| David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 2 | /* |
| 3 | * Based on arch/arm/lib/strchr.S |
| 4 | * |
| 5 | * Copyright (C) 1995-2000 Russell King |
| 6 | * Copyright (C) 2013 ARM Ltd. |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 7 | */ |
| 8 | |
| 9 | #include <linux/linkage.h> |
| 10 | #include <asm/assembler.h> |
| 11 | |
| 12 | /* |
| 13 | * Find the first occurrence of a character in a string. |
| 14 | * |
| 15 | * Parameters: |
| 16 | * x0 - str |
| 17 | * x1 - c |
| 18 | * Returns: |
| 19 | * x0 - address of first occurrence of 'c' or 0 |
| 20 | */ |
| David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 21 | WEAK(strchr) |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 22 | and w1, w1, #0xff |
| 23 | 1: ldrb w2, [x0], #1 |
| 24 | cmp w2, w1 |
| 25 | ccmp w2, wzr, #4, ne |
| 26 | b.ne 1b |
| 27 | sub x0, x0, #1 |
| 28 | cmp w2, w1 |
| 29 | csel x0, x0, xzr, eq |
| 30 | ret |
| 31 | ENDPROC(strchr) |
| David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 32 | EXPORT_SYMBOL_NOKASAN(strchr) |