Commit Graph

265 Commits

Author SHA1 Message Date
Yaxun (Sam) Liu 9d5adc7e49 Revert "reland e5581df60a [SimplifyCFG] accumulate bonus insts cost"
This reverts commit bd7949bcd8.

Revert this patch since reviwers have different opinions regarding
the approach in post-commit review.

Will open RFC for further discussion.

Differential Revision: https://reviews.llvm.org/D132408
2022-10-25 12:15:39 -04:00
Yaxun (Sam) Liu bd7949bcd8 reland e5581df60a [SimplifyCFG] accumulate bonus insts cost
Fixed compile time increase due to always constructing LocalCostTracker.
Now only construct LocalCostTracker when needed.
2022-10-24 15:43:53 -04:00
Florian Hahn 16cf666bb7
[Loop] Move block and loop dispo invalidation to makeLoopInvariant.
makeLoopInvariant may recursively move its operands to make them
invariant, before moving the passed in instruction. Those recursively
moved instructions are currently missed when invalidating block and loop
dispositions.

To address this, move the invalidation code to Loop::makeLoopInvariant.

Fixes #58314.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D135909
2022-10-14 21:58:14 +01:00
Florian Hahn 19ad1cd5ce
Recommit "[SCEV] Support clearing Block/LoopDispositions for a single value."
This reverts commit 92f698f01f.

The updated version of the patch includes handling for non-SCEVable
types. A test case has been added in ec86e9a99b.
2022-10-07 20:15:44 +01:00
Florian Hahn 92f698f01f
Revert "[SCEV] Support clearing Block/LoopDispositions for a single value."
This reverts commit 9e931439dd.

This commit causes a crash when TSan, e.g. with
https://lab.llvm.org/buildbot/#/builders/70/builds/28309/steps/10/logs/stdio

Reverting while I extract a reproducer and submit a fix.
2022-10-07 17:58:54 +01:00
Florian Hahn 9e931439dd
[SCEV] Support clearing Block/LoopDispositions for a single value.
Extend forgetBlockAndLoopDisposition to allow clearing information for a
single value. This can be useful when only a single value is changed,
e.g. because the instruction is moved.

We also need to clear the cached values for all SCEV users, because they
may depend on the starting value's disposition.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D134614
2022-10-07 16:07:17 +01:00
Nikita Popov dd61726d5b Revert "[SimplifyCFG] accumulate bonus insts cost"
This reverts commit e5581df60a.

This causes major compile-time regressions, about 2-3% end-to-end
on CTMark.
2022-09-19 14:46:43 +02:00
Max Kazantsev 818b1ab84e [SCEV][NFC] Remove unused parameter from forgetLoopDispositions
Let's be honest about it, we don't drop loop dispositions for
particular loops. Remove the parameter that misleadingly makes
it apparent that we do.
2022-09-19 14:06:42 +07:00
Yaxun (Sam) Liu e5581df60a [SimplifyCFG] accumulate bonus insts cost
SimplifyCFG folds

bool foo() {
  if (cond1) return false;
  if (cond2) return false;
  return true;
}

as

bool foo() {
  if (cond1 | cond2) return false
  return true;
}

'cond2' is called 'bonus insts' in branch folding since they introduce overhead
since the original CFG could do early exit but the folded CFG always executes
them. SimplifyCFG calculates the costs of 'bonus insts' of a folding a BB into
its predecessor BB which shares the destination. If it is below bonus-inst-threshold,
SimplifyCFG will fold that BB into its predecessor and cond2 will always be executed.

When SimplifyCFG calculates the cost of 'bonus insts', it only consider 'bonus' insts
in the current BB to be considered for folding. This causes issue for unrolled loops
which share destinations, e.g.

bool foo(int *a) {
  for (int i = 0; i < 32; i++)
    if (a[i] > 0) return false;
  return true;
}

After unrolling, it becomes

bool foo(int *a) {
  if(a[0]>0) return false
  if(a[1]>0) return false;
  //...
  if(a[31]>0) return false;
  return true;
}

SimplifyCFG will merge each BB with its predecessor BB,
and ends up with 32 'bonus insts' which are always executed, which
is much slower than the original CFG.

