102 lines
3.6 KiB
C++
102 lines
3.6 KiB
C++
|
/* Copyright (C) 2008-2022 Free Software Foundation, Inc.
|
||
|
|
Contributed by Richard Henderson <rth@redhat.com>.
|
||
|
|
|
||
|
|
This file is part of the GNU Transactional Memory Library (libitm).
|
||
|
|
|
||
|
|
Libitm is free software; you can redistribute it and/or modify it
|
||
|
|
under the terms of the GNU General Public License as published by
|
||
|
|
the Free Software Foundation; either version 3 of the License, or
|
||
|
|
(at your option) any later version.
|
||
|
|
|
||
|
|
Libitm 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 for
|
||
|
|
more details.
|
||
|
|
|
||
|
|
Under Section 7 of GPL version 3, you are granted additional
|
||
|
|
permissions described in the GCC Runtime Library Exception, version
|
||
|
|
3.1, as published by the Free Software Foundation.
|
||
|
|
|
||
|
|
You should have received a copy of the GNU General Public License and
|
||
|
|
a copy of the GCC Runtime Library Exception along with this program;
|
||
|
|
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
|
||
|
|
<http://www.gnu.org/licenses/>. */
|
||
|
|
|
||
|
|
#include "libitm_i.h"
|
||
|
|
|
||
|
|
namespace GTM HIDDEN {
|
||
|
|
|
||
|
|
// This function needs to be noinline because we need to prevent that it gets
|
||
|
|
// inlined into another function that calls further functions. This could
|
||
|
|
// break our assumption that we only call memcpy and thus only need to
|
||
|
|
// additionally protect the memcpy stack (see the hack in mask_stack_bottom()).
|
||
|
|
// Even if that isn't an issue because those other calls don't happen during
|
||
|
|
// copying, we still need mask_stack_bottom() to be called "close" to the
|
||
|
|
// memcpy in terms of stack frames, so just ensure that for now using the
|
||
|
|
// noinline.
|
||
|
|
void __attribute__((noinline))
|
||
|
|
gtm_undolog::rollback (gtm_thread* tx, size_t until_size)
|
||
|
|
{
|
||
|
|
size_t i, n = undolog.size();
|
||
|
|
void *top = mask_stack_top(tx);
|
||
|
|
void *bot = mask_stack_bottom(tx);
|
||
|
|
|
||
|
|
if (n > 0)
|
||
|
|
{
|
||
|
|
for (i = n; i-- > until_size; )
|
||
|
|
{
|
||
|
|
void *ptr = (void *) undolog[i--];
|
||
|
|
size_t len = undolog[i];
|
||
|
|
size_t words = (len + sizeof(gtm_word) - 1) / sizeof(gtm_word);
|
||
|
|
i -= words;
|
||
|
|
// Filter out any updates that overlap the libitm stack. We don't
|
||
|
|
// bother filtering out just the overlapping bytes because we don't
|
||
|
|
// merge writes and thus any overlapping write is either bogus or
|
||
|
|
// would restore data on stack frames that are not in use anymore.
|
||
|
|
// FIXME The memcpy can/will end up as another call but we
|
||
|
|
// calculated BOT based on the current function. Can we inline or
|
||
|
|
// reimplement this without too much trouble due to unaligned calls
|
||
|
|
// and still have good performance, so that we can remove the hack
|
||
|
|
// in mask_stack_bottom()?
|
||
|
|
if (likely(ptr > top || (uint8_t*)ptr + len <= bot))
|
||
|
|
__builtin_memcpy (ptr, &undolog[i], len);
|
||
|
|
}
|
||
|
|
undolog.set_size(until_size);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void ITM_REGPARM
|
||
|
|
GTM_LB (const void *ptr, size_t len)
|
||
|
|
{
|
||
|
|
gtm_thread *tx = gtm_thr();
|
||
|
|
tx->undolog.log(ptr, len);
|
||
|
|
}
|
||
|
|
|
||
|
|
} // namespace GTM
|
||
|
|
|
||
|
|
using namespace GTM;
|
||
|
|
|
||
|
|
/* ??? Use configure to determine if aliases are supported. Or convince
|
||
|
|
the compiler to not just tail call this, but actually generate the
|
||
|
|
same_body_alias itself. */
|
||
|
|
void ITM_REGPARM
|
||
|
|
_ITM_LB (const void *ptr, size_t len)
|
||
|
|
{
|
||
|
|
GTM_LB (ptr, len);
|
||
|
|
}
|
||
|
|
|
||
|
|
#define ITM_LOG_DEF(T) \
|
||
|
|
void ITM_REGPARM _ITM_L##T (const _ITM_TYPE_##T *ptr) \
|
||
|
|
{ GTM_LB (ptr, sizeof (*ptr)); }
|
||
|
|
|
||
|
|
ITM_LOG_DEF(U1)
|
||
|
|
ITM_LOG_DEF(U2)
|
||
|
|
ITM_LOG_DEF(U4)
|
||
|
|
ITM_LOG_DEF(U8)
|
||
|
|
ITM_LOG_DEF(F)
|
||
|
|
ITM_LOG_DEF(D)
|
||
|
|
ITM_LOG_DEF(E)
|
||
|
|
ITM_LOG_DEF(CF)
|
||
|
|
ITM_LOG_DEF(CD)
|
||
|
|
ITM_LOG_DEF(CE)
|