include/swift/Basic/Malloc.h

//===--- Malloc.h - Aligned malloc interface --------------------*- C++ -*-===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
//
//  This file provides an implementation of C11 aligned_alloc(3) for platforms
//  that don't have it yet, using posix_memalign(3).
//
//===----------------------------------------------------------------------===//

#ifndef SWIFT_BASIC_MALLOC_H
#define SWIFT_BASIC_MALLOC_H

#include <cassert>
#if defined(_WIN32)
#include <malloc.h>
#else
#include <cstdlib>
#endif

namespace swift {

// FIXME: Use C11 aligned_alloc if available.
inline void *AlignedAlloc(size_t size, size_t align) {
  // posix_memalign only accepts alignments greater than sizeof(void*).
  // 
  if (align < sizeof(void*))
    align = sizeof(void*);
  
  void *r;
#if defined(_WIN32)
  r = _aligned_malloc(size, align);
  assert(r && "_aligned_malloc failed");
#else
  int res = posix_memalign(&r, align, size);
  assert(res == 0 && "posix_memalign failed");
  (void)res; // Silence the unused variable warning.
#endif
  return r;
}

inline void AlignedFree(void *p) {
#if defined(_WIN32)
  _aligned_free(p);
#else
  free(p);
#endif
}

} // end namespace swift

#endif // SWIFT_BASIC_MALLOC_H