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From: "oleg.endo@t-online.de" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug target/49468] New: SH Target: inefficient integer abs code Date: Sun, 19 Jun 2011 15:15:00 -0000 [thread overview] Message-ID: <bug-49468-4@http.gcc.gnu.org/bugzilla/> (raw) http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49468 Summary: SH Target: inefficient integer abs code Product: gcc Version: 4.7.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target AssignedTo: unassigned@gcc.gnu.org ReportedBy: oleg.endo@t-online.de The generated code for abs:SI and abs:DI is a bit inefficient: int abs (int i) { return (i < 0) ? -i : i; } mov r4,r1 shll r1 subc r1,r1 mov r1,r0 xor r4,r0 rts sub r1,r0 long long abs (long long i) { return (i < 0) ? -i : i; } mov r4,r3 shll r3 subc r3,r3 mov r5,r1 xor r3,r1 mov r3,r0 clrt xor r4,r0 subc r3,r1 rts subc r3,r0 There is a define_split in sh.md which is supposed to handle the special case for SH4 but it is not doing anything. The problem has been around since a couple of GCC 4.x versions. sh-elf-gcc -v Using built-in specs. COLLECT_GCC=sh-elf-gcc COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/sh-elf/4.7.0/lto-wrapper Target: sh-elf Configured with: ../gcc-trunk/configure --target=sh-elf --prefix=/usr/local --enable-languages=c,c++ --enable-multilib --disable-libssp --without-headers --disable-nls --disable-werror --enable-lto --with-newlib --with-gnu-as --with-gnu-ld --with-system-zlib : (reconfigured) ../gcc-trunk/configure --target=sh-elf --prefix=/usr/local --enable-languages=c,c++ --enable-multilib --disable-libssp --without-headers --disable-nls --disable-werror --enable-lto --with-newlib --with-gnu-as --with-gnu-ld --with-system-zlib : (reconfigured) ../gcc-trunk/configure --target=sh-elf --prefix=/usr/local --enable-languages=c,c++ --enable-multilib --disable-libssp --without-headers --disable-nls --disable-werror --enable-lto --with-newlib --with-gnu-as --with-gnu-ld --with-system-zlib : (reconfigured) ../gcc-trunk/configure --target=sh-elf --prefix=/usr/local --enable-multilib --disable-libssp --without-headers --disable-nls --disable-werror --enable-lto --with-newlib --with-gnu-as --with-gnu-ld --with-system-zlib target_alias=sh-elf CFLAGS=-Os CXXFLAGS=-Os --enable-languages=c,c++,lto --no-create --no-recursion Thread model: single gcc version 4.7.0 20110619 (experimental) (GCC)
next reply other threads:[~2011-06-19 15:15 UTC|newest] Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top 2011-06-19 15:15 oleg.endo@t-online.de [this message] 2011-06-19 15:30 ` [Bug target/49468] " oleg.endo@t-online.de 2011-06-19 15:49 ` oleg.endo@t-online.de 2011-06-22 22:38 ` kkojima at gcc dot gnu.org 2011-06-26 20:49 ` oleg.endo@t-online.de 2011-06-27 6:40 ` kkojima at gcc dot gnu.org 2011-06-29 1:37 ` oleg.endo@t-online.de 2011-09-25 12:53 ` oleg.endo@t-online.de 2012-02-26 23:38 ` olegendo at gcc dot gnu.org 2012-02-28 8:44 ` olegendo at gcc dot gnu.org 2012-02-29 23:23 ` kkojima at gcc dot gnu.org 2012-03-14 23:10 ` olegendo at gcc dot gnu.org 2013-12-05 19:26 ` olegendo at gcc dot gnu.org
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