/* * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include "precompiled.hpp" #include "libadt/vectset.hpp" #include "memory/allocation.inline.hpp" #include "opto/cfgnode.hpp" #include "opto/connode.hpp" #include "opto/loopnode.hpp" #include "opto/machnode.hpp" #include "opto/matcher.hpp" #include "opto/node.hpp" #include "opto/opcodes.hpp" #include "opto/regmask.hpp" #include "opto/type.hpp" #include "utilities/copy.hpp" class RegMask; // #include "phase.hpp" class PhaseTransform; class PhaseGVN; // Arena we are currently building Nodes in const uint Node::NotAMachineReg = 0xffff0000; #ifndef PRODUCT extern int nodes_created; #endif #ifdef ASSERT //-------------------------- construct_node------------------------------------ // Set a breakpoint here to identify where a particular node index is built. void Node::verify_construction() { _debug_orig = NULL; int old_debug_idx = Compile::debug_idx(); int new_debug_idx = old_debug_idx+1; if (new_debug_idx > 0) { // Arrange that the lowest five decimal digits of _debug_idx // will repeat those of _idx. In case this is somehow pathological, // we continue to assign negative numbers (!) consecutively. const int mod = 100000; int bump = (int)(_idx - new_debug_idx) % mod; if (bump < 0) bump += mod; assert(bump >= 0 && bump < mod, ""); new_debug_idx += bump; } Compile::set_debug_idx(new_debug_idx); set_debug_idx( new_debug_idx ); assert(Compile::current()->unique() < (INT_MAX - 1), "Node limit exceeded INT_MAX"); assert(Compile::current()->live_nodes() < Compile::current()->max_node_limit(), "Live Node limit exceeded limit"); if (BreakAtNode != 0 && (_debug_idx == BreakAtNode || (int)_idx == BreakAtNode)) { tty->print_cr("BreakAtNode: _idx=%d _debug_idx=%d", _idx, _debug_idx); BREAKPOINT; } #if OPTO_DU_ITERATOR_ASSERT _last_del = NULL; _del_tick = 0; #endif _hash_lock = 0; } // #ifdef ASSERT ... #if OPTO_DU_ITERATOR_ASSERT void DUIterator_Common::sample(const Node* node) { _vdui = VerifyDUIterators; _node = node; _outcnt = node->_outcnt; _del_tick = node->_del_tick; _last = NULL; } void DUIterator_Common::verify(const Node* node, bool at_end_ok) { assert(_node == node, "consistent iterator source"); assert(_del_tick == node->_del_tick, "no unexpected deletions allowed"); } void DUIterator_Common::verify_resync() { // Ensure that the loop body has just deleted the last guy produced. const Node* node = _node; // Ensure that at least one copy of the last-seen edge was deleted. // Note: It is OK to delete multiple copies of the last-seen edge. // Unfortunately, we have no way to verify that all the deletions delete // that same edge. On this point we must use the Honor System. assert(node->_del_tick >= _del_tick+1, "must have deleted an edge"); assert(node->_last_del == _last, "must have deleted the edge just produced"); // We liked this deletion, so accept the resulting outcnt and tick. _outcnt = node->_outcnt; _del_tick = node->_del_tick; } void DUIterator_Common::reset(const DUIterator_Common& that) { if (this == &that) return; // ignore assignment to self if (!_vdui) { // We need to initialize everything, overwriting garbage values. _last = that._last; _vdui = that._vdui; } // Note: It is legal (though odd) for an iterator over some node x // to be reassigned to iterate over another node y. Some doubly-nested // progress loops depend on being able to do this. const Node* node = that._node; // Re-initialize everything, except _last. _node = node; _outcnt = node->_outcnt; _del_tick = node->_del_tick; } void DUIterator::sample(const Node* node) { DUIterator_Common::sample(node); // Initialize the assertion data. _refresh_tick = 0; // No refreshes have happened, as yet. } void DUIterator::verify(const Node* node, bool at_end_ok) { DUIterator_Common::verify(node, at_end_ok); assert(_idx < node->_outcnt + (uint)at_end_ok, "idx in range"); } void DUIterator::verify_increment() { if (_refresh_tick & 1) { // We have refreshed the index during this loop. // Fix up _idx to meet asserts. if (_idx > _outcnt) _idx = _outcnt; } verify(_node, true); } void DUIterator::verify_resync() { // Note: We do not assert on _outcnt, because insertions are OK here. DUIterator_Common::verify_resync(); // Make sure we are still in sync, possibly with no more out-edges: verify(_node, true); } void DUIterator::reset(const DUIterator& that) { if (this == &that) return; // self assignment is always a no-op assert(that._refresh_tick == 0, "assign only the result of Node::outs()"); assert(that._idx == 0, "assign only the result of Node::outs()"); assert(_idx == that._idx, "already assigned _idx"); if (!_vdui) { // We need to initialize everything, overwriting garbage values. sample(that._node); } else { DUIterator_Common::reset(that); if (_refresh_tick & 1) { _refresh_tick++; // Clear the "was refreshed" flag. } assert(_refresh_tick < 2*100000, "DU iteration must converge quickly"); } } void DUIterator::refresh() { DUIterator_Common::sample(_node); // Re-fetch assertion data. _refresh_tick |= 1; // Set the "was refreshed" flag. } void DUIterator::verify_finish() { // If the loop has killed the node, do not require it to re-run. if (_node->_outcnt == 0) _refresh_tick &= ~1; // If this assert triggers, it means that a loop used refresh_out_pos // to re-synch an iteration index, but the loop did not correctly // re-run itself, using a "while (progress)" construct. // This iterator enforces the rule that you must keep trying the loop // until it "runs clean" without any need for refreshing. assert(!(_refresh_tick & 1), "the loop must run once with no refreshing"); } void DUIterator_Fast::verify(const Node* node, bool at_end_ok) { DUIterator_Common::verify(node, at_end_ok); Node** out = node->_out; uint cnt = node->_outcnt; assert(cnt == _outcnt, "no insertions allowed"); assert(_outp >= out && _outp <= out + cnt - !at_end_ok, "outp in range"); // This last check is carefully designed to work for NO_OUT_ARRAY. } void DUIterator_Fast::verify_limit() { const Node* node = _node; verify(node, true); assert(_outp == node->_out + node->_outcnt, "limit still correct"); } void DUIterator_Fast::verify_resync() { const Node* node = _node; if (_outp == node->_out + _outcnt) { // Note that the limit imax, not the pointer i, gets updated with the // exact count of deletions. (For the pointer it's always "--i".) assert(node->_outcnt+node->_del_tick == _outcnt+_del_tick, "no insertions allowed with deletion(s)"); // This is a limit pointer, with a name like "imax". // Fudge the _last field so that the common assert will be happy. _last = (Node*) node->_last_del; DUIterator_Common::verify_resync(); } else { assert(node->_outcnt < _outcnt, "no insertions allowed with deletion(s)"); // A normal internal pointer. DUIterator_Common::verify_resync(); // Make sure we are still in sync, possibly with no more out-edges: verify(node, true); } } void DUIterator_Fast::verify_relimit(uint n) { const Node* node = _node; assert((int)n > 0, "use imax -= n only with a positive count"); // This must be a limit pointer, with a name like "imax". assert(_outp == node->_out + node->_outcnt, "apply -= only to a limit (imax)"); // The reported number of deletions must match what the node saw. assert(node->_del_tick == _del_tick + n, "must have deleted n edges"); // Fudge the _last field so that the common assert will be happy. _last = (Node*) node->_last_del; DUIterator_Common::verify_resync(); } void DUIterator_Fast::reset(const DUIterator_Fast& that) { assert(_outp == that._outp, "already assigned _outp"); DUIterator_Common::reset(that); } void DUIterator_Last::verify(const Node* node, bool at_end_ok) { // at_end_ok means the _outp is allowed to underflow by 1 _outp += at_end_ok; DUIterator_Fast::verify(node, at_end_ok); // check _del_tick, etc. _outp -= at_end_ok; assert(_outp == (node->_out + node->_outcnt) - 1, "pointer must point to end of nodes"); } void DUIterator_Last::verify_limit() { // Do not require the limit address to be resynched. //verify(node, true); assert(_outp == _node->_out, "limit still correct"); } void DUIterator_Last::verify_step(uint num_edges) { assert((int)num_edges > 0, "need non-zero edge count for loop progress"); _outcnt -= num_edges; _del_tick += num_edges; // Make sure we are still in sync, possibly with no more out-edges: const Node* node = _node; verify(node, true); assert(node->_last_del == _last, "must have deleted the edge just produced"); } #endif //OPTO_DU_ITERATOR_ASSERT #endif //ASSERT // This constant used to initialize _out may be any non-null value. // The value NULL is reserved for the top node only. #define NO_OUT_ARRAY ((Node**)-1) // This funny expression handshakes with Node::operator new // to pull Compile::current out of the new node's _out field, // and then calls a subroutine which manages most field // initializations. The