From 5278f6def4248391a481382bd7b0042b04c829f2 Mon Sep 17 00:00:00 2001 From: Richard Qin Date: Tue, 21 Apr 2026 23:16:50 +0800 Subject: feat: add string manipulation functions derived from musl libc This commit introduces a variety of string manipulation functions, including: - `memmem`: Searches for a substring in a memory area. - `memmove`: Safely copies memory areas, handling overlaps. - `mempcpy`: Copies memory and returns a pointer to the end of the destination. - `memrchr`: Finds the last occurrence of a character in a memory area. - `memset`: Fills a memory area with a specified value. - `rindex`: Returns the last occurrence of a character in a string. - `stpcpy` and `stpncpy`: Copies strings and returns a pointer to the end. - `strcat`, `strchr`, `strcspn`, `strlcat`, `strlcpy`, `strlen`, `strncat`, `strncmp`, `strncpy`, `strnlen`, `strpbrk`, `strrchr`, `strstr`, `strtok`, and `strtok_r`: Various string manipulation functions for concatenation, searching, and tokenization. Assembly implementations for `memcpy`, `memmove`, and `memset` are also included for optimized performance on x86_64 architectures. --- na/lib/string/arm/__aeabi_memcpy.s | 45 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 na/lib/string/arm/__aeabi_memcpy.s (limited to 'na/lib/string/arm/__aeabi_memcpy.s') diff --git a/na/lib/string/arm/__aeabi_memcpy.s b/na/lib/string/arm/__aeabi_memcpy.s new file mode 100644 index 0000000..3a527e4 --- /dev/null +++ b/na/lib/string/arm/__aeabi_memcpy.s @@ -0,0 +1,45 @@ +.syntax unified + +.global __aeabi_memcpy8 +.global __aeabi_memcpy4 +.global __aeabi_memcpy +.global __aeabi_memmove8 +.global __aeabi_memmove4 +.global __aeabi_memmove + +.type __aeabi_memcpy8,%function +.type __aeabi_memcpy4,%function +.type __aeabi_memcpy,%function +.type __aeabi_memmove8,%function +.type __aeabi_memmove4,%function +.type __aeabi_memmove,%function + +__aeabi_memmove8: +__aeabi_memmove4: +__aeabi_memmove: + cmp r0, r1 + bls 3f + cmp r2, #0 + beq 2f + adds r0, r0, r2 + adds r2, r1, r2 +1: subs r2, r2, #1 + ldrb r3, [r2] + subs r0, r0, #1 + strb r3, [r0] + cmp r1, r2 + bne 1b +2: bx lr +__aeabi_memcpy8: +__aeabi_memcpy4: +__aeabi_memcpy: +3: cmp r2, #0 + beq 2f + adds r2, r1, r2 +1: ldrb r3, [r1] + adds r1, r1, #1 + strb r3, [r0] + adds r0, r0, #1 + cmp r1, r2 + bne 1b +2: bx lr -- cgit v1.2.3