Merge branch 'jj1bdx-19.0-rc2-hipemmap/PR-1094'

erts/emulator/sys/common/erl_mmap.c

@@ -1334,9 +1334,17 @@ os_mremap(void *ptr, UWord old_size, UWord new_size, int try_superalign)
 #define ERTS_MMAP_RESERVE_PROT_EXEC	(ERTS_MMAP_PROT_EXEC)
 #define ERTS_MMAP_RESERVE_FLAGS		(ERTS_MMAP_FLAGS|MAP_FIXED)
 #define ERTS_MMAP_UNRESERVE_PROT	(PROT_NONE)
+#if defined(__FreeBSD__)
+#define ERTS_MMAP_UNRESERVE_FLAGS	(ERTS_MMAP_FLAGS|MAP_FIXED)
+#else
 #define ERTS_MMAP_UNRESERVE_FLAGS	(ERTS_MMAP_FLAGS|MAP_NORESERVE|MAP_FIXED)
+#endif /* __FreeBSD__ */
 #define ERTS_MMAP_VIRTUAL_PROT		(PROT_NONE)
+#if defined(__FreeBSD__)
+#define ERTS_MMAP_VIRTUAL_FLAGS		(ERTS_MMAP_FLAGS)
+#else
 #define ERTS_MMAP_VIRTUAL_FLAGS		(ERTS_MMAP_FLAGS|MAP_NORESERVE)
+#endif /* __FreeBSD__ */
 
 static int
 os_reserve_physical(char *ptr, UWord size, int exec)

erts/emulator/sys/common/erl_mmap.h

@@ -38,7 +38,17 @@
 #  if HAVE_MREMAP
 #    define ERTS_HAVE_OS_MREMAP 1
 #  endif
-#  if defined(MAP_FIXED) && defined(MAP_NORESERVE)
+/*
+ * MAP_NORESERVE is undefined in FreeBSD 10.x and later.
+ * This is to enable 64bit HiPE experimentally on FreeBSD.
+ * Note that on FreeBSD MAP_NORESERVE was "never implemented"
+ * even before 11.x (and the flag does not exist in /usr/src/sys/vm/mmap.c
+ * of 10.3-STABLE r301478 either), and HiPE was working on OTP 18.3.3,
+ * so mandating MAP_NORESERVE on FreeBSD might not be needed.
+ * See the following message on how MAP_NORESERVE was treated on FreeBSD:
+ * <http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20150202/122958.html>
+ */
+#  if defined(MAP_FIXED) && (defined(MAP_NORESERVE) || defined(__FreeBSD__))
 #    define ERTS_HAVE_OS_PHYSICAL_MEMORY_RESERVATION 1
 #  endif
 #endif