[libcxx-commits] [libcxx] c778f6c - [libc++] Clean up logic around aligned/sized allocation and deallocation

[Louis Dionne via libcxx-commits]

Author: Louis Dionne
Date: 2020-10-09T12:43:28-04:00
New Revision: c778f6c4f9d511023c0d71b9e14a90e60445d314

URL: https://github.com/llvm/llvm-project/commit/c778f6c4f9d511023c0d71b9e14a90e60445d314
DIFF: https://github.com/llvm/llvm-project/commit/c778f6c4f9d511023c0d71b9e14a90e60445d314.diff

LOG: [libc++] Clean up logic around aligned/sized allocation and deallocation

Due to the need to support compilers that implement builtin operator
new/delete but not their align_val_t overloaded versions, there was a
lot of complexity. By assuming that a compiler that supports the builtin
new/delete operators also supports their align_val_t overloads, the code
can be simplified quite a bit.

Differential Revision: https://reviews.llvm.org/D88301

Added: 
    

Modified: 
    libcxx/include/__config
    libcxx/include/new

Removed: 
    


################################################################################
diff  --git a/libcxx/include/__config b/libcxx/include/__config
index b51261132ee8..8d2ab2e51b11 100644
--- a/libcxx/include/__config
+++ b/libcxx/include/__config
@@ -868,10 +868,6 @@ typedef unsigned int   char32_t;
 #  define _LIBCPP_EXPLICIT
 #endif
 
-#if !__has_builtin(__builtin_operator_new) || !__has_builtin(__builtin_operator_delete)
-#define _LIBCPP_HAS_NO_BUILTIN_OPERATOR_NEW_DELETE
-#endif
-
 #ifdef _LIBCPP_HAS_NO_STRONG_ENUMS
 #  define _LIBCPP_DECLARE_STRONG_ENUM(x) struct _LIBCPP_TYPE_VIS x { enum __lx
 #  define _LIBCPP_DECLARE_STRONG_ENUM_EPILOG(x) \

diff  --git a/libcxx/include/new b/libcxx/include/new
index dbfdab9abe4d..e21c22bc2ed1 100644
--- a/libcxx/include/new
+++ b/libcxx/include/new
@@ -117,11 +117,6 @@ void  operator delete[](void* ptr, void*) noexcept;
 # define _LIBCPP_HAS_NO_SIZED_DEALLOCATION
 #endif
 
-#if !__has_builtin(__builtin_operator_new) || \
-   __has_builtin(__builtin_operator_new) < 201802L
-#define _LIBCPP_HAS_NO_BUILTIN_OVERLOADED_OPERATOR_NEW_DELETE
-#endif
-
 namespace std  // purposefully not using versioning namespace
 {
 
@@ -234,80 +229,54 @@ _LIBCPP_CONSTEXPR inline _LIBCPP_INLINE_VISIBILITY bool __is_overaligned_for_new
 #endif
 }
 
-inline _LIBCPP_INLINE_VISIBILITY
-void *__libcpp_allocate(size_t __size, size_t __align) {
-#ifndef _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
-  if (__is_overaligned_for_new(__align)) {
-    const align_val_t __align_val = static_cast<align_val_t>(__align);
-# ifdef _LIBCPP_HAS_NO_BUILTIN_OVERLOADED_OPERATOR_NEW_DELETE
-    return ::operator new(__size, __align_val);
-# else
-    return __builtin_operator_new(__size, __align_val);
-# endif
-  }
+template <class ..._Args>
+_LIBCPP_INLINE_VISIBILITY
+void* __libcpp_operator_new(_Args ...__args) {
+#if __has_builtin(__builtin_operator_new) && __has_builtin(__builtin_operator_delete)
+  return __builtin_operator_new(__args...);
 #else
-  ((void)__align);
-#endif
-#ifdef _LIBCPP_HAS_NO_BUILTIN_OPERATOR_NEW_DELETE
-  return ::operator new(__size);
-#else
-  return __builtin_operator_new(__size);
+  return ::operator new(__args...);
 #endif
 }
 
-struct _DeallocateCaller {
-  template <class _A1, class _A2>
-  static inline void __do_call(void *__ptr, _A1 __a1, _A2 __a2) {
-#if defined(_LIBCPP_HAS_NO_BUILTIN_OPERATOR_NEW_DELETE) || \
-    defined(_LIBCPP_HAS_NO_BUILTIN_OVERLOADED_OPERATOR_NEW_DELETE)
-    return ::operator delete(__ptr, __a1, __a2);
+template <class ..._Args>
+_LIBCPP_INLINE_VISIBILITY
+void __libcpp_operator_delete(_Args ...__args) {
+#if __has_builtin(__builtin_operator_new) && __has_builtin(__builtin_operator_delete)
+  __builtin_operator_delete(__args...);
 #else
-    return __builtin_operator_delete(__ptr, __a1, __a2);
+  ::operator delete(__args...);
 #endif
-  }
+}
 
