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/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* Main interpreter entry point and support functions.
*
* The entry point selects the "standard" or "debug" interpreter and
* facilitates switching between them. The standard interpreter may
* use the "fast" or "portable" implementation.
*
* Some debugger support functions are included here.
*/
#include "Dalvik.h"
#include "interp/InterpDefs.h"
#if defined(WITH_JIT)
#include "interp/Jit.h"
#endif
/*
* ===========================================================================
* Debugger support
* ===========================================================================
*/
// fwd
static BreakpointSet* dvmBreakpointSetAlloc(void);
static void dvmBreakpointSetFree(BreakpointSet* pSet);
/*
* Initialize global breakpoint structures.
*/
bool dvmBreakpointStartup(void)
{
gDvm.breakpointSet = dvmBreakpointSetAlloc();
return (gDvm.breakpointSet != NULL);
}
/*
* Free resources.
*/
void dvmBreakpointShutdown(void)
{
dvmBreakpointSetFree(gDvm.breakpointSet);
}
/*
* This represents a breakpoint inserted in the instruction stream.
*
* The debugger may ask us to create the same breakpoint multiple times.
* We only remove the breakpoint when the last instance is cleared.
*/
typedef struct {
Method* method; /* method we're associated with */
u2* addr; /* absolute memory address */
u1 originalOpcode; /* original 8-bit opcode value */
int setCount; /* #of times this breakpoint was set */
} Breakpoint;
/*
* Set of breakpoints.
*/
struct BreakpointSet {
/* grab lock before reading or writing anything else in here */
pthread_mutex_t lock;
/* vector of breakpoint structures */
int alloc;
int count;
Breakpoint* breakpoints;
};
/*
* Initialize a BreakpointSet. Initially empty.
*/
static BreakpointSet* dvmBreakpointSetAlloc(void)
{
BreakpointSet* pSet = (BreakpointSet*) calloc(1, sizeof(*pSet));
dvmInitMutex(&pSet->lock);
/* leave the rest zeroed -- will alloc on first use */
return pSet;
}
/*
* Free storage associated with a BreakpointSet.
*/
static void dvmBreakpointSetFree(BreakpointSet* pSet)
{
if (pSet == NULL)
return;
free(pSet->breakpoints);
free(pSet);
}
/*
* Lock the breakpoint set.
*
* It's not currently necessary to switch to VMWAIT in the event of
* contention, because nothing in here can block. However, it's possible
* that the bytecode-updater code could become fancier in the future, so
* we do the trylock dance as a bit of future-proofing.
*/
static void dvmBreakpointSetLock(BreakpointSet* pSet)
{
if (dvmTryLockMutex(&pSet->lock) != 0) {
Thread* self = dvmThreadSelf();
ThreadStatus oldStatus = dvmChangeStatus(self, THREAD_VMWAIT);
dvmLockMutex(&pSet->lock);
dvmChangeStatus(self, oldStatus);
}
}
/*
* Unlock the breakpoint set.
*/
static void dvmBreakpointSetUnlock(BreakpointSet* pSet)
{
dvmUnlockMutex(&pSet->lock);
}
/*
* Return the #of breakpoints.
*/
static int dvmBreakpointSetCount(const BreakpointSet* pSet)
{
return pSet->count;
}
/*
* See if we already have an entry for this address.
*
* The BreakpointSet's lock must be acquired before calling here.
*
* Returns the index of the breakpoint entry, or -1 if not found.
*/
static int dvmBreakpointSetFind(const BreakpointSet* pSet, const u2* addr)
{
int i;
for (i = 0; i < pSet->count; i++) {
Breakpoint* pBreak = &pSet->breakpoints[i];
if (pBreak->addr == addr)
return i;
}
return -1;
}
/*
* Retrieve the opcode that was originally at the specified location.
*
* The BreakpointSet's lock must be acquired before calling here.
*
* Returns "true" with the opcode in *pOrig on success.
*/
static bool dvmBreakpointSetOriginalOpcode(const BreakpointSet* pSet,
const u2* addr, u1* pOrig)
{
int idx = dvmBreakpointSetFind(pSet, addr);
if (idx < 0)
return false;
*pOrig = pSet->breakpoints[idx].originalOpcode;
return true;
}
/*
* Check the opcode. If it's a "magic" NOP, indicating the start of
* switch or array data in the instruction stream, we don't want to set
* a breakpoint.
*
* This can happen because the line number information dx generates
* associates the switch data with the switch statement's line number,
* and some debuggers put breakpoints at every address associated with
* a given line. The result is that the breakpoint stomps on the NOP
* instruction that doubles as a data table magic number, and an explicit
* check in the interpreter results in an exception being thrown.
*
* We don't want to simply refuse to add the breakpoint to the table,
* because that confuses the housekeeping. We don't want to reject the
* debugger's event request, and we want to be sure that there's exactly
* one un-set operation for every set op.
*/
static bool instructionIsMagicNop(const u2* addr)
{
u2 curVal = *addr;
return ((GET_OPCODE(curVal)) == OP_NOP && (curVal >> 8) != 0);
}
/*
* Add a breakpoint at a specific address. If the address is already
* present in the table, this just increments the count.
*
* For a new entry, this will extract and preserve the current opcode from
* the instruction stream, and replace it with a breakpoint opcode.
*
* The BreakpointSet's lock must be acquired before calling here.
*
* Returns "true" on success.
*/
static bool dvmBreakpointSetAdd(BreakpointSet* pSet, Method* method,
unsigned int instrOffset)
{
const int kBreakpointGrowth = 10;
const u2* addr = method->insns + instrOffset;
int idx = dvmBreakpointSetFind(pSet, addr);
Breakpoint* pBreak;
if (idx < 0) {
if (pSet->count == pSet->alloc) {
int newSize = pSet->alloc + kBreakpointGrowth;
Breakpoint* newVec;
LOGV("+++ increasing breakpoint set size to %d\n", newSize);
/* pSet->breakpoints will be NULL on first entry */
newVec = (Breakpoint*)realloc(pSet->breakpoints, newSize * sizeof(Breakpoint));
if (newVec == NULL)
return false;
pSet->breakpoints = newVec;
pSet->alloc = newSize;
}
pBreak = &pSet->breakpoints[pSet->count++];
pBreak->method = method;
pBreak->addr = (u2*)addr;
pBreak->originalOpcode = *(u1*)addr;
pBreak->setCount = 1;
/*
* Change the opcode. We must ensure that the BreakpointSet
* updates happen before we change the opcode.
*
* If the method has not been verified, we do NOT insert the
* breakpoint yet, since that will screw up the verifier. The
* debugger is allowed to insert breakpoints in unverified code,
* but since we don't execute unverified code we don't need to
* alter the bytecode yet.
*
* The class init code will "flush" all pending opcode writes
* before verification completes.
*/
assert(*(u1*)addr != OP_BREAKPOINT);
if (dvmIsClassVerified(method->clazz)) {
LOGV("Class %s verified, adding breakpoint at %p\n",
method->clazz->descriptor, addr);
if (instructionIsMagicNop(addr)) {
LOGV("Refusing to set breakpoint on %04x at %s.%s + 0x%x\n",
*addr, method->clazz->descriptor, method->name,
instrOffset);
} else {
ANDROID_MEMBAR_FULL();
dvmDexChangeDex1(method->clazz->pDvmDex, (u1*)addr,
OP_BREAKPOINT);
}
} else {
LOGV("Class %s NOT verified, deferring breakpoint at %p\n",
method->clazz->descriptor, addr);
}
} else {
/*
* Breakpoint already exists, just increase the count.
