 names2[argpos + i] = new Name(types[i]);
923 }
924 return new LambdaForm(debugName, arity2, names2, result2);
925 }
926
927 LambdaForm addArguments(int pos, List<Class<?>> types) {
928 return addArguments(pos, basicTypes(types));
929 }
930
931 LambdaForm permuteArguments(int skip, int[] reorder, BasicType[] types) {
932 // Note: When inArg = reorder[outArg], outArg is fed by a copy of inArg.
933 // The types are the types of the new (incoming) arguments.
934 int length = names.length;
935 int inTypes = types.length;
936 int outArgs = reorder.length;
937 assert(skip+outArgs == arity);
938 assert(permutedTypesMatch(reorder, types, names, skip));
939 int pos = 0;
940 // skip trivial first part of reordering:
941 while (pos < outArgs && reorder[pos] == pos) pos += 1;
942 Name[] names2 = new Name[length - outArgs + inTypes];
943 System.arraycopy(names, 0, names2, 0, skip+pos);
944 // copy the body:
945 int bodyLength = length - arity;
946 System.arraycopy(names, skip+outArgs, names2, skip+inTypes, bodyLength);
947 int arity2 = names2.length - bodyLength;
948 int result2 = result;
949 if (result2 >= 0) {
950 if (result2 < skip+outArgs) {
951 // return the corresponding inArg
952 result2 = reorder[result2-skip];
953 } else {
954 result2 = result2 - outArgs + inTypes;
955 }
956 }
957 // rework names in the body:
958 for (int j = pos; j < outArgs; j++) {
959 Name n = names[skip+j];
960 int i = reorder[j];
961 // replace names[skip+j] by names2[skip+i]
962 Name n2 = names2[skip+i];
963 if (n2 == null)
964 names2[skip+i] = n2 = new Name(types[i]);
965 else
966 assert(n2.type == types[i]);
967 for (int k = arity2; k < names2.length; k++) {
968 names2[k] = names2[k].replaceName(n, n2);
969 }
970 }
971 // some names are unused, but must be filled in
972 for (int i = skip+pos; i < arity2; i++) {
973 if (names2[i] == null)
974 names2[i] = argument(i, types[i - skip]);
975 }
976 for (int j = arity; j < names.length; j++) {
977 int i = j - arity + arity2;
978 // replace names2[i] by names[j]
979 Name n = names[j];
980 Name n2 = names2[i];
981 if (n != n2) {
982 for (int k = i+1; k < names2.length; k++) {
983 names2[k] = names2[k].replaceName(n, n2);
984 }
985 }
986 }
987 return new LambdaForm(debugName, arity2, names2, result2);
988 }
989
990 static boolean permutedTypesMatch(int[] reorder, BasicType[] types, Name[] names, int skip) {
991 int inTypes = types.length;
992 int outArgs = reorder.length;
993 for (int i = 0; i < outArgs; i++) {
994 assert(names[skip+i].isParam());
995 assert(names[skip+i].type == types[reorder[i]]);
996 }
997 return true;
998 }
999
1000 static class NamedFunction {
1001 final MemberName member;
1002 @Stable MethodHandle resolvedHandle;
1003 @Stable MethodHandle invoker;
1004
1005 NamedFunction(MethodHandle resolvedHandle) {
1006 this(resolvedHandle.internalMemberName(), resolvedHandle);
1007 }
1008 NamedFunction(MemberName member, MethodHandle resolvedHandle) {
1009 this.member = member;
1010 this.resolvedHandle = resolvedHandle;
1011 // The following assert is almost always correct, but will fail for corner cases, such as PrivateInvokeTest.
1012 //assert(!isInvokeBasic());
1013 }
1014 NamedFunction(MethodType basicInvokerType) {
1015 assert(basicInvokerType == basicInvokerType.basicType()) : basicInvokerType;
1016 if (basicInvokerType.parameterSlotCount() < MethodType.MAX_MH_INVOKER_ARITY) {
1017 this.resolvedHandle = basicInvokerType.invokers().basicInvoker();
1018 this.member = resolvedHandle.internalMemberName();
1019 } else {
1020 // necessary to pass BigArityTest
1021 this.member = Invokers.invokeBasicMethod(basicInvokerType);
1022 }
1023 assert(isInvokeBasic());
1024 }
1025
1026 private boolean isInvokeBasic() {
1027 return member != null &&
1028 member.isMethodHandleInvoke() &&
1029 "invokeBasic".equals(member.getName());
1030 }
1031
1032 // The next 3 constructors are used to break circular dependencies on MH.invokeStatic, etc.
1033 // Any LambdaForm containing such a member is not interpretable.
1034 // This is OK, since all such LFs are prepared with special primitive vmentry points.
