[PATCH 22/23] Add rtl-ssa

[Richard Sandiford]

Jeff Law via Gcc-patches <gcc-patches@gcc.gnu.org> writes:
> On 11/13/20 1:23 AM, Richard Sandiford via Gcc-patches wrote:
>> This patch adds the RTL SSA infrastructure itself.  The following
>> fwprop.c patch will make use of it.
>>
>> gcc/
>> 	* configure.ac: Add rtl-ssa to the list of dependence directories.
>> 	* configure: Regenerate.
>> 	* Makefile.in (rtl-ssa-warn): New variable.
>> 	(OBJS): Add the rtl-ssa object files.
>> 	* emit-rtl.h (rtl_data::ssa): New field.
>> 	* rtl-ssa.h: New file.
>> 	* system.h: Include <functional> when INCLUDE_FUNCTIONAL is defined.
>> 	* rtl-ssa: New directory.
> So I know its late in stage3, but I think the risks here are relatively
> minor as this would only be used in fwprop right now and it was posted
> in advance of the deadline.
>
> My high level questions/concerns have been addressed and while I
> strongly suspect we'll have to iterate on infrastructure, I think we can
> do that on demand as passes start to use the infrastructure and we have
> a clearer picture of what tweaks we need to make for the clients.

Agreed.  And I agree we'll need to iterate.  What's there now certainly
isn't complete.

> Obviously we'll want to keep an eye on testresults, but again, the
> potential for fallout here is relatively minor IMHO.  OK for the trunk.

Thanks a lot for the reviews.  Now pushed after retesting on
aarch64-linux-gnu (with and without SVE), arm-linux-gnueabihf
(as far as I could given the current state), x86_64-linux-gnu
and powerpc64le-linux-gnu.

Richard