blob: 8d9f3b9b4181a9057cfffffb164e33a097e21d1a [file] [log] [blame]
Paul Kirth4d437782024-01-30 23:03:14 +00001/*
2 * Copyright (C) 2024 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
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9 * notice, this list of conditions and the following disclaimer.
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14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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27 */
28
29#pragma once
30
31#if defined(__riscv)
32// TLS_DTV_OFFSET is a constant used in relocation fields, defined in RISC-V ELF Specification[1]
33// The front of the TCB contains a pointer to the DTV, and each pointer in DTV
34// points to 0x800 past the start of a TLS block to make full use of the range
35// of load/store instructions, refer to [2].
36//
37// [1]: RISC-V ELF Specification.
38// https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/master/riscv-elf.adoc#constants
39// [2]: Documentation of TLS data structures
40// https://github.com/riscv-non-isa/riscv-elf-psabi-doc/issues/53
41#define TLS_DTV_OFFSET 0x800
42#else
43#define TLS_DTV_OFFSET 0
44#endif