1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/os/windows/vm/chaitin_windows.cpp Sat Dec 01 00:00:00 2007 +0000
1.3 @@ -0,0 +1,77 @@
1.4 +/*
1.5 + * Copyright 1999-2006 Sun Microsystems, Inc. All Rights Reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
1.23 + * CA 95054 USA or visit www.sun.com if you need additional information or
1.24 + * have any questions.
1.25 + *
1.26 + */
1.27 +
1.28 +#include "incls/_precompiled.incl"
1.29 +#include "incls/_chaitin_windows.cpp.incl"
1.30 +
1.31 +// Disallow the use of the frame pointer (EBP) for implicit null exceptions
1.32 +// on win95/98. If we do not do this, the OS gets confused and gives a stack
1.33 +// error.
1.34 +void PhaseRegAlloc::pd_preallocate_hook() {
1.35 +#ifndef _WIN64
1.36 + if (ImplicitNullChecks && !os::win32::is_nt()) {
1.37 + for (uint block_num=1; block_num<_cfg._num_blocks; block_num++) {
1.38 + Block *block = _cfg._blocks[block_num];
1.39 +
1.40 + Node *block_end = block->end();
1.41 + if (block_end->is_MachNullCheck() &&
1.42 + block_end->as_Mach()->ideal_Opcode() != Op_Con) {
1.43 + // The last instruction in the block is an implicit null check.
1.44 + // Fix its input so that it does not load into the frame pointer.
1.45 + _matcher.pd_implicit_null_fixup(block_end->in(1)->as_Mach(),
1.46 + block_end->as_MachNullCheck()->_vidx);
1.47 + }
1.48 + }
1.49 + }
1.50 +#else
1.51 + // WIN64==itanium on XP
1.52 +#endif
1.53 +}
1.54 +
1.55 +#ifdef ASSERT
1.56 +// Verify that no implicit null check uses the frame pointer (EBP) as
1.57 +// its register on win95/98. Use of the frame pointer in an implicit
1.58 +// null check confuses the OS, yielding a stack error.
1.59 +void PhaseRegAlloc::pd_postallocate_verify_hook() {
1.60 +#ifndef _WIN64
1.61 + if (ImplicitNullChecks && !os::win32::is_nt()) {
1.62 + for (uint block_num=1; block_num<_cfg._num_blocks; block_num++) {
1.63 + Block *block = _cfg._blocks[block_num];
1.64 +
1.65 + Node *block_end = block->_nodes[block->_nodes.size()-1];
1.66 + if (block_end->is_MachNullCheck() && block_end->as_Mach()->ideal_Opcode() != Op_Con) {
1.67 + // The last instruction in the block is an implicit
1.68 + // null check. Verify that this instruction does not
1.69 + // use the frame pointer.
1.70 + int reg = get_reg_first(block_end->in(1)->in(block_end->as_MachNullCheck()->_vidx));
1.71 + assert(reg != EBP_num,
1.72 + "implicit null check using frame pointer on win95/98");
1.73 + }
1.74 + }
1.75 + }
1.76 +#else
1.77 + // WIN64==itanium on XP
1.78 +#endif
1.79 +}
1.80 +#endif
