d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Remove redundand CLD instructions.

Browse Source 
We already clear %RFLAGS.DF on the kernel entry due to the compiler's
ABI requirements.

Suggested by:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
This commit is contained in:
Konstantin Belousov 2018-01-11 13:22:13 +00:00
parent 4975c202ac
commit 6da5c56ae5
2 changed files with 0 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
sys/amd64/amd64/support.S
View File

@ -50,7 +50,6 @@ ENTRY(bzero)
movq %rsi,%rcx movq %rsi,%rcx
xorl %eax,%eax xorl %eax,%eax
shrq $3,%rcx shrq $3,%rcx
cld
rep rep
stosq stosq
movq %rsi,%rcx movq %rsi,%rcx
@ -100,7 +99,6 @@ ENTRY(bcmp)
PUSH_FRAME_POINTER PUSH_FRAME_POINTER
movq %rdx,%rcx movq %rdx,%rcx
shrq $3,%rcx shrq $3,%rcx
cld /* compare forwards */
repe repe
cmpsq cmpsq
jne 1f jne 1f
@ -132,7 +130,6 @@ ENTRY(bcopy)
jb 1f jb 1f
shrq $3,%rcx /* copy by 64-bit words */ shrq $3,%rcx /* copy by 64-bit words */
cld /* nope, copy forwards */
rep rep
movsq movsq
movq %rdx,%rcx movq %rdx,%rcx
@ -171,7 +168,6 @@ ENTRY(memcpy)
movq %rdi,%rax movq %rdi,%rax
movq %rdx,%rcx movq %rdx,%rcx
shrq $3,%rcx /* copy by 64-bit words */ shrq $3,%rcx /* copy by 64-bit words */
cld /* copy forwards */
rep rep
movsq movsq
movq %rdx,%rcx movq %rdx,%rcx
@ -218,7 +214,6 @@ ENTRY(fillw)
movq %rdi,%rax movq %rdi,%rax
movq %rsi,%rdi movq %rsi,%rdi
movq %rdx,%rcx movq %rdx,%rcx
cld
rep rep
stosw stosw
POP_FRAME_POINTER POP_FRAME_POINTER
@ -274,7 +269,6 @@ ENTRY(copyout)
movq %rdx,%rcx movq %rdx,%rcx
shrq $3,%rcx shrq $3,%rcx
cld
rep rep
movsq movsq
movb %dl,%cl movb %dl,%cl
@ -323,7 +317,6 @@ ENTRY(copyin)
movq %rdx,%rcx movq %rdx,%rcx
movb %cl,%al movb %cl,%al
shrq $3,%rcx /* copy longword-wise */ shrq $3,%rcx /* copy longword-wise */
cld
rep rep
movsq movsq
movb %al,%cl movb %al,%cl
@ -620,7 +613,6 @@ ENTRY(copyinstr)
movq %rax,%r8 movq %rax,%r8
1: 1:
incq %rdx incq %rdx
cld
2: 2:
decq %rdx decq %rdx
@ -671,7 +663,6 @@ ENTRY(copystr)
xchgq %rdi,%rsi xchgq %rdi,%rsi
incq %rdx incq %rdx
cld
1: 1:
decq %rdx decq %rdx
jz 4f jz 4f

11
sys/i386/i386/support.s
View File

@ -50,7 +50,6 @@ ENTRY(bzero)
movl 12(%esp),%ecx movl 12(%esp),%ecx
xorl %eax,%eax xorl %eax,%eax
shrl $2,%ecx shrl $2,%ecx
cld
rep rep
stosl stosl
movl 12(%esp),%ecx movl 12(%esp),%ecx
@ -90,7 +89,6 @@ ENTRY(i686_pagezero)
movl 12(%esp),%edi movl 12(%esp),%edi
movl $1024,%ecx movl $1024,%ecx
cld
ALIGN_TEXT ALIGN_TEXT
1: 1:
@ -141,7 +139,6 @@ ENTRY(fillw)
movl 8(%esp),%eax movl 8(%esp),%eax
movl 12(%esp),%edi movl 12(%esp),%edi
movl 16(%esp),%ecx movl 16(%esp),%ecx
cld
rep rep
stosw stosw
popl %edi popl %edi
@ -158,7 +155,6 @@ ENTRY(bcopyb)
subl %esi,%eax subl %esi,%eax
cmpl %ecx,%eax /* overlapping && src < dst? */ cmpl %ecx,%eax /* overlapping && src < dst? */
jb 1f jb 1f
cld /* nope, copy forwards */
rep rep
movsb movsb
popl %edi popl %edi
@ -199,7 +195,6 @@ ENTRY(bcopy)
jb 1f jb 1f
shrl $2,%ecx /* copy by 32-bit words */ shrl $2,%ecx /* copy by 32-bit words */
cld /* nope, copy forwards */
rep rep
movsl movsl
movl 16(%ebp),%ecx movl 16(%ebp),%ecx
@ -245,7 +240,6 @@ ENTRY(memcpy)
movl 20(%esp),%ecx movl 20(%esp),%ecx
movl %edi,%eax movl %edi,%eax
shrl $2,%ecx /* copy by 32-bit words */ shrl $2,%ecx /* copy by 32-bit words */
cld /* nope, copy forwards */
rep rep
movsl movsl
movl 20(%esp),%ecx movl 20(%esp),%ecx
@ -314,7 +308,6 @@ ENTRY(copyout)
movl %ebx,%ecx movl %ebx,%ecx
shrl $2,%ecx shrl $2,%ecx
cld
rep rep
movsl movsl
movb %bl,%cl movb %bl,%cl
@ -365,7 +358,6 @@ ENTRY(copyin)
movb %cl,%al movb %cl,%al
shrl $2,%ecx /* copy longword-wise */ shrl $2,%ecx /* copy longword-wise */
cld
rep rep
movsl movsl
movb %al,%cl movb %al,%cl
@ -582,7 +574,6 @@ ENTRY(copyinstr)
movl %eax,20(%esp) movl %eax,20(%esp)
1: 1:
incl %edx incl %edx
cld
2: 2:
decl %edx decl %edx
@ -635,7 +626,6 @@ ENTRY(copystr)
movl 16(%esp),%edi /* %edi = to */ movl 16(%esp),%edi /* %edi = to */
movl 20(%esp),%edx /* %edx = maxlen */ movl 20(%esp),%edx /* %edx = maxlen */
incl %edx incl %edx
cld
1: 1:
decl %edx decl %edx
jz 4f jz 4f
@ -675,7 +665,6 @@ ENTRY(bcmp)
movl %edx,%ecx movl %edx,%ecx
shrl $2,%ecx shrl $2,%ecx
cld /* compare forwards */
repe repe
cmpsl cmpsl
jne 1f jne 1f