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  • Committer: Bazaar Package Importer
  • Author(s): Hakan Ardo
  • Date: 2002-04-15 14:53:38 UTC
  • Revision ID: james.westby@ubuntu.com-20020415145338-c8hi0tn5bx74w7o3
Tags: upstream-20020203
Import upstream version 20020203

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libc/string/strlen.S
 
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#include "macros.inc"
 
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#define src_hi r25
 
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#define src_lo r24
 
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; size_t strlen(const char *src)
 
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; 10 words, (14 + strlen(src) * 5) cycles
 
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        .text
 
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        .global _U(strlen)
 
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        .type   _U(strlen), @function
 
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_U(strlen):
 
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        LOAD_Z(src_lo, src_hi)
 
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.strlen_loop:
 
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        ld      __tmp_reg__, Z+
 
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        tst     __tmp_reg__
 
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        brne    .strlen_loop
 
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; Z points one character past the terminating NUL
 
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; return Z - 1 - src = (-1 - src) + Z = ~src + Z
 
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        com     src_lo
 
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        com     src_hi
 
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        add     src_lo, ZL
 
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        adc     src_hi, ZH
 
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        ret
 
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.strlen_end:
 
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        .size   _U(strlen), .strlen_end - _U(strlen)
 
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