[PATCH 4/4] Initial version of RTL frontend

[Richard Biener]

On Tue, May 10, 2016 at 4:13 PM, David Malcolm <dmalcolm@redhat.com> wrote:
> On Wed, 2016-05-04 at 16:49 -0400, David Malcolm wrote:
> [...snip...]
>>
>> I wrote this by compiling a test.c with -fdump-rtl-all on
>> x86_64-pc-linux-gnu, and then attempting to load the state at each
>> pass, and then trying to run just one pass, and fixing bugs until the
>> dump output from each pass was the same as when running the pass from
>> cc1.  I've only done this with a small subset of passes, and with a
>> very
>> simple test case, so I'm sure there are plenty of bugs and "x86_64
>> -isms"
>> remaining.
>
> [...snip...]
>
> On the subject of "x86_64-isms", a couple of issues I ran into when
> testing with --target=aarch64-linux-gnu:
>
> * roundtrip.exp fails due to different register names so e.g. this from
> x86_64:
>
>      (reg:SI 5 di [ i ]))
>
>   becomes this after roundtripping on aarch64:
>
>      (reg:SI 5 x5 [ i ]))
>
>   (i.e. "di" vs "x5" for register 5).
>
> * unknown modes e.g. this from x86_64:
>
>     (reg:CCGC 17 flags)
>
>   fails on aarch64 due to the lack of a "CCGC" mode.

I expect most (if not all) RTL testcases will be target specific.

Richard.