1035 // And even without the resolvedHandle, the name can still be compiled and optimized.
1036 NamedFunction(Method method) {
1037 this(MemberName.make(method));
1038 }
1039 NamedFunction(Field field) {
1040 this(MemberName.make(field));
1041 }
1042 NamedFunction(MemberName member) {
1043 this.member = member;
1044 this.resolvedHandle = null;
1045 }
1046
1047 MethodHandle resolvedHandle() {
1048 if (resolvedHandle == null) resolve();
1049 return resolvedHandle;
1050 }
1051
1052 void resolve() {
1053 resolvedHandle = DirectMethodHandle.make(member);
1054 }
1055
1056 @Override
1057 public boolean equals(Object other) {
1058 if (this == other) return true;
1059 if (other == null) return false;
1060 if (!(other instanceof NamedFunction)) return false;
1061 NamedFunction that = (NamedFunction) other;
1062 return this.member != null && this.member.equals(that.member);
1063 }
1064
1065 @Override
1066 public int hashCode() {
1067 if (member != null)
1068 return member.hashCode();
1069 return super.hashCode();
1070 }
1071
1072 // Put the predefined NamedFunction invokers into the table.
1073 static void initializeInvokers() {
1074 for (MemberName m : MemberName.getFactory().getMethods(NamedFunction.class, false, null, null, null)) {
1075 if (!m.isStatic() || !m.isPackage()) continue;
1076 MethodType type = m.getMethodType();
1077 if (type.equals(INVOKER_METHOD_TYPE) &&
1078 m.getName().startsWith("invoke_")) {
1079 String sig = m.getName().substring("invoke_".length());
1080 int arity = LambdaForm.signatureArity(sig);
1081 MethodType srcType = MethodType.genericMethodType(arity);
1082 if (LambdaForm.signatureReturn(sig) == V_TYPE)
1083 srcType = srcType.changeReturnType(void.class);
1084 MethodTypeForm typeForm = srcType.form();
1085 typeForm.setCachedMethodHandle(MethodTypeForm.MH_NF_INV, DirectMethodHandle.make(m));
1086 }
1087 }
1088 }
1089
1090 // The following are predefined NamedFunction invokers. The system must build
1091 // a separate invoker for each distinct signature.
1092 /** void return type invokers. */
1093 @Hidden
1094 static Object invoke__V(MethodHandle mh, Object[] a) throws Throwable {
1095 assert(arityCheck(0, void.class, mh, a));
1096 mh.invokeBasic();
1097 return null;
1098 }
1099 @Hidden
1100 static Object invoke_L_V(MethodHandle mh, Object[] a) throws Throwable {
1101 assert(arityCheck(1, void.class, mh, a));
1102 mh.invokeBasic(a[0]);
1103 return null;
1104 }
1105 @Hidden
1106 static Object invoke_LL_V(MethodHandle mh, Object[] a) throws Throwable {
1107 assert(arityCheck(2, void.class, mh, a));
1108 mh.invokeBasic(a[0], a[1]);
1109 return null;
1110 }
1111 @Hidden
1112 static Object invoke_LLL_V(MethodHandle mh, Object[] a) throws Throwable {
1113 assert(arityCheck(3, void.class, mh, a));
1114 mh.invokeBasic(a[0], a[1], a[2]);
1115 return null;
1116 }
1117 @Hidden
1118 static Object invoke_LLLL_V(MethodHandle mh, Object[] a) throws Throwable {
1119 assert(arityCheck(4, void.class, mh, a));
1120 mh.invokeBasic(a[0], a[1], a[2], a[3]);
1121 return null;
1122 }
1123 @Hidden
1124 static Object invoke_LLLLL_V(MethodHandle mh, Object[] a) throws Throwable {
1125 assert(arityCheck(5, void.class, mh, a));
1126 mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]);
1127 return null;
1128 }
1129 /** Object return type invokers. */
1130 @Hidden
1131 static Object invoke__L(MethodHandle mh, Object[] a) throws Throwable {
1132 assert(arityCheck(0, mh, a));
1133 return mh.invokeBasic();
1134 }
1135 @Hidden
1136 static Object invoke_L_L(MethodHandle mh, Object[] a) throws Throwable {
1137 assert(arityCheck(1, mh, a));
1138 return mh.invokeBasic(a[0]);
1139 }
1140 @Hidden
1141 static Object invoke_LL_L(MethodHandle mh, Object[] a) throws Throwable {
1142 assert(arityCheck(2, mh, a));
1143 return mh.invokeBasic(a[0], a[1]);
1144 }
1145 @Hidden
1146 static Object invoke_LLL_L(MethodHandle mh, Object[] a) throws Throwable {
1147 assert(arityCheck(3, mh, a));
