Mercurial > hg > truffle
annotate src/share/vm/opto/block.cpp @ 10408:836a62f43af9
Merge with http://hg.openjdk.java.net/hsx/hsx25/hotspot/
| author | Doug Simon <doug.simon@oracle.com> |
|---|---|
| date | Wed, 19 Jun 2013 10:45:56 +0200 |
| parents | cc32ccaaf47f |
| children | d1034bd8cefc |
| rev | line source |
|---|---|
| 0 | 1 /* |
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2 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved. |
| 0 | 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 * | |
| 5 * This code is free software; you can redistribute it and/or modify it | |
| 6 * under the terms of the GNU General Public License version 2 only, as | |
| 7 * published by the Free Software Foundation. | |
| 8 * | |
| 9 * This code is distributed in the hope that it will be useful, but WITHOUT | |
| 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 12 * version 2 for more details (a copy is included in the LICENSE file that | |
| 13 * accompanied this code). | |
| 14 * | |
| 15 * You should have received a copy of the GNU General Public License version | |
| 16 * 2 along with this work; if not, write to the Free Software Foundation, | |
| 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | |
| 18 * | |
|
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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20 * or visit www.oracle.com if you need additional information or have any |
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21 * questions. |
| 0 | 22 * |
| 23 */ | |
| 24 | |
| 1972 | 25 #include "precompiled.hpp" |
| 26 #include "libadt/vectset.hpp" | |
| 27 #include "memory/allocation.inline.hpp" | |
| 28 #include "opto/block.hpp" | |
| 29 #include "opto/cfgnode.hpp" | |
| 30 #include "opto/chaitin.hpp" | |
| 31 #include "opto/loopnode.hpp" | |
| 32 #include "opto/machnode.hpp" | |
| 33 #include "opto/matcher.hpp" | |
| 34 #include "opto/opcodes.hpp" | |
| 35 #include "opto/rootnode.hpp" | |
| 36 #include "utilities/copy.hpp" | |
| 0 | 37 |
| 1972 | 38 // Optimization - Graph Style |
| 0 | 39 |
| 40 | |
| 41 //----------------------------------------------------------------------------- | |
| 42 void Block_Array::grow( uint i ) { | |
| 43 assert(i >= Max(), "must be an overflow"); | |
| 44 debug_only(_limit = i+1); | |
| 45 if( i < _size ) return; | |
| 46 if( !_size ) { | |
| 47 _size = 1; | |
| 48 _blocks = (Block**)_arena->Amalloc( _size * sizeof(Block*) ); | |
| 49 _blocks[0] = NULL; | |
| 50 } | |
| 51 uint old = _size; | |
| 52 while( i >= _size ) _size <<= 1; // Double to fit | |
| 53 _blocks = (Block**)_arena->Arealloc( _blocks, old*sizeof(Block*),_size*sizeof(Block*)); | |
| 54 Copy::zero_to_bytes( &_blocks[old], (_size-old)*sizeof(Block*) ); | |
| 55 } | |
| 56 | |
| 57 //============================================================================= | |
| 58 void Block_List::remove(uint i) { | |
| 59 assert(i < _cnt, "index out of bounds"); | |
| 60 Copy::conjoint_words_to_lower((HeapWord*)&_blocks[i+1], (HeapWord*)&_blocks[i], ((_cnt-i-1)*sizeof(Block*))); | |
| 61 pop(); // shrink list by one block | |
| 62 } | |
| 63 | |
| 64 void Block_List::insert(uint i, Block *b) { | |
| 65 push(b); // grow list by one block | |
| 66 Copy::conjoint_words_to_higher((HeapWord*)&_blocks[i], (HeapWord*)&_blocks[i+1], ((_cnt-i-1)*sizeof(Block*))); | |
| 67 _blocks[i] = b; | |
| 68 } | |
| 69 | |
| 418 | 70 #ifndef PRODUCT |
| 71 void Block_List::print() { | |
| 72 for (uint i=0; i < size(); i++) { | |
| 73 tty->print("B%d ", _blocks[i]->_pre_order); | |
| 74 } | |
| 75 tty->print("size = %d\n", size()); | |
| 76 } | |
| 77 #endif | |
| 0 | 78 |
| 79 //============================================================================= | |
| 80 | |
| 81 uint Block::code_alignment() { | |
| 82 // Check for Root block | |
| 3851 | 83 if (_pre_order == 0) return CodeEntryAlignment; |
| 0 | 84 // Check for Start block |
| 3851 | 85 if (_pre_order == 1) return InteriorEntryAlignment; |
| 0 | 86 // Check for loop alignment |
| 3851 | 87 if (has_loop_alignment()) return loop_alignment(); |
| 418 | 88 |
| 3851 | 89 return relocInfo::addr_unit(); // no particular alignment |
| 418 | 90 } |
| 91 | |
| 92 uint Block::compute_loop_alignment() { | |
| 0 | 93 Node *h = head(); |
| 3851 | 94 int unit_sz = relocInfo::addr_unit(); |
| 95 if (h->is_Loop() && h->as_Loop()->is_inner_loop()) { | |
| 0 | 96 // Pre- and post-loops have low trip count so do not bother with |
| 97 // NOPs for align loop head. The constants are hidden from tuning | |
| 98 // but only because my "divide by 4" heuristic surely gets nearly | |
| 99 // all possible gain (a "do not align at all" heuristic has a | |
| 100 // chance of getting a really tiny gain). | |
| 3851 | 101 if (h->is_CountedLoop() && (h->as_CountedLoop()->is_pre_loop() || |
| 102 h->as_CountedLoop()->is_post_loop())) { | |
| 103 return (OptoLoopAlignment > 4*unit_sz) ? (OptoLoopAlignment>>2) : unit_sz; | |
| 104 } | |
| 0 | 105 // Loops with low backedge frequency should not be aligned. |
| 106 Node *n = h->in(LoopNode::LoopBackControl)->in(0); | |
| 3851 | 107 if (n->is_MachIf() && n->as_MachIf()->_prob < 0.01) { |
| 108 return unit_sz; // Loop does not loop, more often than not! | |
| 0 | 109 } |
| 110 return OptoLoopAlignment; // Otherwise align loop head | |
| 111 } | |
| 418 | 112 |
| 3851 | 113 return unit_sz; // no particular alignment |
| 0 | 114 } |
| 115 | |
| 116 //----------------------------------------------------------------------------- | |
| 117 // Compute the size of first 'inst_cnt' instructions in this block. | |
| 118 // Return the number of instructions left to compute if the block has | |
| 418 | 119 // less then 'inst_cnt' instructions. Stop, and return 0 if sum_size |
| 120 // exceeds OptoLoopAlignment. | |
| 0 | 121 uint Block::compute_first_inst_size(uint& sum_size, uint inst_cnt, |
| 122 PhaseRegAlloc* ra) { | |
| 123 uint last_inst = _nodes.size(); | |
| 124 for( uint j = 0; j < last_inst && inst_cnt > 0; j++ ) { | |
| 125 uint inst_size = _nodes[j]->size(ra); | |
| 126 if( inst_size > 0 ) { | |
| 127 inst_cnt--; | |
| 128 uint sz = sum_size + inst_size; | |
| 129 if( sz <= (uint)OptoLoopAlignment ) { | |
| 130 // Compute size of instructions which fit into fetch buffer only | |
| 131 // since all inst_cnt instructions will not fit even if we align them. | |
| 132 sum_size = sz; | |
| 133 } else { | |
| 134 return 0; | |
| 135 } | |
| 136 } | |
| 137 } | |
| 138 return inst_cnt; | |
| 139 } | |
| 140 | |
| 141 //----------------------------------------------------------------------------- | |
| 142 uint Block::find_node( const Node *n ) const { | |
| 143 for( uint i = 0; i < _nodes.size(); i++ ) { | |
| 144 if( _nodes[i] == n ) | |
| 145 return i; | |
| 146 } | |
| 147 ShouldNotReachHere(); | |
| 148 return 0; | |
| 149 } | |
| 150 | |
| 151 // Find and remove n from block list | |
| 152 void Block::find_remove( const Node *n ) { | |
| 153 _nodes.remove(find_node(n)); | |
| 154 } | |
| 155 | |
| 156 //------------------------------is_Empty--------------------------------------- | |
| 157 // Return empty status of a block. Empty blocks contain only the head, other | |
| 158 // ideal nodes, and an optional trailing goto. | |
| 159 int Block::is_Empty() const { | |
| 160 | |
| 161 // Root or start block is not considered empty | |
| 162 if (head()->is_Root() || head()->is_Start()) { | |
| 163 return not_empty; | |
| 164 } | |
| 165 | |
| 166 int success_result = completely_empty; | |
| 167 int end_idx = _nodes.size()-1; | |
| 168 | |
| 169 // Check for ending goto | |
| 3842 | 170 if ((end_idx > 0) && (_nodes[end_idx]->is_MachGoto())) { |
| 0 | 171 success_result = empty_with_goto; |
| 172 end_idx--; | |
| 173 } | |
| 174 | |
| 175 // Unreachable blocks are considered empty | |
| 176 if (num_preds() <= 1) { | |
| 177 return success_result; | |
| 178 } | |
| 179 | |
