// Copyright 2021 the V8 project authors. All rights reserved.

// Use of this source code is governed by a BSD-style license that can be

// found in the LICENSE file.

#include "src/heap/cppgc/memory.h"

#include <cstddef>

#include "src/heap/cppgc/globals.h"

namespace cppgc {

namespace internal {

void NoSanitizeMemset(void* address, char c, size_t bytes) {

volatile uint8_t* const base = static_cast<uint8_t*>(address);

for (size_t i = 0; i < bytes; ++i) {

base[i] = c;

}

}

#if defined(V8_USE_MEMORY_SANITIZER) || defined(V8_USE_ADDRESS_SANITIZER) || \

DEBUG

void SetMemoryAccessible(void* address, size_t size) {

#if defined(V8_USE_MEMORY_SANITIZER)

MSAN_MEMORY_IS_INITIALIZED(address, size);

#elif defined(V8_USE_ADDRESS_SANITIZER)

ASAN_UNPOISON_MEMORY_REGION(address, size);

#else // Debug builds.

memset(address, 0, size);

#endif // Debug builds.

}

void SetMemoryInaccessible(void* address, size_t size) {

#if defined(V8_USE_MEMORY_SANITIZER)

memset(address, 0, size);

MSAN_ALLOCATED_UNINITIALIZED_MEMORY(address, size);

#elif defined(V8_USE_ADDRESS_SANITIZER)

NoSanitizeMemset(address, 0, size);

ASAN_POISON_MEMORY_REGION(address, size);

#else

::cppgc::internal::ZapMemory(address, size);

#endif // Debug builds.

}

void CheckMemoryIsInaccessible(const void* address, size_t size) {

#if defined(V8_USE_MEMORY_SANITIZER)

static_assert(CheckMemoryIsInaccessibleIsNoop(),

"CheckMemoryIsInaccessibleIsNoop() needs to reflect "

"CheckMemoryIsInaccessible().");

// Unable to check that memory is marked as uninitialized by MSAN.

#elif defined(V8_USE_ADDRESS_SANITIZER)

static_assert(!CheckMemoryIsInaccessibleIsNoop(),

"CheckMemoryIsInaccessibleIsNoop() needs to reflect "

"CheckMemoryIsInaccessible().");

// Only check if memory is poisoned on 64 bit, since there we make sure that

// object sizes and alignments are multiple of shadow memory granularity.

#if defined(V8_HOST_ARCH_64_BIT)

ASAN_CHECK_WHOLE_MEMORY_REGION_IS_POISONED(address, size);

#endif

ASAN_UNPOISON_MEMORY_REGION(address, size);

CheckMemoryIsZero(address, size);

ASAN_POISON_MEMORY_REGION(address, size);

#else // Debug builds.

static_assert(!CheckMemoryIsInaccessibleIsNoop(),

"CheckMemoryIsInaccessibleIsNoop() needs to reflect "

"CheckMemoryIsInaccessible().");

CheckMemoryIsZapped(address, size);

#endif // Debug builds.

}

#endif

} // namespace internal

} // namespace cppgc