Commit Graph

20619 Commits

Author SHA1 Message Date
Florian Hahn 3afb974aa5 [LoopInterchange] Preserve ScalarEvolution, by forgetting about interchanged loops.
As preparation for LoopInterchange becoming a loop pass, it needs to
preserve ScalarEvolution. Even though interchanging should not change
the trip count of the loop, it modifies loop entry, latch and exit
blocks.

I added -verify-scev to some loop interchange tests, but the verification does
not catch problems caused by missing invalidation of SE in loop interchange, as
the trip counts themselves do not change. So there might be potential to
make the SE verification covering more stuff in the future.

Reviewers: mkazantsev, efriedma, karthikthecool

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D52026

llvm-svn: 342209
2018-09-14 07:50:20 +00:00
Max Kazantsev e9765ac275 [NFC] Remove meaningless code from GVN
llvm-svn: 342202
2018-09-14 04:50:38 +00:00
Hideki Saito d19851ac7e Fix for the buildbot failure http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/23635
from the commit (r342197) of https://reviews.llvm.org/D50820.

llvm-svn: 342201
2018-09-14 02:02:57 +00:00
Hideki Saito ea7f3035a0 [VPlan] Implement initial vector code generation support for simple outer loops.
Summary:
[VPlan] Implement vector code generation support for simple outer loops.

Context: Patch Series #1 for outer loop vectorization support in LV  using VPlan. (RFC: http://lists.llvm.org/pipermail/llvm-dev/2017-December/119523.html).
                                                          
This patch introduces vector code generation support for simple outer loops that are currently supported in the VPlanNativePath. Changes here essentially do the following:

  - force vector code generation using explicit vectorize_width

  - add conservative early returns in cost model and other places for VPlanNativePath

  - add code for setting up outer loop inductions 

  - support for widening non-induction PHIs that can result from inner loops and uniform conditional branches

  - support for generating uniform inner branches

We plan to add a handful C outer loop executable tests once the initial code generation support is committed. This patch is expected to be NFC for the inner loop vectorizer path. Since we are moving in the direction of supporting outer loop vectorization in LV, it may also be time to rename classes such as InnerLoopVectorizer. 

Reviewers: fhahn, rengolin, hsaito, dcaballe, mkuper, hfinkel, Ayal

Reviewed By: fhahn, hsaito

Subscribers: dmgreen, bollu, tschuett, rkruppe, rogfer01, llvm-commits

Differential Revision: https://reviews.llvm.org/D50820

llvm-svn: 342197
2018-09-14 00:36:00 +00:00
Matt Morehouse 3bea25e554 [SanitizerCoverage] Create comdat for global arrays.
Summary:
Place global arrays in comdat sections with their associated functions.
This makes sure they are stripped along with the functions they
reference, even on the BFD linker.

Reviewers: eugenis

Reviewed By: eugenis

Subscribers: eraman, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D51902

llvm-svn: 342186
2018-09-13 21:45:55 +00:00
Roman Lebedev 6dc87004fa [InstCombine] Inefficient pattern for high-bits checking 2 (PR38708)
Summary:
It is sometimes important to check that some newly-computed value
is non-negative and only n bits wide (where n is a variable.)
There are many ways to check that:
https://godbolt.org/z/o4RB8D
The last variant seems best?
(I'm sure there are some other variations i haven't thought of..)

More complicated, canonical pattern:
https://rise4fun.com/Alive/uhA

We do need to have two `switch()`'es like this,
to not mismatch the swappable predicates.

https://bugs.llvm.org/show_bug.cgi?id=38708

Reviewers: spatel, craig.topper, RKSimon

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D52001

llvm-svn: 342173
2018-09-13 20:33:12 +00:00
George Burgess IV d565b0f017 [PartiallyInlineLibCalls] Add DebugCounter support
This adds DebugCounter support to the PartiallyInlineLibCalls pass,
which should make debugging/automated bisection easier in the future.

