#include <unordered_set>
#include <unordered_map>
#include "selftest.h"
+#include <cmath>
+#include <set>
+#include <forward_list>
+
+typedef struct symbol *symbolp;
+DEF_VEC_P (symbolp);
/* When == 1, print basic high level tracing messages.
When > 1, be more verbose.
}
/* The suffix for an index file. */
-#define INDEX_SUFFIX ".gdb-index"
+#define INDEX4_SUFFIX ".gdb-index"
+#define INDEX5_SUFFIX ".debug_names"
+#define DEBUG_STR_SUFFIX ".debug_str"
/* See declaration. */
\f
/* The "save gdb-index" command. */
+/* Write SIZE bytes from the buffer pointed to by DATA to FILE, with
+ error checking. */
+
+static void
+file_write (FILE *file, const void *data, size_t size)
+{
+ if (fwrite (data, 1, size, file) != size)
+ error (_("couldn't data write to file"));
+}
+
+/* Write the contents of VEC to FILE, with error checking. */
+
+template<typename Elem, typename Alloc>
+static void
+file_write (FILE *file, const std::vector<Elem, Alloc> &vec)
+{
+ file_write (file, vec.data (), vec.size () * sizeof (vec[0]));
+}
+
/* In-memory buffer to prepare data to be written later to a file. */
class data_buf
{
std::copy (cstr, cstr + size, grow (size));
}
+ /* Store INPUT as ULEB128 to the end of buffer. */
+ void append_unsigned_leb128 (ULONGEST input)
+ {
+ for (;;)
+ {
+ gdb_byte output = input & 0x7f;
+ input >>= 7;
+ if (input)
+ output |= 0x80;
+ append_data (output);
+ if (input == 0)
+ break;
+ }
+ }
+
/* Accept a host-format integer in VAL and append it to the buffer
as a target-format integer which is LEN bytes long. */
void append_uint (size_t len, bfd_endian byte_order, ULONGEST val)
return m_vec.size ();
}
+ /* Return true iff the buffer is empty. */
+ bool empty () const
+ {
+ return m_vec.empty ();
+ }
+
/* Write the buffer to FILE. */
void file_write (FILE *file) const
{
- if (::fwrite (m_vec.data (), 1, m_vec.size (), file) != m_vec.size ())
- error (_("couldn't write data to file"));
+ ::file_write (file, m_vec);
}
private:
return strcmp (m_cstr, other.m_cstr) == 0;
}
+ /* Return the underlying C string. Note, the returned string is
+ only a reference with lifetime of this object. */
+ const char *c_str () const
+ {
+ return m_cstr;
+ }
+
private:
friend class c_str_view_hasher;
const char *const m_cstr;
1);
}
-/* Create an index file for OBJFILE in the directory DIR. */
+/* Symbol name hashing function as specified by DWARF-5. */
-static void
-write_psymtabs_to_index (struct objfile *objfile, const char *dir)
+static uint32_t
+dwarf5_djb_hash (const char *str_)
{
- if (dwarf2_per_objfile->using_index)
- error (_("Cannot use an index to create the index"));
+ const unsigned char *str = (const unsigned char *) str_;
- if (VEC_length (dwarf2_section_info_def, dwarf2_per_objfile->types) > 1)
- error (_("Cannot make an index when the file has multiple .debug_types sections"));
+ /* Note: tolower here ignores UTF-8, which isn't fully compliant.
+ See http://dwarfstd.org/ShowIssue.php?issue=161027.1. */
- if (!objfile->psymtabs || !objfile->psymtabs_addrmap)
- return;
+ uint32_t hash = 5381;
+ while (int c = *str++)
+ hash = hash * 33 + tolower (c);
+ return hash;
+}
- struct stat st;
- if (stat (objfile_name (objfile), &st) < 0)
- perror_with_name (objfile_name (objfile));
+/* DWARF-5 .debug_names builder. */
+class debug_names
+{
+public:
+ debug_names (bool is_dwarf64, bfd_endian dwarf5_byte_order)
+ : m_dwarf5_byte_order (dwarf5_byte_order),
+ m_dwarf32 (dwarf5_byte_order),
+ m_dwarf64 (dwarf5_byte_order),
+ m_dwarf (is_dwarf64
+ ? static_cast<dwarf &> (m_dwarf64)
+ : static_cast<dwarf &> (m_dwarf32)),
+ m_name_table_string_offs (m_dwarf.name_table_string_offs),
+ m_name_table_entry_offs (m_dwarf.name_table_entry_offs)
+ {}
- std::string filename (std::string (dir) + SLASH_STRING
- + lbasename (objfile_name (objfile)) + INDEX_SUFFIX);
+ /* Insert one symbol. */
+ void insert (const partial_symbol *psym, int cu_index, bool is_static)
+ {
+ const int dwarf_tag = psymbol_tag (psym);
+ if (dwarf_tag == 0)
+ return;
+ const char *const name = SYMBOL_SEARCH_NAME (psym);
+ const auto insertpair
+ = m_name_to_value_set.emplace (c_str_view (name),
+ std::set<symbol_value> ());
+ std::set<symbol_value> &value_set = insertpair.first->second;
+ value_set.emplace (symbol_value (dwarf_tag, cu_index, is_static));
+ }
- FILE *out_file = gdb_fopen_cloexec (filename.c_str (), "wb").release ();
- if (!out_file)
- error (_("Can't open `%s' for writing"), filename.c_str ());
+ /* Build all the tables. All symbols must be already inserted.
