1 /*
2 * Copyright (c) 2012, 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.io.*;
29 import java.util.*;
30 import java.lang.reflect.Modifier;
31
32 import jdk.internal.org.objectweb.asm.*;
33
34 import static java.lang.invoke.LambdaForm.*;
35 import static java.lang.invoke.LambdaForm.BasicType.*;
36 import static java.lang.invoke.MethodHandleStatics.*;
37 import static java.lang.invoke.MethodHandleNatives.Constants.*;
38 import sun.invoke.util.ValueConversions;
39 import sun.invoke.util.VerifyAccess;
40 import sun.invoke.util.VerifyType;
41 import sun.invoke.util.Wrapper;
42 import sun.reflect.misc.ReflectUtil;
43
44 /**
45 * Code generation backend for LambdaForm.
46 * <p>
47 * @author John Rose, JSR 292 EG
48 */
49 class InvokerBytecodeGenerator {
50 /** Define class names for convenience. */
51 private static final String MH = "java/lang/invoke/MethodHandle";
52 private static final String MHI = "java/lang/invoke/MethodHandleImpl";
53 private static final String LF = "java/lang/invoke/LambdaForm";
54 private static final String LFN = "java/lang/invoke/LambdaForm$Name";
55 private static final String CLS = "java/lang/Class";
56 private static final String OBJ = "java/lang/Object";
57 private static final String OBJARY = "[Ljava/lang/Object;";
58
59 private static final String LF_SIG = "L" + LF + ";";
60 private static final String LFN_SIG = "L" + LFN + ";";
61 private static final String LL_SIG = "(L" + OBJ + ";)L" + OBJ + ";";
62 private static final String CLL_SIG = "(L" + CLS + ";L" + OBJ + ";)L" + OBJ + ";";
63
64 /** Name of its super class*/
65 private static final String superName = LF;
66
67 /** Name of new class */
68 private final String className;
69
70 /** Name of the source file (for stack trace printing). */
71 private final String sourceFile;
72
73 private final LambdaForm lambdaForm;
74 private final String invokerName;
75 private final MethodType invokerType;
76
77 /** Info about local variables in compiled lambda form */
78 private final int[] localsMap; // index
79 private final BasicType[] localTypes; // basic type
80 private final Class<?>[] localClasses; // type
81
82 /** ASM bytecode generation. */
83 private ClassWriter cw;
84 private MethodVisitor mv;
85
86 private static final MemberName.Factory MEMBERNAME_FACTORY = MemberName.getFactory();
87 private static final Class<?> HOST_CLASS = LambdaForm.class;
88
89 /** Main constructor; other constructors delegate to this one. */
90 private InvokerBytecodeGenerator(LambdaForm lambdaForm, int localsMapSize,
91 String className, String invokerName, MethodType invokerType) {
92 if (invokerName.contains(".")) {
93 int p = invokerName.indexOf('.');
94 className = invokerName.substring(0, p);
95 invokerName = invokerName.substring(p+1);
96 }
97 if (DUMP_CLASS_FILES) {
98 className = makeDumpableClassName(className);
99 }
100 this.className = superName + "$" + className;
101 this.sourceFile = "LambdaForm$" + className;
102 this.lambdaForm = lambdaForm;
103 this.invokerName = invokerName;
104 this.invokerType = invokerType;
105 this.localsMap = new int[localsMapSize+1];
106 // last entry of localsMap is count of allocated local slots
107 this.localTypes = new BasicType[localsMapSize+1];
108 this.localClasses = new Class<?>[localsMapSize+1];
109 }
110
111 /** For generating LambdaForm interpreter entry points. */
112 private InvokerBytecodeGenerator(String className, String invokerName, MethodType invokerType) {
113 this(null, invokerType.parameterCount(),
114 className, invokerName, invokerType);
115 // Create an array to map name indexes to locals indexes.
116 localTypes[localTypes.length - 1] = V_TYPE;
117 for (int i = 0; i < localsMap.length; i++) {
118 localsMap[i] = invokerType.parameterSlotCount() - invokerType.parameterSlotDepth(i);
119 if (i < invokerType.parameterCount())
120 localTypes[i] = basicType(invokerType.parameterType(i));
121 }
122 }
123
124 /** For generating customized code for a single LambdaForm. */
125 private InvokerBytecodeGenerator(String className, LambdaForm form, MethodType invokerType) {
126 this(form, form.names.length,
127 className, form.debugName, invokerType);
128 // Create an array to map name indexes to locals indexes.
129 Name[] names = form.names;
130 for (int i = 0, index = 0; i < localsMap.length; i++) {
131 localsMap[i] = index;
132 if (i < names.length) {
133 BasicType type = names[i].type();
134 index += type.basicTypeSlots();
135 localTypes[i] = type;
136 }
137 }
138 }
139
140
141 /** instance counters for dumped classes */
142 private final static HashMap<String,Integer> DUMP_CLASS_FILES_COUNTERS;
143 /** debugging flag for saving generated class files */
144 private final static File DUMP_CLASS_FILES_DIR;
145
146 static {
147 if (DUMP_CLASS_FILES) {
148 DUMP_CLASS_FILES_COUNTERS = new HashMap<>();
149 try {
150 File dumpDir = new File("DUMP_CLASS_FILES");
151 if (!dumpDir.exists()) {
152 dumpDir.mkdirs();
153 }
154 DUMP_CLASS_FILES_DIR = dumpDir;
155 System.out.println("Dumping class files to "+DUMP_CLASS_FILES_DIR+"/...");
156 } catch (Exception e) {
157 throw newInternalError(e);
158 }
159 } else {
160 DUMP_CLASS_FILES_COUNTERS = null;
161 DUMP_CLASS_FILES_DIR = null;
162 }
163 }
164
165 static void maybeDump(final String className, final byte[] classFile) {
166 if (DUMP_CLASS_FILES) {
167 java.security.AccessController.doPrivileged(
168 new java.security.PrivilegedAction<Void>() {
169 public Void run() {
170 try {
171 String dumpName = className;
172 //dumpName = dumpName.replace('/', '-');
173 File dumpFile = new File(DUMP_CLASS_FILES_DIR, dumpName+".class");
174 System.out.println("dump: " + dumpFile);
175 dumpFile.getParentFile().mkdirs();
176 FileOutputStream file = new FileOutputStream(dumpFile);
177 file.write(classFile);
178 file.close();
179 return null;
180 } catch (IOException ex) {
181 throw newInternalError(ex);
182 }
183 }
184 });
185 }
186
187 }
188
189 private static String makeDumpableClassName(String className) {
190 Integer ctr;
191 synchronized (DUMP_CLASS_FILES_COUNTERS) {
192 ctr = DUMP_CLASS_FILES_COUNTERS.get(className);
193 if (ctr == null) ctr = 0;
194 DUMP_CLASS_FILES_COUNTERS.put(className, ctr+1);
195 }
196 String sfx = ctr.toString();
197 while (sfx.length() < 3)
198 sfx = "0"+sfx;
199 className += sfx;
200 return className;
201 }
202
203 class CpPatch {
204 final int index;
205 final String placeholder;
206 final Object value;
207 CpPatch(int index, String placeholder, Object value) {
208 this.index = index;
209 this.placeholder = placeholder;
210 this.value = value;
211 }
212 public String toString() {
213 return "CpPatch/index="+index+",placeholder="+placeholder+",value="+value;
214 }
215 }
216
217 Map<Object, CpPatch> cpPatches = new HashMap<>();
218
219 int cph = 0; // for counting constant placeholders
220
221 String constantPlaceholder(Object arg) {
222 String cpPlaceholder = "CONSTANT_PLACEHOLDER_" + cph++;
223 if (DUMP_CLASS_FILES) cpPlaceholder += " <<" + debugString(arg) + ">>"; // debugging aid
224 if (cpPatches.containsKey(cpPlaceholder)) {
225 throw new InternalError("observed CP placeholder twice: " + cpPlaceholder);
226 }
227 // insert placeholder in CP and remember the patch
228 int index = cw.newConst((Object) cpPlaceholder); // TODO check if aready in the constant pool
229 cpPatches.put(cpPlaceholder, new CpPatch(index, cpPlaceholder, arg));
230 return cpPlaceholder;
231 }
232
233 Object[] cpPatches(byte[] classFile) {
234 int size = getConstantPoolSize(classFile);
235 Object[] res = new Object[size];
236 for (CpPatch p : cpPatches.values()) {
237 if (p.index >= size)
238 throw new InternalError("in cpool["+size+"]: "+p+"\n"+Arrays.toString(Arrays.copyOf(classFile, 20)));
239 res[p.index] = p.value;
240 }
241 return res;
242 }
243
244 private static String debugString(Object arg) {
245 if (arg instanceof MethodHandle) {
246 MethodHandle mh = (MethodHandle) arg;
247 MemberName member = mh.internalMemberName();
248 if (member != null)
249 return member.toString();
250 return mh.debugString();
251 }
252 return arg.toString();
253 }
254
255 /**
256 * Extract the number of constant pool entries from a given class file.
