Fri, 07 Mar 2008 11:09:13 -0800
6667605: (Escape Analysis) inline java constructors when EA is on
Summary: java constructors should be inlined to be able scalar replace a new object
Reviewed-by: rasbold
duke@435 | 1 | /* |
duke@435 | 2 | * Copyright 1997-2006 Sun Microsystems, Inc. All Rights Reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
duke@435 | 19 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
duke@435 | 20 | * CA 95054 USA or visit www.sun.com if you need additional information or |
duke@435 | 21 | * have any questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
duke@435 | 25 | // Optimization - Graph Style |
duke@435 | 26 | |
duke@435 | 27 | #include "incls/_precompiled.incl" |
duke@435 | 28 | #include "incls/_block.cpp.incl" |
duke@435 | 29 | |
duke@435 | 30 | |
duke@435 | 31 | //----------------------------------------------------------------------------- |
duke@435 | 32 | void Block_Array::grow( uint i ) { |
duke@435 | 33 | assert(i >= Max(), "must be an overflow"); |
duke@435 | 34 | debug_only(_limit = i+1); |
duke@435 | 35 | if( i < _size ) return; |
duke@435 | 36 | if( !_size ) { |
duke@435 | 37 | _size = 1; |
duke@435 | 38 | _blocks = (Block**)_arena->Amalloc( _size * sizeof(Block*) ); |
duke@435 | 39 | _blocks[0] = NULL; |
duke@435 | 40 | } |
duke@435 | 41 | uint old = _size; |
duke@435 | 42 | while( i >= _size ) _size <<= 1; // Double to fit |
duke@435 | 43 | _blocks = (Block**)_arena->Arealloc( _blocks, old*sizeof(Block*),_size*sizeof(Block*)); |
duke@435 | 44 | Copy::zero_to_bytes( &_blocks[old], (_size-old)*sizeof(Block*) ); |
duke@435 | 45 | } |
duke@435 | 46 | |
duke@435 | 47 | //============================================================================= |
duke@435 | 48 | void Block_List::remove(uint i) { |
duke@435 | 49 | assert(i < _cnt, "index out of bounds"); |
duke@435 | 50 | Copy::conjoint_words_to_lower((HeapWord*)&_blocks[i+1], (HeapWord*)&_blocks[i], ((_cnt-i-1)*sizeof(Block*))); |
duke@435 | 51 | pop(); // shrink list by one block |
duke@435 | 52 | } |
duke@435 | 53 | |
duke@435 | 54 | void Block_List::insert(uint i, Block *b) { |
duke@435 | 55 | push(b); // grow list by one block |
duke@435 | 56 | Copy::conjoint_words_to_higher((HeapWord*)&_blocks[i], (HeapWord*)&_blocks[i+1], ((_cnt-i-1)*sizeof(Block*))); |
duke@435 | 57 | _blocks[i] = b; |
duke@435 | 58 | } |
duke@435 | 59 | |
duke@435 | 60 | |
duke@435 | 61 | //============================================================================= |
duke@435 | 62 | |
duke@435 | 63 | uint Block::code_alignment() { |
duke@435 | 64 | // Check for Root block |
duke@435 | 65 | if( _pre_order == 0 ) return CodeEntryAlignment; |
duke@435 | 66 | // Check for Start block |
duke@435 | 67 | if( _pre_order == 1 ) return InteriorEntryAlignment; |
duke@435 | 68 | // Check for loop alignment |
duke@435 | 69 | Node *h = head(); |
duke@435 | 70 | if( h->is_Loop() && h->as_Loop()->is_inner_loop() ) { |
duke@435 | 71 | // Pre- and post-loops have low trip count so do not bother with |
duke@435 | 72 | // NOPs for align loop head. The constants are hidden from tuning |
duke@435 | 73 | // but only because my "divide by 4" heuristic surely gets nearly |
duke@435 | 74 | // all possible gain (a "do not align at all" heuristic has a |
duke@435 | 75 | // chance of getting a really tiny gain). |
duke@435 | 76 | if( h->is_CountedLoop() && (h->as_CountedLoop()->is_pre_loop() || |
duke@435 | 77 | h->as_CountedLoop()->is_post_loop()) ) |
duke@435 | 78 | return (OptoLoopAlignment > 4) ? (OptoLoopAlignment>>2) : 1; |
duke@435 | 79 | // Loops with low backedge frequency should not be aligned. |
duke@435 | 80 | Node *n = h->in(LoopNode::LoopBackControl)->in(0); |
duke@435 | 81 | if( n->is_MachIf() && n->as_MachIf()->_prob < 0.01 ) { |
duke@435 | 82 | return 1; // Loop does not loop, more often than not! |
duke@435 | 83 | } |
duke@435 | 84 | return OptoLoopAlignment; // Otherwise align loop head |
duke@435 | 85 | } |
duke@435 | 86 | return 1; // no particular alignment |
duke@435 | 87 | } |
duke@435 | 88 | |
duke@435 | 89 | //----------------------------------------------------------------------------- |
duke@435 | 90 | // Compute the size of first 'inst_cnt' instructions in this block. |
duke@435 | 91 | // Return the number of instructions left to compute if the block has |
duke@435 | 92 | // less then 'inst_cnt' instructions. |
duke@435 | 93 | uint Block::compute_first_inst_size(uint& sum_size, uint inst_cnt, |
duke@435 | 94 | PhaseRegAlloc* ra) { |
duke@435 | 95 | uint last_inst = _nodes.size(); |
duke@435 | 96 | for( uint j = 0; j < last_inst && inst_cnt > 0; j++ ) { |
duke@435 | 97 | uint inst_size = _nodes[j]->size(ra); |
duke@435 | 98 | if( inst_size > 0 ) { |
duke@435 | 99 | inst_cnt--; |
duke@435 | 100 | uint sz = sum_size + inst_size; |
duke@435 | 101 | if( sz <= (uint)OptoLoopAlignment ) { |
duke@435 | 102 | // Compute size of instructions which fit into fetch buffer only |
duke@435 | 103 | // since all inst_cnt instructions will not fit even if we align them. |
duke@435 | 104 | sum_size = sz; |
duke@435 | 105 | } else { |
duke@435 | 106 | return 0; |
duke@435 | 107 | } |
duke@435 | 108 | } |
duke@435 | 109 | } |
duke@435 | 110 | return inst_cnt; |
duke@435 | 111 | } |
duke@435 | 112 | |
duke@435 | 113 | //----------------------------------------------------------------------------- |
duke@435 | 114 | uint Block::find_node( const Node *n ) const { |
duke@435 | 115 | for( uint i = 0; i < _nodes.size(); i++ ) { |
duke@435 | 116 | if( _nodes[i] == n ) |
duke@435 | 117 | return i; |
duke@435 | 118 | } |
duke@435 | 119 | ShouldNotReachHere(); |
duke@435 | 120 | return 0; |
duke@435 | 121 | } |
duke@435 | 122 | |
duke@435 | 123 | // Find and remove n from block list |
duke@435 | 124 | void Block::find_remove( const Node *n ) { |
duke@435 | 125 | _nodes.remove(find_node(n)); |
duke@435 | 126 | } |
duke@435 | 127 | |
