Software Quality Objectives

The Software Quality Objectives or SQOs are a set of thresholds against which you can compare your verification results. You can develop a review process based on the Software Quality Objectives. In your review process, you consider only those results that cause your project to fail a certain SQO level.

You can use a predefined SQO level or define your own SQOs. Following are the quality thresholds specified by each predefined SQO.

 SQO Level 1

Code that satisfies SQO Level 1 requirements must have code complexity metrics below specified thresholds and zero unjustified violations of certain external coding standard rules (for instance, MISRA C^®: 2012 or MISRA^® C++ rules).

Metric	Threshold Value
Comment density of a file	20 (lower limit)
Number of paths through a function	80
Number of goto statements	0
Cyclomatic complexity	10
Number of calling functions	5
Number of calls	7
Number of parameters per function	5
Number of instructions per function	50
Number of call levels in a function	4
Number of return statements in a function	1
Language scope, an indicator of the cost of maintaining or changing functions. Calculated as follows: (N1+N2) / (n1+n2) n1 — Number of different operators N1 — Total number of operators n2 — Number of different operands N2 — Total number of operands	4
Number of recursions	0
Number of direct recursions	0
Number of unjustified violations of the following MISRA C:2004 rules: 5.2 8.11, 8.12 11.2, 11.3 12.12 13.3, 13.4, 13.5 14.4, 14.7 16.1, 16.2, 16.7 17.3, 17.4, 17.5, 17.6 18.4 20.4	0
Number of unjustified violations of the following MISRA C:2012 rules: 8.8, 8.11, and 8.13 11.1, 11.2, 11.4, 11.5, 11.6, and 11.7 14.1 and 14.2 15.1, 15.2, 15.3, and 15.5 17.1 and 17.2 18.3, 18.4, 18.5, and 18.6 19.2 21.3	0
Number of unjustified violations of the following MISRA C++ rules: 2-10-2 3-1-3, 3-3-2, 3-9-3 5-0-15, 5-0-18, 5-0-19, 5-2-8, 5-2-9 6-2-2, 6-5-1, 6-5-2, 6-5-3, 6-5-4, 6-6-1, 6-6-2, 6-6-4, 6-6-5 7-5-1, 7-5-2, 7-5-4 8-4-1 9-5-1 10-1-2, 10-1-3, 10-3-1, 10-3-2, 10-3-3 15-0-3, 15-1-3, 15-3-3, 15-3-5, 15-3-6, 15-3-7, 15-4-1, 15-5-1, 15-5-2 18-4-1	0

 SQO Level 2

In addition to all the requirements of SQO Level 1, code that satisfies SQO Level 2 requirements must also have zero unjustified red checks (including non-terminating calls and loops, which are second order red checks from orange checks in function calls and loop bodies).

Metric	Threshold Value
Number of unjustified red checks	0
Number of unjustified Non-terminating call and Non-terminating loop checks	0

 SQO Level 3

In addition to all the requirements of SQO Level 2, code that satisfies SQO Level 3 requirements must also have zero unjustified gray checks.

Metric	Threshold Value
Number of unjustified gray Unreachable code checks	0

 SQO Level 4

In addition to all the requirements of SQO Level 3, code that satisfies SQO Level 4 requirements must also have at least a certain percentage of orange checks justified. The percentage depends on the type of checks.

Metric	Threshold Value
Percentage of justified orange checks, calculated as the number of green and justified orange checks divided by the total number of green and orange checks.	Invalid C++ specific operations: 50
	Correctness condition: 60
	Division by zero: 80
	Uncaught exception: 50
	Function not returning value: 80
	Illegally dereferenced pointer: 60
	Return value not initialized: 80
	Non-initialized local variable: 80
	Non-initialized pointer: 60
	Non-initialized variable: 60
	Null this-pointer calling method: 50
	Incorrect object oriented programming: 50
	Out of bounds array index: 80
	Overflow: 60
	Invalid shift operations: 80
	User assertion: 60

 SQO Level 5

In addition to all the requirements of SQO Level 4, code that satisfies SQO Level 5 requirements must also have zero unjustified violations of additional rules from external coding standards and higher percentage of orange checks justified.

