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linux_old1/arch/arm/lib/muldi3.S

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[ARM] 3049/1: More optimized libgcc functions Patch from Nicolas Pitre This patch gets rid of the last C implementations of needed libgcc functions for the kernel, replacing them with optimized assembly versions. Those functions are: __ashldi3 __ashrdi3 __lshrdi3 __muldi3 __ucmpdi2 The first 3 were lifted from gcc, the other two were written from scratch. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-31 07:08:03 +08:00
/*
* linux/arch/arm/lib/muldi3.S
*
* Author: Nicolas Pitre
* Created: Oct 19, 2005
* Copyright: Monta Vista Software, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
#ifdef __ARMEB__
#define xh r0
#define xl r1
#define yh r2
#define yl r3
#else
#define xl r0
#define xh r1
#define yl r2
#define yh r3
#endif
ENTRY(__muldi3)
[ARM] 3104/1: ARM EABI: new helper function names Patch from Nicolas Pitre The ARM EABI defines new names for GCC helper functions. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-15 00:18:29 +08:00
ENTRY(__aeabi_lmul)
[ARM] 3049/1: More optimized libgcc functions Patch from Nicolas Pitre This patch gets rid of the last C implementations of needed libgcc functions for the kernel, replacing them with optimized assembly versions. Those functions are: __ashldi3 __ashrdi3 __lshrdi3 __muldi3 __ucmpdi2 The first 3 were lifted from gcc, the other two were written from scratch. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-31 07:08:03 +08:00
mul xh, yl, xh
mla xh, xl, yh, xh
[ARM] Fix muldi3.S 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>
2006-03-09 01:25:33 +08:00
mov ip, xl, lsr #16
mov yh, yl, lsr #16
[ARM] 3049/1: More optimized libgcc functions Patch from Nicolas Pitre This patch gets rid of the last C implementations of needed libgcc functions for the kernel, replacing them with optimized assembly versions. Those functions are: __ashldi3 __ashrdi3 __lshrdi3 __muldi3 __ucmpdi2 The first 3 were lifted from gcc, the other two were written from scratch. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-31 07:08:03 +08:00
bic xl, xl, ip, lsl #16
bic yl, yl, yh, lsl #16
mla xh, yh, ip, xh
mul yh, xl, yh
mul xl, yl, xl
mul ip, yl, ip
adds xl, xl, yh, lsl #16
adc xh, xh, yh, lsr #16
adds xl, xl, ip, lsl #16
adc xh, xh, ip, lsr #16
mov pc, lr