From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 58D6A3858C83; Tue, 19 Apr 2022 16:05:10 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 58D6A3858C83 From: "570070308 at qq dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug c/105311] New: [12]Still generate memset even with -fno-tree-loop-distribute-patterns Date: Tue, 19 Apr 2022 16:05:10 +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: 12.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: 570070308 at qq 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: Tue, 19 Apr 2022 16:05:10 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105311 Bug ID: 105311 Summary: [12]Still generate memset even with -fno-tree-loop-distribute-patterns Product: gcc Version: 12.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: 570070308 at qq dot com Target Milestone: --- I have read the https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D56888 , acco= rding to this, adding `-fno-tree-loop-distribute-patterns` will prevent gcc from calling memset. However, the gcc still call memset with the code below: ```test.c #include struct Page_Table_Page { uint64_t pts[511][512]; }; void init_ptp(struct Page_Table_Page*const ptp) { *ptp=3D(struct Page_Table_Page){{{0}}}; } ``` compile with: ``` gcc-12 -O3 test.c -S -fno-tree-loop-distribute-patterns -fno-builtin-memset -fno-builtin -nodefaultlibs -nostdlib -ffreestanding ``` ```test.s init_ptp: .LFB24: .cfi_startproc endbr64 subq $8, %rsp .cfi_def_cfa_offset 16 movl $2093056, %edx xorl %esi, %esi call memset@PLT addq $8, %rsp .cfi_def_cfa_offset 8 ret ``` The gcc-12 is installed by apt on Ubuntu 22.04. The full compile log: ``` $ gcc-12 -O3 test.c -S -fno-tree-loop-distribute-patterns -fno-builtin-mems= et -fno-builtin -nodefaultlibs -nostdlib -ffreestanding -v Using built-in specs. COLLECT_GCC=3Dgcc-12 OFFLOAD_TARGET_NAMES=3Dnvptx-none:amdgcn-amdhsa OFFLOAD_TARGET_DEFAULT=3D1 Target: x86_64-linux-gnu Configured with: ../src/configure -v --with-pkgversion=3D'Ubuntu 12-20220319-1ubuntu1' --with-bugurl=3Dfile:///usr/share/doc/gcc-12/README.B= ugs --enable-languages=3Dc,ada,c++,go,d,fortran,objc,obj-c++,m2 --prefix=3D/usr --with-gcc-major-version-only --program-suffix=3D-12 --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-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=3Drelea= se --with-target-system-zlib=3Dauto --enable-objc-gc=3Dauto --enable-multiarch --disable-werror --enable-cet --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-12-OcsLtf/gcc-12-12-2022= 0319/debian/tmp-nvptx/usr,amdgcn-amdhsa=3D/build/gcc-12-OcsLtf/gcc-12-12-20= 220319/debian/tmp-gcn/usr --enable-offload-defaulted --without-cuda-driver --enable-checking=3Drelease --build=3Dx86_64-linux-gnu --host=3Dx86_64-linux-gnu --target=3Dx86_64-linu= x-gnu Thread model: posix Supported LTO compression algorithms: zlib zstd gcc version 12.0.1 20220319 (experimental) [master r12-7719-g8ca61ad148f] (Ubuntu 12-20220319-1ubuntu1)=20 COLLECT_GCC_OPTIONS=3D'-O3' '-S' '-fno-tree-loop-distribute-patterns' '-fno-builtin-memset' '-fno-builtin' '-nodefaultlibs' '-nostdlib' '-ffreestanding' '-v' '-mtune=3Dgeneric' '-march=3Dx86-64' /usr/lib/gcc/x86_64-linux-gnu/12/cc1 -quiet -v -imultiarch x86_64-linux-gnu test.c -quiet -dumpbase test.c -dumpbase-ext .c -mtune=3Dgeneric -march=3Dx= 86-64 -O3 -version -fno-tree-loop-distribute-patterns -fno-builtin-memset -fno-builtin -ffreestanding -o test.s -fasynchronous-unwind-tables -Wformat -Wformat-security -fstack-clash-protection -fcf-protection GNU C17 (Ubuntu 12-20220319-1ubuntu1) version 12.0.1 20220319 (experimental) [master r12-7719-g8ca61ad148f] (x86_64-linux-gnu) compiled by GNU C version 12.0.1 20220319 (experimental) [master r12-7719-g8ca61ad148f], GMP version 6.2.1, MPFR version 4.1.0, MPC version 1.2.1, isl version isl-0.24-GMP GGC heuristics: --param ggc-min-expand=3D100 --param ggc-min-heapsize=3D131= 072 ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu" ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux-gnu/12/include-fi= xed" ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux-gnu/12/../../../../x86_64-linux-gnu/include" #include "..." search starts here: #include <...> search starts here: /usr/lib/gcc/x86_64-linux-gnu/12/include /usr/local/include /usr/include/x86_64-linux-gnu /usr/include End of search list. GNU C17 (Ubuntu 12-20220319-1ubuntu1) version 12.0.1 20220319 (experimental) [master r12-7719-g8ca61ad148f] (x86_64-linux-gnu) compiled by GNU C version 12.0.1 20220319 (experimental) [master r12-7719-g8ca61ad148f], GMP version 6.2.1, MPFR version 4.1.0, MPC version 1.2.1, isl version isl-0.24-GMP GGC heuristics: --param ggc-min-expand=3D100 --param ggc-min-heapsize=3D131= 072 Compiler executable checksum: 200a3dd46f0674d1a8fcf2b133bc6014 COMPILER_PATH=3D/usr/lib/gcc/x86_64-linux-gnu/12/:/usr/lib/gcc/x86_64-linux= -gnu/12/:/usr/lib/gcc/x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/12/:/= usr/lib/gcc/x86_64-linux-gnu/ LIBRARY_PATH=3D/usr/lib/gcc/x86_64-linux-gnu/12/:/usr/lib/gcc/x86_64-linux-= gnu/12/../../../x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/12/../../..= /../lib/:/lib/x86_64-linux-gnu/:/lib/../lib/:/usr/lib/x86_64-linux-gnu/:/us= r/lib/../lib/:/usr/lib/gcc/x86_64-linux-gnu/12/../../../:/lib/:/usr/lib/ COLLECT_GCC_OPTIONS=3D'-O3' '-S' '-fno-tree-loop-distribute-patterns' '-fno-builtin-memset' '-fno-builtin' '-nodefaultlibs' '-nostdlib' '-ffreestanding' '-v' '-mtune=3Dgeneric' '-march=3Dx86-64' ```=