I am doing this so I can start writing DI tests without this lowering occuring.
There never was a real reason for this code to be in DI beyond convenience. Now
it just makes writing tests more difficult. To prevent any test delta, I changed
all current DI tests to run this pass after DI.
SubstitutionMaps are now just a trivial pointer-sized value, so
pass them by value instead.
I did have to move a couple of functors from Type.h to SubstitutionMap.h
to resolve some issues with forward declarations.
There are ~100 significant benchmark regressions (of ~350) with -O
-enforce-exclusivity=checked.
This optimization roughly cuts the overhead in half for almost all of those
regressions. These are the top 30 improvements with the optimization enabled.
XorShift....................................................2.83x
ReversedArray...............................................2.76x
RangeIterationSigned........................................2.67x
ExclusivityGlobal...........................................2.57x
Random......................................................2.44x
ReversedDictionary..........................................2.41x
GeekbenchGEMM...............................................2.35x
ArrayInClass................................................2.31x
StringWalk..................................................2.29x
Ary.........................................................2.25x
Ary3........................................................2.25x
Ary2........................................................2.21x
MultiFileTogether...........................................2.17x
MultiFileSeparate...........................................2.17x
RecursiveOwnedParameter.....................................2.14x
LevenshteinDistance.........................................2.04x
HashTest....................................................1.97x
Voronoi.....................................................1.94x
NopDeinit...................................................1.92x
Life........................................................1.89x
Richards....................................................1.84x
Rectangles..................................................1.74x
MatMul......................................................1.71x
LinkedList..................................................1.51x
GeekbenchFFT................................................1.47x
Xcbuild_OutputByteStreamPerfTests...........................1.39x
ObjectAllocation............................................1.33x
MapReduceLazyCollection.....................................1.30x
Prims.......................................................1.28x
CharIndexing_tweet_unicodeScalars_Backwards.................1.28x
Use AccessedStorageAnalysis to find access markers with no nested conflicts.
This optimization analyzes the scope of each access to determine
whether it contains a potentially conflicting access. If not, then it
can be demoted to an instantaneous check, which still catches
conflicts on any enclosing outer scope.
This removes up to half of the runtime calls associated with
exclusivity checking.
The actual algorithm used here has not changed at all so this is basically a NFC
commit. What this PR does is change the underlying algorithm to return the
operands that it computes internally rather than transforming the operand list
into the user list internally. This enables the callers of the optimization to
find the operand number related to the uses. This makes working with
instructions with multiple operands much easier since one does not need to mess
around with rederiving the operand number from the user instruction/SILValue
pair.
getRCUsers() works now by running getRCUses() internally and then maps the
operand list to the user list.
rdar://38196046
There isn't a clean cut point here, so switch
GenericSpecializationInformation from SubstitutionList to
SubstitutionMap and carry along dual SubstitutionMap/SubstitutionList
representations for a small part of ReabstractionInfo.
This functionality is really specific to FunctionSignatureOpts. It really
doesn't make sense to have it as a utils until it becomes more general or we
need it in multiple places.
NFC.
rdar://38196046
An interprocedural analysis pass that summarizes the dynamically
enforced formal accesses within a function. These summaries will be
used by a new AccessEnforcementOpts pass to locally fold access scopes
and remove dynamic checks based on whole module analysis.
I am going to be adding logic here to enable apple/swift#1550 to be completed.
The rename makes sense due to precedent from LLVM's codegen prepare and also
since I am going to be expanding what the pass is doing beyond just "cleaning
up". It is really a grab bag pass for performing simple transformations that we
do not want to pollute IRGen's logic with.
https://github.com/apple/swift/pull/15502
rdar://39335800
Make this a generic analysis so that it can be used to analyze any
kind of function effect.
FunctionSideEffect becomes a trivial specialization of the analysis.
The immediate need for this is to introduce an new
AccessedStorageAnalysis, although I foresee it as a generally very
useful utility. This way, new kinds of function effects can be
computed without adding any complexity or compile time to
FunctionSideEffects. We have the flexibility of computing different
kinds of function effects at different points in the pipeline.