+ This function does not call file_write, caller has to do it
+ afterwards. */
+ void build ()
+ {
+ /* Verify the build method has not be called twice. */
+ gdb_assert (m_abbrev_table.empty ());
+ const size_t name_count = m_name_to_value_set.size ();
+ m_bucket_table.resize
+ (std::pow (2, std::ceil (std::log2 (name_count * 4 / 3))));
+ m_hash_table.reserve (name_count);
+ m_name_table_string_offs.reserve (name_count);
+ m_name_table_entry_offs.reserve (name_count);
+
+ /* Map each hash of symbol to its name and value. */
+ struct hash_it_pair
+ {
+ uint32_t hash;
+ decltype (m_name_to_value_set)::const_iterator it;
+ };
+ std::vector<std::forward_list<hash_it_pair>> bucket_hash;
+ bucket_hash.resize (m_bucket_table.size ());
+ for (decltype (m_name_to_value_set)::const_iterator it
+ = m_name_to_value_set.cbegin ();
+ it != m_name_to_value_set.cend ();
+ ++it)
+ {
+ const char *const name = it->first.c_str ();
+ const uint32_t hash = dwarf5_djb_hash (name);
+ hash_it_pair hashitpair;
+ hashitpair.hash = hash;
+ hashitpair.it = it;
+ auto &slot = bucket_hash[hash % bucket_hash.size()];
+ slot.push_front (std::move (hashitpair));
+ }
+ for (size_t bucket_ix = 0; bucket_ix < bucket_hash.size (); ++bucket_ix)
+ {
+ const std::forward_list<hash_it_pair> &hashitlist
+ = bucket_hash[bucket_ix];
+ if (hashitlist.empty ())
+ continue;
+ uint32_t &bucket_slot = m_bucket_table[bucket_ix];
+ /* The hashes array is indexed starting at 1. */
+ store_unsigned_integer (reinterpret_cast<gdb_byte *> (&bucket_slot),
+ sizeof (bucket_slot), m_dwarf5_byte_order,
+ m_hash_table.size () + 1);
+ for (const hash_it_pair &hashitpair : hashitlist)
+ {
+ m_hash_table.push_back (0);
+ store_unsigned_integer (reinterpret_cast<gdb_byte *>
+ (&m_hash_table.back ()),
+ sizeof (m_hash_table.back ()),
+ m_dwarf5_byte_order, hashitpair.hash);
+ const c_str_view &name = hashitpair.it->first;
+ const std::set<symbol_value> &value_set = hashitpair.it->second;
+ m_name_table_string_offs.push_back_reorder
+ (m_debugstrlookup.lookup (name.c_str ()));
+ m_name_table_entry_offs.push_back_reorder (m_entry_pool.size ());
+ gdb_assert (!value_set.empty ());
+ for (const symbol_value &value : value_set)
+ {
+ int &idx = m_indexkey_to_idx[index_key (value.dwarf_tag,
+ value.is_static)];
+ if (idx == 0)
+ {
+ idx = m_idx_next++;
+ m_abbrev_table.append_unsigned_leb128 (idx);
+ m_abbrev_table.append_unsigned_leb128 (value.dwarf_tag);
+ m_abbrev_table.append_unsigned_leb128 (DW_IDX_compile_unit);
+ m_abbrev_table.append_unsigned_leb128 (DW_FORM_udata);
+ m_abbrev_table.append_unsigned_leb128 (value.is_static
+ ? DW_IDX_GNU_internal
+ : DW_IDX_GNU_external);
+ m_abbrev_table.append_unsigned_leb128 (DW_FORM_flag_present);
+
+ /* Terminate attributes list. */
+ m_abbrev_table.append_unsigned_leb128 (0);
+ m_abbrev_table.append_unsigned_leb128 (0);
+ }
- /* Order matters here; we want FILE to be closed before FILENAME is
- unlinked, because on MS-Windows one cannot delete a file that is
- still open. (Don't call anything here that might throw until
- file_closer is created.) */
- gdb::unlinker unlink_file (filename.c_str ());
- gdb_file_up close_out_file (out_file);
+ m_entry_pool.append_unsigned_leb128 (idx);
+ m_entry_pool.append_unsigned_leb128 (value.cu_index);
+ }
- mapped_symtab symtab;
- data_buf cu_list;
+ /* Terminate the list of CUs. */
+ m_entry_pool.append_unsigned_leb128 (0);
+ }
+ }
+ gdb_assert (m_hash_table.size () == name_count);
- /* While we're scanning CU's create a table that maps a psymtab pointer
- (which is what addrmap records) to its index (which is what is recorded
