Re: [rfa:symtab] SYMBOL_LOCATION_FUNCS -> SYMBOL_OPS

[Elena Zannoni <ezannoni@redhat.com>]

Andrew Cagney writes:
 > > Hello,
 > > 
 > > This patch generalizes the per-symbol location_funcs, replacing them with a symbol_ops vector (the contents are unchanged).  The patch doesn't change the size of the symbol.
 > > 
 > > As the comment hints:
 > > 
 > > +  /* NOTE: cagney/2003-11-02: The fields "aclass" and "ops" contain
 > > +     overlaping information.  Since GDB has only a small finite number
 > > +     of symbol classes it should be possible to merge the two fields
 > > +     into a single ops-table "index".  Each entry providing both the
 > > +     "ops" and the "aclass" values.  Doing that would shave 32 bits
 > > +     off every symbol.  */
 > > 
 > > The patch sets us up for a more significant change - merge "ops" and "aclass" - and hence eliminates 32 bits (or 20%) of each symbol.  I should note that right now the details of the merge are "left as an exercise for the reader".
 > > 
 > > ok?
 > 
 > Ping?  I revised the comment thus:
 > 
 >    /* NOTE: cagney/2003-11-02: The fields "aclass" and "ops" contain
 >       overlapping information.  By creating a per-aclass ops vector, or
 >       using the aclass as an index into an ops table, the aclass and
 >       ops fields can be merged.  The latter, for instance, would shave
 >       32-bits from each symbol (relative to a symbol lookup, any table
 >       index overhead would be in the noise).  */
 > 

Ok.

elena


 > Andrew
 > 
 > 2003-11-08  Andrew Cagney  <cagney@redhat.com>
 > 
 > 	* dwarf2loc.c (dwarf_expr_frame_base): Use SYMBOL_OPS instead of
 > 	SYMBOL_LOCATION_FUNCS
 > 	(dwarf2_loclist_funcs, dwarf2_locexpr_funcs): Change type to
 > 	"struct symbol_ops".
 > 	* dwarf2loc.h (dwarf2_locexpr_funcs, dwarf2_loclist_funcs): Change
 > 	type to "struct symbol_ops".
 > 	* dwarf2read.c (dwarf2_symbol_mark_computed): Set SYMBOL_OPS
 > 	intead of SYMBOL_LOCATION_FUNCS.
 > 	* ax-gdb.c (gen_var_ref): Ditto for "tracepoint_var_ref".
 > 	* printcmd.c (address_info): Ditto for "describe_location".
 > 	* findvar.c (symbol_read_needs_frame): Call "read_needs_frame"
 > 	when available.  Assert requirement when LOC_COMPUTED or
 > 	LOC_COMPUTED_ARG.
 > 	(read_var_value): Ditto for "read_variable".
 > 	* symtab.h (struct symbol_ops): Rename "struct location_funcs".
 > 	(struct symbol): Replace ".aux_value.loc.funcs" and
 > 	".aux_value.loc.baton" with ".ops" and ".aux_value.ptr".
 > 	(SYMBOL_OBJFILE): Delete macro.
 > 	(SYMBOL_LOCATION_FUNCS): Delete macro.
 > 	(SYMBOL_LOCATION_BATON): Update.