only one which is tricky is the // _idx field, which is const, and so must be initialized // by a return value, not an assignment. // // (Aren't you thankful that Java finals don't require so many tricks?) #define IDX_INIT(req) this->Init((req), (Compile*) this->_out) #ifdef _MSC_VER // the IDX_INIT hack falls foul of warning C4355 #pragma warning( disable:4355 ) // 'this' : used in base member initializer list #endif #ifdef __clang__ #pragma clang diagnostic push #pragma GCC diagnostic ignored "-Wuninitialized" #endif // Out-of-line code from node constructors. // Executed only when extra debug info. is being passed around. static void init_node_notes(Compile* C, int idx, Node_Notes* nn) { C->set_node_notes_at(idx, nn); } // Shared initialization code. inline int Node::Init(int req, Compile* C) { assert(Compile::current() == C, "must use operator new(Compile*)"); int idx = C->next_unique(); // Allocate memory for the necessary number of edges. if (req > 0) { // Allocate space for _in array to have double alignment. _in = (Node **) ((char *) (C->node_arena()->Amalloc_D(req * sizeof(void*)))); #ifdef ASSERT _in[req-1] = this; // magic cookie for assertion check #endif } // If there are default notes floating around, capture them: Node_Notes* nn = C->default_node_notes(); if (nn != NULL) init_node_notes(C, idx, nn); // Note: At this point, C is dead, // and we begin to initialize the new Node. _cnt = _max = req; _outcnt = _outmax = 0; _class_id = Class_Node; _flags = 0; _out = NO_OUT_ARRAY; return idx; } //------------------------------Node------------------------------------------- // Create a Node, with a given number of required edges. Node::Node(uint req) : _idx(IDX_INIT(req)) #ifdef ASSERT , _parse_idx(_idx) #endif { assert( req < Compile::current()->max_node_limit() - NodeLimitFudgeFactor, "Input limit exceeded" ); debug_only( verify_construction() ); NOT_PRODUCT(nodes_created++); if (req == 0) { assert( _in == (Node**)this, "Must not pass arg count to 'new'" ); _in = NULL; } else { assert( _in[req-1] == this, "Must pass arg count to 'new'" ); Node** to = _in; for(uint i = 0; i < req; i++) { to[i] = NULL; } } } //------------------------------Node------------------------------------------- Node::Node(Node *n0) : _idx(IDX_INIT(1)) #ifdef ASSERT , _parse_idx(_idx) #endif { debug_only( verify_construction() ); NOT_PRODUCT(nodes_created++); // Assert we allocated space for input array already assert( _in[0] == this, "Must pass arg count to 'new'" ); assert( is_not_dead(n0), "can not use dead node"); _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); } //------------------------------Node------------------------------------------- Node::Node(Node *n0, Node *n1) : _idx(IDX_INIT(2)) #ifdef ASSERT , _parse_idx(_idx) #endif { debug_only( verify_construction() ); NOT_PRODUCT(nodes_created++); // Assert we allocated space for input array already assert( _in[1] == this, "Must pass arg count to 'new'" ); assert( is_not_dead(n0), "can not use dead node"); assert( is_not_dead(n1), "can not use dead node"); _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this); } //------------------------------Node------------------------------------------- Node::Node(Node *n0, Node *n1, Node *n2) : _idx(IDX_INIT(3)) #ifdef ASSERT , _parse_idx(_idx) #endif { debug_only( verify_construction() ); NOT_PRODUCT(nodes_created++); // Assert we allocated space for input array already assert( _in[2] == this, "Must pass arg count to 'new'" ); assert( is_not_dead(n0), "can not use dead node"); assert( is_not_dead(n1), "can not use dead node"); assert( is_not_dead(n2), "can not use dead node"); _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this); _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this); } //------------------------------Node------------------------------------------- Node::Node(Node *n0, Node *n1, Node *n2, Node *n3) : _idx(IDX_INIT(4)) #ifdef ASSERT , _parse_idx(_idx) #endif { debug_only( verify_construction() ); NOT_PRODUCT(nodes_created++); // Assert we allocated space for input array already assert( _in[3] == this, "Must pass arg count to 'new'" ); assert( is_not_dead(n0), "can not use dead node"); assert( is_not_dead(n1), "can not use dead node"); assert( is_not_dead(n2), "can not use dead node"); assert( is_not_dead(n3), "can not use dead node"); _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this); _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this); _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this); } //------------------------------Node------------------------------------------- Node::Node(Node *n0, Node *n1, Node *n2, Node *n3, Node *n4) : _idx(IDX_INIT(5)) #ifdef ASSERT , _parse_idx(_idx) #endif { debug_only( verify_construction() ); NOT_PRODUCT(nodes_created++); // Assert we allocated space for input array already assert( _in[4] == this, "Must pass arg count to 'new'" ); assert( is_not_dead(n0), "can not use dead node"); assert( is_not_dead(n1), "can not use dead node"); assert( is_not_dead(n2), "can not use dead node"); assert( is_not_dead(n3), "can not use dead node"); assert( is_not_dead(n4), "can not use dead node"); _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this); _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this); _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this); _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this); } //------------------------------Node------------------------------------------- Node::Node(Node *n0, Node *n1, Node *n2, Node *n3, Node *n4, Node *n5) : _idx(IDX_INIT(6)) #ifdef ASSERT , _parse_idx(_idx) #endif { debug_only( verify_construction() ); NOT_PRODUCT(nodes_created++); // Assert we allocated space for input array already assert( _in[5] == this, "Must pass arg count to 'new'" ); assert( is_not_dead(n0), "can not use dead node"); assert( is_not_dead(n1), "can not use dead node"); assert( is_not_dead(n2), "can not use dead node"); assert( is_not_dead(n3), "can not use dead node"); assert( is_not_dead(n4), "can not use dead node"); assert( is_not_dead(n5), "can not use dead node"); _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this); _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this); _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this); _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this); _in[5] = n5; if (n5 != NULL) n5->add_out((Node *)this); } //------------------------------Node------------------------------------------- Node::Node(Node *n0, Node *n1, Node *n2, Node *n3, Node *n4, Node *n5, Node *n6) : _idx(IDX_INIT(7)) #ifdef ASSERT , _parse_idx(_idx) #endif { debug_only( verify_construction() ); NOT_PRODUCT(nodes_created++); // Assert we allocated space for input array already assert( _in[6] == this, "Must pass arg count to 'new'" ); assert( is_not_dead(n0), "can not use dead node"); assert( is_not_dead(n1), "can not use dead node"); assert( is_not_dead(n2), "can not use dead node"); assert( is_not_dead(n3), "can not use dead node"); assert( is_not_dead(n4), "can not use dead node"); assert( is_not_dead(n5), "can not use dead node"); assert( is_not_dead(n6), "can not use dead node"); _in[0] = n0; if (n0 != NULL) n0->add_out((Node *)this); _in[1] = n1; if (n1 != NULL) n1->add_out((Node *)this); _in[2] = n2; if (n2 != NULL) n2->add_out((Node *)this); _in[3] = n3; if (n3 != NULL) n3->add_out((Node *)this); _in[4] = n4; if (n4 != NULL) n4->add_out((Node *)this); _in[5] = n5; if (n5 != NULL) n5->add_out((Node *)this); _in[6] = n6; if (n6 != NULL) n6->add_out((Node *)this); } #ifdef __clang__ #pragma clang diagnostic pop #endif //------------------------------clone------------------------------------------ // Clone a Node. Node *Node::clone() const { Compile* C = Compile::current(); uint s = size_of(); // Size of inherited Node Node *n = (Node*)C->node_arena()->Amalloc_D(size_of() + _max*sizeof(Node*)); Copy::conjoint_words_to_lower((HeapWord*)this, (HeapWord*)n, s); // Set the new input pointer array n->_in = (Node**)(((char*)n)+s); // Cannot share the old output pointer array, so kill it n->_out = NO_OUT_ARRAY; // And reset the counters to 0 n->_outcnt = 0; n->_outmax = 0; // Unlock this guy, since he is not in any hash table. debug_only(n->_hash_lock = 0); // Walk the old node's input list to duplicate its edges uint i; for( i = 0; i < len(); i++ ) { Node *x = in(i); n->_in[i] = x; if (x != NULL) x->add_out(n); } if (is_macro()) C->add_macro_node(n); if (is_expensive()) C->add_expensive_node(n); // If the cloned node is a range check dependent CastII, add it to the list. CastIINode* cast = n->isa_CastII(); if (cast != NULL && cast->has_range_check()) { C->add_range_check_cast(cast); } n->set_idx(C->next_unique()); // Get new unique index as well debug_only( n->verify_construction() ); NOT_PRODUCT(nodes_created++); // Do