In the graphical version, there is a small window with arrows on the left of the disassembly. These arrows represent the execution flow, namely the branch and jump instructions. The arrow color can be:
- red: means that the arrow source and destination do not
belong to the same function. Usually, the branches are
within functions and the red color will conspicuously
represent branches from or to different functions.
- black: the currently selected arrow. The selection
is made by moving to the beginning or the end of the
arrow using the Up or Down keys or left-clicking on the arrow
start or the arrow end. The selection is
not changed by pressing the PageUp, PageDown, Home, End keys or using
the scrollbar. This allows to trace the selected arrow far away.
- grey: all other arrows
The arrow thickness can be:
- thick: a backward arrow. Backward arrows usually represent
loops. Thick arrows represent the loops in a clear and
notable manner.
- thin: forward arrows.
Finally, the arrows can be solid or dotted. The dotted arrows represent conditional branches when the solid arrows represent unconditional branches.
You can resize the arrows window using a vertical splitter or even fully hide it. If it is hidden, the arrows window will not be visible on the screen but you can reveal it by dragging the splitter to the right. IDA remembers the current arrow window size in the registry when you close the disassembly window.