diff options
| author | Nicolas Pitre <nico@cam.org> | 2005-10-31 02:08:03 +0300 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2005-10-31 02:08:03 +0300 |
| commit | f741a1aab5fd7892927208ca37eb86b9ea85784a (patch) | |
| tree | c4060ea9292f5e8f98e87ef354079bc900d81243 /arch/arm/lib/muldi3.S | |
| parent | cb7610d018235653c73ff1fea79b962c16317474 (diff) | |
| download | linux-f741a1aab5fd7892927208ca37eb86b9ea85784a.tar.xz | |
[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>
Diffstat (limited to 'arch/arm/lib/muldi3.S')
| -rw-r--r-- | arch/arm/lib/muldi3.S | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/arch/arm/lib/muldi3.S b/arch/arm/lib/muldi3.S new file mode 100644 index 000000000000..c7fbdf005319 --- /dev/null +++ b/arch/arm/lib/muldi3.S @@ -0,0 +1,44 @@ +/* + * 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) + + mul xh, yl, xh + mla xh, xl, yh, xh + mov ip, xl, asr #16 + mov yh, yl, asr #16 + 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 + |