2522 Node* address = in(MemNode::Address);
2523 // Back-to-back stores to same address? Fold em up. Generally
2524 // unsafe if I have intervening uses... Also disallowed for StoreCM
2525 // since they must follow each StoreP operation. Redundant StoreCMs
2526 // are eliminated just before matching in final_graph_reshape.
2527 {
2528 Node* st = mem;
2529 // If Store 'st' has more than one use, we cannot fold 'st' away.
2530 // For example, 'st' might be the final state at a conditional
2531 // return. Or, 'st' might be used by some node which is live at
2532 // the same time 'st' is live, which might be unschedulable. So,
2533 // require exactly ONE user until such time as we clone 'mem' for
2534 // each of 'mem's uses (thus making the exactly-1-user-rule hold
2535 // true).
2536 while (st->is_Store() && st->outcnt() == 1 && st->Opcode() != Op_StoreCM) {
2537 // Looking at a dead closed cycle of memory?
2538 assert(st != st->in(MemNode::Memory), "dead loop in StoreNode::Ideal");
2539 assert(Opcode() == st->Opcode() ||
2540 st->Opcode() == Op_StoreVector ||
2541 Opcode() == Op_StoreVector ||
2542 phase->C->get_alias_index(adr_type()) == Compile::AliasIdxRaw ||
2543 (Opcode() == Op_StoreL && st->Opcode() == Op_StoreI) || // expanded ClearArrayNode
2544 (Opcode() == Op_StoreI && st->Opcode() == Op_StoreL) || // initialization by arraycopy
2545 (is_mismatched_access() || st->as_Store()->is_mismatched_access()),
2546 "no mismatched stores, except on raw memory: %s %s", NodeClassNames[Opcode()], NodeClassNames[st->Opcode()]);
2547
2548 if (st->in(MemNode::Address)->eqv_uncast(address) &&
2549 st->as_Store()->memory_size() <= this->memory_size()) {
2550 Node* use = st->raw_out(0);
2551 phase->igvn_rehash_node_delayed(use);
2552 if (can_reshape) {
2553 use->set_req_X(MemNode::Memory, st->in(MemNode::Memory), phase->is_IterGVN());
2554 } else {
2555 // It's OK to do this in the parser, since DU info is always accurate,
2556 // and the parser always refers to nodes via SafePointNode maps.
2557 use->set_req(MemNode::Memory, st->in(MemNode::Memory));
2558 }
2559 return this;
2560 }
2561 st = st->in(MemNode::Memory);
|
2522 Node* address = in(MemNode::Address);
2523 // Back-to-back stores to same address? Fold em up. Generally
2524 // unsafe if I have intervening uses... Also disallowed for StoreCM
2525 // since they must follow each StoreP operation. Redundant StoreCMs
2526 // are eliminated just before matching in final_graph_reshape.
2527 {
2528 Node* st = mem;
2529 // If Store 'st' has more than one use, we cannot fold 'st' away.
2530 // For example, 'st' might be the final state at a conditional
2531 // return. Or, 'st' might be used by some node which is live at
2532 // the same time 'st' is live, which might be unschedulable. So,
2533 // require exactly ONE user until such time as we clone 'mem' for
2534 // each of 'mem's uses (thus making the exactly-1-user-rule hold
2535 // true).
2536 while (st->is_Store() && st->outcnt() == 1 && st->Opcode() != Op_StoreCM) {
2537 // Looking at a dead closed cycle of memory?
2538 assert(st != st->in(MemNode::Memory), "dead loop in StoreNode::Ideal");
2539 assert(Opcode() == st->Opcode() ||
2540 st->Opcode() == Op_StoreVector ||
2541 Opcode() == Op_StoreVector ||
2542 st->Opcode() == Op_StoreVectorScatter ||
2543 Opcode() == Op_StoreVectorScatter ||
2544 phase->C->get_alias_index(adr_type()) == Compile::AliasIdxRaw ||
2545 (Opcode() == Op_StoreL && st->Opcode() == Op_StoreI) || // expanded ClearArrayNode
2546 (Opcode() == Op_StoreI && st->Opcode() == Op_StoreL) || // initialization by arraycopy
2547 (is_mismatched_access() || st->as_Store()->is_mismatched_access()),
2548 "no mismatched stores, except on raw memory: %s %s", NodeClassNames[Opcode()], NodeClassNames[st->Opcode()]);
2549
2550 if (st->in(MemNode::Address)->eqv_uncast(address) &&
2551 st->as_Store()->memory_size() <= this->memory_size()) {
2552 Node* use = st->raw_out(0);
2553 phase->igvn_rehash_node_delayed(use);
2554 if (can_reshape) {
2555 use->set_req_X(MemNode::Memory, st->in(MemNode::Memory), phase->is_IterGVN());
2556 } else {
2557 // It's OK to do this in the parser, since DU info is always accurate,
2558 // and the parser always refers to nodes via SafePointNode maps.
2559 use->set_req(MemNode::Memory, st->in(MemNode::Memory));
2560 }
2561 return this;
2562 }
2563 st = st->in(MemNode::Memory);
|