------- Comment #14 from jv244 at cam dot ac dot uk 2009-09-01 06:56 ------- I wanted to try Vladimir Makarov's new patch for this testcase, but on an unpatched trunk I notice a serious runtime regression with '-fschedule-insns' with respect to 4.3.3
Using as base options (for the attached testcase) gfortran -O3 -march=native -funroll-loops -ffast-math test.f90 4.3.3 w -fschedule-insns : 3.372s 4.3.3 w/o -fschedule-insns : 4.384s 4.4.2 w -fschedule-insns : 4.748s 4.4.2 w/o -fschedule-insns : 4.408s 4.5.0 w -fschedule-insns : 4.712s 4.5.0 w/o -fschedule-insns : 4.408s so 4.3 against 4.5 'w -fschedule-insns' is about 40% faster. I guess this is pretty target specific, I'm running this on an Opteron, this is what -v reports: Target: x86_64-unknown-linux-gnu Configured with: /data03/vondele/gcc_trunk/gcc/configure --disable-bootstrap --prefix=/data03/vondele/gcc_trunk/build --enable-languages=c,c++,fortran --disable-multilib --with-ppl=/data03/vondele/gcc_trunk/build/ --with-cloog=/data03/vondele/gcc_trunk/build/ Thread model: posix gcc version 4.5.0 20090830 (experimental) [trunk revision 151229] (GCC) COLLECT_GCC_OPTIONS='-O3' '-funroll-loops' '-ffast-math' '-fschedule-insns' '-v' '-shared-libgcc' /data03/vondele/gcc_trunk/build/libexec/gcc/x86_64-unknown-linux-gnu/4.5.0/f951 test.f90 -march=k8-sse3 -mcx16 -msahf --param l1-cache-size=64 --param l1-cache-line-size=64 --param l2-cache-size=1024 -mtune=k8 -quiet -dumpbase test.f90 -auxbase test -O3 -version -funroll-loops -ffast-math -fschedule-insns -fintrinsic-modules-path /data03/vondele/gcc_trunk/build/lib/gcc/x86_64-unknown-linux-gnu/4.5.0/finclude -o /tmp/ccvGq2CO.s -- jv244 at cam dot ac dot uk changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |vmakarov at redhat dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38306