257 *
258 * @param classFile the bytes of the class file in question.
259 * @return the number of entries in the constant pool.
260 */
261 private static int getConstantPoolSize(byte[] classFile) {
262 // The first few bytes:
263 // u4 magic;
264 // u2 minor_version;
265 // u2 major_version;
266 // u2 constant_pool_count;
267 return ((classFile[8] & 0xFF) << 8) | (classFile[9] & 0xFF);
268 }
269
270 /**
271 * Extract the MemberName of a newly-defined method.
272 */
273 private MemberName loadMethod(byte[] classFile) {
274 Class<?> invokerClass = loadAndInitializeInvokerClass(classFile, cpPatches(classFile));
275 return resolveInvokerMember(invokerClass, invokerName, invokerType);
276 }
277
278 /**
279 * Define a given class as anonymous class in the runtime system.
280 */
281 private static Class<?> loadAndInitializeInvokerClass(byte[] classBytes, Object[] patches) {
282 Class<?> invokerClass = UNSAFE.defineAnonymousClass(HOST_CLASS, classBytes, patches);
283 UNSAFE.ensureClassInitialized(invokerClass); // Make sure the class is initialized; VM might complain.
284 return invokerClass;
285 }
286
287 private static MemberName resolveInvokerMember(Class<?> invokerClass, String name, MethodType type) {
288 MemberName member = new MemberName(invokerClass, name, type, REF_invokeStatic);
289 //System.out.println("resolveInvokerMember => "+member);
290 //for (Method m : invokerClass.getDeclaredMethods()) System.out.println(" "+m);
291 try {
292 member = MEMBERNAME_FACTORY.resolveOrFail(REF_invokeStatic, member, HOST_CLASS, ReflectiveOperationException.class);
293 } catch (ReflectiveOperationException e) {
294 throw newInternalError(e);
295 }
296 //System.out.println("resolveInvokerMember => "+member);
297 return member;
298 }
299
300 /**
301 * Set up class file generation.
302 */
303 private void classFilePrologue() {
304 final int NOT_ACC_PUBLIC = 0; // not ACC_PUBLIC
305 cw = new ClassWriter(ClassWriter.COMPUTE_MAXS + ClassWriter.COMPUTE_FRAMES);
306 cw.visit(Opcodes.V1_8, NOT_ACC_PUBLIC + Opcodes.ACC_FINAL + Opcodes.ACC_SUPER, className, null, superName, null);
307 cw.visitSource(sourceFile, null);
308
309 String invokerDesc = invokerType.toMethodDescriptorString();
310 mv = cw.visitMethod(Opcodes.ACC_STATIC, invokerName, invokerDesc, null, null);
311 }
312
313 /**
314 * Tear down class file generation.
315 */
316 private void classFileEpilogue() {
317 mv.visitMaxs(0, 0);
318 mv.visitEnd();
319 }
320
321 /*
322 * Low-level emit helpers.
323 */
324 private void emitConst(Object con) {
325 if (con == null) {
326 mv.visitInsn(Opcodes.ACONST_NULL);
327 return;
328 }
329 if (con instanceof Integer) {
330 emitIconstInsn((int) con);
331 return;
332 }
333 if (con instanceof Long) {
334 long x = (long) con;
335 if (x == (short) x) {
336 emitIconstInsn((int) x);
337 mv.visitInsn(Opcodes.I2L);
338 return;
339 }
340 }
341 if (con instanceof Float) {
342 float x = (float) con;
343 if (x == (short) x) {
344 emitIconstInsn((int) x);
345 mv.visitInsn(Opcodes.I2F);
346 return;
347 }
348 }
349 if (con instanceof Double) {
350 double x = (double) con;
351 if (x == (short) x) {
352 emitIconstInsn((int) x);
353 mv.visitInsn(Opcodes.I2D);
354 return;
355 }
356 }
357 if (con instanceof Boolean) {
358 emitIconstInsn((boolean) con ? 1 : 0);
359 return;
360 }
361 // fall through:
362 mv.visitLdcInsn(con);
363 }
364
365 private void emitIconstInsn(int i) {
366 int opcode;
367 switch (i) {
368 case 0: opcode = Opcodes.ICONST_0; break;
369 case 1: opcode = Opcodes.ICONST_1; break;
370 case 2: opcode = Opcodes.ICONST_2; break;
371 case 3: opcode = Opcodes.ICONST_3; break;
372 case 4: opcode = Opcodes.ICONST_4; break;
373 case 5: opcode = Opcodes.ICONST_5; break;
374 default:
375 if (i == (byte) i) {
376 mv.visitIntInsn(Opcodes.BIPUSH, i & 0xFF);
377 } else if (i == (short) i) {
378 mv.visitIntInsn(Opcodes.SIPUSH, (char) i);
379 } else {
380 mv.visitLdcInsn(i);
381 }
382 return;
383 }
384 mv.visitInsn(opcode);
385 }
386
387 /*
388 * NOTE: These load/store methods use the localsMap to find the correct index!
