2 * Copyright (C) 2008 The Android Open Source Project
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
18 * Stacks and their uses (e.g. native --> interpreted method calls).
20 * See the majestic ASCII art in Stack.h.
29 * Initialize the interpreter stack in a new thread.
31 * Currently this doesn't do much, since we don't need to zero out the
32 * stack (and we really don't want to if it was created with mmap).
34 bool dvmInitInterpStack(Thread* thread, int stackSize)
36 assert(thread->interpStackStart != NULL);
38 assert(thread->curFrame == NULL);
44 * We're calling an interpreted method from an internal VM function or
47 * Push a frame for an interpreted method onto the stack. This is only
48 * used when calling into interpreted code from native code. (The
49 * interpreter does its own stack frame manipulation for interp-->interp
52 * The size we need to reserve is the sum of parameters, local variables,
53 * saved goodies, and outbound parameters.
55 * We start by inserting a "break" frame, which ensures that the interpreter
56 * hands control back to us after the function we call returns or an
57 * uncaught exception is thrown.
59 static bool dvmPushInterpFrame(Thread* self, const Method* method)
61 StackSaveArea* saveBlock;
62 StackSaveArea* breakSaveBlock;
66 assert(!dvmIsNativeMethod(method));
67 assert(!dvmIsAbstractMethod(method));
69 stackReq = method->registersSize * 4 // params + locals
70 + sizeof(StackSaveArea) * 2 // break frame + regular frame
71 + method->outsSize * 4; // args to other methods
73 if (self->curFrame != NULL)
74 stackPtr = (u1*) SAVEAREA_FROM_FP(self->curFrame);
76 stackPtr = self->interpStackStart;
78 if (stackPtr - stackReq < self->interpStackEnd) {
79 /* not enough space */
80 LOGW("Stack overflow on call to interp "
81 "(req=%d top=%p cur=%p size=%d %s.%s)\n",
82 stackReq, self->interpStackStart, self->curFrame,
83 self->interpStackSize, method->clazz->descriptor, method->name);
84 dvmHandleStackOverflow(self, method);
85 assert(dvmCheckException(self));
90 * Shift the stack pointer down, leaving space for the function's
91 * args/registers and save area.
93 stackPtr -= sizeof(StackSaveArea);
94 breakSaveBlock = (StackSaveArea*)stackPtr;
95 stackPtr -= method->registersSize * 4 + sizeof(StackSaveArea);
96 saveBlock = (StackSaveArea*) stackPtr;
98 #if !defined(NDEBUG) && !defined(PAD_SAVE_AREA)
99 /* debug -- memset the new stack, unless we want valgrind's help */
100 memset(stackPtr - (method->outsSize*4), 0xaf, stackReq);
103 breakSaveBlock->prevSave = FP_FROM_SAVEAREA(self->curFrame);
104 saveBlock->prevSave = breakSaveBlock;
107 breakSaveBlock->prevFrame = self->curFrame;
108 breakSaveBlock->savedPc = NULL; // not required
109 breakSaveBlock->xtra.localRefCookie = 0; // not required
110 breakSaveBlock->method = NULL;
111 saveBlock->prevFrame = FP_FROM_SAVEAREA(breakSaveBlock);
112 saveBlock->savedPc = NULL; // not required
113 saveBlock->xtra.currentPc = NULL; // not required?
114 saveBlock->method = method;
116 LOGVV("PUSH frame: old=%p new=%p (size=%d)\n",
117 self->curFrame, FP_FROM_SAVEAREA(saveBlock),
118 (u1*)self->curFrame - (u1*)FP_FROM_SAVEAREA(saveBlock));
120 self->curFrame = FP_FROM_SAVEAREA(saveBlock);
126 * We're calling a JNI native method from an internal VM fuction or
127 * via reflection. This is also used to create the "fake" native-method
128 * frames at the top of the interpreted stack.
130 * This actually pushes two frames; the first is a "break" frame.
132 * The top frame has additional space for JNI local reference tracking.
134 bool dvmPushJNIFrame(Thread* self, const Method* method)
136 StackSaveArea* saveBlock;
137 StackSaveArea* breakSaveBlock;
141 assert(dvmIsNativeMethod(method));
143 stackReq = method->registersSize * 4 // params only
144 + sizeof(StackSaveArea) * 2; // break frame + regular frame
146 if (self->curFrame != NULL)
147 stackPtr = (u1*) SAVEAREA_FROM_FP(self->curFrame);
149 stackPtr = self->interpStackStart;
151 if (stackPtr - stackReq < self->interpStackEnd) {
152 /* not enough space */
153 LOGW("Stack overflow on call to native "
154 "(req=%d top=%p cur=%p size=%d '%s')\n",
155 stackReq, self->interpStackStart, self->curFrame,
156 self->interpStackSize, method->name);
157 dvmHandleStackOverflow(self, method);
158 assert(dvmCheckException(self));
163 * Shift the stack pointer down, leaving space for just the stack save
164 * area for the break frame, then shift down farther for the full frame.
165 * We leave space for the method args, which are copied in later.
