[Lldb-commits] [lldb] r145086 - in /lldb/trunk/source/Plugins/SymbolFile/DWARF: DWARFCompileUnit.cpp DWARFCompileUnit.h DWARFDebugInfoEntry.cpp

[Greg Clayton]

Author: gclayton
Date: Tue Nov 22 15:35:27 2011
New Revision: 145086

URL: http://llvm.org/viewvc/llvm-project?rev=145086&view=rev
Log:
Shrink-to-fit our std::vector<DWARFDebugInfoEntry> collections and save 20%
to 30% of memory. The size doubling was killing us and we ended up with up to
just under 50% of empty capacity. Cleaning this up saves us a ton of memory.



Modified:
    lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.cpp
    lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.h
    lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp

Modified: lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.cpp
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.cpp?rev=145086&r1=145085&r2=145086&view=diff
==============================================================================
--- lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.cpp (original)
+++ lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.cpp Tue Nov 22 15:35:27 2011
@@ -271,7 +271,17 @@
         }
         fprintf (stderr, "warning: DWARF compile unit extends beyond its bounds cu 0x%8.8x at 0x%8.8x in '%s'\n", GetOffset(), offset, path);
     }
+
+    // Since std::vector objects will double their size, we really need to
+    // make a new array with the perfect size so we don't end up wasting
+    // space. So here we copy and swap to make sure we don't have any extra
+    // memory taken up.
     
+    if (m_die_array.size () < m_die_array.capacity())
+    {
+        DWARFDebugInfoEntry::collection exact_size_die_array (m_die_array.begin(), m_die_array.end());
+        exact_size_die_array.swap (m_die_array);
+    }
     LogSP log (LogChannelDWARF::GetLogIfAll (DWARF_LOG_DEBUG_INFO));
     if (log)
     {

Modified: lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.h
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.h?rev=145086&r1=145085&r2=145086&view=diff
==============================================================================
--- lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.h (original)
+++ lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFCompileUnit.h Tue Nov 22 15:35:27 2011
@@ -74,13 +74,11 @@
     }
 
     void
-    AddDIE(DWARFDebugInfoEntry& die)
+    AddDIE (DWARFDebugInfoEntry& die)
     {
         // The average bytes per DIE entry has been seen to be
-        // around 14-20 so lets pre-reserve the needed memory for
-        // our DIE entries accordingly. Search forward for "Compute
-        // average bytes per DIE" to see #if'ed out code that does
-        // that determination.
+        // around 14-20 so lets pre-reserve half of that since
+        // we are now stripping the NULL tags. 
 
         // Only reserve the memory if we are adding children of
         // the main compile unit DIE. The compile unit DIE is always
@@ -88,7 +86,7 @@
         // the first compile unit child DIE and should reserve
         // the memory.
         if (m_die_array.empty())
-            m_die_array.reserve(GetDebugInfoSize() / 14);
+            m_die_array.reserve(GetDebugInfoSize() / 24);
         m_die_array.push_back(die);
     }
 

Modified: lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp?rev=145086&r1=145085&r2=145086&view=diff
==============================================================================
--- lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp (original)
+++ lldb/trunk/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp Tue Nov 22 15:35:27 2011
@@ -1926,8 +1926,8 @@
 {
     DWARFDebugInfoEntry::const_iterator pos;
     DWARFDebugInfoEntry::const_iterator end = die_collection.end();
-    puts("offset    parent   sibling  child");
-    puts("--------  -------- -------- --------");
+    strm.PutCString("\noffset    parent   sibling  child\n");
+    strm.PutCString("--------  -------- -------- --------\n");
     for (pos = die_collection.begin(); pos != end; ++pos)
     {
         const DWARFDebugInfoEntry& die_ref = *pos;