sim/aarch64/memory.c

   1 /* memory.c -- Memory accessor functions for the AArch64 simulator
   2
   3    Copyright (C) 2015-2020 Free Software Foundation, Inc.
   4
   5    Contributed by Red Hat.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #include "config.h"
  23 #include <sys/types.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27
  28 #include "libiberty.h"
  29
  30 #include "memory.h"
  31 #include "simulator.h"
  32
  33 #include "sim-core.h"
  34
  35 static inline void
  36 mem_error (sim_cpu *cpu, const char *message, uint64_t addr)
  37 {
  38   TRACE_MEMORY (cpu, "ERROR: %s: %" PRIx64, message, addr);
  39 }
  40
  41 /* FIXME: AArch64 requires aligned memory access if SCTRLR_ELx.A is set,
  42    but we are not implementing that here.  */
  43 #define FETCH_FUNC64(RETURN_TYPE, ACCESS_TYPE, NAME, N)                 \
  44   RETURN_TYPE                                                           \
  45   aarch64_get_mem_##NAME (sim_cpu *cpu, uint64_t address)               \
  46   {                                                                     \
  47     RETURN_TYPE val = (RETURN_TYPE) (ACCESS_TYPE)                       \
  48       sim_core_read_unaligned_##N (cpu, 0, read_map, address);          \
  49     TRACE_MEMORY (cpu, "read of %" PRIx64 " (%d bytes) from %" PRIx64,  \
  50                   val, N, address);                                     \
  51                                                                         \
  52     return val;                                                         \
  53   }
  54
  55 FETCH_FUNC64 (uint64_t, uint64_t, u64, 8)
  56 FETCH_FUNC64 (int64_t,   int64_t, s64, 8)
  57
  58 #define FETCH_FUNC32(RETURN_TYPE, ACCESS_TYPE, NAME, N)                 \
  59   RETURN_TYPE                                                           \
  60   aarch64_get_mem_##NAME (sim_cpu *cpu, uint64_t address)               \
  61   {                                                                     \
  62     RETURN_TYPE val = (RETURN_TYPE) (ACCESS_TYPE)                       \
  63       sim_core_read_unaligned_##N (cpu, 0, read_map, address);          \
  64     TRACE_MEMORY (cpu, "read of %8x (%d bytes) from %" PRIx64,          \
  65                   val, N, address);                                     \
  66                                                                         \
  67     return val;                                                         \
  68   }
  69
  70 FETCH_FUNC32 (uint32_t, uint32_t, u32, 4)
  71 FETCH_FUNC32 (int32_t,   int32_t, s32, 4)
  72 FETCH_FUNC32 (uint32_t, uint16_t, u16, 2)
  73 FETCH_FUNC32 (int32_t,   int16_t, s16, 2)
  74 FETCH_FUNC32 (uint32_t,  uint8_t, u8, 1)
  75 FETCH_FUNC32 (int32_t,    int8_t, s8, 1)
  76
  77 void
  78 aarch64_get_mem_long_double (sim_cpu *cpu, uint64_t address, FRegister *a)
  79 {
  80   a->v[0] = sim_core_read_unaligned_8 (cpu, 0, read_map, address);
  81   a->v[1] = sim_core_read_unaligned_8 (cpu, 0, read_map, address + 8);
  82 }
  83
  84 /* FIXME: Aarch64 requires aligned memory access if SCTRLR_ELx.A is set,
  85    but we are not implementing that here.  */
  86 #define STORE_FUNC(TYPE, NAME, N)                                       \
  87   void                                                                  \
  88   aarch64_set_mem_##NAME (sim_cpu *cpu, uint64_t address, TYPE value)   \
  89   {                                                                     \
  90     TRACE_MEMORY (cpu,                                                  \
  91                   "write of %" PRIx64 " (%d bytes) to %" PRIx64,        \
  92                   (uint64_t) value, N, address);                        \
  93                                                                         \
  94     sim_core_write_unaligned_##N (cpu, 0, write_map, address, value);   \
  95   }
  96
  97 STORE_FUNC (uint64_t, u64, 8)
  98 STORE_FUNC (int64_t,  s64, 8)
  99 STORE_FUNC (uint32_t, u32, 4)
 100 STORE_FUNC (int32_t,  s32, 4)
 101 STORE_FUNC (uint16_t, u16, 2)
 102 STORE_FUNC (int16_t,  s16, 2)
 103 STORE_FUNC (uint8_t,  u8, 1)
 104 STORE_FUNC (int8_t,   s8, 1)
 105
 106 void
 107 aarch64_set_mem_long_double (sim_cpu *cpu, uint64_t address, FRegister a)
 108 {
 109   TRACE_MEMORY (cpu,
 110                 "write of long double %" PRIx64 " %" PRIx64 " to %" PRIx64,
 111                 a.v[0], a.v[1], address);
 112
 113   sim_core_write_unaligned_8 (cpu, 0, write_map, address, a.v[0]);
 114   sim_core_write_unaligned_8 (cpu, 0, write_map, address + 8, a.v[1]);
 115 }
 116
 117 void
 118 aarch64_get_mem_blk (sim_cpu *  cpu,
 119                      uint64_t   address,
 120                      char *     buffer,
 121                      unsigned   length)
 122 {
 123   unsigned len;
 124
 125   len = sim_core_read_buffer (CPU_STATE (cpu), cpu, read_map,
 126                               buffer, address, length);
 127   if (len == length)
 128     return;
 129
 130   memset (buffer, 0, length);
 131   if (cpu)
 132     mem_error (cpu, "read of non-existant mem block at", address);
 133
 134   sim_engine_halt (CPU_STATE (cpu), cpu, NULL, aarch64_get_PC (cpu),
 135                    sim_stopped, SIM_SIGBUS);
 136 }
 137
 138 const char *
 139 aarch64_get_mem_ptr (sim_cpu *cpu, uint64_t address)
 140 {
 141   char *addr = sim_core_trans_addr (CPU_STATE (cpu), cpu, read_map, address);
 142
 143   if (addr == NULL)
 144     {
 145       mem_error (cpu, "request for non-existant mem addr of", address);
 146       sim_engine_halt (CPU_STATE (cpu), cpu, NULL, aarch64_get_PC (cpu),
 147                        sim_stopped, SIM_SIGBUS);
 148     }
 149
 150   return addr;
 151 }
 152
 153 /* We implement a combined stack and heap.  That way the sbrk()
 154    function in libgloss/aarch64/syscalls.c has a chance to detect
 155    an out-of-memory condition by noticing a stack/heap collision.
 156
 157    The heap starts at the end of loaded memory and carries on up
 158    to an arbitary 2Gb limit.  */
 159
 160 uint64_t
 161 aarch64_get_heap_start (sim_cpu *cpu)
 162 {
 163   uint64_t heap = trace_sym_value (CPU_STATE (cpu), "end");
 164
 165   if (heap == 0)
 166     heap = trace_sym_value (CPU_STATE (cpu), "_end");
 167   if (heap == 0)
 168     {
 169       heap = STACK_TOP - 0x100000;
 170       sim_io_eprintf (CPU_STATE (cpu),
 171                       "Unable to find 'end' symbol - using addr based "
 172                       "upon stack instead %" PRIx64 "\n",
 173                       heap);
 174     }
 175   return heap;
 176 }
 177
 178 uint64_t
 179 aarch64_get_stack_start (sim_cpu *cpu)
 180 {
 181   if (aarch64_get_heap_start (cpu) >= STACK_TOP)
 182     mem_error (cpu, "executable is too big", aarch64_get_heap_start (cpu));
 183   return STACK_TOP;
 184 }