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Diffstat (limited to 'roms/u-boot/arch/powerpc/lib/_ashrdi3.S')
| -rw-r--r-- | roms/u-boot/arch/powerpc/lib/_ashrdi3.S | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/roms/u-boot/arch/powerpc/lib/_ashrdi3.S b/roms/u-boot/arch/powerpc/lib/_ashrdi3.S new file mode 100644 index 000000000..728001696 --- /dev/null +++ b/roms/u-boot/arch/powerpc/lib/_ashrdi3.S @@ -0,0 +1,43 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * This code was copied from arch/powerpc/kernel/misc_32.S in the Linux + * kernel sources (commit 85e2efbb1db9a18d218006706d6e4fbeb0216213, also + * known as 2.6.38-rc5). The source file copyrights are as follows: + * + * (C) Copyright 1995-1996 Gary Thomas (gdt@linuxppc.org) + * + * Largely rewritten by Cort Dougan (cort@cs.nmt.edu) + * and Paul Mackerras. + */ + +#include <ppc_asm.tmpl> +#include <ppc_defs.h> +#include <config.h> + +/* + * Extended precision shifts. + * + * Updated to be valid for shift counts from 0 to 63 inclusive. + * -- Gabriel + * + * R3/R4 has 64 bit value + * R5 has shift count + * result in R3/R4 + * + * ashrdi3: arithmetic right shift (sign propagation) + * lshrdi3: logical right shift + * ashldi3: left shift + */ + .globl __ashrdi3 +__ashrdi3: + subfic r6,r5,32 + srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count + addi r7,r5,32 # could be xori, or addi with -32 + slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count) + rlwinm r8,r7,0,32 # t3 = (count < 32) ? 32 : 0 + sraw r7,r3,r7 # t2 = MSW >> (count-32) + or r4,r4,r6 # LSW |= t1 + slw r7,r7,r8 # t2 = (count < 32) ? 0 : t2 + sraw r3,r3,r5 # MSW = MSW >> count + or r4,r4,r7 # LSW |= t2 + blr |