56 lines
1 KiB
ArmAsm
56 lines
1 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0 */
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/*
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* arch/alpha/lib/strcat.S
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* Contributed by Richard Henderson (rth@tamu.edu)
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*
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* Append a null-terminated string from SRC to DST.
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*/
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#include <asm/export.h>
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.text
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.align 3
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.globl strcat
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.ent strcat
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strcat:
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.frame $30, 0, $26
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.prologue 0
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mov $16, $0 # set up return value
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/* Find the end of the string. */
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ldq_u $1, 0($16) # load first quadword (a0 may be misaligned)
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lda $2, -1
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insqh $2, $16, $2
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andnot $16, 7, $16
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or $2, $1, $1
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cmpbge $31, $1, $2 # bits set iff byte == 0
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bne $2, $found
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$loop: ldq $1, 8($16)
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addq $16, 8, $16
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cmpbge $31, $1, $2
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beq $2, $loop
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$found: negq $2, $3 # clear all but least set bit
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and $2, $3, $2
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and $2, 0xf0, $3 # binary search for that set bit
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and $2, 0xcc, $4
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and $2, 0xaa, $5
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cmovne $3, 4, $3
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cmovne $4, 2, $4
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cmovne $5, 1, $5
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addq $3, $4, $3
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addq $16, $5, $16
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addq $16, $3, $16
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/* Now do the append. */
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mov $26, $23
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br __stxcpy
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.end strcat
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EXPORT_SYMBOL(strcat);
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