Reland "[NFC] SimplifyCFG: refactor/deduplicate command-line settings override handling"

Initially i forgot to stage the SimplifyCFGPass::SimplifyCFGPass() change
to actually take the passed params..

Revert "[NFC] SimplifyCFG: refactor/deduplicate command-line settings override handling"

Seems to be breaking the bots.
This reverts commit 740a1da108ab9097268b509c85ed9ede7f4d5df5.

[NFC] SimplifyCFG: refactor/deduplicate command-line settings override handling

Reland "[NFCI] createCFGSimplificationPass(): migrate to also take SimplifyCFGOptions"

This reverts commit 1067d3e176ea7b0b1942c163bf8c6c90107768c1,
which reverted commit b2018198c32a0535bb1f5bb5b40

Reland "[NFCI] createCFGSimplificationPass(): migrate to also take SimplifyCFGOptions"

This reverts commit 1067d3e176ea7b0b1942c163bf8c6c90107768c1,
which reverted commit b2018198c32a0535bb1f5bb5b40fbcf50d8d47b7,
because it introduced a Dependency Cycle between Transforms/Scalar and
Transforms/Utils.

So let's just move SimplifyCFGOptions.h into Utils/, thus avoiding
the cycle.

show more ...

Revert "[NFCI] createCFGSimplificationPass(): migrate to also take SimplifyCFGOptions"

This reverts commit b2018198c32a0535bb1f5bb5b40fbcf50d8d47b7.
This commit introduced a Dependency Cycle between

Revert "[NFCI] createCFGSimplificationPass(): migrate to also take SimplifyCFGOptions"

This reverts commit b2018198c32a0535bb1f5bb5b40fbcf50d8d47b7.
This commit introduced a Dependency Cycle between Transforms/Scalar and
Transforms/Utils. Transforms/Scalar already depends on Transforms/Utils,
so if SimplifyCFGOptions.h is moved to Scalar, and Utils/Local.h still
depends on it, we have a cycle.

show more ...

[NFCI] createCFGSimplificationPass(): migrate to also take SimplifyCFGOptions

Taking so many parameters is simply unmaintainable.

We don't want to include the entire llvm/Transforms/Utils/Local.h i

[NFCI] createCFGSimplificationPass(): migrate to also take SimplifyCFGOptions

Taking so many parameters is simply unmaintainable.

We don't want to include the entire llvm/Transforms/Utils/Local.h into
llvm/Transforms/Scalar.h so i've split SimplifyCFGOptions into
it's own header.

show more ...

[NFCI] CFGSimplifyPass: change (the only) constructor to take SimplifyCFGOptions

Taking that long list of parameters is already simply unmaintainable.

SimplifyCFG: Clean up optforfuzzing implementation

This should function as any other SimplifyCFGOption rather than having
the transform check and specially consider the attribute itself.

[SimplifyCFG] Skip merging return blocks if it would break a CallBr.

SimplifyCFG should not merge empty return blocks and leave a CallBr behind
with a duplicated destination since the verifier will

[SimplifyCFG] Skip merging return blocks if it would break a CallBr.

SimplifyCFG should not merge empty return blocks and leave a CallBr behind
with a duplicated destination since the verifier will then trigger an
assert. This patch checks for this case and avoids the transformation.

CodeGenPrepare has a similar check which also has a FIXME comment about why
this is needed. It seems perhaps better if these two passes would eventually
instead update the CallBr instruction instead of just checking and avoiding.

This fixes https://bugs.llvm.org/show_bug.cgi?id=45062.

Review: Craig Topper

Differential Revision: https://reviews.llvm.org/D75620

show more ...

Sink all InitializePasses.h includes

This file lists every pass in LLVM, and is included by Pass.h, which is
very popular. Every time we add, remove, or rename a pass in LLVM, it
caused lots of reco

Sink all InitializePasses.h includes

This file lists every pass in LLVM, and is included by Pass.h, which is
very popular. Every time we add, remove, or rename a pass in LLVM, it
caused lots of recompilation.

I found this fact by looking at this table, which is sorted by the
number of times a file was changed over the last 100,000 git commits
multiplied by the number of object files that depend on it in the
current checkout:
recompiles touches affected_files header
342380 95 3604 llvm/include/llvm/ADT/STLExtras.h
314730 234 1345 llvm/include/llvm/InitializePasses.h
307036 118 2602 llvm/include/llvm/ADT/APInt.h
213049 59 3611 llvm/include/llvm/Support/MathExtras.h
170422 47 3626 llvm/include/llvm/Support/Compiler.h
162225 45 3605 llvm/include/llvm/ADT/Optional.h
158319 63 2513 llvm/include/llvm/ADT/Triple.h
140322 39 3598 llvm/include/llvm/ADT/StringRef.h
137647 59 2333 llvm/include/llvm/Support/Error.h
131619 73 1803 llvm/include/llvm/Support/FileSystem.h

Before this change, touching InitializePasses.h would cause 1345 files
to recompile. After this change, touching it only causes 550 compiles in
an incremental rebuild.