1148 return mh.invokeBasic(a[0], a[1], a[2]);
1149 }
1150 @Hidden
1151 static Object invoke_LLLL_L(MethodHandle mh, Object[] a) throws Throwable {
1152 assert(arityCheck(4, mh, a));
1153 return mh.invokeBasic(a[0], a[1], a[2], a[3]);
1154 }
1155 @Hidden
1156 static Object invoke_LLLLL_L(MethodHandle mh, Object[] a) throws Throwable {
1157 assert(arityCheck(5, mh, a));
1158 return mh.invokeBasic(a[0], a[1], a[2], a[3], a[4]);
1159 }
1160 private static boolean arityCheck(int arity, MethodHandle mh, Object[] a) {
1161 return arityCheck(arity, Object.class, mh, a);
1162 }
1163 private static boolean arityCheck(int arity, Class<?> rtype, MethodHandle mh, Object[] a) {
1164 assert(a.length == arity)
1165 : Arrays.asList(a.length, arity);
1166 assert(mh.type().basicType() == MethodType.genericMethodType(arity).changeReturnType(rtype))
1167 : Arrays.asList(mh, rtype, arity);
1168 MemberName member = mh.internalMemberName();
1169 if (member != null && member.getName().equals("invokeBasic") && member.isMethodHandleInvoke()) {
1170 assert(arity > 0);
1171 assert(a[0] instanceof MethodHandle);
1172 MethodHandle mh2 = (MethodHandle) a[0];
1173 assert(mh2.type().basicType() == MethodType.genericMethodType(arity-1).changeReturnType(rtype))
1174 : Arrays.asList(member, mh2, rtype, arity);
1175 }
1176 return true;
1177 }
1178
1179 static final MethodType INVOKER_METHOD_TYPE =
1180 MethodType.methodType(Object.class, MethodHandle.class, Object[].class);
1181
1182 private static MethodHandle computeInvoker(MethodTypeForm typeForm) {
1183 typeForm = typeForm.basicType().form(); // normalize to basic type
1184 MethodHandle mh = typeForm.cachedMethodHandle(MethodTypeForm.MH_NF_INV);
1185 if (mh != null) return mh;
1186 MemberName invoker = InvokerBytecodeGenerator.generateNamedFunctionInvoker(typeForm); // this could take a while
1187 mh = DirectMethodHandle.make(invoker);
1188 MethodHandle mh2 = typeForm.cachedMethodHandle(MethodTypeForm.MH_NF_INV);
1189 if (mh2 != null) return mh2; // benign race
1190 if (!mh.type().equals(INVOKER_METHOD_TYPE))
1191 throw newInternalError(mh.debugString());
1192 return typeForm.setCachedMethodHandle(MethodTypeForm.MH_NF_INV, mh);
1193 }
1194
1195 @Hidden
1196 Object invokeWithArguments(Object... arguments) throws Throwable {
1197 // If we have a cached invoker, call it right away.
1198 // NOTE: The invoker always returns a reference value.
1199 if (TRACE_INTERPRETER) return invokeWithArgumentsTracing(arguments);
1200 assert(checkArgumentTypes(arguments, methodType()));
1201 return invoker().invokeBasic(resolvedHandle(), arguments);
1202 }
1203
1204 @Hidden
1205 Object invokeWithArgumentsTracing(Object[] arguments) throws Throwable {
1206 Object rval;
1207 try {
1208 traceInterpreter("[ call", this, arguments);
1209 if (invoker == null) {
1210 traceInterpreter("| getInvoker", this);
1211 invoker();
1212 }
1213 if (resolvedHandle == null) {
1214 traceInterpreter("| resolve", this);
1215 resolvedHandle();
1216 }
1217 assert(checkArgumentTypes(arguments, methodType()));
1218 rval = invoker().invokeBasic(resolvedHandle(), arguments);
1219 } catch (Throwable ex) {
1220 traceInterpreter("] throw =>", ex);
1221 throw ex;
1222 }
1223 traceInterpreter("] return =>", rval);
1224 return rval;
1225 }
1226
1227 private MethodHandle invoker() {
1228 if (invoker != null) return invoker;
1229 // Get an invoker and cache it.
1230 return invoker = computeInvoker(methodType().form());
1231 }
1232
1233 private static boolean checkArgumentTypes(Object[] arguments, MethodType methodType) {
1234 if (true) return true; // FIXME
1235 MethodType dstType = methodType.form().erasedType();
1236 MethodType srcType = dstType.basicType().wrap();
1237 Class<?>[] ptypes = new Class<?>[arguments.length];
1238 for (int i = 0; i < arguments.length; i++) {
1239 Object arg = arguments[i];
1240 Class<?> ptype = arg == null ? Object.class : arg.getClass();
1241 // If the dest. type is a primitive we keep the
1242 // argument type.
