arch/riscv/lib/strchr.S

File Facts

System

Linux kernel

Corpus path

arch/riscv/lib/strchr.S

Extension

.S

Size

600 bytes

Lines

36

Domain

Architecture Layer

Bucket

arch/riscv

Inferred role

Architecture Layer: exported/initcall integration point

Status

integration implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

• CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
• Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.

Dependency Surface

• linux/linkage.h
• asm/asm.h

Detected Declarations

• export strchr

Annotated Snippet

#include <linux/linkage.h>
#include <asm/asm.h>

/* char *strchr(const char *s, int c) */
SYM_FUNC_START(strchr)
	/*
	 * Parameters
	 *   a0 - The string to be searched
	 *   a1 - The character to search for
	 *
	 * Returns
	 *   a0 - Address of first occurrence of 'c' or 0
	 *
	 * Clobbers
	 *   t0
	 */
	andi	a1, a1, 0xff
1:
	lbu	t0, 0(a0)
	beq	t0, a1, 2f
	addi	a0, a0, 1
	bnez	t0, 1b
	li	a0, 0
2:
	ret
SYM_FUNC_END(strchr)

SYM_FUNC_ALIAS_WEAK(__pi_strchr, strchr)
EXPORT_SYMBOL(strchr)

Annotation

• Immediate include surface: `linux/linkage.h`, `asm/asm.h`.
• Detected declarations: `export strchr`.
• Atlas domain: Architecture Layer / arch/riscv.
• Implementation status: integration 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.