Use gdb::unordered_set in linespec_state

This patch changes linespec_state to use gdb::unordered_set.  This
simplifies the code a little and removes some manual management.  It
also replaces address_entry with a std::pair, which simplifies the
code even more; and since this is a private type, IMO it doesn't
reduce readability at all.

Approved-By: Simon Marchi <simon.marchi@efficios.com>

diff --git a/gdb/linespec.c b/gdb/linespec.c
index 86dbbacbba8859898b4fbe2e896f66f1256c8aeb..03a76ae6afd227c0b35dbd3307107f76f4feb29a 100644 (file)
--- a/gdb/linespec.c
+++ b/gdb/linespec.c
@@ -76,16 +76,6 @@ enum class linespec_complete_what
   KEYWORD,
 };
 
-/* An address entry is used to ensure that any given location is only
-   added to the result a single time.  It holds an address and the
-   program space from which the address came.  */
-
-struct address_entry
-{
-  struct program_space *pspace;
-  CORE_ADDR addr;
-};
-
 /* A linespec.  Elements of this structure are filled in by a parser
    (either parse_linespec or some other function).  The structure is
    then converted into SALs by convert_linespec_to_sals.  */
@@ -132,29 +122,6 @@ struct linespec_canonical_name
   struct symtab *symtab;
 };
 
-/* A hash function for address_entry.  */
-
-static hashval_t
-hash_address_entry (const void *p)
-{
-  const address_entry *aep = (const address_entry *) p;
-  hashval_t hash;
-
-  hash = iterative_hash_object (aep->pspace, 0);
-  return iterative_hash_object (aep->addr, hash);
-}
-
-/* An equality function for address_entry.  */
-
-static int
-eq_address_entry (const void *a, const void *b)
-{
-  const address_entry *aea = (const address_entry *) a;
-  const address_entry *aeb = (const address_entry *) b;
-
-  return aea->pspace == aeb->pspace && aea->addr == aeb->addr;
-}
-
 /* An instance of this is used to keep all state while linespec
    operates.  This instance is passed around as a 'this' pointer to
    the various implementation methods.  */
@@ -174,9 +141,7 @@ struct linespec_state
       default_line (default_line),
       funfirstline ((flags & DECODE_LINE_FUNFIRSTLINE) ? 1 : 0),
       list_mode ((flags & DECODE_LINE_LIST_MODE) ? 1 : 0),
-      canonical (canonical),
-      addr_set (htab_create_alloc (10, hash_address_entry, eq_address_entry,
-                                  xfree, xcalloc, xfree))
+      canonical (canonical)
   {
   }
 
@@ -187,12 +152,18 @@ struct linespec_state
 
   ~linespec_state ()
   {
-    htab_delete (addr_set);
     xfree (canonical_names);
   }
 
   DISABLE_COPY_AND_ASSIGN (linespec_state);
 
+  /* Add ADDR to the address set.  Return true if this is a new
+     entry.  */
+  bool maybe_add_address (program_space *pspace, CORE_ADDR addr)
+  {
+    return addr_set.emplace (pspace, addr).second;
+  }
+
   /* The language in use during linespec processing.  */
   const struct language_defn *language;
 
@@ -222,12 +193,19 @@ struct linespec_state
   /* Canonical strings that mirror the std::vector<symtab_and_line> result.  */
   linespec_canonical_name *canonical_names = nullptr;
 
-  /* This is a set of address_entry objects which is used to prevent
-     duplicate symbols from being entered into the result.  */
-  htab_t addr_set;
-
   /* Are we building a linespec?  */
   int is_linespec = 0;
+
+private:
+
+  /* An address entry is used to ensure that any given location is
+     only added to the result a single time.  It holds an address and
+     the program space from which the address came.  */
+  using address_entry = std::pair<::program_space *, CORE_ADDR>;
+
+  /* This is a set of address_entry objects which is used to prevent
+     duplicate symbols from being entered into the result.  */
+  gdb::unordered_set<address_entry> addr_set;
 };
 
 /* This is a helper object that is used when collecting symbols into a
@@ -1139,29 +1117,6 @@ add_sal_to_sals (struct linespec_state *self,
     }
 }
 
-/* Check whether the address, represented by PSPACE and ADDR, is
-   already in the set.  If so, return 0.  Otherwise, add it and return
-   1.  */
-
-static int
-maybe_add_address (htab_t set, struct program_space *pspace, CORE_ADDR addr)
-{
-  struct address_entry e, *p;
-  void **slot;
-
-  e.pspace = pspace;
-  e.addr = addr;
-  slot = htab_find_slot (set, &e, INSERT);
-  if (*slot)
-    return 0;
-
-  p = XNEW (struct address_entry);
-  memcpy (p, &e, sizeof (struct address_entry));
-  *slot = p;
-
-  return 1;
-}
-
 /* A helper that walks over all matching symtabs in all objfiles and
    calls CALLBACK for each symbol matching NAME.  If SEARCH_PSPACE is
    not NULL, then the search is restricted to just that program
@@ -2243,7 +2198,7 @@ convert_linespec_to_sals (struct linespec_state *state, linespec *ls)
            = sym.symbol->symtab ()->compunit ()->objfile ()->pspace ();
 
          if (symbol_to_sal (&sal, state->funfirstline, sym.symbol)
-             && maybe_add_address (state->addr_set, pspace, sal.pc))
+             && state->maybe_add_address (pspace, sal.pc))
            add_sal_to_sals (state, &sals, &sal,
                             sym.symbol->natural_name (), 0);
        }
@@ -2308,7 +2263,7 @@ convert_linespec_to_sals (struct linespec_state *state, linespec *ls)
                {
                  symtab_and_line sal;
                  if (symbol_to_sal (&sal, state->funfirstline, sym.symbol)
-                     && maybe_add_address (state->addr_set, pspace, sal.pc))
+                     && state->maybe_add_address (pspace, sal.pc))
                    add_sal_to_sals (state, &sals, &sal,
                                     sym.symbol->natural_name (), 0);
                }
@@ -4157,7 +4112,7 @@ minsym_found (struct linespec_state *self, struct objfile *objfile,
 
   sal.section = msymbol->obj_section (objfile);
 
-  if (maybe_add_address (self->addr_set, objfile->pspace (), sal.pc))
+  if (self->maybe_add_address (objfile->pspace (), sal.pc))
     add_sal_to_sals (self, result, &sal, msymbol->natural_name (), 0);
 }