Thu, 24 May 2018 18:41:44 +0800
Merge
aoqi@0 | 1 | /* |
aoqi@0 | 2 | * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved. |
aoqi@0 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
aoqi@0 | 4 | * |
aoqi@0 | 5 | * This code is free software; you can redistribute it and/or modify it |
aoqi@0 | 6 | * under the terms of the GNU General Public License version 2 only, as |
aoqi@0 | 7 | * published by the Free Software Foundation. |
aoqi@0 | 8 | * |
aoqi@0 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
aoqi@0 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
aoqi@0 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
aoqi@0 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
aoqi@0 | 13 | * accompanied this code). |
aoqi@0 | 14 | * |
aoqi@0 | 15 | * You should have received a copy of the GNU General Public License version |
aoqi@0 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
aoqi@0 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
aoqi@0 | 18 | * |
aoqi@0 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
aoqi@0 | 20 | * or visit www.oracle.com if you need additional information or have any |
aoqi@0 | 21 | * questions. |
aoqi@0 | 22 | * |
aoqi@0 | 23 | */ |
aoqi@0 | 24 | |
aoqi@0 | 25 | #include "precompiled.hpp" |
aoqi@0 | 26 | #include "c1/c1_Compilation.hpp" |
aoqi@0 | 27 | #include "c1/c1_FrameMap.hpp" |
aoqi@0 | 28 | #include "c1/c1_GraphBuilder.hpp" |
aoqi@0 | 29 | #include "c1/c1_IR.hpp" |
aoqi@0 | 30 | #include "c1/c1_InstructionPrinter.hpp" |
aoqi@0 | 31 | #include "c1/c1_Optimizer.hpp" |
aoqi@0 | 32 | #include "utilities/bitMap.inline.hpp" |
aoqi@0 | 33 | |
aoqi@0 | 34 | |
aoqi@0 | 35 | // Implementation of XHandlers |
aoqi@0 | 36 | // |
aoqi@0 | 37 | // Note: This code could eventually go away if we are |
aoqi@0 | 38 | // just using the ciExceptionHandlerStream. |
aoqi@0 | 39 | |
aoqi@0 | 40 | XHandlers::XHandlers(ciMethod* method) : _list(method->exception_table_length()) { |
aoqi@0 | 41 | ciExceptionHandlerStream s(method); |
aoqi@0 | 42 | while (!s.is_done()) { |
aoqi@0 | 43 | _list.append(new XHandler(s.handler())); |
aoqi@0 | 44 | s.next(); |
aoqi@0 | 45 | } |
aoqi@0 | 46 | assert(s.count() == method->exception_table_length(), "exception table lengths inconsistent"); |
aoqi@0 | 47 | } |
aoqi@0 | 48 | |
aoqi@0 | 49 | // deep copy of all XHandler contained in list |
aoqi@0 | 50 | XHandlers::XHandlers(XHandlers* other) : |
aoqi@0 | 51 | _list(other->length()) |
aoqi@0 | 52 | { |
aoqi@0 | 53 | for (int i = 0; i < other->length(); i++) { |
aoqi@0 | 54 | _list.append(new XHandler(other->handler_at(i))); |
aoqi@0 | 55 | } |
aoqi@0 | 56 | } |
aoqi@0 | 57 | |
aoqi@0 | 58 | // Returns whether a particular exception type can be caught. Also |
aoqi@0 | 59 | // returns true if klass is unloaded or any exception handler |
aoqi@0 | 60 | // classes are unloaded. type_is_exact indicates whether the throw |
aoqi@0 | 61 | // is known to be exactly that class or it might throw a subtype. |
aoqi@0 | 62 | bool XHandlers::could_catch(ciInstanceKlass* klass, bool type_is_exact) const { |
aoqi@0 | 63 | // the type is unknown so be conservative |
aoqi@0 | 64 | if (!klass->is_loaded()) { |
aoqi@0 | 65 | return true; |
aoqi@0 | 66 | } |
aoqi@0 | 67 | |
aoqi@0 | 68 | for (int i = 0; i < length(); i++) { |
aoqi@0 | 69 | XHandler* handler = handler_at(i); |
aoqi@0 | 70 | if (handler->is_catch_all()) { |
aoqi@0 | 71 | // catch of ANY |
aoqi@0 | 72 | return true; |
aoqi@0 | 73 | } |
aoqi@0 | 74 | ciInstanceKlass* handler_klass = handler->catch_klass(); |
aoqi@0 | 75 | // if it's unknown it might be catchable |
aoqi@0 | 76 | if (!handler_klass->is_loaded()) { |
aoqi@0 | 77 | return true; |
aoqi@0 | 78 | } |
aoqi@0 | 79 | // if the throw type is definitely a subtype of the catch type |
aoqi@0 | 80 | // then it can be caught. |
aoqi@0 | 81 | if (klass->is_subtype_of(handler_klass)) { |
aoqi@0 | 82 | return true; |
aoqi@0 | 83 | } |
aoqi@0 | 84 | if (!type_is_exact) { |
aoqi@0 | 85 | // If the type isn't exactly known then it can also be caught by |
aoqi@0 | 86 | // catch statements where the inexact type is a subtype of the |
aoqi@0 | 87 | // catch type. |
aoqi@0 | 88 | // given: foo extends bar extends Exception |
aoqi@0 | 89 | // throw bar can be caught by catch foo, catch bar, and catch |
aoqi@0 | 90 | // Exception, however it can't be caught by any handlers without |
aoqi@0 | 91 | // bar in its type hierarchy. |
aoqi@0 | 92 | if (handler_klass->is_subtype_of(klass)) { |
aoqi@0 | 93 | return true; |
aoqi@0 | 94 | } |
aoqi@0 | 95 | } |
aoqi@0 | 96 | } |
aoqi@0 | 97 | |
aoqi@0 | 98 | return false; |
aoqi@0 | 99 | } |
aoqi@0 | 100 | |
aoqi@0 | 101 | |
aoqi@0 | 102 | bool XHandlers::equals(XHandlers* others) const { |
aoqi@0 | 103 | if (others == NULL) return false; |
aoqi@0 | 104 | if (length() != others->length()) return false; |
aoqi@0 | 105 | |
aoqi@0 | 106 | for (int i = 0; i < length(); i++) { |
aoqi@0 | 107 | if (!handler_at(i)->equals(others->handler_at(i))) return false; |
aoqi@0 | 108 | } |
aoqi@0 | 109 | return true; |
aoqi@0 | 110 | } |
aoqi@0 | 111 | |
aoqi@0 | 112 | bool XHandler::equals(XHandler* other) const { |
aoqi@0 | 113 | assert(entry_pco() != -1 && other->entry_pco() != -1, "must have entry_pco"); |
aoqi@0 | 114 | |
aoqi@0 | 115 | if (entry_pco() != other->entry_pco()) return false; |
aoqi@0 | 116 | if (scope_count() != other->scope_count()) return false; |
aoqi@0 | 117 | if (_desc != other->_desc) return false; |
aoqi@0 | 118 | |
aoqi@0 | 119 | assert(entry_block() == other->entry_block(), "entry_block must be equal when entry_pco is equal"); |
aoqi@0 | 120 | return true; |
aoqi@0 | 121 | } |
aoqi@0 | 122 | |
aoqi@0 | 123 | |
aoqi@0 | 124 | // Implementation of IRScope |
aoqi@0 | 125 | BlockBegin* IRScope::build_graph(Compilation* compilation, int osr_bci) { |
aoqi@0 | 126 | GraphBuilder gm(compilation, this); |
aoqi@0 | 127 | NOT_PRODUCT(if (PrintValueNumbering && Verbose) gm.print_stats()); |
aoqi@0 | 128 | if (compilation->bailed_out()) return NULL; |
aoqi@0 | 129 | return gm.start(); |
aoqi@0 | 130 | } |
aoqi@0 | 131 | |
aoqi@0 | 132 | |
aoqi@0 | 133 | IRScope::IRScope(Compilation* compilation, IRScope* caller, int caller_bci, ciMethod* method, int osr_bci, bool create_graph) |
aoqi@0 | 134 | : _callees(2) |
aoqi@0 | 135 | , _compilation(compilation) |
aoqi@0 | 136 | , _requires_phi_function(method->max_locals()) |
aoqi@0 | 137 | { |
aoqi@0 | 138 | _caller = caller; |
aoqi@0 | 139 | _level = caller == NULL ? 0 : caller->level() + 1; |
aoqi@0 | 140 | _method = method; |
aoqi@0 | 141 | _xhandlers = new XHandlers(method); |
aoqi@0 | 142 | _number_of_locks = 0; |
aoqi@0 | 143 | _monitor_pairing_ok = method->has_balanced_monitors(); |
aoqi@0 | 144 | _wrote_final = false; |
aoqi@0 | 145 | _start = NULL; |
aoqi@0 | 146 | |
aoqi@0 | 147 | if (osr_bci == -1) { |
aoqi@0 | 148 | _requires_phi_function.clear(); |
aoqi@0 | 149 | } else { |
aoqi@0 | 150 | // selective creation of phi functions is not possibel in osr-methods |
aoqi@0 | 151 | _requires_phi_function.set_range(0, method->max_locals()); |
aoqi@0 | 152 | } |
aoqi@0 | 153 | |
aoqi@0 | 154 | assert(method->holder()->is_loaded() , "method holder must be loaded"); |
aoqi@0 | 155 | |
aoqi@0 | 156 | // build graph if monitor pairing is ok |
aoqi@0 | 157 | if (create_graph && monitor_pairing_ok()) _start = build_graph(compilation, osr_bci); |
aoqi@0 | 158 | } |
aoqi@0 | 159 | |
aoqi@0 | 160 | |
aoqi@0 | 161 | int IRScope::max_stack() const { |
aoqi@0 | 162 | int my_max = method()->max_stack(); |
aoqi@0 | 163 | int callee_max = 0; |
aoqi@0 | 164 | for (int i = 0; i < number_of_callees(); i++) { |
aoqi@0 | 165 | callee_max = MAX2(callee_max, callee_no(i)->max_stack()); |
aoqi@0 | 166 | } |
aoqi@0 | 167 | return my_max + callee_max; |
aoqi@0 | 168 | } |
aoqi@0 | 169 | |
aoqi@0 | 170 | |
aoqi@0 | 171 | bool IRScopeDebugInfo::should_reexecute() { |
aoqi@0 | 172 | ciMethod* cur_method = scope()->method(); |
aoqi@0 | 173 | int cur_bci = bci(); |
aoqi@0 | 174 | if (cur_method != NULL && cur_bci != SynchronizationEntryBCI) { |
aoqi@0 | 175 | Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci); |
aoqi@0 | 176 | return Interpreter::bytecode_should_reexecute(code); |
aoqi@0 | 177 | } else |
aoqi@0 | 178 | return false; |
aoqi@0 | 179 | } |
aoqi@0 | 180 | |
aoqi@0 | 181 | |
aoqi@0 | 182 | // Implementation of CodeEmitInfo |
aoqi@0 | 183 | |
aoqi@0 | 184 | // Stack must be NON-null |
aoqi@0 | 185 | CodeEmitInfo::CodeEmitInfo(ValueStack* stack, XHandlers* exception_handlers, bool deoptimize_on_exception) |
