eb85b8da32
Reviewed-by: chagedorn, kvn
2129 lines
74 KiB
C++
2129 lines
74 KiB
C++
/*
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* Copyright (c) 1997, 2020, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*
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*/
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#include "precompiled.hpp"
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#include "gc/shared/barrierSet.hpp"
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#include "gc/shared/c2/barrierSetC2.hpp"
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#include "memory/allocation.inline.hpp"
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#include "memory/resourceArea.hpp"
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#include "opto/block.hpp"
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#include "opto/callnode.hpp"
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#include "opto/castnode.hpp"
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#include "opto/cfgnode.hpp"
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#include "opto/idealGraphPrinter.hpp"
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#include "opto/loopnode.hpp"
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#include "opto/machnode.hpp"
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#include "opto/opcodes.hpp"
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#include "opto/phaseX.hpp"
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#include "opto/regalloc.hpp"
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#include "opto/rootnode.hpp"
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#include "utilities/macros.hpp"
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#include "utilities/powerOfTwo.hpp"
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//=============================================================================
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#define NODE_HASH_MINIMUM_SIZE 255
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//------------------------------NodeHash---------------------------------------
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NodeHash::NodeHash(uint est_max_size) :
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_a(Thread::current()->resource_area()),
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_max( round_up(est_max_size < NODE_HASH_MINIMUM_SIZE ? NODE_HASH_MINIMUM_SIZE : est_max_size) ),
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_inserts(0), _insert_limit( insert_limit() ),
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_table( NEW_ARENA_ARRAY( _a , Node* , _max ) ) // (Node**)_a->Amalloc(_max * sizeof(Node*)) ),
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#ifndef PRODUCT
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, _grows(0),_look_probes(0), _lookup_hits(0), _lookup_misses(0),
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_insert_probes(0), _delete_probes(0), _delete_hits(0), _delete_misses(0),
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_total_inserts(0), _total_insert_probes(0)
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#endif
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{
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// _sentinel must be in the current node space
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_sentinel = new ProjNode(NULL, TypeFunc::Control);
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memset(_table,0,sizeof(Node*)*_max);
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}
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//------------------------------NodeHash---------------------------------------
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NodeHash::NodeHash(Arena *arena, uint est_max_size) :
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_a(arena),
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_max( round_up(est_max_size < NODE_HASH_MINIMUM_SIZE ? NODE_HASH_MINIMUM_SIZE : est_max_size) ),
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_inserts(0), _insert_limit( insert_limit() ),
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_table( NEW_ARENA_ARRAY( _a , Node* , _max ) )
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#ifndef PRODUCT
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, _grows(0),_look_probes(0), _lookup_hits(0), _lookup_misses(0),
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_insert_probes(0), _delete_probes(0), _delete_hits(0), _delete_misses(0),
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_total_inserts(0), _total_insert_probes(0)
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#endif
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{
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// _sentinel must be in the current node space
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_sentinel = new ProjNode(NULL, TypeFunc::Control);
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memset(_table,0,sizeof(Node*)*_max);
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}
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//------------------------------NodeHash---------------------------------------
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NodeHash::NodeHash(NodeHash *nh) {
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debug_only(_table = (Node**)badAddress); // interact correctly w/ operator=
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// just copy in all the fields
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*this = *nh;
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// nh->_sentinel must be in the current node space
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}
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void NodeHash::replace_with(NodeHash *nh) {
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debug_only(_table = (Node**)badAddress); // interact correctly w/ operator=
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// just copy in all the fields
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*this = *nh;
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// nh->_sentinel must be in the current node space
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}
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//------------------------------hash_find--------------------------------------
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// Find in hash table
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Node *NodeHash::hash_find( const Node *n ) {
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// ((Node*)n)->set_hash( n->hash() );
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uint hash = n->hash();
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if (hash == Node::NO_HASH) {
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NOT_PRODUCT( _lookup_misses++ );
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return NULL;
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}
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uint key = hash & (_max-1);
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uint stride = key | 0x01;
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NOT_PRODUCT( _look_probes++ );
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Node *k = _table[key]; // Get hashed value
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if( !k ) { // ?Miss?
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NOT_PRODUCT( _lookup_misses++ );
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return NULL; // Miss!
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}
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int op = n->Opcode();
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uint req = n->req();
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while( 1 ) { // While probing hash table
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if( k->req() == req && // Same count of inputs
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k->Opcode() == op ) { // Same Opcode
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for( uint i=0; i<req; i++ )
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if( n->in(i)!=k->in(i)) // Different inputs?
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goto collision; // "goto" is a speed hack...
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if( n->cmp(*k) ) { // Check for any special bits
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NOT_PRODUCT( _lookup_hits++ );
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return k; // Hit!
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}
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}
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collision:
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NOT_PRODUCT( _look_probes++ );
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key = (key + stride/*7*/) & (_max-1); // Stride through table with relative prime
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k = _table[key]; // Get hashed value
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if( !k ) { // ?Miss?
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NOT_PRODUCT( _lookup_misses++ );
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return NULL; // Miss!
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}
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}
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ShouldNotReachHere();
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return NULL;
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}
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//------------------------------hash_find_insert-------------------------------
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// Find in hash table, insert if not already present
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// Used to preserve unique entries in hash table
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Node *NodeHash::hash_find_insert( Node *n ) {
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// n->set_hash( );
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uint hash = n->hash();
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if (hash == Node::NO_HASH) {
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NOT_PRODUCT( _lookup_misses++ );
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return NULL;
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}
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uint key = hash & (_max-1);
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uint stride = key | 0x01; // stride must be relatively prime to table siz
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uint first_sentinel = 0; // replace a sentinel if seen.
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NOT_PRODUCT( _look_probes++ );
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Node *k = _table[key]; // Get hashed value
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if( !k ) { // ?Miss?
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NOT_PRODUCT( _lookup_misses++ );
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_table[key] = n; // Insert into table!
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debug_only(n->enter_hash_lock()); // Lock down the node while in the table.
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check_grow(); // Grow table if insert hit limit
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return NULL; // Miss!
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}
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else if( k == _sentinel ) {
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first_sentinel = key; // Can insert here
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}
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int op = n->Opcode();
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uint req = n->req();
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while( 1 ) { // While probing hash table
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if( k->req() == req && // Same count of inputs
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k->Opcode() == op ) { // Same Opcode
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for( uint i=0; i<req; i++ )
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if( n->in(i)!=k->in(i)) // Different inputs?
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goto collision; // "goto" is a speed hack...
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if( n->cmp(*k) ) { // Check for any special bits
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NOT_PRODUCT( _lookup_hits++ );
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return k; // Hit!
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}
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}
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collision:
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NOT_PRODUCT( _look_probes++ );
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key = (key + stride) & (_max-1); // Stride through table w/ relative prime
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k = _table[key]; // Get hashed value
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if( !k ) { // ?Miss?
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NOT_PRODUCT( _lookup_misses++ );
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key = (first_sentinel == 0) ? key : first_sentinel; // ?saw sentinel?
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_table[key] = n; // Insert into table!
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debug_only(n->enter_hash_lock()); // Lock down the node while in the table.
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check_grow(); // Grow table if insert hit limit
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return NULL; // Miss!
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}
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else if( first_sentinel == 0 && k == _sentinel ) {
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first_sentinel = key; // Can insert here
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}
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}
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ShouldNotReachHere();
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return NULL;
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}
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//------------------------------hash_insert------------------------------------
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// Insert into hash table
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void NodeHash::hash_insert( Node *n ) {
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// // "conflict" comments -- print nodes that conflict
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// bool conflict = false;
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// n->set_hash();
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uint hash = n->hash();
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if (hash == Node::NO_HASH) {
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return;
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}
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check_grow();
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uint key = hash & (_max-1);
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uint stride = key | 0x01;
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while( 1 ) { // While probing hash table
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NOT_PRODUCT( _insert_probes++ );
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Node *k = _table[key]; // Get hashed value
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if( !k || (k == _sentinel) ) break; // Found a slot
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assert( k != n, "already inserted" );
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// if( PrintCompilation && PrintOptoStatistics && Verbose ) { tty->print(" conflict: "); k->dump(); conflict = true; }
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key = (key + stride) & (_max-1); // Stride through table w/ relative prime
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}
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_table[key] = n; // Insert into table!
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debug_only(n->enter_hash_lock()); // Lock down the node while in the table.
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// if( conflict ) { n->dump(); }
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}
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//------------------------------hash_delete------------------------------------
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// Replace in hash table with sentinel
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bool NodeHash::hash_delete( const Node *n ) {
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Node *k;
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uint hash = n->hash();
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if (hash == Node::NO_HASH) {
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NOT_PRODUCT( _delete_misses++ );
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return false;
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}
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uint key = hash & (_max-1);
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uint stride = key | 0x01;
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debug_only( uint counter = 0; );
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for( ; /* (k != NULL) && (k != _sentinel) */; ) {
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debug_only( counter++ );
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NOT_PRODUCT( _delete_probes++ );
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k = _table[key]; // Get hashed value
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if( !k ) { // Miss?
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NOT_PRODUCT( _delete_misses++ );
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return false; // Miss! Not in chain
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}
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else if( n == k ) {
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NOT_PRODUCT( _delete_hits++ );
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_table[key] = _sentinel; // Hit! Label as deleted entry
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debug_only(((Node*)n)->exit_hash_lock()); // Unlock the node upon removal from table.
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return true;
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}
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else {
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// collision: move through table with prime offset
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key = (key + stride/*7*/) & (_max-1);
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assert( counter <= _insert_limit, "Cycle in hash-table");
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}
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}
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ShouldNotReachHere();
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return false;
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}
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//------------------------------round_up---------------------------------------
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// Round up to nearest power of 2
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uint NodeHash::round_up(uint x) {
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x += (x >> 2); // Add 25% slop
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return MAX2(16U, round_up_power_of_2(x));
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}
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//------------------------------grow-------------------------------------------
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// Grow _table to next power of 2 and insert old entries
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void NodeHash::grow() {
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// Record old state
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uint old_max = _max;
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Node **old_table = _table;
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// Construct new table with twice the space
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#ifndef PRODUCT
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_grows++;
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_total_inserts += _inserts;
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_total_insert_probes += _insert_probes;
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_insert_probes = 0;
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#endif
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_inserts = 0;
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_max = _max << 1;
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_table = NEW_ARENA_ARRAY( _a , Node* , _max ); // (Node**)_a->Amalloc( _max * sizeof(Node*) );
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memset(_table,0,sizeof(Node*)*_max);
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_insert_limit = insert_limit();
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// Insert old entries into the new table
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for( uint i = 0; i < old_max; i++ ) {
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Node *m = *old_table++;
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if( !m || m == _sentinel ) continue;
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debug_only(m->exit_hash_lock()); // Unlock the node upon removal from old table.
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hash_insert(m);
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}
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}
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//------------------------------clear------------------------------------------
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// Clear all entries in _table to NULL but keep storage
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void NodeHash::clear() {
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#ifdef ASSERT
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// Unlock all nodes upon removal from table.
