GCC's switch table code generation

[Ian Lance Taylor]

Edd Barrett <vext01@gmail.com> writes:

> I would be really interested to know how GCC:
>  * Decides whether or not to embed tables in the data segment of the binary.
>  * Selects the comparisons in the above tree.

The relevant code is expand_case and friends in gcc/stmt.c.  Where a
jump table should go is decided on a target by target basis by the
backend macro JUMP_TABLES_IN_TEXT_SECTION.

> Perhaps someone knows of a good paper/book on this topic which could
> be of use, or a relevant section of code in the GCC sources (at the
> moment I am overwhelmed by the source tree).

You may be interested in reading Roger Sayle's paper in the 2008 gcc
summit, linked from http://ols.fedoraproject.org/GCC/Reprints-2008/ .

Ian