This check-in also enables the 64-bit RDRAND routines for X32. The changes were with held until they could be tested. The testing occurred with Issue 395
Port rdrand.S to Solaris
Port rdrand.S to X32
The X32 port is responsible for the loop unwinding. The unwind generates a 32-byte block (X64 and X32) or 16-byte block (X86). On X32, it increases throughut by 100% (doubles it). On X86 and X64, throughput increases by about 6%. Anything over 4 machine words slows things down.
Port rdrand.S to Cygwin and OS X
Add DISABLE_NATIVE_ARCH to CmakefileList and GNUmakefile. It supresses the addition of -march=native. DISABLE_NATIVE_ARCH replaces DISABLE_CXXFLAGS_OPTIMIZATIONS in CmakefileList (the latter is now deprecated).