167 stackPtr -= sizeof(StackSaveArea);
168 breakSaveBlock = (StackSaveArea*)stackPtr;
169 stackPtr -= method->registersSize * 4 + sizeof(StackSaveArea);
170 saveBlock = (StackSaveArea*) stackPtr;
172 #if !defined(NDEBUG) && !defined(PAD_SAVE_AREA)
173 /* debug -- memset the new stack */
174 memset(stackPtr, 0xaf, stackReq);
177 if (self->curFrame == NULL)
178 breakSaveBlock->prevSave = NULL;
180 breakSaveBlock->prevSave = FP_FROM_SAVEAREA(self->curFrame);
181 saveBlock->prevSave = breakSaveBlock;
184 breakSaveBlock->prevFrame = self->curFrame;
185 breakSaveBlock->savedPc = NULL; // not required
186 breakSaveBlock->xtra.localRefCookie = 0; // not required
187 breakSaveBlock->method = NULL;
188 saveBlock->prevFrame = FP_FROM_SAVEAREA(breakSaveBlock);
189 saveBlock->savedPc = NULL; // not required
190 #ifdef USE_INDIRECT_REF
191 saveBlock->xtra.localRefCookie = self->jniLocalRefTable.segmentState.all;
193 saveBlock->xtra.localRefCookie = self->jniLocalRefTable.nextEntry;
195 saveBlock->method = method;
197 LOGVV("PUSH JNI frame: old=%p new=%p (size=%d)\n",
198 self->curFrame, FP_FROM_SAVEAREA(saveBlock),
199 (u1*)self->curFrame - (u1*)FP_FROM_SAVEAREA(saveBlock));
201 self->curFrame = FP_FROM_SAVEAREA(saveBlock);
207 * This is used by the JNI PushLocalFrame call. We push a new frame onto
208 * the stack that has no ins, outs, or locals, and no break frame above it.
209 * It's strictly used for tracking JNI local refs, and will be popped off
210 * by dvmPopFrame if it's not removed explicitly.
212 bool dvmPushLocalFrame(Thread* self, const Method* method)
214 StackSaveArea* saveBlock;
218 assert(dvmIsNativeMethod(method));
220 stackReq = sizeof(StackSaveArea); // regular frame
222 assert(self->curFrame != NULL);
223 stackPtr = (u1*) SAVEAREA_FROM_FP(self->curFrame);
225 if (stackPtr - stackReq < self->interpStackEnd) {
226 /* not enough space; let JNI throw the exception */
227 LOGW("Stack overflow on PushLocal "
228 "(req=%d top=%p cur=%p size=%d '%s')\n",
229 stackReq, self->interpStackStart, self->curFrame,
230 self->interpStackSize, method->name);
231 dvmHandleStackOverflow(self, method);
232 assert(dvmCheckException(self));
237 * Shift the stack pointer down, leaving space for just the stack save
238 * area for the break frame, then shift down farther for the full frame.
240 stackPtr -= sizeof(StackSaveArea);
241 saveBlock = (StackSaveArea*) stackPtr;
243 #if !defined(NDEBUG) && !defined(PAD_SAVE_AREA)
244 /* debug -- memset the new stack */
245 memset(stackPtr, 0xaf, stackReq);
248 saveBlock->prevSave = FP_FROM_SAVEAREA(self->curFrame);
251 saveBlock->prevFrame = self->curFrame;
252 saveBlock->savedPc = NULL; // not required
253 #ifdef USE_INDIRECT_REF
254 saveBlock->xtra.localRefCookie = self->jniLocalRefTable.segmentState.all;
256 saveBlock->xtra.localRefCookie = self->jniLocalRefTable.nextEntry;
258 saveBlock->method = method;
260 LOGVV("PUSH JNI local frame: old=%p new=%p (size=%d)\n",
261 self->curFrame, FP_FROM_SAVEAREA(saveBlock),
262 (u1*)self->curFrame - (u1*)FP_FROM_SAVEAREA(saveBlock));
264 self->curFrame = FP_FROM_SAVEAREA(saveBlock);
270 * Pop one frame pushed on by JNI PushLocalFrame.
272 * If we've gone too far, the previous frame is either a break frame or
273 * an interpreted frame. Either way, the method pointer won't match.
275 bool dvmPopLocalFrame(Thread* self)
277 StackSaveArea* saveBlock = SAVEAREA_FROM_FP(self->curFrame);
279 assert(!dvmIsBreakFrame(self->curFrame));
280 if (saveBlock->method != SAVEAREA_FROM_FP(saveBlock->prevFrame)->method) {
282 * The previous frame doesn't have the same method pointer -- we've
283 * been asked to pop too much.
285 assert(dvmIsBreakFrame(saveBlock->prevFrame) ||
287 SAVEAREA_FROM_FP(saveBlock->prevFrame)->method));
291 LOGVV("POP JNI local frame: removing %s, now %s\n",
292 saveBlock->method->name,
293 SAVEAREA_FROM_FP(saveBlock->prevFrame)->method->name);
294 dvmPopJniLocals(self, saveBlock);
295 self->curFrame = saveBlock->prevFrame;
301 * Pop a frame we added. There should be one method frame and one break
304 * If JNI Push/PopLocalFrame calls were mismatched, we might end up
305 * popping multiple method frames before we find the break.
