[Bug c++/61794] New: internal error: unrecognizable insn, from avx512 extract instruction

[agner at agner dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61794

            Bug ID: 61794
           Summary: internal error: unrecognizable insn, from avx512
                    extract instruction
           Product: gcc
           Version: 4.10.0
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: agner at agner dot org

Created attachment 33117
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=33117&action=edit
c++ file producing error

The attached file bug1.cpp generates internal error when compiling:
g++ -mavx512f bug1.cpp

g++ version: 4.9 and 4.10.0 20140706
binutils version: 2.24
Ubuntu version: 12.04.2 LTS


Error message:
==============
a@a-desktop:~/avx512$ g++ -mavx512f bug1.cpp
bug1.cpp: In member function ‘int32_t Vec16i::extract(uint32_t) const’:
bug1.cpp:59:5: error: unrecognizable insn:
     }
     ^
(insn 29 28 30 8 (set (reg:V4SI 89 [ D.12727 ])
        (vec_merge:V4SI (vec_select:V4SI (reg:V16SI 88 [ D.12726 ])
                (parallel [
                        (const_int 0 [0])
                        (const_int 1 [0x1])
                        (const_int 2 [0x2])
                        (const_int 3 [0x3])
                    ]))
            (reg:V4SI 86 [ D.12724 ])
            (reg:QI 113))) bug1.cpp:38 -1
     (nil))
bug1.cpp:59:5: internal compiler error: in extract_insn, at recog.c:2204
0xb25c68 _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
    ../.././gcc/rtl-error.c:109
0xb25c99 _fatal_insn_not_found(rtx_def const*, char const*, int, char const*)
    ../.././gcc/rtl-error.c:117
0xaf609e extract_insn(rtx_def*)
    ../.././gcc/recog.c:2204
0x980803 instantiate_virtual_regs_in_insn
    ../.././gcc/function.c:1561
0x980803 instantiate_virtual_regs
    ../.././gcc/function.c:1932
0x980803 execute
    ../.././gcc/function.c:1983
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