The `SmallProjectionPath` represents a path of value or address projections.
It’s used for defining argument effects for functions and for the new escape analysis.
The `run-unit-tests` is a "pseudo" pass which is invoked from sil-opt and runs all the unit tests, implemented in Swift.
This is done from the `swift-unit-tests.sil` lit test.
For inserting new instruction after another instruction. This is especially interesting if the insertion point is a terminator.
In this case, the new instruction(s) are inserted in the successor block(s).
* add `BasicBlockSet`
* add `BasicBlockWorklist`
* add `BasicBlockRange`, which defines a range of blocks from a common dominating “begin” block to a set of “end” blocks.
* add `InstructionRange`, which is similar to `BasicBlockRange`, just on instruction level. It can be used for value lifetime analysis.
* rename `StackList` -> `Stack` and move it to `Optimizer/DataStructures`
* rename `PassContext.passContext` to `PassContext._bridged`
* add notify-functions to PassContext
Improve block/instruction lists and similar collections
* pretty print collections in the form “[a, b, c]”
* also do this for lazy sequences
* define a custom Mirror
* in a collection, only print the name of blocks, functions and globals (instead of the full object)
* replace `BasicBlock.reverseInstructions` with `BasicBlock.instructions.reversed()` - in an efficient way
