Teach dominator based simplifications to also thread dominated edges.
The code now handles cond_br and switch_enum terminators for both value based
simplifications (where the use is dominated) and jump threading edges (the edge
is dominated).
Update simplify_cfg.sil test cases for split edges.
This also handles the test case from rdar://20390647.
Swift SVN r27843
This reverts commit r27739 reapplying r27722.
The test (validation/stdlib/Hashing.swift) that failed is expected to sometimes
fails.
Original message
"SimplifyCFG: Fix a bug in the jump threading code
When jump threading a block we used to propagate phi values directly into the
threaded block - instead of leaving in a copy. Because of this the SSA updater
would propagate the value feeding the copy from the next iteration.
Now when jump threading the destination block into the edge we leave in the phi
(copy) such that the SSA updater picks up value of the right iteration.
rdar://20617338"
Swift SVN r27741
When jump threading a block we used to propagate phi values directly into the
threaded block - instead of leaving in a copy. Because of this the SSA updater
would propagate the value feeding the copy from the next iteration.
Now when jump threading the destination block into the edge we leave in the phi
(copy) such that the SSA updater picks up value of the right iteration.
rdar://20617338
Swift SVN r27722
This updates the performance inliner to iterate on inlining in cases
where devirtualization or specialization after the first pass of
inlining expose new opportunities for inlining. Similarly, in some cases
inlining exposes new opportunities for devirtualization, e.g. when we
inline an initializer and can now see an alloc_ref that allows us to
devirtualize some class_methods.
The implementation currently has some inefficiencies which increase the
swift compilation time for the stdlib by around 3% (this is swift-time
only, no LLVM time, so overall time does not grow by this much).
Unfortunately the (unchanged) current implementation of the core
inlining trades off improved estimates of code growth for increased
compile time, and that plays a part in why compile time increases as
much as it does. Despite this, I have some ideas on how to win some of
that time back in future patches.
Performance differences are mixed, and this will likely require some
further inliner tuning to reduce or remove some of the losses seen here
at -O. I will open radars for the losses.
Wins:
DeltaBlue 10.2%
EditDistance 13.8%
SwiftStructuresInsertionSort 32.6%
SwiftStructuresStack 34.9%
Losses:
PopFrontArrayGeneric -12.7%
PrimeNum -19.0%
RC4 -30.7%
Sim2DArray -14.6%
There were a handful of wins and losses at Onone and Ounchecked as
well. I'll review the perf testing output and open radars accordingly.
The new test case shows an example of the power of the closer
integration here. We are able to completely devirtualize and inline a
series of class_method applies (10 deep in this case, but in theory
substantially deeper) in a single pass of the inliner, whereas before we
could only do a single level per pass of inlining & devirtualization.
Swift SVN r27561
If a conformance to _BridgedToObjectiveC is statically known, generate a more efficient code by using the newly introduced library functions for bridging casts.
This covers the casts resulting from SIL optimizations.
Tests are included. I tried to cover most typical casts from ObjC types into Swift types and vice versa and to check that we always generate something more efficient than a checked_cast or unconditional_checked_cast. But probably even more tests should be written or generated by means of gyb files to make sure that nothing important is missing.
The plan is to make the bridged casts SIL optimization a guaranteed optimization. Once it is done, there is no need to lower the bridged casts in a special way inside Sema, because they all can be handled by the optimizer in a uniform way. This would apply to bridging of Error types too.
With this change, no run-time conformance checks are performed at run-time if conformances are statically known at compile-time.
As a result, the performance of rdar://19081345 is improved by about 15%. In the past, conformance checks in this test took 50% of its execution time, then after some improvements 15% and now it is 0%, as it should be.
Swift SVN r27102
If someone has conflicting changes, please feel free to revert this,
commit your changes, and then do the same unindenting of the resulting
file as a separate step.
Swift SVN r26819
threaded into IRGen; tests to follow when that's done.
I made a preliminary effort to make the inliner do the
right thing with try_apply, but otherwise tried to avoid
touching the optimizer any more than was required by the
removal of ApplyInstBase.
Swift SVN r26747
Use existing machinery of the generic specializer to produce generic specializations of closures referenced by partial_apply instructions. Thanks to the newly introduced ApplyInstBase class, the required changes in the generic specializer are very minimal.
rdar://19290942
Swift SVN r26582
This is mostly a re-factoring. It creates a new helper class CastOptimizer which contains all the logic for performing type casts optimizations. This logic is a copy of the current logic from sil-combine and simplify-cfg. Those passes will become clients of this new helper class.
Swift SVN r26122
In every instance, we were just creating the StringConcatenationOptimizer and
then invoking optimize on it. This is a cleaner solution since the details of
how we perform the string concatenation are hidden in Local.cpp instead of being
in a header.
NFC.
Swift SVN r25341
This refactors some code out of AllocBoxToStack that computes the
lifetime of a value in the strictess sense, limiting the lifetime to
that value and not anything derived from that value (whether by casting,
projection, etc.).
In the short term this will be used to fix a very rarely hit
optimization in AllocBoxToStack.
Longer term I will replace the other similar code in AllocBoxToStack to
use this instead.
Swift SVN r25176
This utility attempts to delete dead closures with a set of
post-dominating releases using the infrastructure from
getFinalReleasesForValue.
It currently only will eliminate closures that only have retain, release
uses and a final post-dominating release set.
The reason why we need the final post-dominating release set is so that
we can release any captured variables at the points where we would have
deallocated the release. This is b/c captured variables are passed in at
+1 to partial apply.
Swift SVN r25050
Array.init does not have a self argument (it returns the newly created array
@owned). Passes using the ArraySemantic::getSelf() interface must handle it
specially.
rdar://19724033
Swift SVN r25013
In order to not completely loose testcoverage while rdar://problem/18709125
is under investiagtion, add a special flag for enabling debug value
liveness.
Patch by Michael Gottesman!
<rdar://problem/19267059>
Swift SVN r24416
It had exposed a problem with the MemBehavior on a couple SIL
instructions which resulted in code motion moving a retain across an
instruction that can release (fixed in r23722).
From the original commit message:
Remove restriction on substituting existentials during mandatory inlining.
Issues around this have now been resolved, so we should now support
anything that Sema lets through.
Fixes rdar://problem/17769717.
Swift SVN r23729
"array.props.isCocoa/needsElementTypeCheck" semantic calls will mark calls that
return array properties: isCocoa and needsElementTypeCheck. We know that said
states can only transfer in certain directions (a native swift array that does
not need an element type check stays in this state) enabling us to version loops
based on the state of said array array properties.
rdar://17955309
Swift SVN r23688
I also extracted out an additional method clearBlockBody() from the body
of removeDeadBlocks() since I need that functionality exposed in
Function Signature Opts.
Swift SVN r22560
This encapsulates common operations on array semantic calls like identifying
them or hoisting/copying them.
Will be used by follow-up commits. NFC.
Swift SVN r21926
This will hopefully make it clearer as we onboard people that
SimplifyInstruction should not add instructions to the IR by making it clearer
that it is an analysis, not a pass.
Swift SVN r21752
This looks for @effects(readnone) on functions. A follow up commit will mark
_swift_isClassOrObjCExistential as readnone allowing us to CSE it.
rdar://17961249
Swift SVN r21285