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for (uint i = 0; i < _max; i++) {
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Node* n = _table[i];
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if (!n || n == _sentinel) continue;
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n->exit_hash_lock();
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}
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#endif
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memset( _table, 0, _max * sizeof(Node*) );
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}
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//-----------------------remove_useless_nodes----------------------------------
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// Remove useless nodes from value table,
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// implementation does not depend on hash function
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void NodeHash::remove_useless_nodes(VectorSet &useful) {
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// Dead nodes in the hash table inherited from GVN should not replace
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// existing nodes, remove dead nodes.
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uint max = size();
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Node *sentinel_node = sentinel();
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for( uint i = 0; i < max; ++i ) {
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Node *n = at(i);
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if(n != NULL && n != sentinel_node && !useful.test(n->_idx)) {
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debug_only(n->exit_hash_lock()); // Unlock the node when removed
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_table[i] = sentinel_node; // Replace with placeholder
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}
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}
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}
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void NodeHash::check_no_speculative_types() {
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#ifdef ASSERT
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uint max = size();
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Node *sentinel_node = sentinel();
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for (uint i = 0; i < max; ++i) {
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Node *n = at(i);
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if(n != NULL && n != sentinel_node && n->is_Type() && n->outcnt() > 0) {
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TypeNode* tn = n->as_Type();
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const Type* t = tn->type();
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const Type* t_no_spec = t->remove_speculative();
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assert(t == t_no_spec, "dead node in hash table or missed node during speculative cleanup");
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}
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}
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#endif
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}
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#ifndef PRODUCT
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//------------------------------dump-------------------------------------------
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// Dump statistics for the hash table
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void NodeHash::dump() {
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_total_inserts += _inserts;
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_total_insert_probes += _insert_probes;
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if (PrintCompilation && PrintOptoStatistics && Verbose && (_inserts > 0)) {
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if (WizardMode) {
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for (uint i=0; i<_max; i++) {
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if (_table[i])
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tty->print("%d/%d/%d ",i,_table[i]->hash()&(_max-1),_table[i]->_idx);
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}
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}
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tty->print("\nGVN Hash stats: %d grows to %d max_size\n", _grows, _max);
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tty->print(" %d/%d (%8.1f%% full)\n", _inserts, _max, (double)_inserts/_max*100.0);
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tty->print(" %dp/(%dh+%dm) (%8.2f probes/lookup)\n", _look_probes, _lookup_hits, _lookup_misses, (double)_look_probes/(_lookup_hits+_lookup_misses));
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tty->print(" %dp/%di (%8.2f probes/insert)\n", _total_insert_probes, _total_inserts, (double)_total_insert_probes/_total_inserts);
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// sentinels increase lookup cost, but not insert cost
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assert((_lookup_misses+_lookup_hits)*4+100 >= _look_probes, "bad hash function");
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assert( _inserts+(_inserts>>3) < _max, "table too full" );
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assert( _inserts*3+100 >= _insert_probes, "bad hash function" );
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}
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}
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Node *NodeHash::find_index(uint idx) { // For debugging
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// Find an entry by its index value
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for( uint i = 0; i < _max; i++ ) {
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Node *m = _table[i];
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if( !m || m == _sentinel ) continue;
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if( m->_idx == (uint)idx ) return m;
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}
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return NULL;
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}
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#endif
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#ifdef ASSERT
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NodeHash::~NodeHash() {
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// Unlock all nodes upon destruction of table.
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if (_table != (Node**)badAddress) clear();
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}
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void NodeHash::operator=(const NodeHash& nh) {
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// Unlock all nodes upon replacement of table.
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if (&nh == this) return;
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if (_table != (Node**)badAddress) clear();
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memcpy((void*)this, (void*)&nh, sizeof(*this));
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// Do not increment hash_lock counts again.
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// Instead, be sure we never again use the source table.
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((NodeHash*)&nh)->_table = (Node**)badAddress;
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}
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#endif
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//=============================================================================
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//------------------------------PhaseRemoveUseless-----------------------------
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// 1) Use a breadthfirst walk to collect useful nodes reachable from root.
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PhaseRemoveUseless::PhaseRemoveUseless(PhaseGVN* gvn, Unique_Node_List* worklist, PhaseNumber phase_num) : Phase(phase_num) {
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// Implementation requires 'UseLoopSafepoints == true' and an edge from root
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// to each SafePointNode at a backward branch. Inserted in add_safepoint().
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if( !UseLoopSafepoints || !OptoRemoveUseless ) return;
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// Identify nodes that are reachable from below, useful.
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C->identify_useful_nodes(_useful);
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// Update dead node list
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C->update_dead_node_list(_useful);
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// Remove all useless nodes from PhaseValues' recorded types
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// Must be done before disconnecting nodes to preserve hash-table-invariant
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gvn->remove_useless_nodes(_useful.member_set());
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// Remove all useless nodes from future worklist
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worklist->remove_useless_nodes(_useful.member_set());
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// Disconnect 'useless' nodes that are adjacent to useful nodes
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C->remove_useless_nodes(_useful);
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}
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//=============================================================================
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//------------------------------PhaseRenumberLive------------------------------
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// First, remove useless nodes (equivalent to identifying live nodes).
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// Then, renumber live nodes.
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//
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// The set of live nodes is returned by PhaseRemoveUseless in the _useful structure.
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// If the number of live nodes is 'x' (where 'x' == _useful.size()), then the
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// PhaseRenumberLive updates the node ID of each node (the _idx field) with a unique
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// value in the range [0, x).
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//
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// At the end of the PhaseRenumberLive phase, the compiler's count of unique nodes is
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// updated to 'x' and the list of dead nodes is reset (as there are no dead nodes).
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//
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// The PhaseRenumberLive phase updates two data structures with the new node IDs.
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// (1) The worklist is used by the PhaseIterGVN phase to identify nodes that must be
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// processed. A new worklist (with the updated node IDs) is returned in 'new_worklist'.
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// 'worklist' is cleared upon returning.
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// (2) Type information (the field PhaseGVN::_types) maps type information to each
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// node ID. The mapping is updated to use the new node IDs as well. Updated type
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// information is returned in PhaseGVN::_types.
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//
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// The PhaseRenumberLive phase does not preserve the order of elements in the worklist.
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//
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// Other data structures used by the compiler are not updated. The hash table for value
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// numbering (the field PhaseGVN::_table) is not updated because computing the hash
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// values is not based on node IDs. The field PhaseGVN::_nodes is not updated either
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// because it is empty wherever PhaseRenumberLive is used.
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PhaseRenumberLive::PhaseRenumberLive(PhaseGVN* gvn,
|
|
Unique_Node_List* worklist, Unique_Node_List* new_worklist,
|
|
PhaseNumber phase_num) :
|
|
PhaseRemoveUseless(gvn, worklist, Remove_Useless_And_Renumber_Live),
|
|
_new_type_array(C->comp_arena()),
|
|
_old2new_map(C->unique(), C->unique(), -1),
|
|
_is_pass_finished(false),
|
|
_live_node_count(C->live_nodes())
|
|
{
|
|
assert(RenumberLiveNodes, "RenumberLiveNodes must be set to true for node renumbering to take place");
|
|
assert(C->live_nodes() == _useful.size(), "the number of live nodes must match the number of useful nodes");
|
|
assert(gvn->nodes_size() == 0, "GVN must not contain any nodes at this point");
|
|
assert(_delayed.size() == 0, "should be empty");
|
|
|
|
uint worklist_size = worklist->size();
|
|
|
|
// Iterate over the set of live nodes.
|
|
for (uint current_idx = 0; current_idx < _useful.size(); current_idx++) {
|
|
Node* n = _useful.at(current_idx);
|
|
|
|
bool in_worklist = false;
|
|
if (worklist->member(n)) {
|
|
in_worklist = true;
|
|
}
|
|
|
|
const Type* type = gvn->type_or_null(n);
|
|
_new_type_array.map(current_idx, type);
|
|
|
|
assert(_old2new_map.at(n->_idx) == -1, "already seen");
|
|
_old2new_map.at_put(n->_idx, current_idx);
|
|
|
|
n->set_idx(current_idx); // Update node ID.
|
|
|
|
if (in_worklist) {
|
|
new_worklist->push(n);
|
|
}
|
|
|
|
if (update_embedded_ids(n) < 0) {
|
|
_delayed.push(n); // has embedded IDs; handle later
|
|
}
|
|
}
|
|
|
|
assert(worklist_size == new_worklist->size(), "the new worklist must have the same size as the original worklist");
|
|
assert(_live_node_count == _useful.size(), "all live nodes must be processed");
|
|
|
|
_is_pass_finished = true; // pass finished; safe to process delayed updates
|
|
|
|
while (_delayed.size() > 0) {
|
|
Node* n = _delayed.pop();
|
|
int no_of_updates = update_embedded_ids(n);
|
|
assert(no_of_updates > 0, "should be updated");
|
|
}
|
|
|
|
// Replace the compiler's type information with the updated type information.
|
|
gvn->replace_types(_new_type_array);
|
|
|
|
// Update the unique node count of the compilation to the number of currently live nodes.
|
|
C->set_unique(_live_node_count);
|
|
|
|
// Set the dead node count to 0 and reset dead node list.