- in the index file). This will later be needed to write the address
- table. */
- psym_index_map cu_index_htab;
- cu_index_htab.reserve (dwarf2_per_objfile->n_comp_units);
+ /* Terminate tags list. */
+ m_abbrev_table.append_unsigned_leb128 (0);
+ }
- /* The CU list is already sorted, so we don't need to do additional
- work here. Also, the debug_types entries do not appear in
- all_comp_units, but only in their own hash table. */
+ /* Return .debug_names bucket count. This must be called only after
+ calling the build method. */
+ uint32_t bucket_count () const
+ {
+ /* Verify the build method has been already called. */
+ gdb_assert (!m_abbrev_table.empty ());
+ const uint32_t retval = m_bucket_table.size ();
+
+ /* Check for overflow. */
+ gdb_assert (retval == m_bucket_table.size ());
+ return retval;
+ }
+
+ /* Return .debug_names names count. This must be called only after
+ calling the build method. */
+ uint32_t name_count () const
+ {
+ /* Verify the build method has been already called. */
+ gdb_assert (!m_abbrev_table.empty ());
+ const uint32_t retval = m_hash_table.size ();
+
+ /* Check for overflow. */
+ gdb_assert (retval == m_hash_table.size ());
+ return retval;
+ }
+
+ /* Return number of bytes of .debug_names abbreviation table. This
+ must be called only after calling the build method. */
+ uint32_t abbrev_table_bytes () const
+ {
+ gdb_assert (!m_abbrev_table.empty ());
+ return m_abbrev_table.size ();
+ }
+
+ /* Recurse into all "included" dependencies and store their symbols
+ as if they appeared in this psymtab. */
+ void recursively_write_psymbols
+ (struct objfile *objfile,
+ struct partial_symtab *psymtab,
+ std::unordered_set<partial_symbol *> &psyms_seen,
+ int cu_index)
+ {
+ for (int i = 0; i < psymtab->number_of_dependencies; ++i)
+ if (psymtab->dependencies[i]->user != NULL)
+ recursively_write_psymbols (objfile, psymtab->dependencies[i],
+ psyms_seen, cu_index);
+
+ write_psymbols (psyms_seen,
+ &objfile->global_psymbols[psymtab->globals_offset],
+ psymtab->n_global_syms, cu_index, false);
+ write_psymbols (psyms_seen,
+ &objfile->static_psymbols[psymtab->statics_offset],
+ psymtab->n_static_syms, cu_index, true);
+ }
+
+ /* Return number of bytes the .debug_names section will have. This
+ must be called only after calling the build method. */
+ size_t bytes () const
+ {
+ /* Verify the build method has been already called. */
+ gdb_assert (!m_abbrev_table.empty ());
+ size_t expected_bytes = 0;
+ expected_bytes += m_bucket_table.size () * sizeof (m_bucket_table[0]);
+ expected_bytes += m_hash_table.size () * sizeof (m_hash_table[0]);
+ expected_bytes += m_name_table_string_offs.bytes ();
+ expected_bytes += m_name_table_entry_offs.bytes ();
+ expected_bytes += m_abbrev_table.size ();
+ expected_bytes += m_entry_pool.size ();
+ return expected_bytes;
+ }
+
+ /* Write .debug_names to FILE_NAMES and .debug_str addition to
+ FILE_STR. This must be called only after calling the build
+ method. */
+ void file_write (FILE *file_names, FILE *file_str) const
+ {
+ /* Verify the build method has been already called. */
+ gdb_assert (!m_abbrev_table.empty ());
+ ::file_write (file_names, m_bucket_table);
+ ::file_write (file_names, m_hash_table);
+ m_name_table_string_offs.file_write (file_names);
+ m_name_table_entry_offs.file_write (file_names);
+ m_abbrev_table.file_write (file_names);
+ m_entry_pool.file_write (file_names);
+ m_debugstrlookup.file_write (file_str);
+ }
+
+private:
+
+ /* Storage for symbol names mapping them to their .debug_str section
+ offsets. */
+ class debug_str_lookup
+ {
+ public:
+
+ /* Object costructor to be called for current DWARF2_PER_OBJFILE.
