struct axs_value;
struct agent_expr;
-/* Don't do this; it means that if some .o's are compiled with GNU C
- and some are not (easy to do accidentally the way we configure
- things; also it is a pain to have to "make clean" every time you
- want to switch compilers), then GDB dies a horrible death. */
-/* GNU C supports enums that are bitfields. Some compilers don't. */
-#if 0 && defined(__GNUC__) && !defined(BYTE_BITFIELD)
-#define BYTE_BITFIELD :8;
-#else
-#define BYTE_BITFIELD /*nothing */
-#endif
+/* Some of the structures in this file are space critical.
+ The space-critical structures are:
+
+ struct general_symbol_info
+ struct symbol
+ struct partial_symbol
+
+ These structures are layed out to encourage good packing.
+ They use ENUM_BITFIELD and short int fields, and they order the
+ structure members so that fields less than a word are next
+ to each other so they can be packed together. */
+
+/* Rearranged: used ENUM_BITFIELD and rearranged field order in
+ all the space critical structures (plus struct minimal_symbol).
+ Memory usage dropped from 99360768 bytes to 90001408 bytes.
+ I measured this with before-and-after tests of
+ "HEAD-old-gdb -readnow HEAD-old-gdb" and
+ "HEAD-new-gdb -readnow HEAD-old-gdb" on native i686-pc-linux-gnu,
+ red hat linux 8, with LD_LIBRARY_PATH=/usr/lib/debug,
+ typing "maint space 1" at the first command prompt.
+
+ Here is another measurement (from andrew c):
+ # no /usr/lib/debug, just plain glibc, like a normal user
+ gdb HEAD-old-gdb
+ (gdb) break internal_error
+ (gdb) run
+ (gdb) maint internal-error
+ (gdb) backtrace
+ (gdb) maint space 1
+
+ gdb gdb_6_0_branch 2003-08-19 space used: 8896512
+ gdb HEAD 2003-08-19 space used: 8904704
+ gdb HEAD 2003-08-21 space used: 8396800 (+symtab.h)
+ gdb HEAD 2003-08-21 space used: 8265728 (+gdbtypes.h)
+
+ The third line shows the savings from the optimizations in symtab.h.
+ The fourth line shows the savings from the optimizations in
+ gdbtypes.h. Both optimizations are in gdb HEAD now.
+
+ --chastain 2003-08-21 */
+
+
/* Define a structure for the information that is common to all symbol types,
including minimal symbols, partial symbols, and full symbols. In a
multilanguage environment, some language specific information may need to
- be recorded along with each symbol.
+ be recorded along with each symbol. */
- These fields are ordered to encourage good packing, since we frequently
- have tens or hundreds of thousands of these. */
+/* This structure is space critical. See space comments at the top. */
struct general_symbol_info
{
This is used to select one of the fields from the language specific
union above. */
- enum language language BYTE_BITFIELD;
+ ENUM_BITFIELD(language) language : 8;
/* Which section is this symbol in? This is an index into
section_offsets for this objfile. Negative means that the symbol
#define SYMBOL_MATCHES_NATURAL_NAME(symbol, name) \
(strcmp_iw (SYMBOL_NATURAL_NAME (symbol), (name)) == 0)
+/* Classification types for a minimal symbol. These should be taken as
+ "advisory only", since if gdb can't easily figure out a
+ classification it simply selects mst_unknown. It may also have to
+ guess when it can't figure out which is a better match between two
+ types (mst_data versus mst_bss) for example. Since the minimal
+ symbol info is sometimes derived from the BFD library's view of a
+ file, we need to live with what information bfd supplies. */
+
+enum minimal_symbol_type
+{
+ mst_unknown = 0, /* Unknown type, the default */
+ mst_text, /* Generally executable instructions */
+ mst_data, /* Generally initialized data */
+ mst_bss, /* Generally uninitialized data */
+ mst_abs, /* Generally absolute (nonrelocatable) */
+ /* GDB uses mst_solib_trampoline for the start address of a shared
+ library trampoline entry. Breakpoints for shared library functions
+ are put there if the shared library is not yet loaded.