In the case of AccessedStorageAnalysis, it will compute both
FunctionSideEffects and FunctionAccessedStorage in the same pass by
implementing a simple wrapper on top of FunctionEffects.
This cleanup reflects my feeling that nested classes make the code
extremely unreadable unless they are very small and either private or
only used directly via its parent class. It's easier to see how these
classes compose with a flat type system.
In addition to enabling new kinds of function effects analyses, I
think this makes the implementation of side effect analysis easier to
understand by separating concerns.
As a first step to getting mandatory inlining out of the business
of 'linking' (walking the function graph and deserializing all
referenced functions), add a new optimizer pass which links
everything in the mandatory pipeline.
For now this is mostly NFC, except it regresses an optimization
I made recently by linking in bodies of methods of deserialized
vtables eagerly. This will be addressed in upcoming patches.
As a first step to getting mandatory inlining out of the business
of 'linking' (walking the function graph and deserializing all
referenced functions), add a new optimizer pass which links
everything in the mandatory pipeline.
For now this is mostly NFC, except it regresses an optimization
I made recently by linking in bodies of methods of deserialized
vtables eagerly. This will be addressed in upcoming patches.
To replace the code in DI and eventually remove PostponedCleanup in a
follow-up.
When SILGen emits ``convert_escape_to_noescape [not_guaranteed]
%operand`` instructions it assumes that a later SIL pass (this pass)
comes along and inserts retain_value/release_value instructions such that
the lifetime of the operand for the duration of the trivial closure
result.
This commit introduces the pass but does not yet use it.
The EscapeAnalysis:canEscapeTo function was actually broken, because it did not detect all escapes of a reference/pointer.
I completely replaced the implementation with the correct one (canObjectOrContentEscapeTo) and removed the now obsolete canObjectOrContentEscapeTo.
Fixes a miscompile.
rdar://problem/39161309
It was only used in a few tests. Those tests now use -emit-sil instead
of -emit-silgen, with some functions marked @_transparent and a few
CHECK: lines changed now that the mandatory optimizations get to run.
I am getting rid of FunctionSignatureOptUtils. It is only used by
FunctionSignatureOpts, so it should either be a local utility file whose header
lives in ./lib or integrated into FunctionSignatureOpts. Beyond this utility
function (which seems like a generally useful thing that should be in
DebugUtils), the only other thing left in FunctionSignatureOptUtils is part of
the heuristic of FunctionSignatureOpts. It should really be in that file.
rdar://38196046
Add a new warning that detects when a function will call itself
recursively on all code paths. Attempts to invoke functions like this
may cause unbounded stack growth at least or undefined behavior in the
worst cases.
The detection code is implemented as DFS for a reachable exit path in
a given SILFunction.
The devirtualizer performs two optimizations:
- If a value is known to have an exact class type, ie it is the result of an alloc_ref, we can devirtualize calls of *non-final* methods, because we know we’re calling that specific method and not an override.
- If a method is known to be “effectively final” (it is not open, and there are no overrides inside the module) we can devirtualize it.
However the second optimization needs to be disabled if a function is inlinable (F->getResilienceExpansion() == ResilienceExpansion::Minimal).
We want as few module passes as possible.
Function passes allow the PassManager to do its job.
e.g. it can filter certain functions that should not be applied to the
current pipeline. This will result in less work in the pass itself and
fewer pass manager related bugs.
Function passes are easier to understand and debug in the context of the
pipeline. Things like PrettyStackTrace are handled automatically.
Bisecting functionality is builtin.
Function passes are more compatible in general with inter-procedural
analysis.
Function passes are more efficient.
A single module pass in the middle of the pipeline destroys the benefit
of the rest of the pipeline uses function passes.
Create helpers in InstructionUtils.h wherever we need a guarantee that the diagnostics cover the same patterns as the verifier. Eventually this will be called from both SILVerifier and the diagnostic pass:
- findAccessedAddressBase
- isPossibleFormalAccessBase
- isPartialApplyOfReabstractionThunk
- findClosureForAppliedArg
- visitAccessedAddress
Add partial_apply verification assert.
This applies the normal "find a closure" logic inside the "find all partial_apply uses" verification. Making the verifier round-trip ensures that we don't have holes in exclusivity enforcement related to this logic.