arch/xtensa/lib/ashldi3.S

File Facts

System

Linux kernel

Corpus path

arch/xtensa/lib/ashldi3.S

Extension

.S

Size

472 bytes

Lines

30

Domain

Architecture Layer

Bucket

arch/xtensa

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/asmmacro.h
• asm/core.h

Detected Declarations

• export __ashldi3

Annotated Snippet

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

#ifdef __XTENSA_EB__
#define uh a2
#define ul a3
#else
#define uh a3
#define ul a2
#endif /* __XTENSA_EB__ */

ENTRY(__ashldi3)

	abi_entry_default
	ssl	a4
	bgei	a4, 32, .Llow_only
	src	uh, uh, ul
	sll	ul, ul
	abi_ret_default

.Llow_only:
	sll	uh, ul
	movi	ul, 0
	abi_ret_default

ENDPROC(__ashldi3)
EXPORT_SYMBOL(__ashldi3)

Annotation

• Immediate include surface: `linux/linkage.h`, `asm/asmmacro.h`, `asm/core.h`.
• Detected declarations: `export __ashldi3`.
• Atlas domain: Architecture Layer / arch/xtensa.
• 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.