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/*
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* Copyright 1999-2006 Sun Microsystems, Inc. All Rights Reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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* CA 95054 USA or visit www.sun.com if you need additional information or
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* have any questions.
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*
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*/
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# include "incls/_precompiled.incl"
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# include "incls/_c1_IR.cpp.incl"
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// Implementation of XHandlers
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//
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// Note: This code could eventually go away if we are
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// just using the ciExceptionHandlerStream.
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XHandlers::XHandlers(ciMethod* method) : _list(method->exception_table_length()) {
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ciExceptionHandlerStream s(method);
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while (!s.is_done()) {
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_list.append(new XHandler(s.handler()));
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s.next();
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}
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assert(s.count() == method->exception_table_length(), "exception table lengths inconsistent");
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}
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// deep copy of all XHandler contained in list
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XHandlers::XHandlers(XHandlers* other) :
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_list(other->length())
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{
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for (int i = 0; i < other->length(); i++) {
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_list.append(new XHandler(other->handler_at(i)));
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}
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}
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// Returns whether a particular exception type can be caught. Also
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// returns true if klass is unloaded or any exception handler
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// classes are unloaded. type_is_exact indicates whether the throw
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// is known to be exactly that class or it might throw a subtype.
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bool XHandlers::could_catch(ciInstanceKlass* klass, bool type_is_exact) const {
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// the type is unknown so be conservative
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if (!klass->is_loaded()) {
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return true;
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}
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for (int i = 0; i < length(); i++) {
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XHandler* handler = handler_at(i);
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if (handler->is_catch_all()) {
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// catch of ANY
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return true;
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}
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ciInstanceKlass* handler_klass = handler->catch_klass();
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// if it's unknown it might be catchable
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if (!handler_klass->is_loaded()) {
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return true;
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}
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// if the throw type is definitely a subtype of the catch type
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// then it can be caught.
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if (klass->is_subtype_of(handler_klass)) {
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return true;
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}
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if (!type_is_exact) {
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// If the type isn't exactly known then it can also be caught by
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// catch statements where the inexact type is a subtype of the
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// catch type.
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// given: foo extends bar extends Exception
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// throw bar can be caught by catch foo, catch bar, and catch
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// Exception, however it can't be caught by any handlers without
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// bar in its type hierarchy.
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if (handler_klass->is_subtype_of(klass)) {
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return true;
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}
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}
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}
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return false;
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}
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bool XHandlers::equals(XHandlers* others) const {
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if (others == NULL) return false;
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if (length() != others->length()) return false;
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for (int i = 0; i < length(); i++) {
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if (!handler_at(i)->equals(others->handler_at(i))) return false;
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}
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return true;
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}
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bool XHandler::equals(XHandler* other) const {
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assert(entry_pco() != -1 && other->entry_pco() != -1, "must have entry_pco");
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if (entry_pco() != other->entry_pco()) return false;
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if (scope_count() != other->scope_count()) return false;
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if (_desc != other->_desc) return false;
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assert(entry_block() == other->entry_block(), "entry_block must be equal when entry_pco is equal");
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return true;
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}
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// Implementation of IRScope
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BlockBegin* IRScope::header_block(BlockBegin* entry, BlockBegin::Flag f, ValueStack* state) {
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if (entry == NULL) return NULL;
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assert(entry->is_set(f), "entry/flag mismatch");
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// create header block
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BlockBegin* h = new BlockBegin(entry->bci());
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BlockEnd* g = new Goto(entry, false);
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h->set_next(g, entry->bci());
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h->set_end(g);
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h->set(f);
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// setup header block end state
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ValueStack* s = state->copy(); // can use copy since stack is empty (=> no phis)
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assert(s->stack_is_empty(), "must have empty stack at entry point");
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g->set_state(s);
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return h;
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}
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BlockBegin* IRScope::build_graph(Compilation* compilation, int osr_bci) {
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GraphBuilder gm(compilation, this);
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NOT_PRODUCT(if (PrintValueNumbering && Verbose) gm.print_stats());
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if (compilation->bailed_out()) return NULL;
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return gm.start();
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}
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IRScope::IRScope(Compilation* compilation, IRScope* caller, int caller_bci, ciMethod* method, int osr_bci, bool create_graph)
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: _callees(2)
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, _compilation(compilation)
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, _lock_stack_size(-1)
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, _requires_phi_function(method->max_locals())
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{
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_caller = caller;
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_caller_bci = caller == NULL ? -1 : caller_bci;
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_caller_state = NULL; // Must be set later if needed
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_level = caller == NULL ? 0 : caller->level() + 1;
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_method = method;
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_xhandlers = new XHandlers(method);
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_number_of_locks = 0;
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_monitor_pairing_ok = method->has_balanced_monitors();
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_start = NULL;
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if (osr_bci == -1) {
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_requires_phi_function.clear();
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} else {
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// selective creation of phi functions is not possibel in osr-methods
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_requires_phi_function.set_range(0, method->max_locals());
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}
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assert(method->holder()->is_loaded() , "method holder must be loaded");
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// build graph if monitor pairing is ok
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if (create_graph && monitor_pairing_ok()) _start = build_graph(compilation, osr_bci);
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}
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int IRScope::max_stack() const {
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int my_max = method()->max_stack();
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int callee_max = 0;
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for (int i = 0; i < number_of_callees(); i++) {
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callee_max = MAX2(callee_max, callee_no(i)->max_stack());
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}
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return my_max + callee_max;
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}
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void IRScope::compute_lock_stack_size() {
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if (!InlineMethodsWithExceptionHandlers) {
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_lock_stack_size = 0;
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return;
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}
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// Figure out whether we have to preserve expression stack elements
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// for parent scopes, and if so, how many
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IRScope* cur_scope = this;
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while (cur_scope != NULL && !cur_scope->xhandlers()->has_handlers()) {
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cur_scope = cur_scope->caller();
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}
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_lock_stack_size = (cur_scope == NULL ? 0 :
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(cur_scope->caller_state() == NULL ? 0 :
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cur_scope->caller_state()->stack_size()));
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}
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int IRScope::top_scope_bci() const {
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assert(!is_top_scope(), "no correct answer for top scope possible");
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const IRScope* scope = this;
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while (!scope->caller()->is_top_scope()) {
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scope = scope->caller();
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}
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return scope->caller_bci();
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}
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// Implementation of CodeEmitInfo
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// Stack must be NON-null
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CodeEmitInfo::CodeEmitInfo(int bci, ValueStack* stack, XHandlers* exception_handlers)
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: _scope(stack->scope())
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, _bci(bci)
