target/i386/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 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 "tcg.h"
  27
  28 void helper_cmpxchg8b_unlocked(CPUX86State *env, target_ulong a0)
  29 {
  30     uintptr_t ra = GETPC();
  31     uint64_t oldv, cmpv, newv;
  32     int eflags;
  33
  34     eflags = cpu_cc_compute_all(env, CC_OP);
  35
  36     cmpv = deposit64(env->regs[R_EAX], 32, 32, env->regs[R_EDX]);
  37     newv = deposit64(env->regs[R_EBX], 32, 32, env->regs[R_ECX]);
  38
  39     oldv = cpu_ldq_data_ra(env, a0, ra);
  40     newv = (cmpv == oldv ? newv : oldv);
  41     /* always do the store */
  42     cpu_stq_data_ra(env, a0, newv, ra);
  43
  44     if (oldv == cmpv) {
  45         eflags |= CC_Z;
  46     } else {
  47         env->regs[R_EAX] = (uint32_t)oldv;
  48         env->regs[R_EDX] = (uint32_t)(oldv >> 32);
  49         eflags &= ~CC_Z;
  50     }
  51     CC_SRC = eflags;
  52 }
  53
  54 void helper_cmpxchg8b(CPUX86State *env, target_ulong a0)
  55 {
  56 #ifdef CONFIG_ATOMIC64
  57     uint64_t oldv, cmpv, newv;
  58     int eflags;
  59
  60     eflags = cpu_cc_compute_all(env, CC_OP);
  61
  62     cmpv = deposit64(env->regs[R_EAX], 32, 32, env->regs[R_EDX]);
  63     newv = deposit64(env->regs[R_EBX], 32, 32, env->regs[R_ECX]);
  64
  65 #ifdef CONFIG_USER_ONLY
  66     {
  67         uint64_t *haddr = g2h(a0);
  68         cmpv = cpu_to_le64(cmpv);
  69         newv = cpu_to_le64(newv);
  70         oldv = atomic_cmpxchg__nocheck(haddr, cmpv, newv);
  71         oldv = le64_to_cpu(oldv);
  72     }
  73 #else
  74     {
  75         uintptr_t ra = GETPC();
  76         int mem_idx = cpu_mmu_index(env, false);
  77         TCGMemOpIdx oi = make_memop_idx(MO_TEQ, mem_idx);
  78         oldv = helper_atomic_cmpxchgq_le_mmu(env, a0, cmpv, newv, oi, ra);
  79     }
  80 #endif
  81
  82     if (oldv == cmpv) {
  83         eflags |= CC_Z;
  84     } else {
  85         env->regs[R_EAX] = (uint32_t)oldv;
  86         env->regs[R_EDX] = (uint32_t)(oldv >> 32);
  87         eflags &= ~CC_Z;
  88     }
  89     CC_SRC = eflags;
  90 #else
  91     cpu_loop_exit_atomic(ENV_GET_CPU(env), GETPC());
  92 #endif /* CONFIG_ATOMIC64 */
  93 }
  94
  95 #ifdef TARGET_X86_64
  96 void helper_cmpxchg16b_unlocked(CPUX86State *env, target_ulong a0)
  97 {
  98     uintptr_t ra = GETPC();
  99     Int128 oldv, cmpv, newv;
 100     uint64_t o0, o1;
 101     int eflags;
 102     bool success;
 103
 104     if ((a0 & 0xf) != 0) {
 105         raise_exception_ra(env, EXCP0D_GPF, GETPC());
 106     }
 107     eflags = cpu_cc_compute_all(env, CC_OP);
 108
 109     cmpv = int128_make128(env->regs[R_EAX], env->regs[R_EDX]);
 110     newv = int128_make128(env->regs[R_EBX], env->regs[R_ECX]);
 111
 112     o0 = cpu_ldq_data_ra(env, a0 + 0, ra);
 113     o1 = cpu_ldq_data_ra(env, a0 + 8, ra);
 114
 115     oldv = int128_make128(o0, o1);
 116     success = int128_eq(oldv, cmpv);
 117     if (!success) {
 118         newv = oldv;
 119     }
 120
 121     cpu_stq_data_ra(env, a0 + 0, int128_getlo(newv), ra);
