[llvm-commits] [llvm] r90683 - /llvm/trunk/cmake/modules/CheckAtomic.cmake

[Oscar Fuentes]

Author: ofv
Date: Sat Dec  5 17:19:33 2009
New Revision: 90683

URL: http://llvm.org/viewvc/llvm-project?rev=90683&view=rev
Log:
Fix for atomic intrinsics detection when using MSVC.

Patch by Michael Beck!

Modified:
    llvm/trunk/cmake/modules/CheckAtomic.cmake

Modified: llvm/trunk/cmake/modules/CheckAtomic.cmake
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/cmake/modules/CheckAtomic.cmake?rev=90683&r1=90682&r2=90683&view=diff

==============================================================================
--- llvm/trunk/cmake/modules/CheckAtomic.cmake (original)
+++ llvm/trunk/cmake/modules/CheckAtomic.cmake Sat Dec  5 17:19:33 2009
@@ -1,14 +1,26 @@
 # atomic builtins are required for threading support.
 
 INCLUDE(CheckCXXSourceCompiles)
+
+#ifdef _MSC_VER
+#include <windows.h>
+#endif
 	
 CHECK_CXX_SOURCE_COMPILES("
 int main() {
+#ifdef _MSC_VER
+        volatile LONG val = 1;
+        MemoryBarrier();
+        InterlockedCompareExchange(&val, 0, 1);
+        InterlockedIncrement(&val);
+        InterlockedDecrement(&val);
+#else
         volatile unsigned long val = 1;
         __sync_synchronize();
         __sync_val_compare_and_swap(&val, 1, 0);
         __sync_add_and_fetch(&val, 1);
         __sync_sub_and_fetch(&val, 1);
+#endif
         return 0;
       }
 " LLVM_MULTITHREADED)