1243 ptypes[i] = dstType.parameterType(i).isPrimitive() ? ptype : Object.class;
1244 }
1245 MethodType argType = MethodType.methodType(srcType.returnType(), ptypes).wrap();
1246 assert(argType.isConvertibleTo(srcType)) : "wrong argument types: cannot convert " + argType + " to " + srcType;
1247 return true;
1248 }
1249
1250 MethodType methodType() {
1251 if (resolvedHandle != null)
1252 return resolvedHandle.type();
1253 else
1254 // only for certain internal LFs during bootstrapping
1255 return member.getInvocationType();
1256 }
1257
1258 MemberName member() {
1259 assert(assertMemberIsConsistent());
1260 return member;
1261 }
1262
1263 // Called only from assert.
1264 private boolean assertMemberIsConsistent() {
1265 if (resolvedHandle instanceof DirectMethodHandle) {
1266 MemberName m = resolvedHandle.internalMemberName();
1267 assert(m.equals(member));
1268 }
1269 return true;
1270 }
1271
1272 Class<?> memberDeclaringClassOrNull() {
1273 return (member == null) ? null : member.getDeclaringClass();
1274 }
1275
1276 BasicType returnType() {
1277 return basicType(methodType().returnType());
1278 }
1279
1280 BasicType parameterType(int n) {
1281 return basicType(methodType().parameterType(n));
1282 }
1283
1284 int arity() {
1285 return methodType().parameterCount();
1286 }
1287
1288 public String toString() {
1289 if (member == null) return String.valueOf(resolvedHandle);
1290 return member.getDeclaringClass().getSimpleName()+"."+member.getName();
1291 }
1292
1293 public boolean isIdentity() {
1294 return this.equals(identity(returnType()));
1295 }
1296
1297 public boolean isConstantZero() {
1298 return this.equals(constantZero(returnType()));
1299 }
1300
1301 public MethodHandleImpl.Intrinsic intrinsicName() {
1302 return resolvedHandle == null ? MethodHandleImpl.Intrinsic.NONE
1303 : resolvedHandle.intrinsicName();
1304 }
1305 }
1306
1307 public static String basicTypeSignature(MethodType type) {
1308 char[] sig = new char[type.parameterCount() + 2];
1309 int sigp = 0;
1310 for (Class<?> pt : type.parameterList()) {
1311 sig[sigp++] = basicTypeChar(pt);
1312 }
1313 sig[sigp++] = '_';
1314 sig[sigp++] = basicTypeChar(type.returnType());
1315 assert(sigp == sig.length);
1316 return String.valueOf(sig);
1317 }
1318 public static String shortenSignature(String signature) {
1319 // Hack to make signatures more readable when they show up in method names.
1320 final int NO_CHAR = -1, MIN_RUN = 3;
1321 int c0, c1 = NO_CHAR, c1reps = 0;
1322 StringBuilder buf = null;
1323 int len = signature.length();
1324 if (len < MIN_RUN) return signature;
1325 for (int i = 0; i <= len; i++) {
1326 // shift in the next char:
1327 c0 = c1; c1 = (i == len ? NO_CHAR : signature.charAt(i));
1328 if (c1 == c0) { ++c1reps; continue; }
1329 // shift in the next count:
1330 int c0reps = c1reps; c1reps = 1;
1331 // end of a character run
1332 if (c0reps < MIN_RUN) {
1333 if (buf != null) {
1334 while (--c0reps >= 0)
1335 buf.append((char)c0);
1336 }
1337 continue;
1338 }
1339 // found three or more in a row
1340 if (buf == null)
1341 buf = new StringBuilder().append(signature, 0, i - c0reps);
1342 buf.append((char)c0).append(c0reps);
1343 }
1344 return (buf == null) ? signature : buf.toString();
1345 }
1346
1347 static final class Name {
1348 final BasicType type;
1349 private short index;
1350 final NamedFunction function;
1351 final Object constraint; // additional type information, if not null
1352 @Stable final Object[] arguments;
1353
1354 private Name(int index, BasicType type, NamedFunction function, Object[] arguments) {
1355 this.index = (short)index;
1356 this.type = type;
1357 this.function = function;
1358 this.arguments = arguments;
1359 this.constraint = null;
1360 assert(this.index == index);
1361 }
1362 private Name(Name that, Object constraint) {
1363 this.index = that.index;
1364 this.type = that.type;