|
|
C->reset_dead_node_list();
|
|
|
|
// Clear the original worklist
|
|
worklist->clear();
|
|
}
|
|
|
|
int PhaseRenumberLive::new_index(int old_idx) {
|
|
assert(_is_pass_finished, "not finished");
|
|
if (_old2new_map.at(old_idx) == -1) { // absent
|
|
// Allocate a placeholder to preserve uniqueness
|
|
_old2new_map.at_put(old_idx, _live_node_count);
|
|
_live_node_count++;
|
|
}
|
|
return _old2new_map.at(old_idx);
|
|
}
|
|
|
|
int PhaseRenumberLive::update_embedded_ids(Node* n) {
|
|
int no_of_updates = 0;
|
|
if (n->is_Phi()) {
|
|
PhiNode* phi = n->as_Phi();
|
|
if (phi->_inst_id != -1) {
|
|
if (!_is_pass_finished) {
|
|
return -1; // delay
|
|
}
|
|
int new_idx = new_index(phi->_inst_id);
|
|
assert(new_idx != -1, "");
|
|
phi->_inst_id = new_idx;
|
|
no_of_updates++;
|
|
}
|
|
if (phi->_inst_mem_id != -1) {
|
|
if (!_is_pass_finished) {
|
|
return -1; // delay
|
|
}
|
|
int new_idx = new_index(phi->_inst_mem_id);
|
|
assert(new_idx != -1, "");
|
|
phi->_inst_mem_id = new_idx;
|
|
no_of_updates++;
|
|
}
|
|
}
|
|
|
|
const Type* type = _new_type_array.fast_lookup(n->_idx);
|
|
if (type != NULL && type->isa_oopptr() && type->is_oopptr()->is_known_instance()) {
|
|
if (!_is_pass_finished) {
|
|
return -1; // delay
|
|
}
|
|
int old_idx = type->is_oopptr()->instance_id();
|
|
int new_idx = new_index(old_idx);
|
|
const Type* new_type = type->is_oopptr()->with_instance_id(new_idx);
|
|
_new_type_array.map(n->_idx, new_type);
|
|
no_of_updates++;
|
|
}
|
|
|
|
return no_of_updates;
|
|
}
|
|
|
|
//=============================================================================
|
|
//------------------------------PhaseTransform---------------------------------
|
|
PhaseTransform::PhaseTransform( PhaseNumber pnum ) : Phase(pnum),
|
|
_arena(Thread::current()->resource_area()),
|
|
_nodes(_arena),
|
|
_types(_arena)
|
|
{
|
|
init_con_caches();
|
|
#ifndef PRODUCT
|
|
clear_progress();
|
|
clear_transforms();
|
|
set_allow_progress(true);
|
|
#endif
|
|
// Force allocation for currently existing nodes
|
|
_types.map(C->unique(), NULL);
|
|
}
|
|
|
|
//------------------------------PhaseTransform---------------------------------
|
|
PhaseTransform::PhaseTransform( Arena *arena, PhaseNumber pnum ) : Phase(pnum),
|
|
_arena(arena),
|
|
_nodes(arena),
|
|
_types(arena)
|
|
{
|
|
init_con_caches();
|
|
#ifndef PRODUCT
|
|
clear_progress();
|
|
clear_transforms();
|
|
set_allow_progress(true);
|
|
#endif
|
|
// Force allocation for currently existing nodes
|
|
_types.map(C->unique(), NULL);
|
|
}
|
|
|
|
//------------------------------PhaseTransform---------------------------------
|
|
// Initialize with previously generated type information
|
|
PhaseTransform::PhaseTransform( PhaseTransform *pt, PhaseNumber pnum ) : Phase(pnum),
|
|
_arena(pt->_arena),
|
|
_nodes(pt->_nodes),
|
|
_types(pt->_types)
|
|
{
|
|
init_con_caches();
|
|
#ifndef PRODUCT
|
|
clear_progress();
|
|
clear_transforms();
|
|
set_allow_progress(true);
|
|
#endif
|
|
}
|
|
|
|
void PhaseTransform::init_con_caches() {
|
|
memset(_icons,0,sizeof(_icons));
|
|
memset(_lcons,0,sizeof(_lcons));
|
|
memset(_zcons,0,sizeof(_zcons));
|
|
}
|
|
|
|
|
|
//--------------------------------find_int_type--------------------------------
|
|
const TypeInt* PhaseTransform::find_int_type(Node* n) {
|
|
if (n == NULL) return NULL;
|
|
// Call type_or_null(n) to determine node's type since we might be in
|
|
// parse phase and call n->Value() may return wrong type.
|
|
// (For example, a phi node at the beginning of loop parsing is not ready.)
|
|
const Type* t = type_or_null(n);
|
|
if (t == NULL) return NULL;
|
|
return t->isa_int();
|
|
}
|
|
|
|
|
|
//-------------------------------find_long_type--------------------------------
|
|
const TypeLong* PhaseTransform::find_long_type(Node* n) {
|
|
if (n == NULL) return NULL;
|
|
// (See comment above on type_or_null.)
|
|
const Type* t = type_or_null(n);
|
|
if (t == NULL) return NULL;
|
|
return t->isa_long();
|
|
}
|
|
|
|
|
|
#ifndef PRODUCT
|
|
void PhaseTransform::dump_old2new_map() const {
|
|
_nodes.dump();
|
|
}
|
|
|
|
void PhaseTransform::dump_new( uint nidx ) const {
|
|
for( uint i=0; i<_nodes.Size(); i++ )
|
|
if( _nodes[i] && _nodes[i]->_idx == nidx ) {
|
|
_nodes[i]->dump();
|
|
tty->cr();
|
|
tty->print_cr("Old index= %d",i);
|
|
return;
|
|
}
|
|
tty->print_cr("Node %d not found in the new indices", nidx);
|
|
}
|
|
|
|
//------------------------------dump_types-------------------------------------
|
|
void PhaseTransform::dump_types( ) const {
|
|
_types.dump();
|
|
}
|
|
|
|
//------------------------------dump_nodes_and_types---------------------------
|
|
void PhaseTransform::dump_nodes_and_types(const Node* root, uint depth, bool only_ctrl) {
|
|
VectorSet visited;
|
|
dump_nodes_and_types_recur(root, depth, only_ctrl, visited);
|
|
}
|
|
|
|
//------------------------------dump_nodes_and_types_recur---------------------
|
|
void PhaseTransform::dump_nodes_and_types_recur( const Node *n, uint depth, bool only_ctrl, VectorSet &visited) {
|
|
if( !n ) return;
|
|
if( depth == 0 ) return;
|
|
if( visited.test_set(n->_idx) ) return;
|
|
for( uint i=0; i<n->len(); i++ ) {
|
|
if( only_ctrl && !(n->is_Region()) && i != TypeFunc::Control ) continue;
|
|
dump_nodes_and_types_recur( n->in(i), depth-1, only_ctrl, visited );
|
|
}
|
|
n->dump();
|
|
if (type_or_null(n) != NULL) {
|
|
tty->print(" "); type(n)->dump(); tty->cr();
|
|
}
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
//=============================================================================
|
|
//------------------------------PhaseValues------------------------------------
|
|
// Set minimum table size to "255"
|
|
PhaseValues::PhaseValues( Arena *arena, uint est_max_size ) : PhaseTransform(arena, GVN), _table(arena, est_max_size) {
|
|
NOT_PRODUCT( clear_new_values(); )
|
|
}
|
|
|
|
//------------------------------PhaseValues------------------------------------
|
|
// Set minimum table size to "255"
|
|
PhaseValues::PhaseValues( PhaseValues *ptv ) : PhaseTransform( ptv, GVN ),
|
|
_table(&ptv->_table) {
|
|
NOT_PRODUCT( clear_new_values(); )
|
|
}
|
|
|
|
//------------------------------~PhaseValues-----------------------------------
|
|
#ifndef PRODUCT
|
|
PhaseValues::~PhaseValues() {
|
|
_table.dump();
|
|
|
|
// Statistics for value progress and efficiency
|
|
if( PrintCompilation && Verbose && WizardMode ) {
|
|
tty->print("\n%sValues: %d nodes ---> %d/%d (%d)",
|
|
is_IterGVN() ? "Iter" : " ", C->unique(), made_progress(), made_transforms(), made_new_values());
|
|
if( made_transforms() != 0 ) {
|
|
tty->print_cr(" ratio %f", made_progress()/(float)made_transforms() );
|
|
} else {
|
|
tty->cr();
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
//------------------------------makecon----------------------------------------
|
|
ConNode* PhaseTransform::makecon(const Type *t) {
|
|
assert(t->singleton(), "must be a constant");
|
|
assert(!t->empty() || t == Type::TOP, "must not be vacuous range");
|
|
switch (t->base()) { // fast paths
|
|
case Type::Half:
|
|
case Type::Top: return (ConNode*) C->top();
|
|
case Type::Int: return intcon( t->is_int()->get_con() );
|
|
case Type::Long: return longcon( t->is_long()->get_con() );
|
|
default: break;
|
|
}
|
|
if (t->is_zero_type())
|
|
return zerocon(t->basic_type());
|
|
return uncached_makecon(t);
|
|
}
|
|
|
|
//--------------------------uncached_makecon-----------------------------------
|
|
// Make an idealized constant - one of ConINode, ConPNode, etc.
|
|
ConNode* PhaseValues::uncached_makecon(const Type *t) {
|
|
assert(t->singleton(), "must be a constant");
|
|
ConNode* x = ConNode::make(t);
|
|
ConNode* k = (ConNode*)hash_find_insert(x); // Value numbering
|
|
if (k == NULL) {
|
|
set_type(x, t); // Missed, provide type mapping
|
|
GrowableArray<Node_Notes*>* nna = C->node_note_array();
|
|
if (nna != NULL) {
|
|
Node_Notes* loc = C->locate_node_notes(nna, x->_idx, true);
|
|
loc->clear(); // do not put debug info on constants
|
|
}
|
|
} else {
|
|
x->destruct(this); // Hit, destroy duplicate constant
|
|
x = k; // use existing constant
|
|
}
|
|
return x;
|
|
}
|
|
|
|
//------------------------------intcon-----------------------------------------
|
|
// Fast integer constant. Same as "transform(new ConINode(TypeInt::make(i)))"
|
|
ConINode* PhaseTransform::intcon(jint i) {
|
|
// Small integer? Check cache! Check that cached node is not dead
|
|
if (i >= _icon_min && i <= _icon_max) {
|
|
ConINode* icon = _icons[i-_icon_min];
|
|
if (icon != NULL && icon->in(TypeFunc::Control) != NULL)
|
|
return icon;
|
|
}
|
|
ConINode* icon = (ConINode*) uncached_makecon(TypeInt::make(i));
|
|
assert(icon->is_Con(), "");
|
|
if (i >= _icon_min && i <= _icon_max)
|
|
_icons[i-_icon_min] = icon; // Cache small integers
|
|
return icon;
|
|
}
|
|
|
|
//------------------------------longcon----------------------------------------
|
|
// Fast long constant.
|
|
ConLNode* PhaseTransform::longcon(jlong l) {
|
|
// Small integer? Check cache! Check that cached node is not dead
|
|
if (l >= _lcon_min && l <= _lcon_max) {
|
|
ConLNode* lcon = _lcons[l-_lcon_min];
|
|
if (lcon != NULL && lcon->in(TypeFunc::Control) != NULL)
|
|
return lcon;
|
|
}
|
|
ConLNode* lcon = (ConLNode*) uncached_makecon(TypeLong::make(l));
|
|
assert(lcon->is_Con(), "");
|
|
if (l >= _lcon_min && l <= _lcon_max)
|
|
_lcons[l-_lcon_min] = lcon; // Cache small integers
|
|
return lcon;
|
|
}
|
|
|
|
//------------------------------zerocon-----------------------------------------
|
|
// Fast zero or null constant. Same as "transform(ConNode::make(Type::get_zero_type(bt)))"
|
|
ConNode* PhaseTransform::zerocon(BasicType bt) {
|
|
assert((uint)bt <= _zcon_max, "domain check");
|
|
ConNode* zcon = _zcons[bt];
|
|
if (zcon != NULL && zcon->in(TypeFunc::Control) != NULL)
|
|
return zcon;
|
|
zcon = (ConNode*) uncached_makecon(Type::get_zero_type(bt));
|
|
_zcons[bt] = zcon;
|
|
return zcon;
|
|
}
|
|
|
|
|
|
|
|
//=============================================================================
|
|
Node* PhaseGVN::apply_ideal(Node* k, bool can_reshape) {
|
|
Node* i = BarrierSet::barrier_set()->barrier_set_c2()->ideal_node(this, k, can_reshape);
|
|
if (i == NULL) {
|
|
i = k->Ideal(this, can_reshape);
|
|
}
|
|
return i;
|
|
}
|
|
|
|
//------------------------------transform--------------------------------------
|
|
// Return a node which computes the same function as this node, but in a
|
|
// faster or cheaper fashion.
