diff mbox series

[v3,PR,symtab/30520,v2,1/4] gdb/symtab: check name matches before expanding a CU

Message ID 20240508202219.3584915-1-dmitry.neverov@jetbrains.com
State New
Headers
Series [v3,PR,symtab/30520,v2,1/4] gdb/symtab: check name matches before expanding a CU |

Checks

Context Check Description
linaro-tcwg-bot/tcwg_gdb_build--master-aarch64 success Testing passed
linaro-tcwg-bot/tcwg_gdb_build--master-arm success Testing passed
linaro-tcwg-bot/tcwg_gdb_check--master-arm success Testing passed
linaro-tcwg-bot/tcwg_gdb_check--master-aarch64 success Testing passed

Commit Message

Dmitry.Neverov May 8, 2024, 8:22 p.m. UTC 
  From: "Dmitry.Neverov" <dmitry.neverov@jetbrains.com>

The added check fixes the case when an unqualified lookup
name without template arguments causes expansion of many CUs
which contain the name with template arguments.

This is similar to what dw2_expand_symtabs_matching_symbol does
before expanding the CU.

In the referenced issue the lookup name was wxObjectDataPtr and many
CUs had names like wxObjectDataPtr<wxBitmapBundleImpl>. This caused
their expansion and the lookup took around a minute. The added check
helps to avoid the expansion and makes the symbol lookup to return in
a second or so.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30520
---
 gdb/dwarf2/read.c | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

Comments

Tom Tromey May 10, 2024, 6:39 p.m. UTC | #1 
>>>>> "Dmitry" == Dmitry Neverov <dmitry.neverov@jetbrains.com> writes:

Dmitry> From: "Dmitry.Neverov" <dmitry.neverov@jetbrains.com>
Dmitry> The added check fixes the case when an unqualified lookup
Dmitry> name without template arguments causes expansion of many CUs
Dmitry> which contain the name with template arguments.

These all look reasonable to me... what is the status of the copyright
assignment now?  I'm wondering if we can land them.

Tom
Tom Tromey May 17, 2024, 2:01 p.m. UTC | #2 
Dmitry> From: "Dmitry.Neverov" <dmitry.neverov@jetbrains.com>
Dmitry> The added check fixes the case when an unqualified lookup
Dmitry> name without template arguments causes expansion of many CUs
Dmitry> which contain the name with template arguments.

Tom> These all look reasonable to me... what is the status of the copyright
Tom> assignment now?  I'm wondering if we can land them.

This came through.  I'm going to apply the series in the name of
expediency; but Dmitry, if you plan to send more gdb patches, please
email me and I'll get you set up with write-after-approval access.

Tom
diff mbox series

Patch

diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
index 049ee4d52ff..16b9fd34522 100644
--- a/gdb/dwarf2/read.c
+++ b/gdb/dwarf2/read.c
@@ -16694,9 +16694,25 @@  cooked_index_functions::expand_symtabs_matching
 		= lookup_name_without_params.match_type ();
 	      if ((match_type == symbol_name_match_type::FULL
 		   || (lang != language_ada
-		       && match_type == symbol_name_match_type::EXPRESSION))
-		  && parent != nullptr)
-		continue;
+		       && match_type == symbol_name_match_type::EXPRESSION)))
+		{
+		  if (parent != nullptr)
+		    continue;
+
+		  if (entry->lang != language_unknown)
+		    {
+		      const language_defn *lang_def = language_def (entry->lang);
+		      lookup_name_info last_segment_lookup_name
+			(last_name.data (), symbol_name_match_type::FULL, false,
+			 true);
+		      symbol_name_matcher_ftype *name_matcher
+			= (lang_def->get_symbol_name_matcher
+			     (last_segment_lookup_name));
+		      if (!name_matcher (entry->canonical,
+					 last_segment_lookup_name, nullptr))
+			continue;
+		    }
+	      }
 	    }
 	  else
 	    {