Mercurial > hg > graal-compiler
view src/share/vm/ci/ciMethodBlocks.cpp @ 2149:7e37af9d69ef
7011379: G1: overly long concurrent marking cycles
Summary: This changeset introduces filtering of SATB buffers at the point when they are about to be enqueued. If this filtering clears enough entries on each buffer, the buffer can then be re-used and not enqueued. This cuts down the number of SATB buffers that need to be processed by the concurrent marking threads.
Reviewed-by: johnc, ysr
author | tonyp |
---|---|
date | Wed, 19 Jan 2011 09:35:17 -0500 |
parents | f95d63e2154a |
children | 8012aa3ccede |
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/* * Copyright (c) 2006, 2010, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include "precompiled.hpp" #include "ci/ciMethodBlocks.hpp" #include "ci/ciStreams.hpp" #include "interpreter/bytecode.hpp" #include "utilities/copy.hpp" // ciMethodBlocks ciBlock *ciMethodBlocks::block_containing(int bci) { ciBlock *blk = _bci_to_block[bci]; return blk; } bool ciMethodBlocks::is_block_start(int bci) { assert(bci >=0 && bci < _code_size, "valid bytecode range"); ciBlock *b = _bci_to_block[bci]; assert(b != NULL, "must have block for bytecode"); return b->start_bci() == bci; } // ------------------------------------------------------------------ // ciMethodBlocks::split_block_at // // Split the block spanning bci into two separate ranges. The former // block becomes the second half and a new range is created for the // first half. Returns the range beginning at bci. ciBlock *ciMethodBlocks::split_block_at(int bci) { ciBlock *former_block = block_containing(bci); ciBlock *new_block = new(_arena) ciBlock(_method, _num_blocks++, former_block->start_bci()); _blocks->append(new_block); assert(former_block != NULL, "must not be NULL"); new_block->set_limit_bci(bci); former_block->set_start_bci(bci); for (int pos=bci-1; pos >= 0; pos--) { ciBlock *current_block = block_containing(pos); if (current_block == former_block) { // Replace it. _bci_to_block[pos] = new_block; } else if (current_block == NULL) { // Non-bytecode start. Skip. continue; } else { // We are done with our backwards walk break; } } // Move an exception handler information if needed. if (former_block->is_handler()) { int ex_start = former_block->ex_start_bci(); int ex_end = former_block->ex_limit_bci(); new_block->set_exception_range(ex_start, ex_end); // Clear information in former_block. former_block->clear_exception_handler(); } return former_block; } ciBlock *ciMethodBlocks::make_block_at(int bci) { ciBlock *cb = block_containing(bci); if (cb == NULL ) { // This is our first time visiting this bytecode. Create // a fresh block and assign it this starting point. ciBlock *nb = new(_arena) ciBlock(_method, _num_blocks++, bci); _blocks->append(nb); _bci_to_block[bci] = nb; return nb; } else if (cb->start_bci() == bci) { // The block begins at bci. Simply return it. return cb; } else { // We have already created a block containing bci but // not starting at bci. This existing block needs to // be split into two. return split_block_at(bci); } } ciBlock *ciMethodBlocks::make_dummy_block() { ciBlock *dum = new(_arena) ciBlock(_method, -1, 0); return dum; } void ciMethodBlocks::do_analysis() { ciBytecodeStream s(_method); ciBlock *cur_block = block_containing(0); int limit_bci = _method->code_size(); while (s.next() != ciBytecodeStream::EOBC()) { int bci = s.cur_bci(); // Determine if a new block has been made at the current bci. If // this block differs from our current range, switch to the new // one and end the old