389 */
390 private void emitLoadInsn(BasicType type, int index) {
391 int opcode = loadInsnOpcode(type);
392 mv.visitVarInsn(opcode, localsMap[index]);
393 }
394
395 private int loadInsnOpcode(BasicType type) throws InternalError {
396 switch (type) {
397 case I_TYPE: return Opcodes.ILOAD;
398 case J_TYPE: return Opcodes.LLOAD;
399 case F_TYPE: return Opcodes.FLOAD;
400 case D_TYPE: return Opcodes.DLOAD;
401 case L_TYPE: return Opcodes.ALOAD;
402 default:
403 throw new InternalError("unknown type: " + type);
404 }
405 }
406 private void emitAloadInsn(int index) {
407 emitLoadInsn(L_TYPE, index);
408 }
409
410 private void emitStoreInsn(BasicType type, int index) {
411 int opcode = storeInsnOpcode(type);
412 mv.visitVarInsn(opcode, localsMap[index]);
413 }
414
415 private int storeInsnOpcode(BasicType type) throws InternalError {
416 switch (type) {
417 case I_TYPE: return Opcodes.ISTORE;
418 case J_TYPE: return Opcodes.LSTORE;
419 case F_TYPE: return Opcodes.FSTORE;
420 case D_TYPE: return Opcodes.DSTORE;
421 case L_TYPE: return Opcodes.ASTORE;
422 default:
423 throw new InternalError("unknown type: " + type);
424 }
425 }
426 private void emitAstoreInsn(int index) {
427 emitStoreInsn(L_TYPE, index);
428 }
429
430 private void freeFrameLocal(int oldFrameLocal) {
431 int i = indexForFrameLocal(oldFrameLocal);
432 if (i < 0) return;
433 BasicType type = localTypes[i];
434 int newFrameLocal = makeLocalTemp(type);
435 mv.visitVarInsn(loadInsnOpcode(type), oldFrameLocal);
436 mv.visitVarInsn(storeInsnOpcode(type), newFrameLocal);
437 assert(localsMap[i] == oldFrameLocal);
438 localsMap[i] = newFrameLocal;
439 assert(indexForFrameLocal(oldFrameLocal) < 0);
440 }
441 private int indexForFrameLocal(int frameLocal) {
442 for (int i = 0; i < localsMap.length; i++) {
443 if (localsMap[i] == frameLocal && localTypes[i] != V_TYPE)
444 return i;
445 }
446 return -1;
447 }
448 private int makeLocalTemp(BasicType type) {
449 int frameLocal = localsMap[localsMap.length - 1];
450 localsMap[localsMap.length - 1] = frameLocal + type.basicTypeSlots();
451 return frameLocal;
452 }
453
454 /**
455 * Emit a boxing call.
456 *
457 * @param wrapper primitive type class to box.
458 */
459 private void emitBoxing(Wrapper wrapper) {
460 String owner = "java/lang/" + wrapper.wrapperType().getSimpleName();
461 String name = "valueOf";
462 String desc = "(" + wrapper.basicTypeChar() + ")L" + owner + ";";
463 mv.visitMethodInsn(Opcodes.INVOKESTATIC, owner, name, desc, false);
464 }
465
466 /**
467 * Emit an unboxing call (plus preceding checkcast).
468 *
469 * @param wrapper wrapper type class to unbox.
470 */
471 private void emitUnboxing(Wrapper wrapper) {
472 String owner = "java/lang/" + wrapper.wrapperType().getSimpleName();
473 String name = wrapper.primitiveSimpleName() + "Value";
474 String desc = "()" + wrapper.basicTypeChar();
475 emitReferenceCast(wrapper.wrapperType(), null);
476 mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, owner, name, desc, false);
477 }
478
479 /**
480 * Emit an implicit conversion for an argument which must be of the given pclass.
481 * This is usually a no-op, except when pclass is a subword type or a reference other than Object or an interface.
482 *
483 * @param ptype type of value present on stack
484 * @param pclass type of value required on stack
485 * @param arg compile-time representation of value on stack (Node, constant) or null if none
486 */
487 private void emitImplicitConversion(BasicType ptype, Class<?> pclass, Object arg) {
488 assert(basicType(pclass) == ptype); // boxing/unboxing handled by caller
489 if (pclass == ptype.basicTypeClass() && ptype != L_TYPE)
490 return; // nothing to do
491 switch (ptype) {
492 case L_TYPE:
493 if (VerifyType.isNullConversion(Object.class, pclass, false)) {
494 if (PROFILE_LEVEL > 0)
495 emitReferenceCast(Object.class, arg);
496 return;
497 }
498 emitReferenceCast(pclass, arg);
499 return;
500 case I_TYPE:
501 if (!VerifyType.isNullConversion(int.class, pclass, false))
502 emitPrimCast(ptype.basicTypeWrapper(), Wrapper.forPrimitiveType(pclass));
503 return;
504 }
505 throw newInternalError("bad implicit conversion: tc="+ptype+": "+pclass);
506 }
507
508 /** Update localClasses type map. Return true if the information is already present. */
509 private boolean assertStaticType(Class<?> cls, Name n) {
510 int local = n.index();
511 Class<?> aclass = localClasses[local];
512 if (aclass != null && (aclass == cls || cls.isAssignableFrom(aclass))) {
513 return true; // type info is already present
514 } else if (aclass == null || aclass.isAssignableFrom(cls)) {
515 localClasses[local] = cls; // type info can be improved
516 }
517 return false;
518 }
519
520 private void emitReferenceCast(Class<?> cls, Object arg) {
521 Name writeBack = null; // local to write back result
522 if (arg instanceof Name) {
523 Name n = (Name) arg;
524 if (assertStaticType(cls, n))
525 return; // this cast was already performed
526 if (lambdaForm.useCount(n) > 1) {
527 // This guy gets used more than once.
528 writeBack = n;
529 }
530 }
531 if (isStaticallyNameable(cls)) {
532 String sig = getInternalName(cls);
533 mv.visitTypeInsn(Opcodes.CHECKCAST, sig);
534 } else {
535 mv.visitLdcInsn(constantPlaceholder(cls));
536 mv.visitTypeInsn(Opcodes.CHECKCAST, CLS);
537 mv.visitInsn(Opcodes.SWAP);
538 mv.visitMethodInsn(Opcodes.INVOKESTATIC, MHI, "castReference", CLL_SIG, false);
539 if (Object[].class.isAssignableFrom(cls))
540 mv.visitTypeInsn(Opcodes.CHECKCAST, OBJARY);
541 else if (PROFILE_LEVEL > 0)
542 mv.visitTypeInsn(Opcodes.CHECKCAST, OBJ);
543 }
544 if (writeBack != null) {
545 mv.visitInsn(Opcodes.DUP);
546 emitAstoreInsn(writeBack.index());
547 }
548 }
549
550 /**
551 * Emits an actual return instruction conforming to the given return type.
