Add a settings::FlagsOrIsa struct which represents a flags reference and
optionally the ISA it belongs to. Use this for passing flags/isa
information to the verifier.
The verify_function() and verify_context() functions are now generic so
they accept either a &Flags or a &TargetISa argument.
Fix the return_at_end verifier tests which no longer require an ISA
specified. The signle "set return_at_end" flag setting now makes it to
the verifier even when no ISA is present to carry it.
The flag guarantees that the generated function does not have any
internal return instructions. If the function returns at all, the return
must be the last instruction.
For now just implement a verifier check for this property. When we get
CFG simplifiers and block layout optimizations, they will need to heed
the flag.
* Function names should start with %
* Create FunctionName from string
* Implement displaying of FunctionName as %nnnn with fallback to #xxxx
* Run rustfmt and fix FunctionName::with_string in parser
* Implement FunctionName::new as a generic function
* Binary function names should start with #
* Implement NameRepr for function name
* Fix examples in docs to reflect that function names start with %
* Rebase and fix filecheck tests
This test runs the verifier on each function and matches the resulting
verifier error against the "error:" annotation.
Move the existing verifier test into filetests/verifier/ and use the new
syntex.
