+++ /dev/null
-/* Copyright 2002 Andi Kleen */
-
- #include <arch/cpufeature.h>
-/*
- * memcpy - Copy a memory block.
- *
- * Input:
- * rdi destination
- * rsi source
- * rdx count
- *
- * Output:
- * rax original destination
- */
-
- .globl __memcpy
- .globl memcpy
- .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:
-
- /* Some CPUs 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_REP_GOOD
- .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
- andl $7,%edx
- rep
- movsq
- movl %edx,%ecx
- rep
- movsb
- ret
-memcpy_c_end:
- .previous