 122     cpu_stq_data_ra(env, a0 + 8, int128_gethi(newv), ra);
 123
 124     if (success) {
 125         eflags |= CC_Z;
 126     } else {
 127         env->regs[R_EAX] = int128_getlo(oldv);
 128         env->regs[R_EDX] = int128_gethi(oldv);
 129         eflags &= ~CC_Z;
 130     }
 131     CC_SRC = eflags;
 132 }
 133
 134 void helper_cmpxchg16b(CPUX86State *env, target_ulong a0)
 135 {
 136     uintptr_t ra = GETPC();
 137
 138     if ((a0 & 0xf) != 0) {
 139         raise_exception_ra(env, EXCP0D_GPF, ra);
 140     } else {
 141 #ifndef CONFIG_ATOMIC128
 142         cpu_loop_exit_atomic(ENV_GET_CPU(env), ra);
 143 #else
 144         int eflags = cpu_cc_compute_all(env, CC_OP);
 145
 146         Int128 cmpv = int128_make128(env->regs[R_EAX], env->regs[R_EDX]);
 147         Int128 newv = int128_make128(env->regs[R_EBX], env->regs[R_ECX]);
 148
 149         int mem_idx = cpu_mmu_index(env, false);
 150         TCGMemOpIdx oi = make_memop_idx(MO_TEQ | MO_ALIGN_16, mem_idx);
 151         Int128 oldv = helper_atomic_cmpxchgo_le_mmu(env, a0, cmpv,
 152                                                     newv, oi, ra);
 153
 154         if (int128_eq(oldv, cmpv)) {
 155             eflags |= CC_Z;
 156         } else {
 157             env->regs[R_EAX] = int128_getlo(oldv);
 158             env->regs[R_EDX] = int128_gethi(oldv);
 159             eflags &= ~CC_Z;
 160         }
 161         CC_SRC = eflags;
 162 #endif
 163     }
 164 }
 165 #endif
 166
 167 void helper_boundw(CPUX86State *env, target_ulong a0, int v)
 168 {
 169     int low, high;
 170
 171     low = cpu_ldsw_data_ra(env, a0, GETPC());
 172     high = cpu_ldsw_data_ra(env, a0 + 2, GETPC());
 173     v = (int16_t)v;
 174     if (v < low || v > high) {
 175         if (env->hflags & HF_MPX_EN_MASK) {
 176             env->bndcs_regs.sts = 0;
 177         }
 178         raise_exception_ra(env, EXCP05_BOUND, GETPC());
 179     }
 180 }
 181
 182 void helper_boundl(CPUX86State *env, target_ulong a0, int v)
 183 {
 184     int low, high;
 185
 186     low = cpu_ldl_data_ra(env, a0, GETPC());
 187     high = cpu_ldl_data_ra(env, a0 + 4, GETPC());
 188     if (v < low || v > high) {
 189         if (env->hflags & HF_MPX_EN_MASK) {
 190             env->bndcs_regs.sts = 0;
 191         }
 192         raise_exception_ra(env, EXCP05_BOUND, GETPC());
 193     }
 194 }
 195
 196 #if !defined(CONFIG_USER_ONLY)
 197 /* try to fill the TLB and return an exception if error. If retaddr is
 198  * NULL, it means that the function was called in C code (i.e. not
 199  * from generated code or from helper.c)
 200  */
 201 /* XXX: fix it to restore all registers */
 202 void tlb_fill(CPUState *cs, target_ulong addr, MMUAccessType access_type,
 203               int mmu_idx, uintptr_t retaddr)
 204 {
 205     int ret;
 206
 207     ret = x86_cpu_handle_mmu_fault(cs, addr, access_type, mmu_idx);
 208     if (ret) {
 209         X86CPU *cpu = X86_CPU(cs);
 210         CPUX86State *env = &cpu->env;
 211
 212         raise_exception_err_ra(env, cs->exception_index, env->error_code, retaddr);
 213     }
 214 }
 215 #endif