1 /* 2 * RISC-V Bitmanip Extension Helpers for QEMU. 3 * 4 * Copyright (c) 2020 Kito Cheng, kito.cheng@sifive.com 5 * Copyright (c) 2020 Frank Chang, frank.chang@sifive.com 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms and conditions of the GNU General Public License, 9 * version 2 or later, as published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 14 * more details. 15 * 16 * You should have received a copy of the GNU General Public License along with 17 * this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #include "qemu/osdep.h" 21 #include "qemu/host-utils.h" 22 #include "exec/exec-all.h" 23 #include "exec/helper-proto.h" 24 #include "tcg/tcg.h" 25 26 static const uint64_t adjacent_masks[] = { 27 dup_const(MO_8, 0x55), 28 dup_const(MO_8, 0x33), 29 dup_const(MO_8, 0x0f), 30 dup_const(MO_16, 0xff), 31 dup_const(MO_32, 0xffff), 32 UINT32_MAX 33 }; 34 35 static inline target_ulong do_swap(target_ulong x, uint64_t mask, int shift) 36 { 37 return ((x & mask) << shift) | ((x & ~mask) >> shift); 38 } 39 40 static target_ulong do_grev(target_ulong rs1, 41 target_ulong rs2, 42 int bits) 43 { 44 target_ulong x = rs1; 45 int i, shift; 46 47 for (i = 0, shift = 1; shift < bits; i++, shift <<= 1) { 48 if (rs2 & shift) { 49 x = do_swap(x, adjacent_masks[i], shift); 50 } 51 } 52 53 return x; 54 } 55 56 target_ulong HELPER(grev)(target_ulong rs1, target_ulong rs2) 57 { 58 return do_grev(rs1, rs2, TARGET_LONG_BITS); 59 } 60 61 target_ulong HELPER(grevw)(target_ulong rs1, target_ulong rs2) 62 { 63 return do_grev(rs1, rs2, 32); 64 } 65