On Mon, 2018-01-08 at 12:25 -0500, Nathan Sidwell wrote: > On 01/08/2018 12:14 PM, Jakub Jelinek wrote: > > On Mon, Jan 08, 2018 at 12:10:50PM -0500, Nathan Sidwell wrote: > > > > Both "_S_terminal" VAR_DECLs have a "_CharT" > > > > TEMPLATE_TYPE_PARM, but > > > > these types are different tree nodes. > > > > > > correct. they are not EQ but are EQUAL (same_type_p will be > > > true). > > > > So perhaps location_wrapper_p could use that instead of pointer > > comparison. > > Though it would be expensive. > > If TYPE_STRUCTURAL_COMPARISON_P (or however it's spelt) is true, > it'll > be expensive. Otherwise it's a function call, a couple of > indirections > and a pointer compare. But still more expensive than ... > > > > Add a flag on the VIEW_CONVERT/NON_LVALUE expr explicitly noting > > > its > > > wrapperness (rather than infer it from TREE_TYPE == TREE_TYPE > > > (TREE_OPERAND)). TREE_LANG_FLAG_0 looks available? > > > > Yeah, I think most if not all lang flags are still available for > > those two > > tree codes and checking that should be quite cheap. > > ... a bit test on the node itself. > > location_wrapper_p could contain something like > bool result = TREE_LANG_FLAG_$FOO (t); > gcc_checking_assert (result == same_type_p (TREE_TYPE (t), > TREE_TYPE > (TREE_OPERAND (t, 0))); > return result; > > for the paranoid. > > nathan
Thanks Nathan and Jakub: a quick smoketest using TREE_LANG_FLAG_0 worked, and fixes this issue. However, should I be using a TREE_LANG_FLAG for something that's in tree.h/c, rather than just in the "cp" subdir? (the wrapper nodes are only added to C++ in this patch kit, but given that e.g. STRIP_NOPS needs to remove them, the lang-independent code needs to handle them, and ultimately we may want wrapper nodes in other FEs). Dave
