diff options
| -rw-r--r-- | gdb/ChangeLog | 5 | ||||
| -rw-r--r-- | gdb/dwarf2read.c | 21 |
2 files changed, 21 insertions, 5 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 4c8657c..01b66a1 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,10 @@ 2017-06-12 Pedro Alves <palves@redhat.com> + * dwarf2read.c (write_hash_table): Check if key already exists + before emplacing. + +2017-06-12 Pedro Alves <palves@redhat.com> + * dwarf2read.c (data_buf::append_space): Rename to... (data_buf::grow): ... this, and make private. Adjust all callers. (data_buf::append_uint): New method. diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c index 63a591e..93fd275 100644 --- a/gdb/dwarf2read.c +++ b/gdb/dwarf2read.c @@ -23430,11 +23430,22 @@ write_hash_table (mapped_symtab *symtab, data_buf &output, data_buf &cpool) if (it == NULL) continue; gdb_assert (it->index_offset == 0); - const auto insertpair - = symbol_hash_table.emplace (it->cu_indices, cpool.size ()); - it->index_offset = insertpair.first->second; - if (!insertpair.second) - continue; + + /* Finding before inserting is faster than always trying to + insert, because inserting always allocates a node, does the + lookup, and then destroys the new node if another node + already had the same key. C++17 try_emplace will avoid + this. */ + const auto found + = symbol_hash_table.find (it->cu_indices); + if (found != symbol_hash_table.end ()) + { + it->index_offset = found->second; + continue; + } + + symbol_hash_table.emplace (it->cu_indices, cpool.size ()); + it->index_offset = cpool.size (); cpool.append_data (MAYBE_SWAP (it->cu_indices.size ())); for (const auto iter : it->cu_indices) cpool.append_data (MAYBE_SWAP (iter)); |