include/asm-generic/bitops/builtin-fls.h

File Facts

System

Linux kernel

Corpus path

include/asm-generic/bitops/builtin-fls.h

Extension

.h

Size

432 bytes

Lines

18

Domain

Repository Root And Misc

Bucket

include

Inferred role

Repository Root And Misc: implementation source

Status

source implementation candidate

Why This File Exists

Top-level or miscellaneous repository surface. Use this as map coverage unless a later manual pass promotes the file into a deeper subsystem dossier.

• Top-level or miscellaneous repository surface. Use this as map coverage unless a later manual pass promotes the file into a deeper subsystem dossier.

Dependency Surface

• No C-style include directives detected by the generator.

Detected Declarations

• function fls

Annotated Snippet

#ifndef _ASM_GENERIC_BITOPS_BUILTIN_FLS_H_
#define _ASM_GENERIC_BITOPS_BUILTIN_FLS_H_

/**
 * fls - find last (most-significant) bit set
 * @x: the word to search
 *
 * This is defined the same way as ffs.
 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
 */
static __always_inline __attribute_const__ int fls(unsigned int x)
{
	return x ? sizeof(x) * 8 - __builtin_clz(x) : 0;
}

#endif

Annotation

• Detected declarations: `function fls`.
• Atlas domain: Repository Root And Misc / include.
• Implementation status: source implementation candidate.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.