[Lldb-commits] [lldb] 13278ef - [lldb] Remove some trivial scoped timers

[Dave Lee via lldb-commits]

Author: Dave Lee
Date: 2021-12-06T15:22:28-08:00
New Revision: 13278efd0c95a8b589bbd7dbbf17680a03b6eb77

URL: https://github.com/llvm/llvm-project/commit/13278efd0c95a8b589bbd7dbbf17680a03b6eb77
DIFF: https://github.com/llvm/llvm-project/commit/13278efd0c95a8b589bbd7dbbf17680a03b6eb77.diff

LOG: [lldb] Remove some trivial scoped timers

While profiling lldb (from swift/llvm-project), these timers were noticed to be short lived and high firing, and so they add noise more than value.

The data points I recorded are:

`FindTypes_Impl`: 49,646 calls, 812ns avg, 40.33ms total
`AppendSymbolIndexesWithName`: 36,229 calls, 913ns avg, 33.09ms total
`FindAllSymbolsWithNameAndType`: 36,229 calls, 1.93µs avg, 70.05ms total
`FindSymbolsWithNameAndType`: 23,263 calls, 3.09µs avg, 71.88ms total

Differential Revision: https://reviews.llvm.org/D115182

Added: 
    

Modified: 
    lldb/source/Core/Module.cpp
    lldb/source/Symbol/Symtab.cpp

Removed: 
    


################################################################################
diff  --git a/lldb/source/Core/Module.cpp b/lldb/source/Core/Module.cpp
index cbecbb9aa5fed..dbec8250223cf 100644
--- a/lldb/source/Core/Module.cpp
+++ b/lldb/source/Core/Module.cpp
@@ -940,7 +940,6 @@ void Module::FindTypes_Impl(
     size_t max_matches,
     llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files,
     TypeMap &types) {
-  LLDB_SCOPED_TIMER();
   if (SymbolFile *symbols = GetSymbolFile())
     symbols->FindTypes(name, parent_decl_ctx, max_matches,
                        searched_symbol_files, types);
@@ -1346,9 +1345,6 @@ void Module::FindSymbolsWithNameAndType(ConstString name,
                                           SymbolContextList &sc_list) {
   // No need to protect this call using m_mutex all other method calls are
   // already thread safe.
-  LLDB_SCOPED_TIMERF(
-      "Module::FindSymbolsWithNameAndType (name = %s, type = %i)",
-      name.AsCString(), symbol_type);
   if (Symtab *symtab = GetSymtab()) {
     std::vector<uint32_t> symbol_indexes;
     symtab->FindAllSymbolsWithNameAndType(name, symbol_type, symbol_indexes);

diff  --git a/lldb/source/Symbol/Symtab.cpp b/lldb/source/Symbol/Symtab.cpp
index c67955523bfb1..0057b9e6c8fb2 100644
--- a/lldb/source/Symbol/Symtab.cpp
+++ b/lldb/source/Symbol/Symtab.cpp
@@ -663,7 +663,6 @@ uint32_t Symtab::AppendSymbolIndexesWithName(ConstString symbol_name,
                                              std::vector<uint32_t> &indexes) {
   std::lock_guard<std::recursive_mutex> guard(m_mutex);
 
-  LLDB_SCOPED_TIMER();
   if (symbol_name) {
     if (!m_name_indexes_computed)
       InitNameIndexes();
@@ -808,7 +807,6 @@ Symtab::FindAllSymbolsWithNameAndType(ConstString name,
                                       std::vector<uint32_t> &symbol_indexes) {
   std::lock_guard<std::recursive_mutex> guard(m_mutex);
 
-  LLDB_SCOPED_TIMER();
   // Initialize all of the lookup by name indexes before converting NAME to a
   // uniqued string NAME_STR below.
   if (!m_name_indexes_computed)