552 */
553 private void emitReturnInsn(BasicType type) {
554 int opcode;
555 switch (type) {
556 case I_TYPE: opcode = Opcodes.IRETURN; break;
557 case J_TYPE: opcode = Opcodes.LRETURN; break;
558 case F_TYPE: opcode = Opcodes.FRETURN; break;
559 case D_TYPE: opcode = Opcodes.DRETURN; break;
560 case L_TYPE: opcode = Opcodes.ARETURN; break;
561 case V_TYPE: opcode = Opcodes.RETURN; break;
562 default:
563 throw new InternalError("unknown return type: " + type);
564 }
565 mv.visitInsn(opcode);
566 }
567
568 private static String getInternalName(Class<?> c) {
569 if (c == Object.class) return OBJ;
570 else if (c == Object[].class) return OBJARY;
571 else if (c == Class.class) return CLS;
572 else if (c == MethodHandle.class) return MH;
573 assert(VerifyAccess.isTypeVisible(c, Object.class)) : c.getName();
574 return c.getName().replace('.', '/');
575 }
576
577 /**
578 * Generate customized bytecode for a given LambdaForm.
579 */
580 static MemberName generateCustomizedCode(LambdaForm form, MethodType invokerType) {
581 InvokerBytecodeGenerator g = new InvokerBytecodeGenerator("MH", form, invokerType);
582 return g.loadMethod(g.generateCustomizedCodeBytes());
583 }
584
585 /**
586 * Generate an invoker method for the passed {@link LambdaForm}.
587 */
588 private byte[] generateCustomizedCodeBytes() {
589 classFilePrologue();
590
591 // Suppress this method in backtraces displayed to the user.
592 mv.visitAnnotation("Ljava/lang/invoke/LambdaForm$Hidden;", true);
593
594 // Mark this method as a compiled LambdaForm
595 mv.visitAnnotation("Ljava/lang/invoke/LambdaForm$Compiled;", true);
596
597 // Force inlining of this invoker method.
598 mv.visitAnnotation("Ljava/lang/invoke/ForceInline;", true);
599
600 // iterate over the form's names, generating bytecode instructions for each
601 // start iterating at the first name following the arguments
602 Name onStack = null;
603 for (int i = lambdaForm.arity; i < lambdaForm.names.length; i++) {
604 Name name = lambdaForm.names[i];
605 MemberName member = name.function.member();
606 Class<?> rtype = name.function.methodType().returnType();
607
608 emitStoreResult(onStack);
609 onStack = name; // unless otherwise modified below
610
611 if (isSelectAlternative(i)) {
612 onStack = emitSelectAlternative(name, lambdaForm.names[i + 1]);
613 i++; // skip MH.invokeBasic of the selectAlternative result
614 } else if (isGuardWithCatch(i)) {
615 onStack = emitGuardWithCatch(i);
616 i = i+2; // Jump to the end of GWC idiom
617 } else if (isNewArray(rtype, name)) {
618 emitNewArray(rtype, name);
619 } else if (isStaticallyInvocable(member)) {
620 emitStaticInvoke(name);
621 } else {
622 emitInvoke(name);
623 }
624 }
625
626 // return statement
627 emitReturn(onStack);
628
629 classFileEpilogue();
630 bogusMethod(lambdaForm);
631
632 final byte[] classFile = cw.toByteArray();
633 maybeDump(className, classFile);
634 return classFile;
635 }
636
637 /**
638 * Emit an invoke for the given name.
639 */
640 void emitInvoke(Name name) {
641 assert(!isLinkerMethodInvoke(name)); // should use the static path for these
642 if (true) {
643 // push receiver
644 MethodHandle target = name.function.resolvedHandle;
645 assert(target != null) : name.exprString();
646 mv.visitLdcInsn(constantPlaceholder(target));
647 emitReferenceCast(MethodHandle.class, target);
648 } else {
649 // load receiver
650 emitAloadInsn(0);
651 emitReferenceCast(MethodHandle.class, null);
652 mv.visitFieldInsn(Opcodes.GETFIELD, MH, "form", LF_SIG);
653 mv.visitFieldInsn(Opcodes.GETFIELD, LF, "names", LFN_SIG);
654 // TODO more to come
655 }
656
657 // push arguments
658 emitPushArguments(name);
659
660 // invocation
661 MethodType type = name.function.methodType();
662 mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, MH, "invokeBasic", type.basicType().toMethodDescriptorString(), false);
663 }
664
665 static private Class<?>[] STATICALLY_INVOCABLE_PACKAGES = {
666 // Sample classes from each package we are willing to bind to statically:
667 java.lang.Object.class,
668 java.util.Arrays.class,
669 sun.misc.Unsafe.class
670 //MethodHandle.class already covered
671 };
672
673 static boolean isStaticallyInvocable(Name name) {
674 return isStaticallyInvocable(name.function.member());
675 }
676
677 static boolean isStaticallyInvocable(MemberName member) {
678 if (member == null) return false;
679 if (member.isConstructor()) return false;
680 Class<?> cls = member.getDeclaringClass();
681 if (cls.isArray() || cls.isPrimitive())
682 return false; // FIXME
683 if (cls.isAnonymousClass() || cls.isLocalClass())
684 return false; // inner class of some sort
685 if (cls.getClassLoader() != MethodHandle.class.getClassLoader())
686 return false; // not on BCP
687 if (ReflectUtil.isVMAnonymousClass(cls)) // FIXME: switch to supported API once it is added
688 return false;
689 MethodType mtype = member.getMethodOrFieldType();
690 if (!isStaticallyNameable(mtype.returnType()))
691 return false;
692 for (Class<?> ptype : mtype.parameterArray())
693 if (!isStaticallyNameable(ptype))
694 return false;
695 if (!member.isPrivate() && VerifyAccess.isSamePackage(MethodHandle.class, cls))
696 return true; // in java.lang.invoke package
697 if (member.isPublic() && isStaticallyNameable(cls))
698 return true;
699 return false;
700 }
701
702 static boolean isStaticallyNameable(Class<?> cls) {
703 if (cls == Object.class)
704 return true;
705 while (cls.isArray())
706 cls = cls.getComponentType();
707 if (cls.isPrimitive())
708 return true; // int[].class, for example
709 if (ReflectUtil.isVMAnonymousClass(cls)) // FIXME: switch to supported API once it is added
710 return false;
711 // could use VerifyAccess.isClassAccessible but the following is a safe approximation
712 if (cls.getClassLoader() != Object.class.getClassLoader())
713 return false;
714 if (VerifyAccess.isSamePackage(MethodHandle.class, cls))
715 return true;
716 if (!Modifier.isPublic(cls.getModifiers()))
717 return false;
718 for (Class<?> pkgcls : STATICALLY_INVOCABLE_PACKAGES) {
719 if (VerifyAccess.isSamePackage(pkgcls, cls))
720 return true;
721 }
722 return false;
723 }
724
725 void emitStaticInvoke(Name name) {
726 emitStaticInvoke(name.function.member(), name);
727 }
728
729 /**
730 * Emit an invoke for the given name, using the MemberName directly.