1365 this.function = that.function;
1366 this.arguments = that.arguments;
1367 this.constraint = constraint;
1368 assert(constraint == null || isParam()); // only params have constraints
1369 assert(constraint == null || constraint instanceof BoundMethodHandle.SpeciesData || constraint instanceof Class);
1370 }
1371 Name(MethodHandle function, Object... arguments) {
1372 this(new NamedFunction(function), arguments);
1373 }
1374 Name(MethodType functionType, Object... arguments) {
1375 this(new NamedFunction(functionType), arguments);
1376 assert(arguments[0] instanceof Name && ((Name)arguments[0]).type == L_TYPE);
1377 }
1378 Name(MemberName function, Object... arguments) {
1379 this(new NamedFunction(function), arguments);
1380 }
1381 Name(NamedFunction function, Object... arguments) {
1382 this(-1, function.returnType(), function, arguments = Arrays.copyOf(arguments, arguments.length, Object[].class));
1383 assert(arguments.length == function.arity()) : "arity mismatch: arguments.length=" + arguments.length + " == function.arity()=" + function.arity() + " in " + debugString();
1384 for (int i = 0; i < arguments.length; i++)
1385 assert(typesMatch(function.parameterType(i), arguments[i])) : "types don't match: function.parameterType(" + i + ")=" + function.parameterType(i) + ", arguments[" + i + "]=" + arguments[i] + " in " + debugString();
1386 }
1387 /** Create a raw parameter of the given type, with an expected index. */
1388 Name(int index, BasicType type) {
1389 this(index, type, null, null);
1390 }
1391 /** Create a raw parameter of the given type. */
1392 Name(BasicType type) { this(-1, type); }
1393
1394 BasicType type() { return type; }
1395 int index() { return index; }
1396 boolean initIndex(int i) {
1397 if (index != i) {
1398 if (index != -1) return false;
1399 index = (short)i;
1400 }
1401 return true;
1402 }
1403 char typeChar() {
1404 return type.btChar;
1405 }
1406
1407 void resolve() {
1408 if (function != null)
1409 function.resolve();
1410 }
1411
1412 Name newIndex(int i) {
1413 if (initIndex(i)) return this;
1414 return cloneWithIndex(i);
1415 }
1416 Name cloneWithIndex(int i) {
1417 Object[] newArguments = (arguments == null) ? null : arguments.clone();
1418 return new Name(i, type, function, newArguments).withConstraint(constraint);
1419 }
1420 Name withConstraint(Object constraint) {
1421 if (constraint == this.constraint) return this;
1422 return new Name(this, constraint);
1423 }
1424 Name replaceName(Name oldName, Name newName) { // FIXME: use replaceNames uniformly
1425 if (oldName == newName) return this;
1426 @SuppressWarnings("LocalVariableHidesMemberVariable")
1427 Object[] arguments = this.arguments;
1428 if (arguments == null) return this;
1429 boolean replaced = false;
1430 for (int j = 0; j < arguments.length; j++) {
1431 if (arguments[j] == oldName) {
1432 if (!replaced) {
1433 replaced = true;
1434 arguments = arguments.clone();
1435 }
1436 arguments[j] = newName;
1437 }
1438 }
1439 if (!replaced) return this;
1440 return new Name(function, arguments);
1441 }
1442 /** In the arguments of this Name, replace oldNames[i] pairwise by newNames[i].
1443 * Limit such replacements to {@code start<=i<end}. Return possibly changed self.
1444 */
1445 Name replaceNames(Name[] oldNames, Name[] newNames, int start, int end) {
1446 if (start >= end) return this;
1447 @SuppressWarnings("LocalVariableHidesMemberVariable")
1448 Object[] arguments = this.arguments;
1449 boolean replaced = false;
1450 eachArg:
1451 for (int j = 0; j < arguments.length; j++) {
1452 if (arguments[j] instanceof Name) {
1453 Name n = (Name) arguments[j];
1454 int check = n.index;
1455 // harmless check to see if the thing is already in newNames:
1456 if (check >= 0 && check < newNames.length && n == newNames[check])
1457 continue eachArg;
1458 // n might not have the correct index: n != oldNames[n.index].
