Mark _d_allocmemory as ECF_PURE.

Author: ibuclaw

gcc/d/ChangeLog

@@ -1,3 +1,8 @@
+2018-02-11  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* d-codegen.cc (d_save_expr): Always stabilize CALL_EXPR.
+	* runtime.def (ALLOCMEMORY): Set ECF_PURE.
+
 2018-02-11  Iain Buclaw  <ibuclaw@gdcproject.org>
 
 	* runtime.def (ASSERT, ASSERT_MSG): Set ECF_COLD and ECF_LEAF flags.

gcc/d/d-codegen.cc

@@ -506,9 +506,14 @@ lvalue_p (tree exp)
 tree
 d_save_expr (tree exp)
 {
-  if (TREE_SIDE_EFFECTS (exp))
+  /* Always consider call expressions as a side effect, even if the function
+     being called is pure.  */
+  tree t = exp;
+  STRIP_NOPS (t);
+
+  if (TREE_SIDE_EFFECTS (t) || TREE_CODE (t) == CALL_EXPR)
     {
-      if (lvalue_p (exp))
+      if (lvalue_p (t))
 	return stabilize_reference (exp);
 
       return save_expr (exp);

gcc/d/runtime.def

@@ -118,7 +118,7 @@ DEF_D_RUNTIME (ARRAYSETLENGTHIT, "_d_arraysetlengthiT", RT(ARRAY_VOID),
 
 /* Used for allocating closures on the GC heap.  */
 DEF_D_RUNTIME (ALLOCMEMORY, "_d_allocmemory", RT(VOIDPTR), P1(SIZE_T),
-	       ECF_MALLOC)
+	       ECF_MALLOC | ECF_PURE)
 
 /* Used for copying an array into a slice, adds an enforcment that the source
    and destination are equal in size and do not overlap.  */