not patch over the debug_idx of a clone, because it makes it // impossible to break on the clone's moment of creation. //debug_only( n->set_debug_idx( debug_idx() ) ); C->copy_node_notes_to(n, (Node*) this); // MachNode clone uint nopnds; if (this->is_Mach() && (nopnds = this->as_Mach()->num_opnds()) > 0) { MachNode *mach = n->as_Mach(); MachNode *mthis = this->as_Mach(); // Get address of _opnd_array. // It should be the same offset since it is the clone of this node. MachOper **from = mthis->_opnds; MachOper **to = (MachOper **)((size_t)(&mach->_opnds) + pointer_delta((const void*)from, (const void*)(&mthis->_opnds), 1)); mach->_opnds = to; for ( uint i = 0; i < nopnds; ++i ) { to[i] = from[i]->clone(C); } } // cloning CallNode may need to clone JVMState if (n->is_Call()) { n->as_Call()->clone_jvms(C); } if (n->is_SafePoint()) { n->as_SafePoint()->clone_replaced_nodes(); } return n; // Return the clone } //---------------------------setup_is_top-------------------------------------- // Call this when changing the top node, to reassert the invariants // required by Node::is_top. See Compile::set_cached_top_node. void Node::setup_is_top() { if (this == (Node*)Compile::current()->top()) { // This node has just become top. Kill its out array. _outcnt = _outmax = 0; _out = NULL; // marker value for top assert(is_top(), "must be top"); } else { if (_out == NULL) _out = NO_OUT_ARRAY; assert(!is_top(), "must not be top"); } } //------------------------------~Node------------------------------------------ // Fancy destructor; eagerly attempt to reclaim Node numberings and storage extern int reclaim_idx ; extern int reclaim_in ; extern int reclaim_node; void Node::destruct() { // Eagerly reclaim unique Node numberings Compile* compile = Compile::current(); if ((uint)_idx+1 == compile->unique()) { compile->set_unique(compile->unique()-1); #ifdef ASSERT reclaim_idx++; #endif } // Clear debug info: Node_Notes* nn = compile->node_notes_at(_idx); if (nn != NULL) nn->clear(); // Walk the input array, freeing the corresponding output edges _cnt = _max; // forget req/prec distinction uint i; for( i = 0; i < _max; i++ ) { set_req(i, NULL); //assert(def->out(def->outcnt()-1) == (Node *)this,"bad def-use hacking in reclaim"); } assert(outcnt() == 0, "deleting a node must not leave a dangling use"); // See if the input array was allocated just prior to the object int edge_size = _max*sizeof(void*); int out_edge_size = _outmax*sizeof(void*); char *edge_end = ((char*)_in) + edge_size; char *out_array = (char*)(_out == NO_OUT_ARRAY? NULL: _out); char *out_edge_end = out_array + out_edge_size; int node_size = size_of(); // Free the output edge array if (out_edge_size > 0) { #ifdef ASSERT if( out_edge_end == compile->node_arena()->hwm() ) reclaim_in += out_edge_size; // count reclaimed out edges with in edges #endif compile->node_arena()->Afree(out_array, out_edge_size); } // Free the input edge array and the node itself if( edge_end == (char*)this ) { #ifdef ASSERT if( edge_end+node_size == compile->node_arena()->hwm() ) { reclaim_in += edge_size; reclaim_node+= node_size; } #else // It was; free the input array and object all in one hit compile->node_arena()->Afree(_in,edge_size+node_size); #endif } else { // Free just the input array #ifdef ASSERT if( edge_end == compile->node_arena()->hwm() ) reclaim_in += edge_size; #endif compile->node_arena()->Afree(_in,edge_size); // Free just the object #ifdef ASSERT if( ((char*)this) + node_size == compile->node_arena()->hwm() ) reclaim_node+= node_size; #else compile->node_arena()->Afree(this,node_size); #endif } if (is_macro()) { compile->remove_macro_node(this); } if (is_expensive()) { compile->remove_expensive_node(this); } CastIINode* cast = isa_CastII(); if (cast != NULL && cast->has_range_check()) { compile->remove_range_check_cast(cast); } if (is_SafePoint()) { as_SafePoint()->delete_replaced_nodes(); } #ifdef ASSERT // We will not actually delete the storage, but we'll make the node unusable. *(address*)this = badAddress; // smash the C++ vtbl, probably _in = _out = (Node**) badAddress; _max = _cnt = _outmax = _outcnt = 0; #endif } //------------------------------grow------------------------------------------- // Grow the input array, making space for more edges void Node::grow( uint len ) { Arena* arena = Compile::current()->node_arena(); uint new_max = _max; if( new_max == 0 ) { _max = 4; _in = (Node**)arena->Amalloc(4*sizeof(Node*)); Node** to = _in; to[0] = NULL; to[1] = NULL; to[2] = NULL; to[3] = NULL; return; } while( new_max <= len ) new_max <<= 1; // Find next power-of-2 // Trimming to limit allows a uint8 to handle up to 255 edges. // Previously I was using only powers-of-2 which peaked at 128 edges. //if( new_max >= limit ) new_max = limit-1; _in = (Node**)arena->Arealloc(_in, _max*sizeof(Node*), new_max*sizeof(Node*)); Copy::zero_to_bytes(&_in[_max], (new_max-_max)*sizeof(Node*)); // NULL all new space _max = new_max; // Record new max length // This assertion makes sure that Node::_max is wide enough to // represent the numerical value of new_max. assert(_max == new_max && _max > len, "int width of _max is too small"); } //-----------------------------out_grow---------------------------------------- // Grow the input array, making space for more edges void Node::out_grow( uint len ) { assert(!is_top(), "cannot grow a top node's out array"); Arena* arena = Compile::current()->node_arena(); uint new_max = _outmax; if( new_max == 0 ) { _outmax = 4; _out = (Node **)arena->Amalloc(4*sizeof(Node*)); return; } while( new_max <= len ) new_max <<= 1; // Find next power-of-2 // Trimming to limit allows a uint8 to handle up to 255 edges. // Previously I was using only powers-of-2 which peaked at 128 edges. //if( new_max >= limit ) new_max = limit-1; assert(_out != NULL && _out != NO_OUT_ARRAY, "out must have sensible value"); _out = (Node**)arena->Arealloc(_out,_outmax*sizeof(Node*),new_max*sizeof(Node*)); //Copy::zero_to_bytes(&_out[_outmax], (new_max-_outmax)*sizeof(Node*)); // NULL all new space _outmax = new_max; // Record new max length // This assertion makes sure that Node::_max is wide enough to // represent the numerical value of new_max. assert(_outmax == new_max && _outmax > len, "int width of _outmax is too small"); } #ifdef ASSERT //------------------------------is_dead---------------------------------------- bool Node::is_dead() const { // Mach and pinch point nodes may look like dead. if( is_top() || is_Mach() || (Opcode() == Op_Node && _outcnt > 0) ) return false; for( uint i = 0; i < _max; i++ ) if( _in[i] != NULL ) return false; dump(); return true; } #endif //------------------------------is_unreachable--------------------------------- bool Node::is_unreachable(PhaseIterGVN &igvn) const { assert(!is_Mach(), "doesn't work with MachNodes"); return outcnt() == 0 || igvn.type(this) == Type::TOP || in(0)->is_top(); } //------------------------------add_req---------------------------------------- // Add a new required input at the end void Node::add_req( Node *n ) { assert( is_not_dead(n), "can not use dead node"); // Look to see if I can move precedence down one without reallocating if( (_cnt >= _max) || (in(_max-1) != NULL) ) grow( _max+1 ); // Find a precedence edge to move if( in(_cnt) != NULL ) { // Next precedence edge is busy? uint i; for( i=_cnt; i<_max; i++ ) if( in(i) == NULL ) // Find the NULL at end of prec edge list break; // There must be one, since we grew the array _in[i] = in(_cnt); // Move prec over, making space for req edge } _in[_cnt++] = n; // Stuff over old prec edge if (n != NULL) n->add_out((Node *)this); } //---------------------------add_req_batch------------------------------------- // Add a new required input at the end void Node::add_req_batch( Node *n, uint m ) { assert( is_not_dead(n), "can not use dead node"); // check various edge cases if ((int)m <= 1) { assert((int)m >= 0, "oob"); if (m != 0) add_req(n); return; } // Look to see if I can move precedence down one without reallocating if( (_cnt+m) > _max || _in[_max-m] ) grow( _max+m ); // Find a precedence edge to move if( _in[_cnt] != NULL ) { // Next precedence edge is busy? uint i; for( i=_cnt; i<_max; i++ ) if( _in[i] == NULL ) // Find the NULL at end of prec edge list break; // There must be one, since we grew the array // Slide all the precs over by m positions (assume #prec << m). Copy::conjoint_words_to_higher((HeapWord*)&_in[_cnt], (HeapWord*)&_in[_cnt+m], ((i-_cnt)*sizeof(Node*))); } // Stuff over the old prec edges for(uint i=0; iis_top()) { for(uint i=0; iadd_out((Node *)this); } } } //------------------------------del_req---------------------------------------- // Delete the required edge and compact the edge array void Node::del_req( uint idx ) { assert( idx < _cnt, "oob"); assert( !VerifyHashTableKeys || _hash_lock == 0, "remove node from hash table before modifying it"); // First remove corresponding def-use edge Node *n = in(idx); if (n != NULL) n->del_out((Node *)this); _in[idx] = in(--_cnt); // Compact the array _in[_cnt] = NULL; // NULL out emptied slot } //------------------------------del_req_ordered-------------------------------- // Delete the required edge and compact the edge array with preserved order void Node::del_req_ordered( uint idx ) { assert( idx < _cnt, "oob"); assert( !VerifyHashTableKeys || _hash_lock == 0, "remove node from hash table before modifying it"); // First remove corresponding def-use edge Node *n = in(idx); if (n != NULL) n->del_out((Node *)this); if (idx < _cnt - 1) { // Not last edge ? Copy::conjoint_words_to_lower((HeapWord*)&_in[idx+1], (HeapWord*)&_in[idx], ((_cnt-idx-1)*sizeof(Node*))); } _in[--_cnt] = NULL; // NULL out emptied slot } //------------------------------ins_req---------------------------------------- // Insert a new required input at the end void Node::ins_req( uint idx, Node *n ) { assert( is_not_dead(n), "can not use dead node"); add_req(NULL); // Make space assert( idx < _max, "Must have allocated enough space"); // Slide over if(_cnt-idx-1 > 0) { Copy::conjoint_words_to_higher((HeapWord*)&_in[idx], (HeapWord*)&_in[idx+1], ((_cnt-idx-1)*sizeof(Node*))); } _in[idx] = n; // Stuff over old required edge if (n != NULL) n->add_out((Node *)this); // Add reciprocal def-use edge } //-----------------------------find_edge--------------------------------------- int Node::find_edge(Node* n) { for (uint i = 0; i < len(); i++) { if (_in[i] == n) return i; } return -1; } //----------------------------replace_edge------------------------------------- int Node::replace_edge(Node* old, Node* neww) { if (old == neww) return 0; // nothing to do uint nrep = 0; for (uint i = 0; i < len(); i++) { if (in(i) == old) { if (i < req()) set_req(i, neww); else set_prec(i, neww); nrep++; } } return nrep; } /** * Replace input edges in the range pointing to 'old' node. */ int Node::replace_edges_in_range(Node* old, Node* neww, int start, int end) { if (old == neww) return 0; // nothing to do uint nrep = 0; for (int i = start; i < end; i++) { if (in(i) == old) { set_req(i, neww); nrep++; } } return nrep; } //-------------------------disconnect_inputs----------------------------------- // NULL out all inputs to eliminate incoming Def-Use edges. // Return the number of edges between 'n' and 'this' int Node::disconnect_inputs(Node *n, Compile* C) { int edges_to_n = 0; uint cnt = req(); for( uint i = 0; i < cnt; ++i ) { if( in(i) == 0 ) continue; if( in(i) == n ) ++edges_to_n; set_req(i, NULL); } // Remove precedence edges if any exist // Note: Safepoints may have precedence edges, even during parsing if( (req() != len()) && (in(req()) != NULL) ) { uint max = len(); for( uint i = 0; i < max; ++i ) { if( in(i) == 0 ) continue; if( in(i) == n ) ++edges_to_n; set_prec(i, NULL); } } // Node::destruct requires all out edges be deleted first // debug_only(destruct();) // no reuse benefit expected if (edges_to_n == 0) { C->record_dead_node(_idx); } return edges_to_n; } //-----------------------------uncast--------------------------------------- // %%% Temporary, until we sort out CheckCastPP vs. CastPP. // Strip away casting. (It is depth-limited.) Node* Node::uncast() const { // Should be inline: //return is_ConstraintCast() ? uncast_helper(this) : (Node*) this; if (is_ConstraintCast() || is_CheckCastPP()) return uncast_helper(this); else return (Node*) this; } //---------------------------uncast_helper------------------------------------- Node* Node::uncast_helper(const Node* p) { #ifdef ASSERT uint depth_count = 0; const Node* orig_p = p; #endif while (true) { #ifdef ASSERT if (depth_count >= K) { orig_p->dump(4); if (p != orig_p) p->dump(1); } assert(depth_count++ < K, "infinite loop in Node::uncast_helper"); #endif if (p == NULL || p->req() != 2) { break; } else if (p->is_ConstraintCast()) { p = p->in(1); } else if (p->is_CheckCastPP()) { p = p->in(1); } else { break; } } return (Node*) p; } //------------------------------add_prec--------------------------------------- // Add a new precedence input. Precedence inputs are unordered, with // duplicates removed and NULLs packed down at the end. void Node::add_prec( Node *n ) { assert( is_not_dead(n), "can not use dead node"); // Check for NULL at end if( _cnt >= _max || in(_max-1) ) grow( _max+1 ); // Find a precedence edge to move uint i = _cnt; while( in(i) != NULL ) i++; _in[i] = n; // Stuff prec edge over NULL if ( n != NULL) n->add_out((Node *)this); // Add mirror edge } //------------------------------rm_prec---------------------------------------- // Remove a precedence input. Precedence inputs are unordered, with // duplicates removed and NULLs packed down at the end. void Node::rm_prec( uint j ) { // Find end of precedence list to pack NULLs uint i; for( i=j; i<_max; i++ ) if( !_in[i] ) // Find the NULL at end of prec edge list break; if (_in[j] != NULL) _in[j]->del_out((Node *)this); _in[j] = _in[--i]; // Move last element over removed guy _in[i] = NULL; // NULL out last element } //------------------------------size_of---------------------------------------- uint Node::size_of() const { return sizeof(*this); } //------------------------------ideal_reg-------------------------------------- uint Node::ideal_reg() const { return 0; } //------------------------------jvms------------------------------------------- JVMState* Node::jvms() const { return NULL; } #ifdef ASSERT //------------------------------jvms------------------------------------------- bool Node::verify_jvms(const JVMState* using_jvms) const { for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) { if (jvms == using_jvms) return true; } return false; } //------------------------------init_NodeProperty------------------------------ void Node::init_NodeProperty() { assert(_max_classes <= max_jushort, "too many NodeProperty classes"); assert(_max_flags <= max_jushort, "too many NodeProperty flags"); } #endif //------------------------------format----------------------------------------- // Print as assembly void Node::format( PhaseRegAlloc *, outputStream *st ) const {} //------------------------------emit------------------------------------------- // Emit bytes starting at parameter 'ptr'. void Node::emit(CodeBuffer &cbuf, PhaseRegAlloc *ra_) const {} //------------------------------size------------------------------------------- // Size of instruction in bytes uint Node::size(PhaseRegAlloc *ra_) const { return 0; } //------------------------------CFG Construction------------------------------- // Nodes that end basic blocks, e.g. IfTrue/IfFalse, JumpProjNode, Root, // Goto and Return. const Node *Node::is_block_proj() const { return 0; } // Minimum guaranteed type const Type *Node::bottom_type() const { return Type::BOTTOM; } //------------------------------raise_bottom_type------------------------------ // Get the worst-case Type output for this Node. void Node::raise_bottom_type(const Type* new_type) { if (is_Type()) { TypeNode *n = this->as_Type(); if (VerifyAliases) { assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type"); } n->set_type(new_type); } else if (is_Load()) { LoadNode *n = this->as_Load(); if (VerifyAliases) { assert(new_type->higher_equal_speculative(n->type()), "new type must refine old type"); } n->set_type(new_type); } } //------------------------------Identity--------------------------------------- // Return a node that the given node is equivalent to. Node *Node::Identity( PhaseTransform * ) { return this; // Default to no identities } //------------------------------Value------------------------------------------ // Compute a new Type for a node using the Type of the inputs. const Type *Node::Value( PhaseTransform * ) const { return bottom_type(); // Default to worst-case Type } //------------------------------Ideal------------------------------------------ // // 'Idealize' the graph rooted at this Node. // // In order to be efficient and flexible there are some subtle invariants // these Ideal calls need to hold. Running with '+VerifyIterativeGVN' checks // these invariants, although its too slow to have on by default. If you are // hacking an Ideal call, be sure to test with +VerifyIterativeGVN! // // The Ideal call almost arbitrarily reshape the graph rooted at the 'this' // pointer. If ANY change is made, it must return the root of the reshaped // graph - even if the root is the same Node. Example: swapping the inputs // to an AddINode gives the same answer and same root, but you still have to // return the 'this' pointer instead of NULL. // // You cannot return an OLD Node, except for the 'this' pointer. Use the // Identity call to return an old Node; basically