*/
pBreak = &pSet->breakpoints[idx];
pBreak->setCount++;
}
return true;
}
/*
* Remove one instance of the specified breakpoint. When the count
* reaches zero, the entry is removed from the table, and the original
* opcode is restored.
*
* The BreakpointSet's lock must be acquired before calling here.
*/
static void dvmBreakpointSetRemove(BreakpointSet* pSet, Method* method,
unsigned int instrOffset)
{
const u2* addr = method->insns + instrOffset;
int idx = dvmBreakpointSetFind(pSet, addr);
if (idx < 0) {
/* breakpoint not found in set -- unexpected */
if (*(u1*)addr == OP_BREAKPOINT) {
LOGE("Unable to restore breakpoint opcode (%s.%s +0x%x)\n",
method->clazz->descriptor, method->name, instrOffset);
dvmAbort();
} else {
LOGW("Breakpoint was already restored? (%s.%s +0x%x)\n",
method->clazz->descriptor, method->name, instrOffset);
}
} else {
Breakpoint* pBreak = &pSet->breakpoints[idx];
if (pBreak->setCount == 1) {
/*
* Must restore opcode before removing set entry.
*
* If the breakpoint was never flushed, we could be ovewriting
* a value with the same value. Not a problem, though we
* could end up causing a copy-on-write here when we didn't
* need to. (Not worth worrying about.)
*/
dvmDexChangeDex1(method->clazz->pDvmDex, (u1*)addr,
pBreak->originalOpcode);
ANDROID_MEMBAR_FULL();
if (idx != pSet->count-1) {
/* shift down */
memmove(&pSet->breakpoints[idx], &pSet->breakpoints[idx+1],
(pSet->count-1 - idx) * sizeof(pSet->breakpoints[0]));
}
pSet->count--;
pSet->breakpoints[pSet->count].addr = (u2*) 0xdecadead; // debug
} else {
pBreak->setCount--;
assert(pBreak->setCount > 0);
}
}
}
/*
* Flush any breakpoints associated with methods in "clazz". We want to
* change the opcode, which might not have happened when the breakpoint
* was initially set because the class was in the process of being
* verified.
*
* The BreakpointSet's lock must be acquired before calling here.
*/
static void dvmBreakpointSetFlush(BreakpointSet* pSet, ClassObject* clazz)
{
int i;
for (i = 0; i < pSet->count; i++) {
Breakpoint* pBreak = &pSet->breakpoints[i];
if (pBreak->method->clazz == clazz) {
/*
* The breakpoint is associated with a method in this class.
* It might already be there or it might not; either way,
* flush it out.
*/
LOGV("Flushing breakpoint at %p for %s\n",
pBreak->addr, clazz->descriptor);
if (instructionIsMagicNop(pBreak->addr)) {
LOGV("Refusing to flush breakpoint on %04x at %s.%s + 0x%x\n",
*pBreak->addr, pBreak->method->clazz->descriptor,
pBreak->method->name, pBreak->addr - pBreak->method->insns);
} else {
dvmDexChangeDex1(clazz->pDvmDex, (u1*)pBreak->addr,
OP_BREAKPOINT);
}
}
}
}
/*
* Do any debugger-attach-time initialization.
*/
void dvmInitBreakpoints(void)
{
/* quick sanity check */
BreakpointSet* pSet = gDvm.breakpointSet;
dvmBreakpointSetLock(pSet);
if (dvmBreakpointSetCount(pSet) != 0) {
LOGW("WARNING: %d leftover breakpoints\n", dvmBreakpointSetCount(pSet));
/* generally not good, but we can keep going */
}
dvmBreakpointSetUnlock(pSet);
}
/*
* Add an address to the list, putting it in the first non-empty slot.
*
* Sometimes the debugger likes to add two entries for one breakpoint.
* We add two entries here, so that we get the right behavior when it's
* removed twice.
*
* This will only be run from the JDWP thread, and it will happen while
* we are updating the event list, which is synchronized. We're guaranteed
* to be the only one adding entries, and the lock ensures that nobody
* will be trying to remove them while we're in here.
*
* "addr" is the absolute address of the breakpoint bytecode.
*/
void dvmAddBreakAddr(Method* method, unsigned int instrOffset)
{
BreakpointSet* pSet = gDvm.breakpointSet;
dvmBreakpointSetLock(pSet);
dvmBreakpointSetAdd(pSet, method, instrOffset);
dvmBreakpointSetUnlock(pSet);
}
/*
* Remove an address from the list by setting the entry to NULL.
*
* This can be called from the JDWP thread (because the debugger has
* cancelled the breakpoint) or from an event thread (because it's a
* single-shot breakpoint, e.g. "run to line"). We only get here as
* the result of removing an entry from the event list, which is
* synchronized, so it should not be possible for two threads to be
* updating breakpoints at the same time.
*/
void dvmClearBreakAddr(Method* method, unsigned int instrOffset)
{
BreakpointSet* pSet = gDvm.breakpointSet;
dvmBreakpointSetLock(pSet);
dvmBreakpointSetRemove(pSet, method, instrOffset);
dvmBreakpointSetUnlock(pSet);
}
/*
* Get the original opcode from under a breakpoint.
*
* On SMP hardware it's possible one core might try to execute a breakpoint
* after another core has cleared it. We need to handle the case where
* there's no entry in the breakpoint set. (The memory barriers in the
* locks and in the breakpoint update code should ensure that, once we've
* observed the absence of a breakpoint entry, we will also now observe
* the restoration of the original opcode. The fact that we're holding
* the lock prevents other threads from confusing things further.)
*/
u1 dvmGetOriginalOpcode(const u2* addr)
{
BreakpointSet* pSet = gDvm.breakpointSet;
u1 orig = 0;
dvmBreakpointSetLock(pSet);
if (!dvmBreakpointSetOriginalOpcode(pSet, addr, &orig)) {
orig = *(u1*)addr;
if (orig == OP_BREAKPOINT) {
LOGE("GLITCH: can't find breakpoint, opcode is still set\n");
dvmAbort();
}
}
dvmBreakpointSetUnlock(pSet);
return orig;
}
/*
* Flush any breakpoints associated with methods in "clazz".
*
* We don't want to modify the bytecode of a method before the verifier
* gets a chance to look at it, so we postpone opcode replacement until
* after verification completes.
*/
void dvmFlushBreakpoints(ClassObject* clazz)
{
BreakpointSet* pSet = gDvm.breakpointSet;
if (pSet == NULL)
return;
assert(dvmIsClassVerified(clazz));
dvmBreakpointSetLock(pSet);
dvmBreakpointSetFlush(pSet, clazz);
dvmBreakpointSetUnlock(pSet);
}
/*
* Add a single step event. Currently this is a global item.
*
* We set up some initial values based on the thread's current state. This
* won't work well if the thread is running, so it's up to the caller to
* verify that it's suspended.
*
* This is only called from the JDWP thread.
*/
bool dvmAddSingleStep(Thread* thread, int size, int depth)
{
StepControl* pCtrl = &gDvm.stepControl;
if (pCtrl->active && thread != pCtrl->thread) {
LOGW("WARNING: single-step active for %p; adding %p\n",
pCtrl->thread, thread);
/*
* Keep going, overwriting previous. This can happen if you
* suspend a thread in Object.wait, hit the single-step key, then
* switch to another thread and do the same thing again.
