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/*
 RCC-Project

 Copyright (C) 2026 Richard Qin

 This file is part of RCC-Project.

 RCC-Project is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free
 Software Foundation; either version 3 of the License, or (at your option) any
 later version.

 RCC-Project is distributed in the hope that it will be useful, but WITHOUT ANY
 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

 You should have received a copy of the GNU General Public License along with
 RCC-Project; see the file COPYING.  If not see
 <http://www.gnu.org/licenses/>.
 */

//===- MemAlloc.h - Memory allocation functions -----------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
/// \file
///
/// This file defines counterparts of C library allocation functions defined in
/// the namespace 'std'. The new allocation functions crash on allocation
/// failure instead of returning null pointer.
///
//===----------------------------------------------------------------------===//

#ifndef RCC_SUPPORT_MEMALLOC_H
#define RCC_SUPPORT_MEMALLOC_H

#include "CoreLib/Compiler/Compiler.h"
#include "CoreLib/Error/ErrorHandling.h"
#include <cstdlib>

namespace rcc
{

RCC_ATTRIBUTE_RETURNS_NONNULL inline void *
safe_malloc (size_t Sz)
{
  void *Result = std::malloc (Sz);
  if (Result == nullptr)
  {
    // It is implementation-defined whether allocation occurs if the space
    // requested is zero (ISO/IEC 9899:2018 7.22.3). Retry, requesting
    // non-zero, if the space requested was zero.
    if (Sz == 0)
    {
      return safe_malloc (1);
    }
    report_bad_alloc_error ("Allocation failed");
  }
  return Result;
}

RCC_ATTRIBUTE_RETURNS_NONNULL inline void *
safe_calloc (size_t Count, size_t Sz)
{
  void *Result = std::calloc (Count, Sz);
  if (Result == nullptr)
  {
    // It is implementation-defined whether allocation occurs if the space
    // requested is zero (ISO/IEC 9899:2018 7.22.3). Retry, requesting
    // non-zero, if the space requested was zero.
    if (Count == 0 || Sz == 0)
    {
      return safe_malloc (1);
    }
    report_bad_alloc_error ("Allocation failed");
  }
  return Result;
}

RCC_ATTRIBUTE_RETURNS_NONNULL inline void *
safe_realloc (void *Ptr, size_t Sz)
{
  void *Result = std::realloc (Ptr, Sz);
  if (Result == nullptr)
  {
    // It is implementation-defined whether allocation occurs if the space
    // requested is zero (ISO/IEC 9899:2018 7.22.3). Retry, requesting
    // non-zero, if the space requested was zero.
    if (Sz == 0)
    {
      return safe_malloc (1);
    }
    report_bad_alloc_error ("Allocation failed");
  }
  return Result;
}

/// Allocate a buffer of memory with the given size and alignment.
///
/// When the compiler supports aligned operator new, this will use it to
/// handle even over-aligned allocations.
///
/// However, this doesn't make any attempt to leverage the fancier techniques
/// like posix_memalign due to portability. It is mostly intended to allow
/// compatibility with platforms that, after aligned allocation was added, use
/// reduced default alignment.
RCC_ABI RCC_ATTRIBUTE_RETURNS_NONNULL RCC_ATTRIBUTE_RETURNS_NOALIAS void *
allocate_buffer (size_t Size, size_t Alignment);

/// Deallocate a buffer of memory with the given size and alignment.
///
/// If supported, this will used the sized delete operator. Also if supported,
/// this will pass the alignment to the delete operator.
///
/// The pointer must have been allocated with the corresponding new operator,
/// most likely using the above helper.
RCC_ABI void
deallocate_buffer (void *Ptr, size_t Size, size_t Alignment);

} // namespace rcc
#endif