if Identity can find // another Node have the Ideal call make no change and return NULL. // Example: AddINode::Ideal must check for add of zero; in this case it // returns NULL instead of doing any graph reshaping. // // You cannot modify any old Nodes except for the 'this' pointer. Due to // sharing there may be other users of the old Nodes relying on their current // semantics. Modifying them will break the other users. // Example: when reshape "(X+3)+4" into "X+7" you must leave the Node for // "X+3" unchanged in case it is shared. // // If you modify the 'this' pointer's inputs, you should use // 'set_req'. If you are making a new Node (either as the new root or // some new internal piece) you may use 'init_req' to set the initial // value. You can make a new Node with either 'new' or 'clone'. In // either case, def-use info is correctly maintained. // // Example: reshape "(X+3)+4" into "X+7": // set_req(1, in(1)->in(1)); // set_req(2, phase->intcon(7)); // return this; // Example: reshape "X*4" into "X<<2" // return new (C) LShiftINode(in(1), phase->intcon(2)); // // You must call 'phase->transform(X)' on any new Nodes X you make, except // for the returned root node. Example: reshape "X*31" with "(X<<5)-X". // Node *shift=phase->transform(new(C)LShiftINode(in(1),phase->intcon(5))); // return new (C) AddINode(shift, in(1)); // // When making a Node for a constant use 'phase->makecon' or 'phase->intcon'. // These forms are faster than 'phase->transform(new (C) ConNode())' and Do // The Right Thing with def-use info. // // You cannot bury the 'this' Node inside of a graph reshape. If the reshaped // graph uses the 'this' Node it must be the root. If you want a Node with // the same Opcode as the 'this' pointer use 'clone'. // Node *Node::Ideal(PhaseGVN *phase, bool can_reshape) { return NULL; // Default to being Ideal already } // Some nodes have specific Ideal subgraph transformations only if they are // unique users of specific nodes. Such nodes should be put on IGVN worklist // for the transformations to happen. bool Node::has_special_unique_user() const { assert(outcnt() == 1, "match only for unique out"); Node* n = unique_out(); int op = Opcode(); if( this->is_Store() ) { // Condition for back-to-back stores folding. return n->Opcode() == op && n->in(MemNode::Memory) == this; } else if (this->is_Load()) { // Condition for removing an unused LoadNode from the MemBarAcquire precedence input return n->Opcode() == Op_MemBarAcquire; } else if( op == Op_AddL ) { // Condition for convL2I(addL(x,y)) ==> addI(convL2I(x),convL2I(y)) return n->Opcode() == Op_ConvL2I && n->in(1) == this; } else if( op == Op_SubI || op == Op_SubL ) { // Condition for subI(x,subI(y,z)) ==> subI(addI(x,z),y) return n->Opcode() == op && n->in(2) == this; } return false; }; //--------------------------find_exact_control--------------------------------- // Skip Proj and CatchProj nodes chains. Check for Null and Top. Node* Node::find_exact_control(Node* ctrl) { if (ctrl == NULL && this->is_Region()) ctrl = this->as_Region()->is_copy(); if (ctrl != NULL && ctrl->is_CatchProj()) { if (ctrl->as_CatchProj()->_con == CatchProjNode::fall_through_index) ctrl = ctrl->in(0); if (ctrl != NULL && !ctrl->is_top()) ctrl = ctrl->in(0); } if (ctrl != NULL && ctrl->is_Proj()) ctrl = ctrl->in(0); return ctrl; } //--------------------------dominates------------------------------------------ // Helper function for MemNode::all_controls_dominate(). // Check if 'this' control node dominates or equal to 'sub' control node. // We already know that if any path back to Root or Start reaches 'this', // then all paths so, so this is a simple search for one example, // not an exhaustive search for a counterexample. bool Node::dominates(Node* sub, Node_List &nlist) { assert(this->is_CFG(), "expecting control"); assert(sub != NULL && sub->is_CFG(), "expecting control"); // detect dead cycle without regions int iterations_without_region_limit = DominatorSearchLimit; Node* orig_sub = sub; Node* dom = this; bool met_dom = false; nlist.clear(); // Walk 'sub' backward up the chain to 'dom', watching for regions. // After seeing 'dom', continue up to Root or Start. // If we hit a region (backward split point), it may be a loop head. // Keep going through one of the region's inputs. If we reach the // same region again, go through a different input. Eventually we // will either exit through the loop head, or give up. // (If we get confused, break out and return a conservative 'false'.) while (sub != NULL) { if (sub->is_top()) break; // Conservative answer for dead code. if (sub == dom) { if (nlist.size() == 0) { // No Region nodes except loops were visited before and the EntryControl // path was taken for loops: it did not walk in a cycle. return true; } else if (met_dom) { break; // already met before: walk in a cycle } else { // Region nodes were visited. Continue walk up to Start or Root // to make sure that it did not walk in a cycle. met_dom = true; // first time meet iterations_without_region_limit = DominatorSearchLimit; // Reset } } if (sub->is_Start() || sub->is_Root()) { // Success if we met 'dom' along a path to Start or Root. // We assume there are no alternative paths that avoid 'dom'. // (This assumption is up to the caller to ensure!) return met_dom; } Node* up = sub->in(0); // Normalize simple pass-through regions and projections: up = sub->find_exact_control(up); // If sub == up, we found a self-loop. Try to push past it. if (sub == up && sub->is_Loop()) { // Take loop entry path on the way up to 'dom'. up = sub->in(1); // in(LoopNode::EntryControl); } else if (sub == up && sub->is_Region() && sub->req() != 3) { // Always take in(1) path on the way up to 'dom' for clone regions // (with only one input) or regions which merge > 2 paths // (usually used to merge fast/slow paths). up = sub->in(1); } else if (sub == up && sub->is_Region()) { // Try both paths for Regions with 2 input paths (it may be a loop head). // It could give conservative 'false' answer without information // which region's input is the entry path. iterations_without_region_limit = DominatorSearchLimit; // Reset bool region_was_visited_before = false; // Was this Region node visited before? // If so, we have reached it because we accidentally took a // loop-back edge from 'sub' back into the body of the loop, // and worked our way up again to the loop header 'sub'. // So, take the first unexplored path on the way up to 'dom'. for (int j = nlist.size() - 1; j >= 0; j--) { intptr_t ni = (intptr_t)nlist.at(j); Node* visited = (Node*)(ni & ~1); bool visited_twice_already = ((ni & 1) != 0); if (visited == sub) { if (visited_twice_already) { // Visited 2 paths, but still stuck in loop body. Give up. return false; } // The Region node was visited before only once. // (We will repush with the low bit set, below.) nlist.remove(j); // We will find a new edge and re-insert. region_was_visited_before = true; break; } } // Find an incoming edge which has not been seen yet; walk through it. assert(up == sub, ""); uint skip = region_was_visited_before ? 1 : 0; for (uint i = 1; i < sub->req(); i++) { Node* in = sub->in(i); if (in != NULL && !in->is_top() && in != sub) { if (skip == 0) { up = in; break; } --skip; // skip this nontrivial input } } // Set 0 bit to indicate that both paths were taken. nlist.push((Node*)((intptr_t)sub + (region_was_visited_before ? 1 : 0))); } if (up == sub) { break; // some kind of tight cycle } if (up == orig_sub && met_dom) { // returned back after visiting 'dom' break; // some kind of cycle } if (--iterations_without_region_limit < 0) { break; // dead cycle } sub = up; } // Did not meet Root or Start node in pred. chain. // Conservative answer for dead code. return false; } //------------------------------remove_dead_region----------------------------- // This control node is dead. Follow the subgraph below it making everything // using it dead as well. This will happen normally via the usual IterGVN // worklist but this call is more efficient. Do not update use-def info // inside the dead region, just at the borders. static void kill_dead_code( Node *dead, PhaseIterGVN *igvn ) { // Con's are a popular node to re-hit in the hash table again. if( dead->is_Con() ) return; // Can't put ResourceMark here since igvn->_worklist uses the same arena // for verify pass with +VerifyOpto and we add/remove elements in it here. Node_List nstack(Thread::current()->resource_area()); Node *top = igvn->C->top(); nstack.push(dead); bool has_irreducible_loop = igvn->C->has_irreducible_loop(); while (nstack.size() > 0) { dead = nstack.pop(); if (dead->outcnt() > 0) { // Keep dead node on stack until all uses are processed. nstack.push(dead); // For all Users of the Dead... ;-) for (DUIterator_Last kmin, k = dead->last_outs(kmin); k >= kmin; ) { Node* use = dead->last_out(k); igvn->hash_delete(use); // Yank from hash table prior to mod if (use->in(0) == dead) { // Found another dead node assert (!use->is_Con(), "Control for Con node should be Root node."); use->set_req(0, top); // Cut dead edge to prevent processing nstack.push(use); // the dead node again. } else if (!has_irreducible_loop && // Backedge could be alive in irreducible loop use->is_Loop() && !use->is_Root() && // Don't kill Root (RootNode extends LoopNode) use->in(LoopNode::EntryControl) == dead) { // Dead loop if its entry is dead use->set_req(LoopNode::EntryControl, top); // Cut dead edge to prevent processing use->set_req(0, top); // Cut self edge nstack.push(use); } else { // Else found a not-dead user // Dead if all inputs are top or null bool dead_use = !use->is_Root(); // Keep empty graph alive for (uint j = 1; j < use->req(); j++) { Node* in = use->in(j); if (in == dead) { // Turn all dead inputs into TOP use->set_req(j, top); } else if (in != NULL && !in->is_top()) { dead_use = false; } } if (dead_use) { if (use->is_Region()) { use->set_req(0, top); // Cut self edge } nstack.push(use); } else { igvn->_worklist.push(use); } } // Refresh the iterator, since any number of kills might have happened. k = dead->last_outs(kmin); } } else { // (dead->outcnt() == 0) // Done with outputs. igvn->hash_delete(dead); igvn->_worklist.remove(dead); igvn->set_type(dead, Type::TOP); if (dead->is_macro()) { igvn->C->remove_macro_node(dead); } if (dead->is_expensive()) { igvn->C->remove_expensive_node(dead); } CastIINode* cast = dead->isa_CastII(); if (cast != NULL && cast->has_range_check()) { igvn->C->remove_range_check_cast(cast); } igvn->C->record_dead_node(dead->_idx); // Kill all inputs to the dead guy for (uint i=0; i < dead->req(); i++) { Node *n = dead->in(i); // Get input to dead guy if (n != NULL && !n->is_top()) { // Input is valid? dead->set_req(i, top); // Smash input away if (n->outcnt() == 0) { // Input also goes dead? if (!n->is_Con()) nstack.push(n); // Clear it out as well } else if (n->outcnt() == 1 && n->has_special_unique_user()) { igvn->add_users_to_worklist( n ); } else if (n->outcnt() <= 2 && n->is_Store()) { // Push store's uses on worklist to enable folding optimization for // store/store and store/load to the same address. // The restriction (outcnt() <= 2) is the same as in set_req_X() // and remove_globally_dead_node(). igvn->add_users_to_worklist( n ); } } } } // (dead->outcnt() == 0) } // while (nstack.size() > 0) for outputs return; } //------------------------------remove_dead_region----------------------------- bool Node::remove_dead_region(PhaseGVN *phase, bool can_reshape) { Node *n = in(0); if( !n ) return false; // Lost control into this guy? I.e., it became unreachable? // Aggressively kill all unreachable code. if (can_reshape && n->is_top()) { kill_dead_code(this, phase->is_IterGVN()); return false; // Node is dead. } if( n->is_Region() && n->as_Region()->is_copy() ) { Node *m = n->nonnull_req(); set_req(0, m); return true; } return false; } //------------------------------Ideal_DU_postCCP------------------------------- // Idealize graph, using DU info. Must clone result into new-space Node *Node::Ideal_DU_postCCP( PhaseCCP * ) { return NULL; // Default to no change } //------------------------------hash------------------------------------------- // Hash function over Nodes. uint Node::hash() const { uint sum = 0; for( uint i=0; i<_cnt; i++ ) // Add in all inputs sum = (sum<<1)-(uintptr_t)in(i); // Ignore embedded NULLs return (sum>>2) + _cnt + Opcode(); } //------------------------------cmp-------------------------------------------- // Compare special parts of simple Nodes uint Node::cmp( const Node &n ) const { return 1; // Must be same } //------------------------------rematerialize----------------------------------- // Should we clone rather than spill this instruction? bool Node::rematerialize() const { if ( is_Mach() ) return this->as_Mach()->rematerialize(); else return (_flags & Flag_rematerialize) != 0; } //------------------------------needs_anti_dependence_check--------------------- // Nodes which use memory without consuming it, hence need antidependences. bool Node::needs_anti_dependence_check() const { if( req() < 2 || (_flags & Flag_needs_anti_dependence_check) == 0 ) return false; else return in(1)->bottom_type()->has_memory(); } // Get an integer constant from a ConNode (or CastIINode). // Return a default value if there is no apparent constant here. const TypeInt* Node::find_int_type() const { if (this->is_Type()) { return this->as_Type()->type()->isa_int(); } else if (this->is_Con()) { assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode"); return this->bottom_type()->isa_int(); } return NULL; } // Get a pointer constant from a ConstNode. // Returns the constant if it is a pointer ConstNode intptr_t Node::get_ptr() const { assert( Opcode() == Op_ConP, "" ); return ((ConPNode*)this)->type()->is_ptr()->get_con(); } // Get a narrow oop constant from a ConNNode. intptr_t Node::get_narrowcon() const { assert( Opcode() == Op_ConN, "" ); return ((ConNNode*)this)->type()->is_narrowoop()->get_con(); } // Get a long constant from a ConNode. // Return a default value if there is no apparent constant here. const TypeLong* Node::find_long_type() const { if (this->is_Type()) { return this->as_Type()->type()->isa_long(); } else if (this->is_Con()) { assert(is_Mach(), "should be ConNode(TypeNode) or else a MachNode"); return this->bottom_type()->isa_long(); } return NULL; } /** * Return a ptr type for nodes which should have it. */ const TypePtr* Node::get_ptr_type() const { const TypePtr* tp = this->bottom_type()->make_ptr(); #ifdef ASSERT if (tp == NULL) { this->dump(1); assert((tp != NULL), "unexpected node type"); } #endif return tp; } // Get a double constant from a ConstNode. // Returns the constant if it is a double ConstNode jdouble Node::getd() const { assert( Opcode() == Op_ConD, "" ); return ((ConDNode*)this)->type()->is_double_constant()->getd(); } // Get a float constant from a ConstNode. // Returns the constant if it is a float ConstNode jfloat Node::getf() const { assert( Opcode() == Op_ConF, "" ); return ((ConFNode*)this)->type()->is_float_constant()->getf(); } #ifndef PRODUCT //----------------------------NotANode---------------------------------------- // Used in debugging code to avoid walking across dead or uninitialized edges. static inline bool NotANode(const Node* n) { if (n == NULL) return true; if (((intptr_t)n & 1) != 0) return true; // uninitialized, etc. if (*(address*)n == badAddress) return true; // kill by Node::destruct return false; } //------------------------------find------------------------------------------ // Find a neighbor of this Node with the given _idx // If idx is negative, find its absolute value, following both _in and _out. static void find_recur(Compile* C, Node* &result, Node *n, int idx, bool only_ctrl, VectorSet* old_space, VectorSet* new_space ) { int node_idx = (idx >= 0) ? idx : -idx; if (NotANode(n)) return; // Gracefully handle NULL, -1, 0xabababab, etc. // Contained in new_space or old_space? Check old_arena first since it's mostly empty. VectorSet *v = C->old_arena()->contains(n) ? old_space : new_space; if( v->test(n->_idx) ) return; if( (int)n->_idx == node_idx debug_only(|| n->debug_idx() == node_idx) ) { if (result != NULL) tty->print("find: " INTPTR_FORMAT " and " INTPTR_FORMAT " both have idx==%d\n", (uintptr_t)result, (uintptr_t)n, node_idx); result = n; } v->set(n->_idx); for( uint i=0; ilen(); i++ ) { if( only_ctrl && !