duke@435 | 128 | //------------------------------is_Empty--------------------------------------- |
duke@435 | 129 | // Return empty status of a block. Empty blocks contain only the head, other |
duke@435 | 130 | // ideal nodes, and an optional trailing goto. |
duke@435 | 131 | int Block::is_Empty() const { |
duke@435 | 132 | |
duke@435 | 133 | // Root or start block is not considered empty |
duke@435 | 134 | if (head()->is_Root() || head()->is_Start()) { |
duke@435 | 135 | return not_empty; |
duke@435 | 136 | } |
duke@435 | 137 | |
duke@435 | 138 | int success_result = completely_empty; |
duke@435 | 139 | int end_idx = _nodes.size()-1; |
duke@435 | 140 | |
duke@435 | 141 | // Check for ending goto |
duke@435 | 142 | if ((end_idx > 0) && (_nodes[end_idx]->is_Goto())) { |
duke@435 | 143 | success_result = empty_with_goto; |
duke@435 | 144 | end_idx--; |
duke@435 | 145 | } |
duke@435 | 146 | |
duke@435 | 147 | // Unreachable blocks are considered empty |
duke@435 | 148 | if (num_preds() <= 1) { |
duke@435 | 149 | return success_result; |
duke@435 | 150 | } |
duke@435 | 151 | |
duke@435 | 152 | // Ideal nodes are allowable in empty blocks: skip them Only MachNodes |
duke@435 | 153 | // turn directly into code, because only MachNodes have non-trivial |
duke@435 | 154 | // emit() functions. |
duke@435 | 155 | while ((end_idx > 0) && !_nodes[end_idx]->is_Mach()) { |
duke@435 | 156 | end_idx--; |
duke@435 | 157 | } |
duke@435 | 158 | |
duke@435 | 159 | // No room for any interesting instructions? |
duke@435 | 160 | if (end_idx == 0) { |
duke@435 | 161 | return success_result; |
duke@435 | 162 | } |
duke@435 | 163 | |
duke@435 | 164 | return not_empty; |
duke@435 | 165 | } |
duke@435 | 166 | |
duke@435 | 167 | //------------------------------has_uncommon_code------------------------------ |
duke@435 | 168 | // Return true if the block's code implies that it is not likely to be |
duke@435 | 169 | // executed infrequently. Check to see if the block ends in a Halt or |
duke@435 | 170 | // a low probability call. |
duke@435 | 171 | bool Block::has_uncommon_code() const { |
duke@435 | 172 | Node* en = end(); |
duke@435 | 173 | |
duke@435 | 174 | if (en->is_Goto()) |
duke@435 | 175 | en = en->in(0); |
duke@435 | 176 | if (en->is_Catch()) |
duke@435 | 177 | en = en->in(0); |
duke@435 | 178 | if (en->is_Proj() && en->in(0)->is_MachCall()) { |
duke@435 | 179 | MachCallNode* call = en->in(0)->as_MachCall(); |
duke@435 | 180 | if (call->cnt() != COUNT_UNKNOWN && call->cnt() <= PROB_UNLIKELY_MAG(4)) { |
duke@435 | 181 | // This is true for slow-path stubs like new_{instance,array}, |
duke@435 | 182 | // slow_arraycopy, complete_monitor_locking, uncommon_trap. |
duke@435 | 183 | // The magic number corresponds to the probability of an uncommon_trap, |
duke@435 | 184 | // even though it is a count not a probability. |
duke@435 | 185 | return true; |
duke@435 | 186 | } |
duke@435 | 187 | } |
duke@435 | 188 | |
duke@435 | 189 | int op = en->is_Mach() ? en->as_Mach()->ideal_Opcode() : en->Opcode(); |
duke@435 | 190 | return op == Op_Halt; |
duke@435 | 191 | } |
duke@435 | 192 | |
duke@435 | 193 | //------------------------------is_uncommon------------------------------------ |
duke@435 | 194 | // True if block is low enough frequency or guarded by a test which |
duke@435 | 195 | // mostly does not go here. |
duke@435 | 196 | bool Block::is_uncommon( Block_Array &bbs ) const { |
duke@435 | 197 | // Initial blocks must never be moved, so are never uncommon. |
duke@435 | 198 | if (head()->is_Root() || head()->is_Start()) return false; |
duke@435 | 199 | |
duke@435 | 200 | // Check for way-low freq |
duke@435 | 201 | if( _freq < BLOCK_FREQUENCY(0.00001f) ) return true; |
duke@435 | 202 | |
duke@435 | 203 | // Look for code shape indicating uncommon_trap or slow path |
duke@435 | 204 | if (has_uncommon_code()) return true; |
duke@435 | 205 | |
duke@435 | 206 | const float epsilon = 0.05f; |
duke@435 | 207 | const float guard_factor = PROB_UNLIKELY_MAG(4) / (1.f - epsilon); |
duke@435 | 208 | uint uncommon_preds = 0; |
duke@435 | 209 | uint freq_preds = 0; |
duke@435 | 210 | uint uncommon_for_freq_preds = 0; |
duke@435 | 211 | |
duke@435 | 212 | for( uint i=1; i<num_preds(); i++ ) { |
duke@435 | 213 | Block* guard = bbs[pred(i)->_idx]; |
duke@435 | 214 | // Check to see if this block follows its guard 1 time out of 10000 |
duke@435 | 215 | // or less. |
duke@435 | 216 | // |
duke@435 | 217 | // See list of magnitude-4 unlikely probabilities in cfgnode.hpp which |
duke@435 | 218 | // we intend to be "uncommon", such as slow-path TLE allocation, |
duke@435 | 219 | // predicted call failure, and uncommon trap triggers. |
duke@435 | 220 | // |
duke@435 | 221 | // Use an epsilon value of 5% to allow for variability in frequency |
duke@435 | 222 | // predictions and floating point calculations. The net effect is |
duke@435 | 223 | // that guard_factor is set to 9500. |
duke@435 | 224 | // |
duke@435 | 225 | // Ignore low-frequency blocks. |
duke@435 | 226 | // The next check is (guard->_freq < 1.e-5 * 9500.). |
duke@435 | 227 | if(guard->_freq*BLOCK_FREQUENCY(guard_factor) < BLOCK_FREQUENCY(0.00001f)) { |
duke@435 | 228 | uncommon_preds++; |
duke@435 | 229 | } else { |
duke@435 | 230 | freq_preds++; |
duke@435 | 231 | if( _freq < guard->_freq * guard_factor ) { |
duke@435 | 232 | uncommon_for_freq_preds++; |
duke@435 | 233 | } |
duke@435 | 234 | } |
duke@435 | 235 | } |
duke@435 | 236 | if( num_preds() > 1 && |
duke@435 | 237 | // The block is uncommon if all preds are uncommon or |
duke@435 | 238 | (uncommon_preds == (num_preds()-1) || |
duke@435 | 239 | // it is uncommon for all frequent preds. |
duke@435 | 240 | uncommon_for_freq_preds == freq_preds) ) { |
duke@435 | 241 | return true; |
duke@435 | 242 | } |
duke@435 | 243 | return false; |
duke@435 | 244 | } |
duke@435 | 245 | |
duke@435 | 246 | //------------------------------dump------------------------------------------- |