1459 for (int i = start; i < end; i++) {
1460 if (n == oldNames[i]) {
1461 if (n == newNames[i])
1462 continue eachArg;
1463 if (!replaced) {
1464 replaced = true;
1465 arguments = arguments.clone();
1466 }
1467 arguments[j] = newNames[i];
1468 continue eachArg;
1469 }
1470 }
1471 }
1472 }
1473 if (!replaced) return this;
1474 return new Name(function, arguments);
1475 }
1476 void internArguments() {
1477 @SuppressWarnings("LocalVariableHidesMemberVariable")
1478 Object[] arguments = this.arguments;
1479 for (int j = 0; j < arguments.length; j++) {
1480 if (arguments[j] instanceof Name) {
1481 Name n = (Name) arguments[j];
1482 if (n.isParam() && n.index < INTERNED_ARGUMENT_LIMIT)
1483 arguments[j] = internArgument(n);
1484 }
1485 }
1486 }
1487 boolean isParam() {
1488 return function == null;
1489 }
1490 boolean isConstantZero() {
1491 return !isParam() && arguments.length == 0 && function.isConstantZero();
1492 }
1493
1494 public String toString() {
1495 return (isParam()?"a":"t")+(index >= 0 ? index : System.identityHashCode(this))+":"+typeChar();
1496 }
1497 public String debugString() {
1498 String s = paramString();
1499 return (function == null) ? s : s + "=" + exprString();
1500 }
1501 public String paramString() {
1502 String s = toString();
1503 Object c = constraint;
1504 if (c == null)
1505 return s;
1506 if (c instanceof Class) c = ((Class<?>)c).getSimpleName();
1507 return s + "/" + c;
1508 }
1509 public String exprString() {
1510 if (function == null) return toString();
1511 StringBuilder buf = new StringBuilder(function.toString());
1512 buf.append("(");
1513 String cma = "";
1514 for (Object a : arguments) {
1515 buf.append(cma); cma = ",";
1516 if (a instanceof Name || a instanceof Integer)
1517 buf.append(a);
1518 else
1519 buf.append("(").append(a).append(")");
1520 }
1521 buf.append(")");
1522 return buf.toString();
1523 }
1524
1525 static boolean typesMatch(BasicType parameterType, Object object) {
1526 if (object instanceof Name) {
1527 return ((Name)object).type == parameterType;
1528 }
1529 switch (parameterType) {
1530 case I_TYPE: return object instanceof Integer;
1531 case J_TYPE: return object instanceof Long;
1532 case F_TYPE: return object instanceof Float;
1533 case D_TYPE: return object instanceof Double;
1534 }
1535 assert(parameterType == L_TYPE);
1536 return true;
1537 }
1538
1539 /** Return the index of the last occurrence of n in the argument array.
1540 * Return -1 if the name is not used.
1541 */
1542 int lastUseIndex(Name n) {
1543 if (arguments == null) return -1;
1544 for (int i = arguments.length; --i >= 0; ) {
1545 if (arguments[i] == n) return i;
1546 }
1547 return -1;
1548 }
1549
1550 /** Return the number of occurrences of n in the argument array.
1551 * Return 0 if the name is not used.
1552 */
1553 int useCount(Name n) {
1554 if (arguments == null) return 0;
1555 int count = 0;
1556 for (int i = arguments.length; --i >= 0; ) {
1557 if (arguments[i] == n) ++count;
1558 }
1559 return count;
1560 }
1561
1562 boolean contains(Name n) {
1563 return this == n || lastUseIndex(n) >= 0;
1564 }
1565
1566 public boolean equals(Name that) {
1567 if (this == that) return true;
1568 if (isParam())
1569 // each parameter is a unique atom
1570 return false; // this != that
1571 return
1572 //this.index == that.index &&
1573 this.type == that.type &&
1574 this.function.equals(that.function) &&
1575 Arrays.equals(this.arguments, that.arguments);
1576 }
1577 @Override
1578 public boolean equals(Object x) {
1579 return x instanceof Name && equals((Name)x);
1580 }
1581 @Override
1582 public int hashCode() {
1583 if (isParam())
1584 return index | (type.ordinal() << 8);
1585 return function.hashCode() ^ Arrays.hashCode(arguments);
1586 }
1587 }
1588
1589 /** Return the index of the last name which contains n as an argument.
1590 * Return -1 if the name is not used. Return names.length if it is the return value.