307 * Returns "false" if there was no frame to pop.
309 static bool dvmPopFrame(Thread* self)
311 StackSaveArea* saveBlock;
313 if (self->curFrame == NULL)
316 saveBlock = SAVEAREA_FROM_FP(self->curFrame);
317 assert(!dvmIsBreakFrame(self->curFrame));
320 * Remove everything up to the break frame. If this was a call into
321 * native code, pop the JNI local references table.
323 while (saveBlock->prevFrame != NULL && saveBlock->method != NULL) {
324 /* probably a native->native JNI call */
326 if (dvmIsNativeMethod(saveBlock->method)) {
327 LOGVV("Popping JNI stack frame for %s.%s%s\n",
328 saveBlock->method->clazz->descriptor,
329 saveBlock->method->name,
330 (SAVEAREA_FROM_FP(saveBlock->prevFrame)->method == NULL) ?
331 "" : " (JNI local)");
332 assert(saveBlock->xtra.localRefCookie != 0);
333 //assert(saveBlock->xtra.localRefCookie >= self->jniLocalRefTable.table &&
334 // saveBlock->xtra.localRefCookie <=self->jniLocalRefTable.nextEntry);
336 dvmPopJniLocals(self, saveBlock);
339 saveBlock = SAVEAREA_FROM_FP(saveBlock->prevFrame);
341 if (saveBlock->method != NULL) {
342 LOGE("PopFrame missed the break\n");
344 dvmAbort(); // stack trashed -- nowhere to go in this thread
347 LOGVV("POP frame: cur=%p new=%p\n",
348 self->curFrame, saveBlock->prevFrame);
350 self->curFrame = saveBlock->prevFrame;
355 * Common code for dvmCallMethodV/A and dvmInvokeMethod.
357 * Pushes a call frame on, advancing self->curFrame.
359 static ClassObject* callPrep(Thread* self, const Method* method, Object* obj,
365 if (self->status != THREAD_RUNNING) {
366 LOGW("threadid=%d: status=%d on call to %s.%s -\n",
367 self->threadId, self->status,
368 method->clazz->descriptor, method->name);
372 assert(self != NULL);
373 assert(method != NULL);
378 clazz = method->clazz;
381 char* desc = dexProtoCopyMethodDescriptor(&method->prototype);
382 LOGVV("thread=%d native code calling %s.%s %s\n", self->threadId,
383 clazz->descriptor, method->name, desc);
388 /* needed for java.lang.reflect.Method.invoke */
389 if (!dvmCheckMethodAccess(dvmGetCaller2Class(self->curFrame),
392 /* note this throws IAException, not IAError */
393 dvmThrowException("Ljava/lang/IllegalAccessException;",
394 "access to method denied");
400 * Push a call frame on. If there isn't enough room for ins, locals,
401 * outs, and the saved state, it will throw an exception.
403 * This updates self->curFrame.
405 if (dvmIsNativeMethod(method)) {
406 /* native code calling native code the hard way */
407 if (!dvmPushJNIFrame(self, method)) {
408 assert(dvmCheckException(self));
412 /* native code calling interpreted code */
413 if (!dvmPushInterpFrame(self, method)) {
414 assert(dvmCheckException(self));
423 * Issue a method call.
425 * Pass in NULL for "obj" on calls to static methods.
427 * (Note this can't be inlined because it takes a variable number of args.)
429 void dvmCallMethod(Thread* self, const Method* method, Object* obj,
430 JValue* pResult, ...)
433 va_start(args, pResult);
434 dvmCallMethodV(self, method, obj, false, pResult, args);
439 * Issue a method call with a variable number of arguments. We process
440 * the contents of "args" by scanning the method signature.
442 * Pass in NULL for "obj" on calls to static methods.
444 * We don't need to take the class as an argument because, in Dalvik,
445 * we don't need to worry about static synchronized methods.
447 void dvmCallMethodV(Thread* self, const Method* method, Object* obj,
448 bool fromJni, JValue* pResult, va_list args)
450 const char* desc = &(method->shorty[1]); // [0] is the return type.
