Add two new arguments:
- table_index is the WebAssembly table referenced in the indirect call.
- sig_index is the WebAssembly signature index. We still have the SigRef
that was created by make_indirect_sig(), but the WebAssembly signature
index may be needed for detecting type mismatches at runtime.
Change the insertion location to a plain FuncCursor rather than a
FunctionBuilder<Local>. The fact that cretonne-wasm uses FunctionBuilder
should be an implementation detail, and the callbacks don't need to
access WebAssembly locals, so they don't need the extended interface.
Add a FunctionBuilder::cursor() method which creates a FuncCursor for
inserting instructions in the current EBB.
Also add a FuncEnvironment::translate_call() method which allows the
environment to override direct calls the same way as indirect calls.
26048c2ecc