| 180 // Ideal nodes are allowable in empty blocks: skip them Only MachNodes | |
| 181 // turn directly into code, because only MachNodes have non-trivial | |
| 182 // emit() functions. | |
| 183 while ((end_idx > 0) && !_nodes[end_idx]->is_Mach()) { | |
| 184 end_idx--; | |
| 185 } | |
| 186 | |
| 187 // No room for any interesting instructions? | |
| 188 if (end_idx == 0) { | |
| 189 return success_result; | |
| 190 } | |
| 191 | |
| 192 return not_empty; | |
| 193 } | |
| 194 | |
| 195 //------------------------------has_uncommon_code------------------------------ | |
| 605 | 196 // Return true if the block's code implies that it is likely to be |
| 0 | 197 // executed infrequently. Check to see if the block ends in a Halt or |
| 198 // a low probability call. | |
| 199 bool Block::has_uncommon_code() const { | |
| 200 Node* en = end(); | |
| 201 | |
| 3842 | 202 if (en->is_MachGoto()) |
| 0 | 203 en = en->in(0); |
| 204 if (en->is_Catch()) | |
| 205 en = en->in(0); | |
| 3842 | 206 if (en->is_MachProj() && en->in(0)->is_MachCall()) { |
| 0 | 207 MachCallNode* call = en->in(0)->as_MachCall(); |
| 208 if (call->cnt() != COUNT_UNKNOWN && call->cnt() <= PROB_UNLIKELY_MAG(4)) { | |
| 209 // This is true for slow-path stubs like new_{instance,array}, | |
| 210 // slow_arraycopy, complete_monitor_locking, uncommon_trap. | |
| 211 // The magic number corresponds to the probability of an uncommon_trap, | |
| 212 // even though it is a count not a probability. | |
| 213 return true; | |
| 214 } | |
| 215 } | |
| 216 | |
| 217 int op = en->is_Mach() ? en->as_Mach()->ideal_Opcode() : en->Opcode(); | |
| 218 return op == Op_Halt; | |
| 219 } | |
| 220 | |
| 221 //------------------------------is_uncommon------------------------------------ | |
| 222 // True if block is low enough frequency or guarded by a test which | |
| 223 // mostly does not go here. | |
| 224 bool Block::is_uncommon( Block_Array &bbs ) const { | |
| 225 // Initial blocks must never be moved, so are never uncommon. | |
| 226 if (head()->is_Root() || head()->is_Start()) return false; | |
| 227 | |
| 228 // Check for way-low freq | |
| 229 if( _freq < BLOCK_FREQUENCY(0.00001f) ) return true; | |
| 230 | |
| 231 // Look for code shape indicating uncommon_trap or slow path | |
| 232 if (has_uncommon_code()) return true; | |
| 233 | |
| 234 const float epsilon = 0.05f; | |
| 235 const float guard_factor = PROB_UNLIKELY_MAG(4) / (1.f - epsilon); | |
| 236 uint uncommon_preds = 0; | |
| 237 uint freq_preds = 0; | |
| 238 uint uncommon_for_freq_preds = 0; | |
| 239 | |
| 240 for( uint i=1; i<num_preds(); i++ ) { | |
| 241 Block* guard = bbs[pred(i)->_idx]; | |
| 242 // Check to see if this block follows its guard 1 time out of 10000 | |
| 243 // or less. | |
| 244 // | |
| 245 // See list of magnitude-4 unlikely probabilities in cfgnode.hpp which | |
| 246 // we intend to be "uncommon", such as slow-path TLE allocation, | |
| 247 // predicted call failure, and uncommon trap triggers. | |
| 248 // | |
| 249 // Use an epsilon value of 5% to allow for variability in frequency | |
| 250 // predictions and floating point calculations. The net effect is | |
| 251 // that guard_factor is set to 9500. | |
| 252 // | |
| 253 // Ignore low-frequency blocks. | |
| 254 // The next check is (guard->_freq < 1.e-5 * 9500.). | |
| 255 if(guard->_freq*BLOCK_FREQUENCY(guard_factor) < BLOCK_FREQUENCY(0.00001f)) { | |
| 256 uncommon_preds++; | |
| 257 } else { | |
| 258 freq_preds++; | |
| 259 if( _freq < guard->_freq * guard_factor ) { | |
| 260 uncommon_for_freq_preds++; | |
| 261 } | |
| 262 } | |
| 263 } | |
| 264 if( num_preds() > 1 && | |
| 265 // The block is uncommon if all preds are uncommon or | |
| 266 (uncommon_preds == (num_preds()-1) || | |
| 267 // it is uncommon for all frequent preds. | |
| 268 uncommon_for_freq_preds == freq_preds) ) { | |
| 269 return true; | |
| 270 } | |
| 271 return false; | |
| 272 } | |
| 273 | |
| 274 //------------------------------dump------------------------------------------- | |
| 275 #ifndef PRODUCT | |
| 3851 | 276 void Block::dump_bidx(const Block* orig, outputStream* st) const { |
| 277 if (_pre_order) st->print("B%d",_pre_order); | |
| 278 else st->print("N%d", head()->_idx); | |
| 0 | 279 |
| 280 if (Verbose && orig != this) { | |
| 281 // Dump the original block's idx | |
| 3851 | 282 st->print(" ("); |
| 283 orig->dump_bidx(orig, st); | |
| 284 st->print(")"); | |
| 0 | 285 } |
| 286 } | |
| 287 | |
| 3851 | 288 void Block::dump_pred(const Block_Array *bbs, Block* orig, outputStream* st) const { |
| 0 | 289 if (is_connector()) { |
| 290 for (uint i=1; i<num_preds(); i++) { | |
| 291 Block *p = ((*bbs)[pred(i)->_idx]); | |
| 3851 | 292 p->dump_pred(bbs, orig, st); |
| 0 | 293 } |
| 294 } else { | |
| 3851 | 295 dump_bidx(orig, st); |
| 296 st->print(" "); | |
| 0 | 297 } |
| 298 } | |
| 299 | |
| 3851 | 300 void Block::dump_head( const Block_Array *bbs, outputStream* st ) const { |
| 0 | 301 // Print the basic block |
| 3851 | 302 dump_bidx(this, st); |
| 303 st->print(": #\t"); | |
| 0 | 304 |
| 305 // Print the incoming CFG edges and the outgoing CFG edges | |
| 306 for( uint i=0; i<_num_succs; i++ ) { | |
| 3851 | 307 non_connector_successor(i)->dump_bidx(_succs[i], st); |
| 308 st->print(" "); | |
| 0 | 309 } |
| 3851 | 310 st->print("<- "); |
| 0 | 311 if( head()->is_block_start() ) { |
| 312 for (uint i=1; i<num_preds(); i++) { | |
| 313 Node *s = pred(i); | |
| 314 if (bbs) { | |
| 315 Block *p = (*bbs)[s->_idx]; | |
| 3851 | 316 p->dump_pred(bbs, p, st); |
| 0 | 317 } else { |
| 318 while (!s->is_block_start()) | |
| 319 s = s->in(0); | |
| 3851 | 320 st->print("N%d ", s->_idx ); |
| 0 | 321 } |
| 322 } | |
| 323 } else | |
| 3851 | 324 st->print("BLOCK HEAD IS JUNK "); |
| 0 | 325 |
| 326 // Print loop, if any | |
| 327 const Block *bhead = this; // Head of self-loop | |
| 328 Node *bh = bhead->head(); | |
| 329 if( bbs && bh->is_Loop() && !head()->is_Root() ) { | |
| 330 LoopNode *loop = bh->as_Loop(); | |
| 331 const Block *bx = (*bbs)[loop->in(LoopNode::LoopBackControl)->_idx]; | |
| 332 while (bx->is_connector()) { | |
| 333 bx = (*bbs)[bx->pred(1)->_idx]; | |
| 334 } | |
| 3851 | 335 st->print("\tLoop: B%d-B%d ", bhead->_pre_order, bx->_pre_order); |
| 0 | 336 // Dump any loop-specific bits, especially for CountedLoops. |
| 3851 | 337 loop->dump_spec(st); |
| 418 | 338 } else if (has_loop_alignment()) { |
| 3851 | 339 st->print(" top-of-loop"); |
| 0 | 340 } |
| 3851 | 341 st->print(" Freq: %g",_freq); |
| 0 | 342 if( Verbose || WizardMode ) { |
| 3851 | 343 st->print(" IDom: %d/#%d", _idom ? _idom->_pre_order : 0, _dom_depth); |
| 344 st->print(" RegPressure: %d",_reg_pressure); | |
| 345 st->print(" IHRP Index: %d",_ihrp_index); | |
| 346 st->print(" FRegPressure: %d",_freg_pressure); | |
| 347 st->print(" FHRP Index: %d",_fhrp_index); | |
| 0 | 348 } |
| 3851 | 349 st->print_cr(""); |
| 0 | 350 } |
| 351 | |
| 3851 | 352 void Block::dump() const { dump(NULL); } |
| 0 | 353 |
| 354 void Block::dump( const Block_Array *bbs ) const { | |
| 355 dump_head(bbs); | |
| 356 uint cnt = _nodes.size(); | |
| 357 for( uint i=0; i<cnt; i++ ) | |
| 358 _nodes[i]->dump(); | |
| 359 tty->print("\n"); | |
| 360 } | |
| 361 #endif | |
| 362 | |
| 363 //============================================================================= | |
| 364 //------------------------------PhaseCFG--------------------------------------- | |
| 365 PhaseCFG::PhaseCFG( Arena *a, RootNode *r, Matcher &m ) : | |
| 366 Phase(CFG), | |
| 367 _bbs(a), | |
| 1685 | 368 _root(r), |
| 369 _node_latency(NULL) | |
| 0 | 370 #ifndef PRODUCT |
| 371 , _trace_opto_pipelining(TraceOptoPipelining || C->method_has_option("TraceOptoPipelining")) | |
| 372 #endif | |
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373 #ifdef ASSERT |
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374 , _raw_oops(a) |