|
|
Node *PhaseGVN::transform( Node *n ) {
|
|
return transform_no_reclaim(n);
|
|
}
|
|
|
|
//------------------------------transform--------------------------------------
|
|
// Return a node which computes the same function as this node, but
|
|
// in a faster or cheaper fashion.
|
|
Node *PhaseGVN::transform_no_reclaim( Node *n ) {
|
|
NOT_PRODUCT( set_transforms(); )
|
|
|
|
// Apply the Ideal call in a loop until it no longer applies
|
|
Node *k = n;
|
|
NOT_PRODUCT( uint loop_count = 0; )
|
|
while( 1 ) {
|
|
Node *i = apply_ideal(k, /*can_reshape=*/false);
|
|
if( !i ) break;
|
|
assert( i->_idx >= k->_idx, "Idealize should return new nodes, use Identity to return old nodes" );
|
|
k = i;
|
|
assert(loop_count++ < K, "infinite loop in PhaseGVN::transform");
|
|
}
|
|
NOT_PRODUCT( if( loop_count != 0 ) { set_progress(); } )
|
|
|
|
|
|
// If brand new node, make space in type array.
|
|
ensure_type_or_null(k);
|
|
|
|
// Since I just called 'Value' to compute the set of run-time values
|
|
// for this Node, and 'Value' is non-local (and therefore expensive) I'll
|
|
// cache Value. Later requests for the local phase->type of this Node can
|
|
// use the cached Value instead of suffering with 'bottom_type'.
|
|
const Type *t = k->Value(this); // Get runtime Value set
|
|
assert(t != NULL, "value sanity");
|
|
if (type_or_null(k) != t) {
|
|
#ifndef PRODUCT
|
|
// Do not count initial visit to node as a transformation
|
|
if (type_or_null(k) == NULL) {
|
|
inc_new_values();
|
|
set_progress();
|
|
}
|
|
#endif
|
|
set_type(k, t);
|
|
// If k is a TypeNode, capture any more-precise type permanently into Node
|
|
k->raise_bottom_type(t);
|
|
}
|
|
|
|
if( t->singleton() && !k->is_Con() ) {
|
|
NOT_PRODUCT( set_progress(); )
|
|
return makecon(t); // Turn into a constant
|
|
}
|
|
|
|
// Now check for Identities
|
|
Node *i = k->Identity(this); // Look for a nearby replacement
|
|
if( i != k ) { // Found? Return replacement!
|
|
NOT_PRODUCT( set_progress(); )
|
|
return i;
|
|
}
|
|
|
|
// Global Value Numbering
|
|
i = hash_find_insert(k); // Insert if new
|
|
if( i && (i != k) ) {
|
|
// Return the pre-existing node
|
|
NOT_PRODUCT( set_progress(); )
|
|
return i;
|
|
}
|
|
|
|
// Return Idealized original
|
|
return k;
|
|
}
|
|
|
|
bool PhaseGVN::is_dominator_helper(Node *d, Node *n, bool linear_only) {
|
|
if (d->is_top() || (d->is_Proj() && d->in(0)->is_top())) {
|
|
return false;
|
|
}
|
|
if (n->is_top() || (n->is_Proj() && n->in(0)->is_top())) {
|
|
return false;
|
|
}
|
|
assert(d->is_CFG() && n->is_CFG(), "must have CFG nodes");
|
|
int i = 0;
|
|
while (d != n) {
|
|
n = IfNode::up_one_dom(n, linear_only);
|
|
i++;
|
|
if (n == NULL || i >= 100) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
#ifdef ASSERT
|
|
//------------------------------dead_loop_check--------------------------------
|
|
// Check for a simple dead loop when a data node references itself directly
|
|
// or through an other data node excluding cons and phis.
|
|
void PhaseGVN::dead_loop_check( Node *n ) {
|
|
// Phi may reference itself in a loop
|
|
if (n != NULL && !n->is_dead_loop_safe() && !n->is_CFG()) {
|
|
// Do 2 levels check and only data inputs.
|
|
bool no_dead_loop = true;
|
|
uint cnt = n->req();
|
|
for (uint i = 1; i < cnt && no_dead_loop; i++) {
|
|
Node *in = n->in(i);
|
|
if (in == n) {
|
|
no_dead_loop = false;
|
|
} else if (in != NULL && !in->is_dead_loop_safe()) {
|
|
uint icnt = in->req();
|
|
for (uint j = 1; j < icnt && no_dead_loop; j++) {
|
|
if (in->in(j) == n || in->in(j) == in)
|
|
no_dead_loop = false;
|
|
}
|
|
}
|
|
}
|
|
if (!no_dead_loop) n->dump(3);
|
|
assert(no_dead_loop, "dead loop detected");
|
|
}
|
|
}
|
|
#endif
|
|
|
|
//=============================================================================
|
|
//------------------------------PhaseIterGVN-----------------------------------
|
|
// Initialize with previous PhaseIterGVN info; used by PhaseCCP
|
|
PhaseIterGVN::PhaseIterGVN( PhaseIterGVN *igvn ) : PhaseGVN(igvn),
|
|
_delay_transform(igvn->_delay_transform),
|
|
_stack( igvn->_stack ),
|
|
_worklist( igvn->_worklist )
|
|
{
|
|
}
|
|
|
|
//------------------------------PhaseIterGVN-----------------------------------
|
|
// Initialize with previous PhaseGVN info from Parser
|
|
PhaseIterGVN::PhaseIterGVN( PhaseGVN *gvn ) : PhaseGVN(gvn),
|
|
_delay_transform(false),
|
|
// TODO: Before incremental inlining it was allocated only once and it was fine. Now that
|
|
// the constructor is used in incremental inlining, this consumes too much memory:
|
|
// _stack(C->live_nodes() >> 1),
|
|
// So, as a band-aid, we replace this by:
|
|
_stack(C->comp_arena(), 32),
|
|
_worklist(*C->for_igvn())
|
|
{
|
|
uint max;
|
|
|
|
// Dead nodes in the hash table inherited from GVN were not treated as
|
|
// roots during def-use info creation; hence they represent an invisible
|
|
// use. Clear them out.
|
|
max = _table.size();
|
|
for( uint i = 0; i < max; ++i ) {
|
|
Node *n = _table.at(i);
|
|
if(n != NULL && n != _table.sentinel() && n->outcnt() == 0) {
|
|
if( n->is_top() ) continue;
|
|
assert( false, "Parse::remove_useless_nodes missed this node");
|
|
hash_delete(n);
|
|
}
|
|
}
|
|
|
|
// Any Phis or Regions on the worklist probably had uses that could not
|
|
// make more progress because the uses were made while the Phis and Regions
|
|
// were in half-built states. Put all uses of Phis and Regions on worklist.
|
|
max = _worklist.size();
|
|
for( uint j = 0; j < max; j++ ) {
|
|
Node *n = _worklist.at(j);
|
|
uint uop = n->Opcode();
|
|
if( uop == Op_Phi || uop == Op_Region ||
|
|
n->is_Type() ||
|
|
n->is_Mem() )
|
|
add_users_to_worklist(n);
|
|
}
|
|
}
|
|
|
|
void PhaseIterGVN::shuffle_worklist() {
|
|
if (_worklist.size() < 2) return;
|
|
for (uint i = _worklist.size() - 1; i >= 1; i--) {
|
|
uint j = C->random() % (i + 1);
|
|
swap(_worklist.adr()[i], _worklist.adr()[j]);
|
|
}
|
|
}
|
|
|
|
#ifndef PRODUCT
|
|
void PhaseIterGVN::verify_step(Node* n) {
|
|
if (VerifyIterativeGVN) {
|
|
_verify_window[_verify_counter % _verify_window_size] = n;
|
|
++_verify_counter;
|
|
if (C->unique() < 1000 || 0 == _verify_counter % (C->unique() < 10000 ? 10 : 100)) {
|
|
++_verify_full_passes;
|
|
Node::verify(C->root(), -1);
|
|
}
|
|
for (int i = 0; i < _verify_window_size; i++) {
|
|
Node* n = _verify_window[i];
|
|
if (n == NULL) {
|
|
continue;
|
|
}
|
|
if (n->in(0) == NodeSentinel) { // xform_idom
|
|
_verify_window[i] = n->in(1);
|
|
--i;
|
|
continue;
|
|
}
|
|
// Typical fanout is 1-2, so this call visits about 6 nodes.
|
|
Node::verify(n, 4);
|
|
}
|
|
}
|
|
}
|
|
|
|
void PhaseIterGVN::trace_PhaseIterGVN(Node* n, Node* nn, const Type* oldtype) {
|
|
if (TraceIterativeGVN) {
|
|
uint wlsize = _worklist.size();
|
|
const Type* newtype = type_or_null(n);
|
|
if (nn != n) {
|
|
// print old node
|
|
tty->print("< ");
|
|
if (oldtype != newtype && oldtype != NULL) {
|
|
oldtype->dump();
|
|
}
|
|
do { tty->print("\t"); } while (tty->position() < 16);
|
|
tty->print("<");
|
|
n->dump();
|
|
}
|
|
if (oldtype != newtype || nn != n) {
|
|
// print new node and/or new type
|
|
if (oldtype == NULL) {
|
|
tty->print("* ");
|
|
} else if (nn != n) {
|
|
tty->print("> ");
|
|
} else {
|
|
tty->print("= ");
|
|
}
|
|
if (newtype == NULL) {
|
|
tty->print("null");
|
|
} else {
|
|
newtype->dump();
|
|
}
|
|
do { tty->print("\t"); } while (tty->position() < 16);
|
|
nn->dump();
|
|
}
|
|
if (Verbose && wlsize < _worklist.size()) {
|
|
tty->print(" Push {");
|
|
while (wlsize != _worklist.size()) {
|
|
Node* pushed = _worklist.at(wlsize++);
|
|
tty->print(" %d", pushed->_idx);
|
|
}
|
|
tty->print_cr(" }");
|
|
}
|
|
if (nn != n) {
|
|
// ignore n, it might be subsumed
|
|
verify_step((Node*) NULL);
|
|
}
|
|
}
|
|
}
|
|
|
|
void PhaseIterGVN::init_verifyPhaseIterGVN() {
|
|
_verify_counter = 0;
|
|
_verify_full_passes = 0;
|
|
for (int i = 0; i < _verify_window_size; i++) {
|
|
_verify_window[i] = NULL;
|
|
}
|
|
#ifdef ASSERT
|
|
// Verify that all modified nodes are on _worklist
|
|
Unique_Node_List* modified_list = C->modified_nodes();
|
|
while (modified_list != NULL && modified_list->size()) {
|
|
Node* n = modified_list->pop();
|
|
if (!n->is_Con() && !_worklist.member(n)) {
|
|
n->dump();
|
|
fatal("modified node is not on IGVN._worklist");
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
void PhaseIterGVN::verify_PhaseIterGVN() {
|
|
#ifdef ASSERT
|
|
// Verify nodes with changed inputs.
