[libc++][NFC] Move __memory/aligned_alloc.h into src/ (#166172)

This header is only ever used inside `src/`, so we might as well move it
there. As a drive-by this also removes some dead code.

Author: philnik777

libcxx/include/CMakeLists.txt

@@ -569,7 +569,6 @@ set(files
   __mdspan/mdspan.h
   __memory/addressof.h
   __memory/align.h
-  __memory/aligned_alloc.h
   __memory/allocate_at_least.h
   __memory/allocation_guard.h
   __memory/allocator.h

libcxx/include/__config

@@ -495,27 +495,6 @@ typedef __char32_t char32_t;
 #    define _LIBCPP_HAS_ALIGNED_ALLOCATION 1
 #  endif
 
-// It is not yet possible to use aligned_alloc() on all Apple platforms since
-// 10.15 was the first version to ship an implementation of aligned_alloc().
-#  if defined(__APPLE__)
-#    if (defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) &&                                                     \
-         __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101500) ||                                                    \
-        (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) &&                                                    \
-         __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 130000) ||                                                   \
-        (defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__) &&                                                     \
-         __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ < 60000) ||                                                     \
-        (defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__) && __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ < 130000)
-#      define _LIBCPP_HAS_C11_ALIGNED_ALLOC 0
-#    else
-#      define _LIBCPP_HAS_C11_ALIGNED_ALLOC 1
-#    endif
-#  elif defined(__ANDROID__) && __ANDROID_API__ < 28
-// Android only provides aligned_alloc when targeting API 28 or higher.
-#    define _LIBCPP_HAS_C11_ALIGNED_ALLOC 0
-#  else
-#    define _LIBCPP_HAS_C11_ALIGNED_ALLOC 1
-#  endif
-
 #  if defined(__APPLE__) || defined(__FreeBSD__)
 #    define _LIBCPP_WCTYPE_IS_MASK
 #  endif

libcxx/include/module.modulemap.in

@@ -1628,7 +1628,6 @@ module std [system] {
   module memory {
     module addressof                          { header "__memory/addressof.h" }
     module align                              { header "__memory/align.h" }
-    module aligned_alloc                      { header "__memory/aligned_alloc.h" }
     module allocate_at_least                  { header "__memory/allocate_at_least.h" }
     module allocation_guard                   { header "__memory/allocation_guard.h" }
     module allocator {

libcxx/include/__memory/aligned_alloc.h renamed to libcxx/src/include/aligned_alloc.h

@@ -6,8 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef _LIBCPP___MEMORY_ALIGNED_ALLOC_H
-#define _LIBCPP___MEMORY_ALIGNED_ALLOC_H
+#ifndef _LIBCPP_SRC_ALIGNED_ALLOC_H
+#define _LIBCPP_SRC_ALIGNED_ALLOC_H
 
 #include <__config>
 #include <cstdlib>
@@ -29,7 +29,9 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 inline _LIBCPP_HIDE_FROM_ABI void* __libcpp_aligned_alloc(std::size_t __alignment, std::size_t __size) {
 #  if defined(_LIBCPP_MSVCRT_LIKE)
   return ::_aligned_malloc(__size, __alignment);
-#  elif _LIBCPP_STD_VER >= 17 && _LIBCPP_HAS_C11_ALIGNED_ALLOC
+
+// Android only provides aligned_alloc when targeting API 28 or higher.
+#  elif !defined(__ANDROID__) || __ANDROID_API__ >= 28
   // aligned_alloc() requires that __size is a multiple of __alignment,
   // but for C++ [new.delete.general], only states "if the value of an
   // alignment argument passed to any of these functions is not a valid
@@ -60,4 +62,4 @@ inline _LIBCPP_HIDE_FROM_ABI void __libcpp_aligned_free(void* __ptr) {
 
 _LIBCPP_END_NAMESPACE_STD
 
-#endif // _LIBCPP___MEMORY_ALIGNED_ALLOC_H
+#endif // _LIBCPP_SRC_ALIGNED_ALLOC_H

libcxx/test/libcxx/language.support/support.dynamic/libcpp_deallocate.sh.cpp

@@ -21,6 +21,8 @@
 // GCC doesn't support the aligned-allocation flags.
 // XFAIL: gcc
 
+// ADDITIONAL_COMPILE_FLAGS: -I %{libcxx-dir}/src -Wno-macro-redefined
+
 // RUN: %{build} -faligned-allocation -fsized-deallocation
 // RUN: %{run}
 // RUN: %{build} -faligned-allocation -fno-sized-deallocation -DNO_SIZE
@@ -36,10 +38,7 @@
 
 #include "test_macros.h"
 
-TEST_DIAGNOSTIC_PUSH
-TEST_CLANG_DIAGNOSTIC_IGNORED("-Wprivate-header")
-#include <__memory/aligned_alloc.h>
-TEST_DIAGNOSTIC_POP
+#include "include/aligned_alloc.h"
 
 struct alloc_stats {
   alloc_stats() { reset(); }

libcxxabi/src/fallback_malloc.cpp

@@ -16,7 +16,7 @@
 #endif
 #endif
 
-#include <__memory/aligned_alloc.h>
+#include "include/aligned_alloc.h" // from libc++
 #include <__assert>
 #include <stdlib.h> // for malloc, calloc, free
 #include <string.h> // for memset

libcxxabi/src/stdlib_new_delete.cpp

@@ -8,8 +8,8 @@
 
 #include "__cxxabi_config.h"
 #include "abort_message.h"
+#include "include/aligned_alloc.h"        // from libc++
 #include "include/overridable_function.h" // from libc++
-#include <__memory/aligned_alloc.h>
 #include <cstddef>
 #include <cstdlib>
 #include <new>