Commit Graph

18959 Commits

Author SHA1 Message Date
Sanjay Patel 0f9b4773c1 [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
2017-09-27 14:54:16 +00:00
Hongbin Zheng d1b7b2efba [SimplifyIndVar] Constant fold IV users
This patch tries to transform cases like:

for (unsigned i = 0; i < N; i += 2) {
  bool c0 = (i & 0x1) == 0;
  bool c1 = ((i + 1) & 0x1) == 1;
}
To

for (unsigned i = 0; i < N; i += 2) {
  bool c0 = true;
  bool c1 = true;
}

This commit also update test/Transforms/IndVarSimplify/replace-srem-by-urem.ll to prevent constant folding.

Differential Revision: https://reviews.llvm.org/D38272

llvm-svn: 314266
2017-09-27 03:11:46 +00:00
Sanjoy Das eda7a86d42 [BypassSlowDivision] Improve our handling of divisions by constants
Summary:
Don't bail out on constant divisors for divisions that can be narrowed without
introducing control flow .  This gives us a 32 bit multiply instead of an
emulated 64 bit multiply in the generated PTX assembly.

Reviewers: jlebar

Subscribers: jholewinski, mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D38265

llvm-svn: 314253
2017-09-26 21:54:27 +00:00
Craig Topper 8bf622174d [InstCombine] Remove one use restriction on the shift for calls to foldICmpAndShift.
If this transformation succeeds, we're going to remove our dependency on the shift by rewriting the and. So it doesn't matter how many uses the shift has.

This distributes the one use check to other transforms in foldICmpAndConstConst that do need it.

Differential Revision: https://reviews.llvm.org/D38206

llvm-svn: 314233
2017-09-26 18:47:25 +00:00
Sanjay Patel 1d04b5bacf [DSE] Merge stores when the later store only writes to memory locations the early store also wrote to (2nd try)
This is a 2nd attempt at:
https://reviews.llvm.org/rL310055
...which was reverted at rL310123 because of PR34074:
https://bugs.llvm.org/show_bug.cgi?id=34074

In this version, we break out of the inner loop after we successfully merge and kill a pair of stores. In the
earlier rev, we were continuing instead, which meant we could process the invalid info from a now dead store.

Original commit message (authored by Filipe Cabecinhas):

This fixes PR31777.

If both stores' values are ConstantInt, we merge the two stores
(shifting the smaller store appropriately) and replace the earlier (and
larger) store with an updated constant.

In the future we should also support vectors of integers. And maybe
float/double if we can.  

Differential Revision: https://reviews.llvm.org/D30703

llvm-svn: 314206
2017-09-26 13:54:28 +00:00
Sylvestre Ledru e7d4cd639b Don't move llvm.localescape outside the entry block in the GCOV profiling pass
Summary:
This fixes https://bugs.llvm.org/show_bug.cgi?id=34714.

Patch by Marco Castelluccio

Reviewers: rnk

Reviewed By: rnk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D38224

llvm-svn: 314201
2017-09-26 11:56:43 +00:00
Matthias Braun cc603ee3d5 TargetLibraryInfo: Stop guessing wchar_t size
Usually the frontend communicates the size of wchar_t via metadata and
we can optimize wcslen (and possibly other calls in the future). In
cases without the wchar_size metadata we would previously try to guess
the correct size based on the target triple; however this is fragile to
keep up to date and may miss users manually changing the size via flags.
Better be safe and stop guessing and optimizing if the frontend didn't
communicate the size.

Differential Revision: https://reviews.llvm.org/D38106

llvm-svn: 314185
2017-09-26 02:36:57 +00:00
Vlad Tsyrklevich 998b220e97 Add section headers to SpecialCaseLists
Summary:
Sanitizer blacklist entries currently apply to all sanitizers--there
is no way to specify that an entry should only apply to a specific
sanitizer. This is important for Control Flow Integrity since there are
several different CFI modes that can be enabled at once. For maximum
security, CFI blacklist entries should be scoped to only the specific
CFI mode(s) that entry applies to.

