mesa/src/glsl/glcpp
Kenneth Graunke b823b99ec0 glcpp: Don't strlen() the output for every token being printed.
The ralloc string appending functions were originally intended for
simple, non-hot-path uses like printing to an info log.

Cuts Unigine Tropics load time by around 20% (6 seconds).

v2: Avoid strlen() on every newline, too.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com> [v1]
Acked-by: José Fonseca <jfonseca@vmware.com> [v1]
2012-02-28 13:07:12 -08:00
..
tests glsl: Add glcpp tests for a macro used twice 2012-02-02 12:05:21 -08:00
.gitignore Revert "automake: src/glsl and src/glsl/glcpp" 2012-01-31 21:33:59 -05:00
glcpp-lex.l glcpp: Fix so that trailing punctuation does not prevent macro expansion 2012-02-02 12:05:21 -08:00
glcpp-parse.y glcpp: Don't strlen() the output for every token being printed. 2012-02-28 13:07:12 -08:00
glcpp.c glsl: Silence several "warning: unused parameter" 2011-09-09 12:01:50 -07:00
glcpp.h glcpp: Don't strlen() the output for every token being printed. 2012-02-28 13:07:12 -08:00
pp.c Convert everything from the talloc API to the ralloc API. 2011-01-31 10:17:09 -08:00
README Revert "glcpp: Demote "macro redefined" from an error to a warning" 2011-01-29 08:21:05 +10:00

glcpp -- GLSL "C" preprocessor

This is a simple preprocessor designed to provide the preprocessing
needs of the GLSL language. The requirements for this preprocessor are
specified in the GLSL 1.30 specification availble from:

http://www.opengl.org/registry/doc/GLSLangSpec.Full.1.30.10.pdf

This specification is not precise on some semantics, (for example,
#define and #if), defining these merely "as is standard for C++
preprocessors". To fill in these details, I've been using a draft of
the C99 standard as available from:

http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf

Any downstream compiler accepting output from glcpp should be prepared
to encounter and deal with the following preprocessor macros:

	#line
	#pragma
	#extension

All other macros will be handles according to the GLSL specification
and will not appear in the output.

Known limitations
-----------------
The __LINE__ and __FILE__ macros are not yet supported.

A file that ends with a function-like macro name as the last
non-whitespace token will result in a parse error, (where it should be
passed through as is).