+ All .debug_str section strings are automatically stored. */
+ debug_str_lookup ()
+ : m_abfd (dwarf2_per_objfile->objfile->obfd)
+ {
+ dwarf2_read_section (dwarf2_per_objfile->objfile,
+ &dwarf2_per_objfile->str);
+ if (dwarf2_per_objfile->str.buffer == NULL)
+ return;
+ for (const gdb_byte *data = dwarf2_per_objfile->str.buffer;
+ data < (dwarf2_per_objfile->str.buffer
+ + dwarf2_per_objfile->str.size);)
+ {
+ const char *const s = reinterpret_cast<const char *> (data);
+ const auto insertpair
+ = m_str_table.emplace (c_str_view (s),
+ data - dwarf2_per_objfile->str.buffer);
+ if (!insertpair.second)
+ complaint (&symfile_complaints,
+ _("Duplicate string \"%s\" in "
+ ".debug_str section [in module %s]"),
+ s, bfd_get_filename (m_abfd));
+ data += strlen (s) + 1;
+ }
+ }
+
+ /* Return offset of symbol name S in the .debug_str section. Add
+ such symbol to the section's end if it does not exist there
+ yet. */
+ size_t lookup (const char *s)
+ {
+ const auto it = m_str_table.find (c_str_view (s));
+ if (it != m_str_table.end ())
+ return it->second;
+ const size_t offset = (dwarf2_per_objfile->str.size
+ + m_str_add_buf.size ());
+ m_str_table.emplace (c_str_view (s), offset);
+ m_str_add_buf.append_cstr0 (s);
+ return offset;
+ }
+
+ /* Append the end of the .debug_str section to FILE. */
+ void file_write (FILE *file) const
+ {
+ m_str_add_buf.file_write (file);
+ }
+
+ private:
+ std::unordered_map<c_str_view, size_t, c_str_view_hasher> m_str_table;
+ bfd *const m_abfd;
+
+ /* Data to add at the end of .debug_str for new needed symbol names. */
+ data_buf m_str_add_buf;
+ };
+
+ /* Container to map used DWARF tags to their .debug_names abbreviation
+ tags. */
+ class index_key
+ {
+ public:
+ index_key (int dwarf_tag_, bool is_static_)
+ : dwarf_tag (dwarf_tag_), is_static (is_static_)
+ {
+ }
+
+ bool
+ operator== (const index_key &other) const
+ {
+ return dwarf_tag == other.dwarf_tag && is_static == other.is_static;
+ }
+
+ const int dwarf_tag;
+ const bool is_static;
+ };
+
+ /* Provide std::unordered_map::hasher for index_key. */
+ class index_key_hasher
+ {
+ public:
+ size_t
+ operator () (const index_key &key) const
+ {
+ return (std::hash<int>() (key.dwarf_tag) << 1) | key.is_static;
+ }
+ };
+
+ /* Parameters of one symbol entry. */
+ class symbol_value
+ {
+ public:
+ const int dwarf_tag, cu_index;
+ const bool is_static;
+
+ symbol_value (int dwarf_tag_, int cu_index_, bool is_static_)
+ : dwarf_tag (dwarf_tag_), cu_index (cu_index_), is_static (is_static_)
+ {}
+
+ bool
+ operator< (const symbol_value &other) const
+ {
+#define X(n) \
+ do \
+ { \
+ if (n < other.n) \
+ return true; \
+ if (n > other.n) \
+ return false; \
+ } \
+ while (0)
+ X (dwarf_tag);
+ X (is_static);
+ X (cu_index);
+#undef X
+ return false;
+ }
+ };
+
+ /* Abstract base class to unify DWARF-32 and DWARF-64 name table
+ output. */
+ class offset_vec
+ {
+ protected:
+ const bfd_endian dwarf5_byte_order;
+ public:
+ explicit offset_vec (bfd_endian dwarf5_byte_order_)
+ : dwarf5_byte_order (dwarf5_byte_order_)
+ {}
+
+ /* Call std::vector::reserve for NELEM elements. */
+ virtual void reserve (size_t nelem) = 0;
+
+ /* Call std::vector::push_back with store_unsigned_integer byte
+ reordering for ELEM. */
+ virtual void push_back_reorder (size_t elem) = 0;
+
+ /* Return expected output size in bytes. */
+ virtual size_t bytes () const = 0;
+
+ /* Write name table to FILE. */
+ virtual void file_write (FILE *file) const = 0;
+ };
+
+ /* Template to unify DWARF-32 and DWARF-64 output. */
+ template<typename OffsetSize>
+ class offset_vec_tmpl : public offset_vec
+ {
+ public:
+ explicit offset_vec_tmpl (bfd_endian dwarf5_byte_order_)
+ : offset_vec (dwarf5_byte_order_)
+ {}
+
+ /* Implement offset_vec::reserve. */
+ void reserve (size_t nelem) override