one. assert(cur_block != NULL, "must always have a current block"); ciBlock *new_block = block_containing(bci); if (new_block == NULL || new_block == cur_block) { // We have not marked this bci as the start of a new block. // Keep interpreting the current_range. _bci_to_block[bci] = cur_block; } else { cur_block->set_limit_bci(bci); cur_block = new_block; } switch (s.cur_bc()) { case Bytecodes::_ifeq : case Bytecodes::_ifne : case Bytecodes::_iflt : case Bytecodes::_ifge : case Bytecodes::_ifgt : case Bytecodes::_ifle : case Bytecodes::_if_icmpeq : case Bytecodes::_if_icmpne : case Bytecodes::_if_icmplt : case Bytecodes::_if_icmpge : case Bytecodes::_if_icmpgt : case Bytecodes::_if_icmple : case Bytecodes::_if_acmpeq : case Bytecodes::_if_acmpne : case Bytecodes::_ifnull : case Bytecodes::_ifnonnull : { cur_block->set_control_bci(bci); ciBlock *fall_through = make_block_at(s.next_bci()); int dest_bci = s.get_dest(); ciBlock *dest = make_block_at(dest_bci); break; } case Bytecodes::_goto : { cur_block->set_control_bci(bci); if (s.next_bci() < limit_bci) { (void) make_block_at(s.next_bci()); } int dest_bci = s.get_dest(); ciBlock *dest = make_block_at(dest_bci); break; } case Bytecodes::_jsr : { cur_block->set_control_bci(bci); ciBlock *ret = make_block_at(s.next_bci()); int dest_bci = s.get_dest(); ciBlock *dest = make_block_at(dest_bci); break; } case Bytecodes::_tableswitch : { cur_block->set_control_bci(bci); Bytecode_tableswitch* switch_ = Bytecode_tableswitch_at(s.cur_bcp()); int len = switch_->length(); ciBlock *dest; int dest_bci; for (int i = 0; i < len; i++) { dest_bci = s.cur_bci() + switch_->dest_offset_at(i); dest = make_block_at(dest_bci); } dest_bci = s.cur_bci() + switch_->default_offset(); make_block_at(dest_bci); if (s.next_bci() < limit_bci) { dest = make_block_at(s.next_bci()); } } break; case Bytecodes::_lookupswitch: { cur_block->set_control_bci(bci); Bytecode_lookupswitch* switch_ = Bytecode_lookupswitch_at(s.cur_bcp()); int len = switch_->number_of_pairs(); ciBlock *dest; int dest_bci; for (int i = 0; i < len; i++) { dest_bci = s.cur_bci() + switch_->pair_at(i)->offset(); dest = make_block_at(dest_bci); } dest_bci = s.cur_bci() + switch_->default_offset(); dest = make_block_at(dest_bci); if (s.next_bci() < limit_bci) { dest = make_block_at(s.next_bci()); } } break; case Bytecodes::_goto_w : { cur_block->set_control_bci(bci); if (s.next_bci() < limit_bci) { (void) make_block_at(s.next_bci()); } int dest_bci = s.get_far_dest(); ciBlock *dest = make_block_at(dest_bci); break; } case Bytecodes::_jsr_w : { cur_block->set_control_bci(bci); ciBlock *ret = make_block_at(s.next_bci()); int dest_bci = s.get_far_dest(); ciBlock *dest = make_block_at(dest_bci); break; } case Bytecodes::_athrow : cur_block->set_may_throw(); // fall-through case Bytecodes::_ret : case Bytecodes::_ireturn : case Bytecodes::_lreturn : case Bytecodes::_freturn : case Bytecodes::_dreturn : case Bytecodes::_areturn : case Bytecodes::_return : cur_block->set_control_bci(bci); if (s.next_bci() < limit_bci) { (void) make_block_at(s.next_bci()); } break; } } // End the last block cur_block->set_limit_bci(limit_bci); } ciMethodBlocks::ciMethodBlocks(Arena *arena, ciMethod *meth): _method(meth), _arena(arena), _num_blocks(0), _code_size(meth->code_size()) { int block_estimate = _code_size / 8; _blocks = new(_arena) GrowableArray<ciBlock *>(_arena, block_estimate, 0, NULL); int b2bsize = _code_size * sizeof(ciBlock **); _bci_to_block = (ciBlock **) arena->Amalloc(b2bsize); Copy::zero_to_words((HeapWord*) _bci_to_block, b2bsize / sizeof(HeapWord)); // create