Selecting

Selecting is the process of highlighting all or portions of a program in order to perform a task (for example, modular analysis) on the selection. Selecting can be done manually in providers that support selection, like the Code Browser. Selecting can be done based on subroutines, functions, or by following certain types of control flows in the program.

Selections can be created manually within the Code Browser. There are also some predefined types of selections that are available from the tool Select menu. Each predefined type of selection exposes different characteristics of the program.

To create a selection using one of the predefined methods via the menu item SelectSelectionType.

The SelectionTypes and their descriptions are as follows:

Predefined Selection Methods

Selection Type

Description
Program Changes Select all program changes.

All Flows From

This follows all program flows from the cursor location if no selection or from the selected code units if there is a selection. Select All Flows will traverse all branches conditional and unconditional. All the code units that are traversed are selected.

All Flows To

This selects all program flows to the cursor location if no selection or to the selected code units if there is a selection. Select All Flows To will traverse all branches conditional and unconditional. All the code units that are traversed are selected.

In other words, this follows all program flows backwards from the location or selection.

Limited Flows From

The types of program flows to be followed in this case are based on options configured on the Selection by Flow Options tab. Limited Flows only follows the indicated types of program flows from the cursor location if no selection or from the selected code units if there is a selection. All the code units that are traversed are selected.

Limited Flows To

The types of program flows to be followed in this case are based on options configured on the Selection by Flow Options tab. Limited Flows To only follows the indicated types of program flows to the cursor location if no selection or to the selected code units if there is a selection. All the code units that are traversed are selected.

In other words, this follows the types of program flows, as indicated by the options, backwards from the location or selection.

Subroutine

If there is no selection, this selects the code units of the subroutine that contains the current cursor location. If there is a selection, this selects all the subroutines that contain the selected code units.
Dead Subroutines Selects the code units of all subroutines that not directly referenced, also known as "dead" code.

Function

If there is no selection, this selects the code units of the function that contains the current cursor location. If there is a selection, this selects all the functions that contain the selected code units.

All in View

Selects all code units being displayed in the browser view.

Clear Selection

Clears the current selection in the browser view.
Complement Changes the selection to everything in the current view that is not in the current selection.
Mark and Select Creates a selection in a two step process. The first time the action is invoked, the current location is marked. The second time the action is invoked, a selection is created from the marked location to the current location.
Data Selects all the defined data in the current program if there isn't a selection. Otherwise, it selects the defined data within the current selection.
Instructions Selects all the instructions in the current program if there isn't a selection. Otherwise, it selects the instructions within the current selection.
Undefined Data Selects all the undefined data in the current program if there isn't a selection. Otherwise, it selects the undefined data within the current selection.
Forward Refs Selects all addresses that the current address is referring to.
Back Refs Selects all addresses that refer to the current address.

Selections are meant to be temporary. For example, a left mouse click outside a selection in the Code Browser will make the selection go away. Also, creating a new selection replaces any previous selection rather than adding to it. To retain a selection in a manner that isn't so transient, change it to a highlight.

At any time you can restore the previous selection for the current program by pressing the SelectRestore Selection.

Selection by Flow Tool Options

The Select By Flow plugin adds options to the tool. To view or edit the option settings:

The Selection by Flow tab contains options for indicating the types of flows that will be followed when selecting Limited Flows. The table below lists the Selection by Flow options and their default settings. To follow a particular flow type simply click on the box to check it.

Flow Type to Follow Default
Follow computed call false
Follow computed jump false
Follow conditional call false
Follow conditional jump true
Follow pointers false
Follow unconditional call false
Follow unconditional jump true

Example: Given Follow conditional jump and Follow unconditional jump are the only types checked. As the program flow is followed the instructions that are encountered are added to the selection, wherever the program jumps will also get added to the selection and the program flow is also followed from there. If a conditional call is encountered, then this instruction gets added to the selection. But the conditional call is not followed and the code at the call's destination is not added since this type isn't being followed. The code for the subroutine at the call's destination could still end up in the selection, if it is flowed to by a different flow path using the flow types being followed.

Provided by: Select By Flow Plugin



Navigating Over a Selection

A selection will often consist of one or more address ranges. The address ranges do not have to be contiguous. The navigation margin can be used to directly move the location to a particular selected range. To move to the next or previous selection range relative to the current cursor location use the Next Selected Range and Previous Selected Range buttons.

Using the Navigation Margin

One or more green markers will appear in the Navigation Margin, where each green marker corresponds to an address range included in the selection. Clicking on a green marker will cause the Code Browser to navigate to the beginning of the corresponding address range.

Next Selected Range

To move the program's cursor location to the beginning of the next selected range of addresses:

From the menu-bar of the Code Browser, select Navigation Next Selected Range

OR

From the tool-bar of the Code Browser, click the Go to next selected range () button

When the Code Browser is on or after the last address range in the selection, the "Next Selected Range" menu-bar and tool-bar options will be disabled.

Previous Selected Range

To move the program's cursor location to the beginning of the next selected range of addresses:

From the menu-bar of the Code Browser, select NavigationPrevious Selected Range

OR

From the tool-bar of the Code Browser, click the Go to previous selected range () button

When the Code Browser is on or before the first address range in the selection, the "Previous Selected Range" menu-bar and tool-bar options will be disabled.

Provided by: Go To Next-Previous Selected Range Plugin

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