This change makes the IR builder use the type manager to generate
OpTypeInts when creating OpConstants. This avoids dangling references
being stored by the created OpConstants.
* Had to remove templating from InstructionBuilder as a result
* now preserved analyses are specified as a constructor argument
* updated tests and uses
* changed static_assert to a runtime assert
* this should probably get further changes in the future
* Handles simple cases only
* Identifies phis in blocks with two predecessors and attempts to
convert the phi to an select
* does not perform code motion currently so the converted values must
dominate the join point (e.g. can't be defined in the branches)
* limited for now to two predecessors, but can be extended to handle
more cases
* Adding if conversion to -O and -Os
The class factorize the instruction building process.
Def-use manager analysis can be updated on the fly to maintain coherency.
To be updated to take into account more analysis.