(n->is_Region()) && (n->Opcode() != Op_Root) && (i != TypeFunc::Control) ) continue; find_recur(C, result, n->in(i), idx, only_ctrl, old_space, new_space ); } // Search along forward edges also: if (idx < 0 && !only_ctrl) { for( uint j=0; joutcnt(); j++ ) { find_recur(C, result, n->raw_out(j), idx, only_ctrl, old_space, new_space ); } } #ifdef ASSERT // Search along debug_orig edges last, checking for cycles Node* orig = n->debug_orig(); if (orig != NULL) { do { if (NotANode(orig)) break; find_recur(C, result, orig, idx, only_ctrl, old_space, new_space ); orig = orig->debug_orig(); } while (orig != NULL && orig != n->debug_orig()); } #endif //ASSERT } // call this from debugger: Node* find_node(Node* n, int idx) { return n->find(idx); } //------------------------------find------------------------------------------- Node* Node::find(int idx) const { ResourceArea *area = Thread::current()->resource_area(); VectorSet old_space(area), new_space(area); Node* result = NULL; find_recur(Compile::current(), result, (Node*) this, idx, false, &old_space, &new_space ); return result; } //------------------------------find_ctrl-------------------------------------- // Find an ancestor to this node in the control history with given _idx Node* Node::find_ctrl(int idx) const { ResourceArea *area = Thread::current()->resource_area(); VectorSet old_space(area), new_space(area); Node* result = NULL; find_recur(Compile::current(), result, (Node*) this, idx, true, &old_space, &new_space ); return result; } #endif #ifndef PRODUCT // -----------------------------Name------------------------------------------- extern const char *NodeClassNames[]; const char *Node::Name() const { return NodeClassNames[Opcode()]; } static bool is_disconnected(const Node* n) { for (uint i = 0; i < n->req(); i++) { if (n->in(i) != NULL) return false; } return true; } #ifdef ASSERT static void dump_orig(Node* orig, outputStream *st) { Compile* C = Compile::current(); if (NotANode(orig)) orig = NULL; if (orig != NULL && !C->node_arena()->contains(orig)) orig = NULL; if (orig == NULL) return; st->print(" !orig="); Node* fast = orig->debug_orig(); // tortoise & hare algorithm to detect loops if (NotANode(fast)) fast = NULL; while (orig != NULL) { bool discon = is_disconnected(orig); // if discon, print [123] else 123 if (discon) st->print("["); if (!Compile::current()->node_arena()->contains(orig)) st->print("o"); st->print("%d", orig->_idx); if (discon) st->print("]"); orig = orig->debug_orig(); if (NotANode(orig)) orig = NULL; if (orig != NULL && !C->node_arena()->contains(orig)) orig = NULL; if (orig != NULL) st->print(","); if (fast != NULL) { // Step fast twice for each single step of orig: fast = fast->debug_orig(); if (NotANode(fast)) fast = NULL; if (fast != NULL && fast != orig) { fast = fast->debug_orig(); if (NotANode(fast)) fast = NULL; } if (fast == orig) { st->print("..."); break; } } } } void Node::set_debug_orig(Node* orig) { _debug_orig = orig; if (BreakAtNode == 0) return; if (NotANode(orig)) orig = NULL; int trip = 10; while (orig != NULL) { if (orig->debug_idx() == BreakAtNode || (int)orig->_idx == BreakAtNode) { tty->print_cr("BreakAtNode: _idx=%d _debug_idx=%d orig._idx=%d orig._debug_idx=%d", this->_idx, this->debug_idx(), orig->_idx, orig->debug_idx()); BREAKPOINT; } orig = orig->debug_orig(); if (NotANode(orig)) orig = NULL; if (trip-- <= 0) break; } } #endif //ASSERT //------------------------------dump------------------------------------------ // Dump a Node void Node::dump(const char* suffix, outputStream *st) const { Compile* C = Compile::current(); bool is_new = C->node_arena()->contains(this); C->_in_dump_cnt++; st->print("%c%d\t%s\t=== ", is_new ? ' ' : 'o', _idx, Name()); // Dump the required and precedence inputs dump_req(st); dump_prec(st); // Dump the outputs dump_out(st); if (is_disconnected(this)) { #ifdef ASSERT st->print(" [%d]",debug_idx()); dump_orig(debug_orig(), st); #endif st->cr(); C->_in_dump_cnt--; return; // don't process dead nodes } // Dump node-specific info dump_spec(st); #ifdef ASSERT // Dump the non-reset _debug_idx if (Verbose && WizardMode) { st->print(" [%d]",debug_idx()); } #endif const Type *t = bottom_type(); if (t != NULL && (t->isa_instptr() || t->isa_klassptr())) { const TypeInstPtr *toop = t->isa_instptr(); const TypeKlassPtr *tkls = t->isa_klassptr(); ciKlass* klass = toop ? toop->klass() : (tkls ? tkls->klass() : NULL ); if (klass && klass->is_loaded() && klass->is_interface()) { st->print(" Interface:"); } else if (toop) { st->print(" Oop:"); } else if (tkls) { st->print(" Klass:"); } t->dump_on(st); } else if (t == Type::MEMORY) { st->print(" Memory:"); MemNode::dump_adr_type(this, adr_type(), st); } else if (Verbose || WizardMode) { st->print(" Type:"); if (t) { t->dump_on(st); } else { st->print("no type"); } } else if (t->isa_vect() && this->is_MachSpillCopy()) { // Dump MachSpillcopy vector type. t->dump_on(st); } if (is_new) { debug_only(dump_orig(debug_orig(), st)); Node_Notes* nn = C->node_notes_at(_idx); if (nn != NULL && !nn->is_clear()) { if (nn->jvms() != NULL) { st->print(" !jvms:"); nn->jvms()->dump_spec(st); } } } if (suffix) st->print("%s", suffix); C->_in_dump_cnt--; } //------------------------------dump_req-------------------------------------- void Node::dump_req(outputStream *st) const { // Dump the required input edges for (uint i = 0; i < req(); i++) { // For all required inputs Node* d = in(i); if (d == NULL) { st->print("_ "); } else if (NotANode(d)) { st->print("NotANode "); // uninitialized, sentinel, garbage, etc. } else { st->print("%c%d ", Compile::current()->node_arena()->contains(d) ? ' ' : 'o', d->_idx); } } } //------------------------------dump_prec------------------------------------- void Node::dump_prec(outputStream *st) const { // Dump the precedence edges int any_prec = 0; for (uint i = req(); i < len(); i++) { // For all precedence inputs Node* p = in(i); if (p != NULL) { if (!any_prec++) st->print(" |"); if (NotANode(p)) { st->print("NotANode "); continue; } st->print("%c%d ", Compile::current()->node_arena()->contains(in(i)) ? ' ' : 'o', in(i)->_idx); } } } //------------------------------dump_out-------------------------------------- void Node::dump_out(outputStream *st) const { // Delimit the output edges st->print(" [["); // Dump the output edges for (uint i = 0; i < _outcnt; i++) { // For all outputs Node* u = _out[i]; if (u == NULL) { st->print("_ "); } else if (NotANode(u)) { st->print("NotANode "); } else { st->print("%c%d ", Compile::current()->node_arena()->contains(u) ? ' ' : 'o', u->_idx); } } st->print("]] "); } //------------------------------dump_nodes------------------------------------- static void dump_nodes(const Node* start, int d, bool only_ctrl) { Node* s = (Node*)start; // remove const if (NotANode(s)) return; uint depth = (uint)ABS(d); int direction = d; Compile* C = Compile::current(); GrowableArray nstack(C->live_nodes()); nstack.append(s); int begin = 0; int end = 0; for(uint i = 0; i < depth; i++) { end = nstack.length(); for(int j = begin; j < end; j++) { Node* tp = nstack.at(j); uint limit = direction > 0 ? tp->len() : tp->outcnt(); for(uint k = 0; k < limit; k++) { Node* n = direction > 0 ? tp->in(k) : tp->raw_out(k); if (NotANode(n)) continue; // do not recurse through top or the root (would reach unrelated stuff) if (n->is_Root() || n->is_top()) continue; if (only_ctrl && !n->is_CFG()) continue; bool on_stack = nstack.contains(n); if (!on_stack) { nstack.append(n); } } } begin = end; } end = nstack.length(); if (direction > 0) { for(int j = end-1; j >= 0; j--) { nstack.at(j)->dump(); } } else { for(int j = 0; j < end; j++) { nstack.at(j)->dump(); } } } //------------------------------dump------------------------------------------- void Node::dump(int d) const { dump_nodes(this, d, false); } //------------------------------dump_ctrl-------------------------------------- // Dump a Node's control history to depth void Node::dump_ctrl(int d) const { dump_nodes(this, d, true); } // VERIFICATION CODE // For each input edge to a node (ie - for each Use-Def edge), verify that // there is a corresponding Def-Use edge. //------------------------------verify_edges----------------------------------- void Node::verify_edges(Unique_Node_List &visited) { uint i, j, idx; int cnt; Node *n; // Recursive termination test if (visited.member(this)) return; visited.push(this); // Walk over all input edges, checking for correspondence for( i = 0; i < len(); i++ ) { n = in(i); if (n != NULL && !n->is_top()) { // Count instances of (Node *)this cnt = 0; for (idx = 0; idx < n->_outcnt; idx++ ) { if (n->_out[idx] == (Node *)this) cnt++; } assert( cnt > 0,"Failed to find Def-Use edge." ); // Check for duplicate edges // walk the input array downcounting the input edges to n for( j = 0; j < len(); j++ ) { if( in(j) == n ) cnt--; } assert( cnt == 0,"Mismatched edge count."); } else if (n == NULL) { assert(i >= req() || i == 0 || is_Region() || is_Phi(), "only regions or phis have null data edges"); } else { assert(n->is_top(), "sanity"); // Nothing to check. } } // Recursive walk over all input edges for( i = 0; i < len(); i++ ) { n = in(i); if( n != NULL ) in(i)->verify_edges(visited); } } //------------------------------verify_recur----------------------------------- static const Node *unique_top = NULL; void Node::verify_recur(const Node *n, int verify_depth, VectorSet &old_space, VectorSet &new_space) { if ( verify_depth == 0 ) return; if (verify_depth > 0) --verify_depth; Compile* C = Compile::current(); // Contained in new_space or old_space? VectorSet *v = C->node_arena()->contains(n) ? &new_space : &old_space; // Check for visited in the proper space. Numberings are not unique // across spaces so we need a separate VectorSet for each space. if( v->test_set(n->_idx) ) return; if (n->is_Con() && n->bottom_type() == Type::TOP) { if (C->cached_top_node() == NULL) C->set_cached_top_node((Node*)n); assert(C->cached_top_node() == n, "TOP node must