When compiling attached unit test with -O3, it fails on sse2 test. With any other optimization level including -O2 plus: -fgcse-after-reload -finline-functions -fipa-cp-clone -fpredictive-commoning -ftree-vectorize -funswitch-loops which should be the same as -O3, it passes unit test succesfully.
Gentoo x86_64, with gcc-4.4 and 4.3.2 Project page: http://volnitsky/project/lvvlib Source: http://github.com/lvv/lvvlib u-array.ii.gz attached. --------------------------------------------------------- g++ u-array.cc -o u-array -Wall -DID='"081214_183302-��g++-4.4.0-OPTIMIZE-0e541970++M"' -I ~/p/ -I /usr/local/include -DNDEBUG -DGSL_RANGE_CHECK_OFF -DNOCHECK -pipe -Wno-reorder -Wno-sign-compare -O3 -march=native -fwhole-program --combine -fopenmp -fomit-frame-pointer -funsafe-loop-optimizations -DGCC_BUG -O3 -v -Wno-unused-variable -Wno-unused-variable Using built-in specs. Target: x86_64-unknown-linux-gnu Configured with: ./configure : (reconfigured) ./configure --disable-bootstrap --enable-languages=c,c++,fortran --enable-multilib Thread model: posix gcc version 4.4.0 20081208 (experimental) (GCC) COLLECT_GCC_OPTIONS='-o' 'u-array' '-Wall' '-DID="081214_183302-��g++-4.4.0-OPTIMIZE-0e541970++M"' '-I' '/home/lvv/p/' '-I' '/usr/local/include' '-DNDEBUG' '-DGSL_RANGE_CHECK_OFF' '-DNOCHECK' '-pipe' '-Wno-reorder' '-Wno-sign-compare' '-O3' '-fwhole-program' '-combine' '-fopenmp' '-fomit-frame-pointer' '-funsafe-loop-optimizations' '-DGCC_BUG' '-O3' '-v' '-Wno-unused-variable' '-shared-libgcc' '-pthread' /usr/local/libexec/gcc/x86_64-unknown-linux-gnu/4.4.0/cc1plus -quiet -v -I /home/lvv/p/ -I /usr/local/include -D_GNU_SOURCE -D_REENTRANT -DID="081214_183302-��g++-4.4.0-OPTIMIZE-0e541970++M" -DNDEBUG -DGSL_RANGE_CHECK_OFF -DNOCHECK -DGCC_BUG u-array.cc -march=core2 -mcx16 -msahf --param l1-cache-size=32 --param l1-cache-line-size=64 --param l2-cache-size=4096 -mtune=core2 -quiet -dumpbase u-array.cc -auxbase u-array -O3 -O3 -Wall -Wno-reorder -Wno-sign-compare -Wno-unused-variable -version -fwhole-program -fopenmp -fomit-frame-pointer -funsafe-loop-optimizations -o - | as -V -Qy -o /tmp/ccO8IZrX.o - GNU assembler version 2.18 (x86_64-pc-linux-gnu) using BFD version (GNU Binutils) 2.18 ignoring nonexistent directory "/usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/../../../../x86_64-unknown-linux-gnu/include" ignoring duplicate directory "/usr/local/include" as it is a non-system directory that duplicates a system directory ignoring duplicate directory "/usr/local/include" as it is a non-system directory that duplicates a system directory #include "..." search starts here: #include <...> search starts here: /home/lvv/p/ /usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/../../../../include/c++/4.4.0 /usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/../../../../include/c++/4.4.0/x86_64-unknown-linux-gnu /usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/../../../../include/c++/4.4.0/backward /usr/local/include /usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/include /usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/include-fixed /usr/include End of search list. GNU C++ (GCC) version 4.4.0 20081208 (experimental) (x86_64-unknown-linux-gnu) compiled by GNU C version 4.4.0 20081115 (experimental), GMP version 4.2.4, MPFR version 2.3.2. GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096 Compiler executable checksum: f0165b2e8081c04e24b530c99a2b0b81 COMPILER_PATH=/usr/local/libexec/gcc/x86_64-unknown-linux-gnu/4.4.0/:/usr/local/libexec/gcc/x86_64-unknown-linux-gnu/4.4.0/:/usr/local/libexec/gcc/x86_64-unknown-linux-gnu/:/usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/:/usr/local/lib/gcc/x86_64-unknown-linux-gnu/ LIBRARY_PATH=/usr/local/lib/../lib64/:/usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/:/usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/../../../../lib64/:/lib/../lib64/:/usr/lib/../lib64/:./:/usr/local/lib/:/usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/../../../:/lib/:/usr/lib/ Reading specs from /usr/local/lib/../lib64/libgomp.spec COLLECT_GCC_OPTIONS='-o' 'u-array' '-Wall' '-DID="081214_183302-��g++-4.4.0-OPTIMIZE-0e541970++M"' '-I' '/home/lvv/p/' '-I' '/usr/local/include' '-DNDEBUG' '-DGSL_RANGE_CHECK_OFF' '-DNOCHECK' '-pipe' '-Wno-reorder' '-Wno-sign-compare' '-O3' '-fwhole-program' '-combine' '-fopenmp' '-fomit-frame-pointer' '-funsafe-loop-optimizations' '-DGCC_BUG' '-O3' '-v' '-Wno-unused-variable' '-shared-libgcc' '-pthread' /usr/local/libexec/gcc/x86_64-unknown-linux-gnu/4.4.0/collect2 --eh-frame-hdr -m elf_x86_64 -dynamic-linker /lib64/ld-linux-x86-64.so.2 -o u-array /usr/lib/../lib64/crt1.o /usr/lib/../lib64/crti.o /usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/crtbegin.o -L/usr/local/lib/../lib64 -L/usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0 -L/usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/../../../../lib64 -L/lib/../lib64 -L/usr/lib/../lib64 -L. -L/usr/local/lib -L/usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/../../.. /tmp/ccO8IZrX.o -lstdc++ -lm -lgomp -lgcc_s -lgcc -lpthread -lc -lgcc_s -lgcc /usr/local/lib/gcc/x86_64-unknown-linux-gnu/4.4.0/crtend.o /usr/lib/../lib64/crtn.o -- Summary: sse2(int16) code fails with -O3 Product: gcc Version: 4.4.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: leonid at volnitsky dot com GCC host triplet: x86_64-unknown-linux-gnu GCC target triplet: x86_64-unknown-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38525
