Directed edges are used to represent jumps in
the control flow. Another concept closely related to CFG
is call graph. A call graph (CG) is a directed graph that
represents calling relationship among subroutines in a com-
puter program. Each node in CG represents a subroutine
which can be further divided to multiple basic blocks and
use one CFG to depict the relationship of these blocks. This
statement is based on the fact that interprocedual branches
are extremely rare in modern computer programs. In other
words, for most cases, a CFG is fully contained in a node
of CG. CFG and CG describe the control flow of a program
from different hierarchies. The key point of our proposal is
to dynamically display the current position of execution on
both CG and CFG as the program is running. This is a plain
explanation of the title “animation of control flow for low-
level debugging”. The proposal of this technique is by no
means to replace the conventional debugging methodology.
In fact, they are complementary. The animation tools show
us an intuitive and entire view of how a program is running
while the traditional debuggers provide us more details in
each step. The remaining part of this paper is organized as
follows: in the next section we give a brief summary of oth-
ers’ work related to us