initial block covering the entire method ciBlock *b = new(arena) ciBlock(_method, _num_blocks++, 0); _blocks->append(b); _bci_to_block[0] = b; // create blocks for exception handlers if (meth->has_exception_handlers()) { for(ciExceptionHandlerStream str(meth); !str.is_done(); str.next()) { ciExceptionHandler* handler = str.handler(); ciBlock *eb = make_block_at(handler->handler_bci()); // // Several exception handlers can have the same handler_bci: // // try { // if (a.foo(b) < 0) { // return a.error(); // } // return CoderResult.UNDERFLOW; // } finally { // a.position(b); // } // // The try block above is divided into 2 exception blocks // separated by 'areturn' bci. // int ex_start = handler->start(); int ex_end = handler->limit(); // ensure a block at the start of exception range and start of following code (void) make_block_at(ex_start); if (ex_end < _code_size) (void) make_block_at(ex_end); if (eb->is_handler()) { // Extend old handler exception range to cover additional range. int old_ex_start = eb->ex_start_bci(); int old_ex_end = eb->ex_limit_bci(); if (ex_start > old_ex_start) ex_start = old_ex_start; if (ex_end < old_ex_end) ex_end = old_ex_end; eb->clear_exception_handler(); // Reset exception information } eb->set_exception_range(ex_start, ex_end); } } // scan the bytecodes and identify blocks do_analysis(); // mark blocks that have exception handlers if (meth->has_exception_handlers()) { for(ciExceptionHandlerStream str(meth); !str.is_done(); str.next()) { ciExceptionHandler* handler = str.handler(); int ex_start = handler->start(); int ex_end = handler->limit(); int bci = ex_start; while (bci < ex_end) { ciBlock *b = block_containing(bci); b->set_has_handler(); bci = b->limit_bci(); } } } } void ciMethodBlocks::clear_processed() { for (int i = 0; i < _blocks->length(); i++) _blocks->at(i)->clear_processed(); } #ifndef PRODUCT void ciMethodBlocks::dump() { tty->print("---- blocks for method: "); _method->print(); tty->cr(); for (int i = 0; i < _blocks->length(); i++) { tty->print(" B%d: ", i); _blocks->at(i)->dump(); } } #endif ciBlock::ciBlock(ciMethod *method, int index, int start_bci) : #ifndef PRODUCT _method(method), #endif _idx(index), _flags(0), _start_bci(start_bci), _limit_bci(-1), _control_bci(fall_through_bci), _ex_start_bci(-1), _ex_limit_bci(-1) { } void ciBlock::set_exception_range(int start_bci, int limit_bci) { assert(limit_bci >= start_bci, "valid range"); assert(!is_handler() && _ex_start_bci == -1 && _ex_limit_bci == -1, "must not be handler"); _ex_start_bci = start_bci; _ex_limit_bci = limit_bci; set_handler(); } #ifndef PRODUCT static const char *flagnames[] = { "Processed", "Handler", "MayThrow", "Jsr", "Ret", "RetTarget", "HasHandler", }; void ciBlock::dump() { tty->print(" [%d .. %d), {", _start_bci, _limit_bci); for (int i = 0; i < 8; i++) { if ((_flags & (1 << i)) != 0) { tty->print(" %s", flagnames[i]); } } tty->print(" ]"); if (is_handler()) tty->print(" handles(%d..%d)", _ex_start_bci, _ex_limit_bci); tty->cr(); } // ------------------------------------------------------------------ // ciBlock::print_on void ciBlock::print_on(outputStream* st) const { st->print_cr("--------------------------------------------------------"); st->print ("ciBlock [%d - %d) control : ", start_bci(), limit_bci()); if (control_bci() == fall_through_bci) { st->print_cr("%d:fall through", limit_bci()); } else { st->print_cr("%d:%s", control_bci(), Bytecodes::name(method()->java_code_at_bci(control_bci()))); } if (Verbose || WizardMode) { method()->print_codes_on(start_bci(), limit_bci(), st); } } #endif