Commit Graph

6 Commits

Author SHA1 Message Date
Greg Clayton d4a2b37091 Huge memory and performance improvements in the DWARF parser.
Address ranges are now split up into two different tables: 
- one in DWARFDebugInfo that is compile unit specific
- one in each DWARFCompileUnit that has exact function DIE offsets

This helps keep the size of the aranges down since the main table will get
uniqued and sorted and have consecutive ranges merged. We then only parse the
compile unit one on demand once we have determined that a compile unit contains
the address in question. We also now use the .debug_aranges section if there 
is one instead of always indexing the DWARF manually.

NameToDIE now uses a UniqueCStringMap<dw_offset> map instead of a std::map.
std::map is very bulky as each node has 3 pointers and the key and value types.
This gets our NameToDIE entry down to 12 bytes each instead of 48 which saves
us a lot of memory when we have very large DWARF.

DWARFDebugAranges now has a smaller footprint for each range it contains to 
save on memory.

llvm-svn: 139557
2011-09-12 23:21:58 +00:00
Greg Clayton afacd14b0b Added the ability for DWARF locations to use the ABI plug-ins to resolve
register names when dumping variable locations and location lists. Also did
some cleanup where "int" types were being used for "lldb::RegisterKind"
values.

llvm-svn: 138988
2011-09-02 01:15:17 +00:00
Greg Clayton f9eec20bd3 Added support for accessing and loading our new .debug_names and .debug_types
DWARF accelerator table sections to the DWARF parser. These sections are similar
to the .debug_pubnames and .debug_pubtypes, but they are designed to be hash tables
that are saved to disc in a way that the sections can just be loaded into memory
and used without any work on the debugger side. The .debug_pubnames and .debug_pubtypes
sections are not ordered, contain a copy of the name in the section itself which
makes these sections quite large, they only include publicly exported names (so no
static functions, no types defined inside functions), many compilers put different
information in them making them very unreliable so most debugger ignore these sections
and parse the DWARF on their own. The tables must also be parsed and sorted in order 
to be used effectively. The new sections can be quickly loaded and very efficiently be used 
to do name to DIE lookups with very little up front work. The format of these new
sections will be changing while we work out the bugs, but we hope to have really 
fast name to DIE lookups soon.

llvm-svn: 138979
2011-09-01 23:16:13 +00:00
Greg Clayton 05562d1e5c Added code to test hash bucket sizes for an DWARF index that we can write
to a file.

llvm-svn: 138620
2011-08-26 02:44:58 +00:00
Greg Clayton b677cb893d Header file cleanup and moved an inline to the implementation file.
llvm-svn: 132828
2011-06-10 01:37:29 +00:00
Greg Clayton c685f8e540 So we can't use .debug_pubtypes as it, as designed, does not tell us about
all types in all compile units. I added a new kind of accelerator table to
the DWARF that allows us to index the DWARF compile units and DIEs in a way
that doesn't require the data to stay loaded. Currently when indexing the
DWARF we check if the compile unit had parsed its DIEs and if it hasn't we
index the data and free all of the DIEs so we can reparse later when we need
to after using one of our complete accelerator tables to determine we need
to reparse some DWARF. If the DIEs had already been parsed we leave them 
loaded. The new accelerator table uses the "const char *" pointers from our
ConstString class as the keys, and NameToDIE::Info as the value. This info
contains the compile unit index and the DIE index which means we are pointed
right to the DIE we need unlike the other DWARF accelerator tables that often
just point us to the compile unit we would find our answer in. 

llvm-svn: 113933
2010-09-15 04:15:46 +00:00