gdb: turn gdb::bcache's function pointers into virtual methods

The two function pointers optionally passed to gdb::bcache are very good
candidates to be turned into virtual methods, this patch does that in
the most straightforward / unsurprising way.

gdb/ChangeLog:

	* bcache.h (struct bcache) <bcache>: Remove constructor.
	<m_hash_function, m_compare_function>: Remove.
	<~bcache>: Make virtual.
	<compare>: Remove static method, introduce virtual method.
	<default_hash>: Remove.
	<hash>: New virtual method.
	* bcache.c (bcache::expand_hash_table): Update.
	(bcache::insert): Update.
	(bcache::hash): New.
	(bcache::compare): Update comment and parameter names.
	* gdbtypes.c (types_deeply_equal): Update.
	* psymtab.h (struct psymbol_bcache): New struct.
	(class psymtab_storage) <psymtab_storage>: Make default.
	<psymbol_cache>: Change type to psymbol_bcache.
	* psymtab.c (psymtab_storage::psymtab_storage): Remove.
	(psymbol_hash): Change to...
	(psymbol_bcache::hash): ... this.
	(psymbol_compare): Change to...
	(psymbol_bcache::compare): ... this.

Change-Id: I41d578e61de8ac1163461a28fbd220d1f855e372

1 files changed, 18 insertions, 4 deletions

diff --git a/gdb/psymtab.h b/gdb/psymtab.h
index e8bafbe..3c2d65f 100644
--- a/gdb/psymtab.h
+++ b/gdb/psymtab.h
@@ -27,6 +27,22 @@
 
 struct partial_symbol;
 
+/* Specialization of bcache to store partial symbols.  */
+
+struct psymbol_bcache : public gdb::bcache
+{
+  /* Calculate a hash code for the given partial symbol.  The hash is
+     calculated using the symbol's value, language, domain, class
+     and name.  These are the values which are set by
+     add_psymbol_to_bcache.  */
+  unsigned long hash (const void *addr, int length) override;
+
+  /* Returns true if the symbol LEFT equals the symbol RIGHT.
+     For the comparison this function uses a symbols value,
+     language, domain, class and name.  */
+  int compare (const void *left, const void *right, int length) override;
+};
+
 /* An instance of this class manages the partial symbol tables and
    partial symbols for a given objfile.
 
@@ -48,9 +64,7 @@ struct partial_symbol;
 class psymtab_storage
 {
 public:
-
-  psymtab_storage ();
-
+  psymtab_storage () = default;
   ~psymtab_storage ();
 
   DISABLE_COPY_AND_ASSIGN (psymtab_storage);
@@ -121,7 +135,7 @@ public:
   /* A byte cache where we can stash arbitrary "chunks" of bytes that
      will not change.  */
 
-  gdb::bcache psymbol_cache;
+  psymbol_bcache psymbol_cache;
 
   /* Vectors of all partial symbols read in from file.  The actual data
      is stored in the objfile_obstack.  */