Adding section headers to SpecialCaseLists allows users to specify more
information about list entries, like sanitizer names or other metadata,
like so:

  [section1]
  fun:*fun1*
  [section2|section3]
  fun:*fun23*

The section headers are regular expressions. For backwards compatbility,
blacklist entries entered before a section header are put into the '[*]'
section so that blacklists without sections retain the same behavior.

SpecialCaseList has been modified to also accept a section name when
matching against the blacklist. It has also been modified so the
follow-up change to clang can define a derived class that allows
matching sections by SectionMask instead of by string.

Reviewers: pcc, kcc, eugenis, vsk

Reviewed By: eugenis, vsk

Subscribers: vitalybuka, llvm-commits

Differential Revision: https://reviews.llvm.org/D37924

llvm-svn: 314170
2017-09-25 22:11:11 +00:00
Craig Topper 30dc9797e9 [InstCombine] Move an optimization from foldICmpAndConstConst to foldICmpUsingKnownBits
All this optimization cares about is knowing how many low bits of LHS is known to be zero and whether that means that the result is 0 or greater than the RHS constant. It doesn't matter where the zeros in the low bits came from. So we don't need to specifically look for an AND. Instead we can use known bits.

Differential Revision: https://reviews.llvm.org/D38195

llvm-svn: 314153
2017-09-25 21:15:00 +00:00
Sanjay Patel ecb175608f [InstCombine] remove extract-of-select vector transform (2nd try)
The 1st attempt at this:
https://reviews.llvm.org/rL314117
was reverted at:
https://reviews.llvm.org/rL314118

because of bot fails for clang tests that were checking optimized IR. That should be fixed with:
https://reviews.llvm.org/rL314144
...so try again. 

Original commit message:

The transform to convert an extract-of-a-select-of-vectors was added at:
https://reviews.llvm.org/rL194013

And a question about the validity of this transform was raised in the review:
https://reviews.llvm.org/D1539:
...but not answered AFAICT>

Most of the motivating cases in that patch are now handled by other combines. These are the tests that were added with
the original commit, but they are not regressing even after we remove the transform in this patch.

The diffs we see after removing this transform cause us to avoid increasing the instruction count, so we don't want to do
those transforms as canonicalizations.

The motivation for not turning a vector-select-of-vectors into a scalar operation is shown in PR33301:
https://bugs.llvm.org/show_bug.cgi?id=33301
...in those cases, we'll get vector ops with this patch rather than the vector/scalar mix that we currently see.

Differential Revision: https://reviews.llvm.org/D38006

llvm-svn: 314147
2017-09-25 20:30:53 +00:00
Hongbin Zheng bbe448abd8 [SimplifyIndvar] Minor change to refine r314125, NFC
llvm-svn: 314130
2017-09-25 18:10:36 +00:00
Hongbin Zheng f0093e45c4 [SimplifyIndvar] Replace the srem used by IV if we can prove both of its operands are non-negative
Since now SCEV can handle 'urem', an 'urem' is a better canonical form than an 'srem' because it has well-defined behavior

This is a follow up of D34598

Differential Revision: https://reviews.llvm.org/D38072

llvm-svn: 314125
2017-09-25 17:39:40 +00:00
Sanjay Patel aa7f750bec revert r314117 because there are bogus clang tests that depend on the optimizer
llvm-svn: 314118
2017-09-25 17:00:04 +00:00
Sanjay Patel 9639897d77 [InstCombine] remove extract-of-select vector transform
The transform to convert an extract-of-a-select-of-vectors was added at:
rL194013

And a question about the validity of this transform was raised in the review:
https://reviews.llvm.org/D1539:
...but not answered AFAICT>

Most of the motivating cases in that patch are now handled by other combines. These are the tests that were added with
the original commit, but they are not regressing even after we remove the transform in this patch.

The diffs we see after removing this transform cause us to avoid increasing the instruction count, so we don't want to do
those transforms as canonicalizations.