The root cause is that SimplifyCFG does not consider the
accumulated cost of 'bonus insts' which are folded from
different BB's.

This patch fixes that by introducing a ValueMap to track
costs of 'bonus insts' coming from different BB's into
the same BB, and cuts off if the accumulated cost
exceeds a threshold.

Reviewed by: Artem Belevich, Florian Hahn, Nikita Popov, Matt Arsenault

Differential Revision: https://reviews.llvm.org/D132408
2022-09-18 20:21:14 -04:00
Kazu Hirata b18ff9c461 [Transform] Use range-based for loops (NFC) 2022-08-27 23:54:32 -07:00
Kazu Hirata 56ea4f9bd3 [Transforms] Qualify auto in range-based for loops (NFC)
Identified with readability-qualified-auto.
2022-08-27 21:21:02 -07:00
Nikita Popov 11079e8820 [IR] Don't treat callbr as indirect terminator
Callbr is no longer an indirect terminator in the sense that is
relevant here (that it's successors cannot be updated). The primary
effect of this change is that callbr no longer prevents formation
of loop simplify form.

I decided to drop the isIndirectTerminator() method entirely and
replace it with isa<IndirectBrInst>() checks. I assume this method
was added to abstract over indirectbr and callbr, but it never
really caught on, and there is nothing left to abstract anymore
at this point.

Differential Revision: https://reviews.llvm.org/D129849
2022-07-18 09:32:08 +02:00
Simon Moll b8c2781ff6 [NFC] format InstructionSimplify & lowerCaseFunctionNames
Clang-format InstructionSimplify and convert all "FunctionName"s to
"functionName".  This patch does touch a lot of files but gets done with
the cleanup of InstructionSimplify in one commit.

This is the alternative to the less invasive clang-format only patch: D126783

Reviewed By: spatel, rengolin

Differential Revision: https://reviews.llvm.org/D126889
2022-06-09 16:10:08 +02:00
serge-sans-paille a494ae43be Cleanup includes: TransformsUtils
Estimation on the impact on preprocessor output:
before: 1065307662
after:  1064800684

Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D120741
2022-03-01 21:00:07 +01:00
Kazu Hirata d1abf481da [llvm] Use range-based for loops (NFC) 2021-11-19 21:12:13 -08:00
Nikita Popov 735a590471 [MemorySSA] Remove -enable-mssa-loop-dependency option
This option has been enabled by default for quite a while now.
The practical impact of removing the option is that MSSA use
cannot be disabled in default pipelines (both LPM and NPM) and
in manual LPM invocations. NPM can still choose to enable/disable
MSSA using loop vs loop-mssa.

The next step will be to require MSSA for LICM and drop the
AST-based implementation entirely.

Differential Revision: https://reviews.llvm.org/D108075
2021-08-16 20:59:37 +02:00
Johannes Doerfert 25a3130d89 [Local] Do not introduce a new `llvm.trap` before `unreachable`
This is the second attempt to remove the `llvm.trap` insertion after
https://reviews.llvm.org/rGe14e7bc4b889dfaffb7180d176a03311df2d4ae6
reverted the first one. It is not clear what the exact issue was back
then and it might already be gone by now, it has been >5 years after
all.

Replaces D106299.

Differential Revision: https://reviews.llvm.org/D106308
2021-07-26 23:33:36 -05:00
Arthur Eubanks 6b9524a05b [NewPM] Don't mark AA analyses as preserved
Currently all AA analyses marked as preserved are stateless, not taking
into account their dependent analyses. So there's no need to mark them
as preserved, they won't be invalidated unless their analyses are.