duke@435 | 247 | #ifndef PRODUCT |
duke@435 | 248 | void Block::dump_bidx(const Block* orig) const { |
duke@435 | 249 | if (_pre_order) tty->print("B%d",_pre_order); |
duke@435 | 250 | else tty->print("N%d", head()->_idx); |
duke@435 | 251 | |
duke@435 | 252 | if (Verbose && orig != this) { |
duke@435 | 253 | // Dump the original block's idx |
duke@435 | 254 | tty->print(" ("); |
duke@435 | 255 | orig->dump_bidx(orig); |
duke@435 | 256 | tty->print(")"); |
duke@435 | 257 | } |
duke@435 | 258 | } |
duke@435 | 259 | |
duke@435 | 260 | void Block::dump_pred(const Block_Array *bbs, Block* orig) const { |
duke@435 | 261 | if (is_connector()) { |
duke@435 | 262 | for (uint i=1; i<num_preds(); i++) { |
duke@435 | 263 | Block *p = ((*bbs)[pred(i)->_idx]); |
duke@435 | 264 | p->dump_pred(bbs, orig); |
duke@435 | 265 | } |
duke@435 | 266 | } else { |
duke@435 | 267 | dump_bidx(orig); |
duke@435 | 268 | tty->print(" "); |
duke@435 | 269 | } |
duke@435 | 270 | } |
duke@435 | 271 | |
duke@435 | 272 | void Block::dump_head( const Block_Array *bbs ) const { |
duke@435 | 273 | // Print the basic block |
duke@435 | 274 | dump_bidx(this); |
duke@435 | 275 | tty->print(": #\t"); |
duke@435 | 276 | |
duke@435 | 277 | // Print the incoming CFG edges and the outgoing CFG edges |
duke@435 | 278 | for( uint i=0; i<_num_succs; i++ ) { |
duke@435 | 279 | non_connector_successor(i)->dump_bidx(_succs[i]); |
duke@435 | 280 | tty->print(" "); |
duke@435 | 281 | } |
duke@435 | 282 | tty->print("<- "); |
duke@435 | 283 | if( head()->is_block_start() ) { |
duke@435 | 284 | for (uint i=1; i<num_preds(); i++) { |
duke@435 | 285 | Node *s = pred(i); |
duke@435 | 286 | if (bbs) { |
duke@435 | 287 | Block *p = (*bbs)[s->_idx]; |
duke@435 | 288 | p->dump_pred(bbs, p); |
duke@435 | 289 | } else { |
duke@435 | 290 | while (!s->is_block_start()) |
duke@435 | 291 | s = s->in(0); |
duke@435 | 292 | tty->print("N%d ", s->_idx ); |
duke@435 | 293 | } |
duke@435 | 294 | } |
duke@435 | 295 | } else |
duke@435 | 296 | tty->print("BLOCK HEAD IS JUNK "); |
duke@435 | 297 | |
duke@435 | 298 | // Print loop, if any |
duke@435 | 299 | const Block *bhead = this; // Head of self-loop |
duke@435 | 300 | Node *bh = bhead->head(); |
duke@435 | 301 | if( bbs && bh->is_Loop() && !head()->is_Root() ) { |
duke@435 | 302 | LoopNode *loop = bh->as_Loop(); |
duke@435 | 303 | const Block *bx = (*bbs)[loop->in(LoopNode::LoopBackControl)->_idx]; |
duke@435 | 304 | while (bx->is_connector()) { |
duke@435 | 305 | bx = (*bbs)[bx->pred(1)->_idx]; |
duke@435 | 306 | } |
duke@435 | 307 | tty->print("\tLoop: B%d-B%d ", bhead->_pre_order, bx->_pre_order); |
duke@435 | 308 | // Dump any loop-specific bits, especially for CountedLoops. |
duke@435 | 309 | loop->dump_spec(tty); |
duke@435 | 310 | } |
duke@435 | 311 | tty->print(" Freq: %g",_freq); |
duke@435 | 312 | if( Verbose || WizardMode ) { |
duke@435 | 313 | tty->print(" IDom: %d/#%d", _idom ? _idom->_pre_order : 0, _dom_depth); |
duke@435 | 314 | tty->print(" RegPressure: %d",_reg_pressure); |
duke@435 | 315 | tty->print(" IHRP Index: %d",_ihrp_index); |
duke@435 | 316 | tty->print(" FRegPressure: %d",_freg_pressure); |
duke@435 | 317 | tty->print(" FHRP Index: %d",_fhrp_index); |
duke@435 | 318 | } |
duke@435 | 319 | tty->print_cr(""); |
duke@435 | 320 | } |
duke@435 | 321 | |
duke@435 | 322 | void Block::dump() const { dump(0); } |
duke@435 | 323 | |
duke@435 | 324 | void Block::dump( const Block_Array *bbs ) const { |
duke@435 | 325 | dump_head(bbs); |
duke@435 | 326 | uint cnt = _nodes.size(); |
duke@435 | 327 | for( uint i=0; i<cnt; i++ ) |
duke@435 | 328 | _nodes[i]->dump(); |
duke@435 | 329 | tty->print("\n"); |
duke@435 | 330 | } |
duke@435 | 331 | #endif |
duke@435 | 332 | |
duke@435 | 333 | //============================================================================= |
duke@435 | 334 | //------------------------------PhaseCFG--------------------------------------- |
duke@435 | 335 | PhaseCFG::PhaseCFG( Arena *a, RootNode *r, Matcher &m ) : |
duke@435 | 336 | Phase(CFG), |
duke@435 | 337 | _bbs(a), |
duke@435 | 338 | _root(r) |
duke@435 | 339 | #ifndef PRODUCT |
duke@435 | 340 | , _trace_opto_pipelining(TraceOptoPipelining || C->method_has_option("TraceOptoPipelining")) |
duke@435 | 341 | #endif |
duke@435 | 342 | { |
duke@435 | 343 | ResourceMark rm; |
duke@435 | 344 | // I'll need a few machine-specific GotoNodes. Make an Ideal GotoNode, |
duke@435 | 345 | // then Match it into a machine-specific Node. Then clone the machine |
duke@435 | 346 | // Node on demand. |
duke@435 | 347 | Node *x = new (C, 1) GotoNode(NULL); |
duke@435 | 348 | x->init_req(0, x); |
duke@435 | 349 | _goto = m.match_tree(x); |
duke@435 | 350 | assert(_goto != NULL, ""); |
duke@435 | 351 | _goto->set_req(0,_goto); |
duke@435 | 352 | |
duke@435 | 353 | // Build the CFG in Reverse Post Order |
duke@435 | 354 | _num_blocks = build_cfg(); |
duke@435 | 355 | _broot = _bbs[_root->_idx]; |
duke@435 | 356 | } |
duke@435 | 357 | |
duke@435 | 358 | //------------------------------build_cfg-------------------------------------- |
duke@435 | 359 | // Build a proper looking CFG. Make every block begin with either a StartNode |
duke@435 | 360 | // or a RegionNode. Make every block end with either a Goto, If or Return. |
duke@435 | 361 | // The RootNode both starts and ends it's own block. Do this with a recursive |
duke@435 | 362 | // backwards walk over the control edges. |
duke@435 | 363 | uint PhaseCFG::build_cfg() { |
duke@435 | 364 | Arena *a = Thread::current()->resource_area(); |
duke@435 | 365 | VectorSet visited(a); |
duke@435 | 366 | |
duke@435 | 367 | // Allocate stack with enough space to avoid frequent realloc |
duke@435 | 368 | Node_Stack nstack(a, C->unique() >> 1); |
duke@435 | 369 | nstack.push(_root, 0); |
duke@435 | 370 | uint sum = 0; // Counter for blocks |
duke@435 | 371 | |
duke@435 | 372 | while (nstack.is_nonempty()) { |
duke@435 | 373 | // node and in's index from stack's top |