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375 #endif |
| 0 | 376 { |
| 377 ResourceMark rm; | |
| 378 // I'll need a few machine-specific GotoNodes. Make an Ideal GotoNode, | |
| 379 // then Match it into a machine-specific Node. Then clone the machine | |
| 380 // Node on demand. | |
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381 Node *x = new (C) GotoNode(NULL); |
| 0 | 382 x->init_req(0, x); |
| 383 _goto = m.match_tree(x); | |
| 384 assert(_goto != NULL, ""); | |
| 385 _goto->set_req(0,_goto); | |
| 386 | |
| 387 // Build the CFG in Reverse Post Order | |
| 388 _num_blocks = build_cfg(); | |
| 389 _broot = _bbs[_root->_idx]; | |
| 390 } | |
| 391 | |
| 392 //------------------------------build_cfg-------------------------------------- | |
| 393 // Build a proper looking CFG. Make every block begin with either a StartNode | |
| 394 // or a RegionNode. Make every block end with either a Goto, If or Return. | |
| 395 // The RootNode both starts and ends it's own block. Do this with a recursive | |
| 396 // backwards walk over the control edges. | |
| 397 uint PhaseCFG::build_cfg() { | |
| 398 Arena *a = Thread::current()->resource_area(); | |
| 399 VectorSet visited(a); | |
| 400 | |
| 401 // Allocate stack with enough space to avoid frequent realloc | |
| 402 Node_Stack nstack(a, C->unique() >> 1); | |
| 403 nstack.push(_root, 0); | |
| 404 uint sum = 0; // Counter for blocks | |
| 405 | |
| 406 while (nstack.is_nonempty()) { | |
| 407 // node and in's index from stack's top | |
| 408 // 'np' is _root (see above) or RegionNode, StartNode: we push on stack | |
| 409 // only nodes which point to the start of basic block (see below). | |
| 410 Node *np = nstack.node(); | |
| 411 // idx > 0, except for the first node (_root) pushed on stack | |
| 412 // at the beginning when idx == 0. | |
| 413 // We will use the condition (idx == 0) later to end the build. | |
| 414 uint idx = nstack.index(); | |
| 415 Node *proj = np->in(idx); | |
| 416 const Node *x = proj->is_block_proj(); | |
| 417 // Does the block end with a proper block-ending Node? One of Return, | |
| 418 // If or Goto? (This check should be done for visited nodes also). | |
| 419 if (x == NULL) { // Does not end right... | |
| 420 Node *g = _goto->clone(); // Force it to end in a Goto | |
| 421 g->set_req(0, proj); | |
| 422 np->set_req(idx, g); | |
| 423 x = proj = g; | |
| 424 } | |
| 425 if (!visited.test_set(x->_idx)) { // Visit this block once | |
| 426 // Skip any control-pinned middle'in stuff | |
| 427 Node *p = proj; | |
| 428 do { | |
| 429 proj = p; // Update pointer to last Control | |
| 430 p = p->in(0); // Move control forward | |
| 431 } while( !p->is_block_proj() && | |
| 432 !p->is_block_start() ); | |
| 433 // Make the block begin with one of Region or StartNode. | |
| 434 if( !p->is_block_start() ) { | |
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435 RegionNode *r = new (C) RegionNode( 2 ); |
| 0 | 436 r->init_req(1, p); // Insert RegionNode in the way |
| 437 proj->set_req(0, r); // Insert RegionNode in the way | |
| 438 p = r; | |
| 439 } | |
| 440 // 'p' now points to the start of this basic block | |
| 441 | |
| 442 // Put self in array of basic blocks | |
| 443 Block *bb = new (_bbs._arena) Block(_bbs._arena,p); | |
| 444 _bbs.map(p->_idx,bb); | |
| 445 _bbs.map(x->_idx,bb); | |
| 3851 | 446 if( x != p ) { // Only for root is x == p |
| 0 | 447 bb->_nodes.push((Node*)x); |
| 3851 | 448 } |
| 0 | 449 // Now handle predecessors |
| 450 ++sum; // Count 1 for self block | |
| 451 uint cnt = bb->num_preds(); | |
| 452 for (int i = (cnt - 1); i > 0; i-- ) { // For all predecessors | |
| 453 Node *prevproj = p->in(i); // Get prior input | |
| 454 assert( !prevproj->is_Con(), "dead input not removed" ); | |
| 455 // Check to see if p->in(i) is a "control-dependent" CFG edge - | |
| 456 // i.e., it splits at the source (via an IF or SWITCH) and merges | |
| 457 // at the destination (via a many-input Region). | |
| 458 // This breaks critical edges. The RegionNode to start the block | |
| 459 // will be added when <p,i> is pulled off the node stack | |
| 460 if ( cnt > 2 ) { // Merging many things? | |
| 461 assert( prevproj== bb->pred(i),""); | |
| 462 if(prevproj->is_block_proj() != prevproj) { // Control-dependent edge? | |
| 463 // Force a block on the control-dependent edge | |
| 464 Node *g = _goto->clone(); // Force it to end in a Goto | |
| 465 g->set_req(0,prevproj); | |
| 466 p->set_req(i,g); | |
| 467 } | |
| 468 } | |
| 469 nstack.push(p, i); // 'p' is RegionNode or StartNode | |
| 470 } | |
| 471 } else { // Post-processing visited nodes | |
| 472 nstack.pop(); // remove node from stack | |
| 473 // Check if it the fist node pushed on stack at the beginning. | |
| 474 if (idx == 0) break; // end of the build | |
| 475 // Find predecessor basic block | |
| 476 Block *pb = _bbs[x->_idx]; | |
| 477 // Insert into nodes array, if not already there | |
| 478 if( !_bbs.lookup(proj->_idx) ) { | |
| 479 assert( x != proj, "" ); | |
| 480 // Map basic block of projection | |
| 481 _bbs.map(proj->_idx,pb); | |
| 482 pb->_nodes.push(proj); | |
| 483 } | |
| 484 // Insert self as a child of my predecessor block | |
| 485 pb->_succs.map(pb->_num_succs++, _bbs[np->_idx]); | |
| 486 assert( pb->_nodes[ pb->_nodes.size() - pb->_num_succs ]->is_block_proj(), | |
| 487 "too many control users, not a CFG?" ); | |
| 488 } | |
| 489 } | |
| 490 // Return number of basic blocks for all children and self | |
| 491 return sum; | |
| 492 } | |
| 493 | |
| 494 //------------------------------insert_goto_at--------------------------------- | |
| 495 // Inserts a goto & corresponding basic block between | |
| 496 // block[block_no] and its succ_no'th successor block | |
| 497 void PhaseCFG::insert_goto_at(uint block_no, uint succ_no) { | |
| 498 // get block with block_no | |
| 499 assert(block_no < _num_blocks, "illegal block number"); | |
| 500 Block* in = _blocks[block_no]; | |
| 501 // get successor block succ_no | |
| 502 assert(succ_no < in->_num_succs, "illegal successor number"); | |
| 503 Block* out = in->_succs[succ_no]; | |
| 308 | 504 // Compute frequency of the new block. Do this before inserting |
| 505 // new block in case succ_prob() needs to infer the probability from | |
| 506 // surrounding blocks. | |
| 507 float freq = in->_freq * in->succ_prob(succ_no); | |
| 0 | 508 // get ProjNode corresponding to the succ_no'th successor of the in block |
| 509 ProjNode* proj = in->_nodes[in->_nodes.size() - in->_num_succs + succ_no]->as_Proj(); | |
| 510 // create region for basic block | |
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511 RegionNode* region = new (C) RegionNode(2); |
| 0 | 512 region->init_req(1, proj); |
| 513 // setup corresponding basic block | |
| 514 Block* block = new (_bbs._arena) Block(_bbs._arena, region); | |
| 515 _bbs.map(region->_idx, block); | |
| 516 C->regalloc()->set_bad(region->_idx); | |
| 517 // add a goto node | |
| 518 Node* gto = _goto->clone(); // get a new goto node | |
| 519 gto->set_req(0, region); | |
| 520 // add it to the basic block | |
| 521 block->_nodes.push(gto); | |
| 522 _bbs.map(gto->_idx, block); | |
| 523 C->regalloc()->set_bad(gto->_idx); | |
| 524 // hook up successor block | |
| 525 block->_succs.map(block->_num_succs++, out); | |
| 526 // remap successor's predecessors if necessary | |
| 527 for (uint i = 1; i < out->num_preds(); i++) { | |
| 528 if (out->pred(i) == proj) out->head()->set_req(i, gto); | |
| 529 } | |
| 530 // remap predecessor's successor to new block | |
| 531 in->_succs.map(succ_no, block); | |
| 308 | 532 // Set the frequency of the new block |
| 533 block->_freq = freq; | |
| 0 | 534 // add new basic block to basic block list |
| 535 _blocks.insert(block_no + 1, block); | |
| 536 _num_blocks++; | |
| 537 } | |
| 538 | |
| 539 //------------------------------no_flip_branch--------------------------------- | |