be unique"); } for( uint i = 0; i < n->len(); i++ ) { Node *x = n->in(i); if (!x || x->is_top()) continue; // Verify my input has a def-use edge to me if (true /*VerifyDefUse*/) { // Count use-def edges from n to x int cnt = 0; for( uint j = 0; j < n->len(); j++ ) if( n->in(j) == x ) cnt++; // Count def-use edges from x to n uint max = x->_outcnt; for( uint k = 0; k < max; k++ ) if (x->_out[k] == n) cnt--; assert( cnt == 0, "mismatched def-use edge counts" ); } verify_recur(x, verify_depth, old_space, new_space); } } //------------------------------verify----------------------------------------- // Check Def-Use info for my subgraph void Node::verify() const { Compile* C = Compile::current(); Node* old_top = C->cached_top_node(); ResourceMark rm; ResourceArea *area = Thread::current()->resource_area(); VectorSet old_space(area), new_space(area); verify_recur(this, -1, old_space, new_space); C->set_cached_top_node(old_top); } #endif //------------------------------walk------------------------------------------- // Graph walk, with both pre-order and post-order functions void Node::walk(NFunc pre, NFunc post, void *env) { VectorSet visited(Thread::current()->resource_area()); // Setup for local walk walk_(pre, post, env, visited); } void Node::walk_(NFunc pre, NFunc post, void *env, VectorSet &visited) { if( visited.test_set(_idx) ) return; pre(*this,env); // Call the pre-order walk function for( uint i=0; i<_max; i++ ) if( in(i) ) // Input exists and is not walked? in(i)->walk_(pre,post,env,visited); // Walk it with pre & post functions post(*this,env); // Call the post-order walk function } void Node::nop(Node &, void*) {} //------------------------------Registers-------------------------------------- // Do we Match on this edge index or not? Generally false for Control // and true for everything else. Weird for calls & returns. uint Node::match_edge(uint idx) const { return idx; // True for other than index 0 (control) } static RegMask _not_used_at_all; // Register classes are defined for specific machines const RegMask &Node::out_RegMask() const { ShouldNotCallThis(); return _not_used_at_all; } const RegMask &Node::in_RegMask(uint) const { ShouldNotCallThis(); return _not_used_at_all; } //============================================================================= //----------------------------------------------------------------------------- void Node_Array::reset( Arena *new_arena ) { _a->Afree(_nodes,_max*sizeof(Node*)); _max = 0; _nodes = NULL; _a = new_arena; } //------------------------------clear------------------------------------------ // Clear all entries in _nodes to NULL but keep storage void Node_Array::clear() { Copy::zero_to_bytes( _nodes, _max*sizeof(Node*) ); } //----------------------------------------------------------------------------- void Node_Array::grow( uint i ) { if( !_max ) { _max = 1; _nodes = (Node**)_a->Amalloc( _max * sizeof(Node*) ); _nodes[0] = NULL; } uint old = _max; while( i >= _max ) _max <<= 1; // Double to fit _nodes = (Node**)_a->Arealloc( _nodes, old*sizeof(Node*),_max*sizeof(Node*)); Copy::zero_to_bytes( &_nodes[old], (_max-old)*sizeof(Node*) ); } //----------------------------------------------------------------------------- void Node_Array::insert( uint i, Node *n ) { if( _nodes[_max-1] ) grow(_max); // Get more space if full Copy::conjoint_words_to_higher((HeapWord*)&_nodes[i], (HeapWord*)&_nodes[i+1], ((_max-i-1)*sizeof(Node*))); _nodes[i] = n; } //----------------------------------------------------------------------------- void Node_Array::remove( uint i ) { Copy::conjoint_words_to_lower((HeapWord*)&_nodes[i+1], (HeapWord*)&_nodes[i], ((_max-i-1)*sizeof(Node*))); _nodes[_max-1] = NULL; } //----------------------------------------------------------------------------- void Node_Array::sort( C_sort_func_t func) { qsort( _nodes, _max, sizeof( Node* ), func ); } //----------------------------------------------------------------------------- void Node_Array::dump() const { #ifndef PRODUCT for( uint i = 0; i < _max; i++ ) { Node *nn = _nodes[i]; if( nn != NULL ) { tty->print("%5d--> ",i); nn->dump(); } } #endif } //--------------------------is_iteratively_computed------------------------------ // Operation appears to be iteratively computed (such as an induction variable) // It is possible for this operation to return false for a loop-varying // value, if it appears (by local graph inspection) to be computed by a simple conditional. bool Node::is_iteratively_computed() { if (ideal_reg()) { // does operation have a result register? for (uint i = 1; i < req(); i++) { Node* n = in(i); if (n != NULL && n->is_Phi()) { for (uint j = 1; j < n->req(); j++) { if (n->in(j) == this) { return true; } } } } } return false; } //--------------------------find_similar------------------------------ // Return a node with opcode "opc" and same inputs as "this" if one can // be found; Otherwise return NULL; Node* Node::find_similar(int opc) { if (req() >= 2) { Node* def = in(1); if (def && def->outcnt() >= 2) { for (DUIterator_Fast dmax, i = def->fast_outs(dmax); i < dmax; i++) { Node* use = def->fast_out(i); if (use->Opcode() == opc && use->req() == req()) { uint j; for (j = 0; j < use->req(); j++) { if (use->in(j) != in(j)) { break; } } if (j == use->req()) { return use; } } } } } return NULL; } //--------------------------unique_ctrl_out------------------------------ // Return the unique control out if only one. Null if none or more than one. Node* Node::unique_ctrl_out() { Node* found = NULL; for (uint i = 0; i < outcnt(); i++) { Node* use = raw_out(i); if (use->is_CFG() && use != this) { if (found != NULL) return NULL; found = use; } } return found; } //============================================================================= //------------------------------yank------------------------------------------- // Find and remove void Node_List::yank( Node *n ) { uint i; for( i = 0; i < _cnt; i++ ) if( _nodes[i] == n ) break; if( i < _cnt ) _nodes[i] = _nodes[--_cnt]; } //------------------------------dump------------------------------------------- void Node_List::dump() const { #ifndef PRODUCT for( uint i = 0; i < _cnt; i++ ) if( _nodes[i] ) { tty->print("%5d--> ",i); _nodes[i]->dump(); } #endif } void Node_List::dump_simple() const { #ifndef PRODUCT for( uint i = 0; i < _cnt; i++ ) if( _nodes[i] ) { tty->print(" %d", _nodes[i]->_idx); } else { tty->print(" NULL"); } #endif } //============================================================================= //------------------------------remove----------------------------------------- void Unique_Node_List::remove( Node *n ) { if( _in_worklist[n->_idx] ) { for( uint i = 0; i < size(); i++ ) if( _nodes[i] == n ) { map(i,Node_List::pop()); _in_worklist >>= n->_idx; return; } ShouldNotReachHere(); } } //-----------------------remove_useless_nodes---------------------------------- // Remove useless nodes from worklist void Unique_Node_List::remove_useless_nodes(VectorSet &useful) { for( uint i = 0; i < size(); ++i ) { Node *n = at(i); assert( n != NULL, "Did not expect null entries in worklist"); if( ! useful.test(n->_idx) ) { _in_worklist >>= n->_idx; map(i,Node_List::pop()); // Node *replacement = Node_List::pop(); // if( i != size() ) { // Check if removing last entry // _nodes[i] = replacement; // } --i; // Visit popped node // If it was last entry, loop terminates since size() was also reduced } } } //============================================================================= void Node_Stack::grow() { size_t old_top = pointer_delta(_inode_top,_inodes,sizeof(INode)); // save _top size_t old_max = pointer_delta(_inode_max,_inodes,sizeof(INode)); size_t max = old_max << 1; // max * 2 _inodes = REALLOC_ARENA_ARRAY(_a, INode, _inodes, old_max, max); _inode_max = _inodes + max; _inode_top = _inodes + old_top; // restore _top } // Node_Stack is used to map nodes. Node* Node_Stack::find(uint idx) const { uint sz = size(); for (uint i=0; i < sz; i++) { if (idx == index_at(i) ) return node_at(i); } return NULL; } //============================================================================= uint TypeNode::size_of() const { return sizeof(*this); } #ifndef PRODUCT void TypeNode::dump_spec(outputStream *st) const { if( !Verbose && !WizardMode ) { // standard dump does this in Verbose and WizardMode st->print(" #"); _type->dump_on(st); } } #endif uint TypeNode::hash() const { return Node::hash() + _type->hash(); } uint TypeNode::cmp( const Node &n ) const { return !Type::cmp( _type, ((TypeNode&)n)._type ); } const Type *TypeNode::bottom_type() const { return _type; } const Type *TypeNode::Value( PhaseTransform * ) const { return _type; } //------------------------------ideal_reg-------------------------------------- uint TypeNode::ideal_reg() const { return _type->ideal_reg(); }