duke@435 | 374 | // 'np' is _root (see above) or RegionNode, StartNode: we push on stack |
duke@435 | 375 | // only nodes which point to the start of basic block (see below). |
duke@435 | 376 | Node *np = nstack.node(); |
duke@435 | 377 | // idx > 0, except for the first node (_root) pushed on stack |
duke@435 | 378 | // at the beginning when idx == 0. |
duke@435 | 379 | // We will use the condition (idx == 0) later to end the build. |
duke@435 | 380 | uint idx = nstack.index(); |
duke@435 | 381 | Node *proj = np->in(idx); |
duke@435 | 382 | const Node *x = proj->is_block_proj(); |
duke@435 | 383 | // Does the block end with a proper block-ending Node? One of Return, |
duke@435 | 384 | // If or Goto? (This check should be done for visited nodes also). |
duke@435 | 385 | if (x == NULL) { // Does not end right... |
duke@435 | 386 | Node *g = _goto->clone(); // Force it to end in a Goto |
duke@435 | 387 | g->set_req(0, proj); |
duke@435 | 388 | np->set_req(idx, g); |
duke@435 | 389 | x = proj = g; |
duke@435 | 390 | } |
duke@435 | 391 | if (!visited.test_set(x->_idx)) { // Visit this block once |
duke@435 | 392 | // Skip any control-pinned middle'in stuff |
duke@435 | 393 | Node *p = proj; |
duke@435 | 394 | do { |
duke@435 | 395 | proj = p; // Update pointer to last Control |
duke@435 | 396 | p = p->in(0); // Move control forward |
duke@435 | 397 | } while( !p->is_block_proj() && |
duke@435 | 398 | !p->is_block_start() ); |
duke@435 | 399 | // Make the block begin with one of Region or StartNode. |
duke@435 | 400 | if( !p->is_block_start() ) { |
duke@435 | 401 | RegionNode *r = new (C, 2) RegionNode( 2 ); |
duke@435 | 402 | r->init_req(1, p); // Insert RegionNode in the way |
duke@435 | 403 | proj->set_req(0, r); // Insert RegionNode in the way |
duke@435 | 404 | p = r; |
duke@435 | 405 | } |
duke@435 | 406 | // 'p' now points to the start of this basic block |
duke@435 | 407 | |
duke@435 | 408 | // Put self in array of basic blocks |
duke@435 | 409 | Block *bb = new (_bbs._arena) Block(_bbs._arena,p); |
duke@435 | 410 | _bbs.map(p->_idx,bb); |
duke@435 | 411 | _bbs.map(x->_idx,bb); |
duke@435 | 412 | if( x != p ) // Only for root is x == p |
duke@435 | 413 | bb->_nodes.push((Node*)x); |
duke@435 | 414 | |
duke@435 | 415 | // Now handle predecessors |
duke@435 | 416 | ++sum; // Count 1 for self block |
duke@435 | 417 | uint cnt = bb->num_preds(); |
duke@435 | 418 | for (int i = (cnt - 1); i > 0; i-- ) { // For all predecessors |
duke@435 | 419 | Node *prevproj = p->in(i); // Get prior input |
duke@435 | 420 | assert( !prevproj->is_Con(), "dead input not removed" ); |
duke@435 | 421 | // Check to see if p->in(i) is a "control-dependent" CFG edge - |
duke@435 | 422 | // i.e., it splits at the source (via an IF or SWITCH) and merges |
duke@435 | 423 | // at the destination (via a many-input Region). |
duke@435 | 424 | // This breaks critical edges. The RegionNode to start the block |
duke@435 | 425 | // will be added when <p,i> is pulled off the node stack |
duke@435 | 426 | if ( cnt > 2 ) { // Merging many things? |
duke@435 | 427 | assert( prevproj== bb->pred(i),""); |
duke@435 | 428 | if(prevproj->is_block_proj() != prevproj) { // Control-dependent edge? |
duke@435 | 429 | // Force a block on the control-dependent edge |
duke@435 | 430 | Node *g = _goto->clone(); // Force it to end in a Goto |
duke@435 | 431 | g->set_req(0,prevproj); |
duke@435 | 432 | p->set_req(i,g); |
duke@435 | 433 | } |
duke@435 | 434 | } |
duke@435 | 435 | nstack.push(p, i); // 'p' is RegionNode or StartNode |
duke@435 | 436 | } |
duke@435 | 437 | } else { // Post-processing visited nodes |
duke@435 | 438 | nstack.pop(); // remove node from stack |
duke@435 | 439 | // Check if it the fist node pushed on stack at the beginning. |
duke@435 | 440 | if (idx == 0) break; // end of the build |
duke@435 | 441 | // Find predecessor basic block |
duke@435 | 442 | Block *pb = _bbs[x->_idx]; |
duke@435 | 443 | // Insert into nodes array, if not already there |
duke@435 | 444 | if( !_bbs.lookup(proj->_idx) ) { |
duke@435 | 445 | assert( x != proj, "" ); |
duke@435 | 446 | // Map basic block of projection |
duke@435 | 447 | _bbs.map(proj->_idx,pb); |
duke@435 | 448 | pb->_nodes.push(proj); |
duke@435 | 449 | } |
duke@435 | 450 | // Insert self as a child of my predecessor block |
duke@435 | 451 | pb->_succs.map(pb->_num_succs++, _bbs[np->_idx]); |
duke@435 | 452 | assert( pb->_nodes[ pb->_nodes.size() - pb->_num_succs ]->is_block_proj(), |
duke@435 | 453 | "too many control users, not a CFG?" ); |
duke@435 | 454 | } |
duke@435 | 455 | } |
duke@435 | 456 | // Return number of basic blocks for all children and self |
duke@435 | 457 | return sum; |
duke@435 | 458 | } |
duke@435 | 459 | |
duke@435 | 460 | //------------------------------insert_goto_at--------------------------------- |
duke@435 | 461 | // Inserts a goto & corresponding basic block between |
duke@435 | 462 | // block[block_no] and its succ_no'th successor block |
duke@435 | 463 | void PhaseCFG::insert_goto_at(uint block_no, uint succ_no) { |
duke@435 | 464 | // get block with block_no |
duke@435 | 465 | assert(block_no < _num_blocks, "illegal block number"); |
duke@435 | 466 | Block* in = _blocks[block_no]; |
duke@435 | 467 | // get successor block succ_no |
duke@435 | 468 | assert(succ_no < in->_num_succs, "illegal successor number"); |
duke@435 | 469 | Block* out = in->_succs[succ_no]; |
duke@435 | 470 | // get ProjNode corresponding to the succ_no'th successor of the in block |
duke@435 | 471 | ProjNode* proj = in->_nodes[in->_nodes.size() - in->_num_succs + succ_no]->as_Proj(); |
duke@435 | 472 | // create region for basic block |
duke@435 | 473 | RegionNode* region = new (C, 2) RegionNode(2); |
duke@435 | 474 | region->init_req(1, proj); |
duke@435 | 475 | // setup corresponding basic block |
duke@435 | 476 | Block* block = new (_bbs._arena) Block(_bbs._arena, region); |