SCEVAAResults was the one exception to this, it was treated like a
typical analysis result. Make it like the others and don't invalidate
unless SCEV is invalidated.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D102032
2021-05-18 13:49:03 -07:00
Kazu Hirata be23012d5a [Transforms/Utils] Use range-based for loops (NFC) 2021-02-07 09:49:36 -08:00
Kazu Hirata e53472de68 [Transforms] Use llvm::append_range (NFC) 2021-01-20 21:35:54 -08:00
Roman Lebedev c043f5055e
[SimplifyCFG] Teach FoldBranchToCommonDest() to preserve DomTree, part 1
... for conditional branch case
2020-12-20 00:18:36 +03:00
Kazu Hirata 1da60f1d44 [Transforms] Use pred_empty (NFC) 2020-11-16 22:09:14 -08:00
Pedro Tammela 70a495c7f0 [NFC][LoopSimplify] modernize for loops over LoopInfo
This patch modifies two for loops to use the range based syntax.
Since they are equivalent, this patch is tagged NFC.

Differential Revision: https://reviews.llvm.org/D90069
2020-10-30 16:50:07 +00:00
Benjamin Kramer 44ab60f74d [LoopSimplify] Use SmallPtrSet and range for loops more. NFCI. 2020-07-20 15:00:59 +02:00
Nicolai Hähnle 76c5cb05a3 DomTree: Remove getChildren() accessor
Summary:
Avoid exposing details about how children are stored. This will enable
subsequent type-erasure changes.

New methods are introduced to cover common access patterns.

Change-Id: Idb5f4b1b9c84e4cc71ddb39bb52a388682f5674f

Reviewers: arsenm, RKSimon, mehdi_amini, courbet

Subscribers: qcolombet, sdardis, wdng, hiraditya, jrtc27, zzheng, atanasyan, asbirlea, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D83083
2020-07-06 21:58:11 +02:00
serge-sans-paille 2e5940cf29 Correctly report modified status for LoopSimplify
Differential Revision: https://reviews.llvm.org/D81235
2020-06-05 15:46:28 +02:00
Sameer Sahasrabuddhe 6c84884366 [LoopSimplify] don't separate nested loops with convergent calls
Summary:
When a loop has multiple backedges, loop simplification attempts to
separate them out into nested loops. This results in incorrect control
flow in the presence of some functions like a GPU barrier. This change
skips the transformation when such "convergent" function calls are
present in the loop body.

Reviewed By: nhaehnle

Differential Revision: https://reviews.llvm.org/D80078
2020-05-19 09:22:39 +05:30
Reid Kleckner 05da2fe521 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
2019-11-13 16:34:37 -08:00
Jonas Devlieghere 0eaee545ee [llvm] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

llvm-svn: 369013
2019-08-15 15:54:37 +00:00
Alina Sbirlea 172838df6b [MemorySSA] Set LoopSimplify to preserve MemorySSA in the NPM, if analysis exists.
Summary:
LoopSimplify is preserved in the legacy pass manager, but not in the new pass manager.
Update LoopSimplify to preserve MemorySSA conditionally when the analysis is available (same behavior as the legacy pass manager).

Reviewers: chandlerc

Subscribers: mehdi_amini, jlebar, Prazek, george.burgess.iv, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65418

llvm-svn: 367594
2019-08-01 18:28:28 +00:00
Alina Sbirlea db101864bd [MemorySSA] Use SetVector to avoid nondeterminism.
Summary:
Use a SetVector for DeadBlockSet.
Resolves PR42574.

Reviewers: george.burgess.iv, uabelho, dblaikie

Subscribers: jlebar, Prazek, mgrang, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D64601

llvm-svn: 365970
2019-07-12 22:30:30 +00:00
Alina Sbirlea 80c6e79602 [MemorySSA] LoopSimplify preserves MemorySSA only when flag is flipped.
LoopSimplify can preserve MemorySSA after r360270.
But the MemorySSA analysis is retrieved and preserved only when the
EnableMSSALoopDependency is set to true. Use the same conditional to
mark the pass as preserved, otherwise subsequent passes will get an
invalid analysis.
Resolves PR41853.

llvm-svn: 360697
2019-05-14 18:07:18 +00:00
Alina Sbirlea f31eba6494 [MemorySSA] Teach LoopSimplify to preserve MemorySSA.
Summary:
Preserve MemorySSA in LoopSimplify, in the old pass manager, if the analysis is available.
Do not preserve it in the new pass manager.
Update tests.