Reviewers: bkramer, asbirlea, bollu, jdoerfert

Differential Revision: https://reviews.llvm.org/D70211

show more ...

Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the ne

Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636

show more ...

Move Analysis/Utils/Local.h back to Transforms

Review feedback from r328165. Split out just the one function from the
file that's used by Analysis. (As chandlerc pointed out, the original
change onl

Move Analysis/Utils/Local.h back to Transforms

Review feedback from r328165. Split out just the one function from the
file that's used by Analysis. (As chandlerc pointed out, the original
change only moved the header and not the implementation anyway - which
was fine for the one function that was used (since it's a
template/inlined in the header) but not in general)

llvm-svn: 333954

show more ...

Fix a couple of layering violations in Transforms

Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering.

Transforms depends on Transforms/Utils, not the other way around. So
r

Fix a couple of layering violations in Transforms

Remove #include of Transforms/Scalar.h from Transform/Utils to fix layering.

Transforms depends on Transforms/Utils, not the other way around. So
remove the header and the "createStripGCRelocatesPass" function
declaration (& definition) that is unused and motivated this dependency.

Move Transforms/Utils/Local.h into Analysis because it's used by
Analysis/MemoryBuiltins.cpp.

llvm-svn: 328165

show more ...

[SimplifyCFG] don't sink common insts too soon (PR34603)

This should solve:
https://bugs.llvm.org/show_bug.cgi?id=34603
...by preventing SimplifyCFG from altering redundant instructions before early

[SimplifyCFG] don't sink common insts too soon (PR34603)

This should solve:
https://bugs.llvm.org/show_bug.cgi?id=34603
...by preventing SimplifyCFG from altering redundant instructions before early-cse has a chance to run.
It changes the default (canonical-forming) behavior of SimplifyCFG, so we're only doing the
sinking transform later in the optimization pipeline.

Differential Revision: https://reviews.llvm.org/D38566

llvm-svn: 320749

show more ...

[SimplifyCFG] use pass options and remove the latesimplifycfg pass

This is no-functional-change-intended.

This is repackaging the functionality of D30333 (defer switch-to-lookup-tables) and
D35411

[SimplifyCFG] use pass options and remove the latesimplifycfg pass

This is no-functional-change-intended.

This is repackaging the functionality of D30333 (defer switch-to-lookup-tables) and
D35411 (defer folding unconditional branches) with pass parameters rather than a named
"latesimplifycfg" pass. Now that we have individual options to control the functionality,
we could decouple when these fire (but that's an independent patch if desired).

The next planned step would be to add another option bit to disable the sinking transform
mentioned in D38566. This should also make it clear that the new pass manager needs to
be updated to limit simplifycfg in the same way as the old pass manager.

Differential Revision: https://reviews.llvm.org/D38631

llvm-svn: 316835

show more ...

[SimplifyCFG] delay switch condition forwarding to -latesimplifycfg

As discussed in D39011:
https://reviews.llvm.org/D39011
...replacing constants with a variable is inverting the transform done
by

[SimplifyCFG] delay switch condition forwarding to -latesimplifycfg

As discussed in D39011:
https://reviews.llvm.org/D39011
...replacing constants with a variable is inverting the transform done
by other IR passes, so we definitely don't want to do this early.
In fact, it's questionable whether this transform belongs in SimplifyCFG
at all. I'll look at moving this to codegen as a follow-up step.

llvm-svn: 316298

show more ...

[SimplifyCFG] put the optional assumption cache pointer in the options struct; NFCI

This is a follow-up to https://reviews.llvm.org/D38138.

I fixed the capitalization of some functions because we'

[SimplifyCFG] put the optional assumption cache pointer in the options struct; NFCI

This is a follow-up to https://reviews.llvm.org/D38138.

I fixed the capitalization of some functions because we're changing those
lines anyway and that helped verify that we weren't accidentally dropping
any options by using default param values.

llvm-svn: 314930

show more ...

[SimplifyCFG] add a struct to house optional folds (PR34603)

This was intended to be no-functional-change, but it's not - there's a test diff.

