[Bug c/59942] New: pdp11-aout-gcc: PDP-11/10 code generation crashes when trying to do multiple shifts.

[mattis at mattisborgen dot se]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59942

            Bug ID: 59942
           Summary: pdp11-aout-gcc: PDP-11/10 code generation crashes when
                    trying to do multiple shifts.
           Product: gcc
           Version: 4.8.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: mattis at mattisborgen dot se

This bug only occurs for PDP-11/10 not PDP-11/40. I presume that when using
PDP-11/40 the code generation will output a ASHC instruction which is not
present in the PDP-11/10.


mattis@mattis-VirtualBox:~$ pdp11-aout-gcc -m10  -S -msoft-float  -nostartfiles
 -nodefaultlibs  -nostdlib   pdp11-10-shiftbug.c 
pdp11-10-shiftbug.c: In function 'main':
pdp11-10-shiftbug.c:5:1: error: unrecognizable insn:
 }
 ^
(insn 8 7 9 2 (set (reg:HI 23)
        (ashift:HI (reg:HI 24)
            (const_int -9 [0xfffffff7]))) pdp11-10-shiftbug.c:4 -1
     (nil))
pdp11-10-shiftbug.c:5:1: internal compiler error: in extract_insn, at
recog.c:2154
0x837d527 _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
    ../src/gcc/rtl-error.c:109
0x837d571 _fatal_insn_not_found(rtx_def const*, char const*, int, char const*)
    ../src/gcc/rtl-error.c:117
0x8355394 extract_insn(rtx_def*)
    ../src/gcc/recog.c:2154
0x825d34e instantiate_virtual_regs_in_insn
    ../src/gcc/function.c:1561
0x825d34e instantiate_virtual_regs
    ../src/gcc/function.c:1928
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
mattis@mattis-VirtualBox:~$ cat pdp11-10-shiftbug.c
main ()
{
  short a=10000, b;
  b = a >> 9;
}
mattis@mattis-VirtualBox:~$ pdp11-aout-gcc -v
Using built-in specs.
COLLECT_GCC=pdp11-aout-gcc
COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/pdp11-aout/4.8.2/lto-wrapper
Target: pdp11-aout
Configured with: src/configure --target=pdp11-aout --disable-nls
--without-headers --enable-languages=c
Thread model: single
gcc version 4.8.2 (GCC) 
mattis@mattis-VirtualBox:~$ 

Linux mattis-VirtualBox 3.8.0-35-generic #50~precise1-Ubuntu SMP Wed Dec 4
17:28:45 UTC 2013 i686 i686 i386 GNU/Linux