731 */
732 void emitStaticInvoke(MemberName member, Name name) {
733 assert(member.equals(name.function.member()));
734 Class<?> defc = member.getDeclaringClass();
735 String cname = getInternalName(defc);
736 String mname = member.getName();
737 String mtype;
738 byte refKind = member.getReferenceKind();
739 if (refKind == REF_invokeSpecial) {
740 // in order to pass the verifier, we need to convert this to invokevirtual in all cases
741 assert(member.canBeStaticallyBound()) : member;
742 refKind = REF_invokeVirtual;
743 }
744
745 if (member.getDeclaringClass().isInterface() && refKind == REF_invokeVirtual) {
746 // Methods from Object declared in an interface can be resolved by JVM to invokevirtual kind.
747 // Need to convert it back to invokeinterface to pass verification and make the invocation works as expected.
748 refKind = REF_invokeInterface;
749 }
750
751 // push arguments
752 emitPushArguments(name);
753
754 // invocation
755 if (member.isMethod()) {
756 mtype = member.getMethodType().toMethodDescriptorString();
757 mv.visitMethodInsn(refKindOpcode(refKind), cname, mname, mtype,
758 member.getDeclaringClass().isInterface());
759 } else {
760 mtype = MethodType.toFieldDescriptorString(member.getFieldType());
761 mv.visitFieldInsn(refKindOpcode(refKind), cname, mname, mtype);
762 }
763 // Issue a type assertion for the result, so we can avoid casts later.
764 if (name.type == L_TYPE) {
765 Class<?> rtype = member.getInvocationType().returnType();
766 assert(!rtype.isPrimitive());
767 if (rtype != Object.class && !rtype.isInterface()) {
768 assertStaticType(rtype, name);
769 }
770 }
771 }
772
773 boolean isNewArray(Class<?> rtype, Name name) {
774 return rtype.isArray() &&
775 isStaticallyNameable(rtype) &&
776 isArrayBuilder(name.function.resolvedHandle) &&
777 name.arguments.length > 0;
778 }
779
780 void emitNewArray(Class<?> rtype, Name name) throws InternalError {
781 Class<?> arrayElementType = rtype.getComponentType();
782 emitIconstInsn(name.arguments.length);
783 int xas;
784 if (!arrayElementType.isPrimitive()) {
785 mv.visitTypeInsn(Opcodes.ANEWARRAY, getInternalName(arrayElementType));
786 xas = Opcodes.AASTORE;
787 } else {
788 int tc;
789 switch (Wrapper.forPrimitiveType(arrayElementType)) {
790 case BOOLEAN: tc = Opcodes.T_BOOLEAN; xas = Opcodes.BASTORE; break;
791 case BYTE: tc = Opcodes.T_BYTE; xas = Opcodes.BASTORE; break;
792 case CHAR: tc = Opcodes.T_CHAR; xas = Opcodes.CASTORE; break;
793 case SHORT: tc = Opcodes.T_SHORT; xas = Opcodes.SASTORE; break;
794 case INT: tc = Opcodes.T_INT; xas = Opcodes.IASTORE; break;
795 case LONG: tc = Opcodes.T_LONG; xas = Opcodes.LASTORE; break;
796 case FLOAT: tc = Opcodes.T_FLOAT; xas = Opcodes.FASTORE; break;
797 case DOUBLE: tc = Opcodes.T_DOUBLE; xas = Opcodes.DASTORE; break;
798 default: throw new InternalError(rtype.getName());
799 }
800 mv.visitIntInsn(Opcodes.NEWARRAY, tc);
801 }
802 // store arguments
803 for (int i = 0; i < name.arguments.length; i++) {
804 mv.visitInsn(Opcodes.DUP);
805 emitIconstInsn(i);
806 emitPushArgument(name, i);
807 mv.visitInsn(xas);
808 }
809 // the array is left on the stack
810 assertStaticType(rtype, name);
811 }
812 int refKindOpcode(byte refKind) {
813 switch (refKind) {
814 case REF_invokeVirtual: return Opcodes.INVOKEVIRTUAL;
815 case REF_invokeStatic: return Opcodes.INVOKESTATIC;
816 case REF_invokeSpecial: return Opcodes.INVOKESPECIAL;
817 case REF_invokeInterface: return Opcodes.INVOKEINTERFACE;
818 case REF_getField: return Opcodes.GETFIELD;
819 case REF_putField: return Opcodes.PUTFIELD;
820 case REF_getStatic: return Opcodes.GETSTATIC;
821 case REF_putStatic: return Opcodes.PUTSTATIC;
822 }
823 throw new InternalError("refKind="+refKind);
824 }
825
826 static boolean isArrayBuilder(MethodHandle fn) {
827 if (fn == null)
828 return false;
829 MethodType mtype = fn.type();
830 Class<?> rtype = mtype.returnType();
831 Class<?> arrayElementType = rtype.getComponentType();
832 if (arrayElementType == null)
833 return false;
834 List<Class<?>> ptypes = mtype.parameterList();
835 int size = ptypes.size();
836 if (!ptypes.equals(Collections.nCopies(size, arrayElementType)))
837 return false;
838 // Assume varargsArray caches pointers.
839 if (fn != ValueConversions.varargsArray(rtype, size))
840 return false;
841 return true;
842 }
843
844 /**
845 * Check if MemberName is a call to a method named {@code name} in class {@code declaredClass}.
846 */
847 private boolean memberRefersTo(MemberName member, Class<?> declaringClass, String name) {
848 return member != null &&
849 member.getDeclaringClass() == declaringClass &&
850 member.getName().equals(name);
851 }
852 private boolean nameRefersTo(Name name, Class<?> declaringClass, String methodName) {
853 return name.function != null &&
854 memberRefersTo(name.function.member(), declaringClass, methodName);
855 }
856
857 /**
858 * Check if MemberName is a call to MethodHandle.invokeBasic.
859 */
860 private boolean isInvokeBasic(Name name) {
861 if (name.function == null)
862 return false;
863 if (name.arguments.length < 1)
864 return false; // must have MH argument
865 MemberName member = name.function.member();
866 return memberRefersTo(member, MethodHandle.class, "invokeBasic") &&
867 !member.isPublic() && !member.isStatic();
868 }
869
870 /**
871 * Check if MemberName is a call to MethodHandle.linkToStatic, etc.
872 */
873 private boolean isLinkerMethodInvoke(Name name) {
874 if (name.function == null)
875 return false;
876 if (name.arguments.length < 1)
877 return false; // must have MH argument
878 MemberName member = name.function.member();
879 return member != null &&
880 member.getDeclaringClass() == MethodHandle.class &&
881 !member.isPublic() && member.isStatic() &&
882 member.getName().startsWith("linkTo");
883 }
884
885 /**
886 * Check if i-th name is a call to MethodHandleImpl.selectAlternative.
887 */
888 private boolean isSelectAlternative(int pos) {
889 // selectAlternative idiom:
890 // t_{n}:L=MethodHandleImpl.selectAlternative(...)
891 // t_{n+1}:?=MethodHandle.invokeBasic(t_{n}, ...)
