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/* Copyright 2002 Andi Kleen, SuSE Labs */

/*
 * ISO C memset - set a memory block to a byte value.
 *      
 * rdi   destination
 * rsi   value (char) 
 * rdx   count (bytes) 
 * 
 * rax   original destination
 */     
        .globl __memset
        .globl memset
        .p2align 4
memset: 
__memset:
        movq %rdi,%r10
        movq %rdx,%r11

        /* expand byte value  */
        movzbl %sil,%ecx
        movabs $0x0101010101010101,%rax
        mul    %rcx             /* with rax, clobbers rdx */

        /* align dst */
        movl  %edi,%r9d
        andl  $7,%r9d   
        jnz  .Lbad_alignment
.Lafter_bad_alignment:

        movl %r11d,%ecx
        shrl $6,%ecx
        jz       .Lhandle_tail

        .p2align 4
.Lloop_64:      
        decl   %ecx
        movq  %rax,(%rdi) 
        movq  %rax,8(%rdi) 
        movq  %rax,16(%rdi) 
        movq  %rax,24(%rdi) 
        movq  %rax,32(%rdi) 
        movq  %rax,40(%rdi) 
        movq  %rax,48(%rdi) 
        movq  %rax,56(%rdi) 
        leaq  64(%rdi),%rdi
        jnz    .Lloop_64

        /* Handle tail in loops. The loops should be faster than hard
           to predict jump tables. */ 
        .p2align 4         
.Lhandle_tail:
        movl    %r11d,%ecx
        andl    $63&(~7),%ecx
        jz              .Lhandle_7
        shrl    $3,%ecx
        .p2align 4
.Lloop_8:
        decl   %ecx
        movq  %rax,(%rdi)
        leaq  8(%rdi),%rdi
        jnz    .Lloop_8

.Lhandle_7:
        movl    %r11d,%ecx
        andl    $7,%ecx
        jz      .Lende
        .p2align 4
.Lloop_1:
        decl    %ecx
        movb    %al,(%rdi)
        leaq    1(%rdi),%rdi
        jnz     .Lloop_1
        
.Lende: 
        movq    %r10,%rax
        ret

.Lbad_alignment:
        cmpq $7,%r11
        jbe     .Lhandle_7
        movq %rax,(%rdi)        /* unaligned store */
        movq $8,%r8
        subq %r9,%r8 
        addq %r8,%rdi
        subq %r8,%r11
        jmp .Lafter_bad_alignment