llvm-project

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//===-- asan_globals_win.cpp ----------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// Global registration code that is linked into every Windows DLL and EXE.
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//
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//===----------------------------------------------------------------------===//
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#include "asan_interface_internal.h"
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#if SANITIZER_WINDOWS
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namespace __asan {
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#pragma section(".ASAN$GA", read, write)
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#pragma section(".ASAN$GZ", read, write)
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extern "C" __declspec(allocate(".ASAN$GA"))
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    ALIGNED(sizeof(__asan_global)) __asan_global __asan_globals_start = {};
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extern "C" __declspec(allocate(".ASAN$GZ"))
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    ALIGNED(sizeof(__asan_global)) __asan_global __asan_globals_end = {};
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#pragma comment(linker, "/merge:.ASAN=.data")
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static void call_on_globals(void (*hook)(__asan_global *, uptr)) {
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  __asan_global *start = &__asan_globals_start + 1;
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  __asan_global *end = &__asan_globals_end;
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  uptr bytediff = (uptr)end - (uptr)start;
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  if (bytediff % sizeof(__asan_global) != 0) {
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#if defined(SANITIZER_DLL_THUNK) || defined(SANITIZER_DYNAMIC_RUNTIME_THUNK)
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    __debugbreak();
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#else
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    CHECK("corrupt asan global array");
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#endif
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  }
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  // We know end >= start because the linker sorts the portion after the dollar
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  // sign alphabetically.
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  uptr n = end - start;
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  hook(start, n);
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}
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static void register_dso_globals() {
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  call_on_globals(&__asan_register_globals);
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}
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static void unregister_dso_globals() {
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  call_on_globals(&__asan_unregister_globals);
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}
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// Register globals
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#pragma section(".CRT$XCU", long, read)
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#pragma section(".CRT$XTX", long, read)
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extern "C" __declspec(allocate(".CRT$XCU"))
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void (*const __asan_dso_reg_hook)() = &register_dso_globals;
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extern "C" __declspec(allocate(".CRT$XTX"))
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void (*const __asan_dso_unreg_hook)() = &unregister_dso_globals;
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} // namespace __asan
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#endif  // SANITIZER_WINDOWS
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