1 files changed, 85 insertions, 0 deletions
diff --git a/deps/v8/src/base/memory.h b/deps/v8/src/base/memory.h
new file mode 100644
index 0000000000..087f67291d
--- /dev/null
+++ b/deps/v8/src/base/memory.h
@@ -0,0 +1,85 @@
+// Copyright 2011 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.
+
+#ifndef V8_BASE_MEMORY_H_
+#define V8_BASE_MEMORY_H_
+
+#include "src/base/macros.h"
+
+namespace v8 {
+namespace base {
+
+using Address = uintptr_t;
+using byte = uint8_t;
+
+// Memory provides an interface to 'raw' memory. It encapsulates the casts
+// that typically are needed when incompatible pointer types are used.
+// Note that this class currently relies on undefined behaviour. There is a
+// proposal (http://wg21.link/p0593r2) to make it defined behaviour though.
+template <class T>
+inline T& Memory(Address addr) {
+  DCHECK(IsAligned(addr, alignof(T)));
+  return *reinterpret_cast<T*>(addr);
+}
+template <class T>
+inline T& Memory(byte* addr) {
+  return Memory<T>(reinterpret_cast<Address>(addr));
+}
+
+template <typename V>
+static inline V ReadUnalignedValue(Address p) {
+  ASSERT_TRIVIALLY_COPYABLE(V);
+  V r;
+  memcpy(&r, reinterpret_cast<void*>(p), sizeof(V));
+  return r;
+}
+
+template <typename V>
+static inline void WriteUnalignedValue(Address p, V value) {
+  ASSERT_TRIVIALLY_COPYABLE(V);
+  memcpy(reinterpret_cast<void*>(p), &value, sizeof(V));
+}
+
+template <typename V>
+static inline V ReadLittleEndianValue(Address p) {
+#if defined(V8_TARGET_LITTLE_ENDIAN)
+  return ReadUnalignedValue<V>(p);
+#elif defined(V8_TARGET_BIG_ENDIAN)
+  V ret{};
+  const byte* src = reinterpret_cast<const byte*>(p);
+  byte* dst = reinterpret_cast<byte*>(&ret);
+  for (size_t i = 0; i < sizeof(V); i++) {
+    dst[i] = src[sizeof(V) - i - 1];
+  }
+  return ret;
+#endif  // V8_TARGET_LITTLE_ENDIAN
+}
+
+template <typename V>
+static inline void WriteLittleEndianValue(Address p, V value) {
+#if defined(V8_TARGET_LITTLE_ENDIAN)
+  WriteUnalignedValue<V>(p, value);
+#elif defined(V8_TARGET_BIG_ENDIAN)
+  byte* src = reinterpret_cast<byte*>(&value);
+  byte* dst = reinterpret_cast<byte*>(p);
+  for (size_t i = 0; i < sizeof(V); i++) {
+    dst[i] = src[sizeof(V) - i - 1];
+  }
+#endif  // V8_TARGET_LITTLE_ENDIAN
+}
+
+template <typename V>
+static inline V ReadLittleEndianValue(V* p) {
+  return ReadLittleEndianValue<V>(reinterpret_cast<Address>(p));
+}
+
+template <typename V>
+static inline void WriteLittleEndianValue(V* p, V value) {
+  WriteLittleEndianValue<V>(reinterpret_cast<Address>(p), value);
+}
+
+}  // namespace base
+}  // namespace v8
+
+#endif  // V8_BASE_MEMORY_H_