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-rw-r--r--libbase/include/core/memory/Alignment.h497
-rw-r--r--libbase/include/core/memory/AllocatorBase.h200
-rw-r--r--libbase/include/core/memory/MemAlloc.h125
3 files changed, 822 insertions, 0 deletions
diff --git a/libbase/include/core/memory/Alignment.h b/libbase/include/core/memory/Alignment.h
new file mode 100644
index 0000000..1391e06
--- /dev/null
+++ b/libbase/include/core/memory/Alignment.h
@@ -0,0 +1,497 @@
+/*
+ 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/>.
+ */
+
+//===-- rcc/Memory/Alignment.h - Useful alignment 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains types to represent alignments.
+// They are instrumented to guarantee some invariants are preserved and prevent
+// invalid manipulations.
+//
+// - Align represents an alignment in bytes, it is always set and always a valid
+// power of two, its minimum value is 1 which means no alignment requirements.
+//
+// - MaybeAlign is an optional type, it may be undefined or set. When it's set
+// you can get the underlying Align type by using the value() method.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LIBBASE_SUPPORT_ALIGNMENT_H_
+#define LIBBASE_SUPPORT_ALIGNMENT_H_
+
+#include "core/math/MathExtras.h"
+#include <cassert>
+#include <optional>
+#ifndef NDEBUG
+#include <string>
+#endif // NDEBUG
+
+namespace libbase
+{
+
+#define ALIGN_CHECK_ISPOSITIVE(decl) \
+ assert (decl > 0 && (#decl " should be defined"))
+
+/// This struct is a compact representation of a valid (non-zero power of two)
+/// alignment.
+/// It is suitable for use as static global constants.
+struct Align
+{
+private:
+ uint8_t ShiftValue = 0; /// The log2 of the required alignment.
+ /// ShiftValue is less than 64 by construction.
+
+ friend struct MaybeAlign;
+ friend unsigned Log2 (Align);
+ friend bool
+ operator== (Align Lhs, Align Rhs);
+ friend bool
+ operator!= (Align Lhs, Align Rhs);
+ friend bool
+ operator<= (Align Lhs, Align Rhs);
+ friend bool
+ operator>= (Align Lhs, Align Rhs);
+ friend bool
+ operator< (Align Lhs, Align Rhs);
+ friend bool
+ operator> (Align Lhs, Align Rhs);
+ friend unsigned
+ encode (struct MaybeAlign A);
+ friend struct MaybeAlign
+ decodeMaybeAlign (unsigned Value);
+
+public:
+ /// Default is byte-aligned.
+ constexpr Align () = default;
+ /// Do not perform checks in case of copy/move construct/assign, because the
+ /// checks have been performed when building `Other`.
+ constexpr Align (const Align &Other) = default;
+ constexpr Align (Align &&Other) = default;
+ constexpr Align &
+ operator= (const Align &Other) = default;
+ constexpr Align &
+ operator= (Align &&Other) = default;
+
+ explicit Align (uint64_t Value)
+ {
+ assert (Value > 0 && "Value must not be 0");
+ assert (libbase::isPowerOf2_64 (Value) && "Alignment is not a power of 2");
+ ShiftValue = Log2_64 (Value);
+ assert (ShiftValue < 64 && "Broken invariant");
+ }
+
+ /// Returns an alignment of `1 << Log2Value` bytes.
+ constexpr static Align
+ fromLog2 (unsigned Log2Value)
+ {
+ assert (Log2Value < 64 && "Alignment exponent is too large");
+ Align Out;
+ Out.ShiftValue = Log2Value;
+ return Out;
+ }
+
+ /// This is a hole in the type system and should not be abused.
+ /// Needed to interact with C for instance.
+ constexpr uint64_t
+ value () const
+ {
+ return uint64_t (1) << ShiftValue;
+ }
+
+ // Returns the previous alignment.
+ Align
+ previous () const
+ {
+ assert (ShiftValue != 0 && "Undefined operation");
+ Align Out;
+ Out.ShiftValue = ShiftValue - 1;
+ return Out;
+ }
+
+ /// Allow constructions of constexpr Align.
+ template <size_t kValue>
+ constexpr static Align
+ Constant ()
+ {
+ return fromLog2 (ConstantLog2<kValue> ());
+ }
+
+ /// Allow constructions of constexpr Align from types.
+ /// Compile time equivalent to Align(alignof(T)).
+ template <typename T>
+ constexpr static Align
+ Of ()
+ {
+ return Constant<std::alignment_of_v<T>> ();
+ }
+};
+
+/// Treats the value 0 as a 1, so Align is always at least 1.
