cpuinfo2cpuflags (guess CPU_FLAGS_X86 flags for the host)

cpuinfo2cpuflags is a tool to guess CPU_FLAGS_X86 flags for the host.

Call the cpuid instruction to obtain the supported CPU feature bits
instead of reading the preprocessed values from Linux-specific 
/proc/cpuinfo. This increases portability across systems and accuracy of
information -- supported instructions depend on the version of the
program rather than the Linux kernel.