aoqi@0 | 186 | : _scope(stack->scope()) |
aoqi@0 | 187 | , _scope_debug_info(NULL) |
aoqi@0 | 188 | , _oop_map(NULL) |
aoqi@0 | 189 | , _stack(stack) |
aoqi@0 | 190 | , _exception_handlers(exception_handlers) |
aoqi@0 | 191 | , _is_method_handle_invoke(false) |
aoqi@0 | 192 | , _deoptimize_on_exception(deoptimize_on_exception) { |
aoqi@0 | 193 | assert(_stack != NULL, "must be non null"); |
aoqi@0 | 194 | } |
aoqi@0 | 195 | |
aoqi@0 | 196 | |
aoqi@0 | 197 | CodeEmitInfo::CodeEmitInfo(CodeEmitInfo* info, ValueStack* stack) |
aoqi@0 | 198 | : _scope(info->_scope) |
aoqi@0 | 199 | , _exception_handlers(NULL) |
aoqi@0 | 200 | , _scope_debug_info(NULL) |
aoqi@0 | 201 | , _oop_map(NULL) |
aoqi@0 | 202 | , _stack(stack == NULL ? info->_stack : stack) |
aoqi@0 | 203 | , _is_method_handle_invoke(info->_is_method_handle_invoke) |
aoqi@0 | 204 | , _deoptimize_on_exception(info->_deoptimize_on_exception) { |
aoqi@0 | 205 | |
aoqi@0 | 206 | // deep copy of exception handlers |
aoqi@0 | 207 | if (info->_exception_handlers != NULL) { |
aoqi@0 | 208 | _exception_handlers = new XHandlers(info->_exception_handlers); |
aoqi@0 | 209 | } |
aoqi@0 | 210 | } |
aoqi@0 | 211 | |
aoqi@0 | 212 | |
aoqi@0 | 213 | void CodeEmitInfo::record_debug_info(DebugInformationRecorder* recorder, int pc_offset) { |
aoqi@0 | 214 | // record the safepoint before recording the debug info for enclosing scopes |
aoqi@0 | 215 | recorder->add_safepoint(pc_offset, _oop_map->deep_copy()); |
aoqi@0 | 216 | _scope_debug_info->record_debug_info(recorder, pc_offset, true/*topmost*/, _is_method_handle_invoke); |
aoqi@0 | 217 | recorder->end_safepoint(pc_offset); |
aoqi@0 | 218 | } |
aoqi@0 | 219 | |
aoqi@0 | 220 | |
aoqi@0 | 221 | void CodeEmitInfo::add_register_oop(LIR_Opr opr) { |
aoqi@0 | 222 | assert(_oop_map != NULL, "oop map must already exist"); |
aoqi@0 | 223 | assert(opr->is_single_cpu(), "should not call otherwise"); |
aoqi@0 | 224 | |
aoqi@0 | 225 | VMReg name = frame_map()->regname(opr); |
aoqi@0 | 226 | _oop_map->set_oop(name); |
aoqi@0 | 227 | } |
aoqi@0 | 228 | |
aoqi@0 | 229 | // Mirror the stack size calculation in the deopt code |
aoqi@0 | 230 | // How much stack space would we need at this point in the program in |
aoqi@0 | 231 | // case of deoptimization? |
aoqi@0 | 232 | int CodeEmitInfo::interpreter_frame_size() const { |
aoqi@0 | 233 | ValueStack* state = _stack; |
aoqi@0 | 234 | int size = 0; |
aoqi@0 | 235 | int callee_parameters = 0; |
aoqi@0 | 236 | int callee_locals = 0; |
aoqi@0 | 237 | int extra_args = state->scope()->method()->max_stack() - state->stack_size(); |
aoqi@0 | 238 | |
aoqi@0 | 239 | while (state != NULL) { |
aoqi@0 | 240 | int locks = state->locks_size(); |
aoqi@0 | 241 | int temps = state->stack_size(); |
aoqi@0 | 242 | bool is_top_frame = (state == _stack); |
aoqi@0 | 243 | ciMethod* method = state->scope()->method(); |
aoqi@0 | 244 | |
aoqi@0 | 245 | int frame_size = BytesPerWord * Interpreter::size_activation(method->max_stack(), |
aoqi@0 | 246 | temps + callee_parameters, |
aoqi@0 | 247 | extra_args, |
aoqi@0 | 248 | locks, |
aoqi@0 | 249 | callee_parameters, |
aoqi@0 | 250 | callee_locals, |
aoqi@0 | 251 | is_top_frame); |
aoqi@0 | 252 | size += frame_size; |
aoqi@0 | 253 | |
aoqi@0 | 254 | callee_parameters = method->size_of_parameters(); |
aoqi@0 | 255 | callee_locals = method->max_locals(); |
aoqi@0 | 256 | extra_args = 0; |
aoqi@0 | 257 | state = state->caller_state(); |
aoqi@0 | 258 | } |
aoqi@0 | 259 | return size + Deoptimization::last_frame_adjust(0, callee_locals) * BytesPerWord; |
aoqi@0 | 260 | } |
aoqi@0 | 261 | |
aoqi@0 | 262 | // Implementation of IR |
aoqi@0 | 263 | |
aoqi@0 | 264 | IR::IR(Compilation* compilation, ciMethod* method, int osr_bci) : |
aoqi@0 | 265 | _locals_size(in_WordSize(-1)) |
aoqi@0 | 266 | , _num_loops(0) { |
aoqi@0 | 267 | // setup IR fields |
aoqi@0 | 268 | _compilation = compilation; |
aoqi@0 | 269 | _top_scope = new IRScope(compilation, NULL, -1, method, osr_bci, true); |
aoqi@0 | 270 | _code = NULL; |
aoqi@0 | 271 | } |
aoqi@0 | 272 | |
aoqi@0 | 273 | |
aoqi@0 | 274 | void IR::optimize_blocks() { |
aoqi@0 | 275 | Optimizer opt(this); |
aoqi@0 | 276 | if (!compilation()->profile_branches()) { |
aoqi@0 | 277 | if (DoCEE) { |
aoqi@0 | 278 | opt.eliminate_conditional_expressions(); |
aoqi@0 | 279 | #ifndef PRODUCT |
aoqi@0 | 280 | if (PrintCFG || PrintCFG1) { tty->print_cr("CFG after CEE"); print(true); } |
aoqi@0 | 281 | if (PrintIR || PrintIR1 ) { tty->print_cr("IR after CEE"); print(false); } |
aoqi@0 | 282 | #endif |
aoqi@0 | 283 | } |
aoqi@0 | 284 | if (EliminateBlocks) { |
aoqi@0 | 285 | opt.eliminate_blocks(); |
aoqi@0 | 286 | #ifndef PRODUCT |
aoqi@0 | 287 | if (PrintCFG || PrintCFG1) { tty->print_cr("CFG after block elimination"); print(true); } |
aoqi@0 | 288 | if (PrintIR || PrintIR1 ) { tty->print_cr("IR after block elimination"); print(false); } |
aoqi@0 | 289 | #endif |
aoqi@0 | 290 | } |
aoqi@0 | 291 | } |
aoqi@0 | 292 | } |
aoqi@0 | 293 | |
aoqi@0 | 294 | void IR::eliminate_null_checks() { |
aoqi@0 | 295 | Optimizer opt(this); |
aoqi@0 | 296 | if (EliminateNullChecks) { |
aoqi@0 | 297 | opt.eliminate_null_checks(); |
aoqi@0 | 298 | #ifndef PRODUCT |
aoqi@0 | 299 | if (PrintCFG || PrintCFG1) { tty->print_cr("CFG after null check elimination"); print(true); } |
aoqi@0 | 300 | if (PrintIR || PrintIR1 ) { tty->print_cr("IR after null check elimination"); print(false); } |
aoqi@0 | 301 | #endif |
aoqi@0 | 302 | } |
aoqi@0 | 303 | } |
aoqi@0 | 304 | |
aoqi@0 | 305 | |
aoqi@0 | 306 | static int sort_pairs(BlockPair** a, BlockPair** b) { |
aoqi@0 | 307 | if ((*a)->from() == (*b)->from()) { |
aoqi@0 | 308 | return (*a)->to()->block_id() - (*b)->to()->block_id(); |
aoqi@0 | 309 | } else { |
aoqi@0 | 310 | return (*a)->from()->block_id() - (*b)->from()->block_id(); |
aoqi@0 | 311 | } |
aoqi@0 | 312 | } |
aoqi@0 | 313 | |
aoqi@0 | 314 | |
aoqi@0 | 315 | class CriticalEdgeFinder: public BlockClosure { |
aoqi@0 | 316 | BlockPairList blocks; |
aoqi@0 | 317 | IR* _ir; |
aoqi@0 | 318 | |
aoqi@0 | 319 | public: |
aoqi@0 | 320 | CriticalEdgeFinder(IR* ir): _ir(ir) {} |
aoqi@0 | 321 | void block_do(BlockBegin* bb) { |
aoqi@0 | 322 | BlockEnd* be = bb->end(); |
aoqi@0 | 323 | int nos = be->number_of_sux(); |
aoqi@0 | 324 | if (nos >= 2) { |
aoqi@0 | 325 | for (int i = 0; i < nos; i++) { |
aoqi@0 | 326 | BlockBegin* sux = be->sux_at(i); |
aoqi@0 | 327 | if (sux->number_of_preds() >= 2) { |
aoqi@0 | 328 | blocks.append(new BlockPair(bb, sux)); |
aoqi@0 | 329 | } |
aoqi@0 | 330 | } |
aoqi@0 | 331 | } |
aoqi@0 | 332 | } |
aoqi@0 | 333 | |
aoqi@0 | 334 | void split_edges() { |
aoqi@0 | 335 | BlockPair* last_pair = NULL; |
aoqi@0 | 336 | blocks.sort(sort_pairs); |
aoqi@0 | 337 | for (int i = 0; i < blocks.length(); i++) { |
aoqi@0 | 338 | BlockPair* pair = blocks.at(i); |
aoqi@0 | 339 | if (last_pair != NULL && pair->is_same(last_pair)) continue; |
aoqi@0 | 340 | BlockBegin* from = pair->from(); |
aoqi@0 | 341 | BlockBegin* to = pair->to(); |
aoqi@0 | 342 | BlockBegin* split = from->insert_block_between(to); |
aoqi@0 | 343 | #ifndef PRODUCT |
aoqi@0 | 344 | if ((PrintIR || PrintIR1) && Verbose) { |
aoqi@0 | 345 | tty->print_cr("Split critical edge B%d -> B%d (new block B%d)", |
aoqi@0 | 346 | from->block_id(), to->block_id(), split->block_id()); |
aoqi@0 | 347 | } |
aoqi@0 | 348 | #endif |
aoqi@0 | 349 | last_pair = pair; |
aoqi@0 | 350 | } |
aoqi@0 | 351 | } |
aoqi@0 | 352 | }; |
aoqi@0 | 353 | |
aoqi@0 | 354 | void IR::split_critical_edges() { |
aoqi@0 | 355 | CriticalEdgeFinder cef(this); |
aoqi@0 | 356 | |
aoqi@0 | 357 | iterate_preorder(&cef); |
aoqi@0 | 358 | cef.split_edges(); |
aoqi@0 | 359 | } |
aoqi@0 | 360 | |
aoqi@0 | 361 | |
aoqi@0 | 362 | class UseCountComputer: public ValueVisitor, BlockClosure { |
aoqi@0 | 363 | private: |
aoqi@0 | 364 | void visit(Value* n) { |
aoqi@0 | 365 | // Local instructions and Phis for expression stack values at the |
aoqi@0 | 366 | // start of basic blocks are not added to the instruction list |
aoqi@0 | 367 | if (!(*n)->is_linked() && (*n)->can_be_linked()) { |
aoqi@0 | 368 | assert(false, "a node was not appended to the graph"); |
aoqi@0 | 369 | Compilation::current()->bailout("a node was not appended to the graph"); |
aoqi@0 | 370 | } |
aoqi@0 | 371 | // use n's input if not visited before |
aoqi@0 | 372 | if (!(*n)->is_pinned() && !(*n)->has_uses()) { |
aoqi@0 | 373 | // note: a) if the instruction is pinned, it will be handled by compute_use_count |
aoqi@0 | 374 | // b) if the instruction has uses, it was touched before |