So I thought I should stop here and post it as-is to s

[SimplifyCFG] add a struct to house optional folds (PR34603)

This was intended to be no-functional-change, but it's not - there's a test diff.

So I thought I should stop here and post it as-is to see if this looks like what was expected
based on the discussion in PR34603:
https://bugs.llvm.org/show_bug.cgi?id=34603

Notes:
1. The test improvement occurs because the existing 'LateSimplifyCFG' marker is not carried
through the recursive calls to 'SimplifyCFG()->SimplifyCFGOpt().run()->SimplifyCFG()'.
The parameter isn't passed down, so we pick up the default value from the function signature
after the first level. I assumed that was a bug, so I've passed 'Options' down in all of the
'SimplifyCFG' calls.

2. I split 'LateSimplifyCFG' into 2 bits: ConvertSwitchToLookupTable and KeepCanonicalLoops.
This would theoretically allow us to differentiate the transforms controlled by those params
independently.

3. We could stash the optional AssumptionCache pointer and 'LoopHeaders' pointer in the struct too.
I just stopped here to minimize the diffs.

4. Similarly, I stopped short of messing with the pass manager layer. I have another question that
could wait for the follow-up: why is the new pass manager creating the pass with LateSimplifyCFG
set to true no matter where in the pipeline it's creating SimplifyCFG passes?

// Create an early function pass manager to cleanup the output of the
// frontend.
EarlyFPM.addPass(SimplifyCFGPass());

-->

/// \brief Construct a pass with the default thresholds
/// and switch optimizations.
SimplifyCFGPass::SimplifyCFGPass()
: BonusInstThreshold(UserBonusInstThreshold),
LateSimplifyCFG(true) {} <-- switches get converted to lookup tables and loops may not be in canonical form

If this is unintended, then it's possible that the current behavior of dropping the 'LateSimplifyCFG'
setting via recursion was masking this bug.

Differential Revision: https://reviews.llvm.org/D38138

llvm-svn: 314308

show more ...

Split the SimplifyCFG pass into two variants.

The first variant contains all current transformations except
transforming switches into lookup tables. The second variant
contains all current transfor

Split the SimplifyCFG pass into two variants.

The first variant contains all current transformations except
transforming switches into lookup tables. The second variant
contains all current transformations.

The switch-to-lookup-table conversion results in code that is more
difficult to analyze and optimize by other passes. Most importantly,
it can inhibit Dead Code Elimination. As such it is often beneficial to
only apply this transformation very late. A common example is inlining,
which can often result in range restrictions for the switch expression.

Changes in execution time according to LNT:
SingleSource/Benchmarks/Misc/fp-convert +3.03%
MultiSource/Benchmarks/ASC_Sequoia/CrystalMk/CrystalMk -11.20%
MultiSource/Benchmarks/Olden/perimeter/perimeter -10.43%
and a couple of smaller changes. For perimeter it also results 2.6%
a smaller binary.

Differential Revision: https://reviews.llvm.org/D30333

llvm-svn: 298799

show more ...

Revert @llvm.assume with operator bundles (r289755-r289757)

This creates non-linear behavior in the inliner (see more details in
r289755's commit thread).

llvm-svn: 290086

Remove the AssumptionCache

After r289755, the AssumptionCache is no longer needed. Variables affected by
assumptions are now found by using the new operand-bundle-based scheme. This
new scheme is mo

Remove the AssumptionCache

After r289755, the AssumptionCache is no longer needed. Variables affected by
assumptions are now found by using the new operand-bundle-based scheme. This
new scheme is more computationally efficient, and also we need much less
code...

llvm-svn: 289756

show more ...

Consistently use FunctionAnalysisManager

Besides a general consistently benefit, the extra layer of indirection
allows the mechanical part of https://reviews.llvm.org/D23256 that
requires touching e

Consistently use FunctionAnalysisManager

Besides a general consistently benefit, the extra layer of indirection
allows the mechanical part of https://reviews.llvm.org/D23256 that
requires touching every transformation and analysis to be factored out
cleanly.

Thanks to David for the suggestion.

llvm-svn: 278077

show more ...

Move instances of std::function.

Or replace with llvm::function_ref if it's never stored. NFC intended.

llvm-svn: 272513

[PM/SimplifyCFG] Preserve GlobalsAA even if the IR is mutated.

llvm-svn: 272139

Apply clang-tidy's misc-move-constructor-init throughout LLVM.

No functionality change intended, maybe a tiny performance improvement.

llvm-svn: 270997