target/riscv/m128_helper.c

   1 /*
   2  * RISC-V Emulation Helpers for QEMU.
   3  *
   4  * Copyright (c) 2016-2017 Sagar Karandikar, sagark@eecs.berkeley.edu
   5  * Copyright (c) 2017-2018 SiFive, Inc.
   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 "cpu.h"
  22 #include "exec/exec-all.h"
  23 #include "exec/helper-proto.h"
  24
  25 target_ulong HELPER(divu_i128)(CPURISCVState *env,
  26                                target_ulong ul, target_ulong uh,
  27                                target_ulong vl, target_ulong vh)
  28 {
  29     target_ulong ql, qh;
  30     Int128 q;
  31
  32     if (vl == 0 && vh == 0) { /* Handle special behavior on div by zero */
  33         ql = ~0x0;
  34         qh = ~0x0;
  35     } else {
  36         q = int128_divu(int128_make128(ul, uh), int128_make128(vl, vh));
  37         ql = int128_getlo(q);
  38         qh = int128_gethi(q);
  39     }
  40
  41     env->retxh = qh;
  42     return ql;
  43 }
  44
  45 target_ulong HELPER(remu_i128)(CPURISCVState *env,
  46                                target_ulong ul, target_ulong uh,
  47                                target_ulong vl, target_ulong vh)
  48 {
  49     target_ulong rl, rh;
  50     Int128 r;
  51
  52     if (vl == 0 && vh == 0) {
  53         rl = ul;
  54         rh = uh;
  55     } else {
  56         r = int128_remu(int128_make128(ul, uh), int128_make128(vl, vh));
  57         rl = int128_getlo(r);
  58         rh = int128_gethi(r);
  59     }
  60
  61     env->retxh = rh;
  62     return rl;
  63 }
  64
  65 target_ulong HELPER(divs_i128)(CPURISCVState *env,
  66                                target_ulong ul, target_ulong uh,
  67                                target_ulong vl, target_ulong vh)
  68 {
  69     target_ulong qh, ql;
  70     Int128 q;
  71
  72     if (vl == 0 && vh == 0) { /* Div by zero check */
  73         ql = ~0x0;
  74         qh = ~0x0;
  75     } else if (uh == (1ULL << (TARGET_LONG_BITS - 1)) && ul == 0 &&
  76                vh == ~0x0 && vl == ~0x0) {
  77         /* Signed div overflow check (-2**127 / -1) */
  78         ql = ul;
  79         qh = uh;
  80     } else {
  81         q = int128_divs(int128_make128(ul, uh), int128_make128(vl, vh));
  82         ql = int128_getlo(q);
  83         qh = int128_gethi(q);
  84     }
  85
  86     env->retxh = qh;
  87     return ql;
  88 }
  89
  90 target_ulong HELPER(rems_i128)(CPURISCVState *env,
  91                                target_ulong ul, target_ulong uh,
  92                                target_ulong vl, target_ulong vh)
  93 {
  94     target_ulong rh, rl;
  95     Int128 r;
  96
  97     if (vl == 0 && vh == 0) {
  98         rl = ul;
  99         rh = uh;
 100     } else {
 101         r = int128_rems(int128_make128(ul, uh), int128_make128(vl, vh));
 102         rl = int128_getlo(r);
 103         rh = int128_gethi(r);
 104     }
 105
 106     env->retxh = rh;
 107     return rl;
 108 }