[libc++] Move non operator new definitions outside of new.cpp

[ldionne]

Summary

This makes it such that new.cpp contains only the definitions of
operator new and operator delete, like its libc++abi counterpart.

[yronglin]

libcxx/src/new_helpers.cpp

25

Nit: Should we use std:: in new code?

[Mordante]

LGTM, but I have some remarks.

libcxx/src/new.cpp

10

Is this include still needed?

libcxx/src/new_helpers.cpp

25

We should, but this is moved. (I still like to fix it)

[ldionne]

libcxx/src/new.cpp

10

Yes, we use std::malloc.

[ldionne]

Address comments and rebase.

libcxx/src/CMakeLists.txt

set(LIBCXX_SOURCES
   include/to_chars_floating_point.h
   legacy_pointer_safety.cpp
   memory.cpp
   memory_resource.cpp
   mutex.cpp
   mutex_destructor.cpp
   new.cpp
   new_handler.cpp
+  new_helpers.cpp
   optional.cpp
   random_shuffle.cpp
   ryu/d2fixed.cpp
   ryu/d2s.cpp
   ryu/f2s.cpp
   shared_mutex.cpp
   stdexcept.cpp
   string.cpp

libcxx/src/new.cpp

 //===----------------------------------------------------------------------===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 
 #include <__memory/aligned_alloc.h>
 #include <cstdlib>
 #include <new>
 
-namespace std
-{
-
-#ifndef __GLIBCXX__
-const nothrow_t nothrow{};
-#endif
-
-#ifndef LIBSTDCXX
-
-void
-__throw_bad_alloc()
-{
-#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
-    throw bad_alloc();
-#else
-    _VSTD::abort();
-#endif
-}
-
-#endif // !LIBSTDCXX
-
-}  // std
-
 #if !defined(__GLIBCXX__) &&                                                   \
     !defined(_LIBCPP_ABI_VCRUNTIME) &&      \
     !defined(_LIBCPP_DISABLE_NEW_DELETE_DEFINITIONS)
 
 // The code below is copied as-is into libc++abi's libcxxabi/src/stdlib_new_delete.cpp
 // file. The version in this file is the canonical one.
 
 // ------------------ BEGIN COPY ------------------

libcxx/src/new_helpers.cpp

+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include <cstdlib>
+#include <new>
+
+namespace std { // purposefully not versioned
+
+#ifndef __GLIBCXX__
+const nothrow_t nothrow{};
+#endif
+
+#ifndef LIBSTDCXX
+
+void __throw_bad_alloc() {
+#  ifndef _LIBCPP_HAS_NO_EXCEPTIONS
+  throw bad_alloc();
+#  else
+  std::abort();
+#  endif
+}
+
+#endif // !LIBSTDCXX
+
+} // namespace std