lookupTarget* sicScopeLookupTarget::get_target_for_slot(slotDesc* s,
simpleLookup* L) {
Unused(L);
if (s->name == VMString[LEXICAL_PARENT]) {
return new sicScopeLookupTarget(scope->parent());
} else if (s->name == VMString[SELF]) {
SExpr* t = scope->receiverExpr();
if (t->isConstantSExpr()) {
return (new objectLookupTarget(t->constant())) -> be_receiver();
} else if (t->hasMap()) {
return ( new mapLookupTarget(t->map())) -> be_receiver();
} else {
// don't know the receiver type
return NULL;
}
} else if (! s->is_map_slot()) {
return NULL;
} else {
return new objectLookupTarget(s->data);
}
}
SExpr* SPrimScope::inlineIntArithmetic() {
ArithOpCode op = opcode_for_selector(_selector);
bool intRcvr =
receiver->hasMap() && receiver->map() == Memory->smi_map;
SExpr* arg = args->nth(0);
bool intArg = arg->hasMap() && arg->map() == Memory->smi_map;
if ( intArg
&& arg->isConstantSExpr()
&& intRcvr
&& arg->constant() == as_smiOop(0)
&& can_fold_rcvr_op_zero_to_zero(op)) {
if (PrintInlining)
lprintf("%*s*constant-folding %s: 0\n", (void*)(depth-1), "", ArithOpName[op]);
return receiver;
}
if (PrintInlining) lprintf("%*s*inlining %s:\n", (void*)(depth-1),
"", ArithOpName[op]);
if (!TArithRRNode::isOpInlinable(op))
return NULL;
NodeGen* n = theNodeGen;
Node* arith = n->append(new TArithRRNode(op, receiver->preg(), arg->preg(),
resultPR, intRcvr, intArg));
// success case - no overflow, int tags
MergeNode* ok = (MergeNode*)n->append(new MergeNode("inlineIntArithmetic ok"));
SExpr* succExpr = new MapSExpr(Memory->smi_map->enclosing_mapOop(), resultPR, ok);
// merge of success & failure branches
MergeNode* done = (MergeNode*)ok->append(new MergeNode("inlineIntArithmetic done"));
// failure case
n->current = arith->append1(new NopNode);
if (theSIC->useUncommonTraps &&
sender()->rscope->isUncommonAt(sender()->bci(), true)) {
n->uncommonBranch(currentExprStack(0), true);
n->current = done;
if (PrintInlining) {
lprintf("%*s*making arithmetic failure uncommon\n", (void*)(depth-1),
"");
}
return succExpr;
} else {
fint b = bci();
PReg* error = new SAPReg(_sender, b, b);
if (intRcvr && intArg) {
// must be overflow
n->loadOop(VMString[OVERFLOWERROR], error);
} else {
arith->hasSideEffects_now = true; // may fail, so can't eliminate
if (intRcvr || TARGET_ARCH == I386_ARCH) {
// arg & TagMask already done by TArithRRNode
// I386 does 'em all
} else {
PReg* t = new TempPReg(this, Temp1, false, true);
n->append(new ArithRCNode(AndCCArithOp, t, Tag_Mask, t));
n->current->hasSideEffects_now = true;
}
// Note: this code assumes that condcode EQ means overflow
Node* branch = n->append(new BranchNode(EQBranchOp));
// no overflow, must be type error
n->loadOop(VMString[BADTYPEERROR], error);
MergeNode* cont = (MergeNode*)n->append(
new MergeNode("inlineIntArithmetic cont"));
// overflow error
PReg* err = new_ConstPReg(_sender, VMString[OVERFLOWERROR]);
n->current = branch->append1(new AssignNode(err, error));
n->branch(cont);
}
Node* dummy;
SExpr* failExpr = genPrimFailure(NULL, error, dummy, done, resultPR);
assert(done, "merge should always exist");
return succExpr->mergeWith(failExpr, done);
}
}
const char* NodeGen::splitCondBranch( MergeNode* targetNode,
bool isBackwards,
PReg* targetPR,
SExpr* testExpr,
BranchBCTargetStack* targetStack,
SExprStack* exprStack,
PRegBList* exprStackPRs,
SplitSig* s ) {
// try to split a conditional branch bc to avoid materializing
// the boolean
// local splitting only for now
assert(targetPR->isConstPReg(),
"cond branch must be testing for constant");
oop targetOop = ((ConstPReg*)targetPR)->constant;
if (!testExpr->isMergeSExpr())
return "testExpr not MergeSExpr";
if (!((MergeSExpr*)testExpr)->isSplittable())
return "textExpr not splittable";
SExprBList* exprs = ((MergeSExpr*)testExpr)->exprs;
assert(testExpr->node(), "splittable implies node()");
Node* preceedingMerge = testExpr->node();
if (current != preceedingMerge)
return "not local"; // local only for now
if ( preceedingMerge->nPredecessors() != exprs->length() )
return "would have to iterate over predecessors";
