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-rw-r--r--gdb/dwarf2read.c73
1 files changed, 4 insertions, 69 deletions
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 032fbd5..a5889ed 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -16005,75 +16005,10 @@ write_psymtabs_to_index (struct objfile *objfile, const char *dir)
do_cleanups (cleanup);
}
-/* The mapped index file format is designed to be directly mmap()able
- on any architecture. In most cases, a datum is represented using a
- little-endian 32-bit integer value, called an offset_type. Big
- endian machines must byte-swap the values before using them.
- Exceptions to this rule are noted. The data is laid out such that
- alignment is always respected.
-
- A mapped index consists of several sections.
-
- 1. The file header. This is a sequence of values, of offset_type
- unless otherwise noted:
-
- [0] The version number, currently 4. Versions 1, 2 and 3 are
- obsolete.
- [1] The offset, from the start of the file, of the CU list.
- [2] The offset, from the start of the file, of the types CU list.
- Note that this section can be empty, in which case this offset will
- be equal to the next offset.
- [3] The offset, from the start of the file, of the address section.
- [4] The offset, from the start of the file, of the symbol table.
- [5] The offset, from the start of the file, of the constant pool.
-
- 2. The CU list. This is a sequence of pairs of 64-bit
- little-endian values, sorted by the CU offset. The first element
- in each pair is the offset of a CU in the .debug_info section. The
- second element in each pair is the length of that CU. References
- to a CU elsewhere in the map are done using a CU index, which is
- just the 0-based index into this table. Note that if there are
- type CUs, then conceptually CUs and type CUs form a single list for
- the purposes of CU indices.
-
- 3. The types CU list. This is a sequence of triplets of 64-bit
- little-endian values. In a triplet, the first value is the CU
- offset, the second value is the type offset in the CU, and the
- third value is the type signature. The types CU list is not
- sorted.
-
- 4. The address section. The address section consists of a sequence
- of address entries. Each address entry has three elements.
- [0] The low address. This is a 64-bit little-endian value.
- [1] The high address. This is a 64-bit little-endian value.
- Like DW_AT_high_pc, the value is one byte beyond the end.
- [2] The CU index. This is an offset_type value.
-
- 5. The symbol table. This is a hash table. The size of the hash
- table is always a power of 2. The initial hash and the step are
- currently defined by the `find_slot' function.
-
- Each slot in the hash table consists of a pair of offset_type
- values. The first value is the offset of the symbol's name in the
- constant pool. The second value is the offset of the CU vector in
- the constant pool.
-
- If both values are 0, then this slot in the hash table is empty.
- This is ok because while 0 is a valid constant pool index, it
- cannot be a valid index for both a string and a CU vector.
-
- A string in the constant pool is stored as a \0-terminated string,
- as you'd expect.
-
- A CU vector in the constant pool is a sequence of offset_type
- values. The first value is the number of CU indices in the vector.
- Each subsequent value is the index of a CU in the CU list. This
- element in the hash table is used to indicate which CUs define the
- symbol.
-
- 6. The constant pool. This is simply a bunch of bytes. It is
- organized so that alignment is correct: CU vectors are stored
- first, followed by strings. */
+/* 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. */
static void
save_gdb_index_command (char *arg, int from_tty)