diff options
Diffstat (limited to 'lib/libc/aarch64')
-rw-r--r-- | lib/libc/aarch64/memset.S | 64 | ||||
-rw-r--r-- | lib/libc/aarch64/setjmp.S | 61 |
2 files changed, 125 insertions, 0 deletions
diff --git a/lib/libc/aarch64/memset.S b/lib/libc/aarch64/memset.S new file mode 100644 index 0000000..0543704 --- /dev/null +++ b/lib/libc/aarch64/memset.S @@ -0,0 +1,64 @@ +/* + * Copyright (c) 2020, Arm Limited. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <asm_macros.S> + + .global memset + +/* ----------------------------------------------------------------------- + * void *memset(void *dst, int val, size_t count) + * + * Copy the value of 'val' (converted to an unsigned char) into + * each of the first 'count' characters of the object pointed to by 'dst'. + * + * Returns the value of 'dst'. + * ----------------------------------------------------------------------- + */ +func memset + cbz x2, exit /* exit if 'count' = 0 */ + mov x3, x0 /* keep x0 */ + tst x0, #7 + b.eq aligned /* 8-bytes aligned */ + + /* Unaligned 'dst' */ +unaligned: + strb w1, [x3], #1 + subs x2, x2, #1 + b.eq exit /* exit if 0 */ + tst x3, #7 + b.ne unaligned /* continue while unaligned */ + + /* 8-bytes aligned */ +aligned:cbz x1, x1_zero + bfi w1, w1, #8, #8 /* propagate 'val' */ + bfi w1, w1, #16, #16 + bfi x1, x1, #32, #32 + +x1_zero:ands x4, x2, #~0x3f + b.eq less_64 + +write_64: + .rept 4 + stp x1, x1, [x3], #16 /* write 64 bytes in a loop */ + .endr + subs x4, x4, #64 + b.ne write_64 +less_64:tbz w2, #5, less_32 /* < 32 bytes */ + stp x1, x1, [x3], #16 /* write 32 bytes */ + stp x1, x1, [x3], #16 +less_32:tbz w2, #4, less_16 /* < 16 bytes */ + stp x1, x1, [x3], #16 /* write 16 bytes */ +less_16:tbz w2, #3, less_8 /* < 8 bytes */ + str x1, [x3], #8 /* write 8 bytes */ +less_8: tbz w2, #2, less_4 /* < 4 bytes */ + str w1, [x3], #4 /* write 4 bytes */ +less_4: tbz w2, #1, less_2 /* < 2 bytes */ + strh w1, [x3], #2 /* write 2 bytes */ +less_2: tbz w2, #0, exit + strb w1, [x3] /* write 1 byte */ +exit: ret + +endfunc memset diff --git a/lib/libc/aarch64/setjmp.S b/lib/libc/aarch64/setjmp.S new file mode 100644 index 0000000..9cb31ea --- /dev/null +++ b/lib/libc/aarch64/setjmp.S @@ -0,0 +1,61 @@ +/* + * Copyright (c) 2018-2019, Arm Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <asm_macros.S> +#include <assert_macros.S> +#include <setjmp.h> + + .globl setjmp + .globl longjmp + +/* + * int setjmp(jmp_buf env); + */ +func setjmp + mov x7, sp + + stp x19, x20, [x0, #JMP_CTX_X19] + stp x21, x22, [x0, #JMP_CTX_X21] + stp x23, x24, [x0, #JMP_CTX_X23] + stp x25, x26, [x0, #JMP_CTX_X25] + stp x27, x28, [x0, #JMP_CTX_X27] + stp x29, x30, [x0, #JMP_CTX_X29] + stp x7, xzr, [x0, #JMP_CTX_SP] + + mov x0, #0 + ret +endfunc setjmp + + +/* + * void longjmp(jmp_buf env, int val); + */ +func longjmp + ldp x7, xzr, [x0, #JMP_CTX_SP] + +#if ENABLE_ASSERTIONS + /* + * Since we're unwinding the stack, assert that the stack being reset to + * is shallower. + */ + mov x19, sp + cmp x7, x19 + ASM_ASSERT(ge) +#endif + + ldp x19, x20, [x0, #JMP_CTX_X19] + ldp x21, x22, [x0, #JMP_CTX_X21] + ldp x23, x24, [x0, #JMP_CTX_X23] + ldp x25, x26, [x0, #JMP_CTX_X25] + ldp x27, x28, [x0, #JMP_CTX_X27] + ldp x29, x30, [x0, #JMP_CTX_X29] + + mov sp, x7 + + ands x0, x1, x1 /* Move val to x0 and set flags */ + cinc x0, x0, eq /* If val is 0, return 1 */ + ret +endfunc longjmp |