fint i;
for ( i = 0;
i < exprs->length();
++i) {
SExpr* e = exprs->nth(i);
Node* n = e->node();
if ( !preceedingMerge->isPredecessor(n) )
return "merge not immediately after expr node";
if ( !e->isConstantSExpr() )
return "merge contains non-constant expression";
}
MergeNode* mergeForBranching = new MergeNode("for branching");
MergeNode* mergeForFallingThrough = new MergeNode("for falling through");
mergeForBranching ->setScope(currentScope());
mergeForFallingThrough->setScope(currentScope());
for ( i = 0;
i < exprs->length();
++i) {
SExpr* e = exprs->nth(i);
Node* n = e->node();
MergeNode* mn = e->constant() == targetOop
? mergeForBranching
: mergeForFallingThrough;
mn->setPrev(n);
n->moveNext(preceedingMerge, mn);
}
while (preceedingMerge->nPredecessors())
preceedingMerge->removePrev(preceedingMerge->prev(0));
current = mergeForBranching;
branchCode( targetNode,
isBackwards,
NULL,
NULL,
targetStack,
exprStack,
exprStackPRs,
s);
append(mergeForFallingThrough);
return NULL;
}
SExpr* SCodeScope::inlineMerge(SendInfo* info, MergeNode*& merge) {
// inline the send by type-casing; return uninlined cases in others list
// If merge has no predecessors, return NULL for merge ref.
SExpr* res = NULL;
assert(info->rcvr->isMergeSExpr(), "must be a merge");
MergeSExpr* r = (MergeSExpr*)info->rcvr;
stringOop sel = info->sel;
merge = NULL;
if (r->isSplittable() && shouldSplit(info)) {
return splitMerge(info, merge);
}
fint ncases = r->exprs->length();
if (ncases > SICTypeCaseLimit) {
info->needRealSend = true;
if (PrintInlining) {
lprintf("%*s*not type-casing %s (%ld > SICTypeCaseLimit)\n",
(void*)depth, "", selector_string(sel), (void*)ncases);
}
return res;
}
assert( merge == NULL, "I assume merge is out param only");
merge = new MergeNode("inlineMerge merge");
if (SICDebug) {
char* s = NEW_RESOURCE_ARRAY(char, 200);
sprintf(s, "begin type-case of %s (ends at node N%ld)",
sel->copy_null_terminated(), long(merge->id()));
theNodeGen->comment(s);
}
if (PrintInlining) {
lprintf("%*s*type-casing %s\n", (void*)depth, "", selector_string(sel));
}
// build list of cases to inline
// (add only immediate maps at first, collect others in ...2 lists
SSelfScopeBList* slist = new SSelfScopeBList(ncases);
SSelfScopeBList* slist2 = new SSelfScopeBList(ncases);
SExprBList* elist = new SExprBList(ncases);
SExprBList* elist2 = new SExprBList(ncases);
SExprBList* others = new SExprBList(ncases);
OopBList* mlist = new OopBList(ncases);
OopBList* mlist2 = new OopBList(ncases);
bool needMapLoad = false;
fint i;
for (i = 0; i < ncases; i++) {
SExpr* nth = r->exprs->nth(i);
assert(!nth->isConstantSExpr() || nth->next == NULL ||
nth->constant() == nth->next->constant(),
"shouldn't happen: merged consts - convert to map");
SSelfScope* s;
if (!nth->hasMap() || (s = tryLookup(info, nth)) == NULL) {
// cannot inline
others->append(nth);
info->needRealSend = true;
continue;
}
// can inline this case
// Notice that for immediates, instead of putting the constants in the mlist,
// we put the maps. No point in optimizing just for 17. -- dmu 6/05
Map* map = nth->map();
if (map == Memory->smi_map || map == Memory->float_map) {
slist ->append(s); // immediate maps go first
// Bug fix: instead of nth->shallowCopy, must generalize to any
// with same map, not just the same constant, because other ints (for example)
// will pass the type test, too. -- dmu 6/05
elist ->append(new MapSExpr(map->enclosing_mapOop(), r->preg(), NULL));
mlist ->append(map->enclosing_mapOop());
continue;
}
// can inline but not immediate map
slist2->append(s); // append later
elist2->append(nth->shallowCopy(r->preg(), NULL)); // use preg of merge
if (nth->isConstantSExpr()) {
mlist2->append(nth->constant());
}
else {
needMapLoad = true; // will need to load map of testee
mlist2->append(map->enclosing_mapOop());
}
}
mlist->appendList(mlist2);
elist->appendList(elist2);
slist->appendList(slist2);
// now do the type test and inline the individual cases
if (slist->length() > 0) {
memoizeBlocks(sel);
Node* typeCase =
