Handle block-local names for Ada

GNAT can generate a mangled name with "B_N" (where N is a number) in
the middle, like "hello__B_1__fourth.0".  This is used for names local
to a block.  Multiple levels of block-local name can also occur, a
possibility that was neglected by v1 of this patch.  This patch
changes gdb to handle these names.

The wild name matcher is updated a straightforward way.  The full
matcher is rewritten.  The hash function is updated to ensure that
this works.

This version does not seem to have the performance problems that
affected v1.  In particular, the previously-slow "bt" problem has been
fixed.

gdb/ChangeLog
2020-12-14  Tom Tromey  <tromey@adacore.com>

	* dictionary.c (language_defn::search_name_hash): Ignore "B".
	* ada-lang.c (advance_wild_match): Ignore "B".
	(full_match): Remove.
	(do_full_match): Rewrite.

gdb/testsuite/ChangeLog
2020-12-14  Tom Tromey  <tromey@adacore.com>

	* gdb.ada/nested.exp: Add new tests.
	* gdb.ada/nested/hello.adb (Fourth, Fifth): New procedures.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 21a6b9730eb8bc214981021fc1936d7488d6a514..e15d6958cbf0c83cd63f4f2d44d6cf5869a55100 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,10 @@
+2020-12-14  Tom Tromey  <tromey@adacore.com>
+
+       * dictionary.c (language_defn::search_name_hash): Ignore "B".
+       * ada-lang.c (advance_wild_match): Ignore "B".
+       (full_match): Remove.
+       (do_full_match): Rewrite.
+
 2020-12-14  Tom Tromey  <tromey@adacore.com>
 
        * ada-lang.c (get_var_value): Only consider exact matches.

diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index ca66642dee02d039e360f912d3ffa4092f99153a..564cdbee13cec3fd6b3c85b4cdc0188c827053f1 100644 (file)
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -6037,6 +6037,13 @@ advance_wild_match (const char **namep, const char *name0, char target0)
              name += 2;
              break;
            }
+         else if (t1 == '_' && name[2] == 'B' && name[3] == '_')
+           {
+             /* Names like "pkg__B_N__name", where N is a number, are
+                block-local.  We can handle these by simply skipping
+                the "B_" here.  */
+             name += 4;
+           }
          else
            return 0;
        }
@@ -6081,28 +6088,6 @@ wild_match (const char *name, const char *patn)
     }
 }
 
-/* Returns true iff symbol name SYM_NAME matches SEARCH_NAME, ignoring
-   any trailing suffixes that encode debugging information or leading
-   _ada_ on SYM_NAME (see is_name_suffix commentary for the debugging
-   information that is ignored).  */
-
-static bool
-full_match (const char *sym_name, const char *search_name)
-{
-  size_t search_name_len = strlen (search_name);
-
-  if (strncmp (sym_name, search_name, search_name_len) == 0
-      && is_name_suffix (sym_name + search_name_len))
-    return true;
-
-  if (startswith (sym_name, "_ada_")
-      && strncmp (sym_name + 5, search_name, search_name_len) == 0
-      && is_name_suffix (sym_name + search_name_len + 5))
-    return true;
-
-  return false;
-}
-
 /* Add symbols from BLOCK matching LOOKUP_NAME in DOMAIN to vector
    *defn_symbols, updating the list of symbols in OBSTACKP (if
    necessary).  OBJFILE is the section containing BLOCK.  */
@@ -13606,7 +13591,41 @@ do_full_match (const char *symbol_search_name,
               const lookup_name_info &lookup_name,
               completion_match_result *comp_match_res)
 {
-  return full_match (symbol_search_name, ada_lookup_name (lookup_name));
+  if (startswith (symbol_search_name, "_ada_"))
+    symbol_search_name += 5;
+
+  const char *lname = lookup_name.ada ().lookup_name ().c_str ();
+  int uscore_count = 0;
+  while (*lname != '\0')
+    {
+      if (*symbol_search_name != *lname)
+       {
+         if (*symbol_search_name == 'B' && uscore_count == 2
+             && symbol_search_name[1] == '_')
+           {
+             symbol_search_name += 2;
+             while (isdigit (*symbol_search_name))
+               ++symbol_search_name;
+             if (symbol_search_name[0] == '_'
+                 && symbol_search_name[1] == '_')
+               {
+                 symbol_search_name += 2;
+                 continue;
+               }
+           }
+         return false;
+       }
+
+      if (*symbol_search_name == '_')
+       ++uscore_count;
+      else
+       uscore_count = 0;
+
+      ++symbol_search_name;
+      ++lname;
+    }
+
+  return is_name_suffix (symbol_search_name);
 }
 