455 clazz = callPrep(self, method, obj, false);
459 /* "ins" for new frame start at frame pointer plus locals */
460 ins = ((u4*)self->curFrame) + (method->registersSize - method->insSize);
462 //LOGD(" FP is %p, INs live at >= %p\n", self->curFrame, ins);
464 /* put "this" pointer into in0 if appropriate */
465 if (!dvmIsStaticMethod(method)) {
466 #ifdef WITH_EXTRA_OBJECT_VALIDATION
467 assert(obj != NULL && dvmIsValidObject(obj));
473 JNIEnv* env = self->jniEnv;
474 while (*desc != '\0') {
476 case 'D': case 'J': {
477 u8 val = va_arg(args, u8);
478 memcpy(ins, &val, 8); // EABI prevents direct store
484 /* floats were normalized to doubles; convert back */
485 float f = (float) va_arg(args, double);
486 *ins++ = dvmFloatToU4(f);
490 case 'L': { /* 'shorty' descr uses L for all refs, incl array */
491 void* argObj = va_arg(args, void*);
492 assert(obj == NULL || dvmIsValidObject(obj));
494 *ins++ = (u4) dvmDecodeIndirectRef(env, argObj);
496 *ins++ = (u4) argObj;
501 /* Z B C S I -- all passed as 32-bit integers */
502 *ins++ = va_arg(args, u4);
510 if (verifyCount != method->insSize) {
511 LOGE("Got vfycount=%d insSize=%d for %s.%s\n", verifyCount,
512 method->insSize, clazz->descriptor, method->name);
518 //dvmDumpThreadStack(dvmThreadSelf());
520 if (dvmIsNativeMethod(method)) {
521 TRACE_METHOD_ENTER(self, method);
523 * Because we leave no space for local variables, "curFrame" points
524 * directly at the method arguments.
526 (*method->nativeFunc)(self->curFrame, pResult, method, self);
527 TRACE_METHOD_EXIT(self, method);
529 dvmInterpret(self, method, pResult);
539 * Issue a method call with arguments provided in an array. We process
540 * the contents of "args" by scanning the method signature.
542 * The values were likely placed into an uninitialized jvalue array using
543 * the field specifiers, which means that sub-32-bit fields (e.g. short,
544 * boolean) may not have 32 or 64 bits of valid data. This is different
545 * from the varargs invocation where the C compiler does a widening
546 * conversion when calling a function. As a result, we have to be a
547 * little more precise when pulling stuff out.
549 * "args" may be NULL if the method has no arguments.
551 void dvmCallMethodA(Thread* self, const Method* method, Object* obj,
552 bool fromJni, JValue* pResult, const jvalue* args)
554 const char* desc = &(method->shorty[1]); // [0] is the return type.
559 clazz = callPrep(self, method, obj, false);
563 /* "ins" for new frame start at frame pointer plus locals */
564 ins = ((u4*)self->curFrame) + (method->registersSize - method->insSize);
566 /* put "this" pointer into in0 if appropriate */
567 if (!dvmIsStaticMethod(method)) {
569 *ins++ = (u4) obj; /* obj is a "real" ref */
573 JNIEnv* env = self->jniEnv;
574 while (*desc != '\0') {
576 case 'D': /* 64-bit quantity; have to use */
577 case 'J': /* memcpy() in case of mis-alignment */
578 memcpy(ins, &args->j, 8);
580 verifyCount++; /* this needs an extra push */
582 case 'L': /* includes array refs */
584 *ins++ = (u4) dvmDecodeIndirectRef(env, args->l);
586 *ins++ = (u4) args->l;
590 *ins++ = args->i; /* full 32 bits */
593 *ins++ = args->s; /* 16 bits, sign-extended */
596 *ins++ = args->c; /* 16 bits, unsigned */
599 *ins++ = args->b; /* 8 bits, sign-extended */
602 *ins++ = args->z; /* 8 bits, zero or non-zero */
605 LOGE("Invalid char %c in short signature of %s.%s\n",
606 *(desc-1), clazz->descriptor, method->name);
616 if (verifyCount != method->insSize) {
617 LOGE("Got vfycount=%d insSize=%d for %s.%s\n", verifyCount,
618 method->insSize, clazz->descriptor, method->name);
624 if (dvmIsNativeMethod(method)) {
625 TRACE_METHOD_ENTER(self, method);
627 * Because we leave no space for local variables, "curFrame" points
628 * directly at the method arguments.
630 (*method->nativeFunc)(self->curFrame, pResult, method, self);
631 TRACE_METHOD_EXIT(self, method);
633 dvmInterpret(self, method, pResult);
641 * Invoke a method, using the specified arguments and return type, through
642 * one of the reflection interfaces. Could be a virtual or direct method
643 * (including constructors). Used for reflection.
645 * Deals with boxing/unboxing primitives and performs widening conversions.
647 * "invokeObj" will be null for a static method.
649 * If the invocation returns with an exception raised, we have to wrap it.
651 Object* dvmInvokeMethod(Object* obj, const Method* method,
652 ArrayObject* argList, ArrayObject* params, ClassObject* returnType,
656 Object* retObj = NULL;
657 Thread* self = dvmThreadSelf();
659 int verifyCount, argListLength;
662 /* verify arg count */
664 argListLength = argList->length;
667 if (argListLength != (int) params->length) {
668 LOGI("invoke: expected %d args, received %d args\n",
669 params->length, argListLength);
670 dvmThrowException("Ljava/lang/IllegalArgumentException;",
671 "wrong number of arguments");
675 clazz = callPrep(self, method, obj, !noAccessCheck);
679 /* "ins" for new frame start at frame pointer plus locals */
680 ins = ((s4*)self->curFrame) + (method->registersSize - method->insSize);
683 //LOGD(" FP is %p, INs live at >= %p\n", self->curFrame, ins);
685 /* put "this" pointer into in0 if appropriate */
686 if (!dvmIsStaticMethod(method)) {
693 * Copy the args onto the stack. Primitive types are converted when
694 * necessary, and object types are verified.
