GPGPU Programming for Games and Science

Practical Matters 253

or which lines of code are executed. Function coverage is useful mainly for

high-level measurements of what parts of your code base are actually being

used. Line coverage is, perhaps, too fine a measurement—if you have n lines

without branching, all lines will be executed.

In my experience at Microsoft, the automated code coverage tools used

block counting where the blocks are determined from the generated assembly

code. One block is a sequence of assembly instructions without branching. Al-

though this makes sense at a high level, there are some low-level consequences

that you must keep in mind. Firstly, the assembly code generated ...