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annotate target-utils/libc/strlen.S @ 620:dd162a4cb9fa

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CHANGES: objective performance comparison instead of blind patch
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 27 Feb 2020 01:21:58 +0000
parents 3670e7768ab6
children
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95
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
parents:
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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>
parents:
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5 mov r1, r0
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
parents:
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6 1: ldrb r2, [r0], #1
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
parents:
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7 cmn r2, #0
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
parents:
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8 bne 1b
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
parents:
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9 sbc r0, r0, r1
3670e7768ab6 target-utils/libc: strlen optimized assembly implementation added
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 bx lr