* The first thread's step is still pending.
*
* TODO: consider making single-step per-thread. Adds to the
* overhead, but could be useful in rare situations.
*/
}
pCtrl->size = size;
pCtrl->depth = depth;
pCtrl->thread = thread;
/*
* We may be stepping into or over method calls, or running until we
* return from the current method. To make this work we need to track
* the current line, current method, and current stack depth. We need
* to be checking these after most instructions, notably those that
* call methods, return from methods, or are on a different line from the
* previous instruction.
*
* We have to start with a snapshot of the current state. If we're in
* an interpreted method, everything we need is in the current frame. If
* we're in a native method, possibly with some extra JNI frames pushed
* on by PushLocalFrame, we want to use the topmost native method.
*/
const StackSaveArea* saveArea;
void* fp;
void* prevFp = NULL;
for (fp = thread->curFrame; fp != NULL; fp = saveArea->prevFrame) {
const Method* method;
saveArea = SAVEAREA_FROM_FP(fp);
method = saveArea->method;
if (!dvmIsBreakFrame((u4*)fp) && !dvmIsNativeMethod(method))
break;
prevFp = fp;
}
if (fp == NULL) {
LOGW("Unexpected: step req in native-only threadid=%d\n",
thread->threadId);
return false;
}
if (prevFp != NULL) {
/*
* First interpreted frame wasn't the one at the bottom. Break
* frames are only inserted when calling from native->interp, so we
* don't need to worry about one being here.
*/
LOGV("##### init step while in native method\n");
fp = prevFp;
assert(!dvmIsBreakFrame((u4*)fp));
assert(dvmIsNativeMethod(SAVEAREA_FROM_FP(fp)->method));
saveArea = SAVEAREA_FROM_FP(fp);
}
/*
* Pull the goodies out. "xtra.currentPc" should be accurate since
* we update it on every instruction while the debugger is connected.
*/
pCtrl->method = saveArea->method;
// Clear out any old address set
if (pCtrl->pAddressSet != NULL) {
// (discard const)
free((void *)pCtrl->pAddressSet);
pCtrl->pAddressSet = NULL;
}
if (dvmIsNativeMethod(pCtrl->method)) {
pCtrl->line = -1;
} else {
pCtrl->line = dvmLineNumFromPC(saveArea->method,
saveArea->xtra.currentPc - saveArea->method->insns);
pCtrl->pAddressSet
= dvmAddressSetForLine(saveArea->method, pCtrl->line);
}
pCtrl->frameDepth = dvmComputeVagueFrameDepth(thread, thread->curFrame);
pCtrl->active = true;
LOGV("##### step init: thread=%p meth=%p '%s' line=%d frameDepth=%d depth=%s size=%s\n",
pCtrl->thread, pCtrl->method, pCtrl->method->name,
pCtrl->line, pCtrl->frameDepth,
dvmJdwpStepDepthStr(pCtrl->depth),
dvmJdwpStepSizeStr(pCtrl->size));
return true;
}
/*
* Disable a single step event.
*/
void dvmClearSingleStep(Thread* thread)
{
UNUSED_PARAMETER(thread);
gDvm.stepControl.active = false;
}
/*
* The interpreter just threw. Handle any special subMode requirements.
*/
void dvmReportExceptionThrow(Thread* self, const Method* curMethod,
const u2* pc, void* fp)
{
#if defined(WITH_JIT)
if (self->interpBreak.ctl.subMode & kSubModeJitTraceBuild) {
dvmJitEndTraceSelect(self, pc);
}
if (self->interpBreak.ctl.breakFlags & kInterpSingleStep) {
/* Discard any single-step native returns to translation */
self->jitResumeNPC = NULL;
}
#endif
if (self->interpBreak.ctl.subMode & kSubModeDebuggerActive) {
void *catchFrame;
int offset = pc - curMethod->insns;
int catchRelPc = dvmFindCatchBlock(self, offset, self->exception,
true, &catchFrame);
dvmDbgPostException(fp, offset, catchFrame, catchRelPc,
self->exception);
}
}
/*
* The interpreter is preparing to do an invoke (both native & normal).
* Handle any special subMode requirements.
*/
void dvmReportInvoke(Thread* self, const Method* methodToCall)
{
TRACE_METHOD_ENTER(self, methodToCall);
}
/*
* The interpreter is preparing to do a native invoke. Handle any
* special subMode requirements. NOTE: for a native invoke,
* dvmReportInvoke() and dvmReportPreNativeInvoke() will both
* be called prior to the invoke.
*/
void dvmReportPreNativeInvoke(const u2* pc, Thread* self,
const Method* methodToCall)
{
#if defined(WITH_JIT)
/*
* Actively building a trace? If so, end it now. The trace
* builder can't follow into or through a native method.
*/
if (self->interpBreak.ctl.subMode & kSubModeJitTraceBuild) {
dvmCheckJit(pc, self);
}
#endif
if (self->interpBreak.ctl.subMode & kSubModeDebuggerActive) {
Object* thisPtr = dvmGetThisPtr(self->interpSave.method,
self->interpSave.fp);
assert(thisPtr != NULL && !dvmIsValidObject(thisPtr));
dvmDbgPostLocationEvent(methodToCall, -1, thisPtr, DBG_METHOD_ENTRY);
}
}
/*
* The interpreter has returned from a native invoke. Handle any
* special subMode requirements.
*/
void dvmReportPostNativeInvoke(const u2* pc, Thread* self,
const Method* methodToCall)
{
if (self->interpBreak.ctl.subMode & kSubModeDebuggerActive) {
Object* thisPtr = dvmGetThisPtr(self->interpSave.method,
self->interpSave.fp);
assert(thisPtr != NULL && !dvmIsValidObject(thisPtr));
dvmDbgPostLocationEvent(methodToCall, -1, thisPtr, DBG_METHOD_EXIT);
}
if (self->interpBreak.ctl.subMode & kSubModeMethodTrace) {
dvmFastNativeMethodTraceExit(methodToCall, self);
}
}
/*
* The interpreter has returned from a normal method. Handle any special
* subMode requirements.
*/
void dvmReportReturn(Thread* self, const u2* pc, const u4* prevFP)
{
TRACE_METHOD_EXIT(self, self->interpSave.method);
#if defined(WITH_JIT)
if (dvmIsBreakFrame(prevFP) &&
(self->interpBreak.ctl.subMode & kSubModeJitTraceBuild)) {
dvmCheckJit(pc, self);
}
#endif
}
/*
* Update the debugger on interesting events, such as hitting a breakpoint
* or a single-step point. This is called from the top of the interpreter
* loop, before the current instruction is processed.
*
* Set "methodEntry" if we've just entered the method. This detects
* method exit by checking to see if the next instruction is "return".
*
* This can't catch native method entry/exit, so we have to handle that
* at the point of invocation. We also need to catch it in dvmCallMethod
* if we want to capture native->native calls made through JNI.
*
* Notes to self:
* - Don't want to switch to VMWAIT while posting events to the debugger.
* Let the debugger code decide if we need to change state.
* - We may want to check for debugger-induced thread suspensions on
* every instruction. That would make a "suspend all" more responsive
* and reduce the chances of multiple simultaneous events occurring.
* However, it could change the behavior some.
*
* TODO: method entry/exit events are probably less common than location
* breakpoints. We may be able to speed things up a bit if we don't query
* the event list unless we know there's at least one lurking within.
