1 files changed, 88 insertions, 0 deletions
diff --git a/gdb/arch/loongarch.c b/gdb/arch/loongarch.c
new file mode 100644
index 0000000..934f6e4
--- /dev/null
+++ b/gdb/arch/loongarch.c
@@ -0,0 +1,88 @@
+/* Copyright (C) 2022 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include "gdbsupport/common-defs.h"
+#include "loongarch.h"
+#include <stdlib.h>
+#include <unordered_map>
+
+/* Target description features.  */
+
+#include "../features/loongarch/base32.c"
+#include "../features/loongarch/base64.c"
+
+static target_desc_up
+loongarch_create_target_description (const struct loongarch_gdbarch_features features)
+{
+  /* Now we should create a new target description.  */
+  target_desc_up tdesc = allocate_target_description ();
+
+  std::string arch_name = "loongarch";
+
+  if (features.xlen == 4)
+    arch_name.append ("32");
+  else if (features.xlen == 8)
+    arch_name.append ("64");
+
+  set_tdesc_architecture (tdesc.get (), arch_name.c_str ());
+
+  long regnum = 0;
+
+  /* For now we only support creating 32-bit or 64-bit x-registers.  */
+  if (features.xlen == 4)
+    regnum = create_feature_loongarch_base32 (tdesc.get (), regnum);
+  else if (features.xlen == 8)
+    regnum = create_feature_loongarch_base64 (tdesc.get (), regnum);
+
+  return tdesc;
+}
+
+/* Wrapper used by std::unordered_map to generate hash for feature set.  */
+struct loongarch_gdbarch_features_hasher
+{
+  std::size_t
+  operator() (const loongarch_gdbarch_features &features) const noexcept
+  {
+    return features.hash ();
+  }
+};
+
+/* Cache of previously seen target descriptions, indexed by the feature set
+   that created them.  */
+static std::unordered_map<loongarch_gdbarch_features,
+			  const target_desc_up,
+			  loongarch_gdbarch_features_hasher> loongarch_tdesc_cache;
+
+const target_desc *
+loongarch_lookup_target_description (const struct loongarch_gdbarch_features features)
+{
+  /* Lookup in the cache.  If we find it then return the pointer out of
+     the target_desc_up (which is a unique_ptr).  This is safe as the
+     loongarch_tdesc_cache will exist until GDB exits.  */
+  const auto it = loongarch_tdesc_cache.find (features);
+  if (it != loongarch_tdesc_cache.end ())
+    return it->second.get ();
+
+  target_desc_up tdesc (loongarch_create_target_description (features));
+
+  /* Add to the cache, and return a pointer borrowed from the
+     target_desc_up.  This is safe as the cache (and the pointers
+     contained within it) are not deleted until GDB exits.  */
+  target_desc *ptr = tdesc.get ();
+  loongarch_tdesc_cache.emplace (features, std::move (tdesc));
+  return ptr;
+}