+inline Align
+assumeAligned (uint64_t Value)
+{
+ return Value ? Align (Value) : Align ();
+}
+
+/// This struct is a compact representation of a valid (power of two) or
+/// undefined (0) alignment.
+struct MaybeAlign : std::optional<Align>
+{
+private:
+ using UP = std::optional<Align>;
+
+public:
+ /// Default is undefined.
+ MaybeAlign () = default;
+ /// Do not perform checks in case of copy/move construct/assign, because the
+ /// checks have been performed when building `Other`.
+ MaybeAlign (const MaybeAlign &Other) = default;
+ MaybeAlign &
+ operator= (const MaybeAlign &Other) = default;
+ MaybeAlign (MaybeAlign &&Other) = default;
+ MaybeAlign &
+ operator= (MaybeAlign &&Other) = default;
+
+ constexpr MaybeAlign (std::nullopt_t None) : UP (None)
+ {
+ }
+ constexpr MaybeAlign (Align Value) : UP (Value)
+ {
+ }
+ explicit MaybeAlign (uint64_t Value)
+ {
+ assert ((Value == 0 || libbase::isPowerOf2_64 (Value)) &&
+ "Alignment is neither 0 nor a power of 2");
+ if (Value)
+ {
+ emplace (Value);
+ }
+ }
+
+ /// For convenience, returns a valid alignment or 1 if undefined.
+ Align
+ valueOrOne () const
+ {
+ return value_or (Align ());
+ }
+};
+
+/// Checks that SizeInBytes is a multiple of the alignment.
+inline bool
+isAligned (Align Lhs, uint64_t SizeInBytes)
+{
+ return SizeInBytes % Lhs.value () == 0;
+}
+
+/// Checks that Addr is a multiple of the alignment.
+inline bool
+isAddrAligned (Align Lhs, const void *Addr)
+{
+ return isAligned (Lhs, reinterpret_cast<uintptr_t> (Addr));
+}
+
+/// Returns a multiple of A needed to store `Size` bytes.
+constexpr inline uint64_t
+alignTo (uint64_t Size, Align A)
+{
+ const uint64_t Value = A.value ();
+ // The following line is equivalent to `(Size + Value - 1) / Value * Value`.
+
+ // The division followed by a multiplication can be thought of as a right
+ // shift followed by a left shift which zeros out the extra bits produced in
+ // the bump; `~(Value - 1)` is a mask where all those bits being zeroed out
+ // are just zero.
+
+ // Most compilers can generate this code but the pattern may be missed when
+ // multiple functions gets inlined.
+ return (Size + Value - 1) & ~(Value - 1U);
+}
+
+/// If non-zero \p Skew is specified, the return value will be a minimal integer
+/// that is greater than or equal to \p Size and equal to \p A * N + \p Skew for
+/// some integer N. If \p Skew is larger than \p A, its value is adjusted to '\p
+/// Skew mod \p A'.
+///
+/// Examples:
+/// \code
+/// alignTo(5, Align(8), 7) = 7
+/// alignTo(17, Align(8), 1) = 17
+/// alignTo(~0LL, Align(8), 3) = 3
+/// \endcode
+inline uint64_t
+alignTo (uint64_t Size, Align A, uint64_t Skew)
+{
+ const uint64_t Value = A.value ();
+ Skew %= Value;
+ return alignTo (Size - Skew, A) + Skew;
+}
+
+/// Aligns `Addr` to `Alignment` bytes, rounding up.
+inline uintptr_t
+alignAddr (const void *Addr, Align Alignment)
+{
+ uintptr_t ArithAddr = reinterpret_cast<uintptr_t> (Addr);
+ assert (static_cast<uintptr_t> (ArithAddr + Alignment.value () - 1) >=
+ ArithAddr &&
+ "Overflow");
+ return alignTo (ArithAddr, Alignment);
+}
+
+/// Returns the offset to the next integer (mod 2**64) that is greater than
+/// or equal to \p Value and is a multiple of \p Align.
+inline uint64_t
+offsetToAlignment (uint64_t Value, Align Alignment)
+{
+ return alignTo (Value, Alignment) - Value;
+}
+
+/// Returns the necessary adjustment for aligning `Addr` to `Alignment`
+/// bytes, rounding up.
+inline uint64_t
+offsetToAlignedAddr (const void *Addr, Align Alignment)
+{
+ return offsetToAlignment (reinterpret_cast<uintptr_t> (Addr), Alignment);
+}
+
+/// Returns the log2 of the alignment.
