At some point, pass definitions were heavily macro-ized. Pass
descriptive names were added in two places. This is not only redundant
but a source of confusion. You could waste a lot of time grepping for
the wrong string. I removed all the getName() overrides which, at
around 90 passes, was a fairly significant amount of code bloat.
Any pass that we want to be able to invoke by name from a tool
(sil-opt) or pipeline plan *should* have unique type name, enum value,
commend-line string, and name string. I removed a comment about the
various inliner passes that contradicted that.
Side note: We should be consistent with the policy that a pass is
identified by its type. We have a couple passes, LICM and CSE, which
currently violate that convention.
There are now separate functions for function addition and deletion instead of InvalidationKind::Function.
Also, there is a new function for witness/vtable invalidations.
rdar://problem/29311657
Hoist alloc_stack instructions of 'generic' or resilient type to the entry
block. At the same time also perform a very simple stack coloring analysis.
This does not use a true liveness-analysis yet but rather employs some simple
conservative checks to see whether the live ranges of two alloc_stacks might
interfere.
AllocStackHoisting is an IRGen SIL pass. This allows for using IRGen's type
lowering information. Furthermore, hoisting and merging the alloc_stack
instructions this late does not interfere with SIL optimizations because the
resulting SIL never gets serialized.
This pipeline is run as part of IRGen and has access to the IRGenModule.
Passes that run as part of this pipeline can query for the IRGenModule.
We will use it for the AllocStackHoisting pass. It wants to know if a type is of
non-fixed size.
To break the cyclic dependency between IRGen -> SILOptimizer -> IRGen that would
arise from the SILPassManager having to know about the createIRGENPASS()
function IRGen passes instead of exposing this function dynamically have to add
themselves to the pass manager.
This commit adds the functionality, but does not change SILPassManager to use
it. The reason why I am doing this is so I can implement sil-opt pass bisecting
functionality in python using a tool that dumps the current pass pipelines
out. This will ensure that even in the face of changes to the pass pipelines,
everything should just work.
(Headers first)
It has been generally agreed that we need to do this reorg, and now
seems like the perfect time. Some major pass reorganization is in the
works.
This does not have to be the final word on the matter. The consensus
among those working on the code is that it's much better than what we
had and a better starting point for future bike shedding.
Note that the previous organization was designed to allow separate
analysis and optimization libraries. It turns out this is an
artificial distinction and not an important goal.