duke@435 | 477 | _bbs.map(region->_idx, block); |
duke@435 | 478 | C->regalloc()->set_bad(region->_idx); |
duke@435 | 479 | // add a goto node |
duke@435 | 480 | Node* gto = _goto->clone(); // get a new goto node |
duke@435 | 481 | gto->set_req(0, region); |
duke@435 | 482 | // add it to the basic block |
duke@435 | 483 | block->_nodes.push(gto); |
duke@435 | 484 | _bbs.map(gto->_idx, block); |
duke@435 | 485 | C->regalloc()->set_bad(gto->_idx); |
duke@435 | 486 | // hook up successor block |
duke@435 | 487 | block->_succs.map(block->_num_succs++, out); |
duke@435 | 488 | // remap successor's predecessors if necessary |
duke@435 | 489 | for (uint i = 1; i < out->num_preds(); i++) { |
duke@435 | 490 | if (out->pred(i) == proj) out->head()->set_req(i, gto); |
duke@435 | 491 | } |
duke@435 | 492 | // remap predecessor's successor to new block |
duke@435 | 493 | in->_succs.map(succ_no, block); |
duke@435 | 494 | // add new basic block to basic block list |
duke@435 | 495 | _blocks.insert(block_no + 1, block); |
duke@435 | 496 | _num_blocks++; |
duke@435 | 497 | } |
duke@435 | 498 | |
duke@435 | 499 | //------------------------------no_flip_branch--------------------------------- |
duke@435 | 500 | // Does this block end in a multiway branch that cannot have the default case |
duke@435 | 501 | // flipped for another case? |
duke@435 | 502 | static bool no_flip_branch( Block *b ) { |
duke@435 | 503 | int branch_idx = b->_nodes.size() - b->_num_succs-1; |
duke@435 | 504 | if( branch_idx < 1 ) return false; |
duke@435 | 505 | Node *bra = b->_nodes[branch_idx]; |
duke@435 | 506 | if( bra->is_Catch() ) return true; |
duke@435 | 507 | if( bra->is_Mach() ) { |
duke@435 | 508 | if( bra->is_MachNullCheck() ) return true; |
duke@435 | 509 | int iop = bra->as_Mach()->ideal_Opcode(); |
duke@435 | 510 | if( iop == Op_FastLock || iop == Op_FastUnlock ) |
duke@435 | 511 | return true; |
duke@435 | 512 | } |
duke@435 | 513 | return false; |
duke@435 | 514 | } |
duke@435 | 515 | |
duke@435 | 516 | //------------------------------convert_NeverBranch_to_Goto-------------------- |
duke@435 | 517 | // Check for NeverBranch at block end. This needs to become a GOTO to the |
duke@435 | 518 | // true target. NeverBranch are treated as a conditional branch that always |
duke@435 | 519 | // goes the same direction for most of the optimizer and are used to give a |
duke@435 | 520 | // fake exit path to infinite loops. At this late stage they need to turn |
duke@435 | 521 | // into Goto's so that when you enter the infinite loop you indeed hang. |
duke@435 | 522 | void PhaseCFG::convert_NeverBranch_to_Goto(Block *b) { |
duke@435 | 523 | // Find true target |
duke@435 | 524 | int end_idx = b->end_idx(); |
duke@435 | 525 | int idx = b->_nodes[end_idx+1]->as_Proj()->_con; |
duke@435 | 526 | Block *succ = b->_succs[idx]; |
duke@435 | 527 | Node* gto = _goto->clone(); // get a new goto node |
duke@435 | 528 | gto->set_req(0, b->head()); |
duke@435 | 529 | Node *bp = b->_nodes[end_idx]; |
duke@435 | 530 | b->_nodes.map(end_idx,gto); // Slam over NeverBranch |
duke@435 | 531 | _bbs.map(gto->_idx, b); |
duke@435 | 532 | C->regalloc()->set_bad(gto->_idx); |
duke@435 | 533 | b->_nodes.pop(); // Yank projections |
duke@435 | 534 | b->_nodes.pop(); // Yank projections |
duke@435 | 535 | b->_succs.map(0,succ); // Map only successor |
duke@435 | 536 | b->_num_succs = 1; |
duke@435 | 537 | // remap successor's predecessors if necessary |
duke@435 | 538 | uint j; |
duke@435 | 539 | for( j = 1; j < succ->num_preds(); j++) |
duke@435 | 540 | if( succ->pred(j)->in(0) == bp ) |
duke@435 | 541 | succ->head()->set_req(j, gto); |
duke@435 | 542 | // Kill alternate exit path |
duke@435 | 543 | Block *dead = b->_succs[1-idx]; |
duke@435 | 544 | for( j = 1; j < dead->num_preds(); j++) |
duke@435 | 545 | if( dead->pred(j)->in(0) == bp ) |
duke@435 | 546 | break; |
duke@435 | 547 | // Scan through block, yanking dead path from |
duke@435 | 548 | // all regions and phis. |
duke@435 | 549 | dead->head()->del_req(j); |
duke@435 | 550 | for( int k = 1; dead->_nodes[k]->is_Phi(); k++ ) |
duke@435 | 551 | dead->_nodes[k]->del_req(j); |
duke@435 | 552 | } |
duke@435 | 553 | |
duke@435 | 554 | //------------------------------MoveToNext------------------------------------- |
duke@435 | 555 | // Helper function to move block bx to the slot following b_index. Return |
duke@435 | 556 | // true if the move is successful, otherwise false |
duke@435 | 557 | bool PhaseCFG::MoveToNext(Block* bx, uint b_index) { |
duke@435 | 558 | if (bx == NULL) return false; |
duke@435 | 559 | |
duke@435 | 560 | // Return false if bx is already scheduled. |
duke@435 | 561 | uint bx_index = bx->_pre_order; |
duke@435 | 562 | if ((bx_index <= b_index) && (_blocks[bx_index] == bx)) { |
duke@435 | 563 | return false; |
duke@435 | 564 | } |
duke@435 | 565 | |
duke@435 | 566 | // Find the current index of block bx on the block list |
duke@435 | 567 | bx_index = b_index + 1; |
duke@435 | 568 | while( bx_index < _num_blocks && _blocks[bx_index] != bx ) bx_index++; |
duke@435 | 569 | assert(_blocks[bx_index] == bx, "block not found"); |
duke@435 | 570 | |
duke@435 | 571 | // If the previous block conditionally falls into bx, return false, |
duke@435 | 572 | // because moving bx will create an extra jump. |
duke@435 | 573 | for(uint k = 1; k < bx->num_preds(); k++ ) { |
duke@435 | 574 | Block* pred = _bbs[bx->pred(k)->_idx]; |
duke@435 | 575 | if (pred == _blocks[bx_index-1]) { |
duke@435 | 576 | if (pred->_num_succs != 1) { |
duke@435 | 577 | return false; |
duke@435 | 578 | } |
duke@435 | 579 | } |
duke@435 | 580 | } |
duke@435 | 581 | |
duke@435 | 582 | // Reinsert bx just past block 'b' |
duke@435 | 583 | _blocks.remove(bx_index); |
duke@435 | 584 | _blocks.insert(b_index + 1, bx); |
duke@435 | 585 | return true; |
duke@435 | 586 | } |
duke@435 | 587 | |
duke@435 | 588 | //------------------------------MoveToEnd-------------------------------------- |
