1/*
2 * Copyright 2016 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#ifndef SkMSAN_DEFINED
9#define SkMSAN_DEFINED
10
11#include "SkTypes.h"
12
13// Typically declared in LLVM's msan_interface.h.  Easier for us to just re-declare.
14extern "C" {
15    void __msan_check_mem_is_initialized(const volatile void*, size_t);
16    void __msan_unpoison                (const volatile void*, size_t);
17}
18
19// Code that requires initialized inputs can call this to make it clear that
20// the blame for use of uninitialized data belongs further up the call stack.
21static inline void sk_msan_assert_initialized(const void* begin, const void* end) {
22#if defined(__has_feature)
23    #if __has_feature(memory_sanitizer)
24        __msan_check_mem_is_initialized(begin, (const char*)end - (const char*)begin);
25    #endif
26#endif
27}
28
29// Lie to MSAN that this range of memory is initialized.
30// This can hide serious problems if overused.  Every use of this should refer to a bug.
31static inline void sk_msan_mark_initialized(const void* begin, const void* end, const char* skbug) {
32    SkASSERT(skbug && 0 != strcmp(skbug, ""));
33#if defined(__has_feature)
34    #if __has_feature(memory_sanitizer)
35        __msan_unpoison(begin, (const char*)end - (const char*)begin);
36    #endif
37#endif
38}
39
40#endif//SkMSAN_DEFINED
41