| 540 // Does this block end in a multiway branch that cannot have the default case | |
| 541 // flipped for another case? | |
| 542 static bool no_flip_branch( Block *b ) { | |
| 543 int branch_idx = b->_nodes.size() - b->_num_succs-1; | |
| 544 if( branch_idx < 1 ) return false; | |
| 545 Node *bra = b->_nodes[branch_idx]; | |
| 418 | 546 if( bra->is_Catch() ) |
| 547 return true; | |
| 0 | 548 if( bra->is_Mach() ) { |
| 418 | 549 if( bra->is_MachNullCheck() ) |
| 550 return true; | |
| 0 | 551 int iop = bra->as_Mach()->ideal_Opcode(); |
| 552 if( iop == Op_FastLock || iop == Op_FastUnlock ) | |
| 553 return true; | |
| 554 } | |
| 555 return false; | |
| 556 } | |
| 557 | |
| 558 //------------------------------convert_NeverBranch_to_Goto-------------------- | |
| 559 // Check for NeverBranch at block end. This needs to become a GOTO to the | |
| 560 // true target. NeverBranch are treated as a conditional branch that always | |
| 561 // goes the same direction for most of the optimizer and are used to give a | |
| 562 // fake exit path to infinite loops. At this late stage they need to turn | |
| 563 // into Goto's so that when you enter the infinite loop you indeed hang. | |
| 564 void PhaseCFG::convert_NeverBranch_to_Goto(Block *b) { | |
| 565 // Find true target | |
| 566 int end_idx = b->end_idx(); | |
| 567 int idx = b->_nodes[end_idx+1]->as_Proj()->_con; | |
| 568 Block *succ = b->_succs[idx]; | |
| 569 Node* gto = _goto->clone(); // get a new goto node | |
| 570 gto->set_req(0, b->head()); | |
| 571 Node *bp = b->_nodes[end_idx]; | |
| 572 b->_nodes.map(end_idx,gto); // Slam over NeverBranch | |
| 573 _bbs.map(gto->_idx, b); | |
| 574 C->regalloc()->set_bad(gto->_idx); | |
| 575 b->_nodes.pop(); // Yank projections | |
| 576 b->_nodes.pop(); // Yank projections | |
| 577 b->_succs.map(0,succ); // Map only successor | |
| 578 b->_num_succs = 1; | |
| 579 // remap successor's predecessors if necessary | |
| 580 uint j; | |
| 581 for( j = 1; j < succ->num_preds(); j++) | |
| 582 if( succ->pred(j)->in(0) == bp ) | |
| 583 succ->head()->set_req(j, gto); | |
| 584 // Kill alternate exit path | |
| 585 Block *dead = b->_succs[1-idx]; | |
| 586 for( j = 1; j < dead->num_preds(); j++) | |
| 587 if( dead->pred(j)->in(0) == bp ) | |
| 588 break; | |
| 589 // Scan through block, yanking dead path from | |
| 590 // all regions and phis. | |
| 591 dead->head()->del_req(j); | |
| 592 for( int k = 1; dead->_nodes[k]->is_Phi(); k++ ) | |
| 593 dead->_nodes[k]->del_req(j); | |
| 594 } | |
| 595 | |
| 418 | 596 //------------------------------move_to_next----------------------------------- |
| 0 | 597 // Helper function to move block bx to the slot following b_index. Return |
| 598 // true if the move is successful, otherwise false | |
| 418 | 599 bool PhaseCFG::move_to_next(Block* bx, uint b_index) { |
| 0 | 600 if (bx == NULL) return false; |
| 601 | |
| 602 // Return false if bx is already scheduled. | |
| 603 uint bx_index = bx->_pre_order; | |
| 604 if ((bx_index <= b_index) && (_blocks[bx_index] == bx)) { | |
| 605 return false; | |
| 606 } | |
| 607 | |
| 608 // Find the current index of block bx on the block list | |
| 609 bx_index = b_index + 1; | |
| 610 while( bx_index < _num_blocks && _blocks[bx_index] != bx ) bx_index++; | |
| 611 assert(_blocks[bx_index] == bx, "block not found"); | |
| 612 | |
| 613 // If the previous block conditionally falls into bx, return false, | |
| 614 // because moving bx will create an extra jump. | |
| 615 for(uint k = 1; k < bx->num_preds(); k++ ) { | |
| 616 Block* pred = _bbs[bx->pred(k)->_idx]; | |
| 617 if (pred == _blocks[bx_index-1]) { | |
| 618 if (pred->_num_succs != 1) { | |
| 619 return false; | |
| 620 } | |
| 621 } | |
| 622 } | |
| 623 | |
| 624 // Reinsert bx just past block 'b' | |
| 625 _blocks.remove(bx_index); | |
| 626 _blocks.insert(b_index + 1, bx); | |
| 627 return true; | |
| 628 } | |
| 629 | |
| 418 | 630 //------------------------------move_to_end------------------------------------ |
| 0 | 631 // Move empty and uncommon blocks to the end. |
| 418 | 632 void PhaseCFG::move_to_end(Block *b, uint i) { |
| 0 | 633 int e = b->is_Empty(); |
| 634 if (e != Block::not_empty) { | |
| 635 if (e == Block::empty_with_goto) { | |
| 636 // Remove the goto, but leave the block. | |
| 637 b->_nodes.pop(); | |
| 638 } | |
| 639 // Mark this block as a connector block, which will cause it to be | |
| 640 // ignored in certain functions such as non_connector_successor(). | |
| 641 b->set_connector(); | |
| 642 } | |
| 643 // Move the empty block to the end, and don't recheck. | |
| 644 _blocks.remove(i); | |
| 645 _blocks.push(b); | |
| 646 } | |
| 647 | |
| 418 | 648 //---------------------------set_loop_alignment-------------------------------- |
| 649 // Set loop alignment for every block | |
| 650 void PhaseCFG::set_loop_alignment() { | |
| 651 uint last = _num_blocks; | |
| 652 assert( _blocks[0] == _broot, "" ); | |
| 653 | |
| 654 for (uint i = 1; i < last; i++ ) { | |
| 655 Block *b = _blocks[i]; | |
| 656 if (b->head()->is_Loop()) { | |
| 657 b->set_loop_alignment(b); | |
| 658 } | |
| 659 } | |
| 660 } | |
| 661 | |
| 662 //-----------------------------remove_empty------------------------------------ | |
| 663 // Make empty basic blocks to be "connector" blocks, Move uncommon blocks | |
| 664 // to the end. | |
| 665 void PhaseCFG::remove_empty() { | |
| 0 | 666 // Move uncommon blocks to the end |
| 667 uint last = _num_blocks; | |
| 668 assert( _blocks[0] == _broot, "" ); | |
| 418 | 669 |
| 670 for (uint i = 1; i < last; i++) { | |
| 0 | 671 Block *b = _blocks[i]; |
| 418 | 672 if (b->is_connector()) break; |
| 0 | 673 |
| 674 // Check for NeverBranch at block end. This needs to become a GOTO to the | |
| 675 // true target. NeverBranch are treated as a conditional branch that | |
| 676 // always goes the same direction for most of the optimizer and are used | |
| 677 // to give a fake exit path to infinite loops. At this late stage they | |
| 678 // need to turn into Goto's so that when you enter the infinite loop you | |
| 679 // indeed hang. | |
| 680 if( b->_nodes[b->end_idx()]->Opcode() == Op_NeverBranch ) | |
| 681 convert_NeverBranch_to_Goto(b); | |
| 682 | |
| 683 // Look for uncommon blocks and move to end. | |
| 418 | 684 if (!C->do_freq_based_layout()) { |
| 685 if( b->is_uncommon(_bbs) ) { | |
| 686 move_to_end(b, i); | |
| 687 last--; // No longer check for being uncommon! | |
| 688 if( no_flip_branch(b) ) { // Fall-thru case must follow? | |
| 689 b = _blocks[i]; // Find the fall-thru block | |
| 690 move_to_end(b, i); | |
| 691 last--; | |
| 692 } | |
| 693 i--; // backup block counter post-increment | |
| 0 | 694 } |
| 695 } | |
| 696 } | |
| 697 | |
| 418 | 698 // Move empty blocks to the end |
| 0 | 699 last = _num_blocks; |
| 418 | 700 for (uint i = 1; i < last; i++) { |
| 0 | 701 Block *b = _blocks[i]; |
| 418 | 702 if (b->is_Empty() != Block::not_empty) { |
| 703 move_to_end(b, i); | |
| 704 last--; | |
| 705 i--; | |
| 0 | 706 } |
| 707 } // End of for all blocks | |
| 418 | 708 } |
| 0 | 709 |
| 418 | 710 //-----------------------------fixup_flow-------------------------------------- |
| 711 // Fix up the final control flow for basic blocks. | |
| 712 void PhaseCFG::fixup_flow() { | |
| 0 | 713 // Fixup final control flow for the blocks. Remove jump-to-next |
| 714 // block. If neither arm of a IF follows the conditional branch, we | |
| 715 // have to add a second jump after the conditional. We place the | |
| 716 // TRUE branch target in succs[0] for both GOTOs and IFs. | |
| 418 | 717 for (uint i=0; i < _num_blocks; i++) { |
| 0 | 718 Block *b = _blocks[i]; |
| 719 b->_pre_order = i; // turn pre-order into block-index | |
| 720 | |
| 721 // Connector blocks need no further processing. | |
| 722 if (b->is_connector()) { | |
