Skip to end of metadata
  • Created by Former user , last modified by Former user on Jan 01, 2014
Go to start of metadata

You are viewing an old version of this page. View the current version.

Compare with Current View Page History

« Previous Version 12 Next »

Description

Counts the number of contiguous, most-significant, leading zero bits in a data value. If available on the targeted architecture an alternate optimized implementation can be defined.

Files

cpu_core.h/cpu_core.c / Specific CPU/compiler cpu_a.asm

Prototypes

Arguments

val

Data value to count leading zero bits.

Returned Value

Number of contiguous, most-significant, leading zero bits in val.

Required Configuration

CPU_CntLeadZeros()is available and implemented in cpu_core.c if CPU_CFG_LEAD_ZEROS_ASM_PRESENT is not #define'd in cpu_cfg.h (or cpu.h), but should be implemented in cpu_a.asm (or cpu_a.s) if CPU_CFG_LEAD_ZEROS_ASM_PRESENT is #define'd in cpu_cfg.h (or cpu.h). Refer to Core Library Configuration for details.

Each CPU_CntLeadZerosXX() is available and implemented in cpu_core.c based on CPU_CFG_DATA_SIZE_MAX configuration as #define'd in cpu.h :

Functions available according to CPU_CFG_DATA_SIZE_MAX:

CPU_CntLeadZero08() = CPU_WORD_SIZE_08
CPU_CntLeadZero16() = CPU_WORD_SIZE_16
CPU_CntLeadZero32() = CPU_WORD_SIZE_32
CPU_CntLeadZero64() = CPU_WORD_SIZE_64

Notes / Warnings

None.

Example Usage

  • No labels