On Sun, Dec 01, 2019 at 08:09:56PM -0500, Marek Polacek wrote:
> On Thu, Nov 28, 2019 at 11:29:20PM -0500, Jason Merrill wrote:
> > Sounds like reduced_constant_expression_p needs to deal better with empty
> > bases.
>
> This got a bit complicated because it also needs to handle unions and
> now we also need to heed vptr. But the following seems to work.
>
> (I'll skip the story about a bogus error I hit when building cmcstl2 and
> the need to debug a ~90,000 LOC test, because creduce got stuck reducing
> it.)
Note, I got creduce stuck several times and what helped is:
--- /usr/bin/creduce 2019-02-15 17:17:32.000000000 +0100
+++ /usr/bin/creduce.nonnested 2019-11-30 11:34:21.604937392 +0100
@@ -802,7 +802,7 @@ my @all_methods = (
{ "name" => "pass_clang", "arg" => "local-to-global", "pri" =>
9500, "C" => 1, },
{ "name" => "pass_clang", "arg" => "param-to-global", "pri" =>
203, "C" => 1, },
{ "name" => "pass_clang", "arg" => "param-to-local", "pri" =>
204, "C" => 1, },
- { "name" => "pass_clang", "arg" => "remove-nested-function", "pri" =>
205, "C" => 1, },
+ #{ "name" => "pass_clang", "arg" => "remove-nested-function", "pri" =>
205, "C" => 1, },
{ "name" => "pass_clang", "arg" => "rename-fun",
"last_pass_pri" => 207, "C" => 1, },
{ "name" => "pass_clang", "arg" => "union-to-struct", "pri" =>
208, },
{ "name" => "pass_clang", "arg" => "rename-param",
"last_pass_pri" => 209, "C" => 1, },
where I can use creduce.nonnested if normal creduce gets stuck. That pass
tends to increase size of code rather than reduce if there are nested
functions, by adding a large series of temporaries:
type __reduce_tmp_123 = ...
type __reduce_tmp_122 = __reduce_tmp_123;
type __reduce_tmp_121 = __reduce_tmp_122;
type __reduce_tmp_120 = __reduce_tmp_121;
type __reduce_tmp_119 = __reduce_tmp_120;
type __reduce_tmp_118 = __reduce_tmp_119;
type __reduce_tmp_117 = __reduce_tmp_118;
...
and every iteration adds another line.
Jakub