+inline unsigned
+Log2 (Align A)
+{
+ return A.ShiftValue;
+}
+
+/// Returns the alignment that satisfies both alignments.
+/// Same semantic as MinAlign.
+inline Align
+commonAlignment (Align A, uint64_t Offset)
+{
+ return Align (MinAlign (A.value (), Offset));
+}
+
+/// Returns a representation of the alignment that encodes undefined as 0.
+inline unsigned
+encode (MaybeAlign A)
+{
+ return A ? A->ShiftValue + 1 : 0;
+}
+
+/// Dual operation of the encode function above.
+inline MaybeAlign
+decodeMaybeAlign (unsigned Value)
+{
+ if (Value == 0)
+ {
+ return MaybeAlign ();
+ }
+ Align Out;
+ Out.ShiftValue = Value - 1;
+ return Out;
+}
+
+/// Returns a representation of the alignment, the encoded value is positive by
+/// definition.
+inline unsigned
+encode (Align A)
+{
+ return encode (MaybeAlign (A));
+}
+
+/// Comparisons between Align and scalars. Rhs must be positive.
+inline bool
+operator== (Align Lhs, uint64_t Rhs)
+{
+ ALIGN_CHECK_ISPOSITIVE (Rhs);
+ return Lhs.value () == Rhs;
+}
+inline bool
+operator!= (Align Lhs, uint64_t Rhs)
+{
+ ALIGN_CHECK_ISPOSITIVE (Rhs);
+ return Lhs.value () != Rhs;
+}
+inline bool
+operator<= (Align Lhs, uint64_t Rhs)
+{
+ ALIGN_CHECK_ISPOSITIVE (Rhs);
+ return Lhs.value () <= Rhs;
+}
+inline bool
+operator>= (Align Lhs, uint64_t Rhs)
+{
+ ALIGN_CHECK_ISPOSITIVE (Rhs);
+ return Lhs.value () >= Rhs;
+}
+inline bool
+operator< (Align Lhs, uint64_t Rhs)
+{
+ ALIGN_CHECK_ISPOSITIVE (Rhs);
+ return Lhs.value () < Rhs;
+}
+inline bool
+operator> (Align Lhs, uint64_t Rhs)
+{
+ ALIGN_CHECK_ISPOSITIVE (Rhs);
+ return Lhs.value () > Rhs;
+}
+
+/// Comparisons operators between Align.
+inline bool
+operator== (Align Lhs, Align Rhs)
+{
+ return Lhs.ShiftValue == Rhs.ShiftValue;
+}
+inline bool
+operator!= (Align Lhs, Align Rhs)
+{
+ return Lhs.ShiftValue != Rhs.ShiftValue;
+}
+inline bool
+operator<= (Align Lhs, Align Rhs)
+{
+ return Lhs.ShiftValue <= Rhs.ShiftValue;
+}
+inline bool
+operator>= (Align Lhs, Align Rhs)
+{
+ return Lhs.ShiftValue >= Rhs.ShiftValue;
+}
+inline bool
+operator< (Align Lhs, Align Rhs)
+{
+ return Lhs.ShiftValue < Rhs.ShiftValue;
+}
+inline bool
+operator> (Align Lhs, Align Rhs)
+{
+ return Lhs.ShiftValue > Rhs.ShiftValue;
+}
+
+// Don't allow relational comparisons with MaybeAlign.
+bool
+operator<= (Align Lhs, MaybeAlign Rhs) = delete;
+bool
+operator>= (Align Lhs, MaybeAlign Rhs) = delete;
+bool
+operator< (Align Lhs, MaybeAlign Rhs) = delete;
+bool
+operator> (Align Lhs, MaybeAlign Rhs) = delete;
+
+bool
+operator<= (MaybeAlign Lhs, Align Rhs) = delete;
+bool
+operator>= (MaybeAlign Lhs, Align Rhs) = delete;
+bool
+operator< (MaybeAlign Lhs, Align Rhs) = delete;
+bool
+operator> (MaybeAlign Lhs, Align Rhs) = delete;
+
+bool
+operator<= (MaybeAlign Lhs, MaybeAlign Rhs) = delete;
+bool
+operator>= (MaybeAlign Lhs, MaybeAlign Rhs) = delete;
+bool
+operator< (MaybeAlign Lhs, MaybeAlign Rhs) = delete;
+bool
+operator> (MaybeAlign Lhs, MaybeAlign Rhs) = delete;
+
+// Allow equality comparisons between Align and MaybeAlign.
