d: Always set ASM_VOLATILE_P on asm statements (PR94425)

gcc/d/ChangeLog:

	PR d/94425
	* toir.cc (IRVisitor::visit (GccAsmStatement *)): Set ASM_VOLATILE_P
	on all asm statements.

gcc/d/ChangeLog

+2020-04-07  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	PR d/94425
+	* toir.cc (IRVisitor::visit (GccAsmStatement *)): Set ASM_VOLATILE_P
+	on all asm statements.
+
 2020-04-01  Iain Buclaw  <ibuclaw@gdcproject.org>
 
 	PR d/90136

gcc/d/toir.cc

@@ -1427,8 +1427,9 @@ public:
     if (s->args == NULL && s->clobbers == NULL)
       ASM_INPUT_P (exp) = 1;
 
-    /* Asm statements are treated as volatile unless 'pure'.  */
-    ASM_VOLATILE_P (exp) = !(s->stc & STCpure);
+    /* All asm statements are assumed to have a side effect.  As a future
+       optimization, this could be unset when building in release mode.  */
+    ASM_VOLATILE_P (exp) = 1;
 
     add_stmt (exp);
   }