*/
void dvmUpdateDebugger(const Method* method, const u2* pc, const u4* fp,
bool methodEntry, Thread* self)
{
int eventFlags = 0;
/*
* Update xtra.currentPc on every instruction. We need to do this if
* there's a chance that we could get suspended. This can happen if
* eventFlags != 0 here, or somebody manually requests a suspend
* (which gets handled at PERIOD_CHECKS time). One place where this
* needs to be correct is in dvmAddSingleStep().
*/
dvmExportPC(pc, fp);
if (methodEntry)
eventFlags |= DBG_METHOD_ENTRY;
/*
* See if we have a breakpoint here.
*
* Depending on the "mods" associated with event(s) on this address,
* we may or may not actually send a message to the debugger.
*/
if (GET_OPCODE(*pc) == OP_BREAKPOINT) {
LOGV("+++ breakpoint hit at %p\n", pc);
eventFlags |= DBG_BREAKPOINT;
}
/*
* If the debugger is single-stepping one of our threads, check to
* see if we're that thread and we've reached a step point.
*/
const StepControl* pCtrl = &gDvm.stepControl;
if (pCtrl->active && pCtrl->thread == self) {
int frameDepth;
bool doStop = false;
const char* msg = NULL;
assert(!dvmIsNativeMethod(method));
if (pCtrl->depth == SD_INTO) {
/*
* Step into method calls. We break when the line number
* or method pointer changes. If we're in SS_MIN mode, we
* always stop.
*/
if (pCtrl->method != method) {
doStop = true;
msg = "new method";
} else if (pCtrl->size == SS_MIN) {
doStop = true;
msg = "new instruction";
} else if (!dvmAddressSetGet(
pCtrl->pAddressSet, pc - method->insns)) {
doStop = true;
msg = "new line";
}
} else if (pCtrl->depth == SD_OVER) {
/*
* Step over method calls. We break when the line number is
* different and the frame depth is <= the original frame
* depth. (We can't just compare on the method, because we
* might get unrolled past it by an exception, and it's tricky
* to identify recursion.)
*/
frameDepth = dvmComputeVagueFrameDepth(self, fp);
if (frameDepth < pCtrl->frameDepth) {
/* popped up one or more frames, always trigger */
doStop = true;
msg = "method pop";
} else if (frameDepth == pCtrl->frameDepth) {
/* same depth, see if we moved */
if (pCtrl->size == SS_MIN) {
doStop = true;
msg = "new instruction";
} else if (!dvmAddressSetGet(pCtrl->pAddressSet,
pc - method->insns)) {
doStop = true;
msg = "new line";
}
}
} else {
assert(pCtrl->depth == SD_OUT);
/*
* Return from the current method. We break when the frame
* depth pops up.
*
* This differs from the "method exit" break in that it stops
* with the PC at the next instruction in the returned-to
* function, rather than the end of the returning function.
*/
frameDepth = dvmComputeVagueFrameDepth(self, fp);
if (frameDepth < pCtrl->frameDepth) {
doStop = true;
msg = "method pop";
}
}
if (doStop) {
LOGV("#####S %s\n", msg);
eventFlags |= DBG_SINGLE_STEP;
}
}
/*
* Check to see if this is a "return" instruction. JDWP says we should
* send the event *after* the code has been executed, but it also says
* the location we provide is the last instruction. Since the "return"
* instruction has no interesting side effects, we should be safe.
* (We can't just move this down to the returnFromMethod label because
* we potentially need to combine it with other events.)
*
* We're also not supposed to generate a method exit event if the method
* terminates "with a thrown exception".
*/
u2 opcode = GET_OPCODE(*pc);
if (opcode == OP_RETURN_VOID || opcode == OP_RETURN ||
opcode == OP_RETURN_WIDE ||opcode == OP_RETURN_OBJECT)
{
eventFlags |= DBG_METHOD_EXIT;
}
/*
* If there's something interesting going on, see if it matches one
* of the debugger filters.
*/
if (eventFlags != 0) {
Object* thisPtr = dvmGetThisPtr(method, fp);
if (thisPtr != NULL && !dvmIsValidObject(thisPtr)) {
/*
* TODO: remove this check if we're confident that the "this"
* pointer is where it should be -- slows us down, especially
* during single-step.
*/
char* desc = dexProtoCopyMethodDescriptor(&method->prototype);
LOGE("HEY: invalid 'this' ptr %p (%s.%s %s)\n", thisPtr,
method->clazz->descriptor, method->name, desc);
free(desc);
dvmAbort();
}
dvmDbgPostLocationEvent(method, pc - method->insns, thisPtr,
eventFlags);
}
}
/*
* Recover the "this" pointer from the current interpreted method. "this"
* is always in "in0" for non-static methods.
*
* The "ins" start at (#of registers - #of ins). Note in0 != v0.
*
* This works because "dx" guarantees that it will work. It's probably
* fairly common to have a virtual method that doesn't use its "this"
* pointer, in which case we're potentially wasting a register. However,
* the debugger doesn't treat "this" as just another argument. For
* example, events (such as breakpoints) can be enabled for specific
* values of "this". There is also a separate StackFrame.ThisObject call
* in JDWP that is expected to work for any non-native non-static method.
*
* Because we need it when setting up debugger event filters, we want to
* be able to do this quickly.
*/
Object* dvmGetThisPtr(const Method* method, const u4* fp)
{
if (dvmIsStaticMethod(method))
return NULL;
return (Object*)fp[method->registersSize - method->insSize];
}
#if defined(WITH_TRACKREF_CHECKS)
/*
* Verify that all internally-tracked references have been released. If
* they haven't, print them and abort the VM.
*
* "debugTrackedRefStart" indicates how many refs were on the list when
* we were first invoked.
*/
void dvmInterpCheckTrackedRefs(Thread* self, const Method* method,
int debugTrackedRefStart)
{
if (dvmReferenceTableEntries(&self->internalLocalRefTable)
!= (size_t) debugTrackedRefStart)
{
char* desc;
Object** top;
int count;
count = dvmReferenceTableEntries(&self->internalLocalRefTable);
LOGE("TRACK: unreleased internal reference (prev=%d total=%d)\n",
debugTrackedRefStart, count);
desc = dexProtoCopyMethodDescriptor(&method->prototype);
LOGE(" current method is %s.%s %s\n", method->clazz->descriptor,
method->name, desc);
free(desc);
top = self->internalLocalRefTable.table + debugTrackedRefStart;
while (top < self->internalLocalRefTable.nextEntry) {
LOGE(" %p (%s)\n",
*top,
((*top)->clazz != NULL) ? (*top)->clazz->descriptor : "");
top++;
}
dvmDumpThread(self, false);
dvmAbort();
}
//LOGI("TRACK OK\n");
}
#endif
#ifdef LOG_INSTR
/*
* Dump the v-registers. Sent to the ILOG log tag.
