tree 7aa5ccb6bf8649c801e3e3c66146fe6325a641a6
parent 3fa19d7ff89be87139e2864fb9186b424d180a58
author Tim Peters <tim.peters@gmail.com> 1093918795 +0000
committer Tim Peters <tim.peters@gmail.com> 1093918795 +0000
HG:extra convert_revision:svn%3A6015fed2-1504-0410-9fe1-9d1591cc4771/python/branches/legacy-trunk%4037214

HardwareRandom:  Go back to multiplying by 2**-BPF instead of using
ldexp.  Both methods are exact, and return the same results.  Turns out
multiplication is a few (but just a few) percent faster on my box.
They're both significantly faster than using struct with a Q format
to convert bytes to a 64-bit long (struct.unpack() appears to lose due
to the tuple creation/teardown overhead), and calling _hexlify is
significantly faster than doing bytes.encode('hex').  So we appear to
have hit a local minimum (wrt speed) here.