Add a redirection layer for small alloc functions.

Author: mjp41

CMakeLists.txt

@@ -169,6 +169,19 @@ if(CONST_QUALIFIED_MALLOC_USABLE_SIZE)
 endif()
 
 
+# Build a redirection layer for all sizes that are a multiple of 
+# 16bytes up to 1024.
+add_executable(generate src/redirect/generate.cc)
+target_link_libraries(generate snmalloc_lib)
+add_custom_target(generated ALL 
+  COMMAND generate ${CMAKE_CURRENT_BINARY_DIR}/generated.cc
+  BYPRODUCTS ${CMAKE_CURRENT_BINARY_DIR}/generated.cc
+  )
+add_library(redirect_small STATIC src/redirect/redirect.cc)
+target_link_libraries(redirect_small snmalloc_lib)
+target_include_directories(redirect_small PRIVATE ${CMAKE_CURRENT_BINARY_DIR})
+
+
 # To build with just the header library target define SNMALLOC_ONLY_HEADER_LIBRARY
 # in containing Cmake file.
 if(NOT DEFINED SNMALLOC_ONLY_HEADER_LIBRARY)

src/mem/alloc.h

@@ -1250,7 +1250,6 @@ namespace snmalloc
       small_dealloc_offseted_slow(super, p, slab->get_meta().sizeclass);
     }
 
-
     SNMALLOC_FAST_PATH void small_dealloc_offseted_inner(
       Superslab* super, void* p, sizeclass_t sizeclass)
     {

src/mem/sizeclass.h

@@ -20,7 +20,8 @@ namespace snmalloc
   constexpr static size_t
   sizeclass_to_inverse_cache_friendly_mask(sizeclass_t sc);
   constexpr static uint16_t medium_slab_free(sizeclass_t sizeclass);
-  template<bool ASSUME_SMALL = false> static sizeclass_t size_to_sizeclass(size_t size);
+  template<bool ASSUME_SMALL = false>
+  static sizeclass_t size_to_sizeclass(size_t size);
 
   constexpr static inline sizeclass_t size_to_sizeclass_const(size_t size)
   {

src/mem/sizeclasstable.h

@@ -110,7 +110,7 @@ namespace snmalloc
     return sizeclass_metadata.inverse_cache_friendly_mask[sizeclass];
   }
 
-  template <bool ASSUME_SMALL>
+  template<bool ASSUME_SMALL>
   static inline sizeclass_t size_to_sizeclass(size_t size)
   {
     if ((size - 1) <= (SLAB_SIZE - 1) || ASSUME_SMALL)

src/override/malloc.cc

@@ -72,14 +72,16 @@ extern "C"
   SNMALLOC_EXPORT
   void SNMALLOC_NAME_MANGLE(free_local_small)(void* ptr)
   {
-    if (Alloc::small_local_dealloc(ptr)) return;
+    if (Alloc::small_local_dealloc(ptr))
+      return;
     ThreadAlloc::get_noncachable()->small_local_dealloc_slow(ptr);
   }
 
   SNMALLOC_EXPORT
   void* SNMALLOC_NAME_MANGLE(malloc_small)(size_t size)
   {
-    return ThreadAlloc::get_noncachable()->small_alloc<NoZero, YesReserve>(size);
+    return ThreadAlloc::get_noncachable()->small_alloc<NoZero, YesReserve>(
+      size);
   }
 
   SNMALLOC_EXPORT
@@ -88,6 +90,12 @@ extern "C"
     return ThreadAlloc::get_noncachable()->small_alloc<NoZero, YesReserve>(64);
   }
 
+  SNMALLOC_EXPORT
+  void* SNMALLOC_NAME_MANGLE(malloc_small_63)()
+  {
+    return ThreadAlloc::get_noncachable()->small_alloc<NoZero, YesReserve>(63);
+  }
+
   SNMALLOC_EXPORT
   size_t SNMALLOC_NAME_MANGLE(malloc_usable_size)(
     MALLOC_USABLE_SIZE_QUALIFIER void* ptr)

src/test/func/malloc/malloc.cc

@@ -131,7 +131,7 @@ int main(int argc, char** argv)
 
   constexpr int SUCCESS = 0;
 
-  for (size_t i = 1; i < SLAB_SIZE; i+=16)
+  for (size_t i = 1; i < SLAB_SIZE; i += 16)
   {
     test_local(i);
   }