892 if (pos+1 >= lambdaForm.names.length) return false;
893 Name name0 = lambdaForm.names[pos];
894 Name name1 = lambdaForm.names[pos+1];
895 return nameRefersTo(name0, MethodHandleImpl.class, "selectAlternative") &&
896 isInvokeBasic(name1) &&
897 name1.lastUseIndex(name0) == 0 && // t_{n+1}:?=MethodHandle.invokeBasic(t_{n}, ...)
898 lambdaForm.lastUseIndex(name0) == pos+1; // t_{n} is local: used only in t_{n+1}
899 }
900
901 /**
902 * Check if i-th name is a start of GuardWithCatch idiom.
903 */
904 private boolean isGuardWithCatch(int pos) {
905 // GuardWithCatch idiom:
906 // t_{n}:L=MethodHandle.invokeBasic(...)
907 // t_{n+1}:L=MethodHandleImpl.guardWithCatch(*, *, *, t_{n});
908 // t_{n+2}:?=MethodHandle.invokeBasic(t_{n+1})
909 if (pos+2 >= lambdaForm.names.length) return false;
910 Name name0 = lambdaForm.names[pos];
911 Name name1 = lambdaForm.names[pos+1];
912 Name name2 = lambdaForm.names[pos+2];
913 return nameRefersTo(name1, MethodHandleImpl.class, "guardWithCatch") &&
914 isInvokeBasic(name0) &&
915 isInvokeBasic(name2) &&
916 name1.lastUseIndex(name0) == 3 && // t_{n+1}:L=MethodHandleImpl.guardWithCatch(*, *, *, t_{n});
917 lambdaForm.lastUseIndex(name0) == pos+1 && // t_{n} is local: used only in t_{n+1}
918 name2.lastUseIndex(name1) == 1 && // t_{n+2}:?=MethodHandle.invokeBasic(t_{n+1})
919 lambdaForm.lastUseIndex(name1) == pos+2; // t_{n+1} is local: used only in t_{n+2}
920 }
921
922 /**
923 * Emit bytecode for the selectAlternative idiom.
924 *
925 * The pattern looks like (Cf. MethodHandleImpl.makeGuardWithTest):
926 * <blockquote><pre>{@code
927 * Lambda(a0:L,a1:I)=>{
928 * t2:I=foo.test(a1:I);
929 * t3:L=MethodHandleImpl.selectAlternative(t2:I,(MethodHandle(int)int),(MethodHandle(int)int));
930 * t4:I=MethodHandle.invokeBasic(t3:L,a1:I);t4:I}
931 * }</pre></blockquote>
932 */
933 private Name emitSelectAlternative(Name selectAlternativeName, Name invokeBasicName) {
934 assert isStaticallyInvocable(invokeBasicName);
935
936 Name receiver = (Name) invokeBasicName.arguments[0];
937
938 Label L_fallback = new Label();
939 Label L_done = new Label();
940
941 // load test result
942 emitPushArgument(selectAlternativeName, 0);
943
944 // if_icmpne L_fallback
945 mv.visitJumpInsn(Opcodes.IFEQ, L_fallback);
946
947 // invoke selectAlternativeName.arguments[1]
948 Class<?>[] preForkClasses = localClasses.clone();
949 emitPushArgument(selectAlternativeName, 1); // get 2nd argument of selectAlternative
950 emitAstoreInsn(receiver.index()); // store the MH in the receiver slot
951 emitStaticInvoke(invokeBasicName);
952
953 // goto L_done
954 mv.visitJumpInsn(Opcodes.GOTO, L_done);
955
956 // L_fallback:
957 mv.visitLabel(L_fallback);
958
959 // invoke selectAlternativeName.arguments[2]
960 System.arraycopy(preForkClasses, 0, localClasses, 0, preForkClasses.length);
961 emitPushArgument(selectAlternativeName, 2); // get 3rd argument of selectAlternative
962 emitAstoreInsn(receiver.index()); // store the MH in the receiver slot
963 emitStaticInvoke(invokeBasicName);
964
965 // L_done:
966 mv.visitLabel(L_done);
967 // for now do not bother to merge typestate; just reset to the dominator state
968 System.arraycopy(preForkClasses, 0, localClasses, 0, preForkClasses.length);
969
970 return invokeBasicName; // return what's on stack
971 }
972
973 /**
974 * Emit bytecode for the guardWithCatch idiom.
975 *
976 * The pattern looks like (Cf. MethodHandleImpl.makeGuardWithCatch):
977 * <blockquote><pre>{@code
978 * guardWithCatch=Lambda(a0:L,a1:L,a2:L,a3:L,a4:L,a5:L,a6:L,a7:L)=>{
979 * t8:L=MethodHandle.invokeBasic(a4:L,a6:L,a7:L);
980 * t9:L=MethodHandleImpl.guardWithCatch(a1:L,a2:L,a3:L,t8:L);
981 * t10:I=MethodHandle.invokeBasic(a5:L,t9:L);t10:I}
982 * }</pre></blockquote>
983 *
984 * It is compiled into bytecode equivalent of the following code:
985 * <blockquote><pre>{@code
986 * try {
987 * return a1.invokeBasic(a6, a7);
988 * } catch (Throwable e) {
989 * if (!a2.isInstance(e)) throw e;
990 * return a3.invokeBasic(ex, a6, a7);
991 * }}
992 */
993 private Name emitGuardWithCatch(int pos) {
994 Name args = lambdaForm.names[pos];
995 Name invoker = lambdaForm.names[pos+1];
996 Name result = lambdaForm.names[pos+2];
997
998 Label L_startBlock = new Label();
999 Label L_endBlock = new Label();
1000 Label L_handler = new Label();
1001 Label L_done = new Label();
1002
1003 Class<?> returnType = result.function.resolvedHandle.type().returnType();
1004 MethodType type = args.function.resolvedHandle.type()
1005 .dropParameterTypes(0,1)
1006 .changeReturnType(returnType);
1007
1008 mv.visitTryCatchBlock(L_startBlock, L_endBlock, L_handler, "java/lang/Throwable");
1009
1010 // Normal case
1011 mv.visitLabel(L_startBlock);
1012 // load target
1013 emitPushArgument(invoker, 0);
1014 emitPushArguments(args, 1); // skip 1st argument: method handle
1015 mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, MH, "invokeBasic", type.basicType().toMethodDescriptorString(), false);
1016 mv.visitLabel(L_endBlock);
1017 mv.visitJumpInsn(Opcodes.GOTO, L_done);
1018
1019 // Exceptional case
1020 mv.visitLabel(L_handler);
1021
1022 // Check exception's type
1023 mv.visitInsn(Opcodes.DUP);
1024 // load exception class
1025 emitPushArgument(invoker, 1);
1026 mv.visitInsn(Opcodes.SWAP);
1027 mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/Class", "isInstance", "(Ljava/lang/Object;)Z", false);
1028 Label L_rethrow = new Label();
1029 mv.visitJumpInsn(Opcodes.IFEQ, L_rethrow);
1030
1031 // Invoke catcher
1032 // load catcher
1033 emitPushArgument(invoker, 2);
1034 mv.visitInsn(Opcodes.SWAP);
1035 emitPushArguments(args, 1); // skip 1st argument: method handle