+ {
+ m_vec.reserve (nelem);
+ }
+
+ /* Implement offset_vec::push_back_reorder. */
+ void push_back_reorder (size_t elem) override
+ {
+ m_vec.push_back (elem);
+ /* Check for overflow. */
+ gdb_assert (m_vec.back () == elem);
+ store_unsigned_integer (reinterpret_cast<gdb_byte *> (&m_vec.back ()),
+ sizeof (m_vec.back ()), dwarf5_byte_order, elem);
+ }
+
+ /* Implement offset_vec::bytes. */
+ size_t bytes () const override
+ {
+ return m_vec.size () * sizeof (m_vec[0]);
+ }
+
+ /* Implement offset_vec::file_write. */
+ void file_write (FILE *file) const override
+ {
+ ::file_write (file, m_vec);
+ }
+
+ private:
+ std::vector<OffsetSize> m_vec;
+ };
+
+ /* Base class to unify DWARF-32 and DWARF-64 .debug_names output
+ respecting name table width. */
+ class dwarf
+ {
+ public:
+ offset_vec &name_table_string_offs, &name_table_entry_offs;
+
+ dwarf (offset_vec &name_table_string_offs_,
+ offset_vec &name_table_entry_offs_)
+ : name_table_string_offs (name_table_string_offs_),
+ name_table_entry_offs (name_table_entry_offs_)
+ {
+ }
+ };
- /* The psyms_seen set is potentially going to be largish (~40k
- elements when indexing a -g3 build of GDB itself). Estimate the
- number of elements in order to avoid too many rehashes, which
- require rebuilding buckets and thus many trips to
- malloc/free. */
+ /* Template to unify DWARF-32 and DWARF-64 .debug_names output
+ respecting name table width. */
+ template<typename OffsetSize>
+ class dwarf_tmpl : public dwarf
+ {
+ public:
+ explicit dwarf_tmpl (bfd_endian dwarf5_byte_order_)
+ : dwarf (m_name_table_string_offs, m_name_table_entry_offs),
+ m_name_table_string_offs (dwarf5_byte_order_),
+ m_name_table_entry_offs (dwarf5_byte_order_)
+ {}
+
+ private:
+ offset_vec_tmpl<OffsetSize> m_name_table_string_offs;
+ offset_vec_tmpl<OffsetSize> m_name_table_entry_offs;
+ };
+
+ /* Try to reconstruct original DWARF tag for given partial_symbol.
+ This function is not DWARF-5 compliant but it is sufficient for
+ GDB as a DWARF-5 index consumer. */
+ static int psymbol_tag (const struct partial_symbol *psym)
+ {
+ domain_enum domain = PSYMBOL_DOMAIN (psym);
+ enum address_class aclass = PSYMBOL_CLASS (psym);
+
+ switch (domain)
+ {
+ case VAR_DOMAIN:
+ switch (aclass)
+ {
+ case LOC_BLOCK:
+ return DW_TAG_subprogram;
+ case LOC_TYPEDEF:
+ return DW_TAG_typedef;
+ case LOC_COMPUTED:
+ case LOC_CONST_BYTES:
+ case LOC_OPTIMIZED_OUT:
+ case LOC_STATIC:
+ return DW_TAG_variable;
+ case LOC_CONST:
+ /* Note: It's currently impossible to recognize psyms as enum values
+ short of reading the type info. For now punt. */
+ return DW_TAG_variable;
+ default:
+ /* There are other LOC_FOO values that one might want to classify
+ as variables, but dwarf2read.c doesn't currently use them. */
+ return DW_TAG_variable;
+ }
+ case STRUCT_DOMAIN:
+ return DW_TAG_structure_type;
+ default:
+ return 0;
+ }
+ }
+
+ /* Call insert for all partial symbols and mark them in PSYMS_SEEN. */
+ void write_psymbols (std::unordered_set<partial_symbol *> &psyms_seen,
+ struct partial_symbol **psymp, int count, int cu_index,
+ bool is_static)
+ {
+ for (; count-- > 0; ++psymp)
+ {
+ struct partial_symbol *psym = *psymp;
+
+ if (SYMBOL_LANGUAGE (psym) == language_ada)
+ error (_("Ada is not currently supported by the index"));
+
+ /* Only add a given psymbol once. */
+ if (psyms_seen.insert (psym).second)
+ insert (psym, cu_index, is_static);
+ }
+ }
+
+ /* Store value of each symbol. */
+ std::unordered_map<c_str_view, std::set<symbol_value>, c_str_view_hasher>
+ m_name_to_value_set;
+
+ /* Tables of DWARF-5 .debug_names. They are in object file byte
+ order. */
+ std::vector<uint32_t> m_bucket_table;
+ std::vector<uint32_t> m_hash_table;
+
+ const bfd_endian m_dwarf5_byte_order;
+ dwarf_tmpl<uint32_t> m_dwarf32;