Patch by Zhizhou Yang!

Differential Revision: https://reviews.llvm.org/D50093

llvm-svn: 342172
2018-09-13 20:33:04 +00:00
George Burgess IV 7a8dc3dafa [DCE] Add DebugCounter support
Patch by Zhizhou Yang!

Differential Revision: https://reviews.llvm.org/D50092

llvm-svn: 342170
2018-09-13 20:29:50 +00:00
Craig Topper 8fc05ce340 [InstCombine] Fold (xor (min/max X, Y), -1) -> (max/min ~X, ~Y) when X and Y are freely invertible.
This allows the xor to be removed completely.

This might help with recomitting r341674, but seems good regardless.

Coincidentally fixes PR38915.

Differential Revision: https://reviews.llvm.org/D51964

llvm-svn: 342163
2018-09-13 18:52:58 +00:00
Sanjay Patel 37e464876b [InstCombine] remove checks for IsFreeToInvert()
I accidentally committed this diff with rL342147 because
I had applied D51964. We probably do need those checks,
but D51964 has tests and more discussion/motivation,
so they should be re-added with that patch.

llvm-svn: 342149
2018-09-13 16:18:12 +00:00
Sanjay Patel 6f00fc3317 [InstCombine] reorder folds to reduce chance of infinite loops
I don't have a test case for this, but it's motivated by
the discussion in D51964, and I've added TODO comments for
the better fix - move simplifications into instsimplify
because that's more efficient and reduces risk of infinite
loops in instcombine caused by transforms trying to do the
opposite folds.

In this case, we know that the transform that tries to move
'not' through min/max can be fooled by the multiple uses
of a value in another min/max, so try to squash the 
foldSPFofSPF() patterns first.

llvm-svn: 342147
2018-09-13 16:04:06 +00:00
Sanjay Patel d341988c86 revert r341288 - [Reassociate] swap binop operands to increase factoring potential
This causes or exposes indeterminism that is visible in the output of -reassociate.

llvm-svn: 342083
2018-09-12 21:29:11 +00:00
Roman Lebedev 75404fb9f8 [InstCombine] Inefficient pattern for high-bits checking (PR38708)
Summary:
It is sometimes important to check that some newly-computed value
is non-negative and only `n` bits wide (where `n` is a variable.)
There are **many** ways to check that:
https://godbolt.org/z/o4RB8D
The last variant seems best?
(I'm sure there are some other variations i haven't thought of..)

Let's handle the second variant first, since it is much simpler.
https://rise4fun.com/Alive/LYjY

https://bugs.llvm.org/show_bug.cgi?id=38708

Reviewers: spatel, craig.topper, RKSimon

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D51985

llvm-svn: 342067
2018-09-12 18:19:43 +00:00
Alexandros Lamprineas 54d56f274c [GVNHoist] computeInsertionPoints() miscalculates IDF
Fix for https://bugs.llvm.org/show_bug.cgi?id=38912.

In GVNHoist::computeInsertionPoints() we iterate over the Value
Numbers and calculate the Iterated Dominance Frontiers without
clearing the IDFBlocks vector first. IDFBlocks ends up accumulating
an insane number of basic blocks, which bloats the compilation time
of SemaChecking.cpp with ubsan enabled.

Differential Revision: https://reviews.llvm.org/D51980

llvm-svn: 342055
2018-09-12 14:28:23 +00:00
David Green 2352b30c96 [SimplifyCFG] Put an alignment on generated switch tables
Previously the alignment on the newly created switch table data was not set,
meaning that DataLayout::getPreferredAlignment was free to overalign it to 16
bytes. This causes unnecessary code bloat.

