Replace Ops.<...> with a custom @op macro

[avik-pal]

Currently we get location info in the Ops file. This will let us populate the location info from where the corresponding Ops.<...> is being made.

Essentially

res = @op convert(....)

gets converted into

res = Ops.convert(....; ...., location = ....)

with the location info of the current line automatically populated.

[mofeing]

That would be very nice and quite easy. The solution I thought for this (which is still interesting for profiling) is to create a custom mlir::Location that takes a Julia callstack snapshot without actually solving the caller symbols (until requested).

Also, with this the Ops.with_debug would be become useless and can be removed. It just calls stacktrace and converts each StackFrame into a MLIR.IR.Location which is extremely slow.

[wsmoses]

with_debug still has use, since that gets the full stacktrace and not just the line which called it (e.g. we would now see +(TracedRArray, TracedRArray) but not who calls +)

[mofeing]

true, but current implementation has a high overhead