| 723 assert((i+1) == _num_blocks || _blocks[i+1]->is_connector(), | |
| 724 "All connector blocks should sink to the end"); | |
| 725 continue; | |
| 726 } | |
| 727 assert(b->is_Empty() != Block::completely_empty, | |
| 728 "Empty blocks should be connectors"); | |
| 729 | |
| 730 Block *bnext = (i < _num_blocks-1) ? _blocks[i+1] : NULL; | |
| 731 Block *bs0 = b->non_connector_successor(0); | |
| 732 | |
| 733 // Check for multi-way branches where I cannot negate the test to | |
| 734 // exchange the true and false targets. | |
| 735 if( no_flip_branch( b ) ) { | |
| 736 // Find fall through case - if must fall into its target | |
| 737 int branch_idx = b->_nodes.size() - b->_num_succs; | |
| 738 for (uint j2 = 0; j2 < b->_num_succs; j2++) { | |
| 739 const ProjNode* p = b->_nodes[branch_idx + j2]->as_Proj(); | |
| 740 if (p->_con == 0) { | |
| 741 // successor j2 is fall through case | |
| 742 if (b->non_connector_successor(j2) != bnext) { | |
| 743 // but it is not the next block => insert a goto | |
| 744 insert_goto_at(i, j2); | |
| 745 } | |
| 746 // Put taken branch in slot 0 | |
| 747 if( j2 == 0 && b->_num_succs == 2) { | |
| 748 // Flip targets in succs map | |
| 749 Block *tbs0 = b->_succs[0]; | |
| 750 Block *tbs1 = b->_succs[1]; | |
| 751 b->_succs.map( 0, tbs1 ); | |
| 752 b->_succs.map( 1, tbs0 ); | |
| 753 } | |
| 754 break; | |
| 755 } | |
| 756 } | |
| 757 // Remove all CatchProjs | |
| 418 | 758 for (uint j1 = 0; j1 < b->_num_succs; j1++) b->_nodes.pop(); |
| 0 | 759 |
| 760 } else if (b->_num_succs == 1) { | |
| 761 // Block ends in a Goto? | |
| 762 if (bnext == bs0) { | |
| 763 // We fall into next block; remove the Goto | |
| 764 b->_nodes.pop(); | |
| 765 } | |
| 766 | |
| 767 } else if( b->_num_succs == 2 ) { // Block ends in a If? | |
| 768 // Get opcode of 1st projection (matches _succs[0]) | |
| 769 // Note: Since this basic block has 2 exits, the last 2 nodes must | |
| 770 // be projections (in any order), the 3rd last node must be | |
| 771 // the IfNode (we have excluded other 2-way exits such as | |
| 772 // CatchNodes already). | |
| 773 MachNode *iff = b->_nodes[b->_nodes.size()-3]->as_Mach(); | |
| 774 ProjNode *proj0 = b->_nodes[b->_nodes.size()-2]->as_Proj(); | |
| 775 ProjNode *proj1 = b->_nodes[b->_nodes.size()-1]->as_Proj(); | |
| 776 | |
| 777 // Assert that proj0 and succs[0] match up. Similarly for proj1 and succs[1]. | |
| 778 assert(proj0->raw_out(0) == b->_succs[0]->head(), "Mismatch successor 0"); | |
| 779 assert(proj1->raw_out(0) == b->_succs[1]->head(), "Mismatch successor 1"); | |
| 780 | |
| 781 Block *bs1 = b->non_connector_successor(1); | |
| 782 | |
| 783 // Check for neither successor block following the current | |
| 784 // block ending in a conditional. If so, move one of the | |
| 785 // successors after the current one, provided that the | |
| 786 // successor was previously unscheduled, but moveable | |
| 787 // (i.e., all paths to it involve a branch). | |
| 418 | 788 if( !C->do_freq_based_layout() && bnext != bs0 && bnext != bs1 ) { |
| 0 | 789 // Choose the more common successor based on the probability |
| 790 // of the conditional branch. | |
| 791 Block *bx = bs0; | |
| 792 Block *by = bs1; | |
| 793 | |
| 794 // _prob is the probability of taking the true path. Make | |
| 795 // p the probability of taking successor #1. | |
| 796 float p = iff->as_MachIf()->_prob; | |
| 797 if( proj0->Opcode() == Op_IfTrue ) { | |
| 798 p = 1.0 - p; | |
| 799 } | |
| 800 | |
| 801 // Prefer successor #1 if p > 0.5 | |
| 802 if (p > PROB_FAIR) { | |
| 803 bx = bs1; | |
| 804 by = bs0; | |
| 805 } | |
| 806 | |
| 807 // Attempt the more common successor first | |
| 418 | 808 if (move_to_next(bx, i)) { |
| 0 | 809 bnext = bx; |
| 418 | 810 } else if (move_to_next(by, i)) { |
| 0 | 811 bnext = by; |
| 812 } | |
| 813 } | |
| 814 | |
| 815 // Check for conditional branching the wrong way. Negate | |
| 816 // conditional, if needed, so it falls into the following block | |
| 817 // and branches to the not-following block. | |
| 818 | |
| 819 // Check for the next block being in succs[0]. We are going to branch | |
| 820 // to succs[0], so we want the fall-thru case as the next block in | |
| 821 // succs[1]. | |
| 822 if (bnext == bs0) { | |
| 823 // Fall-thru case in succs[0], so flip targets in succs map | |
| 824 Block *tbs0 = b->_succs[0]; | |
| 825 Block *tbs1 = b->_succs[1]; | |
| 826 b->_succs.map( 0, tbs1 ); | |
| 827 b->_succs.map( 1, tbs0 ); | |
| 828 // Flip projection for each target | |
| 829 { ProjNode *tmp = proj0; proj0 = proj1; proj1 = tmp; } | |
| 830 | |
| 418 | 831 } else if( bnext != bs1 ) { |
| 832 // Need a double-branch | |
| 0 | 833 // The existing conditional branch need not change. |
| 834 // Add a unconditional branch to the false target. | |
| 835 // Alas, it must appear in its own block and adding a | |
| 836 // block this late in the game is complicated. Sigh. | |
| 837 insert_goto_at(i, 1); | |
| 838 } | |
| 839 | |
| 840 // Make sure we TRUE branch to the target | |
| 418 | 841 if( proj0->Opcode() == Op_IfFalse ) { |
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842 iff->as_MachIf()->negate(); |
| 418 | 843 } |
| 0 | 844 |
| 845 b->_nodes.pop(); // Remove IfFalse & IfTrue projections | |
| 846 b->_nodes.pop(); | |
| 847 | |
| 848 } else { | |
| 849 // Multi-exit block, e.g. a switch statement | |
| 850 // But we don't need to do anything here | |
| 851 } | |
| 852 } // End of for all blocks | |
| 853 } | |
| 854 | |
| 855 | |
| 856 //------------------------------dump------------------------------------------- | |
| 857 #ifndef PRODUCT | |
| 858 void PhaseCFG::_dump_cfg( const Node *end, VectorSet &visited ) const { | |
| 859 const Node *x = end->is_block_proj(); | |
| 860 assert( x, "not a CFG" ); | |
| 861 | |
| 862 // Do not visit this block again | |
| 863 if( visited.test_set(x->_idx) ) return; | |
| 864 | |
| 865 // Skip through this block | |
| 866 const Node *p = x; | |
| 867 do { | |
| 868 p = p->in(0); // Move control forward | |
| 869 assert( !p->is_block_proj() || p->is_Root(), "not a CFG" ); | |
| 870 } while( !p->is_block_start() ); | |
| 871 | |
| 872 // Recursively visit | |
| 873 for( uint i=1; i<p->req(); i++ ) | |
| 874 _dump_cfg(p->in(i),visited); | |
| 875 | |
| 876 // Dump the block | |
| 877 _bbs[p->_idx]->dump(&_bbs); | |
| 878 } | |
| 879 | |
| 880 void PhaseCFG::dump( ) const { | |
| 881 tty->print("\n--- CFG --- %d BBs\n",_num_blocks); | |
| 882 if( _blocks.size() ) { // Did we do basic-block layout? | |
| 883 for( uint i=0; i<_num_blocks; i++ ) | |
| 884 _blocks[i]->dump(&_bbs); | |
| 885 } else { // Else do it with a DFS | |
| 886 VectorSet visited(_bbs._arena); | |
| 887 _dump_cfg(_root,visited); | |
| 888 } | |
| 889 } | |
| 890 | |
| 891 void PhaseCFG::dump_headers() { | |
| 892 for( uint i = 0; i < _num_blocks; i++ ) { | |
| 893 if( _blocks[i] == NULL ) continue; | |
| 894 _blocks[i]->dump_head(&_bbs); | |
| 895 } | |
| 896 } | |
| 897 | |
| 898 void PhaseCFG::verify( ) const { | |
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899 #ifdef ASSERT |
| 0 | 900 // Verify sane CFG |
| 4115 | 901 for (uint i = 0; i < _num_blocks; i++) { |
| 0 | 902 Block *b = _blocks[i]; |
| 903 uint cnt = b->_nodes.size(); | |
| 904 uint j; | |
| 4115 | 905 for (j = 0; j < cnt; j++) { |
| 0 | 906 Node *n = b->_nodes[j]; |
| 907 assert( _bbs[n->_idx] == b, "" ); | |
| 4115 | 908 if (j >= 1 && n->is_Mach() && |
| 909 n->as_Mach()->ideal_Opcode() == Op_CreateEx) { | |
| 910 assert(j == 1 || b->_nodes[j-1]->is_Phi(), | |
| 911 "CreateEx must be first instruction in block"); | |
| 0 | 912 } |
| 4115 | 913 for (uint k = 0; k < n->req(); k++) { |
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914 Node *def = n->in(k); |
| 4115 | 915 if (def && def != n) { |
| 916 assert(_bbs[def->_idx] || def->is_Con(), | |
| 917 "must have block; constants for debug info ok"); | |