aoqi@0 | 375 | // => in both cases we don't need to update n's values |
aoqi@0 | 376 | uses_do(n); |
aoqi@0 | 377 | } |
aoqi@0 | 378 | // use n |
aoqi@0 | 379 | (*n)->_use_count++; |
aoqi@0 | 380 | } |
aoqi@0 | 381 | |
aoqi@0 | 382 | Values* worklist; |
aoqi@0 | 383 | int depth; |
aoqi@0 | 384 | enum { |
aoqi@0 | 385 | max_recurse_depth = 20 |
aoqi@0 | 386 | }; |
aoqi@0 | 387 | |
aoqi@0 | 388 | void uses_do(Value* n) { |
aoqi@0 | 389 | depth++; |
aoqi@0 | 390 | if (depth > max_recurse_depth) { |
aoqi@0 | 391 | // don't allow the traversal to recurse too deeply |
aoqi@0 | 392 | worklist->push(*n); |
aoqi@0 | 393 | } else { |
aoqi@0 | 394 | (*n)->input_values_do(this); |
aoqi@0 | 395 | // special handling for some instructions |
aoqi@0 | 396 | if ((*n)->as_BlockEnd() != NULL) { |
aoqi@0 | 397 | // note on BlockEnd: |
aoqi@0 | 398 | // must 'use' the stack only if the method doesn't |
aoqi@0 | 399 | // terminate, however, in those cases stack is empty |
aoqi@0 | 400 | (*n)->state_values_do(this); |
aoqi@0 | 401 | } |
aoqi@0 | 402 | } |
aoqi@0 | 403 | depth--; |
aoqi@0 | 404 | } |
aoqi@0 | 405 | |
aoqi@0 | 406 | void block_do(BlockBegin* b) { |
aoqi@0 | 407 | depth = 0; |
aoqi@0 | 408 | // process all pinned nodes as the roots of expression trees |
aoqi@0 | 409 | for (Instruction* n = b; n != NULL; n = n->next()) { |
aoqi@0 | 410 | if (n->is_pinned()) uses_do(&n); |
aoqi@0 | 411 | } |
aoqi@0 | 412 | assert(depth == 0, "should have counted back down"); |
aoqi@0 | 413 | |
aoqi@0 | 414 | // now process any unpinned nodes which recursed too deeply |
aoqi@0 | 415 | while (worklist->length() > 0) { |
aoqi@0 | 416 | Value t = worklist->pop(); |
aoqi@0 | 417 | if (!t->is_pinned()) { |
aoqi@0 | 418 | // compute the use count |
aoqi@0 | 419 | uses_do(&t); |
aoqi@0 | 420 | |
aoqi@0 | 421 | // pin the instruction so that LIRGenerator doesn't recurse |
aoqi@0 | 422 | // too deeply during it's evaluation. |
aoqi@0 | 423 | t->pin(); |
aoqi@0 | 424 | } |
aoqi@0 | 425 | } |
aoqi@0 | 426 | assert(depth == 0, "should have counted back down"); |
aoqi@0 | 427 | } |
aoqi@0 | 428 | |
aoqi@0 | 429 | UseCountComputer() { |
aoqi@0 | 430 | worklist = new Values(); |
aoqi@0 | 431 | depth = 0; |
aoqi@0 | 432 | } |
aoqi@0 | 433 | |
aoqi@0 | 434 | public: |
aoqi@0 | 435 | static void compute(BlockList* blocks) { |
aoqi@0 | 436 | UseCountComputer ucc; |
aoqi@0 | 437 | blocks->iterate_backward(&ucc); |
aoqi@0 | 438 | } |
aoqi@0 | 439 | }; |
aoqi@0 | 440 | |
aoqi@0 | 441 | |
aoqi@0 | 442 | // helper macro for short definition of trace-output inside code |
aoqi@0 | 443 | #ifndef PRODUCT |
aoqi@0 | 444 | #define TRACE_LINEAR_SCAN(level, code) \ |
aoqi@0 | 445 | if (TraceLinearScanLevel >= level) { \ |
aoqi@0 | 446 | code; \ |
aoqi@0 | 447 | } |
aoqi@0 | 448 | #else |
aoqi@0 | 449 | #define TRACE_LINEAR_SCAN(level, code) |
aoqi@0 | 450 | #endif |
aoqi@0 | 451 | |
aoqi@0 | 452 | class ComputeLinearScanOrder : public StackObj { |
aoqi@0 | 453 | private: |
aoqi@0 | 454 | int _max_block_id; // the highest block_id of a block |
aoqi@0 | 455 | int _num_blocks; // total number of blocks (smaller than _max_block_id) |
aoqi@0 | 456 | int _num_loops; // total number of loops |
aoqi@0 | 457 | bool _iterative_dominators;// method requires iterative computation of dominatiors |
aoqi@0 | 458 | |
aoqi@0 | 459 | BlockList* _linear_scan_order; // the resulting list of blocks in correct order |
aoqi@0 | 460 | |
aoqi@0 | 461 | BitMap _visited_blocks; // used for recursive processing of blocks |
aoqi@0 | 462 | BitMap _active_blocks; // used for recursive processing of blocks |
aoqi@0 | 463 | BitMap _dominator_blocks; // temproary BitMap used for computation of dominator |
aoqi@0 | 464 | intArray _forward_branches; // number of incoming forward branches for each block |
aoqi@0 | 465 | BlockList _loop_end_blocks; // list of all loop end blocks collected during count_edges |
aoqi@0 | 466 | BitMap2D _loop_map; // two-dimensional bit set: a bit is set if a block is contained in a loop |
aoqi@0 | 467 | BlockList _work_list; // temporary list (used in mark_loops and compute_order) |
aoqi@0 | 468 | BlockList _loop_headers; |
aoqi@0 | 469 | |
aoqi@0 | 470 | Compilation* _compilation; |
aoqi@0 | 471 | |
aoqi@0 | 472 | // accessors for _visited_blocks and _active_blocks |
aoqi@0 | 473 | void init_visited() { _active_blocks.clear(); _visited_blocks.clear(); } |
aoqi@0 | 474 | bool is_visited(BlockBegin* b) const { return _visited_blocks.at(b->block_id()); } |
aoqi@0 | 475 | bool is_active(BlockBegin* b) const { return _active_blocks.at(b->block_id()); } |
aoqi@0 | 476 | void set_visited(BlockBegin* b) { assert(!is_visited(b), "already set"); _visited_blocks.set_bit(b->block_id()); } |
aoqi@0 | 477 | void set_active(BlockBegin* b) { assert(!is_active(b), "already set"); _active_blocks.set_bit(b->block_id()); } |
aoqi@0 | 478 | void clear_active(BlockBegin* b) { assert(is_active(b), "not already"); _active_blocks.clear_bit(b->block_id()); } |
aoqi@0 | 479 | |
aoqi@0 | 480 | // accessors for _forward_branches |
aoqi@0 | 481 | void inc_forward_branches(BlockBegin* b) { _forward_branches.at_put(b->block_id(), _forward_branches.at(b->block_id()) + 1); } |
aoqi@0 | 482 | int dec_forward_branches(BlockBegin* b) { _forward_branches.at_put(b->block_id(), _forward_branches.at(b->block_id()) - 1); return _forward_branches.at(b->block_id()); } |
aoqi@0 | 483 | |
aoqi@0 | 484 | // accessors for _loop_map |
aoqi@0 | 485 | bool is_block_in_loop (int loop_idx, BlockBegin* b) const { return _loop_map.at(loop_idx, b->block_id()); } |
aoqi@0 | 486 | void set_block_in_loop (int loop_idx, BlockBegin* b) { _loop_map.set_bit(loop_idx, b->block_id()); } |
aoqi@0 | 487 | void clear_block_in_loop(int loop_idx, int block_id) { _loop_map.clear_bit(loop_idx, block_id); } |
aoqi@0 | 488 | |
aoqi@0 | 489 | // count edges between blocks |
aoqi@0 | 490 | void count_edges(BlockBegin* cur, BlockBegin* parent); |
aoqi@0 | 491 | |
aoqi@0 | 492 | // loop detection |
aoqi@0 | 493 | void mark_loops(); |
aoqi@0 | 494 | void clear_non_natural_loops(BlockBegin* start_block); |
aoqi@0 | 495 | void assign_loop_depth(BlockBegin* start_block); |
aoqi@0 | 496 | |
aoqi@0 | 497 | // computation of final block order |
aoqi@0 | 498 | BlockBegin* common_dominator(BlockBegin* a, BlockBegin* b); |
aoqi@0 | 499 | void compute_dominator(BlockBegin* cur, BlockBegin* parent); |
aoqi@0 | 500 | int compute_weight(BlockBegin* cur); |
aoqi@0 | 501 | bool ready_for_processing(BlockBegin* cur); |
aoqi@0 | 502 | void sort_into_work_list(BlockBegin* b); |
aoqi@0 | 503 | void append_block(BlockBegin* cur); |
aoqi@0 | 504 | void compute_order(BlockBegin* start_block); |
aoqi@0 | 505 | |
aoqi@0 | 506 | // fixup of dominators for non-natural loops |
aoqi@0 | 507 | bool compute_dominators_iter(); |
aoqi@0 | 508 | void compute_dominators(); |
aoqi@0 | 509 | |
aoqi@0 | 510 | // debug functions |
aoqi@0 | 511 | NOT_PRODUCT(void print_blocks();) |
aoqi@0 | 512 | DEBUG_ONLY(void verify();) |
aoqi@0 | 513 | |
aoqi@0 | 514 | Compilation* compilation() const { return _compilation; } |
aoqi@0 | 515 | public: |
aoqi@0 | 516 | ComputeLinearScanOrder(Compilation* c, BlockBegin* start_block); |
aoqi@0 | 517 | |
aoqi@0 | 518 | // accessors for final result |
aoqi@0 | 519 | BlockList* linear_scan_order() const { return _linear_scan_order; } |
aoqi@0 | 520 | int num_loops() const { return _num_loops; } |
aoqi@0 | 521 | }; |
aoqi@0 | 522 | |
aoqi@0 | 523 | |
aoqi@0 | 524 | ComputeLinearScanOrder::ComputeLinearScanOrder(Compilation* c, BlockBegin* start_block) : |
aoqi@0 | 525 | _max_block_id(BlockBegin::number_of_blocks()), |
aoqi@0 | 526 | _num_blocks(0), |
aoqi@0 | 527 | _num_loops(0), |
aoqi@0 | 528 | _iterative_dominators(false), |
aoqi@0 | 529 | _visited_blocks(_max_block_id), |
aoqi@0 | 530 | _active_blocks(_max_block_id), |
aoqi@0 | 531 | _dominator_blocks(_max_block_id), |
aoqi@0 | 532 | _forward_branches(_max_block_id, 0), |
aoqi@0 | 533 | _loop_end_blocks(8), |
aoqi@0 | 534 | _work_list(8), |
aoqi@0 | 535 | _linear_scan_order(NULL), // initialized later with correct size |
aoqi@0 | 536 | _loop_map(0, 0), // initialized later with correct size |
aoqi@0 | 537 | _compilation(c) |
aoqi@0 | 538 | { |
aoqi@0 | 539 | TRACE_LINEAR_SCAN(2, tty->print_cr("***** computing linear-scan block order")); |
aoqi@0 | 540 | |
aoqi@0 | 541 | init_visited(); |
aoqi@0 | 542 | count_edges(start_block, NULL); |
aoqi@0 | 543 | |
aoqi@0 | 544 | if (compilation()->is_profiling()) { |
aoqi@0 | 545 | ciMethod *method = compilation()->method(); |