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, _scope_debug_info(NULL)
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, _oop_map(NULL)
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, _stack(stack)
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, _exception_handlers(exception_handlers)
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, _next(NULL)
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, _id(-1) {
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assert(_stack != NULL, "must be non null");
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assert(_bci == SynchronizationEntryBCI || Bytecodes::is_defined(scope()->method()->java_code_at_bci(_bci)), "make sure bci points at a real bytecode");
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}
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CodeEmitInfo::CodeEmitInfo(CodeEmitInfo* info, bool lock_stack_only)
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: _scope(info->_scope)
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, _exception_handlers(NULL)
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, _bci(info->_bci)
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, _scope_debug_info(NULL)
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, _oop_map(NULL) {
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if (lock_stack_only) {
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if (info->_stack != NULL) {
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_stack = info->_stack->copy_locks();
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} else {
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_stack = NULL;
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}
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} else {
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_stack = info->_stack;
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}
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// deep copy of exception handlers
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if (info->_exception_handlers != NULL) {
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_exception_handlers = new XHandlers(info->_exception_handlers);
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}
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}
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void CodeEmitInfo::record_debug_info(DebugInformationRecorder* recorder, int pc_offset) {
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// record the safepoint before recording the debug info for enclosing scopes
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recorder->add_safepoint(pc_offset, _oop_map->deep_copy());
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_scope_debug_info->record_debug_info(recorder, pc_offset);
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recorder->end_safepoint(pc_offset);
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}
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void CodeEmitInfo::add_register_oop(LIR_Opr opr) {
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assert(_oop_map != NULL, "oop map must already exist");
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assert(opr->is_single_cpu(), "should not call otherwise");
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int frame_size = frame_map()->framesize();
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int arg_count = frame_map()->oop_map_arg_count();
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VMReg name = frame_map()->regname(opr);
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_oop_map->set_oop(name);
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}
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// Implementation of IR
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IR::IR(Compilation* compilation, ciMethod* method, int osr_bci) :
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_locals_size(in_WordSize(-1))
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, _num_loops(0) {
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// initialize data structures
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ValueType::initialize();
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Instruction::initialize();
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BlockBegin::initialize();
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GraphBuilder::initialize();
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// setup IR fields
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_compilation = compilation;
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_top_scope = new IRScope(compilation, NULL, -1, method, osr_bci, true);
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_code = NULL;
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}
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void IR::optimize() {
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Optimizer opt(this);
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if (DoCEE) {
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opt.eliminate_conditional_expressions();
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#ifndef PRODUCT
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if (PrintCFG || PrintCFG1) { tty->print_cr("CFG after CEE"); print(true); }
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if (PrintIR || PrintIR1 ) { tty->print_cr("IR after CEE"); print(false); }
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#endif
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}
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if (EliminateBlocks) {
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opt.eliminate_blocks();
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#ifndef PRODUCT
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if (PrintCFG || PrintCFG1) { tty->print_cr("CFG after block elimination"); print(true); }
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if (PrintIR || PrintIR1 ) { tty->print_cr("IR after block elimination"); print(false); }
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#endif
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}
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if (EliminateNullChecks) {
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opt.eliminate_null_checks();
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#ifndef PRODUCT
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if (PrintCFG || PrintCFG1) { tty->print_cr("CFG after null check elimination"); print(true); }
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if (PrintIR || PrintIR1 ) { tty->print_cr("IR after null check elimination"); print(false); }
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#endif
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}
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}
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static int sort_pairs(BlockPair** a, BlockPair** b) {
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if ((*a)->from() == (*b)->from()) {
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return (*a)->to()->block_id() - (*b)->to()->block_id();
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} else {
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return (*a)->from()->block_id() - (*b)->from()->block_id();
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}
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}
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class CriticalEdgeFinder: public BlockClosure {
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BlockPairList blocks;
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IR* _ir;
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public:
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CriticalEdgeFinder(IR* ir): _ir(ir) {}
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void block_do(BlockBegin* bb) {
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BlockEnd* be = bb->end();
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int nos = be->number_of_sux();
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if (nos >= 2) {
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for (int i = 0; i < nos; i++) {
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BlockBegin* sux = be->sux_at(i);
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if (sux->number_of_preds() >= 2) {
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blocks.append(new BlockPair(bb, sux));
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}
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}
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}
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}
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void split_edges() {
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BlockPair* last_pair = NULL;
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blocks.sort(sort_pairs);
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for (int i = 0; i < blocks.length(); i++) {
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BlockPair* pair = blocks.at(i);
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if (last_pair != NULL && pair->is_same(last_pair)) continue;
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BlockBegin* from = pair->from();
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BlockBegin* to = pair->to();
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BlockBegin* split = from->insert_block_between(to);
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#ifndef PRODUCT
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if ((PrintIR || PrintIR1) && Verbose) {
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tty->print_cr("Split critical edge B%d -> B%d (new block B%d)",
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from->block_id(), to->block_id(), split->block_id());
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}
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#endif
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last_pair = pair;
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}
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}
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};
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void IR::split_critical_edges() {
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CriticalEdgeFinder cef(this);
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iterate_preorder(&cef);
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cef.split_edges();
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}
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class UseCountComputer: public AllStatic {
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private:
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static void update_use_count(Value* n) {
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// Local instructions and Phis for expression stack values at the
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// start of basic blocks are not added to the instruction list
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if ((*n)->bci() == -99 && (*n)->as_Local() == NULL &&
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(*n)->as_Phi() == NULL) {
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assert(false, "a node was not appended to the graph");
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Compilation::current_compilation()->bailout("a node was not appended to the graph");
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}
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// use n's input if not visited before
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if (!(*n)->is_pinned() && !(*n)->has_uses()) {
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// note: a) if the instruction is pinned, it will be handled by compute_use_count
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// b) if the instruction has uses, it was touched before
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// => in both cases we don't need to update n's values
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uses_do(n);
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}
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// use n
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(*n)->_use_count++;
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}
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static Values* worklist;
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static int depth;
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enum {
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max_recurse_depth = 20
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};
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static void uses_do(Value* n) {
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depth++;
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if (depth > max_recurse_depth) {
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// don't allow the traversal to recurse too deeply
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worklist->push(*n);
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} else {
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|
406 |
(*n)->input_values_do(update_use_count);
|
|
407 |
// special handling for some instructions
|
|
408 |
if ((*n)->as_BlockEnd() != NULL) {
|
|
409 |
// note on BlockEnd:
|
|
410 |
// must 'use' the stack only if the method doesn't
|
|
411 |
// terminate, however, in those cases stack is empty
|
|
412 |
(*n)->state_values_do(update_use_count);
|
|
413 |
}
|
|
414 |
}
|
|
415 |
depth--;
|
|
416 |
}
|
|
417 |
|
|
418 |
static void basic_compute_use_count(BlockBegin* b) {
|
|
419 |
depth = 0;
|
|
420 |
// process all pinned nodes as the roots of expression trees
|
|
421 |
for (Instruction* n = b; n != NULL; n = n->next()) {
|
|
422 |
if (n->is_pinned()) uses_do(&n);
|
|
423 |
}
|
|
424 |
assert(depth == 0, "should have counted back down");
|
|
425 |
|
|
426 |
// now process any unpinned nodes which recursed too deeply
|
|
427 |
while (worklist->length() > 0) {
|
|
428 |
Value t = worklist->pop();
|
|
429 |
if (!t->is_pinned()) {
|
|
430 |
// compute the use count
|
|
431 |
uses_do(&t);
|
|
432 |
|
|
433 |
// pin the instruction so that LIRGenerator doesn't recurse
|
|
434 |
// too deeply during it's evaluation.
