[Bug target/94494] New: gcc-10 unrecognizable insn

[abrahm.scully at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94494

            Bug ID: 94494
           Summary: gcc-10 unrecognizable insn
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: abrahm.scully at gmail dot com
  Target Milestone: ---

with gcc-10-20200329 built on 32-bit CentOS 6, passing -m32 -march=pentium3
-mfpmath=sse -mstackrealign -O2 -ftree-vectorize -flto ... got the following.

/build/file.cpp:1510:1: error: unrecognizable insn:
 1510 | }
      | ^
(insn 355 354 356 40 (set (reg:V1TI 201)
        (lshiftrt:V1TI (subreg:V1TI (reg:V4SI 89 [ vect_feature_found_41.571 ])
0)
            (const_int 64 [0x40]))) -1
     (nil))
during RTL pass: vregs
/build/file.cpp:1510:1: internal compiler error: in extract_insn, at
recog.c:2294
Please submit a full bug report,
with preprocessed source if appropriate.
See <https://gcc.gnu.org/bugs/> for instructions.

The same code built fine with gcc-9-20200118.