*/
void dvmDumpRegs(const Method* method, const u4* framePtr, bool inOnly)
{
int i, localCount;
localCount = method->registersSize - method->insSize;
LOG(LOG_VERBOSE, LOG_TAG"i", "Registers (fp=%p):\n", framePtr);
for (i = method->registersSize-1; i >= 0; i--) {
if (i >= localCount) {
LOG(LOG_VERBOSE, LOG_TAG"i", " v%-2d in%-2d : 0x%08x\n",
i, i-localCount, framePtr[i]);
} else {
if (inOnly) {
LOG(LOG_VERBOSE, LOG_TAG"i", " [...]\n");
break;
}
const char* name = "";
#if 0 // "locals" structure has changed -- need to rewrite this
int j;
DexFile* pDexFile = method->clazz->pDexFile;
const DexCode* pDexCode = dvmGetMethodCode(method);
int localsSize = dexGetLocalsSize(pDexFile, pDexCode);
const DexLocal* locals = dvmDexGetLocals(pDexFile, pDexCode);
for (j = 0; j < localsSize, j++) {
if (locals[j].registerNum == (u4) i) {
name = dvmDexStringStr(locals[j].pName);
break;
}
}
#endif
LOG(LOG_VERBOSE, LOG_TAG"i", " v%-2d : 0x%08x %s\n",
i, framePtr[i], name);
}
}
}
#endif
/*
* ===========================================================================
* Entry point and general support functions
* ===========================================================================
*/
/*
* Construct an s4 from two consecutive half-words of switch data.
* This needs to check endianness because the DEX optimizer only swaps
* half-words in instruction stream.
*
* "switchData" must be 32-bit aligned.
*/
#if __BYTE_ORDER == __LITTLE_ENDIAN
static inline s4 s4FromSwitchData(const void* switchData) {
return *(s4*) switchData;
}
#else
static inline s4 s4FromSwitchData(const void* switchData) {
u2* data = switchData;
return data[0] | (((s4) data[1]) << 16);
}
#endif
/*
* Find the matching case. Returns the offset to the handler instructions.
*
* Returns 3 if we don't find a match (it's the size of the packed-switch
* instruction).
*/
s4 dvmInterpHandlePackedSwitch(const u2* switchData, s4 testVal)
{
const int kInstrLen = 3;
u2 size;
s4 firstKey;
const s4* entries;
/*
* Packed switch data format:
* ushort ident = 0x0100 magic value
* ushort size number of entries in the table
* int first_key first (and lowest) switch case value
* int targets[size] branch targets, relative to switch opcode
*
* Total size is (4+size*2) 16-bit code units.
*/
if (*switchData++ != kPackedSwitchSignature) {
/* should have been caught by verifier */
dvmThrowInternalError("bad packed switch magic");
return kInstrLen;
}
size = *switchData++;
assert(size > 0);
firstKey = *switchData++;
firstKey |= (*switchData++) << 16;
if (testVal < firstKey || testVal >= firstKey + size) {
LOGVV("Value %d not found in switch (%d-%d)\n",
testVal, firstKey, firstKey+size-1);
return kInstrLen;
}
/* The entries are guaranteed to be aligned on a 32-bit boundary;
* we can treat them as a native int array.
*/
entries = (const s4*) switchData;
assert(((u4)entries & 0x3) == 0);
assert(testVal - firstKey >= 0 && testVal - firstKey < size);
LOGVV("Value %d found in slot %d (goto 0x%02x)\n",
testVal, testVal - firstKey,
s4FromSwitchData(&entries[testVal - firstKey]));
return s4FromSwitchData(&entries[testVal - firstKey]);
}
/*
* Find the matching case. Returns the offset to the handler instructions.
*
* Returns 3 if we don't find a match (it's the size of the sparse-switch
* instruction).
*/
s4 dvmInterpHandleSparseSwitch(const u2* switchData, s4 testVal)
{
const int kInstrLen = 3;
u2 size;
const s4* keys;
const s4* entries;
/*
* Sparse switch data format:
* ushort ident = 0x0200 magic value
* ushort size number of entries in the table; > 0
* int keys[size] keys, sorted low-to-high; 32-bit aligned
* int targets[size] branch targets, relative to switch opcode
*
* Total size is (2+size*4) 16-bit code units.
*/
if (*switchData++ != kSparseSwitchSignature) {
/* should have been caught by verifier */
dvmThrowInternalError("bad sparse switch magic");
return kInstrLen;
}
size = *switchData++;
assert(size > 0);
/* The keys are guaranteed to be aligned on a 32-bit boundary;
* we can treat them as a native int array.
*/
keys = (const s4*) switchData;
assert(((u4)keys & 0x3) == 0);
/* The entries are guaranteed to be aligned on a 32-bit boundary;
* we can treat them as a native int array.
*/
entries = keys + size;
assert(((u4)entries & 0x3) == 0);
/*
* Binary-search through the array of keys, which are guaranteed to
* be sorted low-to-high.
*/
int lo = 0;
int hi = size - 1;
while (lo <= hi) {
int mid = (lo + hi) >> 1;
s4 foundVal = s4FromSwitchData(&keys[mid]);
if (testVal < foundVal) {
hi = mid - 1;
} else if (testVal > foundVal) {
lo = mid + 1;
} else {
LOGVV("Value %d found in entry %d (goto 0x%02x)\n",
testVal, mid, s4FromSwitchData(&entries[mid]));
return s4FromSwitchData(&entries[mid]);
}
}
LOGVV("Value %d not found in switch\n", testVal);
return kInstrLen;
}
/*
* Copy data for a fill-array-data instruction. On a little-endian machine
* we can just do a memcpy(), on a big-endian system we have work to do.
*
* The trick here is that dexopt has byte-swapped each code unit, which is
* exactly what we want for short/char data. For byte data we need to undo
* the swap, and for 4- or 8-byte values we need to swap pieces within
* each word.
*/
static void copySwappedArrayData(void* dest, const u2* src, u4 size, u2 width)
{
#if __BYTE_ORDER == __LITTLE_ENDIAN
memcpy(dest, src, size*width);
#else
int i;
switch (width) {
case 1:
/* un-swap pairs of bytes as we go */
for (i = (size-1) & ~1; i >= 0; i -= 2) {
((u1*)dest)[i] = ((u1*)src)[i+1];
((u1*)dest)[i+1] = ((u1*)src)[i];
}
/*
* "src" is padded to end on a two-byte boundary, but we don't want to
* assume "dest" is, so we handle odd length specially.
*/
if ((size & 1) != 0) {
((u1*)dest)[size-1] = ((u1*)src)[size];
}
break;
case 2:
/* already swapped correctly */
memcpy(dest, src, size*width);
break;
case 4:
/* swap word halves */
for (i = 0; i < (int) size; i++) {
((u4*)dest)[i] = (src[(i << 1) + 1] << 16) | src[i << 1];
}
break;
case 8:
/* swap word halves and words */
for (i = 0; i < (int) (size << 1); i += 2) {
((int*)dest)[i] = (src[(i << 1) + 3] << 16) | src[(i << 1) + 2];
((int*)dest)[i+1] = (src[(i << 1) + 1] << 16) | src[i << 1];
}
break;
default:
LOGE("Unexpected width %d in copySwappedArrayData\n", width);
dvmAbort();
break;
}
#endif
}
/*
* Fill the array with predefined constant values.
*
* Returns true if job is completed, otherwise false to indicate that
* an exception has been thrown.
*/
bool dvmInterpHandleFillArrayData(ArrayObject* arrayObj, const u2* arrayData)
{
u2 width;
u4 size;
if (arrayObj == NULL) {
dvmThrowNullPointerException(NULL);
return false;
}
assert (!IS_CLASS_FLAG_SET(((Object *)arrayObj)->clazz,
CLASS_ISOBJECTARRAY));
/*
* Array data table format:
* ushort ident = 0x0300 magic value
* ushort width width of each element in the table
* uint size number of elements in the table
* ubyte data[size*width] table of data values (may contain a single-byte
* padding at the end)
*
* Total size is 4+(width * size + 1)/2 16-bit code units.
