3c8fdae78c
When shifting the low-parts of signed numbers, a logical shift should be used to avoid sign-extending a bit which isn't a sign bit. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
46 lines
857 B
ArmAsm
46 lines
857 B
ArmAsm
/*
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* linux/arch/arm/lib/muldi3.S
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*
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* Author: Nicolas Pitre
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* Created: Oct 19, 2005
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* Copyright: Monta Vista Software, Inc.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/linkage.h>
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#ifdef __ARMEB__
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#define xh r0
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#define xl r1
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#define yh r2
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#define yl r3
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#else
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#define xl r0
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#define xh r1
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#define yl r2
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#define yh r3
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#endif
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ENTRY(__muldi3)
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ENTRY(__aeabi_lmul)
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mul xh, yl, xh
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mla xh, xl, yh, xh
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mov ip, xl, lsr #16
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mov yh, yl, lsr #16
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bic xl, xl, ip, lsl #16
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bic yl, yl, yh, lsl #16
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mla xh, yh, ip, xh
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mul yh, xl, yh
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mul xl, yl, xl
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mul ip, yl, ip
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adds xl, xl, yh, lsl #16
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adc xh, xh, yh, lsr #16
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adds xl, xl, ip, lsl #16
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adc xh, xh, ip, lsr #16
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mov pc, lr
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