arch/csky/abiv2/strlen.S

File Facts

System

Linux kernel

Corpus path

arch/csky/abiv2/strlen.S

Extension

.S

Size

1481 bytes

Lines

98

Domain

Architecture Layer

Bucket

arch/csky

Inferred role

Architecture Layer: arch/csky

Status

atlas-only

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.

Dependency Surface

• linux/linkage.h
• sysdep.h

Detected Declarations

• No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.

#include <linux/linkage.h>
#include "sysdep.h"

ENTRY(strlen)
	/* Check if the start addr is aligned.  */
	mov	r3, r0
	andi	r1, r0, 3
	movi	r2, 4
	movi	r0, 0
	bnez	r1, .L_start_not_aligned

	LABLE_ALIGN
.L_start_addr_aligned:
	/* Check if all the bytes in the word are not zero.  */
	ldw	r1, (r3)
	tstnbz	r1
	bf	.L_string_tail

	ldw	r1, (r3, 4)
	addi	r0, 4
	tstnbz	r1
	bf	.L_string_tail

	ldw	r1, (r3, 8)
	addi	r0, 4
	tstnbz	r1
	bf	.L_string_tail

	ldw	r1, (r3, 12)
	addi	r0, 4
	tstnbz	r1
	bf	.L_string_tail

	ldw	r1, (r3, 16)
	addi	r0, 4
	tstnbz	r1
	bf	.L_string_tail

	ldw	r1, (r3, 20)
	addi	r0, 4
	tstnbz	r1
	bf	.L_string_tail

	ldw	r1, (r3, 24)
	addi	r0, 4
	tstnbz	r1
	bf	.L_string_tail

	ldw	r1, (r3, 28)
	addi	r0, 4
	tstnbz	r1
	bf	.L_string_tail

	addi	r0, 4
	addi	r3, 32
	br	.L_start_addr_aligned

.L_string_tail:
# ifdef __CSKYBE__
	xtrb0	r3, r1
	bez	r3, .L_return
	addi	r0, 1
	xtrb1	r3, r1
	bez	r3, .L_return
	addi	r0, 1
	xtrb2	r3, r1
	bez	r3, .L_return
	addi	r0, 1

Annotation

• Immediate include surface: `linux/linkage.h`, `sysdep.h`.
• Atlas domain: Architecture Layer / arch/csky.
• Implementation status: atlas-only.

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.