Re: [PATCH 2/2] validate_subreg before call gen_lowpart to avoid ICE.

[Hongtao Liu via Gcc-patches]

On Sat, Sep 11, 2021 at 5:21 AM Segher Boessenkool
<seg...@kernel.crashing.org> wrote:
>
> On Fri, Sep 10, 2021 at 10:25:45PM +0800, Hongtao Liu wrote:
> > Updated patch.
> >
> >   Bootstrapped and regtested on x86_64-linux-gnu{-m32,},  do I need to
> > run this patch on other targets machine, or the patch is supposed to
> > have minimal impact on other targets?
> >   Then, ok for trunk?
>
> [-- Attachment #2: 
> v2-0001-Check-modes_tieable_p-before-call-gen_lowpart-to-.pat
> ch --]
> [-- Type: application/octet-stream, Encoding: base64, Size: 1.4K --]
>
> [-- application/octet-stream is unsupported (use 'v' to view this part) --]
>
> Please send your patches inline, or if you *have to* use attachments,
> use text attachments.  Without encoding.
>
hmm, my local file is
$file 0001-Check-modes_tieable_p-before-call-gen_lowpart-to-avo.patch
--mime-type
0001-Check-modes_tieable_p-before-call-gen_lowpart-to-avo.patch: text/x-diff

Didn't figure out how to let webgmail not change mime type of attachment.
> <https://gcc.gnu.org/contribute.html#patches>
>
> (It says "strongly discouraged", which means people will put it to the
> bottom of the stack of things to look at).
>
>
> Segher

Here is an updated patch.

  Bootstrapped and regtested on x86_64-linux-gnu{-m32,}
  Ok for trunk?

gcc/ChangeLog:

        * machmode.h (TRULY_NOOP_TRUNCATION_MODES_P): Check
        SCALAR_INT_MODE_P for both modes.
---
 gcc/machmode.h | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/gcc/machmode.h b/gcc/machmode.h
index 158351350de..9f95d7d046c 100644
--- a/gcc/machmode.h
+++ b/gcc/machmode.h
@@ -959,9 +959,10 @@ extern scalar_int_mode ptr_mode;
 /* Target-dependent machine mode initialization - in insn-modes.c.  */
 extern void init_adjust_machine_modes (void);

-#define TRULY_NOOP_TRUNCATION_MODES_P(MODE1, MODE2) \
-  (targetm.truly_noop_truncation (GET_MODE_PRECISION (MODE1), \
-                                 GET_MODE_PRECISION (MODE2)))
+#define TRULY_NOOP_TRUNCATION_MODES_P(MODE1, MODE2)                    \
+  (SCALAR_INT_MODE_P(MODE1) && SCALAR_INT_MODE_P(MODE2)                \
+   && targetm.truly_noop_truncation (GET_MODE_PRECISION (MODE1),       \
+                                    GET_MODE_PRECISION (MODE2)))

 /* Return true if MODE is a scalar integer mode that fits in a
    HOST_WIDE_INT.  */

-- 
BR,
Hongtao