700 args = (DataObject**) argList->contents;
701 types = (ClassObject**) params->contents;
702 for (i = 0; i < argListLength; i++) {
705 width = dvmConvertArgument(*args++, *types++, ins);
707 if (*(args-1) != NULL) {
708 LOGV("invoke: type mismatch on arg %d ('%s' '%s')\n",
709 i, (*(args-1))->obj.clazz->descriptor,
710 (*(types-1))->descriptor);
712 dvmPopFrame(self); // throw wants to pull PC out of stack
713 dvmThrowException("Ljava/lang/IllegalArgumentException;",
714 "argument type mismatch");
719 verifyCount += width;
722 if (verifyCount != method->insSize) {
723 LOGE("Got vfycount=%d insSize=%d for %s.%s\n", verifyCount,
724 method->insSize, clazz->descriptor, method->name);
728 //dvmDumpThreadStack(dvmThreadSelf());
730 if (dvmIsNativeMethod(method)) {
731 TRACE_METHOD_ENTER(self, method);
733 * Because we leave no space for local variables, "curFrame" points
734 * directly at the method arguments.
736 (*method->nativeFunc)(self->curFrame, &retval, method, self);
737 TRACE_METHOD_EXIT(self, method);
739 dvmInterpret(self, method, &retval);
743 * If an exception is raised, wrap and replace. This is necessary
744 * because the invoked method could have thrown a checked exception
745 * that the caller wasn't prepared for.
747 * We might be able to do this up in the interpreted code, but that will
748 * leave us with a shortened stack trace in the top-level exception.
750 if (dvmCheckException(self)) {
751 dvmWrapException("Ljava/lang/reflect/InvocationTargetException;");
754 * If this isn't a void method or constructor, convert the return type
755 * to an appropriate object.
757 * We don't do this when an exception is raised because the value
758 * in "retval" is undefined.
760 if (returnType != NULL) {
761 retObj = (Object*)dvmWrapPrimitive(retval, returnType);
762 dvmReleaseTrackedAlloc(retObj, NULL);
772 typedef struct LineNumFromPcContext {
775 } LineNumFromPcContext;
777 static int lineNumForPcCb(void *cnxt, u4 address, u4 lineNum)
779 LineNumFromPcContext *pContext = (LineNumFromPcContext *)cnxt;
781 // We know that this callback will be called in
782 // ascending address order, so keep going until we find
783 // a match or we've just gone past it.
785 if (address > pContext->address) {
786 // The line number from the previous positions callback
787 // wil be the final result.
791 pContext->lineNum = lineNum;
793 return (address == pContext->address) ? 1 : 0;
797 * Determine the source file line number based on the program counter.
798 * "pc" is an offset, in 16-bit units, from the start of the method's code.
800 * Returns -1 if no match was found (possibly because the source files were
801 * compiled without "-g", so no line number information is present).
802 * Returns -2 for native methods (as expected in exception traces).
804 int dvmLineNumFromPC(const Method* method, u4 relPc)
806 const DexCode* pDexCode = dvmGetMethodCode(method);
808 if (pDexCode == NULL) {
809 if (dvmIsNativeMethod(method) && !dvmIsAbstractMethod(method))
811 return -1; /* can happen for abstract method stub */
814 LineNumFromPcContext context;
815 memset(&context, 0, sizeof(context));
816 context.address = relPc;
817 // A method with no line number info should return -1
818 context.lineNum = -1;
820 dexDecodeDebugInfo(method->clazz->pDvmDex->pDexFile, pDexCode,
821 method->clazz->descriptor,
822 method->prototype.protoIdx,
824 lineNumForPcCb, NULL, &context);
826 return context.lineNum;
830 * Compute the frame depth.
832 * Excludes "break" frames.
834 int dvmComputeExactFrameDepth(const void* fp)
838 for ( ; fp != NULL; fp = SAVEAREA_FROM_FP(fp)->prevFrame) {
839 if (!dvmIsBreakFrame(fp))
847 * Compute the "vague" frame depth, which is just a pointer subtraction.
848 * The result is NOT an overly generous assessment of the number of
849 * frames; the only meaningful use is to compare against the result of
850 * an earlier invocation.
852 * Useful for implementing single-step debugger modes, which may need to
853 * call this for every instruction.
855 int dvmComputeVagueFrameDepth(Thread* thread, const void* fp)
857 const u1* interpStackStart = thread->interpStackStart;
859 assert((u1*) fp >= interpStackStart - thread->interpStackSize);
860 assert((u1*) fp < interpStackStart);
861 return interpStackStart - (u1*) fp;
865 * Get the calling frame. Pass in the current fp.
867 * Skip "break" frames and reflection invoke frames.