|
|
435 |
t->pin();
|
|
436 |
}
|
|
437 |
}
|
|
438 |
assert(depth == 0, "should have counted back down");
|
|
439 |
}
|
|
440 |
|
|
441 |
public:
|
|
442 |
static void compute(BlockList* blocks) {
|
|
443 |
worklist = new Values();
|
|
444 |
blocks->blocks_do(basic_compute_use_count);
|
|
445 |
worklist = NULL;
|
|
446 |
}
|
|
447 |
};
|
|
448 |
|
|
449 |
|
|
450 |
Values* UseCountComputer::worklist = NULL;
|
|
451 |
int UseCountComputer::depth = 0;
|
|
452 |
|
|
453 |
// helper macro for short definition of trace-output inside code
|
|
454 |
#ifndef PRODUCT
|
|
455 |
#define TRACE_LINEAR_SCAN(level, code) \
|
|
456 |
if (TraceLinearScanLevel >= level) { \
|
|
457 |
code; \
|
|
458 |
}
|
|
459 |
#else
|
|
460 |
#define TRACE_LINEAR_SCAN(level, code)
|
|
461 |
#endif
|
|
462 |
|
|
463 |
class ComputeLinearScanOrder : public StackObj {
|
|
464 |
private:
|
|
465 |
int _max_block_id; // the highest block_id of a block
|
|
466 |
int _num_blocks; // total number of blocks (smaller than _max_block_id)
|
|
467 |
int _num_loops; // total number of loops
|
|
468 |
bool _iterative_dominators;// method requires iterative computation of dominatiors
|
|
469 |
|
|
470 |
BlockList* _linear_scan_order; // the resulting list of blocks in correct order
|
|
471 |
|
|
472 |
BitMap _visited_blocks; // used for recursive processing of blocks
|
|
473 |
BitMap _active_blocks; // used for recursive processing of blocks
|
|
474 |
BitMap _dominator_blocks; // temproary BitMap used for computation of dominator
|
|
475 |
intArray _forward_branches; // number of incoming forward branches for each block
|
|
476 |
BlockList _loop_end_blocks; // list of all loop end blocks collected during count_edges
|
|
477 |
BitMap2D _loop_map; // two-dimensional bit set: a bit is set if a block is contained in a loop
|
|
478 |
BlockList _work_list; // temporary list (used in mark_loops and compute_order)
|
|
479 |
|
|
480 |
// accessors for _visited_blocks and _active_blocks
|
|
481 |
void init_visited() { _active_blocks.clear(); _visited_blocks.clear(); }
|
|
482 |
bool is_visited(BlockBegin* b) const { return _visited_blocks.at(b->block_id()); }
|
|
483 |
bool is_active(BlockBegin* b) const { return _active_blocks.at(b->block_id()); }
|
|
484 |
void set_visited(BlockBegin* b) { assert(!is_visited(b), "already set"); _visited_blocks.set_bit(b->block_id()); }
|
|
485 |
void set_active(BlockBegin* b) { assert(!is_active(b), "already set"); _active_blocks.set_bit(b->block_id()); }
|
|
486 |
void clear_active(BlockBegin* b) { assert(is_active(b), "not already"); _active_blocks.clear_bit(b->block_id()); }
|
|
487 |
|
|
488 |
// accessors for _forward_branches
|
|
489 |
void inc_forward_branches(BlockBegin* b) { _forward_branches.at_put(b->block_id(), _forward_branches.at(b->block_id()) + 1); }
|
|
490 |
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()); }
|
|
491 |
|
|
492 |
// accessors for _loop_map
|
|
493 |
bool is_block_in_loop (int loop_idx, BlockBegin* b) const { return _loop_map.at(loop_idx, b->block_id()); }
|
|
494 |
void set_block_in_loop (int loop_idx, BlockBegin* b) { _loop_map.set_bit(loop_idx, b->block_id()); }
|
|
495 |
void clear_block_in_loop(int loop_idx, int block_id) { _loop_map.clear_bit(loop_idx, block_id); }
|
|
496 |
|
|
497 |
// count edges between blocks
|
|
498 |
void count_edges(BlockBegin* cur, BlockBegin* parent);
|
|
499 |
|
|
500 |
// loop detection
|
|
501 |
void mark_loops();
|
|
502 |
void clear_non_natural_loops(BlockBegin* start_block);
|
|
503 |
void assign_loop_depth(BlockBegin* start_block);
|
|
504 |
|
|
505 |
// computation of final block order
|
|
506 |
BlockBegin* common_dominator(BlockBegin* a, BlockBegin* b);
|
|
507 |
void compute_dominator(BlockBegin* cur, BlockBegin* parent);
|
|
508 |
int compute_weight(BlockBegin* cur);
|
|
509 |
bool ready_for_processing(BlockBegin* cur);
|
|
510 |
void sort_into_work_list(BlockBegin* b);
|
|
511 |
void append_block(BlockBegin* cur);
|
|
512 |
void compute_order(BlockBegin* start_block);
|
|
513 |
|
|
514 |
// fixup of dominators for non-natural loops
|
|
515 |
bool compute_dominators_iter();
|
|
516 |
void compute_dominators();
|
|
517 |
|
|
518 |
// debug functions
|
|
519 |
NOT_PRODUCT(void print_blocks();)
|
|
520 |
DEBUG_ONLY(void verify();)
|
|
521 |
|
|
522 |
public:
|
|
523 |
ComputeLinearScanOrder(BlockBegin* start_block);
|
|
524 |
|
|
525 |
// accessors for final result
|
|
526 |
BlockList* linear_scan_order() const { return _linear_scan_order; }
|
|
527 |
int num_loops() const { return _num_loops; }
|
|
528 |
};
|
|
529 |
|
|
530 |
|
|
531 |
ComputeLinearScanOrder::ComputeLinearScanOrder(BlockBegin* start_block) :
|
|
532 |
_max_block_id(BlockBegin::number_of_blocks()),
|
|
533 |
_num_blocks(0),
|
|
534 |
_num_loops(0),
|
|
535 |
_iterative_dominators(false),
|
|
536 |
_visited_blocks(_max_block_id),
|
|
537 |
_active_blocks(_max_block_id),
|
|
538 |
_dominator_blocks(_max_block_id),
|
|
539 |
_forward_branches(_max_block_id, 0),
|
|
540 |
_loop_end_blocks(8),
|
|
541 |
_work_list(8),
|
|
542 |
_linear_scan_order(NULL), // initialized later with correct size
|
|
543 |
_loop_map(0, 0) // initialized later with correct size
|
|
544 |
{
|
|
545 |
TRACE_LINEAR_SCAN(2, "***** computing linear-scan block order");
|
|
546 |
|
|
547 |
init_visited();
|
|
548 |
count_edges(start_block, NULL);
|
|
549 |
|
|
550 |
if (_num_loops > 0) {
|
|
551 |
mark_loops();
|
|
552 |
clear_non_natural_loops(start_block);
|
|
553 |
assign_loop_depth(start_block);
|
|
554 |
}
|
|
555 |
|
|
556 |
compute_order(start_block);
|
|
557 |
compute_dominators();
|
|
558 |
|
|
559 |
NOT_PRODUCT(print_blocks());
|
|
560 |
DEBUG_ONLY(verify());
|
|
561 |
}
|
|
562 |
|
|
563 |
|
|
564 |
// Traverse the CFG:
|
|
565 |
// * count total number of blocks
|
|
566 |
// * count all incoming edges and backward incoming edges
|
|
567 |
// * number loop header blocks
|
|
568 |
// * create a list with all loop end blocks
|
|
569 |
void ComputeLinearScanOrder::count_edges(BlockBegin* cur, BlockBegin* parent) {
|
|
570 |
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));
|
|
571 |
assert(cur->dominator() == NULL, "dominator already initialized");
|
|
572 |
|
|
573 |
if (is_active(cur)) {
|
|
574 |
TRACE_LINEAR_SCAN(3, tty->print_cr("backward branch"));
|
|
575 |
assert(is_visited(cur), "block must be visisted when block is active");
|
|
576 |
assert(parent != NULL, "must have parent");
|
|
577 |
assert(parent->number_of_sux() == 1, "loop end blocks must have one successor (critical edges are split)");
|
|
578 |
|
|
579 |
cur->set(BlockBegin::linear_scan_loop_header_flag);
|
|
580 |
cur->set(BlockBegin::backward_branch_target_flag);
|
|
581 |
|
|
582 |
parent->set(BlockBegin::linear_scan_loop_end_flag);
|
|
583 |
_loop_end_blocks.append(parent);
|
|
584 |
return;
|
|
585 |
}
|
|
586 |
|
|
587 |
// increment number of incoming forward branches
|
|
588 |
inc_forward_branches(cur);
|
|
589 |
|
|
590 |
if (is_visited(cur)) {
|
|
591 |
TRACE_LINEAR_SCAN(3, tty->print_cr("block already visited"));
|
|
592 |
return;
|
|
593 |
}
|
|
594 |
|
|
595 |
_num_blocks++;
|
|
596 |
set_visited(cur);
|
|
597 |
set_active(cur);
|
|
598 |
|
|
599 |
// recursive call for all successors
|
|
600 |
int i;
|
|
601 |
for (i = cur->number_of_sux() - 1; i >= 0; i--) {
|
|
602 |
count_edges(cur->sux_at(i), cur);
|
|
603 |
}
|
|
604 |
for (i = cur->number_of_exception_handlers() - 1; i >= 0; i--) {
|
|
605 |
count_edges(cur->exception_handler_at(i), cur);
|
|
606 |
}
|
|
607 |
|
|
608 |
clear_active(cur);
|
|
609 |
|
|
610 |
// Each loop has a unique number.