1591 */
1592 int lastUseIndex(Name n) {
1593 int ni = n.index, nmax = names.length;
1594 assert(names[ni] == n);
1595 if (result == ni) return nmax; // live all the way beyond the end
1596 for (int i = nmax; --i > ni; ) {
1597 if (names[i].lastUseIndex(n) >= 0)
1598 return i;
1599 }
1600 return -1;
1601 }
1602
1603 /** Return the number of times n is used as an argument or return value. */
1604 int useCount(Name n) {
1605 int ni = n.index, nmax = names.length;
1606 int end = lastUseIndex(n);
1607 if (end < 0) return 0;
1608 int count = 0;
1609 if (end == nmax) { count++; end--; }
1610 int beg = n.index() + 1;
1611 if (beg < arity) beg = arity;
1612 for (int i = beg; i <= end; i++) {
1613 count += names[i].useCount(n);
1614 }
1615 return count;
1616 }
1617
1618 static Name argument(int which, char type) {
1619 return argument(which, basicType(type));
1620 }
1621 static Name argument(int which, BasicType type) {
1622 if (which >= INTERNED_ARGUMENT_LIMIT)
1623 return new Name(which, type);
1624 return INTERNED_ARGUMENTS[type.ordinal()][which];
1625 }
1626 static Name internArgument(Name n) {
1627 assert(n.isParam()) : "not param: " + n;
1628 assert(n.index < INTERNED_ARGUMENT_LIMIT);
1629 if (n.constraint != null) return n;
1630 return argument(n.index, n.type);
1631 }
1632 static Name[] arguments(int extra, String types) {
1633 int length = types.length();
1634 Name[] names = new Name[length + extra];
1635 for (int i = 0; i < length; i++)
1636 names[i] = argument(i, types.charAt(i));
1637 return names;
1638 }
1639 static Name[] arguments(int extra, char... types) {
1640 int length = types.length;
1641 Name[] names = new Name[length + extra];
1642 for (int i = 0; i < length; i++)
1643 names[i] = argument(i, types[i]);
1644 return names;
1645 }
1646 static Name[] arguments(int extra, List<Class<?>> types) {
1647 int length = types.size();
1648 Name[] names = new Name[length + extra];
1649 for (int i = 0; i < length; i++)
1650 names[i] = argument(i, basicType(types.get(i)));
1651 return names;
1652 }
1653 static Name[] arguments(int extra, Class<?>... types) {
1654 int length = types.length;
1655 Name[] names = new Name[length + extra];
1656 for (int i = 0; i < length; i++)
1657 names[i] = argument(i, basicType(types[i]));
1658 return names;
1659 }
1660 static Name[] arguments(int extra, MethodType types) {
1661 int length = types.parameterCount();
1662 Name[] names = new Name[length + extra];
1663 for (int i = 0; i < length; i++)
1664 names[i] = argument(i, basicType(types.parameterType(i)));
1665 return names;
1666 }
1667 static final int INTERNED_ARGUMENT_LIMIT = 10;
1668 private static final Name[][] INTERNED_ARGUMENTS
1669 = new Name[ARG_TYPE_LIMIT][INTERNED_ARGUMENT_LIMIT];
1670 static {
1671 for (BasicType type : BasicType.ARG_TYPES) {
1672 int ord = type.ordinal();
1673 for (int i = 0; i < INTERNED_ARGUMENTS[ord].length; i++) {
1674 INTERNED_ARGUMENTS[ord][i] = new Name(i, type);
1675 }
1676 }
1677 }
1678
1679 private static final MemberName.Factory IMPL_NAMES = MemberName.getFactory();
1680
1681 static LambdaForm identityForm(BasicType type) {
1682 return LF_identityForm[type.ordinal()];
1683 }
1684 static LambdaForm zeroForm(BasicType type) {
1685 return LF_zeroForm[type.ordinal()];
1686 }
1687 static NamedFunction identity(BasicType type) {
1688 return NF_identity[type.ordinal()];
1689 }
1690 static NamedFunction constantZero(BasicType type) {
1691 return NF_zero[type.ordinal()];
1692 }
1693 private static final LambdaForm[] LF_identityForm = new LambdaForm[TYPE_LIMIT];
1694 private static final LambdaForm[] LF_zeroForm = new LambdaForm[TYPE_LIMIT];
1695 private static final NamedFunction[] NF_identity = new NamedFunction[TYPE_LIMIT];
1696 private static final NamedFunction[] NF_zero = new NamedFunction[TYPE_LIMIT];
1697 private static void createIdentityForms() {
1698 for (BasicType type : BasicType.ALL_TYPES) {
1699 int ord = type.ordinal();
1700 char btChar = type.basicTypeChar();
1701 boolean isVoid = (type == V_TYPE);
1702 Class<?> btClass = type.btClass;
1703 MethodType zeType = MethodType.methodType(btClass);
1704 MethodType idType = isVoid ? zeType : zeType.appendParameterTypes(btClass);
1705
1706 // Look up some symbolic names. It might not be necessary to have these,
1707 // but if we need to emit direct references to bytecodes, it helps.
1708 // Zero is built from a call to an identity function with a constant zero input.
