Ryan Prichard | 45d1349 | 2019-01-03 02:51:30 -0800 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2019 The Android Open Source Project |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * * Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * * Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in |
| 12 | * the documentation and/or other materials provided with the |
| 13 | * distribution. |
| 14 | * |
| 15 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 16 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 17 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| 18 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| 19 | * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 20 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| 21 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS |
| 22 | * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| 23 | * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| 24 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| 25 | * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 26 | * SUCH DAMAGE. |
| 27 | */ |
| 28 | |
| 29 | #pragma once |
| 30 | |
| 31 | #include <stdint.h> |
| 32 | |
| 33 | struct StaticTlsLayout { |
| 34 | constexpr StaticTlsLayout() {} |
| 35 | |
| 36 | private: |
| 37 | size_t offset_ = 0; |
| 38 | size_t alignment_ = 1; |
| 39 | bool overflowed_ = false; |
| 40 | |
| 41 | // Offsets to various Bionic TLS structs from the beginning of static TLS. |
| 42 | size_t offset_bionic_tcb_ = SIZE_MAX; |
| 43 | size_t offset_bionic_tls_ = SIZE_MAX; |
| 44 | |
| 45 | public: |
| 46 | size_t offset_bionic_tcb() const { return offset_bionic_tcb_; } |
| 47 | size_t offset_bionic_tls() const { return offset_bionic_tls_; } |
| 48 | |
| 49 | size_t size() const { return offset_; } |
| 50 | size_t alignment() const { return alignment_; } |
| 51 | bool overflowed() const { return overflowed_; } |
| 52 | |
| 53 | void reserve_tcb(); |
| 54 | void reserve_bionic_tls(); |
| 55 | void finish_layout(); |
| 56 | |
| 57 | private: |
| 58 | size_t reserve(size_t size, size_t alignment); |
| 59 | |
| 60 | template <typename T> size_t reserve_type() { |
| 61 | return reserve(sizeof(T), alignof(T)); |
| 62 | } |
| 63 | |
| 64 | size_t round_up_with_overflow_check(size_t value, size_t alignment); |
| 65 | }; |