aoqi@0 | 546 | if (!method->is_accessor()) { |
aoqi@0 | 547 | ciMethodData* md = method->method_data_or_null(); |
aoqi@0 | 548 | assert(md != NULL, "Sanity"); |
aoqi@0 | 549 | md->set_compilation_stats(_num_loops, _num_blocks); |
aoqi@0 | 550 | } |
aoqi@0 | 551 | } |
aoqi@0 | 552 | |
aoqi@0 | 553 | if (_num_loops > 0) { |
aoqi@0 | 554 | mark_loops(); |
aoqi@0 | 555 | clear_non_natural_loops(start_block); |
aoqi@0 | 556 | assign_loop_depth(start_block); |
aoqi@0 | 557 | } |
aoqi@0 | 558 | |
aoqi@0 | 559 | compute_order(start_block); |
aoqi@0 | 560 | compute_dominators(); |
aoqi@0 | 561 | |
aoqi@0 | 562 | NOT_PRODUCT(print_blocks()); |
aoqi@0 | 563 | DEBUG_ONLY(verify()); |
aoqi@0 | 564 | } |
aoqi@0 | 565 | |
aoqi@0 | 566 | |
aoqi@0 | 567 | // Traverse the CFG: |
aoqi@0 | 568 | // * count total number of blocks |
aoqi@0 | 569 | // * count all incoming edges and backward incoming edges |
aoqi@0 | 570 | // * number loop header blocks |
aoqi@0 | 571 | // * create a list with all loop end blocks |
aoqi@0 | 572 | void ComputeLinearScanOrder::count_edges(BlockBegin* cur, BlockBegin* parent) { |
aoqi@0 | 573 | TRACE_LINEAR_SCAN(3, tty->print_cr("Enter count_edges for block B%d coming from B%d", cur->block_id(), parent != NULL ? parent->block_id() : -1)); |
aoqi@0 | 574 | assert(cur->dominator() == NULL, "dominator already initialized"); |
aoqi@0 | 575 | |
aoqi@0 | 576 | if (is_active(cur)) { |
aoqi@0 | 577 | TRACE_LINEAR_SCAN(3, tty->print_cr("backward branch")); |
aoqi@0 | 578 | assert(is_visited(cur), "block must be visisted when block is active"); |
aoqi@0 | 579 | assert(parent != NULL, "must have parent"); |
aoqi@0 | 580 | |
aoqi@0 | 581 | cur->set(BlockBegin::linear_scan_loop_header_flag); |
aoqi@0 | 582 | cur->set(BlockBegin::backward_branch_target_flag); |
aoqi@0 | 583 | |
aoqi@0 | 584 | parent->set(BlockBegin::linear_scan_loop_end_flag); |
aoqi@0 | 585 | |
aoqi@0 | 586 | // When a loop header is also the start of an exception handler, then the backward branch is |
aoqi@0 | 587 | // an exception edge. Because such edges are usually critical edges which cannot be split, the |
aoqi@0 | 588 | // loop must be excluded here from processing. |
aoqi@0 | 589 | if (cur->is_set(BlockBegin::exception_entry_flag)) { |
aoqi@0 | 590 | // Make sure that dominators are correct in this weird situation |
aoqi@0 | 591 | _iterative_dominators = true; |
aoqi@0 | 592 | return; |
aoqi@0 | 593 | } |
aoqi@0 | 594 | assert(parent->number_of_sux() == 1 && parent->sux_at(0) == cur, |
aoqi@0 | 595 | "loop end blocks must have one successor (critical edges are split)"); |
aoqi@0 | 596 | |
aoqi@0 | 597 | _loop_end_blocks.append(parent); |
aoqi@0 | 598 | return; |
aoqi@0 | 599 | } |
aoqi@0 | 600 | |
aoqi@0 | 601 | // increment number of incoming forward branches |
aoqi@0 | 602 | inc_forward_branches(cur); |
aoqi@0 | 603 | |
aoqi@0 | 604 | if (is_visited(cur)) { |
aoqi@0 | 605 | TRACE_LINEAR_SCAN(3, tty->print_cr("block already visited")); |
aoqi@0 | 606 | return; |
aoqi@0 | 607 | } |
aoqi@0 | 608 | |
aoqi@0 | 609 | _num_blocks++; |
aoqi@0 | 610 | set_visited(cur); |
aoqi@0 | 611 | set_active(cur); |
aoqi@0 | 612 | |
aoqi@0 | 613 | // recursive call for all successors |
aoqi@0 | 614 | int i; |
aoqi@0 | 615 | for (i = cur->number_of_sux() - 1; i >= 0; i--) { |
aoqi@0 | 616 | count_edges(cur->sux_at(i), cur); |
aoqi@0 | 617 | } |
aoqi@0 | 618 | for (i = cur->number_of_exception_handlers() - 1; i >= 0; i--) { |
aoqi@0 | 619 | count_edges(cur->exception_handler_at(i), cur); |
aoqi@0 | 620 | } |
aoqi@0 | 621 | |
aoqi@0 | 622 | clear_active(cur); |
aoqi@0 | 623 | |
aoqi@0 | 624 | // Each loop has a unique number. |
aoqi@0 | 625 | // When multiple loops are nested, assign_loop_depth assumes that the |
aoqi@0 | 626 | // innermost loop has the lowest number. This is guaranteed by setting |
aoqi@0 | 627 | // the loop number after the recursive calls for the successors above |
aoqi@0 | 628 | // have returned. |
aoqi@0 | 629 | if (cur->is_set(BlockBegin::linear_scan_loop_header_flag)) { |
aoqi@0 | 630 | assert(cur->loop_index() == -1, "cannot set loop-index twice"); |
aoqi@0 | 631 | TRACE_LINEAR_SCAN(3, tty->print_cr("Block B%d is loop header of loop %d", cur->block_id(), _num_loops)); |
aoqi@0 | 632 | |
aoqi@0 | 633 | cur->set_loop_index(_num_loops); |
aoqi@0 | 634 | _loop_headers.append(cur); |
aoqi@0 | 635 | _num_loops++; |
aoqi@0 | 636 | } |
aoqi@0 | 637 | |
aoqi@0 | 638 | TRACE_LINEAR_SCAN(3, tty->print_cr("Finished count_edges for block B%d", cur->block_id())); |
aoqi@0 | 639 | } |
aoqi@0 | 640 | |
aoqi@0 | 641 | |
aoqi@0 | 642 | void ComputeLinearScanOrder::mark_loops() { |
aoqi@0 | 643 | TRACE_LINEAR_SCAN(3, tty->print_cr("----- marking loops")); |
aoqi@0 | 644 | |
aoqi@0 | 645 | _loop_map = BitMap2D(_num_loops, _max_block_id); |
aoqi@0 | 646 | _loop_map.clear(); |
aoqi@0 | 647 | |
aoqi@0 | 648 | for (int i = _loop_end_blocks.length() - 1; i >= 0; i--) { |
aoqi@0 | 649 | BlockBegin* loop_end = _loop_end_blocks.at(i); |
aoqi@0 | 650 | BlockBegin* loop_start = loop_end->sux_at(0); |
aoqi@0 | 651 | int loop_idx = loop_start->loop_index(); |
aoqi@0 | 652 | |
aoqi@0 | 653 | TRACE_LINEAR_SCAN(3, tty->print_cr("Processing loop from B%d to B%d (loop %d):", loop_start->block_id(), loop_end->block_id(), loop_idx)); |
aoqi@0 | 654 | assert(loop_end->is_set(BlockBegin::linear_scan_loop_end_flag), "loop end flag must be set"); |
aoqi@0 | 655 | assert(loop_end->number_of_sux() == 1, "incorrect number of successors"); |
aoqi@0 | 656 | assert(loop_start->is_set(BlockBegin::linear_scan_loop_header_flag), "loop header flag must be set"); |
aoqi@0 | 657 | assert(loop_idx >= 0 && loop_idx < _num_loops, "loop index not set"); |
aoqi@0 | 658 | assert(_work_list.is_empty(), "work list must be empty before processing"); |
aoqi@0 | 659 | |
aoqi@0 | 660 | // add the end-block of the loop to the working list |
aoqi@0 | 661 | _work_list.push(loop_end); |
aoqi@0 | 662 | set_block_in_loop(loop_idx, loop_end); |
aoqi@0 | 663 | do { |
aoqi@0 | 664 | BlockBegin* cur = _work_list.pop(); |
aoqi@0 | 665 | |
aoqi@0 | 666 | TRACE_LINEAR_SCAN(3, tty->print_cr(" processing B%d", cur->block_id())); |
aoqi@0 | 667 | assert(is_block_in_loop(loop_idx, cur), "bit in loop map must be set when block is in work list"); |
aoqi@0 | 668 | |
aoqi@0 | 669 | // recursive processing of all predecessors ends when start block of loop is reached |
aoqi@0 | 670 | if (cur != loop_start && !cur->is_set(BlockBegin::osr_entry_flag)) { |
aoqi@0 | 671 | for (int j = cur->number_of_preds() - 1; j >= 0; j--) { |
aoqi@0 | 672 | BlockBegin* pred = cur->pred_at(j); |
aoqi@0 | 673 | |
aoqi@0 | 674 | if (!is_block_in_loop(loop_idx, pred) /*&& !pred->is_set(BlockBeginosr_entry_flag)*/) { |
aoqi@0 | 675 | // this predecessor has not been processed yet, so add it to work list |
aoqi@0 | 676 | TRACE_LINEAR_SCAN(3, tty->print_cr(" pushing B%d", pred->block_id())); |
aoqi@0 | 677 | _work_list.push(pred); |
aoqi@0 | 678 | set_block_in_loop(loop_idx, pred); |
aoqi@0 | 679 | } |
aoqi@0 | 680 | } |
aoqi@0 | 681 | } |
aoqi@0 | 682 | } while (!_work_list.is_empty()); |
aoqi@0 | 683 | } |
aoqi@0 | 684 | } |
aoqi@0 | 685 | |
aoqi@0 | 686 | |
aoqi@0 | 687 | // check for non-natural loops (loops where the loop header does not dominate |
aoqi@0 | 688 | // all other loop blocks = loops with mulitple entries). |
aoqi@0 | 689 | // such loops are ignored |
aoqi@0 | 690 | void ComputeLinearScanOrder::clear_non_natural_loops(BlockBegin* start_block) { |
aoqi@0 | 691 | for (int i = _num_loops - 1; i >= 0; i--) { |
aoqi@0 | 692 | if (is_block_in_loop(i, start_block)) { |
aoqi@0 | 693 | // loop i contains the entry block of the method |
aoqi@0 | 694 | // -> this is not a natural loop, so ignore it |
aoqi@0 | 695 | TRACE_LINEAR_SCAN(2, tty->print_cr("Loop %d is non-natural, so it is ignored", i)); |
aoqi@0 | 696 | |
aoqi@0 | 697 | BlockBegin *loop_header = _loop_headers.at(i); |
aoqi@0 | 698 | assert(loop_header->is_set(BlockBegin::linear_scan_loop_header_flag), "Must be loop header"); |
aoqi@0 | 699 | |
aoqi@0 | 700 | for (int j = 0; j < loop_header->number_of_preds(); j++) { |
aoqi@0 | 701 | BlockBegin *pred = loop_header->pred_at(j); |
aoqi@0 | 702 | pred->clear(BlockBegin::linear_scan_loop_end_flag); |
aoqi@0 | 703 | } |
aoqi@0 | 704 | |
aoqi@0 | 705 | loop_header->clear(BlockBegin::linear_scan_loop_header_flag); |
aoqi@0 | 706 | |
aoqi@0 | 707 | for (int block_id = _max_block_id - 1; block_id >= 0; block_id--) { |
aoqi@0 | 708 | clear_block_in_loop(i, block_id); |
aoqi@0 | 709 | } |
aoqi@0 | 710 | _iterative_dominators = true; |
