5acc29041e
The cost of the file layer is large and makes benchmarks too coarse,
as seen for in following example, first with a file, then with a
literal string:
0. %skeleton "yacc.c" %define parse.lac full
1. %skeleton "yacc-v1.c" %define nofinal %define parse.lac full
2. %skeleton "yacc-v2.c" %define nofinal %define parse.lac full
3. %skeleton "yacc-v3.c" %define nofinal %define parse.lac full
4. %skeleton "yacc.c"
5. %skeleton "yacc-v1.c" %define nofinal
6. %skeleton "yacc-v2.c" %define nofinal
7. %skeleton "yacc-v3.c" %define nofinal
--------------------------------------------------
Benchmark Time CPU Iterations
--------------------------------------------------
BM_y0 32558 ns 32537 ns 21228
BM_y1 32400 ns 32369 ns 21233
BM_y2 33485 ns 33464 ns 20625
BM_y3 32139 ns 32125 ns 21446
BM_y4 31343 ns 31329 ns 21747
BM_y5 31344 ns 31317 ns 22035
BM_y6 31287 ns 31255 ns 22039
BM_y7 31387 ns 31373 ns 22178
--------------------------------------------------
Benchmark Time CPU Iterations
--------------------------------------------------
BM_y0 10642 ns 10634 ns 63601
BM_y1 10657 ns 10654 ns 63625
BM_y2 10441 ns 10432 ns 65957
BM_y3 10558 ns 10554 ns 64546
BM_y4 9521 ns 9516 ns 72011
BM_y5 9179 ns 9157 ns 75028
BM_y6 9360 ns 9356 ns 73770
BM_y7 9365 ns 9359 ns 72609
Of course, at the same time it is less realistic: most users read
files rather that strings, so it might lead to us to pay attention to
costs most people don't see.
* etc/bench.pl.in (&calc_input): Output into a file given as argument.
Output in C syntax.
(&generate_grammar_calc): Use it.
Simplify the grammar: remove operators we don't care about.
Rewrite the scanner to work on a char* instead of a FILE*.
This package contains the GNU Bison parser generator.
Installation
Build from git
Here are basic installation instructions for a repository checkout:
$ git submodule update --init
$ ./bootstrap
then proceed with the usual configure && make steps.
The file README-hacking.md is about building, modifying and checking Bison.
Build from tarball
See the file INSTALL for generic compilation and installation instructions.
Bison requires GNU m4 1.4.6 or later. See https://ftp.gnu.org/gnu/m4/m4-1.4.6.tar.gz.
Running a non installed bison
Once you ran make, you might want to toy with this fresh bison before
installing it. In that case, do not use src/bison: it would use the
installed files (skeletons, etc.), not the local ones. Use tests/bison.
Colored diagnostics
As an experimental feature, diagnostics are now colored, controlled by the
--color and --style options.
To use them, install the libtextstyle library before configuring Bison. It is available from https://alpha.gnu.org/gnu/gettext/, for instance https://alpha.gnu.org/pub/gnu/gettext/libtextstyle-0.20.5.tar.gz.
The option --color supports the following arguments:
- always, yes: Enable colors.
- never, no: Disable colors.
- auto, tty (default): Enable colors if the output device is a tty.
To customize the styles, create a CSS file, say bison-bw.css, similar to
/* bison-bw.css */
.warning { }
.error { font-weight: 800; text-decoration: underline; }
.note { }
then invoke bison with --style=bison-bw.css, or set the BISON_STYLE
environment variable to bison-bw.css.
Relocatability
If you pass --enable-relocatable to configure, Bison is relocatable.
A relocatable program can be moved or copied to a different location on the file system. It can also be used through mount points for network sharing. It is possible to make symlinks to the installed and moved programs, and invoke them through the symlink.
See "Enabling Relocatability" in the documentation.
Internationalization
Bison supports two catalogs: one for Bison itself (i.e., for the maintainer-side parser generation), and one for the generated parsers (i.e., for the user-side parser execution). The requirements between both differ: bison needs ngettext, the generated parsers do not. To simplify the build system, neither are installed if ngettext is not supported, even if generated parsers could have been localized. See http://lists.gnu.org/archive/html/bug-bison/2009-08/msg00006.html for more details.
Questions
See the section FAQ in the documentation (doc/bison.info) for frequently
asked questions. The documentation is also available in PDF and HTML,
provided you have a recent version of Texinfo installed: run make pdf or
make html.
If you have questions about using Bison and the documentation does not answer them, please send mail to help-bison@gnu.org.
Bug reports
Please send bug reports to bug-bison@gnu.org. Be sure to include the
version number from bison --version, and a complete, self-contained test
case in each bug report.
Copyright statements
For any copyright year range specified as YYYY-ZZZZ in this package, note that the range specifies every single year in that closed interval.