| /* |
| * 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. |
| * |
| * SPDX-License-Identifier: GPL-2.0+ |
| */ |
| |
| #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 __ashldi3 |
| __ashldi3: |
| subfic r6,r5,32 |
| slw r3,r3,r5 # MSW = count > 31 ? 0 : MSW << count |
| addi r7,r5,32 # could be xori, or addi with -32 |
| srw r6,r4,r6 # t1 = count > 31 ? 0 : LSW >> (32-count) |
| slw r7,r4,r7 # t2 = count < 32 ? 0 : LSW << (count-32) |
| or r3,r3,r6 # MSW |= t1 |
| slw r4,r4,r5 # LSW = LSW << count |
| or r3,r3,r7 # MSW |= t2 |
| blr |