aoqi@0 | 711 | } |
aoqi@0 | 712 | } |
aoqi@0 | 713 | } |
aoqi@0 | 714 | |
aoqi@0 | 715 | void ComputeLinearScanOrder::assign_loop_depth(BlockBegin* start_block) { |
aoqi@0 | 716 | TRACE_LINEAR_SCAN(3, tty->print_cr("----- computing loop-depth and weight")); |
aoqi@0 | 717 | init_visited(); |
aoqi@0 | 718 | |
aoqi@0 | 719 | assert(_work_list.is_empty(), "work list must be empty before processing"); |
aoqi@0 | 720 | _work_list.append(start_block); |
aoqi@0 | 721 | |
aoqi@0 | 722 | do { |
aoqi@0 | 723 | BlockBegin* cur = _work_list.pop(); |
aoqi@0 | 724 | |
aoqi@0 | 725 | if (!is_visited(cur)) { |
aoqi@0 | 726 | set_visited(cur); |
aoqi@0 | 727 | TRACE_LINEAR_SCAN(4, tty->print_cr("Computing loop depth for block B%d", cur->block_id())); |
aoqi@0 | 728 | |
aoqi@0 | 729 | // compute loop-depth and loop-index for the block |
aoqi@0 | 730 | assert(cur->loop_depth() == 0, "cannot set loop-depth twice"); |
aoqi@0 | 731 | int i; |
aoqi@0 | 732 | int loop_depth = 0; |
aoqi@0 | 733 | int min_loop_idx = -1; |
aoqi@0 | 734 | for (i = _num_loops - 1; i >= 0; i--) { |
aoqi@0 | 735 | if (is_block_in_loop(i, cur)) { |
aoqi@0 | 736 | loop_depth++; |
aoqi@0 | 737 | min_loop_idx = i; |
aoqi@0 | 738 | } |
aoqi@0 | 739 | } |
aoqi@0 | 740 | cur->set_loop_depth(loop_depth); |
aoqi@0 | 741 | cur->set_loop_index(min_loop_idx); |
aoqi@0 | 742 | |
aoqi@0 | 743 | // append all unvisited successors to work list |
aoqi@0 | 744 | for (i = cur->number_of_sux() - 1; i >= 0; i--) { |
aoqi@0 | 745 | _work_list.append(cur->sux_at(i)); |
aoqi@0 | 746 | } |
aoqi@0 | 747 | for (i = cur->number_of_exception_handlers() - 1; i >= 0; i--) { |
aoqi@0 | 748 | _work_list.append(cur->exception_handler_at(i)); |
aoqi@0 | 749 | } |
aoqi@0 | 750 | } |
aoqi@0 | 751 | } while (!_work_list.is_empty()); |
aoqi@0 | 752 | } |
aoqi@0 | 753 | |
aoqi@0 | 754 | |
aoqi@0 | 755 | BlockBegin* ComputeLinearScanOrder::common_dominator(BlockBegin* a, BlockBegin* b) { |
aoqi@0 | 756 | assert(a != NULL && b != NULL, "must have input blocks"); |
aoqi@0 | 757 | |
aoqi@0 | 758 | _dominator_blocks.clear(); |
aoqi@0 | 759 | while (a != NULL) { |
aoqi@0 | 760 | _dominator_blocks.set_bit(a->block_id()); |
aoqi@0 | 761 | assert(a->dominator() != NULL || a == _linear_scan_order->at(0), "dominator must be initialized"); |
aoqi@0 | 762 | a = a->dominator(); |
aoqi@0 | 763 | } |
aoqi@0 | 764 | while (b != NULL && !_dominator_blocks.at(b->block_id())) { |
aoqi@0 | 765 | assert(b->dominator() != NULL || b == _linear_scan_order->at(0), "dominator must be initialized"); |
aoqi@0 | 766 | b = b->dominator(); |
aoqi@0 | 767 | } |
aoqi@0 | 768 | |
aoqi@0 | 769 | assert(b != NULL, "could not find dominator"); |
aoqi@0 | 770 | return b; |
aoqi@0 | 771 | } |
aoqi@0 | 772 | |
aoqi@0 | 773 | void ComputeLinearScanOrder::compute_dominator(BlockBegin* cur, BlockBegin* parent) { |
aoqi@0 | 774 | if (cur->dominator() == NULL) { |
aoqi@0 | 775 | TRACE_LINEAR_SCAN(4, tty->print_cr("DOM: initializing dominator of B%d to B%d", cur->block_id(), parent->block_id())); |
aoqi@0 | 776 | cur->set_dominator(parent); |
aoqi@0 | 777 | |
aoqi@0 | 778 | } else if (!(cur->is_set(BlockBegin::linear_scan_loop_header_flag) && parent->is_set(BlockBegin::linear_scan_loop_end_flag))) { |
aoqi@0 | 779 | TRACE_LINEAR_SCAN(4, tty->print_cr("DOM: computing dominator of B%d: common dominator of B%d and B%d is B%d", cur->block_id(), parent->block_id(), cur->dominator()->block_id(), common_dominator(cur->dominator(), parent)->block_id())); |
aoqi@0 | 780 | // Does not hold for exception blocks |
aoqi@0 | 781 | assert(cur->number_of_preds() > 1 || cur->is_set(BlockBegin::exception_entry_flag), ""); |
aoqi@0 | 782 | cur->set_dominator(common_dominator(cur->dominator(), parent)); |
aoqi@0 | 783 | } |
aoqi@0 | 784 | |
aoqi@0 | 785 | // Additional edge to xhandler of all our successors |
aoqi@0 | 786 | // range check elimination needs that the state at the end of a |
aoqi@0 | 787 | // block be valid in every block it dominates so cur must dominate |
aoqi@0 | 788 | // the exception handlers of its successors. |
aoqi@0 | 789 | int num_cur_xhandler = cur->number_of_exception_handlers(); |
aoqi@0 | 790 | for (int j = 0; j < num_cur_xhandler; j++) { |
aoqi@0 | 791 | BlockBegin* xhandler = cur->exception_handler_at(j); |
aoqi@0 | 792 | compute_dominator(xhandler, parent); |
aoqi@0 | 793 | } |
aoqi@0 | 794 | } |
aoqi@0 | 795 | |
aoqi@0 | 796 | |
aoqi@0 | 797 | int ComputeLinearScanOrder::compute_weight(BlockBegin* cur) { |
aoqi@0 | 798 | BlockBegin* single_sux = NULL; |
aoqi@0 | 799 | if (cur->number_of_sux() == 1) { |
aoqi@0 | 800 | single_sux = cur->sux_at(0); |
aoqi@0 | 801 | } |
aoqi@0 | 802 | |
aoqi@0 | 803 | // limit loop-depth to 15 bit (only for security reason, it will never be so big) |
aoqi@0 | 804 | int weight = (cur->loop_depth() & 0x7FFF) << 16; |
aoqi@0 | 805 | |
aoqi@0 | 806 | // general macro for short definition of weight flags |
aoqi@0 | 807 | // the first instance of INC_WEIGHT_IF has the highest priority |
aoqi@0 | 808 | int cur_bit = 15; |
aoqi@0 | 809 | #define INC_WEIGHT_IF(condition) if ((condition)) { weight |= (1 << cur_bit); } cur_bit--; |
aoqi@0 | 810 | |
aoqi@0 | 811 | // this is necessery for the (very rare) case that two successing blocks have |
aoqi@0 | 812 | // the same loop depth, but a different loop index (can happen for endless loops |
aoqi@0 | 813 | // with exception handlers) |
aoqi@0 | 814 | INC_WEIGHT_IF(!cur->is_set(BlockBegin::linear_scan_loop_header_flag)); |
aoqi@0 | 815 | |
aoqi@0 | 816 | // loop end blocks (blocks that end with a backward branch) are added |
aoqi@0 | 817 | // after all other blocks of the loop. |
aoqi@0 | 818 | INC_WEIGHT_IF(!cur->is_set(BlockBegin::linear_scan_loop_end_flag)); |
aoqi@0 | 819 | |
aoqi@0 | 820 | // critical edge split blocks are prefered because than they have a bigger |
aoqi@0 | 821 | // proability to be completely empty |
aoqi@0 | 822 | INC_WEIGHT_IF(cur->is_set(BlockBegin::critical_edge_split_flag)); |
aoqi@0 | 823 | |
aoqi@0 | 824 | // exceptions should not be thrown in normal control flow, so these blocks |
aoqi@0 | 825 | // are added as late as possible |
aoqi@0 | 826 | INC_WEIGHT_IF(cur->end()->as_Throw() == NULL && (single_sux == NULL || single_sux->end()->as_Throw() == NULL)); |
aoqi@0 | 827 | INC_WEIGHT_IF(cur->end()->as_Return() == NULL && (single_sux == NULL || single_sux->end()->as_Return() == NULL)); |
aoqi@0 | 828 | |
aoqi@0 | 829 | // exceptions handlers are added as late as possible |
aoqi@0 | 830 | INC_WEIGHT_IF(!cur->is_set(BlockBegin::exception_entry_flag)); |
aoqi@0 | 831 | |
aoqi@0 | 832 | // guarantee that weight is > 0 |
aoqi@0 | 833 | weight |= 1; |
aoqi@0 | 834 | |
aoqi@0 | 835 | #undef INC_WEIGHT_IF |
aoqi@0 | 836 | assert(cur_bit >= 0, "too many flags"); |
aoqi@0 | 837 | assert(weight > 0, "weight cannot become negative"); |
aoqi@0 | 838 | |
aoqi@0 | 839 | return weight; |
aoqi@0 | 840 | } |
aoqi@0 | 841 | |
aoqi@0 | 842 | bool ComputeLinearScanOrder::ready_for_processing(BlockBegin* cur) { |
aoqi@0 | 843 | // Discount the edge just traveled. |
aoqi@0 | 844 | // When the number drops to zero, all forward branches were processed |
aoqi@0 | 845 | if (dec_forward_branches(cur) != 0) { |
aoqi@0 | 846 | return false; |
aoqi@0 | 847 | } |
aoqi@0 | 848 | |
aoqi@0 | 849 | assert(_linear_scan_order->index_of(cur) == -1, "block already processed (block can be ready only once)"); |
aoqi@0 | 850 | assert(_work_list.index_of(cur) == -1, "block already in work-list (block can be ready only once)"); |
aoqi@0 | 851 | return true; |
aoqi@0 | 852 | } |
aoqi@0 | 853 | |
aoqi@0 | 854 | void ComputeLinearScanOrder::sort_into_work_list(BlockBegin* cur) { |
aoqi@0 | 855 | assert(_work_list.index_of(cur) == -1, "block already in work list"); |
aoqi@0 | 856 | |
aoqi@0 | 857 | int cur_weight = compute_weight(cur); |
aoqi@0 | 858 | |
aoqi@0 | 859 | // the linear_scan_number is used to cache the weight of a block |
aoqi@0 | 860 | cur->set_linear_scan_number(cur_weight); |
aoqi@0 | 861 | |
aoqi@0 | 862 | #ifndef PRODUCT |
aoqi@0 | 863 | if (StressLinearScan) { |
aoqi@0 | 864 | _work_list.insert_before(0, cur); |
aoqi@0 | 865 | return; |
aoqi@0 | 866 | } |
aoqi@0 | 867 | #endif |
aoqi@0 | 868 | |
aoqi@0 | 869 | _work_list.append(NULL); // provide space for new element |
aoqi@0 | 870 | |
aoqi@0 | 871 | int insert_idx = _work_list.length() - 1; |
aoqi@0 | 872 | while (insert_idx > 0 && _work_list.at(insert_idx - 1)->linear_scan_number() > cur_weight) { |
aoqi@0 | 873 | _work_list.at_put(insert_idx, _work_list.at(insert_idx - 1)); |
aoqi@0 | 874 | insert_idx--; |