+inline bool
+operator== (MaybeAlign Lhs, Align Rhs)
+{
+ return Lhs && *Lhs == Rhs;
+}
+inline bool
+operator!= (MaybeAlign Lhs, Align Rhs)
+{
+ return !(Lhs == Rhs);
+}
+inline bool
+operator== (Align Lhs, MaybeAlign Rhs)
+{
+ return Rhs == Lhs;
+}
+inline bool
+operator!= (Align Lhs, MaybeAlign Rhs)
+{
+ return !(Rhs == Lhs);
+}
+// Allow equality comparisons with MaybeAlign.
+inline bool
+operator== (MaybeAlign Lhs, MaybeAlign Rhs)
+{
+ return (Lhs && Rhs && (*Lhs == *Rhs)) || (!Lhs && !Rhs);
+}
+inline bool
+operator!= (MaybeAlign Lhs, MaybeAlign Rhs)
+{
+ return !(Lhs == Rhs);
+}
+// Allow equality comparisons with std::nullopt.
+inline bool
+operator== (MaybeAlign Lhs, std::nullopt_t)
+{
+ return !bool (Lhs);
+}
+inline bool
+operator!= (MaybeAlign Lhs, std::nullopt_t)
+{
+ return bool (Lhs);
+}
+inline bool
+operator== (std::nullopt_t, MaybeAlign Rhs)
+{
+ return !bool (Rhs);
+}
+inline bool
+operator!= (std::nullopt_t, MaybeAlign Rhs)
+{
+ return bool (Rhs);
+}
+
+#ifndef NDEBUG
+// For usage in LLVM_DEBUG macros.
+inline std::string
+DebugStr (const Align &A)
+{
+ return std::to_string (A.value ());
+}
+// For usage in LLVM_DEBUG macros.
+inline std::string
+DebugStr (const MaybeAlign &MA)
+{
+ if (MA)
+ {
+ return std::to_string (MA->value ());
+ }
+ return "None";
+}
+#endif // NDEBUG
+
+#undef ALIGN_CHECK_ISPOSITIVE
+
+} // namespace libbase
+
+#endif // LIBBASE_SUPPORT_ALIGNMENT_H_
diff --git a/libbase/include/core/memory/AllocatorBase.h b/libbase/include/core/memory/AllocatorBase.h
new file mode 100644
index 0000000..af6f5ca
--- /dev/null
+++ b/libbase/include/core/memory/AllocatorBase.h
@@ -0,0 +1,200 @@
+/*
+ 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/>.
+ */
+
+//===- AllocatorBase.h - Simple memory allocation abstraction ---*- 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 MallocAllocator. MallocAllocator conforms to the LLVM
+/// "Allocator" concept which consists of an Allocate method accepting a size
+/// and alignment, and a Deallocate accepting a pointer and size. Further, the
+/// LLVM "Allocator" concept has overloads of Allocate and Deallocate for
+/// setting size and alignment based on the final type. These overloads are
+/// typically provided by a base class template \c AllocatorBase.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LIBBASE_SUPPORT_ALLOCATORBASE_H
+#define LIBBASE_SUPPORT_ALLOCATORBASE_H
+
+#ifdef _MSC_VER
+#define LIBBASE_ALLOCATORHOLDER_EMPTYBASE __declspec (empty_bases)
+#else
+#define LIBBASE_ALLOCATORHOLDER_EMPTYBASE
+#endif // _MSC_VER
+
+#include "core/compiler/Compiler.h"
+#include "core/memory/MemAlloc.h"
+#include <type_traits>
+#include <utility>
+
+namespace libbase
+{
+
+/// CRTP base class providing obvious overloads for the core \c
+/// Allocate() methods of LLVM-style allocators.
+///
+/// This base class both documents the full public interface exposed by all
+/// LLVM-style allocators, and redirects all of the overloads to a single core
+/// set of methods which the derived class must define.
+template <typename DerivedT> class AllocatorBase
+{
+public:
+ /// Allocate \a Size bytes of \a Alignment aligned memory. This method
+ /// must be implemented by \c DerivedT.
+ void *
+ Allocate (size_t Size, size_t Alignment)
+ {
+#ifdef __clang__
+ static_assert (static_cast<void *(AllocatorBase::*) (size_t, size_t)> (
+ &AllocatorBase::Allocate) !=
+ static_cast<void *(DerivedT::*) (size_t, size_t)> (
+ &DerivedT::Allocate),
+ "Class derives from AllocatorBase without implementing the "
+ "core Allocate(size_t, size_t) overload!");
+#endif
+ return static_cast<DerivedT *> (this)->Allocate (Size, Alignment);
+ }
+
+ /// Deallocate \a Ptr to \a Size bytes of memory allocated by this
+ /// allocator.
