| /* |
| * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "memory/allocation.inline.hpp" |
| #include "opto/callnode.hpp" |
| #include "opto/chaitin.hpp" |
| #include "opto/live.hpp" |
| #include "opto/machnode.hpp" |
| |
| |
| // Compute live-in/live-out. We use a totally incremental algorithm. The LIVE |
| // problem is monotonic. The steady-state solution looks like this: pull a |
| // block from the worklist. It has a set of delta's - values which are newly |
| // live-in from the block. Push these to the live-out sets of all predecessor |
| // blocks. At each predecessor, the new live-out values are ANDed with what is |
| // already live-out (extra stuff is added to the live-out sets). Then the |
| // remaining new live-out values are ANDed with what is locally defined. |
| // Leftover bits become the new live-in for the predecessor block, and the pred |
| // block is put on the worklist. |
| // The locally live-in stuff is computed once and added to predecessor |
| // live-out sets. This separate compilation is done in the outer loop below. |
| PhaseLive::PhaseLive( const PhaseCFG &cfg, const LRG_List &names, Arena *arena ) : Phase(LIVE), _cfg(cfg), _names(names), _arena(arena), _live(0) { |
| } |
| |
| void PhaseLive::compute(uint maxlrg) { |
| _maxlrg = maxlrg; |
| _worklist = new (_arena) Block_List(); |
| |
| // Init the sparse live arrays. This data is live on exit from here! |
| // The _live info is the live-out info. |
| _live = (IndexSet*)_arena->Amalloc(sizeof(IndexSet) * _cfg.number_of_blocks()); |
| uint i; |
| for (i = 0; i < _cfg.number_of_blocks(); i++) { |
| _live[i].initialize(_maxlrg); |
| } |
| |
| // Init the sparse arrays for delta-sets. |
| ResourceMark rm; // Nuke temp storage on exit |
| |
| // Does the memory used by _defs and _deltas get reclaimed? Does it matter? TT |
| |
| // Array of values defined locally in blocks |
| _defs = NEW_RESOURCE_ARRAY(IndexSet,_cfg.number_of_blocks()); |
| for (i = 0; i < _cfg.number_of_blocks(); i++) { |
| _defs[i].initialize(_maxlrg); |
| } |
| |
| // Array of delta-set pointers, indexed by block pre_order-1. |
| _deltas = NEW_RESOURCE_ARRAY(IndexSet*,_cfg.number_of_blocks()); |
| memset( _deltas, 0, sizeof(IndexSet*)* _cfg.number_of_blocks()); |
| |
| _free_IndexSet = NULL; |
| |
| // Blocks having done pass-1 |
| VectorSet first_pass(Thread::current()->resource_area()); |
| |
| // Outer loop: must compute local live-in sets and push into predecessors. |
| for (uint j = _cfg.number_of_blocks(); j > 0; j--) { |
| Block* block = _cfg.get_block(j - 1); |
| |
| // Compute the local live-in set. Start with any new live-out bits. |
| IndexSet* use = getset(block); |
| IndexSet* def = &_defs[block->_pre_order-1]; |
| DEBUG_ONLY(IndexSet *def_outside = getfreeset();) |
| uint i; |
| for (i = block->number_of_nodes(); i > 1; i--) { |
| Node* n = block->get_node(i-1); |
| if (n->is_Phi()) { |
| break; |
| } |
| |
| uint r = _names.at(n->_idx); |
| assert(!def_outside->member(r), "Use of external LRG overlaps the same LRG defined in this block"); |
| def->insert( r ); |
| use->remove( r ); |
| uint cnt = n->req(); |
| for (uint k = 1; k < cnt; k++) { |
| Node *nk = n->in(k); |
| uint nkidx = nk->_idx; |
| if (_cfg.get_block_for_node(nk) != block) { |
| uint u = _names.at(nkidx); |
| use->insert(u); |
| DEBUG_ONLY(def_outside->insert(u);) |
| } |
| } |
| } |
| #ifdef ASSERT |
| def_outside->set_next(_free_IndexSet); |
| _free_IndexSet = def_outside; // Drop onto free list |
| #endif |
| // Remove anything defined by Phis and the block start instruction |
| for (uint k = i; k > 0; k--) { |
| uint r = _names.at(block->get_node(k - 1)->_idx); |
| def->insert(r); |
| use->remove(r); |
| } |
| |
| // Push these live-in things to predecessors |
| for (uint l = 1; l < block->num_preds(); l++) { |
| Block* p = _cfg.get_block_for_node(block->pred(l)); |
| add_liveout(p, use, first_pass); |
| |
| // PhiNode uses go in the live-out set of prior blocks. |
| for (uint k = i; k > 0; k--) { |
| add_liveout(p, _names.at(block->get_node(k-1)->in(l)->_idx), first_pass); |
| } |
| } |
| freeset(block); |
