Navigation: Linux Kernel Driver DataBase - web LKDDB: Main index - A index         

CONFIG_ARCH_USE_BUILTIN_BSWAP

General informations

The Linux kernel configuration item CONFIG_ARCH_USE_BUILTIN_BSWAP:

• prompt:
• type: bool
• depends on: (none)
• defined in arch/Kconfig
• found in Linux kernels: 3.8–3.9, 3.10-rc+HEAD

Help text

Modern versions of GCC (since 4.4) have builtin functions for handling byte-swapping. Using these, instead of the old inline assembler that the architecture code provides in the __arch_bswapXX() macros, allows the compiler to see what's happening and offers more opportunity for optimisation. In particular, the compiler will be able to combine the byteswap with a nearby load or store and use load-and-swap or store-and-swap instructions if the architecture has them. It should almost *never* result in code which is worse than the hand-coded assembler in <asm/swab.h>. But just in case it does, the use of the builtins is optional.

Any architecture with load-and-swap or store-and-swap instructions should set this. And it shouldn't hurt to set it on architectures that don't have such instructions.

Hardware

LKDDb

Raw data from LKDDb:

• (none)

Sources

This page is automaticly generated with free (libre, open) software lkddb(see lkddb-sources).

The data is retrived from:

• Linux kernel
• Linux Kernel Driver DataBase (LKDDb)

Automatic links from google (and ads)

Custom Search

Popular queries: