From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 052FF3858038; Wed, 30 Dec 2020 19:13:11 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 052FF3858038 From: "toiwoton at gmail dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug c/98482] New: -mfentry creates invalid call for -mcmodel=large Date: Wed, 30 Dec 2020 19:13:10 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: c X-Bugzilla-Version: 10.2.1 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: toiwoton at gmail dot com X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status bug_severity priority component assigned_to reporter target_milestone Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: gcc-bugs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-bugs mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 30 Dec 2020 19:13:11 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D98482 Bug ID: 98482 Summary: -mfentry creates invalid call for -mcmodel=3Dlarge Product: gcc Version: 10.2.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: toiwoton at gmail dot com Target Milestone: --- GCC on x86_64 with `-mfentry` generates invalid code for `-mcmodel=3Dlarge`= . The call to `__fentry__` uses plain `call` instruction, but this can only addre= ss locations within 32 bit range while the target may be anywhere in the 64 bit range due to `-mcmodel=3Dlarge`. The expected code would be something which loads a 64 bit value to a regist= er and then uses register indirect call, so instead of call __fentry__ there needs to be movabsq $__fentry__, %rax call *%rax $ gcc -v Using built-in specs. COLLECT_GCC=3Dgcc COLLECT_LTO_WRAPPER=3D/usr/lib/gcc/x86_64-linux-gnu/10/lto-wrapper OFFLOAD_TARGET_NAMES=3Dnvptx-none:amdgcn-amdhsa:hsa OFFLOAD_TARGET_DEFAULT=3D1 Target: x86_64-linux-gnu Configured with: ../src/configure -v --with-pkgversion=3D'Debian 10.2.1-3' --with-bugurl=3Dfile:///usr/share/doc/gcc-10/README.Bugs --enable-languages=3Dc,ada,c++,go,brig,d,fortran,objc,obj-c++,m2 --prefix= =3D/usr --with-gcc-major-version-only --program-suffix=3D-10 --program-prefix=3Dx86_64-linux-gnu- --enable-shared --enable-linker-build-= id --libexecdir=3D/usr/lib --without-included-gettext --enable-threads=3Dposix --libdir=3D/usr/lib --enable-nls --enable-bootstrap --enable-clocale=3Dgnu --enable-libstdcxx-debug --enable-libstdcxx-time=3Dyes --with-default-libstdcxx-abi=3Dnew --enable-gnu-unique-object --disable-vtable-verify --enable-plugin --enable-default-pie --with-system-= zlib --enable-libphobos-checking=3Drelease --with-target-system-zlib=3Dauto --enable-objc-gc=3Dauto --enable-multiarch --disable-werror --with-arch-32= =3Di686 --with-abi=3Dm64 --with-multilib-list=3Dm32,m64,mx32 --enable-multilib --with-tune=3Dgeneric --enable-offload-targets=3Dnvptx-none=3D/build/gcc-10-0py4jQ/gcc-10-10.2.1/= debian/tmp-nvptx/usr,amdgcn-amdhsa=3D/build/gcc-10-0py4jQ/gcc-10-10.2.1/deb= ian/tmp-gcn/usr,hsa --without-cuda-driver --enable-checking=3Drelease --build=3Dx86_64-linux-gnu --host=3Dx86_64-linux-gnu --target=3Dx86_64-linux-gnu --with-build-config=3Dbootstrap-lto-lean --enable-link-mutex Thread model: posix Supported LTO compression algorithms: zlib zstd gcc version 10.2.1 20201224 (Debian 10.2.1-3)=20 $ cat mfentry.c void func(void) { } $ gcc -mfentry -pg -S mfentry.c -mcmodel=3Dlarge -fno-pie -O2 -save-temps $ cat mfentry.i # 1 "mfentry.c" # 1 "" # 1 "" # 31 "" # 1 "/usr/include/stdc-predef.h" 1 3 4 # 32 "" 2 # 1 "mfentry.c" void func(void) { } $ cat mfentry.s .file "mfentry.c" .text .p2align 4 .globl func .type func, @function func: .LFB0: .cfi_startproc 1: call __fentry__ ret .cfi_endproc .LFE0: .size func, .-func .ident "GCC: (Debian 10.2.1-3) 10.2.1 20201224" .section .note.GNU-stack,"",@progbits=