target-sparc/helper.c

   1 /*
   2  *  Misc Sparc helpers
   3  *
   4  *  Copyright (c) 2003-2005 Fabrice Bellard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "cpu.h"
  21 #include "qemu/host-utils.h"
  22 #include "helper.h"
  23 #include "sysemu/sysemu.h"
  24
  25 void helper_raise_exception(CPUSPARCState *env, int tt)
  26 {
  27     CPUState *cs = CPU(sparc_env_get_cpu(env));
  28
  29     cs->exception_index = tt;
  30     cpu_loop_exit(cs);
  31 }
  32
  33 void helper_debug(CPUSPARCState *env)
  34 {
  35     CPUState *cs = CPU(sparc_env_get_cpu(env));
  36
  37     cs->exception_index = EXCP_DEBUG;
  38     cpu_loop_exit(cs);
  39 }
  40
  41 #ifdef TARGET_SPARC64
  42 target_ulong helper_popc(target_ulong val)
  43 {
  44     return ctpop64(val);
  45 }
  46
  47 void helper_tick_set_count(void *opaque, uint64_t count)
  48 {
  49 #if !defined(CONFIG_USER_ONLY)
  50     cpu_tick_set_count(opaque, count);
  51 #endif
  52 }
  53
  54 uint64_t helper_tick_get_count(void *opaque)
  55 {
  56 #if !defined(CONFIG_USER_ONLY)
  57     return cpu_tick_get_count(opaque);
  58 #else
  59     return 0;
  60 #endif
  61 }
  62
  63 void helper_tick_set_limit(void *opaque, uint64_t limit)
  64 {
  65 #if !defined(CONFIG_USER_ONLY)
  66     cpu_tick_set_limit(opaque, limit);
  67 #endif
  68 }
  69 #endif
  70
  71 static target_ulong helper_udiv_common(CPUSPARCState *env, target_ulong a,
  72                                        target_ulong b, int cc)
  73 {
  74     SPARCCPU *cpu = sparc_env_get_cpu(env);
  75     int overflow = 0;
  76     uint64_t x0;
  77     uint32_t x1;
  78
  79     x0 = (a & 0xffffffff) | ((int64_t) (env->y) << 32);
  80     x1 = (b & 0xffffffff);
  81
  82     if (x1 == 0) {
  83         cpu_restore_state(CPU(cpu), GETPC());
  84         helper_raise_exception(env, TT_DIV_ZERO);
  85     }
  86
  87     x0 = x0 / x1;
  88     if (x0 > 0xffffffff) {
  89         x0 = 0xffffffff;
  90         overflow = 1;
  91     }
  92
  93     if (cc) {
  94         env->cc_dst = x0;
  95         env->cc_src2 = overflow;
  96         env->cc_op = CC_OP_DIV;
  97     }
  98     return x0;
  99 }
 100
 101 target_ulong helper_udiv(CPUSPARCState *env, target_ulong a, target_ulong b)
 102 {
 103     return helper_udiv_common(env, a, b, 0);
 104 }
 105
 106 target_ulong helper_udiv_cc(CPUSPARCState *env, target_ulong a, target_ulong b)
 107 {
 108     return helper_udiv_common(env, a, b, 1);
 109 }
 110
 111 static target_ulong helper_sdiv_common(CPUSPARCState *env, target_ulong a,
 112                                        target_ulong b, int cc)
 113 {
 114     SPARCCPU *cpu = sparc_env_get_cpu(env);
 115     int overflow = 0;
 116     int64_t x0;
 117     int32_t x1;
 118
 119     x0 = (a & 0xffffffff) | ((int64_t) (env->y) << 32);
 120     x1 = (b & 0xffffffff);
 121
 122     if (x1 == 0) {
 123         cpu_restore_state(CPU(cpu), GETPC());
 124         helper_raise_exception(env, TT_DIV_ZERO);
 125     }
 126
 127     x0 = x0 / x1;
 128     if ((int32_t) x0 != x0) {
 129         x0 = x0 < 0 ? 0x80000000 : 0x7fffffff;
 130         overflow = 1;
 131     }
 132
 133     if (cc) {
 134         env->cc_dst = x0;
 135         env->cc_src2 = overflow;
 136         env->cc_op = CC_OP_DIV;
 137     }
 138     return x0;
 139 }
 140