The motivation for not turning a vector-select-of-vectors into a scalar operation is shown in PR33301:
https://bugs.llvm.org/show_bug.cgi?id=33301
...in those cases, we'll get vector ops with this patch rather than the vector/scalar mix that we currently see.

Differential Revision: https://reviews.llvm.org/D38006

llvm-svn: 314117
2017-09-25 16:41:34 +00:00
Alexey Bataev ccce7afee8 [SLP] Support for horizontal min/max reduction.
Summary:
SLP vectorizer supports horizontal reductions for Add/FAdd binary operations. Patch adds support for horizontal min/max reductions.
Function getReductionCost() is split to getArithmeticReductionCost() for binary operation reductions and getMinMaxReductionCost() for min/max reductions.
Patch fixes PR26956.

Reviewers: spatel, mkuper, hfinkel, RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D27846

llvm-svn: 314101
2017-09-25 13:34:59 +00:00
Craig Topper ea927baee2 [InstCombine] Teach foldICmpUsingKnownBits to simplify SLE/SGE/ULE/UGE to equality comparisons when the min/max ranges intersect in a single value.
This is the inverse of what we do for SGT/SLT/UGT/ULT.

llvm-svn: 314032
2017-09-22 21:47:22 +00:00
Craig Topper 3f364aa908 [InstCombine] Add constant splat handling to one of the ICMP_SLT/SGT cases in foldICmpUsingKnownBits.
llvm-svn: 314025
2017-09-22 19:54:15 +00:00
Craig Topper 3edda87c42 [InstCombine] Move the call to isSignBitCheck into getDemandedBitsLHSMask instead of calling it outside and passing its result through a flag. NFCI
The result of the isSignBitCheck isn't used anywhere else and this allows us to share the m_APInt call in the likely case that it isn't a sign bit check.

llvm-svn: 314018
2017-09-22 18:57:23 +00:00
Craig Topper 5b35b68785 [InstCombine] Simplify check for RHS being a splat constant in foldICmpUsingKnownBits by just checking Op1Min==Op1Max rather than going through m_APInt.
llvm-svn: 314017
2017-09-22 18:57:22 +00:00
Craig Topper 2c9b7d7894 [InstCombine] Make cases for ICMP_UGT/ICMP_ULT use similar formatting since they use similar code. NFC
llvm-svn: 314016
2017-09-22 18:57:20 +00:00
Artur Pilipenko 889dc1e3a5 Rework loop predication pass
We've found a serious issue with the current implementation of loop predication.
The current implementation relies on SCEV and this turned out to be problematic.
To fix the problem we had to rework the pass substantially. We have had the
reworked implementation in our downstream tree for a while. This is the initial
patch of the series of changes to upstream the new implementation.

For now the transformation is limited to the following case:
  * The loop has a single latch with either ult or slt icmp condition.
  * The step of the IV used in the latch condition is 1.
  * The IV of the latch condition is the same as the post increment IV of the guard condition.
  * The guard condition is ult.

See the review or the LoopPredication.cpp header for the details about the
problem and the new implementation.

Reviewed By: sanjoy, mkazantsev

Differential Revision: https://reviews.llvm.org/D37569

llvm-svn: 313981
2017-09-22 13:13:57 +00:00
Sanjoy Das 388b012f4e Rename markAsErased to erase, as pointed out in a previous review; NFC
llvm-svn: 313951
2017-09-22 01:47:41 +00:00
Reid Kleckner 0fe506bc5e Re-land r313825: "[IR] Add llvm.dbg.addr, a control-dependent version of llvm.dbg.declare"
The fix is to avoid invalidating our insertion point in
replaceDbgDeclare:
     Builder.insertDeclare(NewAddress, DIVar, DIExpr, Loc, InsertBefore);
+    if (DII == InsertBefore)
+      InsertBefore = &*std::next(InsertBefore->getIterator());
     DII->eraseFromParent();

I had to write a unit tests for this instead of a lit test because the
use list order matters in order to trigger the bug.