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918 // Verify that instructions in the block is in correct order. |
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919 // Uses must follow their definition if they are at the same block. |
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920 // Mostly done to check that MachSpillCopy nodes are placed correctly |
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921 // when CreateEx node is moved in build_ifg_physical(). |
| 4115 | 922 if (_bbs[def->_idx] == b && |
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923 !(b->head()->is_Loop() && n->is_Phi()) && |
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924 // See (+++) comment in reg_split.cpp |
| 4115 | 925 !(n->jvms() != NULL && n->jvms()->is_monitor_use(k))) { |
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926 bool is_loop = false; |
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927 if (n->is_Phi()) { |
| 4115 | 928 for (uint l = 1; l < def->req(); l++) { |
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929 if (n == def->in(l)) { |
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930 is_loop = true; |
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931 break; // Some kind of loop |
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932 } |
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933 } |
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934 } |
| 4115 | 935 assert(is_loop || b->find_node(def) < j, "uses must follow definitions"); |
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936 } |
| 0 | 937 } |
| 938 } | |
| 939 } | |
| 940 | |
| 941 j = b->end_idx(); | |
| 942 Node *bp = (Node*)b->_nodes[b->_nodes.size()-1]->is_block_proj(); | |
| 943 assert( bp, "last instruction must be a block proj" ); | |
| 944 assert( bp == b->_nodes[j], "wrong number of successors for this block" ); | |
| 4115 | 945 if (bp->is_Catch()) { |
| 946 while (b->_nodes[--j]->is_MachProj()) ; | |
| 947 assert(b->_nodes[j]->is_MachCall(), "CatchProj must follow call"); | |
| 948 } else if (bp->is_Mach() && bp->as_Mach()->ideal_Opcode() == Op_If) { | |
| 949 assert(b->_num_succs == 2, "Conditional branch must have two targets"); | |
| 0 | 950 } |
| 951 } | |
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952 #endif |
| 0 | 953 } |
| 954 #endif | |
| 955 | |
| 956 //============================================================================= | |
| 957 //------------------------------UnionFind-------------------------------------- | |
| 958 UnionFind::UnionFind( uint max ) : _cnt(max), _max(max), _indices(NEW_RESOURCE_ARRAY(uint,max)) { | |
| 959 Copy::zero_to_bytes( _indices, sizeof(uint)*max ); | |
| 960 } | |
| 961 | |
| 962 void UnionFind::extend( uint from_idx, uint to_idx ) { | |
| 963 _nesting.check(); | |
| 964 if( from_idx >= _max ) { | |
| 965 uint size = 16; | |
| 966 while( size <= from_idx ) size <<=1; | |
| 967 _indices = REALLOC_RESOURCE_ARRAY( uint, _indices, _max, size ); | |
| 968 _max = size; | |
| 969 } | |
| 970 while( _cnt <= from_idx ) _indices[_cnt++] = 0; | |
| 971 _indices[from_idx] = to_idx; | |
| 972 } | |
| 973 | |
| 974 void UnionFind::reset( uint max ) { | |
| 975 assert( max <= max_uint, "Must fit within uint" ); | |
| 976 // Force the Union-Find mapping to be at least this large | |
| 977 extend(max,0); | |
| 978 // Initialize to be the ID mapping. | |
| 418 | 979 for( uint i=0; i<max; i++ ) map(i,i); |
| 0 | 980 } |
| 981 | |
| 982 //------------------------------Find_compress---------------------------------- | |
| 983 // Straight out of Tarjan's union-find algorithm | |
| 984 uint UnionFind::Find_compress( uint idx ) { | |
| 985 uint cur = idx; | |
| 986 uint next = lookup(cur); | |
| 987 while( next != cur ) { // Scan chain of equivalences | |
| 988 assert( next < cur, "always union smaller" ); | |
| 989 cur = next; // until find a fixed-point | |
| 990 next = lookup(cur); | |
| 991 } | |
| 992 // Core of union-find algorithm: update chain of | |
| 993 // equivalences to be equal to the root. | |
| 994 while( idx != next ) { | |
| 995 uint tmp = lookup(idx); | |
| 996 map(idx, next); | |
| 997 idx = tmp; | |
| 998 } | |
| 999 return idx; | |
| 1000 } | |
| 1001 | |
| 1002 //------------------------------Find_const------------------------------------- | |
| 1003 // Like Find above, but no path compress, so bad asymptotic behavior | |
| 1004 uint UnionFind::Find_const( uint idx ) const { | |
| 1005 if( idx == 0 ) return idx; // Ignore the zero idx | |
| 1006 // Off the end? This can happen during debugging dumps | |
| 1007 // when data structures have not finished being updated. | |
| 1008 if( idx >= _max ) return idx; | |
| 1009 uint next = lookup(idx); | |
| 1010 while( next != idx ) { // Scan chain of equivalences | |
| 1011 idx = next; // until find a fixed-point | |
| 1012 next = lookup(idx); | |
| 1013 } | |
| 1014 return next; | |
| 1015 } | |
| 1016 | |
| 1017 //------------------------------Union------------------------------------------ | |
| 1018 // union 2 sets together. | |
| 1019 void UnionFind::Union( uint idx1, uint idx2 ) { | |
| 1020 uint src = Find(idx1); | |
| 1021 uint dst = Find(idx2); | |
| 1022 assert( src, "" ); | |
| 1023 assert( dst, "" ); | |
| 1024 assert( src < _max, "oob" ); | |
| 1025 assert( dst < _max, "oob" ); | |
| 1026 assert( src < dst, "always union smaller" ); | |
| 1027 map(dst,src); | |
| 1028 } | |
| 418 | 1029 |
| 1030 #ifndef PRODUCT | |
| 1031 void Trace::dump( ) const { | |
| 1032 tty->print_cr("Trace (freq %f)", first_block()->_freq); | |
| 1033 for (Block *b = first_block(); b != NULL; b = next(b)) { | |
| 1034 tty->print(" B%d", b->_pre_order); | |
| 1035 if (b->head()->is_Loop()) { | |
| 1036 tty->print(" (L%d)", b->compute_loop_alignment()); | |
| 1037 } | |
| 1038 if (b->has_loop_alignment()) { | |
| 1039 tty->print(" (T%d)", b->code_alignment()); | |
| 1040 } | |
| 1041 } | |
| 1042 tty->cr(); | |
| 1043 } | |
| 1044 | |
| 1045 void CFGEdge::dump( ) const { | |
| 1046 tty->print(" B%d --> B%d Freq: %f out:%3d%% in:%3d%% State: ", | |
| 1047 from()->_pre_order, to()->_pre_order, freq(), _from_pct, _to_pct); | |
| 1048 switch(state()) { | |
| 1049 case connected: | |
| 1050 tty->print("connected"); | |
| 1051 break; | |
| 1052 case open: | |
| 1053 tty->print("open"); | |
| 1054 break; | |
| 1055 case interior: | |
| 1056 tty->print("interior"); | |
| 1057 break; | |
| 1058 } | |
| 1059 if (infrequent()) { | |
| 1060 tty->print(" infrequent"); | |
| 1061 } | |
| 1062 tty->cr(); | |
| 1063 } | |
| 1064 #endif | |
| 1065 | |
| 1066 //============================================================================= | |
| 1067 | |
| 1068 //------------------------------edge_order------------------------------------- | |
| 1069 // Comparison function for edges | |
| 1070 static int edge_order(CFGEdge **e0, CFGEdge **e1) { | |
| 1071 float freq0 = (*e0)->freq(); | |
| 1072 float freq1 = (*e1)->freq(); | |
| 1073 if (freq0 != freq1) { | |
| 1074 return freq0 > freq1 ? -1 : 1; | |
| 1075 } | |
| 1076 | |
| 1077 int dist0 = (*e0)->to()->_rpo - (*e0)->from()->_rpo; | |
| 1078 int dist1 = (*e1)->to()->_rpo - (*e1)->from()->_rpo; | |
| 1079 | |
| 1080 return dist1 - dist0; | |
| 1081 } | |
| 1082 | |
| 1083 //------------------------------trace_frequency_order-------------------------- | |
| 1084 // Comparison function for edges | |
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1085 extern "C" int trace_frequency_order(const void *p0, const void *p1) { |
| 418 | 1086 Trace *tr0 = *(Trace **) p0; |
| 1087 Trace *tr1 = *(Trace **) p1; | |
| 1088 Block *b0 = tr0->first_block(); | |
| 1089 Block *b1 = tr1->first_block(); | |
| 1090 | |
| 1091 // The trace of connector blocks goes at the end; | |
| 1092 // we only expect one such trace | |
| 1093 if (b0->is_connector() != b1->is_connector()) { | |
| 1094 return b1->is_connector() ? -1 : 1; | |
