/*
* We're calling a JNI native method from an internal VM fuction or
* via reflection. This is also used to create the "fake" native-method
* frames at the top of the interpreted stack.
*
* This actually pushes two frames; the first is a "break" frame.
*
* The top frame has additional space for JNI local reference tracking.
*/
bool dvmPushJNIFrame(Thread* self, const Method* method)
{
StackSaveArea* saveBlock;
StackSaveArea* breakSaveBlock;
int stackReq;
u1* stackPtr;
assert(dvmIsNativeMethod(method));
#ifdef WITH_TAINT_TRACKING
/* Interleaved taint tags plus "native hack" spacer */
stackReq = method->registersSize * 8 + 4 // params only
+ sizeof(StackSaveArea) * 2; // break frame + regular frame
#else
stackReq = method->registersSize * 4 // params only
+ sizeof(StackSaveArea) * 2; // break frame + regular frame
#endif
if (self->curFrame != NULL)
stackPtr = (u1*) SAVEAREA_FROM_FP(self->curFrame);
else
stackPtr = self->interpStackStart;
if (stackPtr - stackReq < self->interpStackEnd) {
/* not enough space */
LOGW("Stack overflow on call to native "
"(req=%d top=%p cur=%p size=%d '%s')\n",
stackReq, self->interpStackStart, self->curFrame,
self->interpStackSize, method->name);
dvmHandleStackOverflow(self, method);
assert(dvmCheckException(self));
return false;
}
/*
* Shift the stack pointer down, leaving space for just the stack save
* area for the break frame, then shift down farther for the full frame.
* We leave space for the method args, which are copied in later.
*/
stackPtr -= sizeof(StackSaveArea);
breakSaveBlock = (StackSaveArea*)stackPtr;
#ifdef WITH_TAINT_TRACKING
/* interleaved taint tags plus "native hack" spacer */
stackPtr -= method->registersSize * 8 + 4 + sizeof(StackSaveArea);
#else
stackPtr -= method->registersSize * 4 + sizeof(StackSaveArea);
#endif
saveBlock = (StackSaveArea*) stackPtr;
#if !defined(NDEBUG) && !defined(PAD_SAVE_AREA)
/* debug -- memset the new stack */
memset(stackPtr, 0xaf, stackReq);
#endif
#ifdef EASY_GDB
if (self->curFrame == NULL)
breakSaveBlock->prevSave = NULL;
else
breakSaveBlock->prevSave = FP_FROM_SAVEAREA(self->curFrame);
saveBlock->prevSave = breakSaveBlock;
#endif
breakSaveBlock->prevFrame = self->curFrame;
breakSaveBlock->savedPc = NULL; // not required
breakSaveBlock->xtra.localRefCookie = 0; // not required
breakSaveBlock->method = NULL;
saveBlock->prevFrame = FP_FROM_SAVEAREA(breakSaveBlock);
saveBlock->savedPc = NULL; // not required
#ifdef USE_INDIRECT_REF
saveBlock->xtra.localRefCookie = self->jniLocalRefTable.segmentState.all;
#else
saveBlock->xtra.localRefCookie = self->jniLocalRefTable.nextEntry;
#endif
saveBlock->method = method;
LOGVV("PUSH JNI frame: old=%p new=%p (size=%d)\n",
self->curFrame, FP_FROM_SAVEAREA(saveBlock),
(u1*)self->curFrame - (u1*)FP_FROM_SAVEAREA(saveBlock));
self->curFrame = FP_FROM_SAVEAREA(saveBlock);
return true;
}
/*
* We're calling an interpreted method from an internal VM function or
* via reflection.
*
* Push a frame for an interpreted method onto the stack. This is only
* used when calling into interpreted code from native code. (The
* interpreter does its own stack frame manipulation for interp-->interp
* calls.)
*
* The size we need to reserve is the sum of parameters, local variables,
* saved goodies, and outbound parameters.
*
* We start by inserting a "break" frame, which ensures that the interpreter
* hands control back to us after the function we call returns or an
* uncaught exception is thrown.
*/
static bool dvmPushInterpFrame(Thread* self, const Method* method)
{
StackSaveArea* saveBlock;
StackSaveArea* breakSaveBlock;
int stackReq;
u1* stackPtr;
assert(!dvmIsNativeMethod(method));
assert(!dvmIsAbstractMethod(method));
stackReq = method->registersSize * 4 // params + locals
+ sizeof(StackSaveArea) * 2 // break frame + regular frame
+ method->outsSize * 4; // args to other methods
if (self->curFrame != NULL)
stackPtr = (u1*) SAVEAREA_FROM_FP(self->curFrame);
else
stackPtr = self->interpStackStart;
if (stackPtr - stackReq < self->interpStackEnd) {
/* not enough space */
LOGW("Stack overflow on call to interp (top=%p cur=%p size=%d %s.%s)\n",
self->interpStackStart, self->curFrame, self->interpStackSize,
method->clazz->descriptor, method->name);
dvmHandleStackOverflow(self);
assert(dvmCheckException(self));
return false;
}
/*
* Shift the stack pointer down, leaving space for the function's
* args/registers and save area.
*/
stackPtr -= sizeof(StackSaveArea);
breakSaveBlock = (StackSaveArea*)stackPtr;
stackPtr -= method->registersSize * 4 + sizeof(StackSaveArea);
saveBlock = (StackSaveArea*) stackPtr;
#if !defined(NDEBUG) && !defined(PAD_SAVE_AREA)
/* debug -- memset the new stack, unless we want valgrind's help */
memset(stackPtr - (method->outsSize*4), 0xaf, stackReq);
#endif
#ifdef EASY_GDB
breakSaveBlock->prevSave = FP_FROM_SAVEAREA(self->curFrame);
saveBlock->prevSave = breakSaveBlock;
#endif
breakSaveBlock->prevFrame = self->curFrame;
breakSaveBlock->savedPc = NULL; // not required
breakSaveBlock->xtra.localRefTop = NULL; // not required
breakSaveBlock->method = NULL;
saveBlock->prevFrame = FP_FROM_SAVEAREA(breakSaveBlock);
saveBlock->savedPc = NULL; // not required
saveBlock->xtra.currentPc = NULL; // not required?
saveBlock->method = method;
LOGVV("PUSH frame: old=%p new=%p (size=%d)\n",
self->curFrame, FP_FROM_SAVEAREA(saveBlock),
(u1*)self->curFrame - (u1*)FP_FROM_SAVEAREA(saveBlock));
self->curFrame = FP_FROM_SAVEAREA(saveBlock);
return true;
}