1709 MemberName idMem = new MemberName(LambdaForm.class, "identity_"+btChar, idType, REF_invokeStatic);
1710 MemberName zeMem = new MemberName(LambdaForm.class, "zero_"+btChar, zeType, REF_invokeStatic);
1711 try {
1712 zeMem = IMPL_NAMES.resolveOrFail(REF_invokeStatic, zeMem, null, NoSuchMethodException.class);
1713 idMem = IMPL_NAMES.resolveOrFail(REF_invokeStatic, idMem, null, NoSuchMethodException.class);
1714 } catch (IllegalAccessException|NoSuchMethodException ex) {
1715 throw newInternalError(ex);
1716 }
1717
1718 NamedFunction idFun = new NamedFunction(idMem);
1719 LambdaForm idForm;
1720 if (isVoid) {
1721 Name[] idNames = new Name[] { argument(0, L_TYPE) };
1722 idForm = new LambdaForm(idMem.getName(), 1, idNames, VOID_RESULT);
1723 } else {
1724 Name[] idNames = new Name[] { argument(0, L_TYPE), argument(1, type) };
1725 idForm = new LambdaForm(idMem.getName(), 2, idNames, 1);
1726 }
1727 LF_identityForm[ord] = idForm;
1728 NF_identity[ord] = idFun;
1729
1730 NamedFunction zeFun = new NamedFunction(zeMem);
1731 LambdaForm zeForm;
1732 if (isVoid) {
1733 zeForm = idForm;
1734 } else {
1735 Object zeValue = Wrapper.forBasicType(btChar).zero();
1736 Name[] zeNames = new Name[] { argument(0, L_TYPE), new Name(idFun, zeValue) };
1737 zeForm = new LambdaForm(zeMem.getName(), 1, zeNames, 1);
1738 }
1739 LF_zeroForm[ord] = zeForm;
1740 NF_zero[ord] = zeFun;
1741
1742 assert(idFun.isIdentity());
1743 assert(zeFun.isConstantZero());
1744 assert(new Name(zeFun).isConstantZero());
1745 }
1746
1747 // Do this in a separate pass, so that SimpleMethodHandle.make can see the tables.
1748 for (BasicType type : BasicType.ALL_TYPES) {
1749 int ord = type.ordinal();
1750 NamedFunction idFun = NF_identity[ord];
1751 LambdaForm idForm = LF_identityForm[ord];
1752 MemberName idMem = idFun.member;
1753 idFun.resolvedHandle = SimpleMethodHandle.make(idMem.getInvocationType(), idForm);
1754
1755 NamedFunction zeFun = NF_zero[ord];
1756 LambdaForm zeForm = LF_zeroForm[ord];
1757 MemberName zeMem = zeFun.member;
1758 zeFun.resolvedHandle = SimpleMethodHandle.make(zeMem.getInvocationType(), zeForm);
1759
1760 assert(idFun.isIdentity());
1761 assert(zeFun.isConstantZero());
1762 assert(new Name(zeFun).isConstantZero());
1763 }
1764 }
1765
1766 // Avoid appealing to ValueConversions at bootstrap time:
1767 private static int identity_I(int x) { return x; }
1768 private static long identity_J(long x) { return x; }
1769 private static float identity_F(float x) { return x; }
1770 private static double identity_D(double x) { return x; }
1771 private static Object identity_L(Object x) { return x; }
1772 private static void identity_V() { return; } // same as zeroV, but that's OK
1773 private static int zero_I() { return 0; }
1774 private static long zero_J() { return 0; }
1775 private static float zero_F() { return 0; }
1776 private static double zero_D() { return 0; }
1777 private static Object zero_L() { return null; }
1778 private static void zero_V() { return; }
1779
1780 /**
1781 * Internal marker for byte-compiled LambdaForms.
1782 */
1783 /*non-public*/
1784 @Target(ElementType.METHOD)
1785 @Retention(RetentionPolicy.RUNTIME)
1786 @interface Compiled {
1787 }
1788
1789 /**
1790 * Internal marker for LambdaForm interpreter frames.
1791 */
1792 /*non-public*/
1793 @Target(ElementType.METHOD)
1794 @Retention(RetentionPolicy.RUNTIME)
1795 @interface Hidden {
1796 }
1797
1798 private static final HashMap<String,Integer> DEBUG_NAME_COUNTERS;
1799 static {
1800 if (debugEnabled())
1801 DEBUG_NAME_COUNTERS = new HashMap<>();
1802 else
1803 DEBUG_NAME_COUNTERS = null;
1804 }
1805
1806 // Put this last, so that previous static inits can run before.
1807 static {
1808 createIdentityForms();
1809 if (USE_PREDEFINED_INTERPRET_METHODS)
1810 computeInitialPreparedForms();
1811 NamedFunction.initializeInvokers();
1812 }
1813
1814 // The following hack is necessary in order to suppress TRACE_INTERPRETER
1815 // during execution of the static initializes of this class.
1816 // Turning on TRACE_INTERPRETER too early will cause
1817 // stack overflows and other misbehavior during attempts to trace events
1818 // that occur during LambdaForm.<clinit>.
1819 // Therefore, do not move this line higher in this file, and do not remove.
1820 private static final boolean TRACE_INTERPRETER = MethodHandleStatics.TRACE_INTERPRETER;
1821 }