qemu

FORK: QEMU emulator
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fpu_helper.c (5698B)


      1 /*
      2  * OpenRISC float helper routines
      3  *
      4  * Copyright (c) 2011-2012 Jia Liu <proljc@gmail.com>
      5  *                         Feng Gao <gf91597@gmail.com>
      6  *
      7  * This library is free software; you can redistribute it and/or
      8  * modify it under the terms of the GNU Lesser General Public
      9  * License as published by the Free Software Foundation; either
     10  * version 2.1 of the License, or (at your option) any later version.
     11  *
     12  * This library is distributed in the hope that it will be useful,
     13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
     14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     15  * Lesser General Public License for more details.
     16  *
     17  * You should have received a copy of the GNU Lesser General Public
     18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
     19  */
     20 
     21 #include "qemu/osdep.h"
     22 #include "cpu.h"
     23 #include "exec/helper-proto.h"
     24 #include "exception.h"
     25 #include "fpu/softfloat.h"
     26 
     27 static int ieee_ex_to_openrisc(int fexcp)
     28 {
     29     int ret = 0;
     30     if (fexcp & float_flag_invalid) {
     31         ret |= FPCSR_IVF;
     32     }
     33     if (fexcp & float_flag_overflow) {
     34         ret |= FPCSR_OVF;
     35     }
     36     if (fexcp & float_flag_underflow) {
     37         ret |= FPCSR_UNF;
     38     }
     39     if (fexcp & float_flag_divbyzero) {
     40         ret |= FPCSR_DZF;
     41     }
     42     if (fexcp & float_flag_inexact) {
     43         ret |= FPCSR_IXF;
     44     }
     45     return ret;
     46 }
     47 
     48 void HELPER(update_fpcsr)(CPUOpenRISCState *env)
     49 {
     50     int tmp = get_float_exception_flags(&env->fp_status);
     51 
     52     if (tmp) {
     53         set_float_exception_flags(0, &env->fp_status);
     54         tmp = ieee_ex_to_openrisc(tmp);
     55         if (tmp) {
     56             env->fpcsr |= tmp;
     57             if (env->fpcsr & FPCSR_FPEE) {
     58                 helper_exception(env, EXCP_FPE);
     59             }
     60         }
     61     }
     62 }
     63 
     64 void cpu_set_fpcsr(CPUOpenRISCState *env, uint32_t val)
     65 {
     66     static const int rm_to_sf[] = {
     67         float_round_nearest_even,
     68         float_round_to_zero,
     69         float_round_up,
     70         float_round_down
     71     };
     72 
     73     env->fpcsr = val & 0xfff;
     74     set_float_rounding_mode(rm_to_sf[extract32(val, 1, 2)], &env->fp_status);
     75 }
     76 
     77 uint64_t HELPER(itofd)(CPUOpenRISCState *env, uint64_t val)
     78 {
     79     return int64_to_float64(val, &env->fp_status);
     80 }
     81 
     82 uint32_t HELPER(itofs)(CPUOpenRISCState *env, uint32_t val)
     83 {
     84     return int32_to_float32(val, &env->fp_status);
     85 }
     86 
     87 uint64_t HELPER(ftoid)(CPUOpenRISCState *env, uint64_t val)
     88 {
     89     return float64_to_int64_round_to_zero(val, &env->fp_status);
     90 }
     91 
     92 uint32_t HELPER(ftois)(CPUOpenRISCState *env, uint32_t val)
     93 {
     94     return float32_to_int32_round_to_zero(val, &env->fp_status);
     95 }
     96 
     97 uint64_t HELPER(stod)(CPUOpenRISCState *env, uint32_t val)
     98 {
     99     return float32_to_float64(val, &env->fp_status);
    100 }
    101 
    102 uint32_t HELPER(dtos)(CPUOpenRISCState *env, uint64_t val)
    103 {
    104     return float64_to_float32(val, &env->fp_status);
    105 }
    106 
    107 #define FLOAT_CALC(name)                                                  \
    108 uint64_t helper_float_ ## name ## _d(CPUOpenRISCState *env,               \
    109                                      uint64_t fdt0, uint64_t fdt1)        \
    110 { return float64_ ## name(fdt0, fdt1, &env->fp_status); }                 \
    111 uint32_t helper_float_ ## name ## _s(CPUOpenRISCState *env,               \
    112                                      uint32_t fdt0, uint32_t fdt1)        \
    113 { return float32_ ## name(fdt0, fdt1, &env->fp_status); }
    114 
    115 FLOAT_CALC(add)
    116 FLOAT_CALC(sub)
    117 FLOAT_CALC(mul)
    118 FLOAT_CALC(div)
    119 FLOAT_CALC(rem)
    120 #undef FLOAT_CALC
    121 
    122 
    123 uint64_t helper_float_madd_d(CPUOpenRISCState *env, uint64_t a,
    124                              uint64_t b, uint64_t c)
    125 {
    126     /* Note that or1ksim doesn't use fused operation.  */
    127     b = float64_mul(b, c, &env->fp_status);
    128     return float64_add(a, b, &env->fp_status);
    129 }
    130 
    131 uint32_t helper_float_madd_s(CPUOpenRISCState *env, uint32_t a,
    132                              uint32_t b, uint32_t c)
    133 {
    134     /* Note that or1ksim doesn't use fused operation.  */
    135     b = float32_mul(b, c, &env->fp_status);
    136     return float32_add(a, b, &env->fp_status);
    137 }
    138 
    139 
    140 #define FLOAT_CMP(name, impl)                                             \
    141 target_ulong helper_float_ ## name ## _d(CPUOpenRISCState *env,           \
    142                                          uint64_t fdt0, uint64_t fdt1)    \
    143 { return float64_ ## impl(fdt0, fdt1, &env->fp_status); }                 \
    144 target_ulong helper_float_ ## name ## _s(CPUOpenRISCState *env,           \
    145                                          uint32_t fdt0, uint32_t fdt1)    \
    146 { return float32_ ## impl(fdt0, fdt1, &env->fp_status); }
    147 
    148 FLOAT_CMP(le, le)
    149 FLOAT_CMP(lt, lt)
    150 FLOAT_CMP(eq, eq_quiet)
    151 FLOAT_CMP(un, unordered_quiet)
    152 #undef FLOAT_CMP
    153 
    154 #define FLOAT_UCMP(name, expr) \
    155 target_ulong helper_float_ ## name ## _d(CPUOpenRISCState *env,           \
    156                                          uint64_t fdt0, uint64_t fdt1)    \
    157 {                                                                         \
    158     FloatRelation r = float64_compare_quiet(fdt0, fdt1, &env->fp_status); \
    159     return expr;                                                          \
    160 }                                                                         \
    161 target_ulong helper_float_ ## name ## _s(CPUOpenRISCState *env,           \
    162                                          uint32_t fdt0, uint32_t fdt1)    \
    163 {                                                                         \
    164     FloatRelation r = float32_compare_quiet(fdt0, fdt1, &env->fp_status); \
    165     return expr;                                                          \
    166 }
    167 
    168 FLOAT_UCMP(ueq, r == float_relation_equal || r == float_relation_unordered)
    169 FLOAT_UCMP(ult, r == float_relation_less || r == float_relation_unordered)
    170 FLOAT_UCMP(ule, r != float_relation_greater)
    171 #undef FLOAT_UCMP