annotate target-utils/libc/strlen.S @ 407:19e5a3e2f9c0

fcup-settime: moved time() retrieval a little closer to the output A fundamental problem with all simple time transfer tools is that there is always some delay between the time retrieval on the source system and that transmitted time being set on the destination, and the resulting time on the destination system is off by that delay amount. This delay cannot be fully eliminated when working in a simple environment like ours, but we should make our best effort to minimize it. In the present case, moving the atinterf_init() call before the time() retrieval should make a teensy-tiny improvement.
author Mychaela Falconia <falcon@freecalypso.org>
date Sat, 11 Aug 2018 21:52:17 +0000
parents 3670e7768ab6
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
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1 .text
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
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2 .code 32
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
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3 .globl strlen
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
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4 strlen:
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
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5 mov r1, r0
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
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6 1: ldrb r2, [r0], #1
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
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7 cmn r2, #0
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
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8 bne 1b
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
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9 sbc r0, r0, r1
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
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10 bx lr