[Bug target/104409] New: [Aarch64] Crash when compiling source code of any significant size with -march=armv8.7-a

[Bug target/104409] New: [Aarch64] Crash when compiling source code of any significant size with -march=armv8.7-a

[gabravier at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104409

            Bug ID: 104409
           Summary: [Aarch64] Crash when compiling source code of any
                    significant size with -march=armv8.7-a
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gabravier at gmail dot com
  Target Milestone: ---

Created attachment 52361
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=52361&action=edit
Preprocessed minimal code that triggers the crash

It appears that using `-march=armv8.7-a` on code of any significant size
quickly results in a crash. Compiling the attached code with that option
results in a crash on Godbolt's trunk build (updated as of sometime today) of
Aarch64 GCC (here's a Godbolt link if you want to see it reproduced there, btw:
https://godbolt.org/z/GWh1r6MWj)

The complete command line is this: `aarch64-linux-gnu-g++ -g -o
/tmp/compiler-explorer-compiler202216-6419-6qrckn.k4c16/output.s -S
-fdiagnostics-color=always -march=armv8.7-a -v
/tmp/compiler-explorer-compiler202216-6419-6qrckn.k4c16/example.cpp`

The compiler output is this:

<source>:2280:5: internal compiler error: Segmentation fault
 2280 |     }
      |     ^
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
See <https://gcc.gnu.org/bugs/> for instructions.

The information from gcc -v is this:

Using built-in specs.
COLLECT_GCC=/opt/compiler-explorer/arm64/gcc-trunk/aarch64-unknown-linux-gnu/bin/aarch64-unknown-linux-gnu-g++
Target: aarch64-unknown-linux-gnu
Configured with: /opt/.build/aarch64-unknown-linux-gnu/src/gcc/configure
--build=x86_64-build_pc-linux-gnu --host=x86_64-build_pc-linux-gnu
--target=aarch64-unknown-linux-gnu
--prefix=/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu
--exec_prefix=/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu
--with-sysroot=/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu/aarch64-unknown-linux-gnu/sysroot
--enable-languages=c,c++,fortran --enable-__cxa_atexit --disable-libmudflap
--enable-libgomp --enable-libssp --enable-libquadmath
--enable-libquadmath-support --enable-libsanitizer --disable-libmpx
--with-gmp=/opt/.build/aarch64-unknown-linux-gnu/buildtools
--with-mpfr=/opt/.build/aarch64-unknown-linux-gnu/buildtools
--with-mpc=/opt/.build/aarch64-unknown-linux-gnu/buildtools
--with-isl=/opt/.build/aarch64-unknown-linux-gnu/buildtools --disable-lto
--without-zstd --enable-threads=posix --enable-target-optspace --disable-plugin
--disable-nls --disable-multilib
--with-local-prefix=/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu/aarch64-unknown-linux-gnu/sysroot
--enable-long-long
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 12.0.1 20220206 (experimental) (GCC) 
COLLECT_GCC_OPTIONS='-fdiagnostics-color=always' '-g' '-o' '/app/output.s' '-S'
'-march=armv8.7-a' '-v' '-shared-libgcc' '-mlittle-endian' '-mabi=lp64'
'-dumpdir' '/app/'

/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu/libexec/gcc/aarch64-unknown-linux-gnu/12.0.1/cc1plus
-quiet -v -D_GNU_SOURCE <source> -quiet -dumpdir /app/ -dumpbase output.cpp
-dumpbase-ext .cpp -march=armv8.7-a -mlittle-endian -mabi=lp64 -g -version
-fdiagnostics-color=always -o /app/output.s
GNU C++17 (GCC) version 12.0.1 20220206 (experimental)
(aarch64-unknown-linux-gnu)
        compiled by GNU C version 7.5.0, GMP version 6.1.2, MPFR version 4.0.2,
MPC version 1.1.0, isl version isl-0.19-GMP

GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
ignoring nonexistent directory
"/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu/aarch64-unknown-linux-gnu/sysroot/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu/aarch64-unknown-linux-gnu/sysroot/include"
#include "..." search starts here:
#include <...> search starts here:

