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
  26 /* broken thread support */
  27
  28 #if defined(CONFIG_USER_ONLY)
  29 QemuMutex global_cpu_lock;
  30
  31 void helper_lock(void)
  32 {
  33     qemu_mutex_lock(&global_cpu_lock);
  34 }
  35
  36 void helper_unlock(void)
  37 {
  38     qemu_mutex_unlock(&global_cpu_lock);
  39 }
  40
  41 void helper_lock_init(void)
  42 {
  43     qemu_mutex_init(&global_cpu_lock);
  44 }
  45 #else
  46 void helper_lock(void)
  47 {
  48 }
  49
  50 void helper_unlock(void)
  51 {
  52 }
  53
  54 void helper_lock_init(void)
  55 {
  56 }
  57 #endif
  58
  59 void helper_cmpxchg8b(CPUX86State *env, target_ulong a0)
  60 {
  61     uint64_t d;
  62     int eflags;
  63
  64     eflags = cpu_cc_compute_all(env, CC_OP);
  65     d = cpu_ldq_data_ra(env, a0, GETPC());
  66     if (d == (((uint64_t)env->regs[R_EDX] << 32) | (uint32_t)env->regs[R_EAX])) {
  67         cpu_stq_data_ra(env, a0, ((uint64_t)env->regs[R_ECX] << 32)
  68                                   | (uint32_t)env->regs[R_EBX], GETPC());
  69         eflags |= CC_Z;
  70     } else {
  71         /* always do the store */
  72         cpu_stq_data_ra(env, a0, d, GETPC());
  73         env->regs[R_EDX] = (uint32_t)(d >> 32);
  74         env->regs[R_EAX] = (uint32_t)d;
  75         eflags &= ~CC_Z;
  76     }
  77     CC_SRC = eflags;
  78 }
  79
  80 #ifdef TARGET_X86_64
  81 void helper_cmpxchg16b(CPUX86State *env, target_ulong a0)
  82 {
  83     uint64_t d0, d1;
  84     int eflags;
  85
  86     if ((a0 & 0xf) != 0) {
  87         raise_exception_ra(env, EXCP0D_GPF, GETPC());
  88     }
  89     eflags = cpu_cc_compute_all(env, CC_OP);
  90     d0 = cpu_ldq_data_ra(env, a0, GETPC());
  91     d1 = cpu_ldq_data_ra(env, a0 + 8, GETPC());
  92     if (d0 == env->regs[R_EAX] && d1 == env->regs[R_EDX]) {
  93         cpu_stq_data_ra(env, a0, env->regs[R_EBX], GETPC());
  94         cpu_stq_data_ra(env, a0 + 8, env->regs[R_ECX], GETPC());
  95         eflags |= CC_Z;
  96     } else {
  97         /* always do the store */
  98         cpu_stq_data_ra(env, a0, d0, GETPC());
  99         cpu_stq_data_ra(env, a0 + 8, d1, GETPC());
 100         env->regs[R_EDX] = d1;
 101         env->regs[R_EAX] = d0;
 102         eflags &= ~CC_Z;
 103     }
 104     CC_SRC = eflags;
 105 }
 106 #endif
 107
 108 void helper_boundw(CPUX86State *env, target_ulong a0, int v)
 109 {
 110     int low, high;
 111
 112     low = cpu_ldsw_data_ra(env, a0, GETPC());
 113     high = cpu_ldsw_data_ra(env, a0 + 2, GETPC());
 114     v = (int16_t)v;
 115     if (v < low || v > high) {
 116         if (env->hflags & HF_MPX_EN_MASK) {
 117             env->bndcs_regs.sts = 0;
 118         }
 119         raise_exception_ra(env, EXCP05_BOUND, GETPC());
 120     }
 121 }
 122
 123 void helper_boundl(CPUX86State *env, target_ulong a0, int v)
 124 {
 125     int low, high;
 126
 127     low = cpu_ldl_data_ra(env, a0, GETPC());
 128     high = cpu_ldl_data_ra(env, a0 + 4, GETPC());
 129     if (v < low || v > high) {
 130         if (env->hflags & HF_MPX_EN_MASK) {
 131             env->bndcs_regs.sts = 0;
 132         }
 133         raise_exception_ra(env, EXCP05_BOUND, GETPC());
 134     }
 135 }
 136
 137 #if !defined(CONFIG_USER_ONLY)
 138 /* try to fill the TLB and return an exception if error. If retaddr is
 139  * NULL, it means that the function was called in C code (i.e. not
 140  * from generated code or from helper.c)
 141  */
 142 /* XXX: fix it to restore all registers */
 143 void tlb_fill(CPUState *cs, target_ulong addr, int is_write, int mmu_idx,
 144               uintptr_t retaddr)
 145 {
 146     int ret;
 147
 148     ret = x86_cpu_handle_mmu_fault(cs, addr, is_write, mmu_idx);
 149     if (ret) {
 150         X86CPU *cpu = X86_CPU(cs);
 151         CPUX86State *env = &cpu->env;
 152
 153         raise_exception_err_ra(env, cs->exception_index, env->error_code, retaddr);
 154     }
 155 }
 156 #endif