+ dwarf_tmpl<uint64_t> m_dwarf64;
+ dwarf &m_dwarf;
+ offset_vec &m_name_table_string_offs, &m_name_table_entry_offs;
+ debug_str_lookup m_debugstrlookup;
+
+ /* Map each used .debug_names abbreviation tag parameter to its
+ index value. */
+ std::unordered_map<index_key, int, index_key_hasher> m_indexkey_to_idx;
+
+ /* Next unused .debug_names abbreviation tag for
+ m_indexkey_to_idx. */
+ int m_idx_next = 1;
+
+ /* .debug_names abbreviation table. */
+ data_buf m_abbrev_table;
+
+ /* .debug_names entry pool. */
+ data_buf m_entry_pool;
+};
+
+/* Return iff any of the needed offsets does not fit into 32-bit
+ .debug_names section. */
+
+static bool
+check_dwarf64_offsets ()
+{
+ for (int i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
+ {
+ const dwarf2_per_cu_data &per_cu = *dwarf2_per_objfile->all_comp_units[i];
+
+ if (to_underlying (per_cu.sect_off) >= (static_cast<uint64_t> (1) << 32))
+ return true;
+ }
+ for (int i = 0; i < dwarf2_per_objfile->n_type_units; ++i)
+ {
+ const signatured_type &sigtype = *dwarf2_per_objfile->all_type_units[i];
+ const dwarf2_per_cu_data &per_cu = sigtype.per_cu;
+
+ if (to_underlying (per_cu.sect_off) >= (static_cast<uint64_t> (1) << 32))
+ return true;
+ }
+ return false;
+}
+
+/* The psyms_seen set is potentially going to be largish (~40k
+ elements when indexing a -g3 build of GDB itself). Estimate the
+ number of elements in order to avoid too many rehashes, which
+ require rebuilding buckets and thus many trips to
+ malloc/free. */
+
+static size_t
+psyms_seen_size ()
+{
size_t psyms_count = 0;
for (int i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
{
}
/* Generating an index for gdb itself shows a ratio of
TOTAL_SEEN_SYMS/UNIQUE_SYMS or ~5. 4 seems like a good bet. */
- std::unordered_set<partial_symbol *> psyms_seen (psyms_count / 4);
+ return psyms_count / 4;
+}
+
+/* Write new .gdb_index section for OBJFILE into OUT_FILE.
+ Return how many bytes were expected to be written into OUT_FILE. */
+
+static size_t
+write_gdbindex (struct objfile *objfile, FILE *out_file)
+{
+ mapped_symtab symtab;
+ data_buf cu_list;
+
+ /* While we're scanning CU's create a table that maps a psymtab pointer
+ (which is what addrmap records) to its index (which is what is recorded
+ in the index file). This will later be needed to write the address
+ table. */
+ psym_index_map cu_index_htab;
+ cu_index_htab.reserve (dwarf2_per_objfile->n_comp_units);
+
+ /* The CU list is already sorted, so we don't need to do additional
+ work here. Also, the debug_types entries do not appear in
+ all_comp_units, but only in their own hash table. */
+
+ std::unordered_set<partial_symbol *> psyms_seen (psyms_seen_size ());
for (int i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
{
struct dwarf2_per_cu_data *per_cu
symtab_vec.file_write (out_file);
constant_pool.file_write (out_file);
+ return total_len;
+}
+
+/* DWARF-5 augmentation string for GDB's DW_IDX_GNU_* extension. */
+static const gdb_byte dwarf5_gdb_augmentation[] = { 'G', 'D', 'B', 0 };
+
+/* Write a new .debug_names section for OBJFILE into OUT_FILE, write
+ needed addition to .debug_str section to OUT_FILE_STR. Return how
+ many bytes were expected to be written into OUT_FILE. */
+
+static size_t
+write_debug_names (struct objfile *objfile, FILE *out_file, FILE *out_file_str)
+{
+ const bool dwarf5_is_dwarf64 = check_dwarf64_offsets ();
+ const int dwarf5_offset_size = dwarf5_is_dwarf64 ? 8 : 4;
+ const enum bfd_endian dwarf5_byte_order
+ = gdbarch_byte_order (get_objfile_arch (objfile));
+
+ /* The CU list is already sorted, so we don't need to do additional
+ work here. Also, the debug_types entries do not appear in
+ all_comp_units, but only in their own hash table. */
+ data_buf cu_list;
