gdb/arch/riscv.c

   1 /* Copyright (C) 2018-2024 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 "riscv.h"
  19 #include <stdlib.h>
  20 #include <unordered_map>
  21
  22 #include "../features/riscv/32bit-cpu.c"
  23 #include "../features/riscv/64bit-cpu.c"
  24 #include "../features/riscv/32bit-fpu.c"
  25 #include "../features/riscv/64bit-fpu.c"
  26 #include "../features/riscv/rv32e-xregs.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_up
  37 riscv_create_target_description (const struct riscv_gdbarch_features features)
  38 {
  39   /* Now we should create a new target description.  */
  40   target_desc_up tdesc = allocate_target_description ();
  41
  42 #ifndef IN_PROCESS_AGENT
  43   std::string arch_name = "riscv";
  44
  45   if (features.xlen == 4)
  46     {
  47       if (features.embedded)
  48         arch_name.append (":rv32e");
  49       else
  50         arch_name.append (":rv32i");
  51     }
  52   else if (features.xlen == 8)
  53     arch_name.append (":rv64i");
  54   else if (features.xlen == 16)
  55     arch_name.append (":rv128i");
  56
  57   if (features.flen == 4)
  58     arch_name.append ("f");
  59   else if (features.flen == 8)
  60     arch_name.append ("d");
  61   else if (features.flen == 16)
  62     arch_name.append ("q");
  63
  64   set_tdesc_architecture (tdesc.get (), arch_name.c_str ());
  65 #endif
  66
  67   long regnum = 0;
  68
  69   /* For now we only support creating 32-bit or 64-bit x-registers.  */
  70   if (features.xlen == 4)
  71     {
  72       if (features.embedded)
  73         regnum = create_feature_riscv_rv32e_xregs (tdesc.get (), regnum);
  74       else
  75         regnum = create_feature_riscv_32bit_cpu (tdesc.get (), regnum);
  76     }
  77   else if (features.xlen == 8)
  78     regnum = create_feature_riscv_64bit_cpu (tdesc.get (), regnum);
  79
  80   /* For now we only support creating 32-bit or 64-bit f-registers.  */
  81   if (features.flen == 4)
  82     regnum = create_feature_riscv_32bit_fpu (tdesc.get (), regnum);
  83   else if (features.flen == 8)
  84     regnum = create_feature_riscv_64bit_fpu (tdesc.get (), regnum);
  85
  86   /* Currently GDB only supports vector features coming from remote
  87      targets.  We don't support creating vector features on native targets
  88      (yet).  */
  89   if (features.vlen != 0)
  90     error (_("unable to create vector feature"));
  91
  92   return tdesc;
  93 }
  94
  95 #ifndef GDBSERVER
  96
  97 /* Wrapper used by std::unordered_map to generate hash for feature set.  */
  98 struct riscv_gdbarch_features_hasher
  99 {
 100   std::size_t
 101   operator() (const riscv_gdbarch_features &features) const noexcept
 102   {
 103     return features.hash ();
 104   }
 105 };
 106
 107 /* Cache of previously seen target descriptions, indexed by the feature set
 108    that created them.  */
 109 static std::unordered_map<riscv_gdbarch_features,
 110                           const target_desc_up,
 111                           riscv_gdbarch_features_hasher> riscv_tdesc_cache;
 112
 113 /* See arch/riscv.h.  */
 114
 115 const target_desc *
 116 riscv_lookup_target_description (const struct riscv_gdbarch_features features)
 117 {
 118   /* Lookup in the cache.  If we find it then return the pointer out of
 119      the target_desc_up (which is a unique_ptr).  This is safe as the
 120      riscv_tdesc_cache will exist until GDB exits.  */
 121   const auto it = riscv_tdesc_cache.find (features);
 122   if (it != riscv_tdesc_cache.end ())
 123     return it->second.get ();
 124
 125   target_desc_up tdesc (riscv_create_target_description (features));
 126
 127   /* Add to the cache, and return a pointer borrowed from the
 128      target_desc_up.  This is safe as the cache (and the pointers
 129      contained within it) are not deleted until GDB exits.  */
 130   target_desc *ptr = tdesc.get ();
 131   riscv_tdesc_cache.emplace (features, std::move (tdesc));
 132   return ptr;
 133 }
 134
 135 #endif /* !GDBSERVER */