aoqi@0 | 875 | } |
aoqi@0 | 876 | _work_list.at_put(insert_idx, cur); |
aoqi@0 | 877 | |
aoqi@0 | 878 | TRACE_LINEAR_SCAN(3, tty->print_cr("Sorted B%d into worklist. new worklist:", cur->block_id())); |
aoqi@0 | 879 | TRACE_LINEAR_SCAN(3, for (int i = 0; i < _work_list.length(); i++) tty->print_cr("%8d B%2d weight:%6x", i, _work_list.at(i)->block_id(), _work_list.at(i)->linear_scan_number())); |
aoqi@0 | 880 | |
aoqi@0 | 881 | #ifdef ASSERT |
aoqi@0 | 882 | for (int i = 0; i < _work_list.length(); i++) { |
aoqi@0 | 883 | assert(_work_list.at(i)->linear_scan_number() > 0, "weight not set"); |
aoqi@0 | 884 | assert(i == 0 || _work_list.at(i - 1)->linear_scan_number() <= _work_list.at(i)->linear_scan_number(), "incorrect order in worklist"); |
aoqi@0 | 885 | } |
aoqi@0 | 886 | #endif |
aoqi@0 | 887 | } |
aoqi@0 | 888 | |
aoqi@0 | 889 | void ComputeLinearScanOrder::append_block(BlockBegin* cur) { |
aoqi@0 | 890 | TRACE_LINEAR_SCAN(3, tty->print_cr("appending block B%d (weight 0x%6x) to linear-scan order", cur->block_id(), cur->linear_scan_number())); |
aoqi@0 | 891 | assert(_linear_scan_order->index_of(cur) == -1, "cannot add the same block twice"); |
aoqi@0 | 892 | |
aoqi@0 | 893 | // currently, the linear scan order and code emit order are equal. |
aoqi@0 | 894 | // therefore the linear_scan_number and the weight of a block must also |
aoqi@0 | 895 | // be equal. |
aoqi@0 | 896 | cur->set_linear_scan_number(_linear_scan_order->length()); |
aoqi@0 | 897 | _linear_scan_order->append(cur); |
aoqi@0 | 898 | } |
aoqi@0 | 899 | |
aoqi@0 | 900 | void ComputeLinearScanOrder::compute_order(BlockBegin* start_block) { |
aoqi@0 | 901 | TRACE_LINEAR_SCAN(3, tty->print_cr("----- computing final block order")); |
aoqi@0 | 902 | |
aoqi@0 | 903 | // the start block is always the first block in the linear scan order |
aoqi@0 | 904 | _linear_scan_order = new BlockList(_num_blocks); |
aoqi@0 | 905 | append_block(start_block); |
aoqi@0 | 906 | |
aoqi@0 | 907 | assert(start_block->end()->as_Base() != NULL, "start block must end with Base-instruction"); |
aoqi@0 | 908 | BlockBegin* std_entry = ((Base*)start_block->end())->std_entry(); |
aoqi@0 | 909 | BlockBegin* osr_entry = ((Base*)start_block->end())->osr_entry(); |
aoqi@0 | 910 | |
aoqi@0 | 911 | BlockBegin* sux_of_osr_entry = NULL; |
aoqi@0 | 912 | if (osr_entry != NULL) { |
aoqi@0 | 913 | // special handling for osr entry: |
aoqi@0 | 914 | // ignore the edge between the osr entry and its successor for processing |
aoqi@0 | 915 | // the osr entry block is added manually below |
aoqi@0 | 916 | assert(osr_entry->number_of_sux() == 1, "osr entry must have exactly one successor"); |
aoqi@0 | 917 | assert(osr_entry->sux_at(0)->number_of_preds() >= 2, "sucessor of osr entry must have two predecessors (otherwise it is not present in normal control flow"); |
aoqi@0 | 918 | |
aoqi@0 | 919 | sux_of_osr_entry = osr_entry->sux_at(0); |
aoqi@0 | 920 | dec_forward_branches(sux_of_osr_entry); |
aoqi@0 | 921 | |
aoqi@0 | 922 | compute_dominator(osr_entry, start_block); |
aoqi@0 | 923 | _iterative_dominators = true; |
aoqi@0 | 924 | } |
aoqi@0 | 925 | compute_dominator(std_entry, start_block); |
aoqi@0 | 926 | |
aoqi@0 | 927 | // start processing with standard entry block |
aoqi@0 | 928 | assert(_work_list.is_empty(), "list must be empty before processing"); |
aoqi@0 | 929 | |
aoqi@0 | 930 | if (ready_for_processing(std_entry)) { |
aoqi@0 | 931 | sort_into_work_list(std_entry); |
aoqi@0 | 932 | } else { |
aoqi@0 | 933 | assert(false, "the std_entry must be ready for processing (otherwise, the method has no start block)"); |
aoqi@0 | 934 | } |
aoqi@0 | 935 | |
aoqi@0 | 936 | do { |
aoqi@0 | 937 | BlockBegin* cur = _work_list.pop(); |
aoqi@0 | 938 | |
aoqi@0 | 939 | if (cur == sux_of_osr_entry) { |
aoqi@0 | 940 | // the osr entry block is ignored in normal processing, it is never added to the |
aoqi@0 | 941 | // work list. Instead, it is added as late as possible manually here. |
aoqi@0 | 942 | append_block(osr_entry); |
aoqi@0 | 943 | compute_dominator(cur, osr_entry); |
aoqi@0 | 944 | } |
aoqi@0 | 945 | append_block(cur); |
aoqi@0 | 946 | |
aoqi@0 | 947 | int i; |
aoqi@0 | 948 | int num_sux = cur->number_of_sux(); |
aoqi@0 | 949 | // changed loop order to get "intuitive" order of if- and else-blocks |
aoqi@0 | 950 | for (i = 0; i < num_sux; i++) { |
aoqi@0 | 951 | BlockBegin* sux = cur->sux_at(i); |
aoqi@0 | 952 | compute_dominator(sux, cur); |
aoqi@0 | 953 | if (ready_for_processing(sux)) { |
aoqi@0 | 954 | sort_into_work_list(sux); |
aoqi@0 | 955 | } |
aoqi@0 | 956 | } |
aoqi@0 | 957 | num_sux = cur->number_of_exception_handlers(); |
aoqi@0 | 958 | for (i = 0; i < num_sux; i++) { |
aoqi@0 | 959 | BlockBegin* sux = cur->exception_handler_at(i); |
aoqi@0 | 960 | if (ready_for_processing(sux)) { |
aoqi@0 | 961 | sort_into_work_list(sux); |
aoqi@0 | 962 | } |
aoqi@0 | 963 | } |
aoqi@0 | 964 | } while (_work_list.length() > 0); |
aoqi@0 | 965 | } |
aoqi@0 | 966 | |
aoqi@0 | 967 | |
aoqi@0 | 968 | bool ComputeLinearScanOrder::compute_dominators_iter() { |
aoqi@0 | 969 | bool changed = false; |
aoqi@0 | 970 | int num_blocks = _linear_scan_order->length(); |
aoqi@0 | 971 | |
aoqi@0 | 972 | assert(_linear_scan_order->at(0)->dominator() == NULL, "must not have dominator"); |
aoqi@0 | 973 | assert(_linear_scan_order->at(0)->number_of_preds() == 0, "must not have predecessors"); |
aoqi@0 | 974 | for (int i = 1; i < num_blocks; i++) { |
aoqi@0 | 975 | BlockBegin* block = _linear_scan_order->at(i); |
aoqi@0 | 976 | |
aoqi@0 | 977 | BlockBegin* dominator = block->pred_at(0); |
aoqi@0 | 978 | int num_preds = block->number_of_preds(); |
aoqi@0 | 979 | |
aoqi@0 | 980 | TRACE_LINEAR_SCAN(4, tty->print_cr("DOM: Processing B%d", block->block_id())); |
aoqi@0 | 981 | |
aoqi@0 | 982 | for (int j = 0; j < num_preds; j++) { |
aoqi@0 | 983 | |
aoqi@0 | 984 | BlockBegin *pred = block->pred_at(j); |
aoqi@0 | 985 | TRACE_LINEAR_SCAN(4, tty->print_cr(" DOM: Subrocessing B%d", pred->block_id())); |
aoqi@0 | 986 | |
aoqi@0 | 987 | if (block->is_set(BlockBegin::exception_entry_flag)) { |
aoqi@0 | 988 | dominator = common_dominator(dominator, pred); |
aoqi@0 | 989 | int num_pred_preds = pred->number_of_preds(); |
aoqi@0 | 990 | for (int k = 0; k < num_pred_preds; k++) { |
aoqi@0 | 991 | dominator = common_dominator(dominator, pred->pred_at(k)); |
aoqi@0 | 992 | } |
aoqi@0 | 993 | } else { |
aoqi@0 | 994 | dominator = common_dominator(dominator, pred); |
aoqi@0 | 995 | } |
aoqi@0 | 996 | } |
aoqi@0 | 997 | |
aoqi@0 | 998 | if (dominator != block->dominator()) { |
aoqi@0 | 999 | TRACE_LINEAR_SCAN(4, tty->print_cr("DOM: updating dominator of B%d from B%d to B%d", block->block_id(), block->dominator()->block_id(), dominator->block_id())); |
aoqi@0 | 1000 | |
aoqi@0 | 1001 | block->set_dominator(dominator); |
aoqi@0 | 1002 | changed = true; |
aoqi@0 | 1003 | } |
aoqi@0 | 1004 | } |
aoqi@0 | 1005 | return changed; |
aoqi@0 | 1006 | } |
aoqi@0 | 1007 | |
aoqi@0 | 1008 | void ComputeLinearScanOrder::compute_dominators() { |
aoqi@0 | 1009 | TRACE_LINEAR_SCAN(3, tty->print_cr("----- computing dominators (iterative computation reqired: %d)", _iterative_dominators)); |
aoqi@0 | 1010 | |
aoqi@0 | 1011 | // iterative computation of dominators is only required for methods with non-natural loops |
aoqi@0 | 1012 | // and OSR-methods. For all other methods, the dominators computed when generating the |
aoqi@0 | 1013 | // linear scan block order are correct. |
aoqi@0 | 1014 | if (_iterative_dominators) { |
aoqi@0 | 1015 | do { |
aoqi@0 | 1016 | TRACE_LINEAR_SCAN(1, tty->print_cr("DOM: next iteration of fix-point calculation")); |
aoqi@0 | 1017 | } while (compute_dominators_iter()); |
aoqi@0 | 1018 | } |
aoqi@0 | 1019 | |
aoqi@0 | 1020 | // check that dominators are correct |
aoqi@0 | 1021 | assert(!compute_dominators_iter(), "fix point not reached"); |
aoqi@0 | 1022 | |
aoqi@0 | 1023 | // Add Blocks to dominates-Array |
aoqi@0 | 1024 | int num_blocks = _linear_scan_order->length(); |
aoqi@0 | 1025 | for (int i = 0; i < num_blocks; i++) { |
aoqi@0 | 1026 | BlockBegin* block = _linear_scan_order->at(i); |
aoqi@0 | 1027 | |
aoqi@0 | 1028 | BlockBegin *dom = block->dominator(); |
aoqi@0 | 1029 | if (dom) { |
aoqi@0 | 1030 | assert(dom->dominator_depth() != -1, "Dominator must have been visited before"); |
aoqi@0 | 1031 | dom->dominates()->append(block); |
aoqi@0 | 1032 | block->set_dominator_depth(dom->dominator_depth() + 1); |
aoqi@0 | 1033 | } else { |
aoqi@0 | 1034 | block->set_dominator_depth(0); |