The reduced C test case for this was:
  void useit(int*);
  static inline void inlineme() {
    int x[2];
    useit(x);
  }
  void f() {
    inlineme();
    inlineme();
  }

llvm-svn: 313905
2017-09-21 19:52:03 +00:00
Daniel Jasper 7d2f38d600 Revert r313825: "[IR] Add llvm.dbg.addr, a control-dependent version of llvm.dbg.declare"
.. as well as the two subsequent changes r313826 and r313875.

This leads to segfaults in combination with ASAN. Will forward repro
instructions to the original author (rnk).

llvm-svn: 313876
2017-09-21 12:07:33 +00:00
Mikael Holmen 582e141007 [SROA] Really remove associated dbg.declare when removing dead alloca
Summary:
There already was code that tried to remove the dbg.declare, but that code
was placed after we had called
 I->replaceAllUsesWith(UndefValue::get(I->getType()));
on the alloca, so when we searched for the relevant dbg.declare, we
couldn't find it.

Now we do the search before we call RAUW so there is a chance to find it.

An existing testcase needed update due to this. Two dbg.declare with undef
were removed and then suddenly one of the two CHECKS failed.

Before this patch we got

  call void @llvm.dbg.declare(metadata i24* undef, metadata !14, metadata !DIExpression(DW_OP_LLVM_fragment, 32, 24)), !dbg !15
  call void @llvm.dbg.declare(metadata %struct.prog_src_register* undef, metadata !14, metadata !DIExpression()), !dbg !15
  call void @llvm.dbg.value(metadata i32 0, metadata !14, metadata !DIExpression(DW_OP_LLVM_fragment, 0, 32)), !dbg !15
  call void @llvm.dbg.value(metadata i32 0, metadata !14, metadata !DIExpression(DW_OP_LLVM_fragment, 32, 24)), !dbg !15

and with it we get

  call void @llvm.dbg.value(metadata i32 0, metadata !14, metadata !DIExpression(DW_OP_LLVM_fragment, 0, 32)), !dbg !15
  call void @llvm.dbg.value(metadata i32 0, metadata !14, metadata !DIExpression(DW_OP_LLVM_fragment, 32, 24)), !dbg !15

However, the CHECKs in the testcase checked things in a silly order, so
they only passed since they found things in the first dbg.declare. Now
we changed the order of the checks and the test passes.

Reviewers: rnk

Reviewed By: rnk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D37900

llvm-svn: 313875
2017-09-21 11:14:27 +00:00
Strahinja Petrovic 29202f6dc1 Fixed reverted commit rL312318
This patch contains fix for reverted commit
rL312318 which was causing failure due to use
of unchecked dyn_cast to CIInit.

Patch by: Nikola Prica.

llvm-svn: 313870
2017-09-21 10:04:02 +00:00
Serguei Katkov 675e304ef8 Revert "Re-enable "[IRCE] Identify loops with latch comparison against current IV value""
Revert the patch causing the functional failures.
The patch owner is notified with test cases which fail.
Test case has been provided to Maxim offline.

llvm-svn: 313857
2017-09-21 04:50:41 +00:00
Craig Topper 18887bf179 [InstCombine] Teach getDemandedBitsLHSMask to handle constant splat vectors
This replaces a ConstantInt dyn_cast with m_APInt

Differential Revision: https://reviews.llvm.org/D38100

llvm-svn: 313840
2017-09-20 23:48:58 +00:00
Matt Morehouse 4881a23ca8 [MSan] Disable sanitization for __sanitizer_dtor_callback.
Summary:
Eliminate unnecessary instrumentation at __sanitizer_dtor_callback
call sites.  Fixes https://github.com/google/sanitizers/issues/861.