 141 target_ulong helper_sdiv(CPUSPARCState *env, target_ulong a, target_ulong b)
 142 {
 143     return helper_sdiv_common(env, a, b, 0);
 144 }
 145
 146 target_ulong helper_sdiv_cc(CPUSPARCState *env, target_ulong a, target_ulong b)
 147 {
 148     return helper_sdiv_common(env, a, b, 1);
 149 }
 150
 151 #ifdef TARGET_SPARC64
 152 int64_t helper_sdivx(CPUSPARCState *env, int64_t a, int64_t b)
 153 {
 154     if (b == 0) {
 155         /* Raise divide by zero trap.  */
 156         SPARCCPU *cpu = sparc_env_get_cpu(env);
 157
 158         cpu_restore_state(CPU(cpu), GETPC());
 159         helper_raise_exception(env, TT_DIV_ZERO);
 160     } else if (b == -1) {
 161         /* Avoid overflow trap with i386 divide insn.  */
 162         return -a;
 163     } else {
 164         return a / b;
 165     }
 166 }
 167
 168 uint64_t helper_udivx(CPUSPARCState *env, uint64_t a, uint64_t b)
 169 {
 170     if (b == 0) {
 171         /* Raise divide by zero trap.  */
 172         SPARCCPU *cpu = sparc_env_get_cpu(env);
 173
 174         cpu_restore_state(CPU(cpu), GETPC());
 175         helper_raise_exception(env, TT_DIV_ZERO);
 176     }
 177     return a / b;
 178 }
 179 #endif
 180
 181 target_ulong helper_taddcctv(CPUSPARCState *env, target_ulong src1,
 182                              target_ulong src2)
 183 {
 184     SPARCCPU *cpu = sparc_env_get_cpu(env);
 185     target_ulong dst;
 186
 187     /* Tag overflow occurs if either input has bits 0 or 1 set.  */
 188     if ((src1 | src2) & 3) {
 189         goto tag_overflow;
 190     }
 191
 192     dst = src1 + src2;
 193
 194     /* Tag overflow occurs if the addition overflows.  */
 195     if (~(src1 ^ src2) & (src1 ^ dst) & (1u << 31)) {
 196         goto tag_overflow;
 197     }
 198
 199     /* Only modify the CC after any exceptions have been generated.  */
 200     env->cc_op = CC_OP_TADDTV;
 201     env->cc_src = src1;
 202     env->cc_src2 = src2;
 203     env->cc_dst = dst;
 204     return dst;
 205
 206  tag_overflow:
 207     cpu_restore_state(CPU(cpu), GETPC());
 208     helper_raise_exception(env, TT_TOVF);
 209 }
 210
 211 target_ulong helper_tsubcctv(CPUSPARCState *env, target_ulong src1,
 212                              target_ulong src2)
 213 {
 214     SPARCCPU *cpu = sparc_env_get_cpu(env);
 215     target_ulong dst;
 216
 217     /* Tag overflow occurs if either input has bits 0 or 1 set.  */
 218     if ((src1 | src2) & 3) {
 219         goto tag_overflow;
 220     }
 221
 222     dst = src1 - src2;
 223
 224     /* Tag overflow occurs if the subtraction overflows.  */
 225     if ((src1 ^ src2) & (src1 ^ dst) & (1u << 31)) {
 226         goto tag_overflow;
 227     }
 228
 229     /* Only modify the CC after any exceptions have been generated.  */
 230     env->cc_op = CC_OP_TSUBTV;
 231     env->cc_src = src1;
 232     env->cc_src2 = src2;
 233     env->cc_dst = dst;
 234     return dst;
 235
 236  tag_overflow:
 237     cpu_restore_state(CPU(cpu), GETPC());
 238     helper_raise_exception(env, TT_TOVF);
 239 }
 240
 241 #ifndef TARGET_SPARC64
 242 void helper_power_down(CPUSPARCState *env)
 243 {
 244     CPUState *cs = CPU(sparc_env_get_cpu(env));
 245
 246     cs->halted = 1;
 247     cs->exception_index = EXCP_HLT;
 248     env->pc = env->npc;
 249     env->npc = env->pc + 4;
 250     cpu_loop_exit(cs);
 251 }
 252 #endif