Differential Revision: https://reviews.llvm.org/D51800

llvm-svn: 342039
2018-09-12 09:54:17 +00:00
Florian Hahn 1086ce2397 [LV] Move InterleaveGroup and InterleavedAccessInfo to VectorUtils.h (NFC)
Move the 2 classes out of LoopVectorize.cpp to make it easier to re-use
them for VPlan outside LoopVectorize.cpp

Reviewers: Ayal, mssimpso, rengolin, dcaballe, mkuper, hsaito, hfinkel, xbolva00

Reviewed By: rengolin, xbolva00

Differential Revision: https://reviews.llvm.org/D49488

llvm-svn: 342027
2018-09-12 08:01:57 +00:00
Vikram TV 7e98d69847 Break LoopUtils into an Analysis file.
Summary:
The InductionDescriptor and RecurrenceDescriptor classes basically analyze the IR to identify the respective IVs. So, it is better to have them in the "Analysis" directory instead of the "Transforms" directory.

The rationale for this is to make the Induction and Recurrence descriptor classes available for analysis passes. Currently including them in an analysis pass produces link error (http://lists.llvm.org/pipermail/llvm-dev/2018-July/124456.html).

Induction and Recurrence descriptors are moved from Transforms/Utils/LoopUtils.h|cpp to Analysis/IVDescriptors.h|cpp.

Reviewers: dmgreen, llvm-commits, hfinkel

Reviewed By: dmgreen

Subscribers: mgorny

Differential Revision: https://reviews.llvm.org/D51153

llvm-svn: 342016
2018-09-12 01:59:43 +00:00
Sanjay Patel 1cf0734b2f [InstCombine] add folds for unsigned-overflow compares
Name: op_ugt_sum
  %a = add i8 %x, %y
  %r = icmp ugt i8 %x, %a
  =>
  %notx = xor i8 %x, -1
  %r = icmp ugt i8 %y, %notx

Name: sum_ult_op
  %a = add i8 %x, %y
  %r = icmp ult i8 %a, %x
  =>
  %notx = xor i8 %x, -1
  %r = icmp ugt i8 %y, %notx

https://rise4fun.com/Alive/ZRxI

AFAICT, this doesn't interfere with any add-saturation patterns
because those have >1 use for the 'add'. But this should be
better for IR analysis and codegen in the basic cases.

This is another fold inspired by PR14613:
https://bugs.llvm.org/show_bug.cgi?id=14613

llvm-svn: 342004
2018-09-11 22:40:20 +00:00
Alexandros Lamprineas fe0512d575 Revert "[GVNHoist] Re-enable GVNHoist by default"
This reverts rL341954.

The builder `sanitizer-x86_64-linux-bootstrap-ubsan` has been
failing with timeouts at stage2 clang/ubsan:

[3065/3073] Linking CXX executable bin/lld
command timed out: 1200 seconds without output running python
../sanitizer_buildbot/sanitizers/buildbot_selector.py,
attempting to kill

llvm-svn: 342001
2018-09-11 22:10:57 +00:00
Sanjay Patel 26725bdc50 [InstCombine] add folds for icmp with xor mask constant
These are the folds in Alive;
Name: xor_ult
Pre: isPowerOf2(-C1)
%xor = xor i8 %x, C1
%r = icmp ult i8 %xor, C1
=>
%r = icmp ugt i8 %x, ~C1

Name: xor_ugt
Pre: isPowerOf2(C1+1)
%xor = xor i8 %x, C1
%r = icmp ugt i8 %xor, C1
=>
%r = icmp ugt i8 %x, C1

https://rise4fun.com/Alive/Vty

The ugt case in its simplest form was already handled by DemandedBits,
but that's not ideal as shown in the multi-use test.

I'm not sure if these are all of the symmetrical folds, but I adjusted 
the existing code for one of the folds to try to show the similarities.

There's no obvious connection, but this is another preliminary step 
for PR14613...
https://bugs.llvm.org/show_bug.cgi?id=14613

llvm-svn: 341997
2018-09-11 22:00:15 +00:00
Matt Morehouse f0d7daa972 Revert "[SanitizerCoverage] Create comdat for global arrays."
This reverts r341987 since it will cause trouble when there's a module
ID collision.

llvm-svn: 341995
2018-09-11 21:15:41 +00:00
Matt Morehouse 7ce6032432 [SanitizerCoverage] Create comdat for global arrays.
Summary:
Place global arrays in comdat sections with their associated functions.
This makes sure they are stripped along with the functions they
reference, even on the BFD linker.