aoqi@0 | 1035 | } |
aoqi@0 | 1036 | } |
aoqi@0 | 1037 | } |
aoqi@0 | 1038 | |
aoqi@0 | 1039 | |
aoqi@0 | 1040 | #ifndef PRODUCT |
aoqi@0 | 1041 | void ComputeLinearScanOrder::print_blocks() { |
aoqi@0 | 1042 | if (TraceLinearScanLevel >= 2) { |
aoqi@0 | 1043 | tty->print_cr("----- loop information:"); |
aoqi@0 | 1044 | for (int block_idx = 0; block_idx < _linear_scan_order->length(); block_idx++) { |
aoqi@0 | 1045 | BlockBegin* cur = _linear_scan_order->at(block_idx); |
aoqi@0 | 1046 | |
aoqi@0 | 1047 | tty->print("%4d: B%2d: ", cur->linear_scan_number(), cur->block_id()); |
aoqi@0 | 1048 | for (int loop_idx = 0; loop_idx < _num_loops; loop_idx++) { |
aoqi@0 | 1049 | tty->print ("%d ", is_block_in_loop(loop_idx, cur)); |
aoqi@0 | 1050 | } |
aoqi@0 | 1051 | tty->print_cr(" -> loop_index: %2d, loop_depth: %2d", cur->loop_index(), cur->loop_depth()); |
aoqi@0 | 1052 | } |
aoqi@0 | 1053 | } |
aoqi@0 | 1054 | |
aoqi@0 | 1055 | if (TraceLinearScanLevel >= 1) { |
aoqi@0 | 1056 | tty->print_cr("----- linear-scan block order:"); |
aoqi@0 | 1057 | for (int block_idx = 0; block_idx < _linear_scan_order->length(); block_idx++) { |
aoqi@0 | 1058 | BlockBegin* cur = _linear_scan_order->at(block_idx); |
aoqi@0 | 1059 | tty->print("%4d: B%2d loop: %2d depth: %2d", cur->linear_scan_number(), cur->block_id(), cur->loop_index(), cur->loop_depth()); |
aoqi@0 | 1060 | |
aoqi@0 | 1061 | tty->print(cur->is_set(BlockBegin::exception_entry_flag) ? " ex" : " "); |
aoqi@0 | 1062 | tty->print(cur->is_set(BlockBegin::critical_edge_split_flag) ? " ce" : " "); |
aoqi@0 | 1063 | tty->print(cur->is_set(BlockBegin::linear_scan_loop_header_flag) ? " lh" : " "); |
aoqi@0 | 1064 | tty->print(cur->is_set(BlockBegin::linear_scan_loop_end_flag) ? " le" : " "); |
aoqi@0 | 1065 | |
aoqi@0 | 1066 | if (cur->dominator() != NULL) { |
aoqi@0 | 1067 | tty->print(" dom: B%d ", cur->dominator()->block_id()); |
aoqi@0 | 1068 | } else { |
aoqi@0 | 1069 | tty->print(" dom: NULL "); |
aoqi@0 | 1070 | } |
aoqi@0 | 1071 | |
aoqi@0 | 1072 | if (cur->number_of_preds() > 0) { |
aoqi@0 | 1073 | tty->print(" preds: "); |
aoqi@0 | 1074 | for (int j = 0; j < cur->number_of_preds(); j++) { |
aoqi@0 | 1075 | BlockBegin* pred = cur->pred_at(j); |
aoqi@0 | 1076 | tty->print("B%d ", pred->block_id()); |
aoqi@0 | 1077 | } |
aoqi@0 | 1078 | } |
aoqi@0 | 1079 | if (cur->number_of_sux() > 0) { |
aoqi@0 | 1080 | tty->print(" sux: "); |
aoqi@0 | 1081 | for (int j = 0; j < cur->number_of_sux(); j++) { |
aoqi@0 | 1082 | BlockBegin* sux = cur->sux_at(j); |
aoqi@0 | 1083 | tty->print("B%d ", sux->block_id()); |
aoqi@0 | 1084 | } |
aoqi@0 | 1085 | } |
aoqi@0 | 1086 | if (cur->number_of_exception_handlers() > 0) { |
aoqi@0 | 1087 | tty->print(" ex: "); |
aoqi@0 | 1088 | for (int j = 0; j < cur->number_of_exception_handlers(); j++) { |
aoqi@0 | 1089 | BlockBegin* ex = cur->exception_handler_at(j); |
aoqi@0 | 1090 | tty->print("B%d ", ex->block_id()); |
aoqi@0 | 1091 | } |
aoqi@0 | 1092 | } |
aoqi@0 | 1093 | tty->cr(); |
aoqi@0 | 1094 | } |
aoqi@0 | 1095 | } |
aoqi@0 | 1096 | } |
aoqi@0 | 1097 | #endif |
aoqi@0 | 1098 | |
aoqi@0 | 1099 | #ifdef ASSERT |
aoqi@0 | 1100 | void ComputeLinearScanOrder::verify() { |
aoqi@0 | 1101 | assert(_linear_scan_order->length() == _num_blocks, "wrong number of blocks in list"); |
aoqi@0 | 1102 | |
aoqi@0 | 1103 | if (StressLinearScan) { |
aoqi@0 | 1104 | // blocks are scrambled when StressLinearScan is used |
aoqi@0 | 1105 | return; |
aoqi@0 | 1106 | } |
aoqi@0 | 1107 | |
aoqi@0 | 1108 | // check that all successors of a block have a higher linear-scan-number |
aoqi@0 | 1109 | // and that all predecessors of a block have a lower linear-scan-number |
aoqi@0 | 1110 | // (only backward branches of loops are ignored) |
aoqi@0 | 1111 | int i; |
aoqi@0 | 1112 | for (i = 0; i < _linear_scan_order->length(); i++) { |
aoqi@0 | 1113 | BlockBegin* cur = _linear_scan_order->at(i); |
aoqi@0 | 1114 | |
aoqi@0 | 1115 | assert(cur->linear_scan_number() == i, "incorrect linear_scan_number"); |
aoqi@0 | 1116 | assert(cur->linear_scan_number() >= 0 && cur->linear_scan_number() == _linear_scan_order->index_of(cur), "incorrect linear_scan_number"); |
aoqi@0 | 1117 | |
aoqi@0 | 1118 | int j; |
aoqi@0 | 1119 | for (j = cur->number_of_sux() - 1; j >= 0; j--) { |
aoqi@0 | 1120 | BlockBegin* sux = cur->sux_at(j); |
aoqi@0 | 1121 | |
aoqi@0 | 1122 | assert(sux->linear_scan_number() >= 0 && sux->linear_scan_number() == _linear_scan_order->index_of(sux), "incorrect linear_scan_number"); |
aoqi@0 | 1123 | if (!sux->is_set(BlockBegin::backward_branch_target_flag)) { |
aoqi@0 | 1124 | assert(cur->linear_scan_number() < sux->linear_scan_number(), "invalid order"); |
aoqi@0 | 1125 | } |
aoqi@0 | 1126 | if (cur->loop_depth() == sux->loop_depth()) { |
aoqi@0 | 1127 | assert(cur->loop_index() == sux->loop_index() || sux->is_set(BlockBegin::linear_scan_loop_header_flag), "successing blocks with same loop depth must have same loop index"); |
aoqi@0 | 1128 | } |
aoqi@0 | 1129 | } |
aoqi@0 | 1130 | |
aoqi@0 | 1131 | for (j = cur->number_of_preds() - 1; j >= 0; j--) { |
aoqi@0 | 1132 | BlockBegin* pred = cur->pred_at(j); |
aoqi@0 | 1133 | |
aoqi@0 | 1134 | assert(pred->linear_scan_number() >= 0 && pred->linear_scan_number() == _linear_scan_order->index_of(pred), "incorrect linear_scan_number"); |
aoqi@0 | 1135 | if (!cur->is_set(BlockBegin::backward_branch_target_flag)) { |
aoqi@0 | 1136 | assert(cur->linear_scan_number() > pred->linear_scan_number(), "invalid order"); |
aoqi@0 | 1137 | } |
aoqi@0 | 1138 | if (cur->loop_depth() == pred->loop_depth()) { |
aoqi@0 | 1139 | assert(cur->loop_index() == pred->loop_index() || cur->is_set(BlockBegin::linear_scan_loop_header_flag), "successing blocks with same loop depth must have same loop index"); |
aoqi@0 | 1140 | } |
aoqi@0 | 1141 | |
aoqi@0 | 1142 | assert(cur->dominator()->linear_scan_number() <= cur->pred_at(j)->linear_scan_number(), "dominator must be before predecessors"); |
aoqi@0 | 1143 | } |
aoqi@0 | 1144 | |
aoqi@0 | 1145 | // check dominator |
aoqi@0 | 1146 | if (i == 0) { |
aoqi@0 | 1147 | assert(cur->dominator() == NULL, "first block has no dominator"); |
aoqi@0 | 1148 | } else { |
aoqi@0 | 1149 | assert(cur->dominator() != NULL, "all but first block must have dominator"); |
aoqi@0 | 1150 | } |
aoqi@0 | 1151 | // Assertion does not hold for exception handlers |
aoqi@0 | 1152 | assert(cur->number_of_preds() != 1 || cur->dominator() == cur->pred_at(0) || cur->is_set(BlockBegin::exception_entry_flag), "Single predecessor must also be dominator"); |
aoqi@0 | 1153 | } |
aoqi@0 | 1154 | |
aoqi@0 | 1155 | // check that all loops are continuous |
aoqi@0 | 1156 | for (int loop_idx = 0; loop_idx < _num_loops; loop_idx++) { |
aoqi@0 | 1157 | int block_idx = 0; |
aoqi@0 | 1158 | assert(!is_block_in_loop(loop_idx, _linear_scan_order->at(block_idx)), "the first block must not be present in any loop"); |
aoqi@0 | 1159 | |
aoqi@0 | 1160 | // skip blocks before the loop |
aoqi@0 | 1161 | while (block_idx < _num_blocks && !is_block_in_loop(loop_idx, _linear_scan_order->at(block_idx))) { |
aoqi@0 | 1162 | block_idx++; |
aoqi@0 | 1163 | } |
aoqi@0 | 1164 | // skip blocks of loop |
aoqi@0 | 1165 | while (block_idx < _num_blocks && is_block_in_loop(loop_idx, _linear_scan_order->at(block_idx))) { |
aoqi@0 | 1166 | block_idx++; |
aoqi@0 | 1167 | } |
aoqi@0 | 1168 | // after the first non-loop block, there must not be another loop-block |
aoqi@0 | 1169 | while (block_idx < _num_blocks) { |
aoqi@0 | 1170 | assert(!is_block_in_loop(loop_idx, _linear_scan_order->at(block_idx)), "loop not continuous in linear-scan order"); |
aoqi@0 | 1171 | block_idx++; |
aoqi@0 | 1172 | } |
aoqi@0 | 1173 | } |
aoqi@0 | 1174 | } |
aoqi@0 | 1175 | #endif |
aoqi@0 | 1176 | |
aoqi@0 | 1177 | |
aoqi@0 | 1178 | void IR::compute_code() { |
aoqi@0 | 1179 | assert(is_valid(), "IR must be valid"); |
aoqi@0 | 1180 | |
aoqi@0 | 1181 | ComputeLinearScanOrder compute_order(compilation(), start()); |
aoqi@0 | 1182 | _num_loops = compute_order.num_loops(); |
aoqi@0 | 1183 | _code = compute_order.linear_scan_order(); |
aoqi@0 | 1184 | } |
aoqi@0 | 1185 | |
aoqi@0 | 1186 | |
aoqi@0 | 1187 | void IR::compute_use_counts() { |
aoqi@0 | 1188 | // make sure all values coming out of this block get evaluated. |
aoqi@0 | 1189 | int num_blocks = _code->length(); |
aoqi@0 | 1190 | for (int i = 0; i < num_blocks; i++) { |
aoqi@0 | 1191 | _code->at(i)->end()->state()->pin_stack_for_linear_scan(); |
aoqi@0 | 1192 | } |
aoqi@0 | 1193 | |
aoqi@0 | 1194 | // compute use counts |