+ void
+ Deallocate (const void *Ptr, size_t Size, size_t Alignment)
+ {
+#ifdef __clang__
+ static_assert (
+ static_cast<void (AllocatorBase::*) (const void *, size_t, size_t)> (
+ &AllocatorBase::Deallocate) !=
+ static_cast<void (DerivedT::*) (const void *, size_t, size_t)> (
+ &DerivedT::Deallocate),
+ "Class derives from AllocatorBase without implementing the "
+ "core Deallocate(void *) overload!");
+#endif
+ return static_cast<DerivedT *> (this)->Deallocate (Ptr, Size, Alignment);
+ }
+
+ // The rest of these methods are helpers that redirect to one of the above
+ // core methods.
+
+ /// Allocate space for a sequence of objects without constructing them.
+ template <typename T>
+ T *
+ Allocate (size_t Num = 1)
+ {
+ return static_cast<T *> (Allocate (Num * sizeof (T), alignof (T)));
+ }
+
+ /// Deallocate space for a sequence of objects without constructing them.
+ template <typename T>
+ std::enable_if_t<!std::is_same_v<std::remove_cv_t<T>, void>, void>
+ Deallocate (T *Ptr, size_t Num = 1)
+ {
+ Deallocate (static_cast<const void *> (Ptr), Num * sizeof (T), alignof (T));
+ }
+};
+
+class MallocAllocator : public AllocatorBase<MallocAllocator>
+{
+public:
+ void
+ Reset ()
+ {
+ }
+
+ LIBBASE_ATTRIBUTE_RETURNS_NONNULL void *
+ Allocate (size_t Size, size_t Alignment)
+ {
+ return allocate_buffer (Size, Alignment);
+ }
+
+ // Pull in base class overloads.
+ using AllocatorBase<MallocAllocator>::Allocate;
+
+ void
+ Deallocate (const void *Ptr, size_t Size, size_t Alignment)
+ {
+ deallocate_buffer (const_cast<void *> (Ptr), Size, Alignment);
+ }
+
+ // Pull in base class overloads.
+ using AllocatorBase<MallocAllocator>::Deallocate;
+
+ void
+ PrintStats () const
+ {
+ }
+};
+
+namespace detail
+{
+
+template <typename Alloc> class AllocatorHolder : Alloc
+{
+public:
+ AllocatorHolder () = default;
+ AllocatorHolder (const Alloc &A) : Alloc (A)
+ {
+ }
+ AllocatorHolder (Alloc &&A) : Alloc (std::move (A))
+ {
+ }
+ Alloc &
+ getAllocator ()
+ {
+ return *this;
+ }
+ const Alloc &
+ getAllocator () const
+ {
+ return *this;
+ }
+};
+
+template <typename Alloc> class AllocatorHolder<Alloc &>
+{
+ Alloc &A;
+
+public:
+ AllocatorHolder (Alloc &A) : A (A)
+ {
+ }
+ Alloc &
+ getAllocator ()
+ {
+ return A;
+ }
+ const Alloc &
+ getAllocator () const
+ {
+ return A;
+ }
+};
+
+} // namespace detail
+
+} // namespace libbase
+
+#endif // LIBBASE_SUPPORT_ALLOCATORBASE_H
diff --git a/libbase/include/core/memory/MemAlloc.h b/libbase/include/core/memory/MemAlloc.h
new file mode 100644
index 0000000..be7828e
--- /dev/null
+++ b/libbase/include/core/memory/MemAlloc.h
@@ -0,0 +1,125 @@
+/*
+ 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 LIBBASE_SUPPORT_MEMALLOC_H
+#define LIBBASE_SUPPORT_MEMALLOC_H
+
+#include "core/compiler/Compiler.h"
+#include "core/error/ErrorHandling.h"
+#include <cstdlib>
+
+namespace libbase
+{
+
+LIBBASE_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;
+}
+
+LIBBASE_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;
+}
+
+LIBBASE_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.
+LIBBASE_ABI
+ LIBBASE_ATTRIBUTE_RETURNS_NONNULL LIBBASE_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.
+LIBBASE_ABI void
+deallocate_buffer (void *Ptr, size_t Size, size_t Alignment);
+
+} // namespace libbase
+#endif