Remove building with NOCRYPTO option
[minix.git] / lib / libc / arch / x86_64 / string / swab.S
blob636cb43281f400d58db9da4e126b7ada912fe1da
1 /*
2  * Written by J.T. Conklin <jtc@NetBSD.org>.
3  * Public domain.
4  */
6 #include <machine/asm.h>
8 #if defined(LIBC_SCCS)
9         RCSID("$NetBSD: swab.S,v 1.4 2014/05/22 15:01:57 uebayasi Exp $")
10 #endif
12 #define LOAD_SWAP_STORE_WORD \
13         lodsw   ; \
14         xchgb   %al,%ah ; \
15         stosw
17 ENTRY(swab)
18         xchgq   %rdi,%rsi
19         cld                             # set direction forward
21         shrq    $1,%rdx
22         testq   $7,%rdx                 # copy first group of 1 to 7 words
23         jz      L2                      # while swapping alternate bytes.
24 L1:     lodsw
25         rorw    $8,%ax
26         stosw
27         decq    %rdx
28         testq   $7,%rdx
29         jnz     L1
31 L2:     shrq    $3,%rdx                 # copy remainder 8 words at a time
32         jz      L4                      # while swapping alternate bytes.
33 L3:
34         LOAD_SWAP_STORE_WORD
35         LOAD_SWAP_STORE_WORD
36         LOAD_SWAP_STORE_WORD
37         LOAD_SWAP_STORE_WORD
38         LOAD_SWAP_STORE_WORD
39         LOAD_SWAP_STORE_WORD
40         LOAD_SWAP_STORE_WORD
41         LOAD_SWAP_STORE_WORD
43         decq    %rdx
44         jnz     L3
45 L4:
46         ret
47 END(swab)