| first_pass.set(block->_pre_order); |
| |
| // Inner loop: blocks that picked up new live-out values to be propagated |
| while (_worklist->size()) { |
| Block* block = _worklist->pop(); |
| IndexSet *delta = getset(block); |
| assert( delta->count(), "missing delta set" ); |
| |
| // Add new-live-in to predecessors live-out sets |
| for (uint l = 1; l < block->num_preds(); l++) { |
| Block* predecessor = _cfg.get_block_for_node(block->pred(l)); |
| add_liveout(predecessor, delta, first_pass); |
| } |
| |
| freeset(block); |
| } // End of while-worklist-not-empty |
| |
| } // End of for-all-blocks-outer-loop |
| |
| // We explicitly clear all of the IndexSets which we are about to release. |
| // This allows us to recycle their internal memory into IndexSet's free list. |
| |
| for (i = 0; i < _cfg.number_of_blocks(); i++) { |
| _defs[i].clear(); |
| if (_deltas[i]) { |
| // Is this always true? |
| _deltas[i]->clear(); |
| } |
| } |
| IndexSet *free = _free_IndexSet; |
| while (free != NULL) { |
| IndexSet *temp = free; |
| free = free->next(); |
| temp->clear(); |
| } |
| |
| } |
| |
| #ifndef PRODUCT |
| void PhaseLive::stats(uint iters) const { |
| } |
| #endif |
| |
| // Get an IndexSet for a block. Return existing one, if any. Make a new |
| // empty one if a prior one does not exist. |
| IndexSet *PhaseLive::getset( Block *p ) { |
| IndexSet *delta = _deltas[p->_pre_order-1]; |
| if( !delta ) // Not on worklist? |
| // Get a free set; flag as being on worklist |
| delta = _deltas[p->_pre_order-1] = getfreeset(); |
| return delta; // Return set of new live-out items |
| } |
| |
| // Pull from free list, or allocate. Internal allocation on the returned set |
| // is always from thread local storage. |
| IndexSet *PhaseLive::getfreeset( ) { |
| IndexSet *f = _free_IndexSet; |
| if( !f ) { |
| f = new IndexSet; |
| // f->set_arena(Thread::current()->resource_area()); |
| f->initialize(_maxlrg, Thread::current()->resource_area()); |
| } else { |
| // Pull from free list |
| _free_IndexSet = f->next(); |
| //f->_cnt = 0; // Reset to empty |
| // f->set_arena(Thread::current()->resource_area()); |
| f->initialize(_maxlrg, Thread::current()->resource_area()); |
| } |
| return f; |
| } |
| |
| // Free an IndexSet from a block. |
| void PhaseLive::freeset( const Block *p ) { |
| IndexSet *f = _deltas[p->_pre_order-1]; |
| f->set_next(_free_IndexSet); |
| _free_IndexSet = f; // Drop onto free list |
| _deltas[p->_pre_order-1] = NULL; |
| } |
| |
| // Add a live-out value to a given blocks live-out set. If it is new, then |
| // also add it to the delta set and stick the block on the worklist. |
| void PhaseLive::add_liveout( Block *p, uint r, VectorSet &first_pass ) { |
| IndexSet *live = &_live[p->_pre_order-1]; |
| if( live->insert(r) ) { // If actually inserted... |
| // We extended the live-out set. See if the value is generated locally. |
| // If it is not, then we must extend the live-in set. |
| if( !_defs[p->_pre_order-1].member( r ) ) { |
| if( !_deltas[p->_pre_order-1] && // Not on worklist? |
| first_pass.test(p->_pre_order) ) |
| _worklist->push(p); // Actually go on worklist if already 1st pass |
| getset(p)->insert(r); |
| } |
| } |
| } |
| |
| // Add a vector of live-out values to a given blocks live-out set. |
| void PhaseLive::add_liveout( Block *p, IndexSet *lo, VectorSet &first_pass ) { |
| IndexSet *live = &_live[p->_pre_order-1]; |
| IndexSet *defs = &_defs[p->_pre_order-1]; |
| IndexSet *on_worklist = _deltas[p->_pre_order-1]; |
| IndexSet *delta = on_worklist ? on_worklist : getfreeset(); |
| |
| IndexSetIterator elements(lo); |
| uint r; |
| while ((r = elements.next()) != 0) { |
| if( live->insert(r) && // If actually inserted... |
| !defs->member( r ) ) // and not defined locally |
| delta->insert(r); // Then add to live-in set |
| } |
| |
| if( delta->count() ) { // If actually added things |
| _deltas[p->_pre_order-1] = delta; // Flag as on worklist now |
| if( !on_worklist && // Not on worklist? |
| first_pass.test(p->_pre_order) ) |
| _worklist->push(p); // Actually go on worklist if already 1st pass |