|
|
611 |
// When multiple loops are nested, assign_loop_depth assumes that the
|
|
612 |
// innermost loop has the lowest number. This is guaranteed by setting
|
|
613 |
// the loop number after the recursive calls for the successors above
|
|
614 |
// have returned.
|
|
615 |
if (cur->is_set(BlockBegin::linear_scan_loop_header_flag)) {
|
|
616 |
assert(cur->loop_index() == -1, "cannot set loop-index twice");
|
|
617 |
TRACE_LINEAR_SCAN(3, tty->print_cr("Block B%d is loop header of loop %d", cur->block_id(), _num_loops));
|
|
618 |
|
|
619 |
cur->set_loop_index(_num_loops);
|
|
620 |
_num_loops++;
|
|
621 |
}
|
|
622 |
|
|
623 |
TRACE_LINEAR_SCAN(3, tty->print_cr("Finished count_edges for block B%d", cur->block_id()));
|
|
624 |
}
|
|
625 |
|
|
626 |
|
|
627 |
void ComputeLinearScanOrder::mark_loops() {
|
|
628 |
TRACE_LINEAR_SCAN(3, tty->print_cr("----- marking loops"));
|
|
629 |
|
|
630 |
_loop_map = BitMap2D(_num_loops, _max_block_id);
|
|
631 |
_loop_map.clear();
|
|
632 |
|
|
633 |
for (int i = _loop_end_blocks.length() - 1; i >= 0; i--) {
|
|
634 |
BlockBegin* loop_end = _loop_end_blocks.at(i);
|
|
635 |
BlockBegin* loop_start = loop_end->sux_at(0);
|
|
636 |
int loop_idx = loop_start->loop_index();
|
|
637 |
|
|
638 |
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));
|
|
639 |
assert(loop_end->is_set(BlockBegin::linear_scan_loop_end_flag), "loop end flag must be set");
|
|
640 |
assert(loop_end->number_of_sux() == 1, "incorrect number of successors");
|
|
641 |
assert(loop_start->is_set(BlockBegin::linear_scan_loop_header_flag), "loop header flag must be set");
|
|
642 |
assert(loop_idx >= 0 && loop_idx < _num_loops, "loop index not set");
|
|
643 |
assert(_work_list.is_empty(), "work list must be empty before processing");
|
|
644 |
|
|
645 |
// add the end-block of the loop to the working list
|
|
646 |
_work_list.push(loop_end);
|
|
647 |
set_block_in_loop(loop_idx, loop_end);
|
|
648 |
do {
|
|
649 |
BlockBegin* cur = _work_list.pop();
|
|
650 |
|
|
651 |
TRACE_LINEAR_SCAN(3, tty->print_cr(" processing B%d", cur->block_id()));
|
|
652 |
assert(is_block_in_loop(loop_idx, cur), "bit in loop map must be set when block is in work list");
|
|
653 |
|
|
654 |
// recursive processing of all predecessors ends when start block of loop is reached
|
|
655 |
if (cur != loop_start && !cur->is_set(BlockBegin::osr_entry_flag)) {
|
|
656 |
for (int j = cur->number_of_preds() - 1; j >= 0; j--) {
|
|
657 |
BlockBegin* pred = cur->pred_at(j);
|
|
658 |
|
|
659 |
if (!is_block_in_loop(loop_idx, pred) /*&& !pred->is_set(BlockBeginosr_entry_flag)*/) {
|
|
660 |
// this predecessor has not been processed yet, so add it to work list
|
|
661 |
TRACE_LINEAR_SCAN(3, tty->print_cr(" pushing B%d", pred->block_id()));
|
|
662 |
_work_list.push(pred);
|
|
663 |
set_block_in_loop(loop_idx, pred);
|
|
664 |
}
|
|
665 |
}
|
|
666 |
}
|
|
667 |
} while (!_work_list.is_empty());
|
|
668 |
}
|
|
669 |
}
|
|
670 |
|
|
671 |
|
|
672 |
// check for non-natural loops (loops where the loop header does not dominate
|
|
673 |
// all other loop blocks = loops with mulitple entries).
|
|
674 |
// such loops are ignored
|
|
675 |
void ComputeLinearScanOrder::clear_non_natural_loops(BlockBegin* start_block) {
|
|
676 |
for (int i = _num_loops - 1; i >= 0; i--) {
|
|
677 |
if (is_block_in_loop(i, start_block)) {
|
|
678 |
// loop i contains the entry block of the method
|
|
679 |
// -> this is not a natural loop, so ignore it
|
|
680 |
TRACE_LINEAR_SCAN(2, tty->print_cr("Loop %d is non-natural, so it is ignored", i));
|
|
681 |
|
|
682 |
for (int block_id = _max_block_id - 1; block_id >= 0; block_id--) {
|
|
683 |
clear_block_in_loop(i, block_id);
|
|
684 |
}
|
|
685 |
_iterative_dominators = true;
|
|
686 |
}
|
|
687 |
}
|
|
688 |
}
|
|
689 |
|
|
690 |
void ComputeLinearScanOrder::assign_loop_depth(BlockBegin* start_block) {
|
|
691 |
TRACE_LINEAR_SCAN(3, "----- computing loop-depth and weight");
|
|
692 |
init_visited();
|
|
693 |
|
|
694 |
assert(_work_list.is_empty(), "work list must be empty before processing");
|
|
695 |
_work_list.append(start_block);
|
|
696 |
|
|
697 |
do {
|
|
698 |
BlockBegin* cur = _work_list.pop();
|
|
699 |
|
|
700 |
if (!is_visited(cur)) {
|
|
701 |
set_visited(cur);
|
|
702 |
TRACE_LINEAR_SCAN(4, tty->print_cr("Computing loop depth for block B%d", cur->block_id()));
|
|
703 |
|
|
704 |
// compute loop-depth and loop-index for the block
|
|
705 |
assert(cur->loop_depth() == 0, "cannot set loop-depth twice");
|
|
706 |
int i;
|
|
707 |
int loop_depth = 0;
|
|
708 |
int min_loop_idx = -1;
|
|
709 |
for (i = _num_loops - 1; i >= 0; i--) {
|
|
710 |
if (is_block_in_loop(i, cur)) {
|
|
711 |
loop_depth++;
|
|
712 |
min_loop_idx = i;
|
|
713 |
}
|
|
714 |
}
|
|
715 |
cur->set_loop_depth(loop_depth);
|
|
716 |
cur->set_loop_index(min_loop_idx);
|
|
717 |
|
|
718 |
// append all unvisited successors to work list
|
|
719 |
for (i = cur->number_of_sux() - 1; i >= 0; i--) {
|
|
720 |
_work_list.append(cur->sux_at(i));
|
|
721 |
}
|
|
722 |
for (i = cur->number_of_exception_handlers() - 1; i >= 0; i--) {
|
|
723 |
_work_list.append(cur->exception_handler_at(i));
|
|
724 |
}
|
|
725 |
}
|
|
726 |
} while (!_work_list.is_empty());
|
|
727 |
}
|
|
728 |
|
|
729 |
|
|
730 |
BlockBegin* ComputeLinearScanOrder::common_dominator(BlockBegin* a, BlockBegin* b) {
|
|
731 |
assert(a != NULL && b != NULL, "must have input blocks");
|
|
732 |
|
|
733 |
_dominator_blocks.clear();
|
|
734 |
while (a != NULL) {
|
|
735 |
_dominator_blocks.set_bit(a->block_id());
|
|
736 |
assert(a->dominator() != NULL || a == _linear_scan_order->at(0), "dominator must be initialized");
|
|
737 |
a = a->dominator();
|
|
738 |
}
|
|
739 |
while (b != NULL && !_dominator_blocks.at(b->block_id())) {
|
|
740 |
assert(b->dominator() != NULL || b == _linear_scan_order->at(0), "dominator must be initialized");
|
|
741 |
b = b->dominator();
|
|
742 |
}
|
|
743 |
|
|
744 |
assert(b != NULL, "could not find dominator");
|
|
745 |
return b;
|
|
746 |
}
|
|
747 |
|
|
748 |
void ComputeLinearScanOrder::compute_dominator(BlockBegin* cur, BlockBegin* parent) {
|
|
749 |
if (cur->dominator() == NULL) {
|
|
750 |
TRACE_LINEAR_SCAN(4, tty->print_cr("DOM: initializing dominator of B%d to B%d", cur->block_id(), parent->block_id()));
|
|
751 |
cur->set_dominator(parent);
|
|
752 |
|
|
753 |
} else if (!(cur->is_set(BlockBegin::linear_scan_loop_header_flag) && parent->is_set(BlockBegin::linear_scan_loop_end_flag))) {
|
|
754 |
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()));
|
|
755 |
assert(cur->number_of_preds() > 1, "");
|
|
756 |
cur->set_dominator(common_dominator(cur->dominator(), parent));
|
|
757 |
}
|
|
758 |
}
|
|
759 |
|
|
760 |
|
|
761 |
int ComputeLinearScanOrder::compute_weight(BlockBegin* cur) {
|
|
762 |
BlockBegin* single_sux = NULL;
|
|
763 |
if (cur->number_of_sux() == 1) {
|
|
764 |
single_sux = cur->sux_at(0);
|
|
765 |
}
|
|
766 |
|
|
767 |
// limit loop-depth to 15 bit (only for security reason, it will never be so big)
|
|
768 |
int weight = (cur->loop_depth() & 0x7FFF) << 16;
|
|
769 |
|
|
770 |
// general macro for short definition of weight flags
|
|
771 |
// the first instance of INC_WEIGHT_IF has the highest priority
|
|
772 |
int cur_bit = 15;
|
|
773 |
#define INC_WEIGHT_IF(condition) if ((condition)) { weight |= (1 << cur_bit); } cur_bit--;
|
|
774 |
|
|
775 |
// this is necessery for the (very rare) case that two successing blocks have
|
|
776 |
// the same loop depth, but a different loop index (can happen for endless loops
|
|
777 |
// with exception handlers)
|
|
778 |
INC_WEIGHT_IF(!cur->is_set(BlockBegin::linear_scan_loop_header_flag));
|
|
779 |
|
|
780 |
// loop end blocks (blocks that end with a backward branch) are added
|
|
781 |
// after all other blocks of the loop.
