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 "qemu/main-loop.h"
  23 #include "exec/exec-all.h"
  24 #include "exec/helper-proto.h"
  25
  26 target_ulong HELPER(divu_i128)(CPURISCVState *env,
  27                                target_ulong ul, target_ulong uh,
  28                                target_ulong vl, target_ulong vh)
  29 {
  30     target_ulong ql, qh;
  31     Int128 q;
  32
  33     if (vl == 0 && vh == 0) { /* Handle special behavior on div by zero */
  34         ql = ~0x0;
  35         qh = ~0x0;
  36     } else {
  37         q = int128_divu(int128_make128(ul, uh), int128_make128(vl, vh));
  38         ql = int128_getlo(q);
  39         qh = int128_gethi(q);
  40     }
  41
  42     env->retxh = qh;
  43     return ql;
  44 }
  45
  46 target_ulong HELPER(remu_i128)(CPURISCVState *env,
  47                                target_ulong ul, target_ulong uh,
  48                                target_ulong vl, target_ulong vh)
  49 {
  50     target_ulong rl, rh;
  51     Int128 r;
  52
  53     if (vl == 0 && vh == 0) {
  54         rl = ul;
  55         rh = uh;
  56     } else {
  57         r = int128_remu(int128_make128(ul, uh), int128_make128(vl, vh));
  58         rl = int128_getlo(r);
  59         rh = int128_gethi(r);
  60     }
  61
  62     env->retxh = rh;
  63     return rl;
  64 }
  65
  66 target_ulong HELPER(divs_i128)(CPURISCVState *env,
  67                                target_ulong ul, target_ulong uh,
  68                                target_ulong vl, target_ulong vh)
  69 {
  70     target_ulong qh, ql;
  71     Int128 q;
  72
  73     if (vl == 0 && vh == 0) { /* Div by zero check */
  74         ql = ~0x0;
  75         qh = ~0x0;
  76     } else if (uh == (1ULL << (TARGET_LONG_BITS - 1)) && ul == 0 &&
  77                vh == ~0x0 && vl == ~0x0) {
  78         /* Signed div overflow check (-2**127 / -1) */
  79         ql = ul;
  80         qh = uh;
  81     } else {
  82         q = int128_divs(int128_make128(ul, uh), int128_make128(vl, vh));
  83         ql = int128_getlo(q);
  84         qh = int128_gethi(q);
  85     }
  86
  87     env->retxh = qh;
  88     return ql;
  89 }
  90
  91 target_ulong HELPER(rems_i128)(CPURISCVState *env,
  92                                target_ulong ul, target_ulong uh,
  93                                target_ulong vl, target_ulong vh)
  94 {
  95     target_ulong rh, rl;
  96     Int128 r;
  97
  98     if (vl == 0 && vh == 0) {
  99         rl = ul;
 100         rh = uh;
 101     } else {
 102         r = int128_rems(int128_make128(ul, uh), int128_make128(vl, vh));
 103         rl = int128_getlo(r);
 104         rh = int128_gethi(r);
 105     }
 106
 107     env->retxh = rh;
 108     return rl;
 109 }