| 1095 } | |
| 1096 | |
| 1097 // Pull more frequently executed blocks to the beginning | |
| 1098 float freq0 = b0->_freq; | |
| 1099 float freq1 = b1->_freq; | |
| 1100 if (freq0 != freq1) { | |
| 1101 return freq0 > freq1 ? -1 : 1; | |
| 1102 } | |
| 1103 | |
| 1104 int diff = tr0->first_block()->_rpo - tr1->first_block()->_rpo; | |
| 1105 | |
| 1106 return diff; | |
| 1107 } | |
| 1108 | |
| 1109 //------------------------------find_edges------------------------------------- | |
| 1110 // Find edges of interest, i.e, those which can fall through. Presumes that | |
| 1111 // edges which don't fall through are of low frequency and can be generally | |
| 1112 // ignored. Initialize the list of traces. | |
| 1113 void PhaseBlockLayout::find_edges() | |
| 1114 { | |
| 1115 // Walk the blocks, creating edges and Traces | |
| 1116 uint i; | |
| 1117 Trace *tr = NULL; | |
| 1118 for (i = 0; i < _cfg._num_blocks; i++) { | |
| 1119 Block *b = _cfg._blocks[i]; | |
| 1120 tr = new Trace(b, next, prev); | |
| 1121 traces[tr->id()] = tr; | |
| 1122 | |
| 1123 // All connector blocks should be at the end of the list | |
| 1124 if (b->is_connector()) break; | |
| 1125 | |
| 1126 // If this block and the next one have a one-to-one successor | |
| 1127 // predecessor relationship, simply append the next block | |
| 1128 int nfallthru = b->num_fall_throughs(); | |
| 1129 while (nfallthru == 1 && | |
| 1130 b->succ_fall_through(0)) { | |
| 1131 Block *n = b->_succs[0]; | |
| 1132 | |
| 1133 // Skip over single-entry connector blocks, we don't want to | |
| 1134 // add them to the trace. | |
| 1135 while (n->is_connector() && n->num_preds() == 1) { | |
| 1136 n = n->_succs[0]; | |
| 1137 } | |
| 1138 | |
| 1139 // We see a merge point, so stop search for the next block | |
| 1140 if (n->num_preds() != 1) break; | |
| 1141 | |
| 1142 i++; | |
| 1143 assert(n = _cfg._blocks[i], "expecting next block"); | |
| 1144 tr->append(n); | |
| 1145 uf->map(n->_pre_order, tr->id()); | |
| 1146 traces[n->_pre_order] = NULL; | |
| 1147 nfallthru = b->num_fall_throughs(); | |
| 1148 b = n; | |
| 1149 } | |
| 1150 | |
| 1151 if (nfallthru > 0) { | |
| 1152 // Create a CFGEdge for each outgoing | |
| 1153 // edge that could be a fall-through. | |
| 1154 for (uint j = 0; j < b->_num_succs; j++ ) { | |
| 1155 if (b->succ_fall_through(j)) { | |
| 1156 Block *target = b->non_connector_successor(j); | |
| 1157 float freq = b->_freq * b->succ_prob(j); | |
| 1158 int from_pct = (int) ((100 * freq) / b->_freq); | |
| 1159 int to_pct = (int) ((100 * freq) / target->_freq); | |
| 1160 edges->append(new CFGEdge(b, target, freq, from_pct, to_pct)); | |
| 1161 } | |
| 1162 } | |
| 1163 } | |
| 1164 } | |
| 1165 | |
| 1166 // Group connector blocks into one trace | |
| 1167 for (i++; i < _cfg._num_blocks; i++) { | |
| 1168 Block *b = _cfg._blocks[i]; | |
| 1169 assert(b->is_connector(), "connector blocks at the end"); | |
| 1170 tr->append(b); | |
| 1171 uf->map(b->_pre_order, tr->id()); | |
| 1172 traces[b->_pre_order] = NULL; | |
| 1173 } | |
| 1174 } | |
| 1175 | |
| 1176 //------------------------------union_traces---------------------------------- | |
| 1177 // Union two traces together in uf, and null out the trace in the list | |
| 1178 void PhaseBlockLayout::union_traces(Trace* updated_trace, Trace* old_trace) | |
| 1179 { | |
| 1180 uint old_id = old_trace->id(); | |
| 1181 uint updated_id = updated_trace->id(); | |
| 1182 | |
| 1183 uint lo_id = updated_id; | |
| 1184 uint hi_id = old_id; | |
| 1185 | |
| 1186 // If from is greater than to, swap values to meet | |
| 1187 // UnionFind guarantee. | |
| 1188 if (updated_id > old_id) { | |
| 1189 lo_id = old_id; | |
| 1190 hi_id = updated_id; | |
| 1191 | |
| 1192 // Fix up the trace ids | |
| 1193 traces[lo_id] = traces[updated_id]; | |
| 1194 updated_trace->set_id(lo_id); | |
| 1195 } | |
| 1196 | |
| 1197 // Union the lower with the higher and remove the pointer | |
| 1198 // to the higher. | |
| 1199 uf->Union(lo_id, hi_id); | |
| 1200 traces[hi_id] = NULL; | |
| 1201 } | |
| 1202 | |
| 1203 //------------------------------grow_traces------------------------------------- | |
| 1204 // Append traces together via the most frequently executed edges | |
| 1205 void PhaseBlockLayout::grow_traces() | |
| 1206 { | |
| 1207 // Order the edges, and drive the growth of Traces via the most | |
| 1208 // frequently executed edges. | |
| 1209 edges->sort(edge_order); | |
| 1210 for (int i = 0; i < edges->length(); i++) { | |
| 1211 CFGEdge *e = edges->at(i); | |
| 1212 | |
| 1213 if (e->state() != CFGEdge::open) continue; | |
| 1214 | |
| 1215 Block *src_block = e->from(); | |
| 1216 Block *targ_block = e->to(); | |
| 1217 | |
| 1218 // Don't grow traces along backedges? | |
| 1219 if (!BlockLayoutRotateLoops) { | |
| 1220 if (targ_block->_rpo <= src_block->_rpo) { | |
| 1221 targ_block->set_loop_alignment(targ_block); | |
| 1222 continue; | |
| 1223 } | |
| 1224 } | |
| 1225 | |
| 1226 Trace *src_trace = trace(src_block); | |
| 1227 Trace *targ_trace = trace(targ_block); | |
| 1228 | |
| 1229 // If the edge in question can join two traces at their ends, | |
| 1230 // append one trace to the other. | |
| 1231 if (src_trace->last_block() == src_block) { | |
| 1232 if (src_trace == targ_trace) { | |
| 1233 e->set_state(CFGEdge::interior); | |
| 1234 if (targ_trace->backedge(e)) { | |
| 1235 // Reset i to catch any newly eligible edge | |
| 1236 // (Or we could remember the first "open" edge, and reset there) | |
| 1237 i = 0; | |
| 1238 } | |
| 1239 } else if (targ_trace->first_block() == targ_block) { | |
| 1240 e->set_state(CFGEdge::connected); | |
| 1241 src_trace->append(targ_trace); | |
| 1242 union_traces(src_trace, targ_trace); | |
| 1243 } | |
| 1244 } | |
| 1245 } | |
| 1246 } | |
| 1247 | |
| 1248 //------------------------------merge_traces----------------------------------- | |
| 1249 // Embed one trace into another, if the fork or join points are sufficiently | |
| 1250 // balanced. | |
| 1251 void PhaseBlockLayout::merge_traces(bool fall_thru_only) | |
| 1252 { | |
| 1253 // Walk the edge list a another time, looking at unprocessed edges. | |
| 1254 // Fold in diamonds | |
| 1255 for (int i = 0; i < edges->length(); i++) { | |
| 1256 CFGEdge *e = edges->at(i); | |
| 1257 | |
| 1258 if (e->state() != CFGEdge::open) continue; | |
| 1259 if (fall_thru_only) { | |
| 1260 if (e->infrequent()) continue; | |
| 1261 } | |
| 1262 | |
| 1263 Block *src_block = e->from(); | |
| 1264 Trace *src_trace = trace(src_block); | |
| 1265 bool src_at_tail = src_trace->last_block() == src_block; | |
| 1266 | |
| 1267 Block *targ_block = e->to(); | |
| 1268 Trace *targ_trace = trace(targ_block); | |
| 1269 bool targ_at_start = targ_trace->first_block() == targ_block; | |
| 1270 | |
| 1271 if (src_trace == targ_trace) { | |
| 1272 // This may be a loop, but we can't do much about it. | |
| 1273 e->set_state(CFGEdge::interior); | |
| 1274 continue; | |
| 1275 } | |
| 1276 | |
| 1277 if (fall_thru_only) { | |
| 1278 // If the edge links the middle of two traces, we can't do anything. | |
| 1279 // Mark the edge and continue. | |
| 1280 if (!src_at_tail & !targ_at_start) { | |
| 1281 continue; | |
| 1282 } | |
| 1283 | |
| 1284 // Don't grow traces along backedges? | |
| 1285 if (!BlockLayoutRotateLoops && (targ_block->_rpo <= src_block->_rpo)) { | |
| 1286 continue; | |
| 1287 } | |
| 1288 | |
| 1289 // If both ends of the edge are available, why didn't we handle it earlier? | |
| 1290 assert(src_at_tail ^ targ_at_start, "Should have caught this edge earlier."); | |
| 1291 | |
| 1292 if (targ_at_start) { | |
| 1293 // Insert the "targ" trace in the "src" trace if the insertion point | |
| 1294 // is a two way branch. | |
| 1295 // Better profitability check possible, but may not be worth it. | |
| 1296 // Someday, see if the this "fork" has an associated "join"; | |