|
|
782 |
INC_WEIGHT_IF(!cur->is_set(BlockBegin::linear_scan_loop_end_flag));
|
|
783 |
|
|
784 |
// critical edge split blocks are prefered because than they have a bigger
|
|
785 |
// proability to be completely empty
|
|
786 |
INC_WEIGHT_IF(cur->is_set(BlockBegin::critical_edge_split_flag));
|
|
787 |
|
|
788 |
// exceptions should not be thrown in normal control flow, so these blocks
|
|
789 |
// are added as late as possible
|
|
790 |
INC_WEIGHT_IF(cur->end()->as_Throw() == NULL && (single_sux == NULL || single_sux->end()->as_Throw() == NULL));
|
|
791 |
INC_WEIGHT_IF(cur->end()->as_Return() == NULL && (single_sux == NULL || single_sux->end()->as_Return() == NULL));
|
|
792 |
|
|
793 |
// exceptions handlers are added as late as possible
|
|
794 |
INC_WEIGHT_IF(!cur->is_set(BlockBegin::exception_entry_flag));
|
|
795 |
|
|
796 |
// guarantee that weight is > 0
|
|
797 |
weight |= 1;
|
|
798 |
|
|
799 |
#undef INC_WEIGHT_IF
|
|
800 |
assert(cur_bit >= 0, "too many flags");
|
|
801 |
assert(weight > 0, "weight cannot become negative");
|
|
802 |
|
|
803 |
return weight;
|
|
804 |
}
|
|
805 |
|
|
806 |
bool ComputeLinearScanOrder::ready_for_processing(BlockBegin* cur) {
|
|
807 |
// Discount the edge just traveled.
|
|
808 |
// When the number drops to zero, all forward branches were processed
|
|
809 |
if (dec_forward_branches(cur) != 0) {
|
|
810 |
return false;
|
|
811 |
}
|
|
812 |
|
|
813 |
assert(_linear_scan_order->index_of(cur) == -1, "block already processed (block can be ready only once)");
|
|
814 |
assert(_work_list.index_of(cur) == -1, "block already in work-list (block can be ready only once)");
|
|
815 |
return true;
|
|
816 |
}
|
|
817 |
|
|
818 |
void ComputeLinearScanOrder::sort_into_work_list(BlockBegin* cur) {
|
|
819 |
assert(_work_list.index_of(cur) == -1, "block already in work list");
|
|
820 |
|
|
821 |
int cur_weight = compute_weight(cur);
|
|
822 |
|
|
823 |
// the linear_scan_number is used to cache the weight of a block
|
|
824 |
cur->set_linear_scan_number(cur_weight);
|
|
825 |
|
|
826 |
#ifndef PRODUCT
|
|
827 |
if (StressLinearScan) {
|
|
828 |
_work_list.insert_before(0, cur);
|
|
829 |
return;
|
|
830 |
}
|
|
831 |
#endif
|
|
832 |
|
|
833 |
_work_list.append(NULL); // provide space for new element
|
|
834 |
|
|
835 |
int insert_idx = _work_list.length() - 1;
|
|
836 |
while (insert_idx > 0 && _work_list.at(insert_idx - 1)->linear_scan_number() > cur_weight) {
|
|
837 |
_work_list.at_put(insert_idx, _work_list.at(insert_idx - 1));
|
|
838 |
insert_idx--;
|
|
839 |
}
|
|
840 |
_work_list.at_put(insert_idx, cur);
|
|
841 |
|
|
842 |
TRACE_LINEAR_SCAN(3, tty->print_cr("Sorted B%d into worklist. new worklist:", cur->block_id()));
|
|
843 |
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()));
|
|
844 |
|
|
845 |
#ifdef ASSERT
|
|
846 |
for (int i = 0; i < _work_list.length(); i++) {
|
|
847 |
assert(_work_list.at(i)->linear_scan_number() > 0, "weight not set");
|
|
848 |
assert(i == 0 || _work_list.at(i - 1)->linear_scan_number() <= _work_list.at(i)->linear_scan_number(), "incorrect order in worklist");
|
|
849 |
}
|
|
850 |
#endif
|
|
851 |
}
|
|
852 |
|
|
853 |
void ComputeLinearScanOrder::append_block(BlockBegin* cur) {
|
|
854 |
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()));
|
|
855 |
assert(_linear_scan_order->index_of(cur) == -1, "cannot add the same block twice");
|
|
856 |
|
|
857 |
// currently, the linear scan order and code emit order are equal.
|
|
858 |
// therefore the linear_scan_number and the weight of a block must also
|
|
859 |
// be equal.