*/
if (arrayData[0] != kArrayDataSignature) {
dvmThrowInternalError("bad array data magic");
return false;
}
width = arrayData[1];
size = arrayData[2] | (((u4)arrayData[3]) << 16);
if (size > arrayObj->length) {
dvmThrowArrayIndexOutOfBoundsException(arrayObj->length, size);
return false;
}
copySwappedArrayData(arrayObj->contents, &arrayData[4], size, width);
return true;
}
/*
* Find the concrete method that corresponds to "methodIdx". The code in
* "method" is executing invoke-method with "thisClass" as its first argument.
*
* Returns NULL with an exception raised on failure.
*/
Method* dvmInterpFindInterfaceMethod(ClassObject* thisClass, u4 methodIdx,
const Method* method, DvmDex* methodClassDex)
{
Method* absMethod;
Method* methodToCall;
int i, vtableIndex;
/*
* Resolve the method. This gives us the abstract method from the
* interface class declaration.
*/
absMethod = dvmDexGetResolvedMethod(methodClassDex, methodIdx);
if (absMethod == NULL) {
absMethod = dvmResolveInterfaceMethod(method->clazz, methodIdx);
if (absMethod == NULL) {
LOGV("+ unknown method\n");
return NULL;
}
}
/* make sure absMethod->methodIndex means what we think it means */
assert(dvmIsAbstractMethod(absMethod));
/*
* Run through the "this" object's iftable. Find the entry for
* absMethod's class, then use absMethod->methodIndex to find
* the method's entry. The value there is the offset into our
* vtable of the actual method to execute.
*
* The verifier does not guarantee that objects stored into
* interface references actually implement the interface, so this
* check cannot be eliminated.
*/
for (i = 0; i < thisClass->iftableCount; i++) {
if (thisClass->iftable[i].clazz == absMethod->clazz)
break;
}
if (i == thisClass->iftableCount) {
/* impossible in verified DEX, need to check for it in unverified */
dvmThrowIncompatibleClassChangeError("interface not implemented");
return NULL;
}
assert(absMethod->methodIndex <
thisClass->iftable[i].clazz->virtualMethodCount);
vtableIndex =
thisClass->iftable[i].methodIndexArray[absMethod->methodIndex];
assert(vtableIndex >= 0 && vtableIndex < thisClass->vtableCount);
methodToCall = thisClass->vtable[vtableIndex];
#if 0
/* this can happen when there's a stale class file */
if (dvmIsAbstractMethod(methodToCall)) {
dvmThrowAbstractMethodError("interface method not implemented");
return NULL;
}
#else
assert(!dvmIsAbstractMethod(methodToCall) ||
methodToCall->nativeFunc != NULL);
#endif
LOGVV("+++ interface=%s.%s concrete=%s.%s\n",
absMethod->clazz->descriptor, absMethod->name,
methodToCall->clazz->descriptor, methodToCall->name);
assert(methodToCall != NULL);
return methodToCall;
}
/*
* Helpers for dvmThrowVerificationError().
*
* Each returns a newly-allocated string.
*/
#define kThrowShow_accessFromClass 1
static char* classNameFromIndex(const Method* method, int ref,
VerifyErrorRefType refType, int flags)
{
static const int kBufLen = 256;
const DvmDex* pDvmDex = method->clazz->pDvmDex;
if (refType == VERIFY_ERROR_REF_FIELD) {
/* get class ID from field ID */
const DexFieldId* pFieldId = dexGetFieldId(pDvmDex->pDexFile, ref);
ref = pFieldId->classIdx;
} else if (refType == VERIFY_ERROR_REF_METHOD) {
/* get class ID from method ID */
const DexMethodId* pMethodId = dexGetMethodId(pDvmDex->pDexFile, ref);
ref = pMethodId->classIdx;
}
const char* className = dexStringByTypeIdx(pDvmDex->pDexFile, ref);
char* dotClassName = dvmHumanReadableDescriptor(className);
if (flags == 0)
return dotClassName;
char* result = (char*) malloc(kBufLen);
if ((flags & kThrowShow_accessFromClass) != 0) {
char* dotFromName =
dvmHumanReadableDescriptor(method->clazz->descriptor);
snprintf(result, kBufLen, "tried to access class %s from class %s",
dotClassName, dotFromName);
free(dotFromName);
} else {
assert(false); // should've been caught above
result[0] = '\0';
}
free(dotClassName);
return result;
}
static char* fieldNameFromIndex(const Method* method, int ref,
VerifyErrorRefType refType, int flags)
{
static const int kBufLen = 256;
const DvmDex* pDvmDex = method->clazz->pDvmDex;
const DexFieldId* pFieldId;
const char* className;
const char* fieldName;
if (refType != VERIFY_ERROR_REF_FIELD) {
LOGW("Expected ref type %d, got %d\n", VERIFY_ERROR_REF_FIELD, refType);
return NULL; /* no message */
}
pFieldId = dexGetFieldId(pDvmDex->pDexFile, ref);
className = dexStringByTypeIdx(pDvmDex->pDexFile, pFieldId->classIdx);
fieldName = dexStringById(pDvmDex->pDexFile, pFieldId->nameIdx);
char* dotName = dvmHumanReadableDescriptor(className);
char* result = (char*) malloc(kBufLen);
if ((flags & kThrowShow_accessFromClass) != 0) {
char* dotFromName =
dvmHumanReadableDescriptor(method->clazz->descriptor);
snprintf(result, kBufLen, "tried to access field %s.%s from class %s",
dotName, fieldName, dotFromName);
free(dotFromName);
} else {
snprintf(result, kBufLen, "%s.%s", dotName, fieldName);
}
free(dotName);
return result;
}
static char* methodNameFromIndex(const Method* method, int ref,
VerifyErrorRefType refType, int flags)
{
static const int kBufLen = 384;
const DvmDex* pDvmDex = method->clazz->pDvmDex;
const DexMethodId* pMethodId;
const char* className;
const char* methodName;
if (refType != VERIFY_ERROR_REF_METHOD) {
LOGW("Expected ref type %d, got %d\n", VERIFY_ERROR_REF_METHOD,refType);
return NULL; /* no message */
}
pMethodId = dexGetMethodId(pDvmDex->pDexFile, ref);
className = dexStringByTypeIdx(pDvmDex->pDexFile, pMethodId->classIdx);
methodName = dexStringById(pDvmDex->pDexFile, pMethodId->nameIdx);
char* dotName = dvmHumanReadableDescriptor(className);
char* result = (char*) malloc(kBufLen);
if ((flags & kThrowShow_accessFromClass) != 0) {
char* dotFromName =
dvmHumanReadableDescriptor(method->clazz->descriptor);
char* desc = dexProtoCopyMethodDescriptor(&method->prototype);
snprintf(result, kBufLen,
"tried to access method %s.%s:%s from class %s",
dotName, methodName, desc, dotFromName);
free(dotFromName);
free(desc);
} else {
snprintf(result, kBufLen, "%s.%s", dotName, methodName);
}
free(dotName);
return result;
}
/*
* Throw an exception for a problem identified by the verifier.
*
* This is used by the invoke-verification-error instruction. It always
* throws an exception.
*
* "kind" indicates the kind of failure encountered by the verifier. It
* has two parts, an error code and an indication of the reference type.
