Module `abm`

Advanced Bit Manipulation (ABM) instructions

The POPCNT and LZCNT have their own CPUID bits to indicate support.

The references are:

Intel 64 and IA-32 Architectures Software Developer's Manual Volume 2: Instruction Set Reference, A-Z.
AMD64 Architecture Programmer's Manual, Volume 3: General-Purpose and System Instructions.

Wikipedia provides a quick overview of the instructions available.

Functions

_lzcnt_u32 Counts the leading most significant zero bits.
_popcnt32 Counts the bits that are set.