|
|
860 |
cur->set_linear_scan_number(_linear_scan_order->length());
|
|
861 |
_linear_scan_order->append(cur);
|
|
862 |
}
|
|
863 |
|
|
864 |
void ComputeLinearScanOrder::compute_order(BlockBegin* start_block) {
|
|
865 |
TRACE_LINEAR_SCAN(3, "----- computing final block order");
|
|
866 |
|
|
867 |
// the start block is always the first block in the linear scan order
|
|
868 |
_linear_scan_order = new BlockList(_num_blocks);
|
|
869 |
append_block(start_block);
|
|
870 |
|
|
871 |
assert(start_block->end()->as_Base() != NULL, "start block must end with Base-instruction");
|
|
872 |
BlockBegin* std_entry = ((Base*)start_block->end())->std_entry();
|
|
873 |
BlockBegin* osr_entry = ((Base*)start_block->end())->osr_entry();
|
|
874 |
|
|
875 |
BlockBegin* sux_of_osr_entry = NULL;
|
|
876 |
if (osr_entry != NULL) {
|
|
877 |
// special handling for osr entry:
|
|
878 |
// ignore the edge between the osr entry and its successor for processing
|
|
879 |
// the osr entry block is added manually below
|
|
880 |
assert(osr_entry->number_of_sux() == 1, "osr entry must have exactly one successor");
|
|
881 |
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");
|
|
882 |
|
|
883 |
sux_of_osr_entry = osr_entry->sux_at(0);
|
|
884 |
dec_forward_branches(sux_of_osr_entry);
|
|
885 |
|
|
886 |
compute_dominator(osr_entry, start_block);
|
|
887 |
_iterative_dominators = true;
|
|
888 |
}
|
|
889 |
compute_dominator(std_entry, start_block);
|
|
890 |
|
|
891 |
// start processing with standard entry block
|
|
892 |
assert(_work_list.is_empty(), "list must be empty before processing");
|
|
893 |
|
|
894 |
if (ready_for_processing(std_entry)) {
|
|
895 |
sort_into_work_list(std_entry);
|
|
896 |
} else {
|
|
897 |
assert(false, "the std_entry must be ready for processing (otherwise, the method has no start block)");
|
|
898 |
}
|
|
899 |
|
|
900 |
do {
|
|
901 |
BlockBegin* cur = _work_list.pop();
|
|
902 |
|
|
903 |
if (cur == sux_of_osr_entry) {
|
|
904 |
// the osr entry block is ignored in normal processing, it is never added to the
|
|
905 |
// work list. Instead, it is added as late as possible manually here.
|
|
906 |
append_block(osr_entry);
|
|
907 |
compute_dominator(cur, osr_entry);
|
|
908 |
}
|
|
909 |
append_block(cur);
|
|
910 |
|
|
911 |
int i;
|
|
912 |
int num_sux = cur->number_of_sux();
|
|
913 |
// changed loop order to get "intuitive" order of if- and else-blocks
|
|
914 |
for (i = 0; i < num_sux; i++) {
|
|
915 |
BlockBegin* sux = cur->sux_at(i);
|
|
916 |
compute_dominator(sux, cur);
|
|
917 |
if (ready_for_processing(sux)) {
|
|
918 |
sort_into_work_list(sux);
|
|
919 |
}
|
|
920 |
}
|
|
921 |
num_sux = cur->number_of_exception_handlers();
|
|
922 |
for (i = 0; i < num_sux; i++) {
|
|
923 |
BlockBegin* sux = cur->exception_handler_at(i);
|
|
924 |
compute_dominator(sux, cur);
|
|
925 |
if (ready_for_processing(sux)) {
|
|
926 |
sort_into_work_list(sux);
|
|
927 |
}
|
|
928 |
}
|
|
929 |
} while (_work_list.length() > 0);
|
|
930 |
}
|
|
931 |
|
|
932 |
|
|
933 |
bool ComputeLinearScanOrder::compute_dominators_iter() {
|
|
934 |
bool changed = false;
|
|
935 |
int num_blocks = _linear_scan_order->length();
|
|
936 |
|
|
937 |
assert(_linear_scan_order->at(0)->dominator() == NULL, "must not have dominator");
|
|
938 |
assert(_linear_scan_order->at(0)->number_of_preds() == 0, "must not have predecessors");
|
|
939 |
for (int i = 1; i < num_blocks; i++) {
|
|
940 |
BlockBegin* block = _linear_scan_order->at(i);
|
|
941 |
|
|
942 |
BlockBegin* dominator = block->pred_at(0);
|
|
943 |
int num_preds = block->number_of_preds();
|
|
944 |
for (int i = 1; i < num_preds; i++) {
|
|
945 |
dominator = common_dominator(dominator, block->pred_at(i));
|
|
946 |
}
|
|
947 |
|
|
948 |
if (dominator != block->dominator()) {
|
|
949 |
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()));
|
|
950 |
|
|
951 |
block->set_dominator(dominator);
|
|
952 |
changed = true;
|
|
953 |
}
|
|
954 |
}
|
|
955 |
return changed;
|
|
956 |
}
|
|
957 |
|
|
958 |
void ComputeLinearScanOrder::compute_dominators() {
|
|
959 |
TRACE_LINEAR_SCAN(3, tty->print_cr("----- computing dominators (iterative computation reqired: %d)", _iterative_dominators));
|
|
960 |
|
|
961 |
// iterative computation of dominators is only required for methods with non-natural loops
|
|
962 |
// and OSR-methods. For all other methods, the dominators computed when generating the
|
|
963 |
// linear scan block order are correct.
|
|
964 |
if (_iterative_dominators) {
|
|
965 |
do {
|
|
966 |
TRACE_LINEAR_SCAN(1, tty->print_cr("DOM: next iteration of fix-point calculation"));
|
|
967 |
} while (compute_dominators_iter());
|
|
968 |
}
|
|
969 |
|
|
970 |
// check that dominators are correct
|
|
971 |
assert(!compute_dominators_iter(), "fix point not reached");
|
|
972 |
}
|
|
973 |
|
|
974 |
|
|
975 |
#ifndef PRODUCT
|
|
976 |
void ComputeLinearScanOrder::print_blocks() {
|
|
977 |
if (TraceLinearScanLevel >= 2) {
|
|
978 |
tty->print_cr("----- loop information:");
|
|
979 |
for (int block_idx = 0; block_idx < _linear_scan_order->length(); block_idx++) {
|
|
980 |
BlockBegin* cur = _linear_scan_order->at(block_idx);
|
|
981 |
|
|
982 |
tty->print("%4d: B%2d: ", cur->linear_scan_number(), cur->block_id());
|
|
983 |
for (int loop_idx = 0; loop_idx < _num_loops; loop_idx++) {
|
|
984 |
tty->print ("%d ", is_block_in_loop(loop_idx, cur));
|
|
985 |
}
|
|
986 |
tty->print_cr(" -> loop_index: %2d, loop_depth: %2d", cur->loop_index(), cur->loop_depth());
|
|
987 |
}
|
|
988 |
}
|
|
989 |
|
|
990 |
if (TraceLinearScanLevel >= 1) {
|
|
991 |
tty->print_cr("----- linear-scan block order:");
|
|
992 |
for (int block_idx = 0; block_idx < _linear_scan_order->length(); block_idx++) {
|
|
993 |
BlockBegin* cur = _linear_scan_order->at(block_idx);
