Last change
on this file since 444 was
444,
checked in by satin@…, 6 years ago
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add newlib,libalmos-mkh, restructure shared_syscalls.h and mini-libc
|
File size:
650 bytes
|
Rev | Line | |
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[444] | 1 | /* |
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| 2 | * C library strlen routine |
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| 3 | * |
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| 4 | * This routine has been optimized for the CPU32+. |
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| 5 | * It should run on all 68k machines. |
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| 6 | * |
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| 7 | * W. Eric Norum |
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| 8 | * Saskatchewan Accelerator Laboratory |
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| 9 | * University of Saskatchewan |
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| 10 | * Saskatoon, Saskatchewan, CANADA |
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| 11 | * eric@skatter.usask.ca |
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| 12 | */ |
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| 13 | |
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| 14 | #include <string.h> |
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| 15 | |
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| 16 | /* |
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| 17 | * Test bytes using CPU32+ loop mode if possible. |
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| 18 | */ |
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| 19 | size_t |
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| 20 | strlen (const char *str) |
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| 21 | { |
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| 22 | unsigned int n = ~0; |
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| 23 | const char *cp = str; |
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| 24 | |
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| 25 | asm volatile ("1:\n" |
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| 26 | "\ttst.b (%0)+\n" |
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| 27 | #if defined(__mcpu32__) |
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| 28 | "\tdbeq %1,1b\n" |
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| 29 | #endif |
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| 30 | "\tbne.b 1b\n" : |
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| 31 | "=a" (cp), "=d" (n) : |
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| 32 | "0" (cp), "1" (n) : |
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| 33 | "cc"); |
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| 34 | return (cp - str) - 1; |
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| 35 | } |
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