/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu/lib/gcc/aarch64-unknown-linux-gnu/12.0.1/../../../../aarch64-unknown-linux-gnu/include/c++/12.0.1

/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu/lib/gcc/aarch64-unknown-linux-gnu/12.0.1/../../../../aarch64-unknown-linux-gnu/include/c++/12.0.1/aarch64-unknown-linux-gnu

/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu/lib/gcc/aarch64-unknown-linux-gnu/12.0.1/../../../../aarch64-unknown-linux-gnu/include/c++/12.0.1/backward

/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu/lib/gcc/aarch64-unknown-linux-gnu/12.0.1/include

/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu/lib/gcc/aarch64-unknown-linux-gnu/12.0.1/include-fixed

/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu/lib/gcc/aarch64-unknown-linux-gnu/12.0.1/../../../../aarch64-unknown-linux-gnu/include

/opt/compiler-explorer/arm64/gcc-trunk-20220206/aarch64-unknown-linux-gnu/aarch64-unknown-linux-gnu/sysroot/usr/include
End of search list.
GNU C++17 (GCC) version 12.0.1 20220206 (experimental)
(aarch64-unknown-linux-gnu)
        compiled by GNU C version 7.5.0, GMP version 6.1.2, MPFR version 4.0.2,
MPC version 1.1.0, isl version isl-0.19-GMP

GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
Compiler executable checksum: b30bfe5a5b063f6ba9d394e1fcceb1ed

[Bug target/104409] [Aarch64] Crash when compiling source code of any significant size with -march=armv8.7-a

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104409

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|GC                          |

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Here is some stuff from valgrind:
==2620791== Invalid write of size 8
==2620791==    at 0x74A1EC: pushclass(tree_node*) (in
/bajas/pinskia/src/upstream-gcc-aarch64/gcc/objdir/gcc/cc1plus)
==2620791==    by 0x9F87B7: begin_class_definition(tree_node*) (in
/bajas/pinskia/src/upstream-gcc-aarch64/gcc/objdir/gcc/cc1plus)
==2620791==    by 0x809183: cxx_simulate_record_decl(unsigned int, char const*,
array_slice<tree_node* const>) (in
/bajas/pinskia/src/upstream-gcc-aarch64/gcc/objdir/gcc/cc1plus)
==2620791==    by 0x1500B23: aarch64_general_init_builtins() (in
/bajas/pinskia/src/upstream-gcc-aarch64/gcc/objdir/gcc/cc1plus)
==2620791==    by 0x144CACB: aarch64_init_builtins() (in
/bajas/pinskia/src/upstream-gcc-aarch64/gcc/objdir/gcc/cc1plus)
==2620791==    by 0xA9E303: c_define_builtins(tree_node*, tree_node*) (in
/bajas/pinskia/src/upstream-gcc-aarch64/gcc/objdir/gcc/cc1plus)
==2620791==    by 0xAA7DC3: c_common_nodes_and_builtins() (in
/bajas/pinskia/src/upstream-gcc-aarch64/gcc/objdir/gcc/cc1plus)
==2620791==    by 0x8069CF: cxx_init_decl_processing() (in
/bajas/pinskia/src/upstream-gcc-aarch64/gcc/objdir/gcc/cc1plus)
==2620791==    by 0x869157: cxx_init() (in
/bajas/pinskia/src/upstream-gcc-aarch64/gcc/objdir/gcc/cc1plus)
==2620791==    by 0x70FDE3: toplev::main(int, char**) (in
/bajas/pinskia/src/upstream-gcc-aarch64/gcc/objdir/gcc/cc1plus)
==2620791==    by 0x711203: main (in
/bajas/pinskia/src/upstream-gcc-aarch64/gcc/objdir/gcc/cc1plus)
==2620791==  Address 0x4d6ffe0 is 0 bytes inside a block of size 1 alloc'd
==2620791==    at 0x4853BFC: malloc (in
/usr/lib/valgrind/vgpreload_memcheck-arm64-linux.so)

[Bug target/104409] -march=armv8.6-a+ls64 crashes, LS64 builtins causes ICE

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104409

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2022-02-06

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I can also reproduce the ICE with -march=armv8.6-a+ls64 .

