[Bug target/106609] [12/13 Regression] sh3eb-elf cross compiler is being miscompiled since r12-1525-g3155d51bfd1de8b6c4645

["jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106609

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2022-11-24
             Status|UNCONFIRMED                 |NEW
                 CC|                            |jakub at gcc dot gnu.org
     Ever confirmed|0                           |1

--- Comment #13 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Mikael Pettersson from comment #12)
> I tried compiling the gcc-13 cross compiler using the broken gcc-12 host
> compiler and -mtune-ctrl=^use_bt but that didn't help.
> 
> I then tried rebuilding the broken gcc-12 host compiler with the new
> splitters disabled, one by one. Disabling the "*bt<mode>_setcqi" one did
> unbreak the gcc-13 cross-compiler:
> 
> diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
> index 48532eb7ddf..0780ba992f3 100644
> --- a/gcc/config/i386/i386.md
> +++ b/gcc/config/i386/i386.md
> @@ -12830,7 +12830,7 @@
>           (const_int 1)
>           (zero_extend:SI (match_operand:QI 2 "register_operand"))))
>     (clobber (reg:CC FLAGS_REG))]
> -  "TARGET_USE_BT && ix86_pre_reload_split ()"
> +  "0 && TARGET_USE_BT && ix86_pre_reload_split ()"
>    "#"
>    "&& 1"
>    [(set (reg:CCC FLAGS_REG)

Ok, reproduced with last night's gcc trunk as the x86_64-linux system compiler
(with/without the above patch) and r12-8924-ga6b1f6126de5e4 as 12 branch for
the cross-compiler.  The difference appears first in the
sh_treg_combine2 dump
-not a condition store
-other set found - aborting trace
+inverted condition store
+tracing ccreg
+set of ccreg not found
+
+cbranch trace summary:
etc.
And bisection points to insn-preds.o.