Requirements: poly1305aes_macos must be run on a PowerPC CPU, under MacOS X (as opposed to, e.g., AIX), inside a 32-bit program. It sets the CPU's floating-point mode to round-to-nearest; programs must not assume that the floating-point mode is preserved by function calls.
Here are the poly1305aes_macos files:
If you want to know how fast the code is, see my separate page of speed tables. If you want a rough idea of how the code works, see poly1305aes_53. If you want to know what improvements are possible in poly1305aes_macos, see the poly1305aes_aix discussion.