CptnHook

A profiler to investigate the usage patterns of mathematical functions capturing the input values and the stacktraces which lead to it. No code instrumentation nor recompilation is needed: the principle behind CtpnHook is library preload. The principle is to save in a profile for every mathematical function (both for single and double precision) a two column n-tuple containing the input value and a stacktrace ID. The map between the IDs and the stacktraces themselves is saved as well. This version of cptnHook is inspired by https://github.com/emyrto/cptnHook but is standalone: it does not depend on any external library such as cctlib or PIN.

How to build

Clone the repository and then:

mkdir build
cd build
cmake ../cptnHookLite
make
export PATH=`pwd`:$PATH

Obtaining a profile

cptnhook -o myFirstProfile -- myprogram --arg1 --arg2 arg3

This will generate a directory called myFirstProfile containing the raw profile. The information

List of intercepted functions

The list of intercepted functions is the following (both single and double precision):

• sin, cos, exp, tan, sinh, cosh, tanh
• The inverse of the above ones
• cbrt

How to produce a report

cptnhook-analyze myFirstProfile

Converting to ROOT format

Make sure to have ROOT installed. Then there are two ways of converting to ROOT format the raw profile. Either manually with a script

cptnhook-analyze --root myFirstProfile

or directly specifying this in the invocation of cptnhook

cptnhook -o myFirstProfile --root -- myprogram --arg1 --arg2 arg3

MetaLibm

CptnHook has been developed in the context of the MetaLibm project, financed by French National Research Agency (ANR).