|
|
Unique_Node_List* modified_list = C->modified_nodes();
|
|
while (modified_list != NULL && modified_list->size()) {
|
|
Node* n = modified_list->pop();
|
|
if (!n->is_Con()) { // skip Con nodes
|
|
n->dump();
|
|
fatal("modified node was not processed by IGVN.transform_old()");
|
|
}
|
|
}
|
|
#endif
|
|
|
|
C->verify_graph_edges();
|
|
if (VerifyIterativeGVN && PrintOpto) {
|
|
if (_verify_counter == _verify_full_passes) {
|
|
tty->print_cr("VerifyIterativeGVN: %d transforms and verify passes",
|
|
(int) _verify_full_passes);
|
|
} else {
|
|
tty->print_cr("VerifyIterativeGVN: %d transforms, %d full verify passes",
|
|
(int) _verify_counter, (int) _verify_full_passes);
|
|
}
|
|
}
|
|
|
|
#ifdef ASSERT
|
|
while (modified_list->size()) {
|
|
Node* n = modified_list->pop();
|
|
n->dump();
|
|
assert(false, "VerifyIterativeGVN: new modified node was added");
|
|
}
|
|
#endif
|
|
}
|
|
#endif /* PRODUCT */
|
|
|
|
#ifdef ASSERT
|
|
/**
|
|
* Dumps information that can help to debug the problem. A debug
|
|
* build fails with an assert.
|
|
*/
|
|
void PhaseIterGVN::dump_infinite_loop_info(Node* n) {
|
|
n->dump(4);
|
|
_worklist.dump();
|
|
assert(false, "infinite loop in PhaseIterGVN::optimize");
|
|
}
|
|
|
|
/**
|
|
* Prints out information about IGVN if the 'verbose' option is used.
|
|
*/
|
|
void PhaseIterGVN::trace_PhaseIterGVN_verbose(Node* n, int num_processed) {
|
|
if (TraceIterativeGVN && Verbose) {
|
|
tty->print(" Pop ");
|
|
n->dump();
|
|
if ((num_processed % 100) == 0) {
|
|
_worklist.print_set();
|
|
}
|
|
}
|
|
}
|
|
#endif /* ASSERT */
|
|
|
|
void PhaseIterGVN::optimize() {
|
|
DEBUG_ONLY(uint num_processed = 0;)
|
|
NOT_PRODUCT(init_verifyPhaseIterGVN();)
|
|
if (StressIGVN) {
|
|
shuffle_worklist();
|
|
}
|
|
|
|
uint loop_count = 0;
|
|
// Pull from worklist and transform the node. If the node has changed,
|
|
// update edge info and put uses on worklist.
|
|
while(_worklist.size()) {
|
|
if (C->check_node_count(NodeLimitFudgeFactor * 2, "Out of nodes")) {
|
|
return;
|
|
}
|
|
Node* n = _worklist.pop();
|
|
if (++loop_count >= K * C->live_nodes()) {
|
|
DEBUG_ONLY(dump_infinite_loop_info(n);)
|
|
C->record_method_not_compilable("infinite loop in PhaseIterGVN::optimize");
|
|
return;
|
|
}
|
|
DEBUG_ONLY(trace_PhaseIterGVN_verbose(n, num_processed++);)
|
|
if (n->outcnt() != 0) {
|
|
NOT_PRODUCT(const Type* oldtype = type_or_null(n));
|
|
// Do the transformation
|
|
Node* nn = transform_old(n);
|
|
NOT_PRODUCT(trace_PhaseIterGVN(n, nn, oldtype);)
|
|
} else if (!n->is_top()) {
|
|
remove_dead_node(n);
|
|
}
|
|
}
|
|
NOT_PRODUCT(verify_PhaseIterGVN();)
|
|
}
|
|
|
|
|
|
/**
|
|
* Register a new node with the optimizer. Update the types array, the def-use
|
|
* info. Put on worklist.
|
|
*/
|
|
Node* PhaseIterGVN::register_new_node_with_optimizer(Node* n, Node* orig) {
|
|
set_type_bottom(n);
|
|
_worklist.push(n);
|
|
if (orig != NULL) C->copy_node_notes_to(n, orig);
|
|
return n;
|
|
}
|
|
|
|
//------------------------------transform--------------------------------------
|
|
// Non-recursive: idealize Node 'n' with respect to its inputs and its value
|
|
Node *PhaseIterGVN::transform( Node *n ) {
|
|
if (_delay_transform) {
|
|
// Register the node but don't optimize for now
|
|
register_new_node_with_optimizer(n);
|
|
return n;
|
|
}
|
|
|
|
// If brand new node, make space in type array, and give it a type.
|
|
ensure_type_or_null(n);
|
|
if (type_or_null(n) == NULL) {
|
|
set_type_bottom(n);
|
|
}
|
|
|
|
return transform_old(n);
|
|
}
|
|
|
|
Node *PhaseIterGVN::transform_old(Node* n) {
|
|
DEBUG_ONLY(uint loop_count = 0;);
|
|
NOT_PRODUCT(set_transforms());
|
|
|
|
// Remove 'n' from hash table in case it gets modified
|
|
_table.hash_delete(n);
|
|
if (VerifyIterativeGVN) {
|
|
assert(!_table.find_index(n->_idx), "found duplicate entry in table");
|
|
}
|
|
|
|
// Apply the Ideal call in a loop until it no longer applies
|
|
Node* k = n;
|
|
DEBUG_ONLY(dead_loop_check(k);)
|
|
DEBUG_ONLY(bool is_new = (k->outcnt() == 0);)
|
|
C->remove_modified_node(k);
|
|
Node* i = apply_ideal(k, /*can_reshape=*/true);
|
|
assert(i != k || is_new || i->outcnt() > 0, "don't return dead nodes");
|
|
#ifndef PRODUCT
|
|
verify_step(k);
|
|
#endif
|
|
|
|
while (i != NULL) {
|
|
#ifdef ASSERT
|
|
if (loop_count >= K) {
|
|
dump_infinite_loop_info(i);
|
|
}
|
|
loop_count++;
|
|
#endif
|
|
assert((i->_idx >= k->_idx) || i->is_top(), "Idealize should return new nodes, use Identity to return old nodes");
|
|
// Made a change; put users of original Node on worklist
|
|
add_users_to_worklist(k);
|
|
// Replacing root of transform tree?
|
|
if (k != i) {
|
|
// Make users of old Node now use new.
|
|
subsume_node(k, i);
|
|
k = i;
|
|
}
|
|
DEBUG_ONLY(dead_loop_check(k);)
|
|
// Try idealizing again
|
|
DEBUG_ONLY(is_new = (k->outcnt() == 0);)
|
|
C->remove_modified_node(k);
|
|
i = apply_ideal(k, /*can_reshape=*/true);
|
|
assert(i != k || is_new || (i->outcnt() > 0), "don't return dead nodes");
|
|
#ifndef PRODUCT
|
|
verify_step(k);
|
|
#endif
|
|
}
|
|
|
|
// If brand new node, make space in type array.
|
|
ensure_type_or_null(k);
|
|
|
|
// See what kind of values 'k' takes on at runtime
|
|
const Type* t = k->Value(this);
|
|
assert(t != NULL, "value sanity");
|
|
|
|
// Since I just called 'Value' to compute the set of run-time values
|
|
// for this Node, and 'Value' is non-local (and therefore expensive) I'll
|
|
// cache Value. Later requests for the local phase->type of this Node can
|
|
// use the cached Value instead of suffering with 'bottom_type'.
|
|
if (type_or_null(k) != t) {
|
|
#ifndef PRODUCT
|
|
inc_new_values();
|
|
set_progress();
|
|
#endif
|
|
set_type(k, t);
|
|
// If k is a TypeNode, capture any more-precise type permanently into Node
|
|
k->raise_bottom_type(t);
|
|
// Move users of node to worklist
|
|
add_users_to_worklist(k);
|
|
}
|
|
// If 'k' computes a constant, replace it with a constant
|
|
if (t->singleton() && !k->is_Con()) {
|
|
NOT_PRODUCT(set_progress();)
|
|
Node* con = makecon(t); // Make a constant
|
|
add_users_to_worklist(k);
|
|
subsume_node(k, con); // Everybody using k now uses con
|
|
return con;
|
|
}
|
|
|
|
// Now check for Identities
|
|
i = k->Identity(this); // Look for a nearby replacement
|
|
if (i != k) { // Found? Return replacement!
|
|
NOT_PRODUCT(set_progress();)
|
|
add_users_to_worklist(k);
|
|
subsume_node(k, i); // Everybody using k now uses i
|
|
return i;
|
|
}
|
|
|
|
// Global Value Numbering
|
|
i = hash_find_insert(k); // Check for pre-existing node
|
|
if (i && (i != k)) {
|
|
// Return the pre-existing node if it isn't dead
|
|
NOT_PRODUCT(set_progress();)
|
|
add_users_to_worklist(k);
|
|
subsume_node(k, i); // Everybody using k now uses i
|
|
return i;
|
|
}
|
|
|
|
// Return Idealized original
|
|
return k;
|
|
}
|
|
|
|
//---------------------------------saturate------------------------------------
|
|
const Type* PhaseIterGVN::saturate(const Type* new_type, const Type* old_type,
|
|
const Type* limit_type) const {
|
|
return new_type->narrow(old_type);
|
|
}
|
|
|
|
//------------------------------remove_globally_dead_node----------------------
|
|
// Kill a globally dead Node. All uses are also globally dead and are
|
|
// aggressively trimmed.
|
|
void PhaseIterGVN::remove_globally_dead_node( Node *dead ) {
|
|
enum DeleteProgress {
|
|
PROCESS_INPUTS,
|
|
PROCESS_OUTPUTS
|
|
};
|
|
assert(_stack.is_empty(), "not empty");
|
|
_stack.push(dead, PROCESS_INPUTS);
|
|
|
|
while (_stack.is_nonempty()) {
|
|
dead = _stack.node();
|
|
if (dead->Opcode() == Op_SafePoint) {
|
|
dead->as_SafePoint()->disconnect_from_root(this);
|
|
}
|
|
uint progress_state = _stack.index();
|
|
assert(dead != C->root(), "killing root, eh?");
|
|
assert(!dead->is_top(), "add check for top when pushing");
|
|
NOT_PRODUCT( set_progress(); )
|
|
if (progress_state == PROCESS_INPUTS) {
|
|
// After following inputs, continue to outputs
|
|
_stack.set_index(PROCESS_OUTPUTS);
|
|
if (!dead->is_Con()) { // Don't kill cons but uses
|
|
bool recurse = false;
|
|
// Remove from hash table
|
|
_table.hash_delete( dead );
|
|
// Smash all inputs to 'dead', isolating him completely
|
|
for (uint i = 0; i < dead->req(); i++) {
|
|
Node *in = dead->in(i);
|
|
if (in != NULL && in != C->top()) { // Points to something?
|
|
int nrep = dead->replace_edge(in, NULL); // Kill edges
|
|
assert((nrep > 0), "sanity");
|
|
if (in->outcnt() == 0) { // Made input go dead?
