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Eliminate an unneeded instruction that is a vestige of mechanical

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translation from i386.
This commit is contained in:
Alan Cox 2005-04-07 05:46:46 +00:00
parent 8d6f45f534
commit 0417d4e3e9
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=144733
1 changed files with 5 additions and 7 deletions
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12
lib/libc/amd64/string/bzero.S
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@ -12,8 +12,6 @@ __FBSDID("$FreeBSD$");
#endif
ENTRY(bzero)
movq %rsi,%rdx
cld /* set fill direction forward */
xorq %rax,%rax /* set fill data to 0 */
@ -22,23 +20,23 @@ ENTRY(bzero)
* of aligning to word boundries, etc. So we jump to a plain
* unaligned set.
*/
cmpq $16,%rdx
cmpq $16,%rsi
jb L1
movq %rdi,%rcx /* compute misalignment */
negq %rcx
andq $7,%rcx
subq %rcx,%rdx
subq %rcx,%rsi
rep /* zero until word aligned */
stosb
movq %rdx,%rcx /* zero by words */
movq %rsi,%rcx /* zero by words */
shrq $3,%rcx
andq $7,%rdx
andq $7,%rsi
rep
stosq
L1: movq %rdx,%rcx /* zero remainder by bytes */
L1: movq %rsi,%rcx /* zero remainder by bytes */
rep
stosb