As the _MatchingEngine module no longer contains the matching engine, this patch renames this module to describe its role more accurately. Because this module primarily contains the AST and the regex parsing logic, I propose we rename it to "_RegexParser".
Also renames the ExperimentalRegex module in SwiftCompilerSources to _RegexParser for consistency. This would prevent errors if sources in _RegexParser used qualified lookup with the module name.
The release-devirtualizer must not run on the same alloc_ref twice.
This is a very rare case, but if it happens it's a very bad thing, because it results in a double-free crash.
The fix is to detect that a dealloc_ref instruction (although it isn't "releasing"), does a memory deallocation.
Found by doing some unrelated experiments.
Store a list of argument effects in a function, which specify if and how arguments escape.
Such effects can be specified in the Swift source code (for details see docs/ReferenceGuides/UnderscoredAttributes.md) or derived in an optimization pass.
For details see the documentation in SwiftCompilerSources/Sources/SIL/Effects.swift.
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