|
|
_stack.push(in, PROCESS_INPUTS); // Recursively remove
|
|
recurse = true;
|
|
} else if (in->outcnt() == 1 &&
|
|
in->has_special_unique_user()) {
|
|
_worklist.push(in->unique_out());
|
|
} else if (in->outcnt() <= 2 && dead->is_Phi()) {
|
|
if (in->Opcode() == Op_Region) {
|
|
_worklist.push(in);
|
|
} else if (in->is_Store()) {
|
|
DUIterator_Fast imax, i = in->fast_outs(imax);
|
|
_worklist.push(in->fast_out(i));
|
|
i++;
|
|
if (in->outcnt() == 2) {
|
|
_worklist.push(in->fast_out(i));
|
|
i++;
|
|
}
|
|
assert(!(i < imax), "sanity");
|
|
}
|
|
} else {
|
|
BarrierSet::barrier_set()->barrier_set_c2()->enqueue_useful_gc_barrier(this, in);
|
|
}
|
|
if (ReduceFieldZeroing && dead->is_Load() && i == MemNode::Memory &&
|
|
in->is_Proj() && in->in(0) != NULL && in->in(0)->is_Initialize()) {
|
|
// A Load that directly follows an InitializeNode is
|
|
// going away. The Stores that follow are candidates
|
|
// again to be captured by the InitializeNode.
|
|
for (DUIterator_Fast jmax, j = in->fast_outs(jmax); j < jmax; j++) {
|
|
Node *n = in->fast_out(j);
|
|
if (n->is_Store()) {
|
|
_worklist.push(n);
|
|
}
|
|
}
|
|
}
|
|
} // if (in != NULL && in != C->top())
|
|
} // for (uint i = 0; i < dead->req(); i++)
|
|
if (recurse) {
|
|
continue;
|
|
}
|
|
} // if (!dead->is_Con())
|
|
} // if (progress_state == PROCESS_INPUTS)
|
|
|
|
// Aggressively kill globally dead uses
|
|
// (Rather than pushing all the outs at once, we push one at a time,
|
|
// plus the parent to resume later, because of the indefinite number
|
|
// of edge deletions per loop trip.)
|
|
if (dead->outcnt() > 0) {
|
|
// Recursively remove output edges
|
|
_stack.push(dead->raw_out(0), PROCESS_INPUTS);
|
|
} else {
|
|
// Finished disconnecting all input and output edges.
|
|
_stack.pop();
|
|
// Remove dead node from iterative worklist
|
|
_worklist.remove(dead);
|
|
C->remove_modified_node(dead);
|
|
// Constant node that has no out-edges and has only one in-edge from
|
|
// root is usually dead. However, sometimes reshaping walk makes
|
|
// it reachable by adding use edges. So, we will NOT count Con nodes
|
|
// as dead to be conservative about the dead node count at any
|
|
// given time.
|
|
if (!dead->is_Con()) {
|
|
C->record_dead_node(dead->_idx);
|
|
}
|
|
if (dead->is_macro()) {
|
|
C->remove_macro_node(dead);
|
|
}
|
|
if (dead->is_expensive()) {
|
|
C->remove_expensive_node(dead);
|
|
}
|
|
if (dead->for_post_loop_opts_igvn()) {
|
|
C->remove_from_post_loop_opts_igvn(dead);
|
|
}
|
|
BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
|
|
bs->unregister_potential_barrier_node(dead);
|
|
}
|
|
} // while (_stack.is_nonempty())
|
|
}
|
|
|
|
//------------------------------subsume_node-----------------------------------
|
|
// Remove users from node 'old' and add them to node 'nn'.
|
|
void PhaseIterGVN::subsume_node( Node *old, Node *nn ) {
|
|
if (old->Opcode() == Op_SafePoint) {
|
|
old->as_SafePoint()->disconnect_from_root(this);
|
|
}
|
|
assert( old != hash_find(old), "should already been removed" );
|
|
assert( old != C->top(), "cannot subsume top node");
|
|
// Copy debug or profile information to the new version:
|
|
C->copy_node_notes_to(nn, old);
|
|
// Move users of node 'old' to node 'nn'
|
|
for (DUIterator_Last imin, i = old->last_outs(imin); i >= imin; ) {
|
|
Node* use = old->last_out(i); // for each use...
|
|
// use might need re-hashing (but it won't if it's a new node)
|
|
rehash_node_delayed(use);
|
|
// Update use-def info as well
|
|
// We remove all occurrences of old within use->in,
|
|
// so as to avoid rehashing any node more than once.
|
|
// The hash table probe swamps any outer loop overhead.
|
|
uint num_edges = 0;
|
|
for (uint jmax = use->len(), j = 0; j < jmax; j++) {
|
|
if (use->in(j) == old) {
|
|
use->set_req(j, nn);
|
|
++num_edges;
|
|
}
|
|
}
|
|
i -= num_edges; // we deleted 1 or more copies of this edge
|
|
}
|
|
|
|
// Search for instance field data PhiNodes in the same region pointing to the old
|
|
// memory PhiNode and update their instance memory ids to point to the new node.
|
|
if (old->is_Phi() && old->as_Phi()->type()->has_memory() && old->in(0) != NULL) {
|
|
Node* region = old->in(0);
|
|
for (DUIterator_Fast imax, i = region->fast_outs(imax); i < imax; i++) {
|
|
PhiNode* phi = region->fast_out(i)->isa_Phi();
|
|
if (phi != NULL && phi->inst_mem_id() == (int)old->_idx) {
|
|
phi->set_inst_mem_id((int)nn->_idx);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Smash all inputs to 'old', isolating him completely
|
|
Node *temp = new Node(1);
|
|
temp->init_req(0,nn); // Add a use to nn to prevent him from dying
|
|
remove_dead_node( old );
|
|
temp->del_req(0); // Yank bogus edge
|
|
#ifndef PRODUCT
|
|
if( VerifyIterativeGVN ) {
|
|
for ( int i = 0; i < _verify_window_size; i++ ) {
|
|
if ( _verify_window[i] == old )
|
|
_verify_window[i] = nn;
|
|
}
|
|
}
|
|
#endif
|
|
temp->destruct(this); // reuse the _idx of this little guy
|
|
}
|
|
|
|
//------------------------------add_users_to_worklist--------------------------
|
|
void PhaseIterGVN::add_users_to_worklist0( Node *n ) {
|
|
for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
|
|
_worklist.push(n->fast_out(i)); // Push on worklist
|
|
}
|
|
}
|
|
|
|
// Return counted loop Phi if as a counted loop exit condition, cmp
|
|
// compares the the induction variable with n
|
|
static PhiNode* countedloop_phi_from_cmp(CmpINode* cmp, Node* n) {
|
|
for (DUIterator_Fast imax, i = cmp->fast_outs(imax); i < imax; i++) {
|
|
Node* bol = cmp->fast_out(i);
|
|
for (DUIterator_Fast i2max, i2 = bol->fast_outs(i2max); i2 < i2max; i2++) {
|
|
Node* iff = bol->fast_out(i2);
|
|
if (iff->is_CountedLoopEnd()) {
|
|
CountedLoopEndNode* cle = iff->as_CountedLoopEnd();
|
|
if (cle->limit() == n) {
|
|
PhiNode* phi = cle->phi();
|
|
if (phi != NULL) {
|
|
return phi;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
void PhaseIterGVN::add_users_to_worklist( Node *n ) {
|
|
add_users_to_worklist0(n);
|
|
|
|
// Move users of node to worklist
|
|
for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
|
|
Node* use = n->fast_out(i); // Get use
|
|
|
|
if( use->is_Multi() || // Multi-definer? Push projs on worklist
|
|
use->is_Store() ) // Enable store/load same address
|
|
add_users_to_worklist0(use);
|
|
|
|
// If we changed the receiver type to a call, we need to revisit
|
|
// the Catch following the call. It's looking for a non-NULL
|
|
// receiver to know when to enable the regular fall-through path
|
|
// in addition to the NullPtrException path.
|
|
if (use->is_CallDynamicJava() && n == use->in(TypeFunc::Parms)) {
|
|
Node* p = use->as_CallDynamicJava()->proj_out_or_null(TypeFunc::Control);
|
|
if (p != NULL) {
|
|
add_users_to_worklist0(p);
|
|
}
|
|
}
|
|
|
|
uint use_op = use->Opcode();
|
|
if(use->is_Cmp()) { // Enable CMP/BOOL optimization
|
|
add_users_to_worklist(use); // Put Bool on worklist
|
|
if (use->outcnt() > 0) {
|
|
Node* bol = use->raw_out(0);
|
|
if (bol->outcnt() > 0) {
|
|
Node* iff = bol->raw_out(0);
|
|
if (iff->outcnt() == 2) {
|
|
// Look for the 'is_x2logic' pattern: "x ? : 0 : 1" and put the
|
|
// phi merging either 0 or 1 onto the worklist
|
|
Node* ifproj0 = iff->raw_out(0);
|
|
Node* ifproj1 = iff->raw_out(1);
|
|
if (ifproj0->outcnt() > 0 && ifproj1->outcnt() > 0) {
|
|
Node* region0 = ifproj0->raw_out(0);
|
|
Node* region1 = ifproj1->raw_out(0);
|
|
if( region0 == region1 )
|
|
add_users_to_worklist0(region0);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (use_op == Op_CmpI) {
|
|
Node* phi = countedloop_phi_from_cmp((CmpINode*)use, n);
|
|
if (phi != NULL) {
|
|
// If an opaque node feeds into the limit condition of a
|
|
// CountedLoop, we need to process the Phi node for the
|
|
// induction variable when the opaque node is removed:
|
|
// the range of values taken by the Phi is now known and
|
|
// so its type is also known.
|
|
_worklist.push(phi);
|
|
}
|
|
Node* in1 = use->in(1);
|
|
for (uint i = 0; i < in1->outcnt(); i++) {
|
|
if (in1->raw_out(i)->Opcode() == Op_CastII) {
|
|
Node* castii = in1->raw_out(i);
|
|
if (castii->in(0) != NULL && castii->in(0)->in(0) != NULL && castii->in(0)->in(0)->is_If()) {
|
|
Node* ifnode = castii->in(0)->in(0);
|
|
if (ifnode->in(1) != NULL && ifnode->in(1)->is_Bool() && ifnode->in(1)->in(1) == use) {
|
|
// Reprocess a CastII node that may depend on an
|
|
// opaque node value when the opaque node is
|
|
// removed. In case it carries a dependency we can do
|
|
// a better job of computing its type.
|
|
_worklist.push(castii);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// If changed Cast input, check Phi users for simple cycles
|
|
if (use->is_ConstraintCast()) {
|
|
for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
|
|
Node* u = use->fast_out(i2);
|
|
if (u->is_Phi())
|
|
_worklist.push(u);
|
|
}
|
|
}
|
|
// If changed LShift inputs, check RShift users for useless sign-ext
|
|
if( use_op == Op_LShiftI ) {
|
|
for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
|
|
Node* u = use->fast_out(i2);
|
|
if (u->Opcode() == Op_RShiftI)
|
|
_worklist.push(u);
|
|
}
|
|
}
|
|
// If changed AddI/SubI inputs, check CmpU for range check optimization.