-  template <class _A1>
-  static inline void __do_call(void *__ptr, _A1 __a1) {
-#if defined(_LIBCPP_HAS_NO_BUILTIN_OPERATOR_NEW_DELETE) || \
-    defined(_LIBCPP_HAS_NO_BUILTIN_OVERLOADED_OPERATOR_NEW_DELETE)
-    return ::operator delete(__ptr, __a1);
-#else
-    return __builtin_operator_delete(__ptr, __a1);
-#endif
+inline _LIBCPP_INLINE_VISIBILITY
+void *__libcpp_allocate(size_t __size, size_t __align) {
+#ifndef _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
+  if (__is_overaligned_for_new(__align)) {
+    const align_val_t __align_val = static_cast<align_val_t>(__align);
+    return __libcpp_operator_new(__size, __align_val);
   }
-
-  static inline void __do_call(void *__ptr) {
-#ifdef _LIBCPP_HAS_NO_BUILTIN_OPERATOR_NEW_DELETE
-    return ::operator delete(__ptr);
-#else
-    return __builtin_operator_delete(__ptr);
 #endif
-  }
 
-  static inline void __do_deallocate_handle_size(void *__ptr, size_t __size) {
-#ifdef _LIBCPP_HAS_NO_SIZED_DEALLOCATION
-    ((void)__size);
-    return __do_call(__ptr);
-#else
-    return __do_call(__ptr, __size);
-#endif
-  }
+  (void)__align;
+  return __libcpp_operator_new(__size);
+}
 
-#ifndef _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
-  static inline void __do_deallocate_handle_size(void *__ptr, size_t __size, align_val_t __align) {
+template <class ..._Args>
+_LIBCPP_INLINE_VISIBILITY
+void __do_deallocate_handle_size(void *__ptr, size_t __size, _Args ...__args) {
 #ifdef _LIBCPP_HAS_NO_SIZED_DEALLOCATION
-    ((void)__size);
-    return __do_call(__ptr, __align);
+  (void)__size;
+  return __libcpp_operator_delete(__ptr, __args...);
 #else
-    return __do_call(__ptr, __size, __align);
-#endif
-  }
+  return __libcpp_operator_delete(__ptr, __size, __args...);
 #endif
+}
 
-  static inline _LIBCPP_INLINE_VISIBILITY
-  void __do_deallocate_handle_size_align(void *__ptr, size_t __size, size_t __align) {
+inline _LIBCPP_INLINE_VISIBILITY
+void __libcpp_deallocate(void* __ptr, size_t __size, size_t __align) {
 #if defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION)
-    ((void)__align);
+    (void)__align;
     return __do_deallocate_handle_size(__ptr, __size);
 #else
     if (__is_overaligned_for_new(__align)) {
@@ -317,31 +286,20 @@ struct _DeallocateCaller {
       return __do_deallocate_handle_size(__ptr, __size);
     }
 #endif
-  }
+}
 
-  static inline _LIBCPP_INLINE_VISIBILITY
-  void __do_deallocate_handle_align(void *__ptr, size_t __align) {
+inline _LIBCPP_INLINE_VISIBILITY void __libcpp_deallocate_unsized(void* __ptr, size_t __align) {
 #if defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION)
-    ((void)__align);
-    return __do_call(__ptr);
+    (void)__align;
+    return __libcpp_operator_delete(__ptr);
 #else
     if (__is_overaligned_for_new(__align)) {
       const align_val_t __align_val = static_cast<align_val_t>(__align);
-      return __do_call(__ptr, __align_val);
+      return __libcpp_operator_delete(__ptr, __align_val);
     } else {
-      return __do_call(__ptr);
+      return __libcpp_operator_delete(__ptr);
     }
 #endif
-  }
-};
-
-inline _LIBCPP_INLINE_VISIBILITY
-void __libcpp_deallocate(void* __ptr, size_t __size, size_t __align) {
-  _DeallocateCaller::__do_deallocate_handle_size_align(__ptr, __size, __align);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY void __libcpp_deallocate_unsized(void* __ptr, size_t __align) {
-  _DeallocateCaller::__do_deallocate_handle_align(__ptr, __align);
 }
 
 template <class _Tp>