Subscribers: nemanjai, jlebar, javed.absar, Prazek, kbarton, zzheng, jsji, llvm-commits, george.burgess.iv, chandlerc

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60833

llvm-svn: 360270
2019-05-08 17:05:36 +00:00
Roman Lebedev 7ad5d14f3a [NFC] Instruction: introduce replaceSuccessorWith() function, use it
Summary:
There is `Instruction::getNumSuccessors()`, `Instruction::getSuccessor()`
and `Instruction::setSuccessor()`, but no function to replace every
specified `BasicBlock*` successor with some other specified `BasicBlock*`.
I've found one place where it should clearly be used.

Reviewers: chandlerc, craig.topper, spatel, danielcdh

Reviewed By: craig.topper

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61010

llvm-svn: 359994
2019-05-05 18:59:22 +00:00
Philip Reames 37104d7189 [LPM/BPI] Preserve BPI through trivial loop pass pipeline (e.g. LCSSA, LoopSimplify)
Currently, we do not expose BPI to loop passes at all. In the old pass manager, we appear to have been ignoring the fact that LCSSA and/or LoopSimplify didn't preserve BPI, and making it available to the following loop passes anyways.  In the new one, it's invalidated before running any loop pass if either LCSSA or LoopSimplify actually make changes. If they don't make changes, then BPI is valid and available.  So, we go ahead and teach LCSSA and LoopSimplify how to preserve BPI for consistency between old and new pass managers.

This patch avoids an invalidation between the two requires in the following trivial pass pipeline:
opt -passes="requires<branch-prob>,loop(no-op-loop),requires<branch-prob>"
(when the input file is one which requires either LCSSA or LoopSimplify to canonicalize the loops)

Differential Revision: https://reviews.llvm.org/D60790

llvm-svn: 358901
2019-04-22 17:13:43 +00:00
Alina Sbirlea 97468e9282 [MemorySSA & LoopPassManager] Update MemorySSA in formDedicatedExitBlocks.
MemorySSA is now updated when forming dedicated exit blocks.
Resolves PR40037.

llvm-svn: 354623
2019-02-21 21:13:34 +00:00
Max Kazantsev 20b9189975 [NFC] Rename DontDeleteUselessPHIs --> KeepOneInputPHIs
llvm-svn: 353801
2019-02-12 07:09:29 +00:00
Craig Topper 784929d045 Implementation of asm-goto support in LLVM
This patch accompanies the RFC posted here:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/127239.html

This patch adds a new CallBr IR instruction to support asm-goto
inline assembly like gcc as used by the linux kernel. This
instruction is both a call instruction and a terminator
instruction with multiple successors. Only inline assembly
usage is supported today.

This also adds a new INLINEASM_BR opcode to SelectionDAG and
MachineIR to represent an INLINEASM block that is also
considered a terminator instruction.

There will likely be more bug fixes and optimizations to follow
this, but we felt it had reached a point where we would like to
switch to an incremental development model.

Patch by Craig Topper, Alexander Ivchenko, Mikhail Dvoretckii

Differential Revision: https://reviews.llvm.org/D53765

llvm-svn: 353563
2019-02-08 20:48:56 +00:00
Chandler Carruth 2946cd7010 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
2019-01-19 08:50:56 +00:00
Chandler Carruth edb12a838a [TI removal] Make variables declared as `TerminatorInst` and initialized
by `getTerminator()` calls instead be declared as `Instruction`.

