This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: Faster compilation speed
Here's an interesting (aka depressing) data point. My previous
cache miss statistics were for GCC -O2. At -O0, GCC's cache miss
statistics stay the same or get up to 20% *worse*. In comparison, the
cache statistics for IBM's compiler without optimization enabled *improve*
up to 50 for the same reload.c and insn-recog.c input files compared to
optimized.
GCC has some sort of overhead, maybe the tree->RTL conversion as
Dan mentioned, which really hurts re-use at -O0.
David