[Hexagon] Preclude non-memory test from being optimized away. NFC.

llvm-svn: 307153
diff --git a/llvm/test/CodeGen/Hexagon/convertdptoint.ll b/llvm/test/CodeGen/Hexagon/convertdptoint.ll
index a09c2fd..adf76e5 100644
--- a/llvm/test/CodeGen/Hexagon/convertdptoint.ll
+++ b/llvm/test/CodeGen/Hexagon/convertdptoint.ll
@@ -12,10 +12,10 @@
   %b = alloca double, align 8
   %c = alloca double, align 8
   store i32 0, i32* %retval
-  store double 1.540000e+01, double* %a, align 8
-  store double 9.100000e+00, double* %b, align 8
-  %0 = load double, double* %a, align 8
-  %1 = load double, double* %b, align 8
+  store volatile double 1.540000e+01, double* %a, align 8
+  store volatile double 9.100000e+00, double* %b, align 8
+  %0 = load volatile double, double* %a, align 8
+  %1 = load volatile double, double* %b, align 8
   %add = fadd double %0, %1
   store double %add, double* %c, align 8
   %2 = load double, double* %c, align 8