[Bug target/84786] [miscompilation] vunpcklpd accessing xmm16-22 targeting KNL

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84786

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2018-03-12
           Assignee|unassigned at gcc dot gnu.org      |jakub at gcc dot gnu.org
     Ever confirmed|0                           |1

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Ah, I see the bug:
(define_insn "sse2_loadhpd"
  [(set (match_operand:V2DF 0 "nonimmediate_operand"
          "=x,v,x,v,o,o ,o")
        (vec_concat:V2DF
          (vec_select:DF
            (match_operand:V2DF 1 "nonimmediate_operand"
          " 0,v,0,v,0,0 ,0")
            (parallel [(const_int 0)]))
          (match_operand:DF 2 "nonimmediate_operand"
          " m,m,x,v,x,*f,r")))]
While V2DFmode won't be put into %xmm16-%xmm31 without TARGET_AVX512VL, DFmode
can be, so we need an avx512vl alternative for the v for the last operand and
another one with x for avx/avx2/avx512f etc. without avx512vl.