|
|
994 |
tty->print("%4d: B%2d loop: %2d depth: %2d", cur->linear_scan_number(), cur->block_id(), cur->loop_index(), cur->loop_depth());
|
|
995 |
|
|
996 |
tty->print(cur->is_set(BlockBegin::exception_entry_flag) ? " ex" : " ");
|
|
997 |
tty->print(cur->is_set(BlockBegin::critical_edge_split_flag) ? " ce" : " ");
|
|
998 |
tty->print(cur->is_set(BlockBegin::linear_scan_loop_header_flag) ? " lh" : " ");
|
|
999 |
tty->print(cur->is_set(BlockBegin::linear_scan_loop_end_flag) ? " le" : " ");
|
|
1000 |
|
|
1001 |
if (cur->dominator() != NULL) {
|
|
1002 |
tty->print(" dom: B%d ", cur->dominator()->block_id());
|
|
1003 |
} else {
|
|
1004 |
tty->print(" dom: NULL ");
|
|
1005 |
}
|
|
1006 |
|
|
1007 |
if (cur->number_of_preds() > 0) {
|
|
1008 |
tty->print(" preds: ");
|
|
1009 |
for (int j = 0; j < cur->number_of_preds(); j++) {
|
|
1010 |
BlockBegin* pred = cur->pred_at(j);
|
|
1011 |
tty->print("B%d ", pred->block_id());
|
|
1012 |
}
|
|
1013 |
}
|
|
1014 |
if (cur->number_of_sux() > 0) {
|
|
1015 |
tty->print(" sux: ");
|
|
1016 |
for (int j = 0; j < cur->number_of_sux(); j++) {
|
|
1017 |
BlockBegin* sux = cur->sux_at(j);
|
|
1018 |
tty->print("B%d ", sux->block_id());
|
|
1019 |
}
|
|
1020 |
}
|
|
1021 |
if (cur->number_of_exception_handlers() > 0) {
|
|
1022 |
tty->print(" ex: ");
|
|
1023 |
for (int j = 0; j < cur->number_of_exception_handlers(); j++) {
|
|
1024 |
BlockBegin* ex = cur->exception_handler_at(j);
|
|
1025 |
tty->print("B%d ", ex->block_id());
|
|
1026 |
}
|
|
1027 |
}
|
|
1028 |
tty->cr();
|
|
1029 |
}
|
|
1030 |
}
|
|
1031 |
}
|
|
1032 |
#endif
|
|
1033 |
|
|
1034 |
#ifdef ASSERT
|
|
1035 |
void ComputeLinearScanOrder::verify() {
|
|
1036 |
assert(_linear_scan_order->length() == _num_blocks, "wrong number of blocks in list");
|
|
1037 |
|
|
1038 |
if (StressLinearScan) {
|
|
1039 |
// blocks are scrambled when StressLinearScan is used
|
|
1040 |
return;
|
|
1041 |
}
|
|
1042 |
|
|
1043 |
// check that all successors of a block have a higher linear-scan-number
|
|
1044 |
// and that all predecessors of a block have a lower linear-scan-number
|
|
1045 |
// (only backward branches of loops are ignored)
|
|
1046 |
int i;
|
|
1047 |
for (i = 0; i < _linear_scan_order->length(); i++) {
|
|
1048 |
BlockBegin* cur = _linear_scan_order->at(i);
|
|
1049 |
|
|
1050 |
assert(cur->linear_scan_number() == i, "incorrect linear_scan_number");
|
|
1051 |
assert(cur->linear_scan_number() >= 0 && cur->linear_scan_number() == _linear_scan_order->index_of(cur), "incorrect linear_scan_number");
|
|
1052 |
|
|
1053 |
int j;
|
|
1054 |
for (j = cur->number_of_sux() - 1; j >= 0; j--) {
|
|
1055 |
BlockBegin* sux = cur->sux_at(j);
|
|
1056 |
|
|
1057 |
assert(sux->linear_scan_number() >= 0 && sux->linear_scan_number() == _linear_scan_order->index_of(sux), "incorrect linear_scan_number");
|
|
1058 |
if (!cur->is_set(BlockBegin::linear_scan_loop_end_flag)) {
|
|
1059 |
assert(cur->linear_scan_number() < sux->linear_scan_number(), "invalid order");
|
|
1060 |
}
|
|
1061 |
if (cur->loop_depth() == sux->loop_depth()) {
|
|
1062 |
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");
|
|
1063 |
}
|
|
1064 |
}
|
|
1065 |
|
|
1066 |
for (j = cur->number_of_preds() - 1; j >= 0; j--) {
|
|
1067 |
BlockBegin* pred = cur->pred_at(j);
|
|
1068 |
|
|
1069 |
assert(pred->linear_scan_number() >= 0 && pred->linear_scan_number() == _linear_scan_order->index_of(pred), "incorrect linear_scan_number");
|
|
1070 |
if (!cur->is_set(BlockBegin::linear_scan_loop_header_flag)) {
|
|
1071 |
assert(cur->linear_scan_number() > pred->linear_scan_number(), "invalid order");
|
|
1072 |
}
|
|
1073 |
if (cur->loop_depth() == pred->loop_depth()) {
|
|
1074 |
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");
|
|
1075 |
}
|
|
1076 |
|
|
1077 |
assert(cur->dominator()->linear_scan_number() <= cur->pred_at(j)->linear_scan_number(), "dominator must be before predecessors");
|
|
1078 |
}
|
|
1079 |
|
|
1080 |
// check dominator
|
|
1081 |
if (i == 0) {
|
|
1082 |
assert(cur->dominator() == NULL, "first block has no dominator");
|
|
1083 |
} else {
|
|
1084 |
assert(cur->dominator() != NULL, "all but first block must have dominator");
|
|
1085 |
}
|
|
1086 |
assert(cur->number_of_preds() != 1 || cur->dominator() == cur->pred_at(0), "Single predecessor must also be dominator");
|
|
1087 |
}
|
|
1088 |
|
|
1089 |
// check that all loops are continuous
|
|
1090 |
for (int loop_idx = 0; loop_idx < _num_loops; loop_idx++) {
|
|
1091 |
int block_idx = 0;
|
|
1092 |
assert(!is_block_in_loop(loop_idx, _linear_scan_order->at(block_idx)), "the first block must not be present in any loop");
|
|
1093 |
|
|
1094 |
// skip blocks before the loop
|
|
1095 |
while (block_idx < _num_blocks && !is_block_in_loop(loop_idx, _linear_scan_order->at(block_idx))) {
|
|
1096 |
block_idx++;
|
|
1097 |
}
|
|
1098 |
// skip blocks of loop
|
|
1099 |
while (block_idx < _num_blocks && is_block_in_loop(loop_idx, _linear_scan_order->at(block_idx))) {
|
|
1100 |
block_idx++;
|
|
1101 |
}
|
|
1102 |
// after the first non-loop block, there must not be another loop-block
|
|
1103 |
while (block_idx < _num_blocks) {
|
|
1104 |
assert(!is_block_in_loop(loop_idx, _linear_scan_order->at(block_idx)), "loop not continuous in linear-scan order");
|
|
1105 |
block_idx++;
|
|
1106 |
}
|
|
1107 |
}
|
|
1108 |
}
|
|
1109 |
#endif
|
|
1110 |
|
|
1111 |
|
|
1112 |
void IR::compute_code() {
|
|
1113 |
assert(is_valid(), "IR must be valid");
|
|
1114 |
|
|
1115 |
ComputeLinearScanOrder compute_order(start());
|
|
1116 |
_num_loops = compute_order.num_loops();
|
|
1117 |
_code = compute_order.linear_scan_order();
|
|
1118 |
}
|
|
1119 |
|
|
1120 |
|
|
1121 |
void IR::compute_use_counts() {
|
|
1122 |
// make sure all values coming out of this block get evaluated.