| 1297 // then make a policy on merging this trace at the fork or join. | |
| 1298 // For example, other things being equal, it may be better to place this | |
| 1299 // trace at the join point if the "src" trace ends in a two-way, but | |
| 1300 // the insertion point is one-way. | |
| 1301 assert(src_block->num_fall_throughs() == 2, "unexpected diamond"); | |
| 1302 e->set_state(CFGEdge::connected); | |
| 1303 src_trace->insert_after(src_block, targ_trace); | |
| 1304 union_traces(src_trace, targ_trace); | |
| 1305 } else if (src_at_tail) { | |
| 1306 if (src_trace != trace(_cfg._broot)) { | |
| 1307 e->set_state(CFGEdge::connected); | |
| 1308 targ_trace->insert_before(targ_block, src_trace); | |
| 1309 union_traces(targ_trace, src_trace); | |
| 1310 } | |
| 1311 } | |
| 1312 } else if (e->state() == CFGEdge::open) { | |
| 1313 // Append traces, even without a fall-thru connection. | |
| 605 | 1314 // But leave root entry at the beginning of the block list. |
| 418 | 1315 if (targ_trace != trace(_cfg._broot)) { |
| 1316 e->set_state(CFGEdge::connected); | |
| 1317 src_trace->append(targ_trace); | |
| 1318 union_traces(src_trace, targ_trace); | |
| 1319 } | |
| 1320 } | |
| 1321 } | |
| 1322 } | |
| 1323 | |
| 1324 //----------------------------reorder_traces----------------------------------- | |
| 1325 // Order the sequence of the traces in some desirable way, and fixup the | |
| 1326 // jumps at the end of each block. | |
| 1327 void PhaseBlockLayout::reorder_traces(int count) | |
| 1328 { | |
| 1329 ResourceArea *area = Thread::current()->resource_area(); | |
| 1330 Trace ** new_traces = NEW_ARENA_ARRAY(area, Trace *, count); | |
| 1331 Block_List worklist; | |
| 1332 int new_count = 0; | |
| 1333 | |
| 1334 // Compact the traces. | |
| 1335 for (int i = 0; i < count; i++) { | |
| 1336 Trace *tr = traces[i]; | |
| 1337 if (tr != NULL) { | |
| 1338 new_traces[new_count++] = tr; | |
| 1339 } | |
| 1340 } | |
| 1341 | |
| 1342 // The entry block should be first on the new trace list. | |
| 1343 Trace *tr = trace(_cfg._broot); | |
| 1344 assert(tr == new_traces[0], "entry trace misplaced"); | |
| 1345 | |
| 1346 // Sort the new trace list by frequency | |
| 1347 qsort(new_traces + 1, new_count - 1, sizeof(new_traces[0]), trace_frequency_order); | |
| 1348 | |
| 1349 // Patch up the successor blocks | |
| 1350 _cfg._blocks.reset(); | |
| 1351 _cfg._num_blocks = 0; | |
| 1352 for (int i = 0; i < new_count; i++) { | |
| 1353 Trace *tr = new_traces[i]; | |
| 1354 if (tr != NULL) { | |
| 1355 tr->fixup_blocks(_cfg); | |
| 1356 } | |
| 1357 } | |
| 1358 } | |
| 1359 | |
| 1360 //------------------------------PhaseBlockLayout------------------------------- | |
| 1361 // Order basic blocks based on frequency | |
| 1362 PhaseBlockLayout::PhaseBlockLayout(PhaseCFG &cfg) : | |
| 1363 Phase(BlockLayout), | |
| 1364 _cfg(cfg) | |
| 1365 { | |
| 1366 ResourceMark rm; | |
| 1367 ResourceArea *area = Thread::current()->resource_area(); | |
| 1368 | |
| 1369 // List of traces | |
| 1370 int size = _cfg._num_blocks + 1; | |
| 1371 traces = NEW_ARENA_ARRAY(area, Trace *, size); | |
| 1372 memset(traces, 0, size*sizeof(Trace*)); | |
| 1373 next = NEW_ARENA_ARRAY(area, Block *, size); | |
| 1374 memset(next, 0, size*sizeof(Block *)); | |
| 1375 prev = NEW_ARENA_ARRAY(area, Block *, size); | |
| 1376 memset(prev , 0, size*sizeof(Block *)); | |
| 1377 | |
| 1378 // List of edges | |
| 1379 edges = new GrowableArray<CFGEdge*>; | |
| 1380 | |
| 1381 // Mapping block index --> block_trace | |
| 1382 uf = new UnionFind(size); | |
| 1383 uf->reset(size); | |
| 1384 | |
| 1385 // Find edges and create traces. | |
| 1386 find_edges(); | |
| 1387 | |
| 1388 // Grow traces at their ends via most frequent edges. | |
| 1389 grow_traces(); | |
| 1390 | |
| 1391 // Merge one trace into another, but only at fall-through points. | |
| 1392 // This may make diamonds and other related shapes in a trace. | |
| 1393 merge_traces(true); | |
| 1394 | |
| 1395 // Run merge again, allowing two traces to be catenated, even if | |
| 1396 // one does not fall through into the other. This appends loosely | |
| 1397 // related traces to be near each other. | |
| 1398 merge_traces(false); | |
| 1399 | |
| 1400 // Re-order all the remaining traces by frequency | |
| 1401 reorder_traces(size); | |
| 1402 | |
| 1403 assert(_cfg._num_blocks >= (uint) (size - 1), "number of blocks can not shrink"); | |
| 1404 } | |
| 1405 | |
| 1406 | |
| 1407 //------------------------------backedge--------------------------------------- | |
| 1408 // Edge e completes a loop in a trace. If the target block is head of the | |
| 1409 // loop, rotate the loop block so that the loop ends in a conditional branch. | |
| 1410 bool Trace::backedge(CFGEdge *e) { | |
| 1411 bool loop_rotated = false; | |
| 1412 Block *src_block = e->from(); | |
| 1413 Block *targ_block = e->to(); | |
| 1414 | |
| 1415 assert(last_block() == src_block, "loop discovery at back branch"); | |
| 1416 if (first_block() == targ_block) { | |
| 1417 if (BlockLayoutRotateLoops && last_block()->num_fall_throughs() < 2) { | |
| 1418 // Find the last block in the trace that has a conditional | |
| 1419 // branch. | |
| 1420 Block *b; | |
| 1421 for (b = last_block(); b != NULL; b = prev(b)) { | |
| 1422 if (b->num_fall_throughs() == 2) { | |
| 1423 break; | |
| 1424 } | |
| 1425 } | |
| 1426 | |
| 1427 if (b != last_block() && b != NULL) { | |
| 1428 loop_rotated = true; | |
| 1429 | |
| 1430 // Rotate the loop by doing two-part linked-list surgery. | |
| 1431 append(first_block()); | |
| 1432 break_loop_after(b); | |
| 1433 } | |
| 1434 } | |
| 1435 | |
| 1436 // Backbranch to the top of a trace | |
| 605 | 1437 // Scroll forward through the trace from the targ_block. If we find |
| 418 | 1438 // a loop head before another loop top, use the the loop head alignment. |
| 1439 for (Block *b = targ_block; b != NULL; b = next(b)) { | |
| 1440 if (b->has_loop_alignment()) { | |
| 1441 break; | |
| 1442 } | |
| 1443 if (b->head()->is_Loop()) { | |
| 1444 targ_block = b; | |
| 1445 break; | |
| 1446 } | |
| 1447 } | |
| 1448 | |
| 1449 first_block()->set_loop_alignment(targ_block); | |
| 1450 | |
| 1451 } else { | |
| 1452 // Backbranch into the middle of a trace | |
| 1453 targ_block->set_loop_alignment(targ_block); | |
| 1454 } | |
| 1455 | |
| 1456 return loop_rotated; | |
| 1457 } | |
| 1458 | |
| 1459 //------------------------------fixup_blocks----------------------------------- | |
| 1460 // push blocks onto the CFG list | |
| 1461 // ensure that blocks have the correct two-way branch sense | |
| 1462 void Trace::fixup_blocks(PhaseCFG &cfg) { | |
| 1463 Block *last = last_block(); | |
| 1464 for (Block *b = first_block(); b != NULL; b = next(b)) { | |
| 1465 cfg._blocks.push(b); | |
| 1466 cfg._num_blocks++; | |
| 1467 if (!b->is_connector()) { | |
| 1468 int nfallthru = b->num_fall_throughs(); | |
| 1469 if (b != last) { | |
| 1470 if (nfallthru == 2) { | |
| 1471 // Ensure that the sense of the branch is correct | |
| 1472 Block *bnext = next(b); | |
| 1473 Block *bs0 = b->non_connector_successor(0); | |
| 1474 | |
| 1475 MachNode *iff = b->_nodes[b->_nodes.size()-3]->as_Mach(); | |
| 1476 ProjNode *proj0 = b->_nodes[b->_nodes.size()-2]->as_Proj(); | |
| 1477 ProjNode *proj1 = b->_nodes[b->_nodes.size()-1]->as_Proj(); | |
| 1478 | |
| 1479 if (bnext == bs0) { | |
| 1480 // Fall-thru case in succs[0], should be in succs[1] | |
| 1481 | |
| 1482 // Flip targets in _succs map | |
| 1483 Block *tbs0 = b->_succs[0]; | |
| 1484 Block *tbs1 = b->_succs[1]; | |
| 1485 b->_succs.map( 0, tbs1 ); | |
| 1486 b->_succs.map( 1, tbs0 ); | |
| 1487 | |
| 1488 // Flip projections to match targets | |
| 1489 b->_nodes.map(b->_nodes.size()-2, proj1); | |
| 1490 b->_nodes.map(b->_nodes.size()-1, proj0); | |
| 1491 } | |
| 1492 } | |
| 1493 } | |
| 1494 } | |
| 1495 } | |
| 1496 } |