theNodeGen->append(new TypeTestNode(r->preg(), mlist, needMapLoad,
info->needRealSend));
Node* fallThrough = typeCase->append(new NopNode);
for (i = 0; i < slist->length(); i++) {
theNodeGen->current = typeCase->append(i + 1, new NopNode);
SExpr* e = doInline(slist->nth(i), elist->nth(i), theNodeGen->current, merge);
if (!e->isNoResultSExpr()) {
theNodeGen->append(new NopNode);
e = e->shallowCopy(info->resReg, theNodeGen->current);
res = res ? res->mergeWith(e, merge) : e;
}
theNodeGen->branch(merge);
}
theNodeGen->current = fallThrough;
}
if (res && res->isMergeSExpr())
res->setNode(merge, info->resReg);
assert( info->needRealSend && others->length() ||
!info->needRealSend && !others->length(), "inconsistent");
// NB: *must* use uncommon branch if marked unlikely because
// future type tests won't test for unknown
if (others->isEmpty()) {
// typecase cannot fail
theNodeGen->deadEnd();
}
else if ( others->length() == 1
&& others->first()->isUnknownSExpr()
&& ((UnknownSExpr*)others->first())->isUnlikely()) {
// generate an uncommon branch for the unknown case, not a send
theNodeGen->uncommonBranch(currentExprStack(0), info->restartPrim);
info->needRealSend = false;
if (PrintInlining)
lprintf("%*s*making %s uncommon (2)\n", (void*)depth,"",selector_string(sel));
}
return res;
}
SExpr* SCodeScope::picPredict(SendInfo* info) {
// check PICs for information
if (!UsePICRecompilation) return info->rcvr;
bool canBeUnlikely = theSIC->useUncommonTraps;
if (rscope->hasSubScopes(_bci)) {
RScopeBList* l = rscope->subScopes(_bci);
if (l->first()->isUntakenScope() && l->length() == 1) {
return picPredictUnlikely(info, (RUntakenScope*)l->first());
} else if (info->rcvr->containsUnknown()) {
if (PrintInlining) {
lprintf("%*s*PIC-type-predicting %s (%ld maps)\n", (void*)depth, "",
info->sel->copy_null_terminated(), (void*)l->length());
}
for (fint i = 0; i < l->length(); i++) {
RScope* r = l->nth(i);
SExpr* expr = r->receiverExpr();
if (expr->isUnknownSExpr()) {
// untaken real send (from PIC)
} else if (expr->map()->is_block()) {
// for now, doesn't make sense to predict block maps because of
// map cloning
if (PrintInlining) {
lprintf("%*s*not predicting block map\n", (void*)depth, "");
}
canBeUnlikely = false;
} else {
SExpr* alreadyThere = info->rcvr->findMap(expr->myMapOop());
if (alreadyThere) {
// generalize to map if only have constant
if (alreadyThere->isConstantSExpr())
info->rcvr = info->rcvr->mergeWith(expr, NULL);
} else {
// add map only if type isn't already present (for splitting)
info->predicted = true;
info->rcvr = info->rcvr->mergeWith(expr, NULL);
if (expr->hasConstant() && l->length() == 1) {
// check to see if single predicted receiver is true or false;
// if so, add other boolean to prediction. Reduces the number
// of uncommon branches; not doing so appears to be overly
// aggressive (as observed experimentally)
oop c = expr->constant();
if (c == Memory->trueObj &&
!info->rcvr->findMap(Memory->false_mapOop())) {
SExpr* f = new ConstantSExpr(Memory->falseObj, NULL, NULL);
info->rcvr = info->rcvr->mergeWith(f, NULL);
} else if (c == Memory->falseObj &&
!info->rcvr->findMap(Memory->true_mapOop())) {
SExpr* t = new ConstantSExpr(Memory->trueObj, NULL, NULL);
info->rcvr = info->rcvr->mergeWith(t, NULL);
}
}
}
}
}
} else {
// know receiver type precisely
return info->rcvr;
}
// mark unknown branch as unlikely
UnknownSExpr* u = info->rcvr->findUnknown();
if (u && canBeUnlikely && theSIC->useUncommonTraps &&
rscope->isUncommonAt(_bci, false)) {
info->rcvr = info->rcvr->makeUnknownUnlikely(this);
}
} else if (theSIC->useUncommonTraps &&
info->primFailure &&
rscope->isUncommonAt(_bci, true)) {
// this is the failure send of a primitive, and the failure was made
// uncommon in the recompilee, and it was never taken, so keep it
// uncommon
if (PrintInlining) {
lprintf("%*s*PIC-type-predicting %s as never executed (2)\n",
(void*)depth, "", info->sel->copy_null_terminated());
}
info->rcvr = new UnknownSExpr(info->rcvr->preg(), NULL, true);
}
assert(info->rcvr->preg(), "should have a preg");
return info->rcvr;
}
