llvm-project/compiler-rt/lib/ubsan/ubsan_win_dynamic_runtime_t...

//===-- ubsan_win_dynamic_runtime_thunk.cc --------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines things that need to be present in the application modules
// to interact with Ubsan, when it is included in a dll.
//
//===----------------------------------------------------------------------===//
#ifdef SANITIZER_DYNAMIC_RUNTIME_THUNK
#define SANITIZER_IMPORT_INTERFACE 1
#include "sanitizer_common/sanitizer_win_defs.h"
// Define weak alias for all weak functions imported from ubsan.
#define INTERFACE_FUNCTION(Name)
#define INTERFACE_WEAK_FUNCTION(Name) WIN_WEAK_IMPORT_DEF(Name)
#include "ubsan_interface.inc"
#endif // SANITIZER_DYNAMIC_RUNTIME_THUNK
[sanitizer] Add dynamic_runtime_thunk for different sanitizers. In Windows, when the sanitizer is implemented as a shared library (DLL), we need an auxiliary static library dynamic_runtime_thunk that will be linked to the main executable and dlls. In the sanitizer DLL, we are exposing weak functions with WIN_WEAK_EXPORT_DEF(), which exports the default implementation with __dll suffix. For example: for sanitizer coverage, the default implementation of __sanitizer_cov_trace_cmp is exported as: __sanitizer_cov_trace_cmp__dll. In the dynamic_runtime_thunk static library, we include weak aliases to the imported implementation from the dll, using the macro WIN_WEAK_IMPORT_DEF(). By default, all users's programs that include calls to weak functions like __sanitizer_cov_trace_cmp, will be redirected to the implementation in the dll, when linking to dynamic_runtime_thunk. After this diff, we are able to compile code with sanitizer coverage instrumentation on Windows. When the instrumented object files are linked with clang-rt_asan_dynamic_runtime_thunk-arch.lib all the weak symbols will be resolved to the implementation imported from asan dll. All the files sanitizer_dynamic_runtime_thunk.cc are independent, so we do not need to include a specific list of sanitizers. Now, we compile: [asan\|ubsan\|sanitizer_coverage]_win_dynamic_runtime_thunk.cc and sanitizer_win_dynamic_runtime_thunk.cc to generate asan_dynamic_runtime_thunk.lib, because we include asan, ubsan and sanitizer coverage in the address sanitizer library. Differential Revision: https://reviews.llvm.org/D29158 llvm-svn: 293953 2017-02-03 07:01:41 +08:00			`//===-- ubsan_win_dynamic_runtime_thunk.cc --------------------------------===//`
			`//`
			`// The LLVM Compiler Infrastructure`
			`//`
			`// This file is distributed under the University of Illinois Open Source`
			`// License. See LICENSE.TXT for details.`
			`//`
			`//===----------------------------------------------------------------------===//`
			`//`
			`// This file defines things that need to be present in the application modules`
			`// to interact with Ubsan, when it is included in a dll.`
			`//`
			`//===----------------------------------------------------------------------===//`
			`#ifdef SANITIZER_DYNAMIC_RUNTIME_THUNK`
			`#define SANITIZER_IMPORT_INTERFACE 1`
			`#include "sanitizer_common/sanitizer_win_defs.h"`
			`// Define weak alias for all weak functions imported from ubsan.`
			`#define INTERFACE_FUNCTION(Name)`
			`#define INTERFACE_WEAK_FUNCTION(Name) WIN_WEAK_IMPORT_DEF(Name)`
			`#include "ubsan_interface.inc"`
			`#endif // SANITIZER_DYNAMIC_RUNTIME_THUNK`