Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/* Copyright 2002 Andi Kleen */

#include <linux/linkage.h>
#include <asm/dwarf2.h>
#include <asm/cpufeature.h>

/*
 * memcpy - Copy a memory block.
 *
 * Input:       
 * rdi destination
 * rsi source
 * rdx count
 * 
 * Output:
 * rax original destination
 */     

        ALIGN
memcpy_c:
        CFI_STARTPROC
        movq %rdi,%rax
        movl %edx,%ecx
        shrl $3,%ecx
        andl $7,%edx
        rep movsq
        movl %edx,%ecx
        rep movsb
        ret
        CFI_ENDPROC
ENDPROC(memcpy_c)

ENTRY(__memcpy)
ENTRY(memcpy)
        CFI_STARTPROC
        pushq %rbx
        CFI_ADJUST_CFA_OFFSET 8
        CFI_REL_OFFSET rbx, 0
        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
        CFI_ADJUST_CFA_OFFSET -8
        CFI_RESTORE rbx
        ret
.Lfinal:
        CFI_ENDPROC
ENDPROC(memcpy)
ENDPROC(__memcpy)

        /* Some CPUs run faster using the string copy instructions.
           It is also a lot simpler. Use this when possible */

        .section .altinstr_replacement,"ax"
1:      .byte 0xeb                              /* jmp <disp8> */
        .byte (memcpy_c - memcpy) - (2f - 1b)   /* offset */
2:
        .previous
        .section .altinstructions,"a"
        .align 8
        .quad memcpy
        .quad 1b
        .byte X86_FEATURE_REP_GOOD
        /* Replace only beginning, memcpy is used to apply alternatives, so it
         * is silly to overwrite itself with nops - reboot is only outcome... */
        .byte 2b - 1b
        .byte 2b - 1b
        .previous