[Bug rtl-optimization/88317] New: ICE: Segmentation fault (in split_reg -> bitmap_set_bit -> bitmap_list_link_element)

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88317

            Bug ID: 88317
           Summary: ICE: Segmentation fault (in split_reg ->
                    bitmap_set_bit -> bitmap_list_link_element)
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Keywords: ice-on-invalid-code, ra
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---
            Target: x86_64-unknown-linux-gnu

Created attachment 45143
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=45143&action=edit
The testcase

gcc-9.0.0-alpha20181202 snapshot (r266729) ICEs when compiling the attached
testcase w/ -O1 -fschedule-insns -fselective-scheduling -ftrapv
-funroll-all-loops -fno-tree-ccp -fno-tree-dce -fno-tree-dominator-opts
-fno-tree-fre -fno-tree-sra:

% x86_64-unknown-linux-gnu-gcc-9.0.0-alpha20181202 -O1 -fschedule-insns
-fselective-scheduling -ftrapv -funroll-all-loops -fno-tree-ccp -fno-tree-dce
-fno-tree-dominator-opts -fno-tree-fre -fno-tree-sra -w -c ovoyxfol.c -v
Using built-in specs.
COLLECT_GCC=x86_64-unknown-linux-gnu-gcc-9.0.0-alpha20181202
Target: x86_64-unknown-linux-gnu
Configured with:
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181202/work/gcc-9-20181202/configure
--host=x86_64-unknown-linux-gnu --build=x86_64-unknown-linux-gnu --prefix=/usr
--bindir=/usr/x86_64-unknown-linux-gnu/gcc-bin/9.0.0-alpha20181202
--includedir=/usr/lib/gcc/x86_64-unknown-linux-gnu/9.0.0-alpha20181202/include
--datadir=/usr/share/gcc-data/x86_64-unknown-linux-gnu/9.0.0-alpha20181202
--mandir=/usr/share/gcc-data/x86_64-unknown-linux-gnu/9.0.0-alpha20181202/man
--infodir=/usr/share/gcc-data/x86_64-unknown-linux-gnu/9.0.0-alpha20181202/info
--with-gxx-include-dir=/usr/lib/gcc/x86_64-unknown-linux-gnu/9.0.0-alpha20181202/include/g++-v9
--with-python-dir=/share/gcc-data/x86_64-unknown-linux-gnu/9.0.0-alpha20181202/python
--enable-languages=c,c++ --enable-obsolete --enable-secureplt --disable-werror
--with-system-zlib --disable-nls --enable-checking=yes --disable-esp
--enable-libstdcxx-time --disable-libstdcxx-pch --enable-shared
--enable-threads=posix --enable-__cxa_atexit --enable-clocale=gnu
--disable-multilib --with-multilib-list=m64 --disable-altivec
--disable-fixed-point --enable-targets=all --enable-libgomp
--disable-libmudflap --disable-libssp --disable-libmpx --disable-systemtap
--disable-vtable-verify --disable-libvtv --disable-libquadmath --enable-lto
--with-isl --disable-isl-version-check --disable-libsanitizer
--enable-default-pie --enable-default-ssp
Thread model: posix
gcc version 9.0.0-alpha20181202 20181202 (experimental) (GCC) 
COLLECT_GCC_OPTIONS='-O1' '-fschedule-insns' '-fselective-scheduling' '-ftrapv'
'-funroll-all-loops' '-fno-tree-ccp' '-fno-tree-dce' '-fno-tree-dominator-opts'
'-fno-tree-fre' '-fno-tree-sra' '-w' '-c' '-v' '-mtune=generic' '-march=x86-64'
 /usr/libexec/gcc/x86_64-unknown-linux-gnu/9.0.0-alpha20181202/cc1 -quiet -v
ovoyxfol.c -quiet -dumpbase ovoyxfol.c -mtune=generic -march=x86-64 -auxbase
ovoyxfol -O1 -w -version -fschedule-insns -fselective-scheduling -ftrapv
-funroll-all-loops -fno-tree-ccp -fno-tree-dce -fno-tree-dominator-opts
-fno-tree-fre -fno-tree-sra -o /tmp/ccZdGkhr.s
GNU C17 (GCC) version 9.0.0-alpha20181202 20181202 (experimental)
(x86_64-unknown-linux-gnu)
        compiled by GNU C version 9.0.0-alpha20181202 20181202 (experimental),
GMP version 6.1.2, MPFR version 4.0.1, MPC version 1.1.0, isl version
isl-0.20-GMP

GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
ignoring nonexistent directory "/usr/local/include"
ignoring nonexistent directory
"/usr/lib/gcc/x86_64-unknown-linux-gnu/9.0.0-alpha20181202/../../../../x86_64-unknown-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
 /usr/lib/gcc/x86_64-unknown-linux-gnu/9.0.0-alpha20181202/include
 /usr/lib/gcc/x86_64-unknown-linux-gnu/9.0.0-alpha20181202/include-fixed
 /usr/include
End of search list.
GNU C17 (GCC) version 9.0.0-alpha20181202 20181202 (experimental)
(x86_64-unknown-linux-gnu)
        compiled by GNU C version 9.0.0-alpha20181202 20181202 (experimental),
GMP version 6.1.2, MPFR version 4.0.1, MPC version 1.1.0, isl version
isl-0.20-GMP

GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
Compiler executable checksum: a92a885da50bf198a0c1fc913bab14ec
during RTL pass: reload
ovoyxfol.c: In function 'vb':
ovoyxfol.c:661:1: internal compiler error: Segmentation fault
  661 | }
      | ^
0xd0821f crash_signal
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181202/work/gcc-9-20181202/gcc/toplev.c:326
0x88ea20 bitmap_list_link_element
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181202/work/gcc-9-20181202/gcc/bitmap.c:212
0x88ea20 bitmap_set_bit(bitmap_head*, int)
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181202/work/gcc-9-20181202/gcc/bitmap.c:948
0xb8d824 split_reg
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181202/work/gcc-9-20181202/gcc/lra-constraints.c:5656
0xb9768f spill_hard_reg_in_range(int, reg_class, rtx_insn*, rtx_insn*)
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181202/work/gcc-9-20181202/gcc/lra-constraints.c:5764
0xb89c9f lra_split_hard_reg_for()
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181202/work/gcc-9-20181202/gcc/lra-assigns.c:1765
0xb84405 lra(_IO_FILE*)
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181202/work/gcc-9-20181202/gcc/lra.c:2533
0xb3b929 do_reload
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181202/work/gcc-9-20181202/gcc/ira.c:5469
0xb3b929 execute
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20181202/work/gcc-9-20181202/gcc/ira.c:5653

==17984== Invalid read of size 4
==17984==    at 0x88EA20: bitmap_list_link_element (bitmap.c:212)
==17984==    by 0x88EA20: bitmap_set_bit(bitmap_head*, int) (bitmap.c:948)
==17984==    by 0xB8D824: split_reg(bool, int, rtx_insn*, rtx_def*, rtx_insn*)
(lra-constraints.c:5656)
==17984==    by 0xB9768F: spill_hard_reg_in_range(int, reg_class, rtx_insn*,
rtx_insn*) (lra-constraints.c:5764)
==17984==    by 0xB89C9F: lra_split_hard_reg_for() (lra-assigns.c:1765)
==17984==    by 0xB84405: lra(_IO_FILE*) (lra.c:2533)
==17984==    by 0xB3B929: do_reload (ira.c:5469)
==17984==    by 0xB3B929: (anonymous
namespace)::pass_reload::execute(function*) (ira.c:5653)
==17984==    by 0xC27FC9: execute_one_pass(opt_pass*) (passes.c:2483)
==17984==    by 0xC286FF: execute_pass_list_1(opt_pass*) (passes.c:2569)
==17984==    by 0xC28711: execute_pass_list_1(opt_pass*) (passes.c:2570)
==17984==    by 0xC28738: execute_pass_list(function*, opt_pass*)
(passes.c:2580)
==17984==    by 0x90A2AF: cgraph_node::expand() (cgraphunit.c:2196)
==17984==    by 0x90B2A3: expand_all_functions (cgraphunit.c:2334)
==17984==    by 0x90B2A3: symbol_table::compile() [clone .part.0]
(cgraphunit.c:2685)
==17984==  Address 0x8000000010 is not stack'd, malloc'd or (recently) free'd

I've been chasing this group of failures down for about a year. The attached
testcase is unsuitable for the testsuite, yet it's the smallest one I could
come up with so far. The failure manifests itself in half dozen different ICEs
and RA hangs which can be encountered by making some random changes in the
testcase.