| } else { // Nothing there; just free it |
| delta->set_next(_free_IndexSet); |
| _free_IndexSet = delta; // Drop onto free list |
| } |
| } |
| |
| #ifndef PRODUCT |
| // Dump the live-out set for a block |
| void PhaseLive::dump( const Block *b ) const { |
| tty->print("Block %d: ",b->_pre_order); |
| tty->print("LiveOut: "); _live[b->_pre_order-1].dump(); |
| uint cnt = b->number_of_nodes(); |
| for( uint i=0; i<cnt; i++ ) { |
| tty->print("L%d/", _names.at(b->get_node(i)->_idx)); |
| b->get_node(i)->dump(); |
| } |
| tty->print("\n"); |
| } |
| |
| // Verify that base pointers and derived pointers are still sane. |
| void PhaseChaitin::verify_base_ptrs( ResourceArea *a ) const { |
| #ifdef ASSERT |
| Unique_Node_List worklist(a); |
| for (uint i = 0; i < _cfg.number_of_blocks(); i++) { |
| Block* block = _cfg.get_block(i); |
| for (uint j = block->end_idx() + 1; j > 1; j--) { |
| Node* n = block->get_node(j-1); |
| if (n->is_Phi()) { |
| break; |
| } |
| // Found a safepoint? |
| if (n->is_MachSafePoint()) { |
| MachSafePointNode *sfpt = n->as_MachSafePoint(); |
| JVMState* jvms = sfpt->jvms(); |
| if (jvms != NULL) { |
| // Now scan for a live derived pointer |
| if (jvms->oopoff() < sfpt->req()) { |
| // Check each derived/base pair |
| for (uint idx = jvms->oopoff(); idx < sfpt->req(); idx++) { |
| Node *check = sfpt->in(idx); |
| bool is_derived = ((idx - jvms->oopoff()) & 1) == 0; |
| // search upwards through spills and spill phis for AddP |
| worklist.clear(); |
| worklist.push(check); |
| uint k = 0; |
| while( k < worklist.size() ) { |
| check = worklist.at(k); |
| assert(check,"Bad base or derived pointer"); |
| // See PhaseChaitin::find_base_for_derived() for all cases. |
| int isc = check->is_Copy(); |
| if( isc ) { |
| worklist.push(check->in(isc)); |
| } else if( check->is_Phi() ) { |
| for (uint m = 1; m < check->req(); m++) |
| worklist.push(check->in(m)); |
| } else if( check->is_Con() ) { |
| if (is_derived) { |
| // Derived is NULL+offset |
| assert(!is_derived || check->bottom_type()->is_ptr()->ptr() == TypePtr::Null,"Bad derived pointer"); |
| } else { |
| assert(check->bottom_type()->is_ptr()->_offset == 0,"Bad base pointer"); |
| // Base either ConP(NULL) or loadConP |
| if (check->is_Mach()) { |
| assert(check->as_Mach()->ideal_Opcode() == Op_ConP,"Bad base pointer"); |
| } else { |
| assert(check->Opcode() == Op_ConP && |
| check->bottom_type()->is_ptr()->ptr() == TypePtr::Null,"Bad base pointer"); |
| } |
| } |
| } else if( check->bottom_type()->is_ptr()->_offset == 0 ) { |
| if(check->is_Proj() || check->is_Mach() && |
| (check->as_Mach()->ideal_Opcode() == Op_CreateEx || |
| check->as_Mach()->ideal_Opcode() == Op_ThreadLocal || |
| check->as_Mach()->ideal_Opcode() == Op_CMoveP || |
| check->as_Mach()->ideal_Opcode() == Op_CheckCastPP || |
| #ifdef _LP64 |
| UseCompressedOops && check->as_Mach()->ideal_Opcode() == Op_CastPP || |
| UseCompressedOops && check->as_Mach()->ideal_Opcode() == Op_DecodeN || |
| UseCompressedClassPointers && check->as_Mach()->ideal_Opcode() == Op_DecodeNKlass || |
| #endif |
| check->as_Mach()->ideal_Opcode() == Op_LoadP || |
| check->as_Mach()->ideal_Opcode() == Op_LoadKlass)) { |
| // Valid nodes |
| } else { |
| check->dump(); |
| assert(false,"Bad base or derived pointer"); |
| } |
| } else { |
| assert(is_derived,"Bad base pointer"); |
| assert(check->is_Mach() && check->as_Mach()->ideal_Opcode() == Op_AddP,"Bad derived pointer"); |
| } |
| k++; |
| assert(k < 100000,"Derived pointer checking in infinite loop"); |
| } // End while |
| } |
| } // End of check for derived pointers |
| } // End of Kcheck for debug info |
| } // End of if found a safepoint |
| } // End of forall instructions in block |
| } // End of forall blocks |
| #endif |
| } |
| |
| // Verify that graphs and base pointers are still sane. |
| void PhaseChaitin::verify( ResourceArea *a, bool verify_ifg ) const { |
| #ifdef ASSERT |
| if( VerifyOpto || VerifyRegisterAllocator ) { |
| _cfg.verify(); |
| verify_base_ptrs(a); |
| if(verify_ifg) |
| _ifg->verify(this); |
| } |
| #endif |
| } |
| |
| #endif |
