To do so this commit does a few different things:
1. I changed SILOptFunctionBuilder to notify the pass manager's logging
functionality when new functions are added to the module and to notify analyses
as well. NOTE: This on purpose does not put the new function on the pass manager
worklist since we do not want to by mistake introduce a large amount of
re-optimizations. Such a thing should be explicit.
2. I eliminated SILModuleTransform::notifyAddFunction. This just performed the
operations from 1. Now that SILOptFunctionBuilder performs this operation for
us, it is not needed.
3. I changed SILFunctionTransform::notifyAddFunction to just add the function to
the passmanager worklist. It does not need to notify the pass manager's logging
or analyses that a new function was added to the module since
SILOptFunctionBuilder now performs that operation. Given its reduced
functionality, I changed the name to addFunctionToPassManagerWorklist(...). The
name is a little long/verbose, but this is a feature since one should think
before getting the pass manager to rerun transforms on a function. Also, giving
it a longer name calls out the operation in the code visually, giving this
operation more prominance when reading code. NOTE: I did the rename using
Xcode's refactoring functionality!
rdar://42301529
I am going to add the code in a bit that does the notifications. I tried to pass
down the builder instead of the pass manager. I also tried not to change the
formatting.
rdar://42301529
This name makes it clear that the function has not yet been deleted and also
contrasts with the past tense used in the API notifyAddedOrModifiedFunction to
show that said function has already added/modified the function.
The name notifyAddFunction is actively harmful since the pass manager uses this
entrypoint to notify analyses of added *OR* modified functions. It is up to the
caller analysis to distinguish in between these cases.
I am not vouching for the design, just trying to make names match the
current behavior.
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.
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
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
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.
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.
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.
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.
We run GlobalOpt multiple times in the pass pipeline but in some cases object outlining shouldn't be done too early.
Having it done in a separate pass enables to run it independently from GlobalOpt.
We run GlobalOpt multiple times in the pass pipeline but in some cases object outlining shouldn't be done too early.
Having it done in a separate pass enables to run it independently from GlobalOpt.
* rename "Name" to "Description" in the pass definition, because it's not really the pass name, but the description of a pass
* remove the getName() from Transforms (which actually returned the description of a pass)
* in debug printing, print the pass ID and not the pass description. It makes it easier to correlate the debug output to the actual pass implementation.
* remove the iteration numbering in the pass manager, because we only run a single iteration anyway.
This commit is mostly refactoring.
*) Introduce a new OptimizationMode enum and use that in SILOptions and IRGenOptions
*) Allow the optimization mode also be specified for specific SILFunctions. This is not used in this commit yet and thus still a NFC.
Also, fixes a minor bug: we didn’t run mandatory IRGen passes for functions with @_semantics("optimize.sil.never")
Recent changes that eliminated the -sil-serialize-all mode and adding this check to IRGen allow us to get rid of ExternalFunctionDefinitionsElimination and ExternalDefsToDecls passes, which are not needed anymore.
This patch implements collection and dumping of statistics about SILModules, SILFunctions and memory consumption during the execution of SIL optimization pipelines.
The following statistics can be collected:
* For SILFunctions: the number of SIL basic blocks, the number of SIL instructions, the number of SIL instructions of a specific kind, duration of a pass
* For SILModules: the number of SIL basic blocks, the number of SIL instructions, the number of SIL instructions of a specific kind, the number of SILFunctions, the amount of memory used by the compiler, duration of a pass
By default, any collection of statistics is disabled to avoid affecting compile times.
One can enable the collection of statistics and dumping of these statistics for the whole SILModule and/or for SILFunctions.
To reduce the amount of produced data, one can set thresholds in such a way that changes in the statistics are only reported if the delta between the old and the new values are at least X%. The deltas are computed as using the following formula:
Delta = (NewValue - OldValue) / OldValue
Thresholds provide a simple way to perform a simple filtering of the collected statistics during the compilation. But if there is a need for a more complex analysis of collected data (e.g. aggregation by a pipeline stage or by the type of a transformation), it is often better to dump as much data as possible into a file using e.g. -sil-stats-dump-all -sil-stats-modules -sil-stats-functions and then e.g. use the helper scripts to store the collected data into a database and then perform complex queries on it. Many kinds of analysis can be then formulated pretty easily as SQL queries.
This is a separate optimization that detects short-lived temporaries that can be eliminated.
This is necessary now that SILGen no longer performs basic RValue forwarding in some cases.
SR-5508: Performance regression in benchmarks caused by removing SILGen peephole for LoadExpr in +0 context
The problem here is that we were performing a naive negative FileCheck test for
retain/release. In certain modes, we would not have any retains/releases along
normal control paths but would have retains on unreachable paths. This test only
is trying to test if normal code paths have this issue.
To work around this issue, I created a small utility pass that prunes all
non-unreachable instructions from blocks with an unreachable terminator. This is
useful functionality in general when analyzing SIL since often times one will
have large fatal error blocks that disguise the true behavior of the
function. In this specific case, I just pipe in the normal sil output and run it
through sil-opt. sil-opt then runs just the utility pass and I then FileCheck
that sil-opt output.
rdar://30181104
A pass has an ID (C++ identifier), Tag (shell identifier),
and Name (human identifier).
Command line options that identify passes should obviously be compatibile with
with the pass' command line identifier. This is also what the user is used to
typing for the -debug-only option.
In raw SIL, access markers are unconditionally retained. In canonical SIL,
markers are still removed prior to optimization.
A new flag, -sil-optimized-access-markers, allows testing access markers in
optimized builds, but it is not yet fully supported.
Add an interprocedural SIL analysis pass that summarizes the accesses that
closures make on their @inout_aliasable captures. This will be used to
statically enforce exclusivity for calls to functions that take noescape
closures.
The analysis summarizes the accesses on each argument independently and
uses the BottomUpIPAnalysis utility class to iterate to a fixed point when
there are cycles in the call graph.
For now, the analysis is not stored-property-sensitive -- that will come in a
later commit.
Replace `NameOfType foo = dyn_cast<NameOfType>(bar)` with DRY version `auto foo = dyn_cast<NameOfType>(bar)`.
The DRY auto version is by far the dominant form already used in the repo, so this PR merely brings the exceptional cases (redundant repetition form) in line with the dominant form (auto form).
See the [C++ Core Guidelines](https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#es11-use-auto-to-avoid-redundant-repetition-of-type-names) for a general discussion on why to use `auto` to avoid redundant repetition of type names.
I put in a simple fixup pass (MarkUninitializedFixup) for staging purposes. I
don't expect it to be in tree long. I just did not feel comfortable fixing up in
1 commit all of the passes up to DI.
rdar://31521023
