FreeCalypso > hg > freecalypso-tools

annotate target-utils/libc/strlen.S @ 561:392525355ee7

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loadtools/scripts: gtm900.config renamed to gen4.config It turns out that a GTM900 variant exists with 8 MiB flash, thus -h gen8 needs to be used for GTM900 modules as the general case, and the old -h gtm900 config is best renamed to -h gen4, although not currently official for any actual target.
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 30 Jan 2020 07:10:20 +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
Mychaela Falconia <falcon@freecalypso.org>
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2 .code 32
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
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3 .globl strlen
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
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4 strlen:
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
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5 mov r1, r0
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
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6 1: ldrb r2, [r0], #1
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
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7 cmn r2, #0
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
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8 bne 1b
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
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9 sbc r0, r0, r1
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
parents:
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10 bx lr