diff options
| author | PikalaxALT <pikalaxalt@gmail.com> | 2017-12-15 09:38:53 -0500 |
|---|---|---|
| committer | PikalaxALT <pikalaxalt@gmail.com> | 2017-12-15 09:39:34 -0500 |
| commit | f95a4a932476be2ba99e2fd081e8d2bc6ea12813 (patch) | |
| tree | 75f67192cb2d7b7b575c94edda318e475239b63c /newlib/libc/machine/sh/memset.S | |
| parent | f60aca96985e68c7d8a52eb7bc955fb80e132f73 (diff) | |
Import newlib and create makefile
Diffstat (limited to 'newlib/libc/machine/sh/memset.S')
| -rw-r--r-- | newlib/libc/machine/sh/memset.S | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/newlib/libc/machine/sh/memset.S b/newlib/libc/machine/sh/memset.S new file mode 100644 index 0000000..7352b41 --- /dev/null +++ b/newlib/libc/machine/sh/memset.S @@ -0,0 +1,64 @@ +! +! Fast SH memset +! +! by Toshiyasu Morita (tm@netcom.com) +! +! Entry: r4: destination pointer +! r5: fill value +! r6: byte count +! +! Exit: r0-r3: trashed +! + +! This assumes that the first four bytes of the address space (0..3) are +! reserved - usually by the linker script. Otherwise, we would had to check +! for the case of objects of the size 12..15 at address 0..3 . + +#include "asm.h" + +ENTRY(memset) + mov #12,r0 ! Check for small number of bytes + cmp/gt r6,r0 + mov r4,r0 + SL(bt, L_store_byte_loop_check0, add r4,r6) + + tst #3,r0 ! Align destination + SL(bt, L_dup_bytes, extu.b r5,r5) + .balignw 4,0x0009 +L_align_loop: + mov.b r5,@r0 + add #1,r0 + tst #3,r0 + bf L_align_loop + +L_dup_bytes: + swap.b r5,r2 ! Duplicate bytes across longword + or r2,r5 + swap.w r5,r2 + or r2,r5 + + add #-16,r6 + + .balignw 4,0x0009 +L_store_long_loop: + mov.l r5,@r0 ! Store double longs to memory + cmp/hs r6,r0 + mov.l r5,@(4,r0) + SL(bf, L_store_long_loop, add #8,r0) + + add #16,r6 + +L_store_byte_loop_check0: + cmp/eq r6,r0 + bt L_exit + .balignw 4,0x0009 +L_store_byte_loop: + mov.b r5,@r0 ! Store bytes to memory + add #1,r0 + cmp/eq r6,r0 + bf L_store_byte_loop + +L_exit: + rts + mov r4,r0 + |