Simplify '#if' expressions in gcc/x86.h

(code refactoring)

* src/atomic_ops/sysdeps/gcc/x86.h [AO_GCC_ATOMIC_TEST_AND_SET]
(AO_SKIPATOMIC_double_compare_and_swap_ANY, AO_SKIPATOMIC_double_load,
AO_SKIPATOMIC_double_load_acquire, AO_SKIPATOMIC_double_store,
AO_SKIPATOMIC_double_store_release): Simplify "#if" condition
expressions.

1 files changed, 47 insertions, 39 deletions

diff --git a/src/atomic_ops/sysdeps/gcc/x86.h b/src/atomic_ops/sysdeps/gcc/x86.h
index f1e927f..7a7c689 100644
--- a/src/atomic_ops/sysdeps/gcc/x86.h
+++ b/src/atomic_ops/sysdeps/gcc/x86.h
@@ -21,50 +21,58 @@
     && !defined(AO_DISABLE_GCC_ATOMICS)
 # define AO_GCC_ATOMIC_TEST_AND_SET
 
-/* TODO: Refine for newer clang releases. */
-# if defined(__clang__) \
-     && (!(defined(__x86_64__) || defined(__APPLE_CC__) \
-           || defined(__CYGWIN__) || defined(AO_PREFER_BUILTIN_ATOMICS)) \
-         || (defined(__x86_64__) && !defined(__ILP32__) \
-             && (!(AO_CLANG_PREREQ(3, 5) \
-                   || defined(AO_PREFER_BUILTIN_ATOMICS)) \
-                 || defined(AO_ADDRESS_SANITIZER) \
-                 || defined(AO_THREAD_SANITIZER))))
-    /* As of clang-3.8 i686 (NDK r11c), it requires -latomic for all    */
-    /* the double-wide operations.  Same for clang-3.4/x64.  For now,   */
-    /* we fall back to the non-intrinsic implementation by default.     */
-    /* As of clang-4.0, double-wide arguments are incorrectly passed to */
-    /* atomic intrinsic operations for x64 target if ASan/TSan enabled. */
-#   define AO_SKIPATOMIC_double_compare_and_swap_ANY
-#   define AO_SKIPATOMIC_double_load
-#   define AO_SKIPATOMIC_double_load_acquire
-#   define AO_SKIPATOMIC_double_store
-#   define AO_SKIPATOMIC_double_store_release
-# elif defined(__APPLE_CC__) && defined(__x86_64__)
-    /* As of Apple clang-600 (based on LLVM 3.5svn), it has some bug in */
-    /* double-wide CAS implementation for x64 target.                   */
-#   define AO_SKIPATOMIC_double_compare_and_swap_ANY
-# endif
-
 # if defined(__APPLE_CC__)
     /* OS X 10.7 clang-425 lacks __GCC_HAVE_SYNC_COMPARE_AND_SWAP_n     */
     /* predefined macro (unlike e.g. OS X 10.11 clang-703).             */
 #   define AO_GCC_FORCE_HAVE_CAS
-# endif
 
-# if !defined(__x86_64__) && defined(__APPLE__) && defined(__MACH__)
-    /* OS X 10.8 lacks __atomic_load/store symbols for arch i386 (even  */
-    /* with non-Apple clang).                                           */
-#   ifndef MAC_OS_X_VERSION_MIN_REQUIRED
-      /* Include this header just to import the version macro.  */
-#     include <AvailabilityMacros.h>
-#   endif
-#   if MAC_OS_X_VERSION_MIN_REQUIRED < 1090 /* MAC_OS_X_VERSION_10_9 */
-#     define AO_SKIPATOMIC_double_load
-#     define AO_SKIPATOMIC_double_load_acquire
-#     define AO_SKIPATOMIC_double_store
-#     define AO_SKIPATOMIC_double_store_release
-#   endif
+#   ifdef __x86_64__
+      /* As of Apple clang-600 (based on LLVM 3.5svn), it has some bug  */
+      /* in the double-wide CAS implementation for x64 target.          */
+      /* TODO: Refine for newer Apple clang releases. */
+#       define AO_SKIPATOMIC_double_compare_and_swap_ANY
+
+#   elif defined(__MACH__)
+      /* OS X 10.8 lacks __atomic_load/store symbols for arch i386      */
+      /* (even with a non-Apple clang).                                 */
+#     ifndef MAC_OS_X_VERSION_MIN_REQUIRED
+        /* Include this header just to import the version macro. */
+#       include <AvailabilityMacros.h>
+#     endif
+#     if MAC_OS_X_VERSION_MIN_REQUIRED < 1090 /* MAC_OS_X_VERSION_10_9  */
+#       define AO_SKIPATOMIC_DOUBLE_LOAD_STORE_ANY
+#     endif
+#   endif /* __i386__ */
+
+# elif defined(__clang__)
+#   if !defined(__x86_64__)
+#     if !defined(AO_PREFER_BUILTIN_ATOMICS) && !defined(__CYGWIN__)
+        /* As of clang-3.8/i686 (NDK r11c), it requires -latomic for    */
+        /* all the double-wide operations.  For now, we fall back to    */
+        /* the non-intrinsic implementation by default.                 */
+        /* TODO: Refine for newer clang releases. */
+#       define AO_SKIPATOMIC_double_compare_and_swap_ANY
+#       define AO_SKIPATOMIC_DOUBLE_LOAD_STORE_ANY
+#     endif /* !AO_PREFER_BUILTIN_ATOMICS */
+
+#   elif !defined(__ILP32__)
+#     if (!AO_CLANG_PREREQ(3, 5) && !defined(AO_PREFER_BUILTIN_ATOMICS)) \
+         || defined(AO_ADDRESS_SANITIZER) || defined(AO_THREAD_SANITIZER)
+        /* Same as above but for clang-3.4/x64.  As of clang-4.0,       */
+        /* double-wide arguments are incorrectly passed to atomic       */
+        /* intrinsic operations for x64 target if ASan/TSan enabled.    */
+#       define AO_SKIPATOMIC_double_compare_and_swap_ANY
+#       define AO_SKIPATOMIC_DOUBLE_LOAD_STORE_ANY
+#     endif
+#   endif /* __x86_64__ */
+# endif /* __clang__ */
+
+# ifdef AO_SKIPATOMIC_DOUBLE_LOAD_STORE_ANY
+#   define AO_SKIPATOMIC_double_load
+#   define AO_SKIPATOMIC_double_load_acquire
+#   define AO_SKIPATOMIC_double_store
+#   define AO_SKIPATOMIC_double_store_release
+#   undef AO_SKIPATOMIC_DOUBLE_LOAD_STORE_ANY
 # endif
 
 #else /* AO_DISABLE_GCC_ATOMICS */