+ After the shared library is loaded, lookup_minimal_symbol will
+ prefer the minimal symbol from the shared library (usually
+ a mst_text symbol) over the mst_solib_trampoline symbol, and the
+ breakpoints will be moved to their true address in the shared
+ library via breakpoint_re_set. */
+ mst_solib_trampoline, /* Shared library trampoline code */
+ /* For the mst_file* types, the names are only guaranteed to be unique
+ within a given .o file. */
+ mst_file_text, /* Static version of mst_text */
+ mst_file_data, /* Static version of mst_data */
+ mst_file_bss /* Static version of mst_bss */
+};
+
/* Define a simple structure used to hold some very basic information about
all defined global symbols (text, data, bss, abs, etc). The only required
information is the general_symbol_info.
char *filename;
#endif
- /* Classification types for this symbol. These should be taken as "advisory
- only", since if gdb can't easily figure out a classification it simply
- selects mst_unknown. It may also have to guess when it can't figure out
- which is a better match between two types (mst_data versus mst_bss) for
- example. Since the minimal symbol info is sometimes derived from the
- BFD library's view of a file, we need to live with what information bfd
- supplies. */
+ /* Classification type for this minimal symbol. */
- enum minimal_symbol_type
- {
- mst_unknown = 0, /* Unknown type, the default */
- mst_text, /* Generally executable instructions */
- mst_data, /* Generally initialized data */
- mst_bss, /* Generally uninitialized data */
- mst_abs, /* Generally absolute (nonrelocatable) */
- /* GDB uses mst_solib_trampoline for the start address of a shared
- library trampoline entry. Breakpoints for shared library functions
- are put there if the shared library is not yet loaded.
- After the shared library is loaded, lookup_minimal_symbol will
- prefer the minimal symbol from the shared library (usually
- a mst_text symbol) over the mst_solib_trampoline symbol, and the
- breakpoints will be moved to their true address in the shared
- library via breakpoint_re_set. */
- mst_solib_trampoline, /* Shared library trampoline code */
- /* For the mst_file* types, the names are only guaranteed to be unique
- within a given .o file. */
- mst_file_text, /* Static version of mst_text */
- mst_file_data, /* Static version of mst_data */
- mst_file_bss /* Static version of mst_bss */
- }
- type BYTE_BITFIELD;
+ ENUM_BITFIELD(minimal_symbol_type) type : 8;
/* Minimal symbols with the same hash key are kept on a linked
list. This is the link. */
/* Different name domains for symbols. Looking up a symbol specifies a
domain and ignores symbol definitions in other name domains. */
-typedef enum
+typedef enum domain_enum_tag
{
/* UNDEF_DOMAIN is used when a domain has not been discovered or
none of the following apply. This usually indicates an error either
struct alias_list *next;
};
+/* This structure is space critical. See space comments at the top. */
+
struct symbol
{
/* Domain code. */
- domain_enum domain BYTE_BITFIELD;
+ ENUM_BITFIELD(domain_enum_tag) domain : 6;
/* Address class */
- enum address_class aclass BYTE_BITFIELD;
+ ENUM_BITFIELD(address_class) aclass : 6;
/* Line number of definition. FIXME: Should we really make the assumption
that nobody will try to debug files longer than 64K lines? What about
on a partial symtab list and which points to the corresponding
normal symtab once the partial_symtab has been referenced. */
+/* This structure is space critical. See space comments at the top. */
+
struct partial_symbol
{
/* Name space code. */
- domain_enum domain BYTE_BITFIELD;
+ ENUM_BITFIELD(domain_enum_tag) domain : 6;
/* Address class (for info_symbols) */
- enum address_class aclass BYTE_BITFIELD;
+ ENUM_BITFIELD(address_class) aclass : 6;
};
projects / deliverable / binutils-gdb.git / blobdiff