Reviewers: eugenis

Reviewed By: eugenis

Subscribers: eraman, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D51902

llvm-svn: 341987
2018-09-11 20:10:40 +00:00
Alina Sbirlea a496143c9e Update MemorySSA in LoopUnswitch.
Summary:
Update MemorySSA in old LoopUnswitch pass.
Actual dependency and update is disabled by default.

Subscribers: sanjoy, jlebar, Prazek, llvm-commits

Differential Revision: https://reviews.llvm.org/D45301

llvm-svn: 341984
2018-09-11 19:19:21 +00:00
Sanjay Patel 342c3bcf11 [InstCombine] enhance vector demanded elements to look at a vector select condition operand
I noticed that we were not back-propagating undef lanes to shuffle masks when we have a 
shuffle that reduces the vector width. This is part of investigating/solving PR38691:
https://bugs.llvm.org/show_bug.cgi?id=38691

The DAG equivalent was proposed with:
D51696

Differential Revision: https://reviews.llvm.org/D51433

llvm-svn: 341981
2018-09-11 18:49:00 +00:00
Vedant Kumar 727d89526e [gcov] Fix branch counters with switch statements (fix PR38821)
Right now, the counters are added in regards of the number of successors
for a given BasicBlock: it's good when we've only 1 or 2 successors (at
least with BranchInstr). But in the case of a switch statement, the
BasicBlock after switch has several predecessors and we need know from
which BB we're coming from.

So the idea is to revert what we're doing: add a PHINode in each block
which will select the counter according to the incoming BB.  They're
several pros for doing that:

- we fix the "switch" bug
- we remove the function call to "__llvm_gcov_indirect_counter_increment"
  and the lookup table stuff
- we replace by PHINodes, so the optimizer will probably makes a better
  job.

Patch by calixte!

Differential Revision: https://reviews.llvm.org/D51619

llvm-svn: 341977
2018-09-11 18:38:34 +00:00
Craig Topper 4e63db8387 [InstCombine] Fix incorrect usage of getPrimitiveSizeInBits when we should be using the element size for vectors
For vectors, getPrimitiveSizeInBits returns the full vector width. This code should using the element size for vectors. This could be fixed by calling getScalarSizeInBits, but its even easier to just get it from the APInt we're checking.

Differential Revision: https://reviews.llvm.org/D51938

llvm-svn: 341971
2018-09-11 17:57:20 +00:00
Florian Hahn 5b7e21a6b7 [CallSiteSplitting] Add debug location to created PHI nodes.
There are 2 cases when we create PHI nodes:
 * For the result of the call that was duplicated in the split blocks.
   Those PHI nodes should have the debug location of the call.

 * For values produced before the call. Those instructions need to be
   duplicated in the split blocks and the PHI nodes should have the
   debug locations of those instructions.

Fixes PR37962.

Reviewers: junbuml, gbedwell, vsk

Reviewed By: junbuml

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D51919

llvm-svn: 341970
2018-09-11 17:55:58 +00:00
Matt Morehouse 40fbdd0c4f Revert "[SanitizerCoverage] Create comdat for global arrays."
This reverts r341951 due to bot breakage.

llvm-svn: 341965
2018-09-11 17:20:14 +00:00
Craig Topper 12fd6bd4ad [InstCombine] Use dyn_cast instead of match(m_Constant). NFC
llvm-svn: 341962
2018-09-11 16:51:26 +00:00
Craig Topper a57bb61a3e [InstCombine] Support (mul (sext x), cst) --> (sext (mul x, cst')) and (mul (zext x), cst) --> (zext (mul x, cst')) for vectors constants.
Similar to D51236, but for mul instead of add.