+ debug_names nametable (dwarf5_is_dwarf64, dwarf5_byte_order);
+ std::unordered_set<partial_symbol *> psyms_seen (psyms_seen_size ());
+ for (int i = 0; i < dwarf2_per_objfile->n_comp_units; ++i)
+ {
+ const dwarf2_per_cu_data *per_cu = dwarf2_per_objfile->all_comp_units[i];
+ partial_symtab *psymtab = per_cu->v.psymtab;
+
+ /* CU of a shared file from 'dwz -m' may be unused by this main
+ file. It may be referenced from a local scope but in such
+ case it does not need to be present in .debug_names. */
+ if (psymtab == NULL)
+ continue;
+
+ if (psymtab->user == NULL)
+ nametable.recursively_write_psymbols (objfile, psymtab, psyms_seen, i);
+
+ cu_list.append_uint (dwarf5_offset_size, dwarf5_byte_order,
+ to_underlying (per_cu->sect_off));
+ }
+ nametable.build ();
+
+ /* No addr_vec - DWARF-5 uses .debug_aranges generated by GCC. */
+
+ data_buf types_cu_list;
+ for (int i = 0; i < dwarf2_per_objfile->n_type_units; ++i)
+ {
+ const signatured_type &sigtype = *dwarf2_per_objfile->all_type_units[i];
+ const dwarf2_per_cu_data &per_cu = sigtype.per_cu;
+
+ types_cu_list.append_uint (dwarf5_offset_size, dwarf5_byte_order,
+ to_underlying (per_cu.sect_off));
+ }
+
+ const offset_type bytes_of_header
+ = ((dwarf5_is_dwarf64 ? 12 : 4)
+ + 2 + 2 + 7 * 4
+ + sizeof (dwarf5_gdb_augmentation));
+ size_t expected_bytes = 0;
+ expected_bytes += bytes_of_header;
+ expected_bytes += cu_list.size ();
+ expected_bytes += types_cu_list.size ();
+ expected_bytes += nametable.bytes ();
+ data_buf header;
+
+ if (!dwarf5_is_dwarf64)
+ {
+ const uint64_t size64 = expected_bytes - 4;
+ gdb_assert (size64 < 0xfffffff0);
+ header.append_uint (4, dwarf5_byte_order, size64);
+ }
+ else
+ {
+ header.append_uint (4, dwarf5_byte_order, 0xffffffff);
+ header.append_uint (8, dwarf5_byte_order, expected_bytes - 12);
+ }
+
+ /* The version number. */
+ header.append_uint (2, dwarf5_byte_order, 5);
+
+ /* Padding. */
+ header.append_uint (2, dwarf5_byte_order, 0);
+
+ /* comp_unit_count - The number of CUs in the CU list. */
+ header.append_uint (4, dwarf5_byte_order, dwarf2_per_objfile->n_comp_units);
+
+ /* local_type_unit_count - The number of TUs in the local TU
+ list. */
+ header.append_uint (4, dwarf5_byte_order, dwarf2_per_objfile->n_type_units);
+
+ /* foreign_type_unit_count - The number of TUs in the foreign TU
+ list. */
+ header.append_uint (4, dwarf5_byte_order, 0);
+
+ /* bucket_count - The number of hash buckets in the hash lookup
+ table. */
+ header.append_uint (4, dwarf5_byte_order, nametable.bucket_count ());
+
+ /* name_count - The number of unique names in the index. */
+ header.append_uint (4, dwarf5_byte_order, nametable.name_count ());
+
+ /* abbrev_table_size - The size in bytes of the abbreviations
+ table. */
+ header.append_uint (4, dwarf5_byte_order, nametable.abbrev_table_bytes ());
+
+ /* augmentation_string_size - The size in bytes of the augmentation
+ string. This value is rounded up to a multiple of 4. */
+ static_assert (sizeof (dwarf5_gdb_augmentation) % 4 == 0, "");
+ header.append_uint (4, dwarf5_byte_order, sizeof (dwarf5_gdb_augmentation));
+ header.append_data (dwarf5_gdb_augmentation);
+
+ gdb_assert (header.size () == bytes_of_header);
+
+ header.file_write (out_file);
+ cu_list.file_write (out_file);
+ types_cu_list.file_write (out_file);
+ nametable.file_write (out_file, out_file_str);
+
+ return expected_bytes;
+}
+
+/* Assert that FILE's size is EXPECTED_SIZE. Assumes file's seek
+ position is at the end of the file. */
+
+static void
+assert_file_size (FILE *file, const char *filename, size_t expected_size)
+{
+ const auto file_size = ftell (file);
+ if (file_size == -1)
+ error (_("Can't get `%s' size"), filename);
+ gdb_assert (file_size == expected_size);
+}
+
+/* An index variant. */
+enum dw_index_kind
+{
