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Re: Re[2]: object code execution statistics


On Tue, 2005-04-26 at 01:57, Sergei Tovpeko wrote:
> Does it mean that GCOV have much more data (in its binary format)
> but don't treat them and out to user in human format?

We have branch taken/not-taken counts, and from that, we can compute
basic block execution counts and branch probabilities.  gcov then uses a
basic block to line number map to convert this into line number
execution counts for the pretty printed source output.

There are certainly other things that could be done with the info.

Applying execution counts to assembly instructions is probably not very
useful to the end user.  It is too hard to map source code to assembly
code after optimization.  It might be interesting to generate statistics
though, e.g. computing the percentage of executed instructions that were
nops, the percent that were moves, etc.
-- 
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com



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