diff options
Diffstat (limited to 'string/aarch64/strlen.S')
| -rw-r--r-- | string/aarch64/strlen.S | 21 |
1 files changed, 7 insertions, 14 deletions
diff --git a/string/aarch64/strlen.S b/string/aarch64/strlen.S index a1b164a..6f6f08f 100644 --- a/string/aarch64/strlen.S +++ b/string/aarch64/strlen.S @@ -1,8 +1,8 @@ /* * strlen - calculate the length of a string. * - * Copyright (c) 2020, Arm Limited. - * SPDX-License-Identifier: MIT + * Copyright (c) 2020-2022, Arm Limited. + * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception */ /* Assumptions: @@ -11,7 +11,7 @@ * Not MTE compatible. */ -#include "../asmdefs.h" +#include "asmdefs.h" #define srcin x0 #define len x0 @@ -36,6 +36,7 @@ #define tmp x2 #define tmpw w2 #define synd x3 +#define syndw w3 #define shift x4 /* For the first 32 bytes, NUL detection works on the principle that @@ -110,7 +111,6 @@ ENTRY (__strlen_aarch64) add len, len, tmp1, lsr 3 ret - .p2align 3 /* Look for a NUL byte at offset 16..31 in the string. */ L(bytes16_31): ldp data1, data2, [srcin, 16] @@ -138,6 +138,7 @@ L(bytes16_31): add len, len, tmp1, lsr 3 ret + nop L(loop_entry): bic src, srcin, 31 @@ -153,18 +154,12 @@ L(loop): /* Low 32 bits of synd are non-zero if a NUL was found in datav1. */ cmeq maskv.16b, datav1.16b, 0 sub len, src, srcin - tst synd, 0xffffffff - b.ne 1f + cbnz syndw, 1f cmeq maskv.16b, datav2.16b, 0 add len, len, 16 1: /* Generate a bitmask and compute correct byte offset. */ -#ifdef __AARCH64EB__ - bic maskv.8h, 0xf0 -#else - bic maskv.8h, 0x0f, lsl 8 -#endif - umaxp maskv.16b, maskv.16b, maskv.16b + shrn maskv.8b, maskv.8h, 4 fmov synd, maskd #ifndef __AARCH64EB__ rbit synd, synd @@ -173,8 +168,6 @@ L(loop): add len, len, tmp, lsr 2 ret - .p2align 4 - L(page_cross): bic src, srcin, 31 mov tmpw, 0x0c03 |