gdb/arch/riscv.c

   1 /* Copyright (C) 2018-2020 Free Software Foundation, Inc.
   2
   3    This file is part of GDB.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  17
  18 #include "gdbsupport/common-defs.h"
  19 #include "riscv.h"
  20 #include <stdlib.h>
  21 #include <unordered_map>
  22
  23 #include "../features/riscv/32bit-cpu.c"
  24 #include "../features/riscv/64bit-cpu.c"
  25 #include "../features/riscv/32bit-fpu.c"
  26 #include "../features/riscv/64bit-fpu.c"
  27
  28 #ifndef GDBSERVER
  29 #define STATIC_IN_GDB static
  30 #else
  31 #define STATIC_IN_GDB
  32 #endif
  33
  34 /* See arch/riscv.h.  */
  35
  36 STATIC_IN_GDB target_desc *
  37 riscv_create_target_description (const struct riscv_gdbarch_features features)
  38 {
  39   /* Now we should create a new target description.  */
  40   target_desc *tdesc = allocate_target_description ();
  41
  42 #ifndef IN_PROCESS_AGENT
  43   std::string arch_name = "riscv";
  44
  45   if (features.xlen == 4)
  46     arch_name.append (":rv32i");
  47   else if (features.xlen == 8)
  48     arch_name.append (":rv64i");
  49   else if (features.xlen == 16)
  50     arch_name.append (":rv128i");
  51
  52   if (features.flen == 4)
  53     arch_name.append ("f");
  54   else if (features.flen == 8)
  55     arch_name.append ("d");
  56   else if (features.flen == 16)
  57     arch_name.append ("q");
  58
  59   set_tdesc_architecture (tdesc, arch_name.c_str ());
  60 #endif
  61
  62   long regnum = 0;
  63
  64   /* For now we only support creating 32-bit or 64-bit x-registers.  */
  65   if (features.xlen == 4)
  66     regnum = create_feature_riscv_32bit_cpu (tdesc, regnum);
  67   else if (features.xlen == 8)
  68     regnum = create_feature_riscv_64bit_cpu (tdesc, regnum);
  69
  70   /* For now we only support creating 32-bit or 64-bit f-registers.  */
  71   if (features.flen == 4)
  72     regnum = create_feature_riscv_32bit_fpu (tdesc, regnum);
  73   else if (features.flen == 8)
  74     regnum = create_feature_riscv_64bit_fpu (tdesc, regnum);
  75
  76   return tdesc;
  77 }
  78
  79 #ifndef GDBSERVER
  80
  81 /* Wrapper used by std::unordered_map to generate hash for feature set.  */
  82 struct riscv_gdbarch_features_hasher
  83 {
  84   std::size_t
  85   operator() (const riscv_gdbarch_features &features) const noexcept
  86   {
  87     return features.hash ();
  88   }
  89 };
  90
  91 /* Cache of previously seen target descriptions, indexed by the feature set
  92    that created them.  */
  93 static std::unordered_map<riscv_gdbarch_features,
  94                           const target_desc_up,
  95                           riscv_gdbarch_features_hasher> riscv_tdesc_cache;
  96
  97 /* See arch/riscv.h.  */
  98
  99 const target_desc *
 100 riscv_lookup_target_description (const struct riscv_gdbarch_features features)
 101 {
 102   /* Lookup in the cache.  If we find it then return the pointer out of
 103      the target_desc_up (which is a unique_ptr).  This is safe as the
 104      riscv_tdesc_cache will exist until GDB exits.  */
 105   const auto it = riscv_tdesc_cache.find (features);
 106   if (it != riscv_tdesc_cache.end ())
 107     return it->second.get ();
 108
 109   target_desc *tdesc = riscv_create_target_description (features);
 110
 111   /* Add to the cache.  Work around a problem with g++ 4.8 (PR96537):
 112      Call the target_desc_up constructor explictly instead of implicitly.  */
 113   riscv_tdesc_cache.emplace (features, target_desc_up (tdesc));
 114
 115   return tdesc;
 116 }
 117
 118 #endif /* !GDBSERVER */