Differential Revision: https://reviews.llvm.org/D51900

llvm-svn: 341961
2018-09-11 16:51:24 +00:00
Alexandros Lamprineas db18e972d7 [GVNHoist] Re-enable GVNHoist by default
Rebase rL340922 since https://bugs.llvm.org/show_bug.cgi?id=38807
has been fixed by rL341947.

llvm-svn: 341954
2018-09-11 15:55:45 +00:00
Matt Morehouse eac270caf4 [SanitizerCoverage] Create comdat for global arrays.
Summary:
Place global arrays in comdat sections with their associated functions.
This makes sure they are stripped along with the functions they
reference, even on the BFD linker.

Reviewers: eugenis

Reviewed By: eugenis

Subscribers: eraman, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D51902

llvm-svn: 341951
2018-09-11 15:23:14 +00:00
Johannes Doerfert ae3cfeb3ad [FuncAttrs] Remove "access range attributes" for read-none functions
The presence of readnone and an access range attribute (argmemonly,
inaccessiblememonly, inaccessiblemem_or_argmemonly) is considered an
error by the verifier. This seems strict but also not wrong. This
patch makes sure function attribute detection will remove all access
range attributes for readnone functions.

llvm-svn: 341927
2018-09-11 11:51:29 +00:00
Serguei Katkov 5f4a9e9ea0 [LICM] Avoid duplicate work during building AliasSetTracker
Currently we re-use cached info from sub loops or traverse them
to populate AliasSetTracker. But after that we traverse all basic blocks
from the current loop. This is redundant work.

All what we need is traversing the all basic blocks from the loop except
those which are used to get the data from the cache.

This should improve compile time only.

Reviewers: mkazantsev, reames, kariddi, anna
Reviewed By: reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D51715

llvm-svn: 341896
2018-09-11 04:07:36 +00:00
Max Kazantsev e6413919ce [IndVars][NFC] Refactor to make modifications of Changed transparent
IndVarSimplify's design is somewhat odd in the way how it reports that
some transform has made a change. It has a `Changed` field which can
be set from within any function, which makes it hard to track whether or
not it was set properly after a transform was made. It leads to oversights
in setting this flag where needed, see example in PR38855.

This patch removes the `Changed` field, turns it into a local and unifies
the signatures of all relevant transform functions to return boolean value
which designates whether or not this transform has made a change.

Differential Revision: https://reviews.llvm.org/D51850
Reviewed By: skatkov

llvm-svn: 341893
2018-09-11 03:57:22 +00:00
Philip Reames 1f52e38e8e [LICM] (re-)simplify code using MemoryLocation API [NFC]
I'd made exactly this same change before, but it appears to have been accidentally reverted in another change.  (I'm assuming accidental since it was without comment or test case, and in an unrelated change.)

llvm-svn: 341892
2018-09-11 03:28:28 +00:00
Alina Sbirlea 116caa2920 [InstCombine] Partially revert rL341674 due to PR38897.
Summary:
Revert min/max changes in rL341674 dues to high compile times causing timeouts (PR38897).
Checking in to unblock failing builds. Patch available for post-commit review and re-revert once resolved.
Working on a smaller reproducer for PR38897.

Reviewers: craig.topper, spatel

Subscribers: sanjoy, jlebar, llvm-commits

Differential Revision: https://reviews.llvm.org/D51897

llvm-svn: 341883
2018-09-10 23:47:21 +00:00
Sanjay Patel 691d1a40e2 [InstCombine] use SelectInst operand names to make code clearer; NFC
Cleanup step for D51433.

llvm-svn: 341850
2018-09-10 18:37:59 +00:00
Sebastian Pop a1f20fcc96 HotColdSplitting: check that target supports cold calling convention
Before tagging a function with coldcc make sure the target supports cold calling
convention. Without this patch HotColdSplitting pass fails on aarch64 with:

  fatal error: error in backend: Unsupported calling convention.

llvm-svn: 341838
2018-09-10 15:08:02 +00:00
Sebastian Pop 6284b54ccd add flag instead of using a constant [NFC]
llvm-svn: 341837
2018-09-10 15:07:59 +00:00
Sebastian Pop ea0a91298d make flag name more specific to gvn [NFC]
llvm-svn: 341836
2018-09-10 15:07:56 +00:00
Tim Northover 12c1f7675f InstCombine: move hasOneUse check to the top of foldICmpAddConstant
There were two combines not covered by the check before now, neither of which
actually differed from normal in the benefit analysis.

