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Diffstat (limited to 'arch/x86_64/lib/memcpy.S')
-rw-r--r--arch/x86_64/lib/memcpy.S93
1 files changed, 2 insertions, 91 deletions
diff --git a/arch/x86_64/lib/memcpy.S b/arch/x86_64/lib/memcpy.S
index c6c46494fef..92dd8054460 100644
--- a/arch/x86_64/lib/memcpy.S
+++ b/arch/x86_64/lib/memcpy.S
@@ -11,6 +11,8 @@
*
* Output:
* rax original destination
+ *
+ * TODO: check best memcpy for PSC
*/
.globl __memcpy
@@ -18,95 +20,6 @@
.p2align 4
__memcpy:
memcpy:
- pushq %rbx
- movq %rdi,%rax
-
- movl %edx,%ecx
- shrl $6,%ecx
- jz .Lhandle_tail
-
- .p2align 4
-.Lloop_64:
- decl %ecx
-
- movq (%rsi),%r11
- movq 8(%rsi),%r8
-
- movq %r11,(%rdi)
- movq %r8,1*8(%rdi)
-
- movq 2*8(%rsi),%r9
- movq 3*8(%rsi),%r10
-
- movq %r9,2*8(%rdi)
- movq %r10,3*8(%rdi)
-
- movq 4*8(%rsi),%r11
- movq 5*8(%rsi),%r8
-
- movq %r11,4*8(%rdi)
- movq %r8,5*8(%rdi)
-
- movq 6*8(%rsi),%r9
- movq 7*8(%rsi),%r10
-
- movq %r9,6*8(%rdi)
- movq %r10,7*8(%rdi)
-
- leaq 64(%rsi),%rsi
- leaq 64(%rdi),%rdi
- jnz .Lloop_64
-
-.Lhandle_tail:
- movl %edx,%ecx
- andl $63,%ecx
- shrl $3,%ecx
- jz .Lhandle_7
- .p2align 4
-.Lloop_8:
- decl %ecx
- movq (%rsi),%r8
- movq %r8,(%rdi)
- leaq 8(%rdi),%rdi
- leaq 8(%rsi),%rsi
- jnz .Lloop_8
-
-.Lhandle_7:
- movl %edx,%ecx
- andl $7,%ecx
- jz .Lende
- .p2align 4
-.Lloop_1:
- movb (%rsi),%r8b
- movb %r8b,(%rdi)
- incq %rdi
- incq %rsi
- decl %ecx
- jnz .Lloop_1
-
-.Lende:
- popq %rbx
- ret
-.Lfinal:
-
- /* C stepping K8 run faster using the string copy instructions.
- It is also a lot simpler. Use this when possible */
-
- .section .altinstructions,"a"
- .align 8
- .quad memcpy
- .quad memcpy_c
- .byte X86_FEATURE_K8_C
- .byte .Lfinal-memcpy
- .byte memcpy_c_end-memcpy_c
- .previous
-
- .section .altinstr_replacement,"ax"
- /* rdi destination
- * rsi source
- * rdx count
- */
-memcpy_c:
movq %rdi,%rax
movl %edx,%ecx
shrl $3,%ecx
@@ -117,5 +30,3 @@ memcpy_c:
rep
movsb
ret
-memcpy_c_end:
- .previous