--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/opto/live.cpp Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,314 @@
+/*
+ * Copyright 1997-2005 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+#include "incls/_precompiled.incl"
+#include "incls/_live.cpp.incl"
+
+
+
+//=============================================================================
+//------------------------------PhaseLive--------------------------------------
+// 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 seperate compilation is done in the outer loop below.
+PhaseLive::PhaseLive( const PhaseCFG &cfg, 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._num_blocks);
+ uint i;
+ for( i=0; i<_cfg._num_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._num_blocks);
+ for( i=0; i<_cfg._num_blocks; i++ ) {
+ _defs[i].initialize(_maxlrg);
+ }
+
+ // Array of delta-set pointers, indexed by block pre_order-1.
+ _deltas = NEW_RESOURCE_ARRAY(IndexSet*,_cfg._num_blocks);
+ memset( _deltas, 0, sizeof(IndexSet*)* _cfg._num_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.
+ uint iters = _cfg._num_blocks; // stat counters
+ for( uint j=_cfg._num_blocks; j>0; j-- ) {
+ Block *b = _cfg._blocks[j-1];
+
+ // Compute the local live-in set. Start with any new live-out bits.
+ IndexSet *use = getset( b );
+ IndexSet *def = &_defs[b->_pre_order-1];
+ DEBUG_ONLY(IndexSet *def_outside = getfreeset();)
+ uint i;
+ for( i=b->_nodes.size(); i>1; i-- ) {
+ Node *n = b->_nodes[i-1];
+ if( n->is_Phi() ) break;
+
+ uint r = _names[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._bbs[nkidx] != b ) {
+ uint u = _names[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[b->_nodes[k-1]->_idx];
+ def->insert( r );
+ use->remove( r );
+ }
+
+ // Push these live-in things to predecessors
+ for( uint l=1; l<b->num_preds(); l++ ) {
+ Block *p = _cfg._bbs[b->pred(l)->_idx];
+ 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[b->_nodes[k-1]->in(l)->_idx], first_pass );
+ }
+ freeset( b );
+ first_pass.set(b->_pre_order);
+
+ // Inner loop: blocks that picked up new live-out values to be propagated
+ while( _worklist->size() ) {
+ // !!!!!
+// #ifdef ASSERT
+ iters++;
+// #endif
+ Block *b = _worklist->pop();
+ IndexSet *delta = getset(b);
+ assert( delta->count(), "missing delta set" );
+
+ // Add new-live-in to predecessors live-out sets
+ for( uint l=1; l<b->num_preds(); l++ )
+ add_liveout( _cfg._bbs[b->pred(l)->_idx], delta, first_pass );
+
+ freeset(b);
+ } // 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._num_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();
+ }
+
+}
+
+//------------------------------stats------------------------------------------
+#ifndef PRODUCT
+void PhaseLive::stats(uint iters) const {
+}
+#endif
+
+//------------------------------getset-----------------------------------------
+// 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
+}
+
+//------------------------------getfreeset-------------------------------------
+// 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;
+}
+
+//------------------------------freeset----------------------------------------
+// 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_liveout------------------------------------
+// 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_liveout------------------------------------
+// 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-------------------------------------------
+// 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->_nodes.size();
+ for( uint i=0; i<cnt; i++ ) {
+ tty->print("L%d/", _names[b->_nodes[i]->_idx] );
+ b->_nodes[i]->dump();
+ }
+ tty->print("\n");
+}
+
+//------------------------------verify_base_ptrs-------------------------------
+// Verify that base pointers and derived pointers are still sane.
+// Basically, if a derived pointer is live at a safepoint, then its
+// base pointer must be live also.
+void PhaseChaitin::verify_base_ptrs( ResourceArea *a ) const {
+ for( uint i = 0; i < _cfg._num_blocks; i++ ) {
+ Block *b = _cfg._blocks[i];
+ for( uint j = b->end_idx() + 1; j > 1; j-- ) {
+ Node *n = b->_nodes[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 += 2) {
+ Node *check = sfpt->in(idx);
+ uint j = 0;
+ // search upwards through spills and spill phis for AddP
+ while(true) {
+ if( !check ) break;
+ int idx = check->is_Copy();
+ if( idx ) {
+ check = check->in(idx);
+ } else if( check->is_Phi() && check->_idx >= _oldphi ) {
+ check = check->in(1);
+ } else
+ break;
+ j++;
+ assert(j < 100000,"Derived pointer checking in infinite loop");
+ } // End while
+ assert(check->is_Mach() && check->as_Mach()->ideal_Opcode() == Op_AddP,"Bad derived pointer")
+ }
+ } // 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