[Bug target/58901] New: vax bootstrap fails on subreg reload

[martin at netbsd dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58901

            Bug ID: 58901
           Summary: vax bootstrap fails on subreg reload
           Product: gcc
           Version: 4.8.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: martin at netbsd dot org

Trying a native bootstrap on VAX fails when compiling libdecnumber with a
failed assertion here:

#0  0x0085637c in fancy_abort (file=0x8dae4d "../../gcc-4.8.2/gcc/emit-rtl.c", 
    line=2019, 
    function=0x8db1e3 <change_address_1(rtx_def*, machine_mode, rtx_def*,
int)::__FUNCTION__> "change_address_1", 9285197, 2019, 9286115)
    at ../../gcc-4.8.2/gcc/diagnostic.c:1146
#1  0x00295470 in change_address_1 (memref=0x7ea2d560, mode=HImode, 
    addr=0x7ea0fd2c, validate=1, 2124600672, 5, 2124479788, 1)
    at ../../gcc-4.8.2/gcc/emit-rtl.c:2019
#2  0x00295f54 in adjust_address_1 (memref=0x7ea2d560, mode=HImode, offset=0, 
    validate=1, adjust_address=1, adjust_object=0, 
    size=2, 2124600672, 5, 0, 1, 1, 0, 2)
    at ../../gcc-4.8.2/gcc/emit-rtl.c:2151
#3  0x002d1a06 in alter_subreg (xp=0x7f0e8bc8, final_p=true, 2131659720, 1)
    at ../../gcc-4.8.2/gcc/final.c:3072
#4  0x002d2231 in cleanup_subreg_operands (insn=0x7f2d6360, 2133680992)
    at ../../gcc-4.8.2/gcc/final.c:3018
#5  0x004e5810 in reload (first=0x7ea58620, global=1, 2124776992, 1)
    at ../../gcc-4.8.2/gcc/reload1.c:1240
#6  0x003dc5e2 in do_reload () at ../../gcc-4.8.2/gcc/ira.c:4679
#7  0x003dc7aa in rest_of_handle_reload () at ../../gcc-4.8.2/gcc/ira.c:4779
#8  0x00483bf5 in execute_one_pass (pass=0xc6fda4 <pass_reload>, 13041060)
    at ../../gcc-4.8.2/gcc/passes.c:2333

(gdb) p debug_rtx(memref)
(mem/u/c:SI (plus:SI (mult:SI (reg/v:SI 0 %r0 [orig:81 count ] [81])
            (const_int 4 [0x4]))
        (symbol_ref:SI ("DECPOWERS") [flags 0x40] <var_decl 0x7f22fe60
DECPOWERS>)) [3 DECPOWERS S4 A32])

The invocation was:

/usr/pkgobj/lang/gcc48/work/build/./prev-gcc/cc1 -quiet -v -I
../../gcc-4.8.2/libdecnumber -I . -I /usr/pkg/include -I /usr/include -I
../../gcc-4.8.2/libdecnumber -I . -I /usr/pkg/include -I /usr/include -iprefix
/usr/pkgobj/lang/gcc48/work/build/prev-gcc/../lib/gcc/vax--netbsdelf/4.8.2/
-isystem /usr/pkgobj/lang/gcc48/work/build/./prev-gcc/include -isystem
/usr/pkgobj/lang/gcc48/work/build/./prev-gcc/include-fixed -isystem
/usr/pkg/gcc48/vax--netbsdelf/include -isystem
/usr/pkg/gcc48/vax--netbsdelf/sys-include
../../gcc-4.8.2/libdecnumber/decNumber.c -fPIC -quiet -dumpbase decNumber.c
-auxbase decNumber -g -gtoggle -O2 -Wextra -Wall -Wwrite-strings
-Wstrict-prototypes -Wmissing-prototypes -Wold-style-definition
-Wsuggest-attribute=format -Wcast-qual -Wpedantic -Wno-long-long -version -o
/var/tmp//ccfituj1.s