This is the biggest remaining chunk of the usage of `getTerminator()`
that insists on the narrow type and so is an easy batch of updates.
Several files saw more extensive updates where this would cascade to
requiring API updates within the file to use `Instruction` instead of
`TerminatorInst`. All of these were trivial in nature (pervasively using
`Instruction` instead just worked).

llvm-svn: 344502
2018-10-15 10:04:59 +00:00
Alina Sbirlea ab6f84f763 Update MemorySSA in BasicBlockUtils.
Summary:
Extend BasicBlocksUtils to update MemorySSA.

Subscribers: sanjoy, arsenm, nhaehnle, jlebar, Prazek, llvm-commits

Differential Revision: https://reviews.llvm.org/D45300

llvm-svn: 340365
2018-08-21 23:32:03 +00:00
David Blaikie 31b98d2e99 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
2018-06-04 21:23:21 +00:00
Nicola Zaghen d34e60ca85 Rename DEBUG macro to LLVM_DEBUG.
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.

In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.

Differential Revision: https://reviews.llvm.org/D43624

llvm-svn: 332240
2018-05-14 12:53:11 +00:00
Adrian Prantl 5f8f34e459 Remove \brief commands from doxygen comments.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

  for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46290

llvm-svn: 331272
2018-05-01 15:54:18 +00:00
Florian Hahn 8fe04ad3f7 [LoopSimplify] Use BB::instructionsWithoutDebug to skip DbgInfo (NFC).
This patch updates some code responsible the skip debug info to use
BasicBlock::instructionsWithoutDebug. I think this makes things slightly
simpler and more direct.

Reviewers: aprantl, vsk, chandlerc

Reviewed By: aprantl

Differential Revision: https://reviews.llvm.org/D46253

llvm-svn: 331217
2018-04-30 19:19:36 +00:00
Max Kazantsev c54e67d6b9 [NFC] Remove recently added SE verification because it may be false-positive
llvm-svn: 330699
2018-04-24 09:11:01 +00:00
Max Kazantsev b1137c42fa [LoopSimplify] Fix incorrect SCEV invalidation
In the function `simplifyOneLoop` we optimistically assume that changes in the
inner loop only affect this very loop and have no impact on its parents. In fact,
after rL329047 has been merged, we can now calculate exit counts for outer
loops which may depend on inner loops. Thus, we need to invalidate all parents
when we do something to a loop.

There is an evidence of incorrect behavior of `simplifyOneLoop`: when we insert
`SE->verify()` check in the end of this funciton, it fails on a bunch of existing
test, in particular:

    LLVM :: Transforms/LoopUnroll/peel-loop-not-forced.ll
    LLVM :: Transforms/LoopUnroll/peel-loop-pgo.ll
    LLVM :: Transforms/LoopUnroll/peel-loop.ll
    LLVM :: Transforms/LoopUnroll/peel-loop2.ll

Note that previously we have fixed issues of this variety, see rL328483.
This patch makes this function invalidate the outermost loop properly.

Differential Revision: https://reviews.llvm.org/D45937
Reviewed By: chandlerc

llvm-svn: 330576
2018-04-23 10:32:37 +00:00
David Blaikie a373d18eb7 Transforms: Introduce Transforms/Utils.h rather than spreading the declarations amongst Scalar.h and IPO.h
Fixes layering - Transforms/Utils shouldn't depend on including a Scalar
or IPO header, because Scalar and IPO depend on Utils.

llvm-svn: 328717
2018-03-28 17:44:36 +00:00
David Blaikie 2be3922807 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
2018-03-21 22:34:23 +00:00
Sanjoy Das def1729dc4 Use a BumpPtrAllocator for Loop objects
Summary:
And now that we no longer have to explicitly free() the Loop instances, we can
(with more ease) use the destructor of LoopBase to do what LoopBase::clear() was
doing.

Reviewers: chandlerc

Subscribers: mehdi_amini, mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D38201

llvm-svn: 314375
2017-09-28 02:45:42 +00:00