Use DoNotOptimize to prevent new/delete elision.

The new/delete tests, in particular those which test replacement
functions, often fail when the optimizer is enabled because the
calls to new/delete may be optimized away, regardless of their side-effects.

This patch converts the tests to use DoNotOptimize in order to prevent
the elision.

llvm-svn: 328245

1 files changed, 12 insertions, 2 deletions

diff --git a/libcxx/test/support/test_macros.h b/libcxx/test/support/test_macros.h
index 42eed4ce498..848f1407635 100644
--- a/libcxx/test/support/test_macros.h
+++ b/libcxx/test/support/test_macros.h
@@ -221,8 +221,18 @@ struct is_same<T, T> { enum {value = 1}; };
 
 #if defined(__GNUC__) || defined(__clang__)
 template <class Tp>
-inline void DoNotOptimize(Tp const& value) {
-  asm volatile("" : : "g"(value) : "memory");
+inline
+void DoNotOptimize(Tp const& value) {
+    asm volatile("" : : "r,m"(value) : "memory");
+}
+
+template <class Tp>
+inline void DoNotOptimize(Tp& value) {
+#if defined(__clang__)
+  asm volatile("" : "+r,m"(value) : : "memory");
+#else
+  asm volatile("" : "+m,r"(value) : : "memory");
+#endif
 }
 #else
 #include <intrin.h>