[Bug tree-optimization/58805] [4.8/4.9 Regression] Inline assembly wrongly optimized out when inside a conditional

["vries at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58805

vries at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |vries at gcc dot gnu.org

--- Comment #11 from vries at gcc dot gnu.org ---
Using this tentative patch, tree-tail-merge leaves the test-case alone:
...
diff --git a/gcc/gimple.c b/gcc/gimple.c
index 3ddceb9..7e00037 100644
--- a/gcc/gimple.c
+++ b/gcc/gimple.c
@@ -2394,6 +2394,13 @@ gimple_copy (gimple stmt)
   return copy;
 }

+static bool
+return_true_bool_gimple_tree_voidptr (gimple s ATTRIBUTE_UNUSED,
+                                     tree t ATTRIBUTE_UNUSED,
+                                     void *p ATTRIBUTE_UNUSED)
+{
+  return true;
+}

 /* Return true if statement S has side-effects.  We consider a
    statement to have side effects if:
@@ -2413,9 +2420,16 @@ gimple_has_side_effects (const_gimple s)
   if (gimple_has_volatile_ops (s))
     return true;

-  if (gimple_code (s) == GIMPLE_ASM
-      && gimple_asm_volatile_p (s))
-    return true;
+  if (gimple_code (s) == GIMPLE_ASM)
+    {
+      if (gimple_asm_volatile_p (s))
+       return true;
+
+      if (walk_stmt_load_store_addr_ops ((gimple)s, NULL, NULL,
+                                        return_true_bool_gimple_tree_voidptr,
+                                        NULL))
+      return true;
+    }

   if (is_gimple_call (s))
     {
...