b6cbf7203b
This patch imports the unmodified current version of NetBSD libc. The NetBSD includes are in /nbsd_include, while the libc code itself is split between lib/nbsd_libc and common/lib/libc.
165 lines
2.6 KiB
ArmAsm
165 lines
2.6 KiB
ArmAsm
/*
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* Written by J.T. Conklin <jtc@acorntoolworks.com>
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* Public domain.
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*/
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#include <machine/asm.h>
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#if defined(LIBC_SCCS)
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RCSID("$NetBSD: strcat.S,v 1.1 2005/12/20 19:28:51 christos Exp $")
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#endif
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ENTRY(strcat)
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movq %rdi,%rax
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movabsq $0x0101010101010101,%r8
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movabsq $0x8080808080808080,%r9
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/*
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* Align destination to word boundary.
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* Consider unrolling loop?
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*/
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.Lscan:
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.Lscan_align:
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testb $7,%dil
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je .Lscan_aligned
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cmpb $0,(%rdi)
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je .Lcopy
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incq %rdi
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jmp .Lscan_align
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_ALIGN_TEXT
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.Lscan_aligned:
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.Lscan_loop:
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movq (%rdi),%rdx
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addq $8,%rdi
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subq %r8,%rdx
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testq %r9,%rdx
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je .Lscan_loop
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/*
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* In rare cases, the above loop may exit prematurely. We must
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* return to the loop if none of the bytes in the word equal 0.
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*/
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cmpb $0,-8(%rdi) /* 1st byte == 0? */
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jne 1f
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subq $8,%rdi
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jmp .Lcopy
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1: cmpb $0,-7(%rdi) /* 2nd byte == 0? */
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jne 1f
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subq $7,%rdi
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jmp .Lcopy
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1: cmpb $0,-6(%rdi) /* 3rd byte == 0? */
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jne 1f
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subq $6,%rdi
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jmp .Lcopy
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1: cmpb $0,-5(%rdi) /* 4th byte == 0? */
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jne 1f
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subq $5,%rdi
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jmp .Lcopy
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1: cmpb $0,-4(%rdi) /* 5th byte == 0? */
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jne 1f
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subq $4,%rdi
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jmp .Lcopy
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1: cmpb $0,-3(%rdi) /* 6th byte == 0? */
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jne 1f
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subq $3,%rdi
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jmp .Lcopy
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1: cmpb $0,-2(%rdi) /* 7th byte == 0? */
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jne 1f
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subq $2,%rdi
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jmp .Lcopy
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1: cmpb $0,-1(%rdi) /* 8th byte == 0? */
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jne .Lscan_loop
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subq $1,%rdi
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/*
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* Align source to a word boundary.
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* Consider unrolling loop?
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*/
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.Lcopy:
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.Lcopy_align:
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testb $7,%sil
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je .Lcopy_aligned
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movb (%rsi),%dl
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incq %rsi
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movb %dl,(%rdi)
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incq %rdi
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testb %dl,%dl
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jne .Lcopy_align
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ret
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_ALIGN_TEXT
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.Lcopy_loop:
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movq %rdx,(%rdi)
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addq $8,%rdi
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.Lcopy_aligned:
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movq (%rsi),%rdx
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movq %rdx,%rcx
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addq $8,%rsi
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subq %r8,%rcx
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testq %r9,%rcx
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je .Lcopy_loop
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/*
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* In rare cases, the above loop may exit prematurely. We must
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* return to the loop if none of the bytes in the word equal 0.
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*/
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movb %dl,(%rdi)
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incq %rdi
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testb %dl,%dl /* 1st byte == 0? */
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je .Ldone
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shrq $8,%rdx
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movb %dl,(%rdi)
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incq %rdi
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testb %dl,%dl /* 2nd byte == 0? */
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je .Ldone
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shrq $8,%rdx
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movb %dl,(%rdi)
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incq %rdi
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testb %dl,%dl /* 3rd byte == 0? */
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je .Ldone
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shrq $8,%rdx
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movb %dl,(%rdi)
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incq %rdi
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testb %dl,%dl /* 4th byte == 0? */
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je .Ldone
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shrq $8,%rdx
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movb %dl,(%rdi)
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incq %rdi
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testb %dl,%dl /* 5th byte == 0? */
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je .Ldone
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shrq $8,%rdx
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movb %dl,(%rdi)
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incq %rdi
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testb %dl,%dl /* 6th byte == 0? */
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je .Ldone
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shrq $8,%rdx
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movb %dl,(%rdi)
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incq %rdi
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testb %dl,%dl /* 7th byte == 0? */
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je .Ldone
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shrq $8,%rdx
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movb %dl,(%rdi)
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incq %rdi
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testb %dl,%dl /* 8th byte == 0? */
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jne .Lcopy_aligned
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.Ldone:
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ret
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