[Bug target/104409] -march=armv8.6-a+ls64 crashes, LS64 builtins causes ICE

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104409

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |zsojka at seznam dot cz

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
*** Bug 104473 has been marked as a duplicate of this bug. ***

[Bug target/104409] -march=armv8.6-a+ls64 crashes, LS64 builtins causes ICE

[zsojka at seznam dot cz]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104409

--- Comment #4 from Zdenek Sojka <zsojka at seznam dot cz> ---
Probably related crash: (with -fpack-struct)
$ echo > testcase.c
aarch64-unknown-linux-gnu-gcc -march=armv8.6-a+ls64 -fpack-struct testcase.c 
<built-in>: internal compiler error: in aarch64_init_ls64_builtins_types, at
config/aarch64/aarch64-builtins.cc:1616
0x8645dc aarch64_init_ls64_builtins_types
        /repo/gcc-trunk/gcc/config/aarch64/aarch64-builtins.cc:1616
0x8645dc aarch64_init_ls64_builtins
        /repo/gcc-trunk/gcc/config/aarch64/aarch64-builtins.cc:1622
0x8645dc aarch64_general_init_builtins()
        /repo/gcc-trunk/gcc/config/aarch64/aarch64-builtins.cc:1735
0x14b06b8 aarch64_init_builtins
        /repo/gcc-trunk/gcc/config/aarch64/aarch64.cc:14335
0xb6d2bd c_define_builtins
        /repo/gcc-trunk/gcc/c-family/c-common.cc:4221
0xb6d2bd c_common_nodes_and_builtins()
        /repo/gcc-trunk/gcc/c-family/c-common.cc:4708
0xac0678 c_init_decl_processing()
        /repo/gcc-trunk/gcc/c/c-decl.cc:4503
0xb07368 c_objc_common_init()
        /repo/gcc-trunk/gcc/c/c-objc-common.cc:62
0xaac283 lang_dependent_init
        /repo/gcc-trunk/gcc/toplev.cc:1848
0xaac283 do_compile
        /repo/gcc-trunk/gcc/toplev.cc:2143
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

[Bug target/104409] -march=armv8.6-a+ls64 crashes, LS64 builtins causes ICE

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104409

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Zdenek Sojka from comment #4)
> Probably related crash: (with -fpack-struct)
That is recorded as PR 103147 already.

[Bug target/104409] -march=armv8.6-a+ls64 crashes, LS64 builtins causes ICE

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104409

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |marxin at gcc dot gnu.org,
                   |                            |wirkus at gcc dot gnu.org

--- Comment #6 from Martin Liška <marxin at gcc dot gnu.org> ---
So the root cause is quite simple:

#0  pushclass (type=<record_type 0x7ffff749bdc8 __arm_data512_t>) at
/home/marxin/Programming/gcc/gcc/cp/class.cc:8069
#1  0x0000000000f869ea in begin_class_definition (t=<record_type 0x7ffff749bdc8
__arm_data512_t>) at /home/marxin/Programming/gcc/gcc/cp/semantics.cc:3466
#2  0x0000000000d284da in cxx_simulate_record_decl (loc=1, name=0x2edeca1
"__arm_data512_t", fields=...) at
/home/marxin/Programming/gcc/gcc/cp/decl.cc:16689
#3  0x0000000001e51927 in aarch64_init_ls64_builtins_types () at
/home/marxin/Programming/gcc/gcc/config/aarch64/aarch64-builtins.cc:1610
#4  0x0000000001e51ac4 in aarch64_init_ls64_builtins () at
/home/marxin/Programming/gcc/gcc/config/aarch64/aarch64-builtins.cc:1622
#5  0x0000000001e51f17 in aarch64_general_init_builtins () at
/home/marxin/Programming/gcc/gcc/config/aarch64/aarch64-builtins.cc:1735
#6  0x0000000001d57551 in aarch64_init_builtins () at
/home/marxin/Programming/gcc/gcc/config/aarch64/aarch64.cc:14489
#7  0x000000000105c566 in c_define_builtins
(va_list_ref_type_node=<reference_type 0x7ffff76347e0>,
va_list_arg_type_node=<record_type 0x7ffff76329d8 __va_list>) at
/home/marxin/Programming/gcc/gcc/c-family/c-common.cc:4225
#8  0x000000000105e204 in c_common_nodes_and_builtins () at
/home/marxin/Programming/gcc/gcc/c-family/c-common.cc:4712
#9  0x0000000000cf6279 in cxx_init_decl_processing () at
/home/marxin/Programming/gcc/gcc/cp/decl.cc:4452
#10 0x0000000000d9bb5e in cxx_init () at
/home/marxin/Programming/gcc/gcc/cp/lex.cc:328
#11 0x000000000186796c in lang_dependent_init (name=0x3982f00
"/home/marxin/Programming/testcases/pr104409.c") at
/home/marxin/Programming/gcc/gcc/toplev.cc:1858
#12 0x00000000018681a7 in do_compile (no_backend=false) at
/home/marxin/Programming/gcc/gcc/toplev.cc:2153
#13 0x00000000018685d2 in toplev::main (this=0x7fffffffdb5a, argc=20,
argv=0x7fffffffdc88) at /home/marxin/Programming/gcc/gcc/toplev.cc:2320
#14 0x0000000002bdc260 in main (argc=20, argv=0x7fffffffdc88) at
/home/marxin/Programming/gcc/gcc/main.cc:39

