Question

I am trying to implement my own memory allocation code which is simple yet efficient. Any idea where I can start from. What algorithm gcc uses?

Answer 1

This is a problem that has been examined and implemented hundreds of times; chances are your implementation is going to work in a very specific situation and nowhere else. Before spending an extraordinary amount of time attempting to solve this problem yourself, consider existing implementations that beat gcc’s generalized allocation mechanism:

http://goog-perftools.sourceforge.net/doc/tcmalloc.html

http://www.canonware.com/jemalloc/

You could also review the implementation of GCC / glibc itself by reviewing the source releases:

http://gcc.gnu.org/releases.html

http://ftp.gnu.org/gnu/glibc/

Malloc is part of the GNU C Library implementation.