869 void* dvmGetCallerFP(const void* curFrame)
871 void* caller = SAVEAREA_FROM_FP(curFrame)->prevFrame;
872 StackSaveArea* saveArea;
875 if (dvmIsBreakFrame(caller)) {
876 /* pop up one more */
877 caller = SAVEAREA_FROM_FP(caller)->prevFrame;
879 return NULL; /* hit the top */
882 * If we got here by java.lang.reflect.Method.invoke(), we don't
883 * want to return Method's class loader. Shift up one and try
886 saveArea = SAVEAREA_FROM_FP(caller);
887 if (dvmIsReflectionMethod(saveArea->method)) {
888 caller = saveArea->prevFrame;
889 assert(caller != NULL);
898 * Get the caller's class. Pass in the current fp.
900 * This is used by e.g. java.lang.Class.
902 ClassObject* dvmGetCallerClass(const void* curFrame)
906 caller = dvmGetCallerFP(curFrame);
910 return SAVEAREA_FROM_FP(caller)->method->clazz;
914 * Get the caller's caller's class. Pass in the current fp.
916 * This is used by e.g. java.lang.Class, which wants to know about the
917 * class loader of the method that called it.
919 ClassObject* dvmGetCaller2Class(const void* curFrame)
921 void* caller = SAVEAREA_FROM_FP(curFrame)->prevFrame;
925 if (dvmIsBreakFrame(caller) && SAVEAREA_FROM_FP(caller)->prevFrame == NULL)
929 callerCaller = dvmGetCallerFP(caller);
930 if (callerCaller == NULL)
933 return SAVEAREA_FROM_FP(callerCaller)->method->clazz;
937 * Get the caller's caller's caller's class. Pass in the current fp.
939 * This is used by e.g. java.lang.Class, which wants to know about the
940 * class loader of the method that called it.
942 ClassObject* dvmGetCaller3Class(const void* curFrame)
944 void* caller = SAVEAREA_FROM_FP(curFrame)->prevFrame;
948 if (dvmIsBreakFrame(caller) && SAVEAREA_FROM_FP(caller)->prevFrame == NULL)
951 /* Walk up two frames if possible. */
952 for (i = 0; i < 2; i++) {
953 caller = dvmGetCallerFP(caller);
958 return SAVEAREA_FROM_FP(caller)->method->clazz;
962 * Create a flat array of methods that comprise the current interpreter
963 * stack trace. Pass in the current frame ptr.
965 * Allocates a new array and fills it with method pointers. Break frames
966 * are skipped, but reflection invocations are not. The caller must free
969 * The current frame will be in element 0.
971 * Returns "true" on success, "false" on failure (e.g. malloc failed).
973 bool dvmCreateStackTraceArray(const void* fp, const Method*** pArray,
976 const Method** array;
979 depth = dvmComputeExactFrameDepth(fp);
980 array = (const Method**) malloc(depth * sizeof(Method*));
984 for (idx = 0; fp != NULL; fp = SAVEAREA_FROM_FP(fp)->prevFrame) {
985 if (!dvmIsBreakFrame(fp))
986 array[idx++] = SAVEAREA_FROM_FP(fp)->method;
988 assert(idx == depth);
996 * Open up the reserved area and throw an exception. The reserved area
997 * should only be needed to create and initialize the exception itself.
999 * If we already opened it and we're continuing to overflow, abort the VM.
1001 * We have to leave the "reserved" area open until the "catch" handler has
1002 * finished doing its processing. This is because the catch handler may
1003 * need to resolve classes, which requires calling into the class loader if
1004 * the classes aren't already in the "initiating loader" list.
1006 void dvmHandleStackOverflow(Thread* self, const Method* method)
1009 * Can we make the reserved area available?
1011 if (self->stackOverflowed) {
1013 * Already did, nothing to do but bail.
1015 LOGE("DalvikVM: double-overflow of stack in threadid=%d; aborting\n",
1017 dvmDumpThread(self, false);
1021 /* open it up to the full range */
1022 LOGI("threadid=%d: stack overflow on call to %s.%s:%s\n",
1024 method->clazz->descriptor, method->name, method->shorty);
1025 StackSaveArea* saveArea = SAVEAREA_FROM_FP(self->curFrame);
1026 LOGI(" method requires %d+%d+%d=%d bytes, fp is %p (%d left)\n",
1027 method->registersSize * 4, sizeof(StackSaveArea), method->outsSize * 4,
1028 (method->registersSize + method->outsSize) * 4 + sizeof(StackSaveArea),
1029 saveArea, (u1*) saveArea - self->interpStackEnd);
1030 LOGI(" expanding stack end (%p to %p)\n", self->interpStackEnd,
1031 self->interpStackStart - self->interpStackSize);
1032 //dvmDumpThread(self, false);
1033 self->interpStackEnd = self->interpStackStart - self->interpStackSize;
1034 self->stackOverflowed = true;
1037 * If we were trying to throw an exception when the stack overflowed,
1038 * we will blow up when doing the class lookup on StackOverflowError
1039 * because of the pending exception. So, we clear it and make it
1040 * the cause of the SOE.
1042 Object* excep = dvmGetException(self);
1043 if (excep != NULL) {
1044 LOGW("Stack overflow while throwing exception\n");
1045 dvmClearException(self);
1047 dvmThrowChainedExceptionByClass(gDvm.classJavaLangStackOverflowError,
1052 * Reduce the available stack size. By this point we should have finished
1053 * our overflow processing.
