This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: New jump threading issue
- From: Segher Boessenkool <segher at kernel dot crashing dot org>
- To: Andrew Stubbs <ams at codesourcery dot com>
- Cc: GCC Development <gcc at gcc dot gnu dot org>
- Date: Fri, 7 Dec 2018 16:41:42 -0600
- Subject: Re: New jump threading issue
- References: <7beea154-f4ef-21e3-d68a-1c9d04b7f01c@codesourcery.com>
On Fri, Dec 07, 2018 at 05:57:39PM +0000, Andrew Stubbs wrote:
> Since the postreload_jump pass was added I'm having trouble with the AMD
> GCN port.
[ snip a lot ]
It seems thread_jump does not notice your scc in its "nonequal" regset,
so it thinks every later jump is based on the same scc setting as the
first, which explains this behaviour. Is this true, and if so, what
causes it?
Segher