aoqi@0 | 1195 | UseCountComputer::compute(_code); |
aoqi@0 | 1196 | } |
aoqi@0 | 1197 | |
aoqi@0 | 1198 | |
aoqi@0 | 1199 | void IR::iterate_preorder(BlockClosure* closure) { |
aoqi@0 | 1200 | assert(is_valid(), "IR must be valid"); |
aoqi@0 | 1201 | start()->iterate_preorder(closure); |
aoqi@0 | 1202 | } |
aoqi@0 | 1203 | |
aoqi@0 | 1204 | |
aoqi@0 | 1205 | void IR::iterate_postorder(BlockClosure* closure) { |
aoqi@0 | 1206 | assert(is_valid(), "IR must be valid"); |
aoqi@0 | 1207 | start()->iterate_postorder(closure); |
aoqi@0 | 1208 | } |
aoqi@0 | 1209 | |
aoqi@0 | 1210 | void IR::iterate_linear_scan_order(BlockClosure* closure) { |
aoqi@0 | 1211 | linear_scan_order()->iterate_forward(closure); |
aoqi@0 | 1212 | } |
aoqi@0 | 1213 | |
aoqi@0 | 1214 | |
aoqi@0 | 1215 | #ifndef PRODUCT |
aoqi@0 | 1216 | class BlockPrinter: public BlockClosure { |
aoqi@0 | 1217 | private: |
aoqi@0 | 1218 | InstructionPrinter* _ip; |
aoqi@0 | 1219 | bool _cfg_only; |
aoqi@0 | 1220 | bool _live_only; |
aoqi@0 | 1221 | |
aoqi@0 | 1222 | public: |
aoqi@0 | 1223 | BlockPrinter(InstructionPrinter* ip, bool cfg_only, bool live_only = false) { |
aoqi@0 | 1224 | _ip = ip; |
aoqi@0 | 1225 | _cfg_only = cfg_only; |
aoqi@0 | 1226 | _live_only = live_only; |
aoqi@0 | 1227 | } |
aoqi@0 | 1228 | |
aoqi@0 | 1229 | virtual void block_do(BlockBegin* block) { |
aoqi@0 | 1230 | if (_cfg_only) { |
aoqi@0 | 1231 | _ip->print_instr(block); tty->cr(); |
aoqi@0 | 1232 | } else { |
aoqi@0 | 1233 | block->print_block(*_ip, _live_only); |
aoqi@0 | 1234 | } |
aoqi@0 | 1235 | } |
aoqi@0 | 1236 | }; |
aoqi@0 | 1237 | |
aoqi@0 | 1238 | |
aoqi@0 | 1239 | void IR::print(BlockBegin* start, bool cfg_only, bool live_only) { |
aoqi@0 | 1240 | ttyLocker ttyl; |
aoqi@0 | 1241 | InstructionPrinter ip(!cfg_only); |
aoqi@0 | 1242 | BlockPrinter bp(&ip, cfg_only, live_only); |
aoqi@0 | 1243 | start->iterate_preorder(&bp); |
aoqi@0 | 1244 | tty->cr(); |
aoqi@0 | 1245 | } |
aoqi@0 | 1246 | |
aoqi@0 | 1247 | void IR::print(bool cfg_only, bool live_only) { |
aoqi@0 | 1248 | if (is_valid()) { |
aoqi@0 | 1249 | print(start(), cfg_only, live_only); |
aoqi@0 | 1250 | } else { |
aoqi@0 | 1251 | tty->print_cr("invalid IR"); |
aoqi@0 | 1252 | } |
aoqi@0 | 1253 | } |
aoqi@0 | 1254 | |
aoqi@0 | 1255 | |
aoqi@0 | 1256 | define_array(BlockListArray, BlockList*) |
aoqi@0 | 1257 | define_stack(BlockListList, BlockListArray) |
aoqi@0 | 1258 | |
aoqi@0 | 1259 | class PredecessorValidator : public BlockClosure { |
aoqi@0 | 1260 | private: |
aoqi@0 | 1261 | BlockListList* _predecessors; |
aoqi@0 | 1262 | BlockList* _blocks; |
aoqi@0 | 1263 | |
aoqi@0 | 1264 | static int cmp(BlockBegin** a, BlockBegin** b) { |
aoqi@0 | 1265 | return (*a)->block_id() - (*b)->block_id(); |
aoqi@0 | 1266 | } |
aoqi@0 | 1267 | |
aoqi@0 | 1268 | public: |
aoqi@0 | 1269 | PredecessorValidator(IR* hir) { |
aoqi@0 | 1270 | ResourceMark rm; |
aoqi@0 | 1271 | _predecessors = new BlockListList(BlockBegin::number_of_blocks(), NULL); |
aoqi@0 | 1272 | _blocks = new BlockList(); |
aoqi@0 | 1273 | |
aoqi@0 | 1274 | int i; |
aoqi@0 | 1275 | hir->start()->iterate_preorder(this); |
aoqi@0 | 1276 | if (hir->code() != NULL) { |
aoqi@0 | 1277 | assert(hir->code()->length() == _blocks->length(), "must match"); |
aoqi@0 | 1278 | for (i = 0; i < _blocks->length(); i++) { |
aoqi@0 | 1279 | assert(hir->code()->contains(_blocks->at(i)), "should be in both lists"); |
aoqi@0 | 1280 | } |
aoqi@0 | 1281 | } |
aoqi@0 | 1282 | |
aoqi@0 | 1283 | for (i = 0; i < _blocks->length(); i++) { |
aoqi@0 | 1284 | BlockBegin* block = _blocks->at(i); |
aoqi@0 | 1285 | BlockList* preds = _predecessors->at(block->block_id()); |
aoqi@0 | 1286 | if (preds == NULL) { |
aoqi@0 | 1287 | assert(block->number_of_preds() == 0, "should be the same"); |
aoqi@0 | 1288 | continue; |
aoqi@0 | 1289 | } |
aoqi@0 | 1290 | |
aoqi@0 | 1291 | // clone the pred list so we can mutate it |
aoqi@0 | 1292 | BlockList* pred_copy = new BlockList(); |
aoqi@0 | 1293 | int j; |
aoqi@0 | 1294 | for (j = 0; j < block->number_of_preds(); j++) { |
aoqi@0 | 1295 | pred_copy->append(block->pred_at(j)); |
aoqi@0 | 1296 | } |
aoqi@0 | 1297 | // sort them in the same order |
aoqi@0 | 1298 | preds->sort(cmp); |
aoqi@0 | 1299 | pred_copy->sort(cmp); |
aoqi@0 | 1300 | int length = MIN2(preds->length(), block->number_of_preds()); |
aoqi@0 | 1301 | for (j = 0; j < block->number_of_preds(); j++) { |
aoqi@0 | 1302 | assert(preds->at(j) == pred_copy->at(j), "must match"); |
aoqi@0 | 1303 | } |
aoqi@0 | 1304 | |
aoqi@0 | 1305 | assert(preds->length() == block->number_of_preds(), "should be the same"); |
aoqi@0 | 1306 | } |
aoqi@0 | 1307 | } |
aoqi@0 | 1308 | |
aoqi@0 | 1309 | virtual void block_do(BlockBegin* block) { |
aoqi@0 | 1310 | _blocks->append(block); |
aoqi@0 | 1311 | BlockEnd* be = block->end(); |
aoqi@0 | 1312 | int n = be->number_of_sux(); |
aoqi@0 | 1313 | int i; |
aoqi@0 | 1314 | for (i = 0; i < n; i++) { |
aoqi@0 | 1315 | BlockBegin* sux = be->sux_at(i); |
aoqi@0 | 1316 | assert(!sux->is_set(BlockBegin::exception_entry_flag), "must not be xhandler"); |
aoqi@0 | 1317 | |
aoqi@0 | 1318 | BlockList* preds = _predecessors->at_grow(sux->block_id(), NULL); |
aoqi@0 | 1319 | if (preds == NULL) { |
aoqi@0 | 1320 | preds = new BlockList(); |
aoqi@0 | 1321 | _predecessors->at_put(sux->block_id(), preds); |
aoqi@0 | 1322 | } |
aoqi@0 | 1323 | preds->append(block); |
aoqi@0 | 1324 | } |
aoqi@0 | 1325 | |
aoqi@0 | 1326 | n = block->number_of_exception_handlers(); |
aoqi@0 | 1327 | for (i = 0; i < n; i++) { |
aoqi@0 | 1328 | BlockBegin* sux = block->exception_handler_at(i); |
aoqi@0 | 1329 | assert(sux->is_set(BlockBegin::exception_entry_flag), "must be xhandler"); |
aoqi@0 | 1330 | |
aoqi@0 | 1331 | BlockList* preds = _predecessors->at_grow(sux->block_id(), NULL); |
aoqi@0 | 1332 | if (preds == NULL) { |
aoqi@0 | 1333 | preds = new BlockList(); |
aoqi@0 | 1334 | _predecessors->at_put(sux->block_id(), preds); |
aoqi@0 | 1335 | } |
aoqi@0 | 1336 | preds->append(block); |
aoqi@0 | 1337 | } |
aoqi@0 | 1338 | } |
aoqi@0 | 1339 | }; |
aoqi@0 | 1340 | |
aoqi@0 | 1341 | class VerifyBlockBeginField : public BlockClosure { |
aoqi@0 | 1342 | |
aoqi@0 | 1343 | public: |
aoqi@0 | 1344 | |
aoqi@0 | 1345 | virtual void block_do(BlockBegin *block) { |
aoqi@0 | 1346 | for ( Instruction *cur = block; cur != NULL; cur = cur->next()) { |
aoqi@0 | 1347 | assert(cur->block() == block, "Block begin is not correct"); |
aoqi@0 | 1348 | } |
aoqi@0 | 1349 | } |
aoqi@0 | 1350 | }; |
aoqi@0 | 1351 | |
aoqi@0 | 1352 | void IR::verify() { |
aoqi@0 | 1353 | #ifdef ASSERT |
aoqi@0 | 1354 | PredecessorValidator pv(this); |
aoqi@0 | 1355 | VerifyBlockBeginField verifier; |
aoqi@0 | 1356 | this->iterate_postorder(&verifier); |
aoqi@0 | 1357 | #endif |
aoqi@0 | 1358 | } |
aoqi@0 | 1359 | |
aoqi@0 | 1360 | #endif // PRODUCT |
aoqi@0 | 1361 | |
aoqi@0 | 1362 | void SubstitutionResolver::visit(Value* v) { |
aoqi@0 | 1363 | Value v0 = *v; |
aoqi@0 | 1364 | if (v0) { |
aoqi@0 | 1365 | Value vs = v0->subst(); |
aoqi@0 | 1366 | if (vs != v0) { |
aoqi@0 | 1367 | *v = v0->subst(); |
aoqi@0 | 1368 | } |
aoqi@0 | 1369 | } |
aoqi@0 | 1370 | } |
aoqi@0 | 1371 | |
aoqi@0 | 1372 | #ifdef ASSERT |
aoqi@0 | 1373 | class SubstitutionChecker: public ValueVisitor { |
aoqi@0 | 1374 | void visit(Value* v) { |
aoqi@0 | 1375 | Value v0 = *v; |
aoqi@0 | 1376 | if (v0) { |
aoqi@0 | 1377 | Value vs = v0->subst(); |
aoqi@0 | 1378 | assert(vs == v0, "missed substitution"); |
aoqi@0 | 1379 | } |
aoqi@0 | 1380 | } |
aoqi@0 | 1381 | }; |
aoqi@0 | 1382 | #endif |
aoqi@0 | 1383 | |
aoqi@0 | 1384 | |
aoqi@0 | 1385 | void SubstitutionResolver::block_do(BlockBegin* block) { |
aoqi@0 | 1386 | Instruction* last = NULL; |
aoqi@0 | 1387 | for (Instruction* n = block; n != NULL;) { |
aoqi@0 | 1388 | n->values_do(this); |
aoqi@0 | 1389 | // need to remove this instruction from the instruction stream |
aoqi@0 | 1390 | if (n->subst() != n) { |
aoqi@0 | 1391 | assert(last != NULL, "must have last"); |
aoqi@0 | 1392 | last->set_next(n->next()); |
aoqi@0 | 1393 | } else { |
aoqi@0 | 1394 | last = n; |
aoqi@0 | 1395 | } |
aoqi@0 | 1396 | n = last->next(); |
aoqi@0 | 1397 | } |
aoqi@0 | 1398 | |
aoqi@0 | 1399 | #ifdef ASSERT |
aoqi@0 | 1400 | SubstitutionChecker check_substitute; |
aoqi@0 | 1401 | if (block->state()) block->state()->values_do(&check_substitute); |
aoqi@0 | 1402 | block->block_values_do(&check_substitute); |
aoqi@0 | 1403 | if (block->end() && block->end()->state()) block->end()->state()->values_do(&check_substitute); |
aoqi@0 | 1404 | #endif |
aoqi@0 | 1405 | } |