improve layout of page for x64

CMakeLists.txt

@@ -91,7 +91,7 @@ if(CMAKE_C_COMPILER_ID MATCHES "AppleClang|Clang|GNU")
   if(CMAKE_C_COMPILER_ID MATCHES "GNU")
     list(APPEND mi_cflags -Wno-invalid-memory-model)
     list(APPEND mi_cflags -fvisibility=hidden)
-    list(APPEND mi_cflags -fbranch-target-load-optimize )
+    list(APPEND mi_cflags -fbranch-target-load-optimize)
   endif()
 endif()
 

include/mimalloc-types.h

@@ -182,7 +182,7 @@ typedef struct mi_page_s {
 
 // improve page index calculation
 #if (MI_INTPTR_SIZE==8 && MI_SECURE==0)
-  void*                 padding[1];        // 12 words on 64-bit
+  // void*                 padding[1];        // 12 words on 64-bit
 #elif MI_INTPTR_SIZE==4
   // void*                 padding[1];         // 12 words on 32-bit
 #endif

src/alloc.c

@@ -225,7 +225,7 @@ void mi_free(void* p) mi_attr_noexcept
   }
 #endif
 
-  mi_page_t* page = _mi_segment_page_of(segment, p);
+  mi_page_t* const page = _mi_segment_page_of(segment, p);
 
 #if (MI_STAT>1)
   mi_heap_t* heap = mi_heap_get_default();
@@ -236,7 +236,7 @@ void mi_free(void* p) mi_attr_noexcept
   // huge page stat is accounted for in `_mi_page_retire`
 #endif
 
-  uintptr_t tid = _mi_thread_id();
+  const uintptr_t tid = _mi_thread_id();
   if (mi_likely(tid == page->flags)) {  // if equal, the thread id matches and it is not a full page, nor has aligned blocks
     // local, and not full or aligned
     mi_block_t* block = (mi_block_t*)p;

src/init.c

@@ -21,7 +21,7 @@ const mi_page_t _mi_page_empty = {
   NULL, 0, 0,
   0, NULL, NULL, NULL
   #if (MI_INTPTR_SIZE==8 && MI_SECURE==0)
-  , { NULL } 
+  // , { NULL }
   #endif
 };