duke@435 | 589 | // Move empty and uncommon blocks to the end. |
duke@435 | 590 | void PhaseCFG::MoveToEnd(Block *b, uint i) { |
duke@435 | 591 | int e = b->is_Empty(); |
duke@435 | 592 | if (e != Block::not_empty) { |
duke@435 | 593 | if (e == Block::empty_with_goto) { |
duke@435 | 594 | // Remove the goto, but leave the block. |
duke@435 | 595 | b->_nodes.pop(); |
duke@435 | 596 | } |
duke@435 | 597 | // Mark this block as a connector block, which will cause it to be |
duke@435 | 598 | // ignored in certain functions such as non_connector_successor(). |
duke@435 | 599 | b->set_connector(); |
duke@435 | 600 | } |
duke@435 | 601 | // Move the empty block to the end, and don't recheck. |
duke@435 | 602 | _blocks.remove(i); |
duke@435 | 603 | _blocks.push(b); |
duke@435 | 604 | } |
duke@435 | 605 | |
duke@435 | 606 | //------------------------------RemoveEmpty------------------------------------ |
duke@435 | 607 | // Remove empty basic blocks and useless branches. |
duke@435 | 608 | void PhaseCFG::RemoveEmpty() { |
duke@435 | 609 | // Move uncommon blocks to the end |
duke@435 | 610 | uint last = _num_blocks; |
duke@435 | 611 | uint i; |
duke@435 | 612 | assert( _blocks[0] == _broot, "" ); |
duke@435 | 613 | for( i = 1; i < last; i++ ) { |
duke@435 | 614 | Block *b = _blocks[i]; |
duke@435 | 615 | |
duke@435 | 616 | // Check for NeverBranch at block end. This needs to become a GOTO to the |
duke@435 | 617 | // true target. NeverBranch are treated as a conditional branch that |
duke@435 | 618 | // always goes the same direction for most of the optimizer and are used |
duke@435 | 619 | // to give a fake exit path to infinite loops. At this late stage they |
duke@435 | 620 | // need to turn into Goto's so that when you enter the infinite loop you |
duke@435 | 621 | // indeed hang. |
duke@435 | 622 | if( b->_nodes[b->end_idx()]->Opcode() == Op_NeverBranch ) |
duke@435 | 623 | convert_NeverBranch_to_Goto(b); |
duke@435 | 624 | |
duke@435 | 625 | // Look for uncommon blocks and move to end. |
duke@435 | 626 | if( b->is_uncommon(_bbs) ) { |
duke@435 | 627 | MoveToEnd(b, i); |
duke@435 | 628 | last--; // No longer check for being uncommon! |
duke@435 | 629 | if( no_flip_branch(b) ) { // Fall-thru case must follow? |
duke@435 | 630 | b = _blocks[i]; // Find the fall-thru block |
duke@435 | 631 | MoveToEnd(b, i); |
duke@435 | 632 | last--; |
duke@435 | 633 | } |
duke@435 | 634 | i--; // backup block counter post-increment |
duke@435 | 635 | } |
duke@435 | 636 | } |
duke@435 | 637 | |
duke@435 | 638 | // Remove empty blocks |
duke@435 | 639 | uint j1; |
duke@435 | 640 | last = _num_blocks; |
duke@435 | 641 | for( i=0; i < last; i++ ) { |
duke@435 | 642 | Block *b = _blocks[i]; |
duke@435 | 643 | if (i > 0) { |
duke@435 | 644 | if (b->is_Empty() != Block::not_empty) { |
duke@435 | 645 | MoveToEnd(b, i); |
duke@435 | 646 | last--; |
duke@435 | 647 | i--; |
duke@435 | 648 | } |
duke@435 | 649 | } |
duke@435 | 650 | } // End of for all blocks |
duke@435 | 651 | |
duke@435 | 652 | // Fixup final control flow for the blocks. Remove jump-to-next |
duke@435 | 653 | // block. If neither arm of a IF follows the conditional branch, we |
duke@435 | 654 | // have to add a second jump after the conditional. We place the |
duke@435 | 655 | // TRUE branch target in succs[0] for both GOTOs and IFs. |
duke@435 | 656 | for( i=0; i < _num_blocks; i++ ) { |
duke@435 | 657 | Block *b = _blocks[i]; |
duke@435 | 658 | b->_pre_order = i; // turn pre-order into block-index |
duke@435 | 659 | |
duke@435 | 660 | // Connector blocks need no further processing. |
duke@435 | 661 | if (b->is_connector()) { |
duke@435 | 662 | assert((i+1) == _num_blocks || _blocks[i+1]->is_connector(), |
duke@435 | 663 | "All connector blocks should sink to the end"); |
duke@435 | 664 | continue; |
duke@435 | 665 | } |
duke@435 | 666 | assert(b->is_Empty() != Block::completely_empty, |
duke@435 | 667 | "Empty blocks should be connectors"); |
duke@435 | 668 | |
duke@435 | 669 | Block *bnext = (i < _num_blocks-1) ? _blocks[i+1] : NULL; |
duke@435 | 670 | Block *bs0 = b->non_connector_successor(0); |
duke@435 | 671 | |
duke@435 | 672 | // Check for multi-way branches where I cannot negate the test to |
duke@435 | 673 | // exchange the true and false targets. |
duke@435 | 674 | if( no_flip_branch( b ) ) { |
duke@435 | 675 | // Find fall through case - if must fall into its target |
duke@435 | 676 | int branch_idx = b->_nodes.size() - b->_num_succs; |
duke@435 | 677 | for (uint j2 = 0; j2 < b->_num_succs; j2++) { |
duke@435 | 678 | const ProjNode* p = b->_nodes[branch_idx + j2]->as_Proj(); |
duke@435 | 679 | if (p->_con == 0) { |
duke@435 | 680 | // successor j2 is fall through case |
duke@435 | 681 | if (b->non_connector_successor(j2) != bnext) { |
duke@435 | 682 | // but it is not the next block => insert a goto |
duke@435 | 683 | insert_goto_at(i, j2); |
duke@435 | 684 | } |
duke@435 | 685 | // Put taken branch in slot 0 |
duke@435 | 686 | if( j2 == 0 && b->_num_succs == 2) { |
duke@435 | 687 | // Flip targets in succs map |
duke@435 | 688 | Block *tbs0 = b->_succs[0]; |
duke@435 | 689 | Block *tbs1 = b->_succs[1]; |
duke@435 | 690 | b->_succs.map( 0, tbs1 ); |
duke@435 | 691 | b->_succs.map( 1, tbs0 ); |
duke@435 | 692 | } |
duke@435 | 693 | break; |
duke@435 | 694 | } |
duke@435 | 695 | } |
duke@435 | 696 | // Remove all CatchProjs |
duke@435 | 697 | for (j1 = 0; j1 < b->_num_succs; j1++) b->_nodes.pop(); |
duke@435 | 698 | |
duke@435 | 699 | } else if (b->_num_succs == 1) { |
duke@435 | 700 | // Block ends in a Goto? |
duke@435 | 701 | if (bnext == bs0) { |
duke@435 | 702 | // We fall into next block; remove the Goto |
duke@435 | 703 | b->_nodes.pop(); |
duke@435 | 704 | } |
duke@435 | 705 | |
duke@435 | 706 | } else if( b->_num_succs == 2 ) { // Block ends in a If? |
duke@435 | 707 | // Get opcode of 1st projection (matches _succs[0]) |