1055 void dvmCleanupStackOverflow(Thread* self, const Object* exception)
1057 const u1* newStackEnd;
1059 assert(self->stackOverflowed);
1061 if (exception->clazz != gDvm.classJavaLangStackOverflowError) {
1062 /* exception caused during SOE, not the SOE itself */
1066 newStackEnd = (self->interpStackStart - self->interpStackSize)
1067 + STACK_OVERFLOW_RESERVE;
1068 if ((u1*)self->curFrame <= newStackEnd) {
1069 LOGE("Can't shrink stack: curFrame is in reserved area (%p %p)\n",
1070 self->interpStackEnd, self->curFrame);
1071 dvmDumpThread(self, false);
1075 self->interpStackEnd = newStackEnd;
1076 self->stackOverflowed = false;
1078 LOGI("Shrank stack (to %p, curFrame is %p)\n", self->interpStackEnd,
1084 * Extract the object that is the target of a monitor-enter instruction
1085 * in the top stack frame of "thread".
1087 * The other thread might be alive, so this has to work carefully.
1089 * We assume the thread list lock is currently held.
1091 * Returns "true" if we successfully recover the object. "*pOwner" will
1092 * be NULL if we can't determine the owner for some reason (e.g. race
1093 * condition on ownership transfer).
1095 static bool extractMonitorEnterObject(Thread* thread, Object** pLockObj,
1098 void* framePtr = thread->curFrame;
1100 if (framePtr == NULL || dvmIsBreakFrame(framePtr))
1103 const StackSaveArea* saveArea = SAVEAREA_FROM_FP(framePtr);
1104 const Method* method = saveArea->method;
1105 const u2* currentPc = saveArea->xtra.currentPc;
1108 if (!dvmLinearAllocContains(method, sizeof(Method))) {
1109 LOGD("ExtrMon: method %p not valid\n", method);
1113 /* check currentPc */
1114 u4 insnsSize = dvmGetMethodInsnsSize(method);
1115 if (currentPc < method->insns ||
1116 currentPc >= method->insns + insnsSize)
1118 LOGD("ExtrMon: insns %p not valid (%p - %p)\n",
1119 currentPc, method->insns, method->insns + insnsSize);
1123 /* check the instruction */
1124 if ((*currentPc & 0xff) != OP_MONITOR_ENTER) {
1125 LOGD("ExtrMon: insn at %p is not monitor-enter (0x%02x)\n",
1126 currentPc, *currentPc & 0xff);
1130 /* get and check the register index */
1131 unsigned int reg = *currentPc >> 8;
1132 if (reg >= method->registersSize) {
1133 LOGD("ExtrMon: invalid register %d (max %d)\n",
1134 reg, method->registersSize);
1138 /* get and check the object in that register */
1139 u4* fp = (u4*) framePtr;
1140 Object* obj = (Object*) fp[reg];
1141 if (!dvmIsValidObject(obj)) {
1142 LOGD("ExtrMon: invalid object %p at %p[%d]\n", obj, fp, reg);
1148 * Try to determine the object's lock holder; it's okay if this fails.
1150 * We're assuming the thread list lock is already held by this thread.
1151 * If it's not, we may be living dangerously if we have to scan through
1152 * the thread list to find a match. (The VM will generally be in a
1153 * suspended state when executing here, so this is a minor concern
1154 * unless we're dumping while threads are running, in which case there's
1155 * a good chance of stuff blowing up anyway.)
1157 *pOwner = dvmGetObjectLockHolder(obj);
1163 * Dump stack frames, starting from the specified frame and moving down.
1165 * Each frame holds a pointer to the currently executing method, and the
1166 * saved program counter from the caller ("previous" frame). This means
1167 * we don't have the PC for the current method on the stack, which is
1168 * pretty reasonable since it's in the "PC register" for the VM. Because
1169 * exceptions need to show the correct line number we actually *do* have
1170 * an updated version in the fame's "xtra.currentPc", but it's unreliable.
1172 * Note "framePtr" could be NULL in rare circumstances.
1174 static void dumpFrames(const DebugOutputTarget* target, void* framePtr,
1177 const StackSaveArea* saveArea;
1178 const Method* method;
1180 const u2* currentPc = NULL;
1184 * The "currentPc" is updated whenever we execute an instruction that
1185 * might throw an exception. Show it here.
