1. Code Coverage
David Inglis
November 18, 2018

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Code Coverage
gcc produces all coverage data
Type of Code Coverage
Basic block coverage
block of code defined as not having any branch point within.
Branch Coverage (Path)
tracking paths of execution between blocks.
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Code Coverage
Compiler Options
$(CC) –Wc,-fprofile-arcs –Wc,-ftest-coverage
enables compiler instrumentation which counts execution of branches between basic blocks.
$(LD) -p
links in startup and shutdown code
.da file generation
shutdown code to write .da files for each source file.
qconn connection
program information on startup (obtains pointer to global structure).
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Code Coverage
Compilation
gcc produces 2 files when source if compiled
<source_name>.bbg
Used to reconstruct execution paths between basic block
<source_name>.bb
Used to map basic blocks to a line of code and function
Execution
Path execution counts are maintained in memory
Not using IDE data is written to <source_name>.da files upon exit.
Using IDE the data is read by qconn and returned to the IDE as process runs.
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Code Coverage
IDE
Coverage data presented and stored as a session
Sessions can be combined
If source is available can view line coverage with editor.
If source is not available, or source code can’t be found due to path differences between build machine and IDE*, coverage metrics are still available.
Reports can be viewed “online” or saved to a file.
Easily imported into excel.
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