| /* Runtime ABI for the ARM Cortex-M0 |
| * lmul.S: 64 bit multiplication |
| * |
| * Copyright (c) 2013 Jörg Mische <bobbl@gmx.de> |
| * |
| * Permission to use, copy, modify, and/or distribute this software for any |
| * purpose with or without fee is hereby granted, provided that the above |
| * copyright notice and this permission notice appear in all copies. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES |
| * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR |
| * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT |
| * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| */ |
| |
| |
| |
| .syntax unified |
| .text |
| .thumb |
| .cpu cortex-m0 |
| |
| |
| |
| @ long long __aeabi_lmul(long long r1:r0, long long r3:r2) |
| @ |
| @ Multiply r1:r0 and r3:r2 and return the product in r1:r0 |
| @ Can also be used for unsigned long product |
| @ |
| .thumb_func |
| .section .text.__aeabi_lmul |
| .global __aeabi_lmul |
| __aeabi_lmul: |
| |
| push {r4, lr} |
| muls r1, r2 |
| muls r3, r0 |
| adds r1, r3 |
| |
| lsrs r3, r0, #16 |
| lsrs r4, r2, #16 |
| muls r3, r4 |
| adds r1, r3 |
| |
| lsrs r3, r0, #16 |
| uxth r0, r0 |
| uxth r2, r2 |
| muls r3, r2 |
| muls r4, r0 |
| muls r0, r2 |
| |
| movs r2, #0 |
| adds r3, r4 |
| adcs r2, r2 |
| lsls r2, #16 |
| adds r1, r2 |
| |
| lsls r2, r3, #16 |
| lsrs r3, #16 |
| adds r0, r2 |
| adcs r1, r3 |
| pop {r4, pc} |