duke@435 | 708 | // Note: Since this basic block has 2 exits, the last 2 nodes must |
duke@435 | 709 | // be projections (in any order), the 3rd last node must be |
duke@435 | 710 | // the IfNode (we have excluded other 2-way exits such as |
duke@435 | 711 | // CatchNodes already). |
duke@435 | 712 | MachNode *iff = b->_nodes[b->_nodes.size()-3]->as_Mach(); |
duke@435 | 713 | ProjNode *proj0 = b->_nodes[b->_nodes.size()-2]->as_Proj(); |
duke@435 | 714 | ProjNode *proj1 = b->_nodes[b->_nodes.size()-1]->as_Proj(); |
duke@435 | 715 | |
duke@435 | 716 | // Assert that proj0 and succs[0] match up. Similarly for proj1 and succs[1]. |
duke@435 | 717 | assert(proj0->raw_out(0) == b->_succs[0]->head(), "Mismatch successor 0"); |
duke@435 | 718 | assert(proj1->raw_out(0) == b->_succs[1]->head(), "Mismatch successor 1"); |
duke@435 | 719 | |
duke@435 | 720 | Block *bs1 = b->non_connector_successor(1); |
duke@435 | 721 | |
duke@435 | 722 | // Check for neither successor block following the current |
duke@435 | 723 | // block ending in a conditional. If so, move one of the |
duke@435 | 724 | // successors after the current one, provided that the |
duke@435 | 725 | // successor was previously unscheduled, but moveable |
duke@435 | 726 | // (i.e., all paths to it involve a branch). |
duke@435 | 727 | if( bnext != bs0 && bnext != bs1 ) { |
duke@435 | 728 | |
duke@435 | 729 | // Choose the more common successor based on the probability |
duke@435 | 730 | // of the conditional branch. |
duke@435 | 731 | Block *bx = bs0; |
duke@435 | 732 | Block *by = bs1; |
duke@435 | 733 | |
duke@435 | 734 | // _prob is the probability of taking the true path. Make |
duke@435 | 735 | // p the probability of taking successor #1. |
duke@435 | 736 | float p = iff->as_MachIf()->_prob; |
duke@435 | 737 | if( proj0->Opcode() == Op_IfTrue ) { |
duke@435 | 738 | p = 1.0 - p; |
duke@435 | 739 | } |
duke@435 | 740 | |
duke@435 | 741 | // Prefer successor #1 if p > 0.5 |
duke@435 | 742 | if (p > PROB_FAIR) { |
duke@435 | 743 | bx = bs1; |
duke@435 | 744 | by = bs0; |
duke@435 | 745 | } |
duke@435 | 746 | |
duke@435 | 747 | // Attempt the more common successor first |
duke@435 | 748 | if (MoveToNext(bx, i)) { |
duke@435 | 749 | bnext = bx; |
duke@435 | 750 | } else if (MoveToNext(by, i)) { |
duke@435 | 751 | bnext = by; |
duke@435 | 752 | } |
duke@435 | 753 | } |
duke@435 | 754 | |
duke@435 | 755 | // Check for conditional branching the wrong way. Negate |
duke@435 | 756 | // conditional, if needed, so it falls into the following block |
duke@435 | 757 | // and branches to the not-following block. |
duke@435 | 758 | |
duke@435 | 759 | // Check for the next block being in succs[0]. We are going to branch |
duke@435 | 760 | // to succs[0], so we want the fall-thru case as the next block in |
duke@435 | 761 | // succs[1]. |
duke@435 | 762 | if (bnext == bs0) { |
duke@435 | 763 | // Fall-thru case in succs[0], so flip targets in succs map |
duke@435 | 764 | Block *tbs0 = b->_succs[0]; |
duke@435 | 765 | Block *tbs1 = b->_succs[1]; |
duke@435 | 766 | b->_succs.map( 0, tbs1 ); |
duke@435 | 767 | b->_succs.map( 1, tbs0 ); |
duke@435 | 768 | // Flip projection for each target |
duke@435 | 769 | { ProjNode *tmp = proj0; proj0 = proj1; proj1 = tmp; } |
duke@435 | 770 | |
duke@435 | 771 | } else if( bnext == bs1 ) { // Fall-thru is already in succs[1] |
duke@435 | 772 | |
duke@435 | 773 | } else { // Else need a double-branch |
duke@435 | 774 | |
duke@435 | 775 | // The existing conditional branch need not change. |
duke@435 | 776 | // Add a unconditional branch to the false target. |
duke@435 | 777 | // Alas, it must appear in its own block and adding a |
duke@435 | 778 | // block this late in the game is complicated. Sigh. |
duke@435 | 779 | insert_goto_at(i, 1); |
duke@435 | 780 | } |
duke@435 | 781 | |
duke@435 | 782 | // Make sure we TRUE branch to the target |
duke@435 | 783 | if( proj0->Opcode() == Op_IfFalse ) |
duke@435 | 784 | iff->negate(); |
duke@435 | 785 | |
duke@435 | 786 | b->_nodes.pop(); // Remove IfFalse & IfTrue projections |
duke@435 | 787 | b->_nodes.pop(); |
duke@435 | 788 | |
duke@435 | 789 | } else { |
duke@435 | 790 | // Multi-exit block, e.g. a switch statement |
duke@435 | 791 | // But we don't need to do anything here |
duke@435 | 792 | } |
duke@435 | 793 | |
duke@435 | 794 | } // End of for all blocks |
duke@435 | 795 | |
duke@435 | 796 | } |
duke@435 | 797 | |
duke@435 | 798 | |
duke@435 | 799 | //------------------------------dump------------------------------------------- |
duke@435 | 800 | #ifndef PRODUCT |
duke@435 | 801 | void PhaseCFG::_dump_cfg( const Node *end, VectorSet &visited ) const { |
duke@435 | 802 | const Node *x = end->is_block_proj(); |
duke@435 | 803 | assert( x, "not a CFG" ); |
duke@435 | 804 | |
duke@435 | 805 | // Do not visit this block again |
duke@435 | 806 | if( visited.test_set(x->_idx) ) return; |
duke@435 | 807 | |
duke@435 | 808 | // Skip through this block |
duke@435 | 809 | const Node *p = x; |
duke@435 | 810 | do { |
duke@435 | 811 | p = p->in(0); // Move control forward |
duke@435 | 812 | assert( !p->is_block_proj() || p->is_Root(), "not a CFG" ); |
duke@435 | 813 | } while( !p->is_block_start() ); |
duke@435 | 814 | |
duke@435 | 815 | // Recursively visit |
duke@435 | 816 | for( uint i=1; i<p->req(); i++ ) |
duke@435 | 817 | _dump_cfg(p->in(i),visited); |
duke@435 | 818 | |
duke@435 | 819 | // Dump the block |
duke@435 | 820 | _bbs[p->_idx]->dump(&_bbs); |
duke@435 | 821 | } |
duke@435 | 822 | |
duke@435 | 823 | void PhaseCFG::dump( ) const { |
duke@435 | 824 | tty->print("\n--- CFG --- %d BBs\n",_num_blocks); |
duke@435 | 825 | if( _blocks.size() ) { // Did we do basic-block layout? |
duke@435 | 826 | for( uint i=0; i<_num_blocks; i++ ) |
duke@435 | 827 | _blocks[i]->dump(&_bbs); |
duke@435 | 828 | } else { // Else do it with a DFS |
duke@435 | 829 | VectorSet visited(_bbs._arena); |
duke@435 | 830 | _dump_cfg(_root,visited); |