It's called at the time when current_class_stack_size == 0 which explain the
ICE.

The variable is initialized in   init_class_processing (), which is also called
from cxx_init_decl_processing (void), but later.

CCint Przemyslaw

[Bug target/104409] -march=armv8.6-a+ls64 crashes, LS64 builtins causes ICE

[wirkus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104409

Przemyslaw Wirkus <wirkus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |wirkus at gcc dot gnu.org

--- Comment #7 from Przemyslaw Wirkus <wirkus at gcc dot gnu.org> ---
That you all for the analysis. 
I will try to sort it out, cheers!

[Bug target/104409] [12 Regression] -march=armv8.6-a+ls64 crashes, LS64 builtins causes ICE

[tnfchris at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104409

Tamar Christina <tnfchris at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|-march=armv8.6-a+ls64       |[12 Regression]
                   |crashes, LS64 builtins      |-march=armv8.6-a+ls64
                   |causes ICE                  |crashes, LS64 builtins
                   |                            |causes ICE
           Assignee|wirkus at gcc dot gnu.org          |tnfchris at gcc dot gnu.org
           Priority|P3                          |P1
                 CC|                            |tnfchris at gcc dot gnu.org
   Target Milestone|---                         |12.0

--- Comment #8 from Tamar Christina <tnfchris at gcc dot gnu.org> ---
Testing patch.

[Bug target/104409] [12 Regression] -march=armv8.6-a+ls64 crashes, LS64 builtins causes ICE

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104409

--- Comment #9 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Tamar Christina <tnfchris@gcc.gnu.org>:

https://gcc.gnu.org/g:af3cadb59fe6cb2097d2e636c1c70b26df39ae19

commit r12-8049-gaf3cadb59fe6cb2097d2e636c1c70b26df39ae19
Author: Tamar Christina <tamar.christina@arm.com>
Date:   Thu Apr 7 16:48:05 2022 +0100

    AArch64: fix ls64 intrinsics expansion [PR104409]

    The LS64 intrinsics used a machinery that's not safe to use unless being
    called from a pragma instantiation.

    This moves the initialization code to a new pragma for arm_acle.h.

    gcc/ChangeLog:

            PR target/104409
            * config/aarch64/aarch64-builtins.cc (handle_arm_acle_h): New.
            (aarch64_general_init_builtins): Move LS64 code.
            * config/aarch64/aarch64-c.cc (aarch64_pragma_aarch64): Support
            arm_acle.h
            * config/aarch64/aarch64-protos.h (handle_arm_acle_h): New.
            * config/aarch64/arm_acle.h: Add pragma GCC aarch64 "arm_acle.h".

[Bug target/104409] [12 Regression] -march=armv8.6-a+ls64 crashes, LS64 builtins causes ICE

[tnfchris at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104409

Tamar Christina <tnfchris at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|NEW                         |RESOLVED

--- Comment #10 from Tamar Christina <tnfchris at gcc dot gnu.org> ---
Fixed, thanks for the report.