1187 if (framePtr != NULL && !dvmIsBreakFrame(framePtr)) {
1188 saveArea = SAVEAREA_FROM_FP(framePtr);
1190 if (saveArea->xtra.currentPc != NULL)
1191 currentPc = saveArea->xtra.currentPc;
1194 while (framePtr != NULL) {
1195 saveArea = SAVEAREA_FROM_FP(framePtr);
1196 method = saveArea->method;
1198 if (dvmIsBreakFrame(framePtr)) {
1199 //dvmPrintDebugMessage(target, " (break frame)\n");
1203 if (currentPc != NULL)
1204 relPc = currentPc - saveArea->method->insns;
1208 char* className = dvmDescriptorToDot(method->clazz->descriptor);
1209 if (dvmIsNativeMethod(method))
1210 dvmPrintDebugMessage(target,
1211 " at %s.%s(Native Method)\n", className, method->name);
1213 dvmPrintDebugMessage(target,
1214 " at %s.%s(%s:%s%d)\n",
1215 className, method->name, dvmGetMethodSourceFile(method),
1216 (relPc >= 0 && first) ? "~" : "",
1217 relPc < 0 ? -1 : dvmLineNumFromPC(method, relPc));
1223 * Decorate WAIT and MONITOR threads with some detail on
1226 * warning: wait status not stable, even in suspend
1228 if (thread->status == THREAD_WAIT ||
1229 thread->status == THREAD_TIMED_WAIT)
1231 Monitor* mon = thread->waitMonitor;
1232 Object* obj = dvmGetMonitorObject(mon);
1234 className = dvmDescriptorToDot(obj->clazz->descriptor);
1235 dvmPrintDebugMessage(target,
1236 " - waiting on <%p> (a %s)\n", obj, className);
1239 } else if (thread->status == THREAD_MONITOR) {
1242 if (extractMonitorEnterObject(thread, &obj, &owner)) {
1243 className = dvmDescriptorToDot(obj->clazz->descriptor);
1244 if (owner != NULL) {
1245 char* threadName = dvmGetThreadName(owner);
1246 dvmPrintDebugMessage(target,
1247 " - waiting to lock <%p> (a %s) held by threadid=%d (%s)\n",
1248 obj, className, owner->threadId, threadName);
1251 dvmPrintDebugMessage(target,
1252 " - waiting to lock <%p> (a %s) held by ???\n",
1262 * Get saved PC for previous frame. There's no savedPc in a "break"
1263 * frame, because that represents native or interpreted code
1264 * invoked by the VM. The saved PC is sitting in the "PC register",
1265 * a local variable on the native stack.
1267 currentPc = saveArea->savedPc;
1271 if (saveArea->prevFrame != NULL && saveArea->prevFrame <= framePtr) {
1272 LOGW("Warning: loop in stack trace at frame %d (%p -> %p)\n",
1273 checkCount, framePtr, saveArea->prevFrame);
1276 framePtr = saveArea->prevFrame;
1279 if (checkCount > 300) {
1280 dvmPrintDebugMessage(target,
1281 " ***** printed %d frames, not showing any more\n",
1286 dvmPrintDebugMessage(target, "\n");
1291 * Dump the stack for the specified thread.
1293 void dvmDumpThreadStack(const DebugOutputTarget* target, Thread* thread)
1295 dumpFrames(target, thread->curFrame, thread);
1299 * Dump the stack for the specified thread, which is still running.
1301 * This is very dangerous, because stack frames are being pushed on and
1302 * popped off, and if the thread exits we'll be looking at freed memory.
1303 * The plan here is to take a snapshot of the stack and then dump that
1304 * to try to minimize the chances of catching it mid-update. This should
1305 * work reasonably well on a single-CPU system.
1307 * There is a small chance that calling here will crash the VM.
1309 void dvmDumpRunningThreadStack(const DebugOutputTarget* target, Thread* thread)
1311 StackSaveArea* saveArea;
1312 const u1* origStack;
1313 u1* stackCopy = NULL;
1314 int origSize, fpOffset;
1316 int depthLimit = 200;
1318 if (thread == NULL || thread->curFrame == NULL) {
1319 dvmPrintDebugMessage(target,
1320 "DumpRunning: Thread at %p has no curFrame (threadid=%d)\n",
1321 thread, (thread != NULL) ? thread->threadId : 0);
1325 /* wait for a full quantum */
1328 /* copy the info we need, then the stack itself */
1329 origSize = thread->interpStackSize;
1330 origStack = (const u1*) thread->interpStackStart - origSize;
1331 stackCopy = (u1*) malloc(origSize);
1332 fpOffset = (u1*) thread->curFrame - origStack;
1333 memcpy(stackCopy, origStack, origSize);
1336 * Run through the stack and rewrite the "prev" pointers.
1338 //LOGI("DR: fpOff=%d (from %p %p)\n",fpOffset, origStack, thread->curFrame);
1339 fp = stackCopy + fpOffset;
1343 if (depthLimit-- < 0) {
1344 /* we're probably screwed */
1345 dvmPrintDebugMessage(target, "DumpRunning: depth limit hit\n");
1348 saveArea = SAVEAREA_FROM_FP(fp);
1349 if (saveArea->prevFrame == NULL)
1352 prevOffset = (u1*) saveArea->prevFrame - origStack;
1353 if (prevOffset < 0 || prevOffset > origSize) {
1354 dvmPrintDebugMessage(target,
1355 "DumpRunning: bad offset found: %d (from %p %p)\n",
1356 prevOffset, origStack, saveArea->prevFrame);
1357 saveArea->prevFrame = NULL;
1361 saveArea->prevFrame = stackCopy + prevOffset;
1362 fp = saveArea->prevFrame;
1366 * We still need to pass the Thread for some monitor wait stuff.
1368 dumpFrames(target, stackCopy + fpOffset, thread);