|
|
if (use_op == Op_AddI || use_op == Op_SubI) {
|
|
for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
|
|
Node* u = use->fast_out(i2);
|
|
if (u->is_Cmp() && (u->Opcode() == Op_CmpU)) {
|
|
_worklist.push(u);
|
|
}
|
|
}
|
|
}
|
|
// If changed AddP inputs, check Stores for loop invariant
|
|
if( use_op == Op_AddP ) {
|
|
for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
|
|
Node* u = use->fast_out(i2);
|
|
if (u->is_Mem())
|
|
_worklist.push(u);
|
|
}
|
|
}
|
|
// If changed initialization activity, check dependent Stores
|
|
if (use_op == Op_Allocate || use_op == Op_AllocateArray) {
|
|
InitializeNode* init = use->as_Allocate()->initialization();
|
|
if (init != NULL) {
|
|
Node* imem = init->proj_out_or_null(TypeFunc::Memory);
|
|
if (imem != NULL) add_users_to_worklist0(imem);
|
|
}
|
|
}
|
|
if (use_op == Op_Initialize) {
|
|
Node* imem = use->as_Initialize()->proj_out_or_null(TypeFunc::Memory);
|
|
if (imem != NULL) add_users_to_worklist0(imem);
|
|
}
|
|
// Loading the java mirror from a Klass requires two loads and the type
|
|
// of the mirror load depends on the type of 'n'. See LoadNode::Value().
|
|
// LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror))))
|
|
BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
|
|
bool has_load_barrier_nodes = bs->has_load_barrier_nodes();
|
|
|
|
if (use_op == Op_LoadP && use->bottom_type()->isa_rawptr()) {
|
|
for (DUIterator_Fast i2max, i2 = use->fast_outs(i2max); i2 < i2max; i2++) {
|
|
Node* u = use->fast_out(i2);
|
|
const Type* ut = u->bottom_type();
|
|
if (u->Opcode() == Op_LoadP && ut->isa_instptr()) {
|
|
if (has_load_barrier_nodes) {
|
|
// Search for load barriers behind the load
|
|
for (DUIterator_Fast i3max, i3 = u->fast_outs(i3max); i3 < i3max; i3++) {
|
|
Node* b = u->fast_out(i3);
|
|
if (bs->is_gc_barrier_node(b)) {
|
|
_worklist.push(b);
|
|
}
|
|
}
|
|
}
|
|
_worklist.push(u);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Remove the speculative part of all types that we know of
|
|
*/
|
|
void PhaseIterGVN::remove_speculative_types() {
|
|
assert(UseTypeSpeculation, "speculation is off");
|
|
for (uint i = 0; i < _types.Size(); i++) {
|
|
const Type* t = _types.fast_lookup(i);
|
|
if (t != NULL) {
|
|
_types.map(i, t->remove_speculative());
|
|
}
|
|
}
|
|
_table.check_no_speculative_types();
|
|
}
|
|
|
|
//=============================================================================
|
|
#ifndef PRODUCT
|
|
uint PhaseCCP::_total_invokes = 0;
|
|
uint PhaseCCP::_total_constants = 0;
|
|
#endif
|
|
//------------------------------PhaseCCP---------------------------------------
|
|
// Conditional Constant Propagation, ala Wegman & Zadeck
|
|
PhaseCCP::PhaseCCP( PhaseIterGVN *igvn ) : PhaseIterGVN(igvn) {
|
|
NOT_PRODUCT( clear_constants(); )
|
|
assert( _worklist.size() == 0, "" );
|
|
// Clear out _nodes from IterGVN. Must be clear to transform call.
|
|
_nodes.clear(); // Clear out from IterGVN
|
|
analyze();
|
|
}
|
|
|
|
#ifndef PRODUCT
|
|
//------------------------------~PhaseCCP--------------------------------------
|
|
PhaseCCP::~PhaseCCP() {
|
|
inc_invokes();
|
|
_total_constants += count_constants();
|
|
}
|
|
#endif
|
|
|
|
|
|
#ifdef ASSERT
|
|
static bool ccp_type_widens(const Type* t, const Type* t0) {
|
|
assert(t->meet(t0) == t, "Not monotonic");
|
|
switch (t->base() == t0->base() ? t->base() : Type::Top) {
|
|
case Type::Int:
|
|
assert(t0->isa_int()->_widen <= t->isa_int()->_widen, "widen increases");
|
|
break;
|
|
case Type::Long:
|
|
assert(t0->isa_long()->_widen <= t->isa_long()->_widen, "widen increases");
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
return true;
|
|
}
|
|
#endif //ASSERT
|
|
|
|
//------------------------------analyze----------------------------------------
|
|
void PhaseCCP::analyze() {
|
|
// Initialize all types to TOP, optimistic analysis
|
|
for (int i = C->unique() - 1; i >= 0; i--) {
|
|
_types.map(i,Type::TOP);
|
|
}
|
|
|
|
// Push root onto worklist
|
|
Unique_Node_List worklist;
|
|
worklist.push(C->root());
|
|
|
|
// Pull from worklist; compute new value; push changes out.
|
|
// This loop is the meat of CCP.
|
|
while( worklist.size() ) {
|
|
Node *n = worklist.pop();
|
|
const Type *t = n->Value(this);
|
|
if (t != type(n)) {
|
|
assert(ccp_type_widens(t, type(n)), "ccp type must widen");
|
|
#ifndef PRODUCT
|
|
if( TracePhaseCCP ) {
|
|
t->dump();
|
|
do { tty->print("\t"); } while (tty->position() < 16);
|
|
n->dump();
|
|
}
|
|
#endif
|
|
set_type(n, t);
|
|
for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
|
|
Node* m = n->fast_out(i); // Get user
|
|
if (m->is_Region()) { // New path to Region? Must recheck Phis too
|
|
for (DUIterator_Fast i2max, i2 = m->fast_outs(i2max); i2 < i2max; i2++) {
|
|
Node* p = m->fast_out(i2); // Propagate changes to uses
|
|
if (p->bottom_type() != type(p)) { // If not already bottomed out
|
|
worklist.push(p); // Propagate change to user
|
|
}
|
|
}
|
|
}
|
|
// If we changed the receiver type to a call, we need to revisit
|
|
// the Catch following the call. It's looking for a non-NULL
|
|
// receiver to know when to enable the regular fall-through path
|
|
// in addition to the NullPtrException path
|
|
if (m->is_Call()) {
|
|
for (DUIterator_Fast i2max, i2 = m->fast_outs(i2max); i2 < i2max; i2++) {
|
|
Node* p = m->fast_out(i2); // Propagate changes to uses
|
|
if (p->is_Proj() && p->as_Proj()->_con == TypeFunc::Control) {
|
|
Node* catch_node = p->find_out_with(Op_Catch);
|
|
if (catch_node != NULL) {
|
|
worklist.push(catch_node);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (m->bottom_type() != type(m)) { // If not already bottomed out
|
|
worklist.push(m); // Propagate change to user
|
|
}
|
|
|
|
// CmpU nodes can get their type information from two nodes up in the
|
|
// graph (instead of from the nodes immediately above). Make sure they
|
|
// are added to the worklist if nodes they depend on are updated, since
|
|
// they could be missed and get wrong types otherwise.
|
|
uint m_op = m->Opcode();
|
|
if (m_op == Op_AddI || m_op == Op_SubI) {
|
|
for (DUIterator_Fast i2max, i2 = m->fast_outs(i2max); i2 < i2max; i2++) {
|
|
Node* p = m->fast_out(i2); // Propagate changes to uses
|
|
if (p->Opcode() == Op_CmpU) {
|
|
// Got a CmpU which might need the new type information from node n.
|
|
if(p->bottom_type() != type(p)) { // If not already bottomed out
|
|
worklist.push(p); // Propagate change to user
|
|
}
|
|
}
|
|
}
|
|
}
|
|
// If n is used in a counted loop exit condition then the type
|
|
// of the counted loop's Phi depends on the type of n. See
|
|
// PhiNode::Value().
|
|
if (m_op == Op_CmpI) {
|
|
PhiNode* phi = countedloop_phi_from_cmp((CmpINode*)m, n);
|
|
if (phi != NULL) {
|
|
worklist.push(phi);
|
|
}
|
|
}
|
|
// Loading the java mirror from a Klass requires two loads and the type
|
|
// of the mirror load depends on the type of 'n'. See LoadNode::Value().
|
|
BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
|
|
bool has_load_barrier_nodes = bs->has_load_barrier_nodes();
|
|
|
|
if (m_op == Op_LoadP && m->bottom_type()->isa_rawptr()) {
|
|
for (DUIterator_Fast i2max, i2 = m->fast_outs(i2max); i2 < i2max; i2++) {
|
|
Node* u = m->fast_out(i2);
|
|
const Type* ut = u->bottom_type();
|
|
if (u->Opcode() == Op_LoadP && ut->isa_instptr() && ut != type(u)) {
|
|
if (has_load_barrier_nodes) {
|
|
// Search for load barriers behind the load
|
|
for (DUIterator_Fast i3max, i3 = u->fast_outs(i3max); i3 < i3max; i3++) {
|
|
Node* b = u->fast_out(i3);
|
|
if (bs->is_gc_barrier_node(b)) {
|
|
worklist.push(b);
|
|
}
|
|
}
|
|
}
|
|
worklist.push(u);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
//------------------------------do_transform-----------------------------------
|
|
// Top level driver for the recursive transformer
|
|
void PhaseCCP::do_transform() {
|
|
// Correct leaves of new-space Nodes; they point to old-space.
|
|
C->set_root( transform(C->root())->as_Root() );
|
|
assert( C->top(), "missing TOP node" );
|
|
assert( C->root(), "missing root" );
|
|
}
|
|
|
|
//------------------------------transform--------------------------------------
|
|
// Given a Node in old-space, clone him into new-space.
|
|
// Convert any of his old-space children into new-space children.
|
|
Node *PhaseCCP::transform( Node *n ) {
|
|
Node *new_node = _nodes[n->_idx]; // Check for transformed node
|
|
if( new_node != NULL )
|
|
return new_node; // Been there, done that, return old answer
|
|
new_node = transform_once(n); // Check for constant
|
|
_nodes.map( n->_idx, new_node ); // Flag as having been cloned
|
|
|
|
// Allocate stack of size _nodes.Size()/2 to avoid frequent realloc
|
|
GrowableArray <Node *> trstack(C->live_nodes() >> 1);
|
|
|
|
trstack.push(new_node); // Process children of cloned node
|
|
while ( trstack.is_nonempty() ) {
|
|
Node *clone = trstack.pop();
|
|
uint cnt = clone->req();
|
|
for( uint i = 0; i < cnt; i++ ) { // For all inputs do
|
|
Node *input = clone->in(i);
|
|
if( input != NULL ) { // Ignore NULLs
|
|
Node *new_input = _nodes[input->_idx]; // Check for cloned input node
|
|
if( new_input == NULL ) {
|
|
new_input = transform_once(input); // Check for constant
|
|
_nodes.map( input->_idx, new_input );// Flag as having been cloned
|
|
trstack.push(new_input);
|
|
}
|
|
assert( new_input == clone->in(i), "insanity check");
|
|
}
|
|
}
|
|
}
|
|
return new_node;
|
|
}
|
|
|
|
|
|
//------------------------------transform_once---------------------------------
|
|
// For PhaseCCP, transformation is IDENTITY unless Node computed a constant.
