Object Code coverage is a metric used in software testing to measure the extent to which the compiled or object code, which is the machine-readable code generated by a compiler from the original source code, has been executed during testing.
Object Code Coverage
Object code coverage measure reports whether each machine language conditional branch instruction both took the branch and fell through. This measure gives results that depend on the compiler rather than the program structure since compiler code generation and optimization techniques can create object code that bears little similarity to the original source code structure.
Since branches disrupt the instruction pipeline, compilers sometimes avoid generating a branch and instead generate an equivalent sequence of non-branching instructions. Compilers often expand the body of a function inline to save the cost of a function call. If such functions contain branches, the number of machine language branches increases dramatically relative to the original source code.
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