This runs the data layout analysis pass added in the previous change twice:
Once for the host architecture and once for the guest architecture. This
allows the new DataLayoutCompareAction to query architecture differences for
each type, which can then be used to instruct code generation accordingly.
Currently, type compatibility is classified into 3 categories:
* Fully compatible (same size/alignment for the type itself and any members)
* Repackable (incompatibility can be resolved with emission of automatable
repacking code, e.g. when struct members are located at differing offsets
due to padding bytes)
* Incompatible
The run_thunkgen* helpers now parse generated source code and return its AST
representation, so HasASTMatching helper calls don't each need to redundantly
compile it themselves. This also ensures the generator output actually compiles
in tests where we didn't explicitly check that before.
This also allows printing the full AST of the generator output on test
failures. This must be enabled manually by changing a variable in the ostream
output operator for SourceWithAST.
Paulo Matos