[Bug rtl-optimization/78671] ICE: in extract_constrain_insn, at recog.c:2213 with -Og -march=skylake-avx512

[ubizjak at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78671

Uroš Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ra
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2016-12-04
                 CC|                            |vmakarov at gcc dot gnu.org
          Component|target                      |rtl-optimization
     Ever confirmed|0                           |1

--- Comment #1 from Uroš Bizjak <ubizjak at gmail dot com> ---
(In reply to Zdenek Sojka from comment #0)
> Created attachment 40241 [details]
> reduced testcase
> 
> Compiler output:
> $ x86_64-pc-linux-gnu-gcc -Og -march=skylake-avx512 testcase.c
> testcase.c: In function 'foo':
> testcase.c:15:1: error: insn does not satisfy its constraints:
>  }
>  ^
> (insn 554 165 166 14 (set (reg:TI 44 r15 [orig:149 _84 ] [149])
>         (reg:TI 40 r11 [orig:149 _84 ] [149])) "testcase.c":12 80
> {*movti_internal}
>      (nil))

64bit r15 was allocated as a TImode register, and there is no r16 to form
TImode register pair.