|
|
Node *PhaseCCP::transform_once( Node *n ) {
|
|
const Type *t = type(n);
|
|
// Constant? Use constant Node instead
|
|
if( t->singleton() ) {
|
|
Node *nn = n; // Default is to return the original constant
|
|
if( t == Type::TOP ) {
|
|
// cache my top node on the Compile instance
|
|
if( C->cached_top_node() == NULL || C->cached_top_node()->in(0) == NULL ) {
|
|
C->set_cached_top_node(ConNode::make(Type::TOP));
|
|
set_type(C->top(), Type::TOP);
|
|
}
|
|
nn = C->top();
|
|
}
|
|
if( !n->is_Con() ) {
|
|
if( t != Type::TOP ) {
|
|
nn = makecon(t); // ConNode::make(t);
|
|
NOT_PRODUCT( inc_constants(); )
|
|
} else if( n->is_Region() ) { // Unreachable region
|
|
// Note: nn == C->top()
|
|
n->set_req(0, NULL); // Cut selfreference
|
|
bool progress = true;
|
|
uint max = n->outcnt();
|
|
DUIterator i;
|
|
while (progress) {
|
|
progress = false;
|
|
// Eagerly remove dead phis to avoid phis copies creation.
|
|
for (i = n->outs(); n->has_out(i); i++) {
|
|
Node* m = n->out(i);
|
|
if (m->is_Phi()) {
|
|
assert(type(m) == Type::TOP, "Unreachable region should not have live phis.");
|
|
replace_node(m, nn);
|
|
if (max != n->outcnt()) {
|
|
progress = true;
|
|
i = n->refresh_out_pos(i);
|
|
max = n->outcnt();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
replace_node(n,nn); // Update DefUse edges for new constant
|
|
}
|
|
return nn;
|
|
}
|
|
|
|
// If x is a TypeNode, capture any more-precise type permanently into Node
|
|
if (t != n->bottom_type()) {
|
|
hash_delete(n); // changing bottom type may force a rehash
|
|
n->raise_bottom_type(t);
|
|
_worklist.push(n); // n re-enters the hash table via the worklist
|
|
}
|
|
|
|
// TEMPORARY fix to ensure that 2nd GVN pass eliminates NULL checks
|
|
switch( n->Opcode() ) {
|
|
case Op_FastLock: // Revisit FastLocks for lock coarsening
|
|
case Op_If:
|
|
case Op_CountedLoopEnd:
|
|
case Op_Region:
|
|
case Op_Loop:
|
|
case Op_CountedLoop:
|
|
case Op_Conv2B:
|
|
case Op_Opaque1:
|
|
case Op_Opaque2:
|
|
_worklist.push(n);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return n;
|
|
}
|
|
|
|
//---------------------------------saturate------------------------------------
|
|
const Type* PhaseCCP::saturate(const Type* new_type, const Type* old_type,
|
|
const Type* limit_type) const {
|
|
const Type* wide_type = new_type->widen(old_type, limit_type);
|
|
if (wide_type != new_type) { // did we widen?
|
|
// If so, we may have widened beyond the limit type. Clip it back down.
|
|
new_type = wide_type->filter(limit_type);
|
|
}
|
|
return new_type;
|
|
}
|
|
|
|
//------------------------------print_statistics-------------------------------
|
|
#ifndef PRODUCT
|
|
void PhaseCCP::print_statistics() {
|
|
tty->print_cr("CCP: %d constants found: %d", _total_invokes, _total_constants);
|
|
}
|
|
#endif
|
|
|
|
|
|
//=============================================================================
|
|
#ifndef PRODUCT
|
|
uint PhasePeephole::_total_peepholes = 0;
|
|
#endif
|
|
//------------------------------PhasePeephole----------------------------------
|
|
// Conditional Constant Propagation, ala Wegman & Zadeck
|
|
PhasePeephole::PhasePeephole( PhaseRegAlloc *regalloc, PhaseCFG &cfg )
|
|
: PhaseTransform(Peephole), _regalloc(regalloc), _cfg(cfg) {
|
|
NOT_PRODUCT( clear_peepholes(); )
|
|
}
|
|
|
|
#ifndef PRODUCT
|
|
//------------------------------~PhasePeephole---------------------------------
|
|
PhasePeephole::~PhasePeephole() {
|
|
_total_peepholes += count_peepholes();
|
|
}
|
|
#endif
|
|
|
|
//------------------------------transform--------------------------------------
|
|
Node *PhasePeephole::transform( Node *n ) {
|
|
ShouldNotCallThis();
|
|
return NULL;
|
|
}
|
|
|
|
//------------------------------do_transform-----------------------------------
|
|
void PhasePeephole::do_transform() {
|
|
bool method_name_not_printed = true;
|
|
|
|
// Examine each basic block
|
|
for (uint block_number = 1; block_number < _cfg.number_of_blocks(); ++block_number) {
|
|
Block* block = _cfg.get_block(block_number);
|
|
bool block_not_printed = true;
|
|
|
|
// and each instruction within a block
|
|
uint end_index = block->number_of_nodes();
|
|
// block->end_idx() not valid after PhaseRegAlloc
|
|
for( uint instruction_index = 1; instruction_index < end_index; ++instruction_index ) {
|
|
Node *n = block->get_node(instruction_index);
|
|
if( n->is_Mach() ) {
|
|
MachNode *m = n->as_Mach();
|
|
int deleted_count = 0;
|
|
// check for peephole opportunities
|
|
MachNode *m2 = m->peephole(block, instruction_index, _regalloc, deleted_count);
|
|
if( m2 != NULL ) {
|
|
#ifndef PRODUCT
|
|
if( PrintOptoPeephole ) {
|
|
// Print method, first time only
|
|
if( C->method() && method_name_not_printed ) {
|
|
C->method()->print_short_name(); tty->cr();
|
|
method_name_not_printed = false;
|
|
}
|
|
// Print this block
|
|
if( Verbose && block_not_printed) {
|
|
tty->print_cr("in block");
|
|
block->dump();
|
|
block_not_printed = false;
|
|
}
|
|
// Print instructions being deleted
|
|
for( int i = (deleted_count - 1); i >= 0; --i ) {
|
|
block->get_node(instruction_index-i)->as_Mach()->format(_regalloc); tty->cr();
|
|
}
|
|
tty->print_cr("replaced with");
|
|
// Print new instruction
|
|
m2->format(_regalloc);
|
|
tty->print("\n\n");
|
|
}
|
|
#endif
|
|
// Remove old nodes from basic block and update instruction_index
|
|
// (old nodes still exist and may have edges pointing to them
|
|
// as register allocation info is stored in the allocator using
|
|
// the node index to live range mappings.)
|
|
uint safe_instruction_index = (instruction_index - deleted_count);
|
|
for( ; (instruction_index > safe_instruction_index); --instruction_index ) {
|
|
block->remove_node( instruction_index );
|
|
}
|
|
// install new node after safe_instruction_index
|
|
block->insert_node(m2, safe_instruction_index + 1);
|
|
end_index = block->number_of_nodes() - 1; // Recompute new block size
|
|
NOT_PRODUCT( inc_peepholes(); )
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
//------------------------------print_statistics-------------------------------
|
|
#ifndef PRODUCT
|
|
void PhasePeephole::print_statistics() {
|
|
tty->print_cr("Peephole: peephole rules applied: %d", _total_peepholes);
|
|
}
|
|
#endif
|
|
|
|
|
|
//=============================================================================
|
|
//------------------------------set_req_X--------------------------------------
|
|
void Node::set_req_X( uint i, Node *n, PhaseIterGVN *igvn ) {
|
|
assert( is_not_dead(n), "can not use dead node");
|
|
assert( igvn->hash_find(this) != this, "Need to remove from hash before changing edges" );
|
|
Node *old = in(i);
|
|
set_req(i, n);
|
|
|
|
// old goes dead?
|
|
if( old ) {
|
|
switch (old->outcnt()) {
|
|
case 0:
|
|
// Put into the worklist to kill later. We do not kill it now because the
|
|
// recursive kill will delete the current node (this) if dead-loop exists
|
|
if (!old->is_top())
|
|
igvn->_worklist.push( old );
|
|
break;
|
|
case 1:
|
|
if( old->is_Store() || old->has_special_unique_user() )
|
|
igvn->add_users_to_worklist( old );
|
|
break;
|
|
case 2:
|
|
if( old->is_Store() )
|
|
igvn->add_users_to_worklist( old );
|
|
if( old->Opcode() == Op_Region )
|
|
igvn->_worklist.push(old);
|
|
break;
|
|
case 3:
|
|
if( old->Opcode() == Op_Region ) {
|
|
igvn->_worklist.push(old);
|
|
igvn->add_users_to_worklist( old );
|
|
}
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
BarrierSet::barrier_set()->barrier_set_c2()->enqueue_useful_gc_barrier(igvn, old);
|
|
}
|
|
|
|
}
|
|
|
|
//-------------------------------replace_by-----------------------------------
|
|
// Using def-use info, replace one node for another. Follow the def-use info
|
|
// to all users of the OLD node. Then make all uses point to the NEW node.
|
|
void Node::replace_by(Node *new_node) {
|
|
assert(!is_top(), "top node has no DU info");
|
|
for (DUIterator_Last imin, i = last_outs(imin); i >= imin; ) {
|
|
Node* use = last_out(i);
|
|
uint uses_found = 0;
|
|
for (uint j = 0; j < use->len(); j++) {
|
|
if (use->in(j) == this) {
|
|
if (j < use->req())
|
|
use->set_req(j, new_node);
|
|
else use->set_prec(j, new_node);
|
|
uses_found++;
|
|
}
|
|
}
|
|
i -= uses_found; // we deleted 1 or more copies of this edge
|
|
}
|
|
}
|
|
|
|
//=============================================================================
|
|
//-----------------------------------------------------------------------------
|
|
void Type_Array::grow( uint i ) {
|
|
if( !_max ) {
|
|
_max = 1;
|
|
_types = (const Type**)_a->Amalloc( _max * sizeof(Type*) );
|
|
_types[0] = NULL;
|
|
}
|
|
uint old = _max;
|
|
_max = next_power_of_2(i);
|
|
_types = (const Type**)_a->Arealloc( _types, old*sizeof(Type*),_max*sizeof(Type*));
|
|
memset( &_types[old], 0, (_max-old)*sizeof(Type*) );
|
|
}
|
|
|
|
//------------------------------dump-------------------------------------------
|
|
#ifndef PRODUCT
|
|
void Type_Array::dump() const {
|
|
uint max = Size();
|
|
for( uint i = 0; i < max; i++ ) {
|
|
if( _types[i] != NULL ) {
|
|
tty->print(" %d\t== ", i); _types[i]->dump(); tty->cr();
|
|
}
|
|
}
|
|
}
|
|
#endif
|