Metric	Threshold Value
Number of unjustified violations of the following MISRA C:2004 rules: 6.3 8.7 9.2, 9.3 10.3, 10.5 11.1, 11.5 12.1, 12.2, 12.5, 12.6, 12.9, 12.10 13.1, 13.2, 13.6 14.8, 14.10 15.3 16.3, 16.8, 16.9 19.4, 19.9, 19.10, 19.11, 19.12 20.3	0
Number of unjustified violations of the following MISRA C:2012 rules: 11.8 12.1 and 12.3 13.2 and 13.4 14.4 15.6 and 15.7 16.4 and 16.5 17.4 20.4, 20.6, 20.7, 20.9, and 20.11	0
Number of unjustified violations of the following MISRA C++ rules: 3-4-1, 3-9-2 4-5-1 5-0-1, 5-0-2, 5-0-7, 5-0-8, 5-0-9, 5-0-10, 5-0-13, 5-2-1, 5-2-2, 5-2-7, 5-2-11, 5-3-3, 5-2-5, 5-2-6, 5-3-2, 5-18-1 6-2-1, 6-3-1, 6-4-2, 6-4-6, 6-5-3 8-4-3, 8-4-4, 8-5-2, 8-5-3 11-0-1 12-1-1, 12-8-2 16-0-5, 16-0-6, 16-0-7, 16-2-2, 16-3-1	0
Percentage of justified orange checks, calculated as the number of green and justified orange checks divided by the total number of green and orange checks.	Invalid C++ specific operations: 70
	Correctness condition: 80
	Division by zero: 90
	Uncaught exception: 70
	Function not returning value: 90
	Illegally dereferenced pointer: 70
	Return value not initialized: 90
	Non-initialized local variable: 90
	Non-initialized pointer: 70
	Non-initialized variable: 70
	Null this-pointer calling method: 70
	Incorrect object oriented programming: 70
	Out of bounds array index: 90
	Overflow: 80
	Invalid shift operations: 90
	User assertion: 80

 SQO Level 6

In addition to all the requirements of SQO Level 5, code that satisfies SQO Level 6 requirements must have a significantly higher percentage of orange checks justified.

Metric	Threshold Value
Percentage of justified orange checks, calculated as the number of green and justified orange checks divided by the total number of green and orange checks.	Invalid C++ specific operations: 90
	Correctness condition: 100
	Division by zero: 100
	Uncaught exception: 90
	Function not returning value: 100
	Illegally dereferenced pointer: 80
	Return value not initialized: 100
	Non-initialized local variable: 100
	Non-initialized pointer: 80
	Non-initialized variable: 80
	Null this-pointer calling method: 90
	Incorrect object oriented programming: 90
	Out of bounds array index: 100
	Overflow: 100
	Invalid shift operations: 100
	User assertion: 100

 SQO Exhaustive

In addition to all the requirements of SQO Level 1, code that satisfies SQO Exhaustive requirements must have zero violations of rules from external coding standards and zero unjustified red, gray and orange checks.

The thresholds for coding rule violations apply only if you check for coding rule violations.

Metric	Threshold Value
Number of unjustified MISRA C and MISRA C++ coding rule violations	0
Number of unjustified red checks	0
Number of unjustified Non-terminating call and Non-terminating loop checks	0
Number of unjustified gray Unreachable code checks	0
Percentage of justified orange checks, calculated as the number of green and justified orange checks divided by the total number of green and orange checks.	100

For information on the rationales behind these levels, see Software Quality Objectives for Source Code.

Comparing Verification Results Against Software Quality Objectives

You can compare your verification results against SQOs either in the Polyspace^® user interface or the Polyspace Metrics web interface.

• In the Polyspace user interface, you can use the menu in the Results List toolbar to display only those results that you must fix or justify to attain a certain Software Quality Objective.

  

  To activate the SQO options in this menu, select Tools > Preferences. On the Review Scope tab, select Include Quality Objectives Scope.

• In the Polyspace Metrics web interface, you can first determine whether your project fails to attain a certain Software Quality Objective. The web interface generates a Quality Status of PASS or FAIL for your project. If your project has a Quality Status of FAIL, the web interface highlights in red those results that you must fix or justify to attain the Software Quality Objective. You can choose to only download those results to the Polyspace user interface and review them. For more information, see Compare Metrics Against Software Quality Objectives.

  You can also generated reports that show the PASS or FAIL status using the templates SoftwareQualityObjectives_Summary and SoftwareQualityObjectives. See Bug Finder and Code Prover report (-report-template).

Note

You cannot use the menu in the user interface to suppress red or gray checks. Therefore, you cannot directly compare your project against predefined SQO levels 1, 2 and 3 in the Polyspace user interface. However, in the Polyspace Metrics web interface, you can compare your project against all predefined SQO levels.