duke@435 | 831 | } |
duke@435 | 832 | } |
duke@435 | 833 | |
duke@435 | 834 | void PhaseCFG::dump_headers() { |
duke@435 | 835 | for( uint i = 0; i < _num_blocks; i++ ) { |
duke@435 | 836 | if( _blocks[i] == NULL ) continue; |
duke@435 | 837 | _blocks[i]->dump_head(&_bbs); |
duke@435 | 838 | } |
duke@435 | 839 | } |
duke@435 | 840 | |
duke@435 | 841 | void PhaseCFG::verify( ) const { |
duke@435 | 842 | // Verify sane CFG |
duke@435 | 843 | for( uint i = 0; i < _num_blocks; i++ ) { |
duke@435 | 844 | Block *b = _blocks[i]; |
duke@435 | 845 | uint cnt = b->_nodes.size(); |
duke@435 | 846 | uint j; |
duke@435 | 847 | for( j = 0; j < cnt; j++ ) { |
duke@435 | 848 | Node *n = b->_nodes[j]; |
duke@435 | 849 | assert( _bbs[n->_idx] == b, "" ); |
duke@435 | 850 | if( j >= 1 && n->is_Mach() && |
duke@435 | 851 | n->as_Mach()->ideal_Opcode() == Op_CreateEx ) { |
duke@435 | 852 | assert( j == 1 || b->_nodes[j-1]->is_Phi(), |
duke@435 | 853 | "CreateEx must be first instruction in block" ); |
duke@435 | 854 | } |
duke@435 | 855 | for( uint k = 0; k < n->req(); k++ ) { |
duke@435 | 856 | Node *use = n->in(k); |
duke@435 | 857 | if( use && use != n ) { |
duke@435 | 858 | assert( _bbs[use->_idx] || use->is_Con(), |
duke@435 | 859 | "must have block; constants for debug info ok" ); |
duke@435 | 860 | } |
duke@435 | 861 | } |
duke@435 | 862 | } |
duke@435 | 863 | |
duke@435 | 864 | j = b->end_idx(); |
duke@435 | 865 | Node *bp = (Node*)b->_nodes[b->_nodes.size()-1]->is_block_proj(); |
duke@435 | 866 | assert( bp, "last instruction must be a block proj" ); |
duke@435 | 867 | assert( bp == b->_nodes[j], "wrong number of successors for this block" ); |
duke@435 | 868 | if( bp->is_Catch() ) { |
duke@435 | 869 | while( b->_nodes[--j]->Opcode() == Op_MachProj ) ; |
duke@435 | 870 | assert( b->_nodes[j]->is_Call(), "CatchProj must follow call" ); |
duke@435 | 871 | } |
duke@435 | 872 | else if( bp->is_Mach() && bp->as_Mach()->ideal_Opcode() == Op_If ) { |
duke@435 | 873 | assert( b->_num_succs == 2, "Conditional branch must have two targets"); |
duke@435 | 874 | } |
duke@435 | 875 | } |
duke@435 | 876 | } |
duke@435 | 877 | #endif |
duke@435 | 878 | |
duke@435 | 879 | //============================================================================= |
duke@435 | 880 | //------------------------------UnionFind-------------------------------------- |
duke@435 | 881 | UnionFind::UnionFind( uint max ) : _cnt(max), _max(max), _indices(NEW_RESOURCE_ARRAY(uint,max)) { |
duke@435 | 882 | Copy::zero_to_bytes( _indices, sizeof(uint)*max ); |
duke@435 | 883 | } |
duke@435 | 884 | |
duke@435 | 885 | void UnionFind::extend( uint from_idx, uint to_idx ) { |
duke@435 | 886 | _nesting.check(); |
duke@435 | 887 | if( from_idx >= _max ) { |
duke@435 | 888 | uint size = 16; |
duke@435 | 889 | while( size <= from_idx ) size <<=1; |
duke@435 | 890 | _indices = REALLOC_RESOURCE_ARRAY( uint, _indices, _max, size ); |
duke@435 | 891 | _max = size; |
duke@435 | 892 | } |
duke@435 | 893 | while( _cnt <= from_idx ) _indices[_cnt++] = 0; |
duke@435 | 894 | _indices[from_idx] = to_idx; |
duke@435 | 895 | } |
duke@435 | 896 | |
duke@435 | 897 | void UnionFind::reset( uint max ) { |
duke@435 | 898 | assert( max <= max_uint, "Must fit within uint" ); |
duke@435 | 899 | // Force the Union-Find mapping to be at least this large |
duke@435 | 900 | extend(max,0); |
duke@435 | 901 | // Initialize to be the ID mapping. |
duke@435 | 902 | for( uint i=0; i<_max; i++ ) map(i,i); |
duke@435 | 903 | } |
duke@435 | 904 | |
duke@435 | 905 | //------------------------------Find_compress---------------------------------- |
duke@435 | 906 | // Straight out of Tarjan's union-find algorithm |
duke@435 | 907 | uint UnionFind::Find_compress( uint idx ) { |
duke@435 | 908 | uint cur = idx; |
duke@435 | 909 | uint next = lookup(cur); |
duke@435 | 910 | while( next != cur ) { // Scan chain of equivalences |
duke@435 | 911 | assert( next < cur, "always union smaller" ); |
duke@435 | 912 | cur = next; // until find a fixed-point |
duke@435 | 913 | next = lookup(cur); |
duke@435 | 914 | } |
duke@435 | 915 | // Core of union-find algorithm: update chain of |
duke@435 | 916 | // equivalences to be equal to the root. |
duke@435 | 917 | while( idx != next ) { |
duke@435 | 918 | uint tmp = lookup(idx); |
duke@435 | 919 | map(idx, next); |
duke@435 | 920 | idx = tmp; |
duke@435 | 921 | } |
duke@435 | 922 | return idx; |
duke@435 | 923 | } |
duke@435 | 924 | |
duke@435 | 925 | //------------------------------Find_const------------------------------------- |
duke@435 | 926 | // Like Find above, but no path compress, so bad asymptotic behavior |
duke@435 | 927 | uint UnionFind::Find_const( uint idx ) const { |
duke@435 | 928 | if( idx == 0 ) return idx; // Ignore the zero idx |
duke@435 | 929 | // Off the end? This can happen during debugging dumps |
duke@435 | 930 | // when data structures have not finished being updated. |
duke@435 | 931 | if( idx >= _max ) return idx; |
duke@435 | 932 | uint next = lookup(idx); |
duke@435 | 933 | while( next != idx ) { // Scan chain of equivalences |
duke@435 | 934 | assert( next < idx, "always union smaller" ); |
duke@435 | 935 | idx = next; // until find a fixed-point |
duke@435 | 936 | next = lookup(idx); |
duke@435 | 937 | } |
duke@435 | 938 | return next; |
duke@435 | 939 | } |
duke@435 | 940 | |
duke@435 | 941 | //------------------------------Union------------------------------------------ |
duke@435 | 942 | // union 2 sets together. |
duke@435 | 943 | void UnionFind::Union( uint idx1, uint idx2 ) { |
duke@435 | 944 | uint src = Find(idx1); |
duke@435 | 945 | uint dst = Find(idx2); |
duke@435 | 946 | assert( src, "" ); |
duke@435 | 947 | assert( dst, "" ); |
duke@435 | 948 | assert( src < _max, "oob" ); |
duke@435 | 949 | assert( dst < _max, "oob" ); |
duke@435 | 950 | assert( src < dst, "always union smaller" ); |
duke@435 | 951 | map(dst,src); |
duke@435 | 952 | } |