Convert linespec.c to new hash table

This converts linespec.c to use the new hash table.

Note that more simplification could perhaps be done.  Currently, the
collectors in this code insert an element into a set and then, if the
element has not been seen before, append it to a vector.  If we know
the order does not matter, or if the results can be sorted later, we
could dispense with the vector.  This would simplify the code some
more.  (This technique is used in the vtable patch, later in this
series.)

Change-Id: Ie6828b1520d918d189ab5140dc8094a609152cf2
Co-Authored-By: Tom Tromey <tom@tromey.com>
Approved-By: Tom Tromey <tom@tromey.com>

1 files changed, 18 insertions, 36 deletions

diff --git a/gdb/linespec.c b/gdb/linespec.c
index 528abc46b89..d70008778e2 100644
--- a/gdb/linespec.c
+++ b/gdb/linespec.c
@@ -45,6 +45,7 @@
 #include "gdbsupport/def-vector.h"
 #include <algorithm>
 #include "inferior.h"
+#include "gdbsupport/unordered_set.h"
 
 /* An enumeration of the various things a user might attempt to
    complete for a linespec location.  */
@@ -3400,12 +3401,9 @@ namespace {
 class decode_compound_collector
 {
 public:
-  decode_compound_collector ()
-    : m_unique_syms (htab_create_alloc (1, htab_hash_pointer,
-					htab_eq_pointer, NULL,
-					xcalloc, xfree))
-  {
-  }
+  decode_compound_collector () = default;
+
+  DISABLE_COPY_AND_ASSIGN (decode_compound_collector);
 
   /* Return all symbols collected.  */
   std::vector<block_symbol> release_symbols ()
@@ -3419,7 +3417,7 @@ public:
 private:
   /* A hash table of all symbols we found.  We use this to avoid
      adding any symbol more than once.  */
-  htab_up m_unique_syms;
+  gdb::unordered_set<const symbol *> m_unique_syms;
 
   /* The result vector.  */
   std::vector<block_symbol>  m_symbols;
@@ -3428,7 +3426,6 @@ private:
 bool
 decode_compound_collector::operator () (block_symbol *bsym)
 {
-  void **slot;
   struct type *t;
   struct symbol *sym = bsym->symbol;
 
@@ -3442,12 +3439,8 @@ decode_compound_collector::operator () (block_symbol *bsym)
       && t->code () != TYPE_CODE_NAMESPACE)
     return true; /* Continue iterating.  */
 
-  slot = htab_find_slot (m_unique_syms.get (), sym, INSERT);
-  if (!*slot)
-    {
-      *slot = sym;
-      m_symbols.push_back (*bsym);
-    }
+  if (m_unique_syms.insert (sym).second)
+    m_symbols.push_back (*bsym);
 
   return true; /* Continue iterating.  */
 }
@@ -3671,14 +3664,18 @@ namespace {
 class symtab_collector
 {
 public:
-  symtab_collector ()
-    : m_symtab_table (htab_create (1, htab_hash_pointer, htab_eq_pointer,
-				   NULL))
-  {
-  }
+  symtab_collector () = default;
+
+  DISABLE_COPY_AND_ASSIGN (symtab_collector);
 
   /* Callable as a symbol_found_callback_ftype callback.  */
-  bool operator () (symtab *sym);
+  bool operator () (struct symtab *symtab)
+  {
+    if (m_symtab_table.insert (symtab).second)
+      m_symtabs.push_back (symtab);
+
+    return false;
+  }
 
   /* Return an rvalue reference to the collected symtabs.  */
   std::vector<symtab *> &&release_symtabs ()
@@ -3691,24 +3688,9 @@ private:
   std::vector<symtab *> m_symtabs;
 
   /* This is used to ensure the symtabs are unique.  */
-  htab_up m_symtab_table;
+  gdb::unordered_set<const symtab *> m_symtab_table;
 };
 
-bool
-symtab_collector::operator () (struct symtab *symtab)
-{
-  void **slot;
-
-  slot = htab_find_slot (m_symtab_table.get (), symtab, INSERT);
-  if (!*slot)
-    {
-      *slot = symtab;
-      m_symtabs.push_back (symtab);
-    }
-
-  return false;
-}
-
 } // namespace
 
 /* Given a file name, return a list of all matching symtabs.  If