*/
void dvmThrowVerificationError(const Method* method, int kind, int ref)
{
const int typeMask = 0xff << kVerifyErrorRefTypeShift;
VerifyError errorKind = kind & ~typeMask;
VerifyErrorRefType refType = kind >> kVerifyErrorRefTypeShift;
ClassObject* exceptionClass = gDvm.exVerifyError;
char* msg = NULL;
switch ((VerifyError) errorKind) {
case VERIFY_ERROR_NO_CLASS:
exceptionClass = gDvm.exNoClassDefFoundError;
msg = classNameFromIndex(method, ref, refType, 0);
break;
case VERIFY_ERROR_NO_FIELD:
exceptionClass = gDvm.exNoSuchFieldError;
msg = fieldNameFromIndex(method, ref, refType, 0);
break;
case VERIFY_ERROR_NO_METHOD:
exceptionClass = gDvm.exNoSuchMethodError;
msg = methodNameFromIndex(method, ref, refType, 0);
break;
case VERIFY_ERROR_ACCESS_CLASS:
exceptionClass = gDvm.exIllegalAccessError;
msg = classNameFromIndex(method, ref, refType,
kThrowShow_accessFromClass);
break;
case VERIFY_ERROR_ACCESS_FIELD:
exceptionClass = gDvm.exIllegalAccessError;
msg = fieldNameFromIndex(method, ref, refType,
kThrowShow_accessFromClass);
break;
case VERIFY_ERROR_ACCESS_METHOD:
exceptionClass = gDvm.exIllegalAccessError;
msg = methodNameFromIndex(method, ref, refType,
kThrowShow_accessFromClass);
break;
case VERIFY_ERROR_CLASS_CHANGE:
exceptionClass = gDvm.exIncompatibleClassChangeError;
msg = classNameFromIndex(method, ref, refType, 0);
break;
case VERIFY_ERROR_INSTANTIATION:
exceptionClass = gDvm.exInstantiationError;
msg = classNameFromIndex(method, ref, refType, 0);
break;
case VERIFY_ERROR_GENERIC:
/* generic VerifyError; use default exception, no message */
break;
case VERIFY_ERROR_NONE:
/* should never happen; use default exception */
assert(false);
msg = strdup("weird - no error specified");
break;
/* no default clause -- want warning if enum updated */
}
dvmThrowException(exceptionClass, msg);
free(msg);
}
/*
* Update interpBreak. If there is an active break when
* we're done, set altHandlerTable. Otherwise, revert to
* the non-breaking table base.
*/
void dvmUpdateInterpBreak(Thread* thread, int newBreak, int newMode,
bool enable)
{
InterpBreak oldValue, newValue;
// Do not use this routine for suspend updates. See below.
assert((newBreak & kInterpSuspendBreak) == 0);
do {
oldValue = newValue = thread->interpBreak;
if (enable) {
newValue.ctl.breakFlags |= newBreak;
newValue.ctl.subMode |= newMode;
} else {
newValue.ctl.breakFlags &= ~newBreak;
newValue.ctl.subMode &= ~newMode;
}
newValue.ctl.curHandlerTable = (newValue.ctl.breakFlags) ?
thread->altHandlerTable : thread->mainHandlerTable;
} while (dvmQuasiAtomicCas64(oldValue.all, newValue.all,
&thread->interpBreak.all) != 0);
}
/*
* Update the normal and debugger suspend counts for a thread.
* threadSuspendCount must be acquired before calling this to
* ensure a clean update of suspendCount, dbgSuspendCount and
* sumThreadSuspendCount. suspendCount & dbgSuspendCount must
* use the atomic update to avoid conflict with writes to the
* other fields in interpBreak.
*
* CLEANUP TODO: Currently only the JIT is using sumThreadSuspendCount.
* Move under WITH_JIT ifdefs.
*/
void dvmAddToSuspendCounts(Thread* thread, int delta, int dbgDelta)
{
InterpBreak oldValue, newValue;
do {
oldValue = newValue = thread->interpBreak;
newValue.ctl.suspendCount += delta;
newValue.ctl.dbgSuspendCount += dbgDelta;
assert(newValue.ctl.suspendCount >= newValue.ctl.dbgSuspendCount);
if (newValue.ctl.suspendCount > 0) {
newValue.ctl.breakFlags |= kInterpSuspendBreak;
} else {
newValue.ctl.breakFlags &= ~kInterpSuspendBreak;
}
newValue.ctl.curHandlerTable = (newValue.ctl.breakFlags) ?
thread->altHandlerTable : thread->mainHandlerTable;
} while (dvmQuasiAtomicCas64(oldValue.all, newValue.all,
&thread->interpBreak.all) != 0);
// Update the global suspend count total
gDvm.sumThreadSuspendCount += delta;
}
/*
* Update interpBreak for all threads.
*/
void dvmUpdateAllInterpBreak(int newBreak, int newMode, bool enable)
{
Thread* self = dvmThreadSelf();
Thread* thread;
dvmLockThreadList(self);
for (thread = gDvm.threadList; thread != NULL; thread = thread->next) {
dvmUpdateInterpBreak(thread, newBreak, newMode, enable);
}
dvmUnlockThreadList();
}
/*
* One-time initialization at thread creation. Here we initialize
* useful constants.
*/
void dvmInitInterpreterState(Thread* self)
{
#if defined(WITH_JIT)
/* Interpreter entry points from compiled code */
extern void dvmJitToInterpNormal();
extern void dvmJitToInterpNoChain();
extern void dvmJitToInterpPunt();
extern void dvmJitToInterpSingleStep();
extern void dvmJitToInterpTraceSelect();
#if defined(WITH_SELF_VERIFICATION)
extern void dvmJitToInterpBackwardBranch();
#endif
/*
* Reserve a static entity here to quickly setup runtime contents as
* gcc will issue block copy instructions.
*/
static struct JitToInterpEntries jitToInterpEntries = {
dvmJitToInterpNormal,
dvmJitToInterpNoChain,
dvmJitToInterpPunt,
dvmJitToInterpSingleStep,
dvmJitToInterpTraceSelect,
#if defined(WITH_SELF_VERIFICATION)
dvmJitToInterpBackwardBranch,
#else
NULL,
#endif
};
#endif
// Begin initialization
self->cardTable = gDvm.biasedCardTableBase;
#if defined(WITH_JIT)
// One-time initializations
self->jitToInterpEntries = jitToInterpEntries;
self->icRechainCount = PREDICTED_CHAIN_COUNTER_RECHAIN;
self->pProfileCountdown = &gDvmJit.profileCountdown;
// Jit state that can change
dvmJitUpdateState();
#endif
}
/*
* Inter-instruction handler invoked in between instruction interpretations
* to handle exceptional events such as debugging housekeeping, instruction
* count profiling, JIT trace building, etc. Dalvik PC has been exported
* prior to call, but Thread copy of dPC & fp are not current.
*/
void dvmCheckBefore(const u2 *pc, const u4 *fp, Thread* self)
{
const Method* method = self->interpSave.method;
assert(self->interpBreak.ctl.breakFlags != 0);
assert(pc >= method->insns && pc <
method->insns + dvmGetMethodInsnsSize(method));
#if 0
/*
* When we hit a specific method, enable verbose instruction logging.
* Sometimes it's helpful to use the debugger attach as a trigger too.
