X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/c9ba9e5978cfb973f915af1e699c1eebd3d99c0c..7484f1d4f3a173a2d8a5f08b8b561d31118c29e1:/ChangeLog diff --git a/ChangeLog b/ChangeLog index ca2c184f..c15a1541 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,124 @@ +2008-11-03 Akim Demaille + + Improve genericity of bench.pl. + * etc/bench.pl.in (&bench_grammar): Take the set of benches as + argument. + (&bench_push_parser): New. + Call it. + +2008-11-03 Akim Demaille + + Add documentation to bench.pl. + * etc/bench.pl.in: Comment changes. + +2008-11-03 Akim Demaille + + Fuse the three stacks into a single one. + In order to make it easy to perform benchmarks to ensure that there are no + performance loss, lalr1.cc is forked into lalr1-fusion.cc. Eventually, + lalr1-fusion.cc will replace lalr1.cc. + + Meanwhile, to make sure that lalr1-fusion.cc is correctly exercized by the + test suite, the user must install a symbolic link from lalr1.cc to it. + + Instead of having three stacks (state, value, location), use a stack + of triples. This considerably simplifies the code (and it will be + easier not to require locations as currently does the C++ parser), + and also gives a 10% speedup according to etc/bench (probably mainly since + memory allocation is done once instead of three times). + + Another motivation is to make it easier to destruct properly + semantic values: now that they are bound to their state (hence + symbol type) it will be easier to call the appropriate destructor. + + These changes should probably benefit the C parser too. + + * data/lalr1.cc: Copy as... * data/lalr1-fusion.cc: this new + file. + (b4_rhs_value, b4_rhs_location): New definitions overriding those + from c++.m4. + (state_stack_type, semantic_stack_type, location_stack_type) + (yystate_stack_, yysemantic_stack_, yylocation_stack_): Remove. + (data_type, stack_type, yystack_): New. + (YYLLOC_DEFAULT, yypush_): Adjust. + (yyerror_range): Now based on data_type, not location_type. + +2008-11-03 Akim Demaille + + Push the state, value, and location at the same time. + This is needed to prepare a forthcoming patch that fuses the three + stacks into one. + + * data/lalr1.cc (parser::yypush_): New. + (parser::yynewstate): Change the semantics: instead of arriving to + this label when value and location have been pushed, but yystate + is to be pushed on the state stack, now the three of them must + have been pushed before. yystate still must be the new state. + This allows to use yypush_ everywhere instead of individual + handling of the stacks. + +2008-11-03 Akim Demaille + + Prefer references to pointers. + * data/lalr1.cc (b4_symbol_actions): New, overrides the default C + definition to use references instead of pointers. + (yy_symbol_value_print_, yy_symbol_print_, yydestruct_): + Take the value and location as references. + Adjust callers. + +2008-11-03 Akim Demaille + + stack::size instead of stack::height. + * data/lalr1.cc (stack::height): Rename as... + (stack::size): this. + Fix the output type. + Comment changes. + +2008-11-03 Akim Demaille + + Use variants to support objects as semantic values. + This patch was inspired by work by Michiel De Wilde. But he used Boost + variants which (i) requires Boost on the user side, (ii) is slow, and + (iii) has useless overhead (the parser knows the type of the semantic value + there is no reason to duplicate this information as Boost.Variants do). + + This implementation reserves a buffer large enough to store the largest + objects. yy::variant implements this buffer. It was implemented with + Quentin Hocquet. + + * src/output.c (type_names_output): New. + (output_skeleton): Invoke it. + * data/c++.m4 (b4_variant_if): New. + (b4_symbol_value): If needed, provide a definition for variants. + * data/lalr1.cc (b4_symbol_value, b4_symbol_action_) + (b4_symbol_variant, _b4_char_sizeof_counter, _b4_char_sizeof_dummy) + (b4_char_sizeof, yy::variant): New. + (parser::parse): If variants are requested, define + parser::union_type, parser::variant, change the definition of + semantic_type, construct $$ before running the user action instead + of performing a default $$ = $1. + * examples/variant.yy: New. + Based on an example by Michiel De Wilde. + +2008-11-03 Akim Demaille + + Parameterize the extraction of semantic values. + To make future changes easier, no longer rely on ".TYPE" being the + way to get a semantic value. + + * data/c.m4 (b4_symbol_value): New. + Use it. + * data/c++.m4, data/yacc.c: Use it. + * data/glr.c: Use b4_symbol_value. + (b4_rhs_data): New. + Use it. + +2008-11-03 Akim Demaille + + Prepare easier M4 changes. + * data/lalr1.cc: Use escaped [] instead of literals to prepare + future changes. + 2008-11-02 Joel E. Denny Initiate further development.