We have added a facility for determining the proportional amount of
time spent executing compiled lisp defined functions, as well as
internal c defined functions.

This system works under Unix BSD or System V.

To use this code load the file lsp/profile.o.

SET-UP-PROFILE &optional (array-size 100000)(max-funs 6000)


must be called to allocate space for storing the profile information
as it is collected, and also to build a list of the functions from
the symbol table of the executable (defaults to "saved_kcl").

Once this has been done a call to

PROF (start scale)

START will correspond to the beginning of the profile array, and
the SCALE will mean that 256 bytes of code correspond to SCALE bytes in the
profile array.

Thus if the profile array is 1,000,000  bytes long and the code segment is 
5 megabytes long you can profile the whole thing using a scale of 50
Note that long runs may result in overflow, and so an understating of the
time in a function.

With a scale of 128 a sample loop overflowed some slots at 6,000,000
times through the loop.

There is very little slowdown in execution during profiling.  No special
compilation is necessary.

To display the result do

(si::display-profile)

To turn off profiling use (si::prof 0 0).

(si::clear-profile)
clears the profile array for a new run.