The most recent seems to be because it was just added at the top of the
function (naturally). The older is from way back in 2008 (r46687) when we just
didn't put those checks in so routinely, and has been diligently maintained
since.

llvm-svn: 341831
2018-09-10 14:26:44 +00:00
Benjamin Kramer 28559a2605 Don't create a temporary vector of loop blocks just to iterate over them.
Loop's getBlocks returns an ArrayRef.

llvm-svn: 341821
2018-09-10 12:32:06 +00:00
John Brawn 8967e18c4a [GVN] Invalidate cached info for values replaced by equality propagation
When GVN propagates an equality by replacing one value with another it also
needs to invalidate the cached information for the value being replaced.

Differential Revision: https://reviews.llvm.org/D51218

llvm-svn: 341820
2018-09-10 12:23:05 +00:00
Max Kazantsev fde88578e5 [IndVars] Set Changed if rewriteFirstIterationLoopExitValues changes IR. PR38863
Currently, `rewriteFirstIterationLoopExitValues` does not set Changed flag even if it makes
changes in the IR. There is no clear evidence that it can cause a crash, but it
looks highly suspicious and likely invalid.

Differential Revision: https://reviews.llvm.org/D51779
Reviewed By: skatkov

llvm-svn: 341779
2018-09-10 06:50:16 +00:00
Max Kazantsev 4d10ba37b9 [IndVars] Set Changed if sinkUnusedInvariants changes IR. PR38863
Currently, `sinkUnusedInvariants` does not set Changed flag even if it makes
changes in the IR. There is no clear evidence that it can cause a crash, but it
looks highly suspicious and likely invalid.

Differential Revision: https://reviews.llvm.org/D51777
Reviewed By: skatkov

llvm-svn: 341777
2018-09-10 06:32:00 +00:00
Vikram TV 09be521d4d Move a transformation routine from LoopUtils to LoopVectorize.
Summary:
Move InductionDescriptor::transform() routine from LoopUtils to its only uses in LoopVectorize.cpp.
Specifically, the function is renamed as InnerLoopVectorizer::emitTransformedIndex().

This is a child to D51153.

Reviewers: dmgreen, llvm-commits

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D51837

llvm-svn: 341776
2018-09-10 06:16:44 +00:00
Vikram TV 6594dc377d Move createMinMaxOp() out of RecurrenceDescriptor.
Reviewers: dmgreen, llvm-commits

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D51838

llvm-svn: 341773
2018-09-10 05:05:08 +00:00
Abderrazek Zaafrani c30dfb2dfc [SimplifyIndVar] Avoid generating truncate instructions with non-hoisted Laod operand.
Differential Revision: https://reviews.llvm.org/D49151

llvm-svn: 341726
2018-09-07 22:41:57 +00:00
Alina Sbirlea f98c2c5e6d [MemorySSA] Update MemoryPhi wiring for block splitting to consider if identical edges were merged.
Summary:
Block splitting is done with either identical edges being merged, or not.
Only critical edges can be split without merging identical edges based on an option.
Teach the memoryssa updater to take this into account: for the same edge between two blocks only move one entry from the Phi in Old to the new Phi in New.

Reviewers: george.burgess.iv

Subscribers: sanjoy, jlebar, Prazek, llvm-commits

Differential Revision: https://reviews.llvm.org/D51563

llvm-svn: 341709
2018-09-07 21:14:48 +00:00