 /* symbol_name_matcher_ftype for exact (verbatim) matches.  */

diff --git a/gdb/dictionary.c b/gdb/dictionary.c
index c94a49ee3737467e60275980eaa671ee7713b30a..d51f209e715740d21855d85c5c4538f13c1263c5 100644 (file)
--- a/gdb/dictionary.c
+++ b/gdb/dictionary.c
@@ -761,6 +761,13 @@ language_defn::search_name_hash (const char *string0) const
            {
              int c = string[2];
 
+             if (c == 'B' && string[3] == '_')
+               {
+                 for (string += 4; ISDIGIT (*string); ++string)
+                   ;
+                 continue;
+               }
+
              if ((c < 'a' || c > 'z') && c != 'O')
                return hash;
              hash = 0;

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index f0d452b7a3126340a52a8046fe9486c655b247c6..d5442f9a1d8c24267c75e2574dd6ec11cff80706 100644 (file)
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2020-12-14  Tom Tromey  <tromey@adacore.com>
+
+       * gdb.ada/nested.exp: Add new tests.
+       * gdb.ada/nested/hello.adb (Fourth, Fifth): New procedures.
+
 2020-12-14  Tom Tromey  <tromey@adacore.com>
 
        * gdb.dwarf2/ada-thick-pointer.exp: New file.

diff --git a/gdb/testsuite/gdb.ada/nested.exp b/gdb/testsuite/gdb.ada/nested.exp
index ea4bb4de35518c75069ff110f99eedbf2d9a4c2d..74f9f1f87aed9f3bde4beaeba78b9148acef6b05 100644 (file)
--- a/gdb/testsuite/gdb.ada/nested.exp
+++ b/gdb/testsuite/gdb.ada/nested.exp
@@ -34,3 +34,18 @@ gdb_test "break first" \
          "Breakpoint $any_nb at $any_addr: file .*hello.adb, line $any_nb." \
          "break on nested function First"
 
+gdb_test "break fourth" \
+    "Breakpoint $any_nb at $any_addr: file .*hello.adb, line $any_nb." \
+    "break on nested function fourth"
+
+gdb_test "break hello.fourth" \
+    "Breakpoint $any_nb at $any_addr: file .*hello.adb, line $any_nb." \
+    "full-qualified break on nested function fourth"
+
+gdb_test "break fifth" \
+    "Breakpoint $any_nb at $any_addr: file .*hello.adb, line $any_nb." \
+    "break on nested function fifth"
+
+gdb_test "break hello.fourth.fifth" \
+    "Breakpoint $any_nb at $any_addr: file .*hello.adb, line $any_nb." \
+    "full-qualified break on nested function fifth"

diff --git a/gdb/testsuite/gdb.ada/nested/hello.adb b/gdb/testsuite/gdb.ada/nested/hello.adb
index 2d1e532e47d4d72cc3fed8e98cd56fc8fb7ebabb..10ec6bf8201a8f714fd8a4a7e3d58df178c776c9 100644 (file)
--- a/gdb/testsuite/gdb.ada/nested/hello.adb
+++ b/gdb/testsuite/gdb.ada/nested/hello.adb
@@ -31,6 +31,20 @@ procedure Hello is
    end Third;
 
 begin
-   Third;
+   declare
+      procedure Fourth is
+      begin
+         Third;
+         declare
+            procedure Fifth is
+            begin
+               Second;
+            end Fifth;
+         begin
+            Fifth;
+         end;
+      end Fourth;
+   begin
+      Fourth;
+   end;
 end Hello;
-