1036 MethodType catcherType = type.insertParameterTypes(0, Throwable.class);
1037 mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, MH, "invokeBasic", catcherType.basicType().toMethodDescriptorString(), false);
1038 mv.visitJumpInsn(Opcodes.GOTO, L_done);
1039
1040 mv.visitLabel(L_rethrow);
1041 mv.visitInsn(Opcodes.ATHROW);
1042
1043 mv.visitLabel(L_done);
1044
1045 return result;
1046 }
1047
1048 private void emitPushArguments(Name args) {
1049 emitPushArguments(args, 0);
1050 }
1051
1052 private void emitPushArguments(Name args, int start) {
1053 for (int i = start; i < args.arguments.length; i++) {
1054 emitPushArgument(args, i);
1055 }
1056 }
1057
1058 private void emitPushArgument(Name name, int paramIndex) {
1059 Object arg = name.arguments[paramIndex];
1060 Class<?> ptype = name.function.methodType().parameterType(paramIndex);
1061 emitPushArgument(ptype, arg);
1062 }
1063
1064 private void emitPushArgument(Class<?> ptype, Object arg) {
1065 BasicType bptype = basicType(ptype);
1066 if (arg instanceof Name) {
1067 Name n = (Name) arg;
1068 emitLoadInsn(n.type, n.index());
1069 emitImplicitConversion(n.type, ptype, n);
1070 } else if ((arg == null || arg instanceof String) && bptype == L_TYPE) {
1071 emitConst(arg);
1072 } else {
1073 if (Wrapper.isWrapperType(arg.getClass()) && bptype != L_TYPE) {
1074 emitConst(arg);
1075 } else {
1076 mv.visitLdcInsn(constantPlaceholder(arg));
1077 emitImplicitConversion(L_TYPE, ptype, arg);
1078 }
1079 }
1080 }
1081
1082 /**
1083 * Store the name to its local, if necessary.
1084 */
1085 private void emitStoreResult(Name name) {
1086 if (name != null && name.type != V_TYPE) {
1087 // non-void: actually assign
1088 emitStoreInsn(name.type, name.index());
1089 }
1090 }
1091
1092 /**
1093 * Emits a return statement from a LF invoker. If required, the result type is cast to the correct return type.
1094 */
1095 private void emitReturn(Name onStack) {
1096 // return statement
1097 Class<?> rclass = invokerType.returnType();
1098 BasicType rtype = lambdaForm.returnType();
1099 assert(rtype == basicType(rclass)); // must agree
1100 if (rtype == V_TYPE) {
1101 // void
1102 mv.visitInsn(Opcodes.RETURN);
1103 // it doesn't matter what rclass is; the JVM will discard any value
1104 } else {
1105 LambdaForm.Name rn = lambdaForm.names[lambdaForm.result];
1106
1107 // put return value on the stack if it is not already there
1108 if (rn != onStack) {
1109 emitLoadInsn(rtype, lambdaForm.result);
1110 }
1111
1112 emitImplicitConversion(rtype, rclass, rn);
1113
1114 // generate actual return statement
1115 emitReturnInsn(rtype);
1116 }
1117 }
1118
1119 /**
1120 * Emit a type conversion bytecode casting from "from" to "to".
1121 */
1122 private void emitPrimCast(Wrapper from, Wrapper to) {
1123 // Here's how.
1124 // - indicates forbidden
1125 // <-> indicates implicit
1126 // to ----> boolean byte short char int long float double
1127 // from boolean <-> - - - - - - -
1128 // byte - <-> i2s i2c <-> i2l i2f i2d
1129 // short - i2b <-> i2c <-> i2l i2f i2d
1130 // char - i2b i2s <-> <-> i2l i2f i2d
1131 // int - i2b i2s i2c <-> i2l i2f i2d
1132 // long - l2i,i2b l2i,i2s l2i,i2c l2i <-> l2f l2d
1133 // float - f2i,i2b f2i,i2s f2i,i2c f2i f2l <-> f2d
1134 // double - d2i,i2b d2i,i2s d2i,i2c d2i d2l d2f <->
1135 if (from == to) {
1136 // no cast required, should be dead code anyway
1137 return;
1138 }
1139 if (from.isSubwordOrInt()) {
1140 // cast from {byte,short,char,int} to anything
1141 emitI2X(to);
1142 } else {
1143 // cast from {long,float,double} to anything
1144 if (to.isSubwordOrInt()) {
1145 // cast to {byte,short,char,int}
1146 emitX2I(from);
1147 if (to.bitWidth() < 32) {
1148 // targets other than int require another conversion
1149 emitI2X(to);
1150 }
1151 } else {
1152 // cast to {long,float,double} - this is verbose
1153 boolean error = false;
1154 switch (from) {
1155 case LONG:
1156 switch (to) {
1157 case FLOAT: mv.visitInsn(Opcodes.L2F); break;
1158 case DOUBLE: mv.visitInsn(Opcodes.L2D); break;
1159 default: error = true; break;
1160 }
1161 break;
1162 case FLOAT:
1163 switch (to) {
1164 case LONG : mv.visitInsn(Opcodes.F2L); break;
1165 case DOUBLE: mv.visitInsn(Opcodes.F2D); break;
1166 default: error = true; break;
1167 }
1168 break;
1169 case DOUBLE:
1170 switch (to) {
1171 case LONG : mv.visitInsn(Opcodes.D2L); break;
1172 case FLOAT: mv.visitInsn(Opcodes.D2F); break;
1173 default: error = true; break;
1174 }
1175 break;
1176 default:
1177 error = true;
1178 break;
1179 }
1180 if (error) {
1181 throw new IllegalStateException("unhandled prim cast: " + from + "2" + to);
1182 }
1183 }
1184 }
1185 }
1186
1187 private void emitI2X(Wrapper type) {
1188 switch (type) {
1189 case BYTE: mv.visitInsn(Opcodes.I2B); break;
1190 case SHORT: mv.visitInsn(Opcodes.I2S); break;
1191 case CHAR: mv.visitInsn(Opcodes.I2C); break;
1192 case INT: /* naught */ break;
1193 case LONG: mv.visitInsn(Opcodes.I2L); break;
1194 case FLOAT: mv.visitInsn(Opcodes.I2F); break;
1195 case DOUBLE: mv.visitInsn(Opcodes.I2D); break;
1196 case BOOLEAN:
1197 // For compatibility with ValueConversions and explicitCastArguments:
1198 mv.visitInsn(Opcodes.ICONST_1);
1199 mv.visitInsn(Opcodes.IAND);
1200 break;
1201 default: throw new InternalError("unknown type: " + type);
1202 }
1203 }
1204
1205 private void emitX2I(Wrapper type) {
1206 switch (type) {
1207 case LONG: mv.visitInsn(Opcodes.L2I); break;
1208 case FLOAT: mv.visitInsn(Opcodes.F2I); break;
1209 case DOUBLE: mv.visitInsn(Opcodes.D2I); break;
1210 default: throw new InternalError("unknown type: " + type);
1211 }
1212 }
1213
1214 /**
1215 * Generate bytecode for a LambdaForm.vmentry which calls interpretWithArguments.
