/*
* Rebuild the interpreter frame then punt to the interpreter to execute
* instruction at specified PC.
*
* Currently parameters are passed to the current frame, so we just need to
* grow the stack save area above it, fill certain fields in StackSaveArea and
* Thread that are skipped during whole-method invocation (specified below),
* then return to the interpreter.
*
* StackSaveArea:
* - prevSave
* - prevFrame
* - savedPc
* - returnAddr
* - method
*
* Thread:
* - method
* - methodClassDex
* - curFrame
*/
static void genMethodInflateAndPunt(CompilationUnit *cUnit, MIR *mir,
BasicBlock *bb)
{
int oldStackSave = r0;
int newStackSave = r1;
int oldFP = r2;
int savedPC = r3;
int currentPC = r4PC;
int returnAddr = r7;
int method = r8;
int pDvmDex = r9;
/*
* TODO: check whether to raise the stack overflow exception when growing
* the stack save area.
*/
/* Send everything to home location */
dvmCompilerFlushAllRegs(cUnit);
/* oldStackSave = r5FP + sizeof(current frame) */
opRegRegImm(cUnit, kOpAdd, oldStackSave, r5FP,
cUnit->method->registersSize * 4);
/* oldFP = oldStackSave + sizeof(stackSaveArea) */
opRegRegImm(cUnit, kOpAdd, oldFP, oldStackSave, sizeof(StackSaveArea));
/* newStackSave = r5FP - sizeof(StackSaveArea) */
opRegRegImm(cUnit, kOpSub, newStackSave, r5FP, sizeof(StackSaveArea));
loadWordDisp(cUnit, r13sp, 0, savedPC);
loadConstant(cUnit, currentPC, (int) (cUnit->method->insns + mir->offset));
loadConstant(cUnit, method, (int) cUnit->method);
loadConstant(cUnit, pDvmDex, (int) cUnit->method->clazz->pDvmDex);
#ifdef EASY_GDB
/* newStackSave->prevSave = oldStackSave */
storeWordDisp(cUnit, newStackSave, offsetof(StackSaveArea, prevSave),
oldStackSave);
#endif
/* newStackSave->prevSave = oldStackSave */
storeWordDisp(cUnit, newStackSave, offsetof(StackSaveArea, prevFrame),
oldFP);
/* newStackSave->savedPc = savedPC */
storeWordDisp(cUnit, newStackSave, offsetof(StackSaveArea, savedPc),
savedPC);
/* return address */
loadConstant(cUnit, returnAddr, 0);
storeWordDisp(cUnit, newStackSave, offsetof(StackSaveArea, returnAddr),
returnAddr);
/* newStackSave->method = method */
storeWordDisp(cUnit, newStackSave, offsetof(StackSaveArea, method), method);
/* thread->method = method */
storeWordDisp(cUnit, r6SELF, offsetof(InterpSaveState, method), method);
/* thread->interpSave.curFrame = current FP */
storeWordDisp(cUnit, r6SELF, offsetof(Thread, interpSave.curFrame), r5FP);
/* thread->methodClassDex = pDvmDex */
storeWordDisp(cUnit, r6SELF, offsetof(InterpSaveState, methodClassDex),
pDvmDex);
/* Restore the stack pointer */
opRegImm(cUnit, kOpAdd, r13sp, 16);
genPuntToInterp(cUnit, mir->offset);
}
static void genInterpSingleStep(CompilationUnit *cUnit, MIR *mir)
{
int flags = dexGetFlagsFromOpcode(mir->dalvikInsn.opcode);
int flagsToCheck = kInstrCanBranch | kInstrCanSwitch | kInstrCanReturn |
kInstrCanThrow;
//If already optimized out, just ignore
if (mir->dalvikInsn.opcode == OP_NOP)
return;
//Ugly, but necessary. Flush all Dalvik regs so Interp can find them
dvmCompilerFlushAllRegs(cUnit);
if ((mir->next == NULL) || (flags & flagsToCheck)) {
genPuntToInterp(cUnit, mir->offset);
return;
}
int entryAddr = offsetof(Thread,
jitToInterpEntries.dvmJitToInterpSingleStep);
loadWordDisp(cUnit, rEBP, 0, rECX); // Get glue
loadWordDisp(cUnit, rECX, entryAddr, rEAX); // rEAX<- entry address
/* rPC = dalvik pc */
loadConstant(cUnit, rPC, (int) (cUnit->method->insns + mir->offset));
/* rECX = dalvik pc of following instruction */
loadConstant(cUnit, rECX, (int) (cUnit->method->insns + mir->next->offset));
/* Pass on the stack */
storeWordDisp(cUnit, rESP, OUT_ARG0, rECX);
opReg(cUnit, kOpCall, rEAX);
}