add code coverage host functions

[praphael]

Change Description

Adds new host functions to support contract code coverage.

Change Type

Select ONE:

• Documentation

• Stability bug fix

• Other

• Other - special case

Testing Changes

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• New Tests

• Existing Tests

• Test Framework

• CI System

• Other

Consensus Changes

• Consensus Changes

API Changes

• API Changes

Documentation Additions

• Documentation Additions

[heifner]

These new host functions should only be added to eosio-tester and rodeos not nodeos.

[praphael]

These new host functions should only be added to eosio-tester and rodeos not nodeos.

I'm not sure its possible with only an eosio-tester modification. Tester intrinsics only appear to work with test contracts. The test contract uses a special framework which in turn calls the normal contracts. It also has to define main(), which normal contracts don't. So I don't believe our normal contracts can be compiled as test contracts so they can use pure tester intrisics.

I have verified that the recent commit 7e6b809 works through the whole cycle,. and generates a reasonable code coverage report. We don't actually have to merge this in, we could keep it as a separate branch just for the purpose of using code coverage.

[heifner]

Is this used?