| /* 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) |