|
|
1123 |
int num_blocks = _code->length();
|
|
1124 |
for (int i = 0; i < num_blocks; i++) {
|
|
1125 |
_code->at(i)->end()->state()->pin_stack_for_linear_scan();
|
|
1126 |
}
|
|
1127 |
|
|
1128 |
// compute use counts
|
|
1129 |
UseCountComputer::compute(_code);
|
|
1130 |
}
|
|
1131 |
|
|
1132 |
|
|
1133 |
void IR::iterate_preorder(BlockClosure* closure) {
|
|
1134 |
assert(is_valid(), "IR must be valid");
|
|
1135 |
start()->iterate_preorder(closure);
|
|
1136 |
}
|
|
1137 |
|
|
1138 |
|
|
1139 |
void IR::iterate_postorder(BlockClosure* closure) {
|
|
1140 |
assert(is_valid(), "IR must be valid");
|
|
1141 |
start()->iterate_postorder(closure);
|
|
1142 |
}
|
|
1143 |
|
|
1144 |
void IR::iterate_linear_scan_order(BlockClosure* closure) {
|
|
1145 |
linear_scan_order()->iterate_forward(closure);
|
|
1146 |
}
|
|
1147 |
|
|
1148 |
|
|
1149 |
#ifndef PRODUCT
|
|
1150 |
class BlockPrinter: public BlockClosure {
|
|
1151 |
private:
|
|
1152 |
InstructionPrinter* _ip;
|
|
1153 |
bool _cfg_only;
|
|
1154 |
bool _live_only;
|
|
1155 |
|
|
1156 |
public:
|
|
1157 |
BlockPrinter(InstructionPrinter* ip, bool cfg_only, bool live_only = false) {
|
|
1158 |
_ip = ip;
|
|
1159 |
_cfg_only = cfg_only;
|
|
1160 |
_live_only = live_only;
|
|
1161 |
}
|
|
1162 |
|
|
1163 |
virtual void block_do(BlockBegin* block) {
|
|
1164 |
if (_cfg_only) {
|
|
1165 |
_ip->print_instr(block); tty->cr();
|
|
1166 |
} else {
|
|
1167 |
block->print_block(*_ip, _live_only);
|
|
1168 |
}
|
|
1169 |
}
|
|
1170 |
};
|
|
1171 |
|
|
1172 |
|
|
1173 |
void IR::print(BlockBegin* start, bool cfg_only, bool live_only) {
|
|
1174 |
ttyLocker ttyl;
|
|
1175 |
InstructionPrinter ip(!cfg_only);
|
|
1176 |
BlockPrinter bp(&ip, cfg_only, live_only);
|
|
1177 |
start->iterate_preorder(&bp);
|
|
1178 |
tty->cr();
|
|
1179 |
}
|
|
1180 |
|
|
1181 |
void IR::print(bool cfg_only, bool live_only) {
|
|
1182 |
if (is_valid()) {
|
|
1183 |
print(start(), cfg_only, live_only);
|
|
1184 |
} else {
|
|
1185 |
tty->print_cr("invalid IR");
|
|
1186 |
}
|
|
1187 |
}
|
|
1188 |
|
|
1189 |
|
|
1190 |
define_array(BlockListArray, BlockList*)
|
|
1191 |
define_stack(BlockListList, BlockListArray)
|
|
1192 |
|
|
1193 |
class PredecessorValidator : public BlockClosure {
|
|
1194 |
private:
|
|
1195 |
BlockListList* _predecessors;
|
|
1196 |
BlockList* _blocks;
|
|
1197 |
|
|
1198 |
static int cmp(BlockBegin** a, BlockBegin** b) {
|
|
1199 |
return (*a)->block_id() - (*b)->block_id();
|
|
1200 |
}
|
|
1201 |
|
|
1202 |
public:
|
|
1203 |
PredecessorValidator(IR* hir) {
|
|
1204 |
ResourceMark rm;
|
|
1205 |
_predecessors = new BlockListList(BlockBegin::number_of_blocks(), NULL);
|
|
1206 |
_blocks = new BlockList();
|
|
1207 |
|
|
1208 |
int i;
|
|
1209 |
hir->start()->iterate_preorder(this);
|
|
1210 |
if (hir->code() != NULL) {
|
|
1211 |
assert(hir->code()->length() == _blocks->length(), "must match");
|
|
1212 |
for (i = 0; i < _blocks->length(); i++) {
|
|
1213 |
assert(hir->code()->contains(_blocks->at(i)), "should be in both lists");
|
|
1214 |
}
|
|
1215 |
}
|
|
1216 |
|
|
1217 |
for (i = 0; i < _blocks->length(); i++) {
|
|
1218 |
BlockBegin* block = _blocks->at(i);
|
|
1219 |
BlockList* preds = _predecessors->at(block->block_id());
|
|
1220 |
if (preds == NULL) {
|
|
1221 |
assert(block->number_of_preds() == 0, "should be the same");
|
|
1222 |
continue;
|
|
1223 |
}
|
|
1224 |
|
|
1225 |
// clone the pred list so we can mutate it
|
|
1226 |
BlockList* pred_copy = new BlockList();
|
|
1227 |
int j;
|
|
1228 |
for (j = 0; j < block->number_of_preds(); j++) {
|
|
1229 |
pred_copy->append(block->pred_at(j));
|
|
1230 |
}
|
|
1231 |
// sort them in the same order
|
|
1232 |
preds->sort(cmp);
|
|
1233 |
pred_copy->sort(cmp);
|
|
1234 |
int length = MIN2(preds->length(), block->number_of_preds());
|
|
1235 |
for (j = 0; j < block->number_of_preds(); j++) {
|
|
1236 |
assert(preds->at(j) == pred_copy->at(j), "must match");
|
|
1237 |
}
|
|
1238 |
|
|
1239 |
assert(preds->length() == block->number_of_preds(), "should be the same");
|
|
1240 |
}
|
|
1241 |
}
|
|
1242 |
|
|
1243 |
virtual void block_do(BlockBegin* block) {
|
|
1244 |
_blocks->append(block);
|
|
1245 |
BlockEnd* be = block->end();
|
|
1246 |
int n = be->number_of_sux();
|
|
1247 |
int i;
|
|
1248 |
for (i = 0; i < n; i++) {
|
|
1249 |
BlockBegin* sux = be->sux_at(i);
|
|
1250 |
assert(!sux->is_set(BlockBegin::exception_entry_flag), "must not be xhandler");
|
|
1251 |
|
|
1252 |
BlockList* preds = _predecessors->at_grow(sux->block_id(), NULL);
|
|
1253 |
if (preds == NULL) {
|
|
1254 |
preds = new BlockList();
|
|
1255 |
_predecessors->at_put(sux->block_id(), preds);
|
|
1256 |
}
|
|
1257 |
preds->append(block);
|
|
1258 |
}
|
|
1259 |
|
|
1260 |
n = block->number_of_exception_handlers();
|
|
1261 |
for (i = 0; i < n; i++) {
|
|
1262 |
BlockBegin* sux = block->exception_handler_at(i);
|
|
1263 |
assert(sux->is_set(BlockBegin::exception_entry_flag), "must be xhandler");
|
|
1264 |
|
|
1265 |
BlockList* preds = _predecessors->at_grow(sux->block_id(), NULL);
|
|
1266 |
if (preds == NULL) {
|
|
1267 |
preds = new BlockList();
|
|
1268 |
_predecessors->at_put(sux->block_id(), preds);
|
|
1269 |
}
|
|
1270 |
preds->append(block);
|
|
1271 |
}
|
|
1272 |
}
|
|
1273 |
};
|
|
1274 |
|
|
1275 |
void IR::verify() {
|
|
1276 |
#ifdef ASSERT
|
|
1277 |
PredecessorValidator pv(this);
|
|
1278 |
#endif
|
|
1279 |
}
|
|
1280 |
|
|
1281 |
#endif // PRODUCT
|
|
1282 |
|
|
1283 |
void SubstitutionResolver::substitute(Value* v) {
|
|
1284 |
Value v0 = *v;
|
|
1285 |
if (v0) {
|
|
1286 |
Value vs = v0->subst();
|
|
1287 |
if (vs != v0) {
|
|
1288 |
*v = v0->subst();
|
|
1289 |
}
|
|
1290 |
}
|
|
1291 |
}
|
|
1292 |
|
|
1293 |
#ifdef ASSERT
|
|
1294 |
void check_substitute(Value* v) {
|
|
1295 |
Value v0 = *v;
|
|
1296 |
if (v0) {
|
|
1297 |
Value vs = v0->subst();
|
|
1298 |
assert(vs == v0, "missed substitution");
|
|
1299 |
}
|
|
1300 |
}
|
|
1301 |
#endif
|
|
1302 |
|
|
1303 |
|
|
1304 |
void SubstitutionResolver::block_do(BlockBegin* block) {
|
|
1305 |
Instruction* last = NULL;
|
|
1306 |
for (Instruction* n = block; n != NULL;) {
|
|
1307 |
n->values_do(substitute);
|
|
1308 |
// need to remove this instruction from the instruction stream
|
|
1309 |
if (n->subst() != n) {
|
|
1310 |
assert(last != NULL, "must have last");
|
|
1311 |
last->set_next(n->next(), n->next()->bci());
|
|
1312 |
} else {
|
|
1313 |
last = n;
|
|
1314 |
}
|
|
1315 |
n = last->next();
|
|
1316 |
}
|
|
1317 |
|
|
1318 |
#ifdef ASSERT
|
|
1319 |
if (block->state()) block->state()->values_do(check_substitute);
|
|
1320 |
block->block_values_do(check_substitute);
|
|
1321 |
if (block->end() && block->end()->state()) block->end()->state()->values_do(check_substitute);
|
|
1322 |
#endif
|
|
1323 |
}
|