target/i386/tcg/mem_helper.c

   1 /*
   2  *  x86 memory access helpers
   3  *
   4  *  Copyright (c) 2003 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 2.1 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 "qemu/osdep.h"
  21 #include "cpu.h"
  22 #include "exec/helper-proto.h"
  23 #include "exec/exec-all.h"
  24 #include "exec/cpu_ldst.h"
  25 #include "qemu/int128.h"
  26 #include "qemu/atomic128.h"
  27 #include "tcg/tcg.h"
  28 #include "helper-tcg.h"
  29
  30 void helper_cmpxchg8b_unlocked(CPUX86State *env, target_ulong a0)
  31 {
  32     uintptr_t ra = GETPC();
  33     uint64_t oldv, cmpv, newv;
  34     int eflags;
  35
  36     eflags = cpu_cc_compute_all(env, CC_OP);
  37
  38     cmpv = deposit64(env->regs[R_EAX], 32, 32, env->regs[R_EDX]);
  39     newv = deposit64(env->regs[R_EBX], 32, 32, env->regs[R_ECX]);
  40
  41     oldv = cpu_ldq_data_ra(env, a0, ra);
  42     newv = (cmpv == oldv ? newv : oldv);
  43     /* always do the store */
  44     cpu_stq_data_ra(env, a0, newv, ra);
  45
  46     if (oldv == cmpv) {
  47         eflags |= CC_Z;
  48     } else {
  49         env->regs[R_EAX] = (uint32_t)oldv;
  50         env->regs[R_EDX] = (uint32_t)(oldv >> 32);
  51         eflags &= ~CC_Z;
  52     }
  53     CC_SRC = eflags;
  54 }
  55
  56 void helper_cmpxchg8b(CPUX86State *env, target_ulong a0)
  57 {
  58 #ifdef CONFIG_ATOMIC64
  59     uint64_t oldv, cmpv, newv;
  60     int eflags;
  61
  62     eflags = cpu_cc_compute_all(env, CC_OP);
  63
  64     cmpv = deposit64(env->regs[R_EAX], 32, 32, env->regs[R_EDX]);
  65     newv = deposit64(env->regs[R_EBX], 32, 32, env->regs[R_ECX]);
  66
  67     {
  68         uintptr_t ra = GETPC();
  69         int mem_idx = cpu_mmu_index(env, false);
  70         TCGMemOpIdx oi = make_memop_idx(MO_TEQ, mem_idx);
  71         oldv = cpu_atomic_cmpxchgq_le_mmu(env, a0, cmpv, newv, oi, ra);
  72     }
  73
  74     if (oldv == cmpv) {
  75         eflags |= CC_Z;
  76     } else {
  77         env->regs[R_EAX] = (uint32_t)oldv;
  78         env->regs[R_EDX] = (uint32_t)(oldv >> 32);
  79         eflags &= ~CC_Z;
  80     }
  81     CC_SRC = eflags;
  82 #else
  83     cpu_loop_exit_atomic(env_cpu(env), GETPC());
  84 #endif /* CONFIG_ATOMIC64 */
  85 }
  86
  87 #ifdef TARGET_X86_64
  88 void helper_cmpxchg16b_unlocked(CPUX86State *env, target_ulong a0)
  89 {
  90     uintptr_t ra = GETPC();
  91     Int128 oldv, cmpv, newv;
  92     uint64_t o0, o1;
  93     int eflags;
  94     bool success;
  95
  96     if ((a0 & 0xf) != 0) {
  97         raise_exception_ra(env, EXCP0D_GPF, GETPC());
  98     }
  99     eflags = cpu_cc_compute_all(env, CC_OP);
 100
 101     cmpv = int128_make128(env->regs[R_EAX], env->regs[R_EDX]);
 102     newv = int128_make128(env->regs[R_EBX], env->regs[R_ECX]);
 103
 104     o0 = cpu_ldq_data_ra(env, a0 + 0, ra);
 105     o1 = cpu_ldq_data_ra(env, a0 + 8, ra);
 106
 107     oldv = int128_make128(o0, o1);
 108     success = int128_eq(oldv, cmpv);
 109     if (!success) {
 110         newv = oldv;
 111     }
 112
 113     cpu_stq_data_ra(env, a0 + 0, int128_getlo(newv), ra);
 114     cpu_stq_data_ra(env, a0 + 8, int128_gethi(newv), ra);
 115
 116     if (success) {
 117         eflags |= CC_Z;
 118     } else {
 119         env->regs[R_EAX] = int128_getlo(oldv);
 120         env->regs[R_EDX] = int128_gethi(oldv);
 121         eflags &= ~CC_Z;
 122     }
 123     CC_SRC = eflags;
 124 }
 125
 126 void helper_cmpxchg16b(CPUX86State *env, target_ulong a0)
 127 {
 128     uintptr_t ra = GETPC();
 129
 130     if ((a0 & 0xf) != 0) {
 131         raise_exception_ra(env, EXCP0D_GPF, ra);
 132     } else if (HAVE_CMPXCHG128) {
 133         int eflags = cpu_cc_compute_all(env, CC_OP);
 134
 135         Int128 cmpv = int128_make128(env->regs[R_EAX], env->regs[R_EDX]);
 136         Int128 newv = int128_make128(env->regs[R_EBX], env->regs[R_ECX]);
 137
 138         int mem_idx = cpu_mmu_index(env, false);
 139         TCGMemOpIdx oi = make_memop_idx(MO_TEQ | MO_ALIGN_16, mem_idx);
 140         Int128 oldv = cpu_atomic_cmpxchgo_le_mmu(env, a0, cmpv, newv, oi, ra);
 141
 142         if (int128_eq(oldv, cmpv)) {
 143             eflags |= CC_Z;
 144         } else {
 145             env->regs[R_EAX] = int128_getlo(oldv);
 146             env->regs[R_EDX] = int128_gethi(oldv);
 147             eflags &= ~CC_Z;
 148         }
 149         CC_SRC = eflags;
 150     } else {
 151         cpu_loop_exit_atomic(env_cpu(env), ra);
 152     }
 153 }
 154 #endif
 155
 156 void helper_boundw(CPUX86State *env, target_ulong a0, int v)
 157 {
 158     int low, high;
 159
 160     low = cpu_ldsw_data_ra(env, a0, GETPC());
 161     high = cpu_ldsw_data_ra(env, a0 + 2, GETPC());
 162     v = (int16_t)v;
 163     if (v < low || v > high) {
 164         if (env->hflags & HF_MPX_EN_MASK) {
 165             env->bndcs_regs.sts = 0;
 166         }
 167         raise_exception_ra(env, EXCP05_BOUND, GETPC());
 168     }
 169 }
 170
 171 void helper_boundl(CPUX86State *env, target_ulong a0, int v)
 172 {
 173     int low, high;
 174
 175     low = cpu_ldl_data_ra(env, a0, GETPC());
 176     high = cpu_ldl_data_ra(env, a0 + 4, GETPC());
 177     if (v < low || v > high) {
 178         if (env->hflags & HF_MPX_EN_MASK) {
 179             env->bndcs_regs.sts = 0;
 180         }
 181         raise_exception_ra(env, EXCP05_BOUND, GETPC());
 182     }
 183 }