37 lines
820 B
ArmAsm
37 lines
820 B
ArmAsm
#
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/*
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* VideoCore IV support library for the ACK
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* © 2013 David Given
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* This file is redistributable under the terms of the 3-clause BSD license.
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* See the file 'Copying' in the root of the distribution for the full text.
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*/
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#include "videocore.h"
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.define .csa
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.sect .data
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.csa:
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! on entry:
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! r0 = un-fixed-up descriptor
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! r1 = value
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add r0, gp
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ld r2, 4 (r0) ! check lower bound
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b.lo r1, r2, default ! jump to default if r1 < r2
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sub r1, r2 ! adjust value to be 0-based
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ld r2, 8 (r0) ! check upper bound
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b.hi r1, r2, default ! jump to default if r1 > r2
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add r1, #3
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go:
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ld r1, (r0, r1) ! load destination address
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add r1, gp
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b r1 ! ...and go
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default:
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mov r1, #0 ! index of default value
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b go
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