/* * Copyright (c) 1998, 2019, 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 "code/exceptionHandlerTable.hpp" #include "code/nmethod.hpp" #include "memory/allocation.inline.hpp" void ExceptionHandlerTable::add_entry(HandlerTableEntry entry) { _nesting.check(); if (_length >= _size) { // not enough space => grow the table (amortized growth, double its size) guarantee(_size > 0, "no space allocated => cannot grow the table since it is part of nmethod"); int new_size = _size * 2; _table = REALLOC_RESOURCE_ARRAY(HandlerTableEntry, _table, _size, new_size); _size = new_size; } assert(_length < _size, "sanity check"); _table[_length++] = entry; } HandlerTableEntry* ExceptionHandlerTable::subtable_for(int catch_pco) const { int i = 0; while (i < _length) { HandlerTableEntry* t = _table + i; if (t->pco() == catch_pco) { // found subtable matching the catch_pco return t; } else { // advance to next subtable i += t->len() + 1; // +1 for header } } return NULL; } ExceptionHandlerTable::ExceptionHandlerTable(int initial_size) { guarantee(initial_size > 0, "initial size must be > 0"); _table = NEW_RESOURCE_ARRAY(HandlerTableEntry, initial_size); _length = 0; _size = initial_size; } ExceptionHandlerTable::ExceptionHandlerTable(const CompiledMethod* cm) { _table = (HandlerTableEntry*)cm->handler_table_begin(); _length = cm->handler_table_size() / sizeof(HandlerTableEntry); _size = 0; // no space allocated by ExeptionHandlerTable! } void ExceptionHandlerTable::add_subtable( int catch_pco, GrowableArray* handler_bcis, GrowableArray* scope_depths_from_top_scope, GrowableArray* handler_pcos ) { assert(subtable_for(catch_pco) == NULL, "catch handlers for this catch_pco added twice"); assert(handler_bcis->length() == handler_pcos->length(), "bci & pc table have different length"); assert(scope_depths_from_top_scope == NULL || handler_bcis->length() == scope_depths_from_top_scope->length(), "bci & scope_depths table have different length"); if (handler_bcis->length() > 0) { // add subtable header add_entry(HandlerTableEntry(handler_bcis->length(), catch_pco, 0)); // add individual entries for (int i = 0; i < handler_bcis->length(); i++) { intptr_t scope_depth = 0; if (scope_depths_from_top_scope != NULL) { scope_depth = scope_depths_from_top_scope->at(i); } add_entry(HandlerTableEntry(handler_bcis->at(i), handler_pcos->at(i), scope_depth)); assert(entry_for(catch_pco, handler_bcis->at(i), scope_depth)->pco() == handler_pcos->at(i), "entry not added correctly (1)"); assert(entry_for(catch_pco, handler_bcis->at(i), scope_depth)->scope_depth() == scope_depth, "entry not added correctly (2)"); } } } void ExceptionHandlerTable::copy_to(CompiledMethod* cm) { assert(size_in_bytes() == cm->handler_table_size(), "size of space allocated in compiled method incorrect"); copy_bytes_to(cm->handler_table_begin()); } void ExceptionHandlerTable::copy_bytes_to(address addr) { memmove(addr, _table, size_in_bytes()); } HandlerTableEntry* ExceptionHandlerTable::entry_for(int catch_pco, int handler_bci, int scope_depth) const { HandlerTableEntry* t = subtable_for(catch_pco); if (t != NULL) { int l = t->len(); while (l-- > 0) { t++; if (t->bci() == handler_bci && t->scope_depth() == scope_depth) return t; } } return NULL; } void ExceptionHandlerTable::print_subtable(HandlerTableEntry* t) const { int l = t->len(); tty->print_cr("catch_pco = %d (%d entries)", t->pco(), l); while (l-- > 0) { t++; tty->print_cr(" bci %d at scope depth %d -> pco %d", t->bci(), t->scope_depth(), t->pco()); } } void ExceptionHandlerTable::print() const { tty->print_cr("ExceptionHandlerTable (size = %d bytes)", size_in_bytes()); int i = 0; while (i < _length) { HandlerTableEntry* t = _table + i; print_subtable(t); // advance to next subtable i += t->len() + 1; // +1 for header } } void ExceptionHandlerTable::print_subtable_for(int catch_pco) const { HandlerTableEntry* subtable = subtable_for(catch_pco); if( subtable != NULL ) { print_subtable( subtable ); } } // ---------------------------------------------------------------------------- // Implicit null exception tables. Maps an exception PC offset to a // continuation PC offset. During construction it's a variable sized // array with a max size and current length. When stored inside an // nmethod a zero length table takes no space. This is detected by // nul_chk_table_size() == 0. Otherwise the table has a length word // followed by pairs of . void ImplicitExceptionTable::set_size( uint size ) { _size = size; _data = NEW_RESOURCE_ARRAY(implicit_null_entry, (size*2)); _len = 0; } void ImplicitExceptionTable::append( uint exec_off, uint cont_off ) { assert( (sizeof(implicit_null_entry) >= 4) || (exec_off < 65535), "" ); assert( (sizeof(implicit_null_entry) >= 4) || (cont_off < 65535), "" ); uint l = len(); if (l == _size) { uint old_size_in_elements = _size*2; if (_size == 0) _size = 4; _size *= 2; uint new_size_in_elements = _size*2; _data = REALLOC_RESOURCE_ARRAY(uint, _data, old_size_in_elements, new_size_in_elements); } *(adr(l) ) = exec_off; *(adr(l)+1) = cont_off; _len = l+1; }; uint ImplicitExceptionTable::at( uint exec_off ) const { uint l = len(); for( uint i=0; i 0) { const uint items_per_line = 3; uint i; tty->print_cr("ImplicitExceptionTable (size = %d entries, %d bytes):", n, size_in_bytes()); tty->print("{"); for (i = 0; i < n; i++) { if (i%items_per_line == 0) { tty->cr(); tty->fill_to(3); } tty->print("< " INTPTR_FORMAT ", " INTPTR_FORMAT " > ", p2i(base + *adr(i)), p2i(base + *(adr(i)+1))); } tty->bol(); tty->print_cr("}"); } else { tty->print_cr("ImplicitExceptionTable is empty"); } } ImplicitExceptionTable::ImplicitExceptionTable(const nmethod* nm) { if (nm->nul_chk_table_size() == 0) { _len = 0; _data = NULL; } else { // the first word is the length if non-zero, so read it out and // skip to the next word to get the table. _data = (implicit_null_entry*)nm->nul_chk_table_begin(); _len = _data[0]; _data++; } _size = len(); assert(size_in_bytes() <= nm->nul_chk_table_size(), "size of space allocated in nmethod incorrect"); } void ImplicitExceptionTable::copy_to( nmethod* nm ) { assert(size_in_bytes() <= nm->nul_chk_table_size(), "size of space allocated in nmethod incorrect"); if (len() != 0) { implicit_null_entry* nmdata = (implicit_null_entry*)nm->nul_chk_table_begin(); // store the length in the first uint nmdata[0] = _len; nmdata++; // copy the table after the length memmove( nmdata, _data, 2 * len() * sizeof(implicit_null_entry)); } else { // zero length table takes zero bytes assert(size_in_bytes() == 0, "bad size"); assert(nm->nul_chk_table_size() == 0, "bad size"); } } void ImplicitExceptionTable::verify(nmethod *nm) const { for (uint i = 0; i < len(); i++) { if ((*adr(i) > (unsigned int)nm->insts_size()) || (*(adr(i)+1) > (unsigned int)nm->insts_size())) fatal("Invalid offset in ImplicitExceptionTable at " PTR_FORMAT, p2i(_data)); } }