+ /* GDB's own .gdb_index format. */
+ GDB_INDEX,
+
+ /* DWARF5 .debug_names. */
+ DEBUG_NAMES,
+};
+
+/* Create an index file for OBJFILE in the directory DIR. */
+
+static void
+write_psymtabs_to_index (struct objfile *objfile, const char *dir,
+ dw_index_kind index_kind)
+{
+ if (dwarf2_per_objfile->using_index)
+ error (_("Cannot use an index to create the index"));
+
+ if (VEC_length (dwarf2_section_info_def, dwarf2_per_objfile->types) > 1)
+ error (_("Cannot make an index when the file has multiple .debug_types sections"));
+
+ if (!objfile->psymtabs || !objfile->psymtabs_addrmap)
+ return;
+
+ struct stat st;
+ if (stat (objfile_name (objfile), &st) < 0)
+ perror_with_name (objfile_name (objfile));
+
+ std::string filename (std::string (dir) + SLASH_STRING
+ + lbasename (objfile_name (objfile))
+ + (index_kind == dw_index_kind::DEBUG_NAMES
+ ? INDEX5_SUFFIX : INDEX4_SUFFIX));
+
+ FILE *out_file = gdb_fopen_cloexec (filename.c_str (), "wb").release ();
+ if (!out_file)
+ error (_("Can't open `%s' for writing"), filename.c_str ());
+
+ /* Order matters here; we want FILE to be closed before FILENAME is
+ unlinked, because on MS-Windows one cannot delete a file that is
+ still open. (Don't call anything here that might throw until
+ file_closer is created.) */
+ gdb::unlinker unlink_file (filename.c_str ());
+ gdb_file_up close_out_file (out_file);
+
+ if (index_kind == dw_index_kind::DEBUG_NAMES)
+ {
+ std::string filename_str (std::string (dir) + SLASH_STRING
+ + lbasename (objfile_name (objfile))
+ + DEBUG_STR_SUFFIX);
+ FILE *out_file_str
+ = gdb_fopen_cloexec (filename_str.c_str (), "wb").release ();
+ if (!out_file_str)
+ error (_("Can't open `%s' for writing"), filename_str.c_str ());
+ gdb::unlinker unlink_file_str (filename_str.c_str ());
+ gdb_file_up close_out_file_str (out_file_str);
+
+ const size_t total_len
+ = write_debug_names (objfile, out_file, out_file_str);
+ assert_file_size (out_file, filename.c_str (), total_len);
+
+ /* We want to keep the file .debug_str file too. */
+ unlink_file_str.keep ();
+ }
+ else
+ {
+ const size_t total_len
+ = write_gdbindex (objfile, out_file);
+ assert_file_size (out_file, filename.c_str (), total_len);
+ }
+
/* We want to keep the file. */
unlink_file.keep ();
}
/* Implementation of the `save gdb-index' command.
- Note that the file format used by this command is documented in the
- GDB manual. Any changes here must be documented there. */
+ Note that the .gdb_index file format used by this command is
+ documented in the GDB manual. Any changes here must be documented
+ there. */
static void
save_gdb_index_command (const char *arg, int from_tty)
{
struct objfile *objfile;
+ const char dwarf5space[] = "-dwarf-5 ";
+ dw_index_kind index_kind = dw_index_kind::GDB_INDEX;
+
+ if (!arg)
+ arg = "";
+
+ arg = skip_spaces (arg);
+ if (strncmp (arg, dwarf5space, strlen (dwarf5space)) == 0)
+ {
+ index_kind = dw_index_kind::DEBUG_NAMES;
+ arg += strlen (dwarf5space);
+ arg = skip_spaces (arg);
+ }
- if (!arg || !*arg)
- error (_("usage: save gdb-index DIRECTORY"));
+ if (!*arg)
+ error (_("usage: save gdb-index [-dwarf-5] DIRECTORY"));
ALL_OBJFILES (objfile)
{
TRY
{
- write_psymtabs_to_index (objfile, arg);
+ write_psymtabs_to_index (objfile, arg, index_kind);
}
CATCH (except, RETURN_MASK_ERROR)
{
c = add_cmd ("gdb-index", class_files, save_gdb_index_command,
_("\
Save a gdb-index file.\n\
-Usage: save gdb-index DIRECTORY"),
+Usage: save gdb-index [-dwarf-5] DIRECTORY\n\
+\n\
+No options create one file with .gdb-index extension for pre-DWARF-5\n\
+compatible .gdb_index section. With -dwarf-5 creates two files with\n\
+extension .debug_names and .debug_str for DWARF-5 .debug_names section."),
&save_cmdlist);
set_cmd_completer (c, filename_completer);
projects / binutils-gdb.git / commitdiff