*/
if (*pIsMethodEntry) {
static const char* cd = "Landroid/test/Arithmetic;";
static const char* mn = "shiftTest2";
static const char* sg = "()V";
if (/*self->interpBreak.ctl.subMode & kSubModeDebuggerActive &&*/
strcmp(method->clazz->descriptor, cd) == 0 &&
strcmp(method->name, mn) == 0 &&
strcmp(method->shorty, sg) == 0)
{
LOGW("Reached %s.%s, enabling verbose mode\n",
method->clazz->descriptor, method->name);
android_setMinPriority(LOG_TAG"i", ANDROID_LOG_VERBOSE);
dumpRegs(method, fp, true);
}
if (!gDvm.debuggerActive)
*pIsMethodEntry = false;
}
#endif
/* Suspend pending? */
if (self->interpBreak.ctl.suspendCount) {
// Neeeded for precise GC
dvmExportPC(pc, fp);
dvmCheckSuspendPending(self);
}
if (self->interpBreak.ctl.subMode & kSubModeDebuggerActive) {
dvmUpdateDebugger(method, pc, fp,
self->debugIsMethodEntry, self);
}
if (gDvm.instructionCountEnableCount != 0) {
/*
* Count up the #of executed instructions. This isn't synchronized
* for thread-safety; if we need that we should make this
* thread-local and merge counts into the global area when threads
* exit (perhaps suspending all other threads GC-style and pulling
* the data out of them).
*/
gDvm.executedInstrCounts[GET_OPCODE(*pc)]++;
}
#if defined(WITH_TRACKREF_CHECKS)
dvmInterpCheckTrackedRefs(self, method,
self->interpSave.debugTrackedRefStart);
#endif
#if defined(WITH_JIT)
// Does the JIT need anything done now?
if (self->interpBreak.ctl.breakFlags & kInterpJitBreak) {
// Are we building a trace?
if (self->interpBreak.ctl.subMode & kSubModeJitTraceBuild) {
dvmCheckJit(pc, self);
}
#if defined(WITH_SELF_VERIFICATION)
// Are we replaying a trace?
if (self->interpBreak.ctl.subMode & kSubModeJitSV) {
dvmCheckSelfVerification(pc, self);
}
#endif
}
#endif
/*
* SingleStep processing. NOTE: must be the last here to allow
* preceeding special case handler to manipulate single-step count.
*/
if (self->interpBreak.ctl.breakFlags & kInterpSingleStep) {
if (self->singleStepCount == 0) {
// We've exhausted our single step count
dvmUpdateInterpBreak(self, kInterpSingleStep, kSubModeNormal,
false /* remove */);
#if defined(WITH_JIT)
#if 0
/*
* For debugging. If jitResumeDPC is non-zero, then
* we expect to return to a trace in progress. There
* are valid reasons why we wouldn't (such as an exception
* throw), but here we can keep track.
*/
if (self->jitResumeDPC != NULL) {
if (self->jitResumeDPC == pc) {
if (self->jitResumeNPC != NULL) {
LOGD("SS return to trace - pc:0x%x to 0x:%x",
(int)pc, (int)self->jitResumeNPC);
} else {
LOGD("SS return to interp - pc:0x%x",(int)pc);
}
} else {
LOGD("SS failed to return. Expected 0x%x, now at 0x%x",
(int)self->jitResumeDPC, (int)pc);
}
}
#endif
// If we've got a native return and no other reasons to
// remain in singlestep/break mode, do a long jump
if (self->jitResumeNPC != NULL &&
self->interpBreak.ctl.breakFlags == 0) {
assert(self->jitResumeDPC == pc);
self->jitResumeDPC = NULL;
dvmJitResumeTranslation(self, pc, fp);
// Doesn't return
dvmAbort();
}
self->jitResumeDPC = NULL;
#endif
} else {
self->singleStepCount--;
#if defined(WITH_JIT)
if ((self->singleStepCount > 0) && (self->jitResumeNPC != NULL)) {
/*
* Direct return to an existing translation following a
* single step is valid only if we step once. If we're
* here, an additional step was added so we need to invalidate
* the return to translation.
*/
self->jitResumeNPC = NULL;
}
#endif
}
}
}
/*
* Main interpreter loop entry point.
*
* This begins executing code at the start of "method". On exit, "pResult"
* holds the return value of the method (or, if "method" returns NULL, it
* holds an undefined value).
*
* The interpreted stack frame, which holds the method arguments, has
* already been set up.
*/
void dvmInterpret(Thread* self, const Method* method, JValue* pResult)
{
InterpSaveState interpSaveState;
int savedBreakFlags;
int savedSubModes;
#if defined(WITH_JIT)
/* Target-specific save/restore */
extern void dvmJitCalleeSave(double *saveArea);
extern void dvmJitCalleeRestore(double *saveArea);
double calleeSave[JIT_CALLEE_SAVE_DOUBLE_COUNT];
/*
* If the previous VM left the code cache through single-stepping the
* inJitCodeCache flag will be set when the VM is re-entered (for example,
* in self-verification mode we single-step NEW_INSTANCE which may re-enter
* the VM through findClassFromLoaderNoInit). Because of that, we cannot
* assert that self->inJitCodeCache is NULL here.
*/
#endif
/*
* Save interpreter state from previous activation, linking
* new to last.
*/
interpSaveState = self->interpSave;
self->interpSave.prev = &interpSaveState;
/*
* Strip out and save any flags that should not be inherited by
* nested interpreter activation.
*/
savedBreakFlags = self->interpBreak.ctl.breakFlags & LOCAL_BREAKFLAGS;
savedSubModes = self->interpBreak.ctl.subMode & LOCAL_SUBMODE;
if (savedBreakFlags | savedSubModes) {
dvmUpdateInterpBreak(self, savedBreakFlags, savedSubModes,
false /*disable*/);
}
#if defined(WITH_JIT)
dvmJitCalleeSave(calleeSave);
#endif
#if defined(WITH_TRACKREF_CHECKS)
self->interpSave.debugTrackedRefStart =
dvmReferenceTableEntries(&self->internalLocalRefTable);
#endif
self->debugIsMethodEntry = true;
#if defined(WITH_JIT)
dvmJitCalleeSave(calleeSave);
/* Initialize the state to kJitNot */
self->jitState = kJitNot;
#endif
/*
* Initialize working state.
*
* No need to initialize "retval".
*/
self->interpSave.method = method;
self->interpSave.fp = (u4*) self->curFrame;
self->interpSave.pc = method->insns;
assert(!dvmIsNativeMethod(method));
/*
* Make sure the class is ready to go. Shouldn't be possible to get
* here otherwise.
*/
if (method->clazz->status < CLASS_INITIALIZING ||
method->clazz->status == CLASS_ERROR)
{
LOGE("ERROR: tried to execute code in unprepared class '%s' (%d)\n",
method->clazz->descriptor, method->clazz->status);
dvmDumpThread(self, false);
dvmAbort();
}
typedef void (*Interpreter)(Thread*);
Interpreter stdInterp;
if (gDvm.executionMode == kExecutionModeInterpFast)
stdInterp = dvmMterpStd;
#if defined(WITH_JIT)
else if (gDvm.executionMode == kExecutionModeJit)
stdInterp = dvmMterpStd;
#endif
else
stdInterp = dvmInterpretPortable;
// Call the interpreter
(*stdInterp)(self);
*pResult = self->retval;
/* Restore interpreter state from previous activation */
self->interpSave = interpSaveState;
#if defined(WITH_JIT)
dvmJitCalleeRestore(calleeSave);
#endif
if (savedBreakFlags | savedSubModes) {
dvmUpdateInterpBreak(self, savedBreakFlags, savedSubModes,
true /*enable*/);
}
}