1216 */
1217 static MemberName generateLambdaFormInterpreterEntryPoint(String sig) {
1218 assert(isValidSignature(sig));
1219 String name = "interpret_"+signatureReturn(sig).basicTypeChar();
1220 MethodType type = signatureType(sig); // sig includes leading argument
1221 type = type.changeParameterType(0, MethodHandle.class);
1222 InvokerBytecodeGenerator g = new InvokerBytecodeGenerator("LFI", name, type);
1223 return g.loadMethod(g.generateLambdaFormInterpreterEntryPointBytes());
1224 }
1225
1226 private byte[] generateLambdaFormInterpreterEntryPointBytes() {
1227 classFilePrologue();
1228
1229 // Suppress this method in backtraces displayed to the user.
1230 mv.visitAnnotation("Ljava/lang/invoke/LambdaForm$Hidden;", true);
1231
1232 // Don't inline the interpreter entry.
1233 mv.visitAnnotation("Ljava/lang/invoke/DontInline;", true);
1234
1235 // create parameter array
1236 emitIconstInsn(invokerType.parameterCount());
1237 mv.visitTypeInsn(Opcodes.ANEWARRAY, "java/lang/Object");
1238
1239 // fill parameter array
1240 for (int i = 0; i < invokerType.parameterCount(); i++) {
1241 Class<?> ptype = invokerType.parameterType(i);
1242 mv.visitInsn(Opcodes.DUP);
1243 emitIconstInsn(i);
1244 emitLoadInsn(basicType(ptype), i);
1245 // box if primitive type
1246 if (ptype.isPrimitive()) {
1247 emitBoxing(Wrapper.forPrimitiveType(ptype));
1248 }
1249 mv.visitInsn(Opcodes.AASTORE);
1250 }
1251 // invoke
1252 emitAloadInsn(0);
1253 mv.visitFieldInsn(Opcodes.GETFIELD, MH, "form", "Ljava/lang/invoke/LambdaForm;");
1254 mv.visitInsn(Opcodes.SWAP); // swap form and array; avoid local variable
1255 mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, LF, "interpretWithArguments", "([Ljava/lang/Object;)Ljava/lang/Object;", false);
1256
1257 // maybe unbox
1258 Class<?> rtype = invokerType.returnType();
1259 if (rtype.isPrimitive() && rtype != void.class) {
1260 emitUnboxing(Wrapper.forPrimitiveType(rtype));
1261 }
1262
1263 // return statement
1264 emitReturnInsn(basicType(rtype));
1265
1266 classFileEpilogue();
1267 bogusMethod(invokerType);
1268
1269 final byte[] classFile = cw.toByteArray();
1270 maybeDump(className, classFile);
1271 return classFile;
1272 }
1273
1274 /**
1275 * Generate bytecode for a NamedFunction invoker.
1276 */
1277 static MemberName generateNamedFunctionInvoker(MethodTypeForm typeForm) {
1278 MethodType invokerType = NamedFunction.INVOKER_METHOD_TYPE;
1279 String invokerName = "invoke_" + shortenSignature(basicTypeSignature(typeForm.erasedType()));
1280 InvokerBytecodeGenerator g = new InvokerBytecodeGenerator("NFI", invokerName, invokerType);
1281 return g.loadMethod(g.generateNamedFunctionInvokerImpl(typeForm));
1282 }
1283
1284 private byte[] generateNamedFunctionInvokerImpl(MethodTypeForm typeForm) {
1285 MethodType dstType = typeForm.erasedType();
1286 classFilePrologue();
1287
1288 // Suppress this method in backtraces displayed to the user.
1289 mv.visitAnnotation("Ljava/lang/invoke/LambdaForm$Hidden;", true);
1290
1291 // Force inlining of this invoker method.
1292 mv.visitAnnotation("Ljava/lang/invoke/ForceInline;", true);
1293
1294 // Load receiver
1295 emitAloadInsn(0);
1296
1297 // Load arguments from array
1298 for (int i = 0; i < dstType.parameterCount(); i++) {
1299 emitAloadInsn(1);
1300 emitIconstInsn(i);
1301 mv.visitInsn(Opcodes.AALOAD);
1302
1303 // Maybe unbox
1304 Class<?> dptype = dstType.parameterType(i);
1305 if (dptype.isPrimitive()) {
1306 Class<?> sptype = dstType.basicType().wrap().parameterType(i);
1307 Wrapper dstWrapper = Wrapper.forBasicType(dptype);
1308 Wrapper srcWrapper = dstWrapper.isSubwordOrInt() ? Wrapper.INT : dstWrapper; // narrow subword from int
1309 emitUnboxing(srcWrapper);
1310 emitPrimCast(srcWrapper, dstWrapper);
1311 }
1312 }
1313
1314 // Invoke
1315 String targetDesc = dstType.basicType().toMethodDescriptorString();
1316 mv.visitMethodInsn(Opcodes.INVOKEVIRTUAL, MH, "invokeBasic", targetDesc, false);
1317
1318 // Box primitive types
1319 Class<?> rtype = dstType.returnType();
1320 if (rtype != void.class && rtype.isPrimitive()) {
1321 Wrapper srcWrapper = Wrapper.forBasicType(rtype);
1322 Wrapper dstWrapper = srcWrapper.isSubwordOrInt() ? Wrapper.INT : srcWrapper; // widen subword to int
1323 // boolean casts not allowed
1324 emitPrimCast(srcWrapper, dstWrapper);
1325 emitBoxing(dstWrapper);
1326 }
1327
1328 // If the return type is void we return a null reference.
1329 if (rtype == void.class) {
1330 mv.visitInsn(Opcodes.ACONST_NULL);
1331 }
1332 emitReturnInsn(L_TYPE); // NOTE: NamedFunction invokers always return a reference value.
1333
1334 classFileEpilogue();
1335 bogusMethod(dstType);
1336
1337 final byte[] classFile = cw.toByteArray();
1338 maybeDump(className, classFile);
1339 return classFile;
1340 }
1341
1342 /**
1343 * Emit a bogus method that just loads some string constants. This is to get the constants into the constant pool
1344 * for debugging purposes.
1345 */
1346 private void bogusMethod(Object... os) {
1347 if (DUMP_CLASS_FILES) {
1348 mv = cw.visitMethod(Opcodes.ACC_STATIC, "dummy", "()V", null, null);
1349 for (Object o : os) {
1350 mv.visitLdcInsn(o.toString());
1351 mv.visitInsn(Opcodes.POP);
1352 }
1353 mv.visitInsn(Opcodes.RETURN);
1354 mv.visitMaxs(0, 0);
1355 mv.visitEnd();
1356 }
1357 }
1358 }