Reviewers: eugenis, kcc

Reviewed By: eugenis

Subscribers: vitalybuka, llvm-commits, cfe-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D38063

llvm-svn: 313831
2017-09-20 22:53:08 +00:00
Sanjay Patel 73811a152a [SimplifyCFG] don't create a no-op subtract
I noticed this inefficiency while investigating PR34603:
https://bugs.llvm.org/show_bug.cgi?id=34603

This fix will likely push another bug (we don't maintain state of 'LateSimplifyCFG') 
into hiding, but I'll try to clean that up with a follow-up patch anyway.

llvm-svn: 313829
2017-09-20 22:31:35 +00:00
Reid Kleckner 3f547e87b2 [IR] Add llvm.dbg.addr, a control-dependent version of llvm.dbg.declare
Summary:
This implements the design discussed on llvm-dev for better tracking of
variables that live in memory through optimizations:
  http://lists.llvm.org/pipermail/llvm-dev/2017-September/117222.html

This is tracked as PR34136

llvm.dbg.addr is intended to be produced and used in almost precisely
the same way as llvm.dbg.declare is today, with the exception that it is
control-dependent. That means that dbg.addr should always have a
position in the instruction stream, and it will allow passes that
optimize memory operations on local variables to insert llvm.dbg.value
calls to reflect deleted stores. See SourceLevelDebugging.rst for more
details.

The main drawback to generating DBG_VALUE machine instrs is that they
usually cause LLVM to emit a location list for DW_AT_location. The next
step will be to teach DwarfDebug.cpp how to recognize more DBG_VALUE
ranges as not needing a location list, and possibly start setting
DW_AT_start_offset for variables whose lifetimes begin mid-scope.

Reviewers: aprantl, dblaikie, probinson

Subscribers: eraman, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D37768

llvm-svn: 313825
2017-09-20 21:52:33 +00:00
Craig Topper 562bf99ee6 [InstCombine] Handle (X & C2) < C1 --> (X & C2) == 0
We already did (X & C2) > C1 --> (X & C2) != 0, if any bit set in (X & C2) will produce a result greater than C1. But there is an equivalent inverse condition with <= C1 (which will be canonicalized to < C1+1)

Differential Revision: https://reviews.llvm.org/D38065

llvm-svn: 313819
2017-09-20 21:18:17 +00:00
Craig Topper a0c897f634 [InstCombine] Use APInt::getActiveBits() to avoid creating an APInt from a trailing zero count to do a comparison. NFCI
llvm-svn: 313792
2017-09-20 18:49:29 +00:00
Hans Wennborg 57c3341ada Revert r313771 "[SLP] Vectorize jumbled memory loads."
This broke the buildbots, e.g.
http://bb.pgr.jp/builders/test-llvm-i686-linux-RA/builds/391

> Summary:
> This patch tries to vectorize loads of consecutive memory accesses, accessed
> in non-consecutive or jumbled way. An earlier attempt was made with patch D26905
> which was reverted back due to some basic issue with representing the 'use mask'
> jumbled accesses.
>
> This patch fixes the mask representation by recording the 'use mask' in the usertree entry.
>
> Change-Id: I9fe7f5045f065d84c126fa307ef6ebe0787296df
>
> Subscribers: mzolotukhin
>
> Reviewed By: ayal
>
> Differential Revision: https://reviews.llvm.org/D36130
>
> Review comments updated accordingly
>
> Change-Id: I22ab0a8a9bac9d49d74baa81a08e1e486f5e75f0
>
> Added a TODO for sortLoadAccesses API
>
> Change-Id: I3c679bf1865422d1b45e17ea28f1992bca660b58
>
> Modified the TODO for sortLoadAccesses API
>
> Change-Id: Ie64a66cb5f9e2a7610438abb0e750c6e090f9565
>
> Review comment update for using OpdNum to insert the mask in respective location
>
> Change-Id: I016d0c1b29874e979efc0205bbf078991f92edce
>
> Fixes '-Wsign-compare warning' in LoopAccessAnalysis.cpp and code rebase
>
> Change-Id: I64b2ea5e68c1d7b6a028f5ef8251c5a97333f89b

llvm-svn: 313781
2017-09-20 18:00:03 +00:00
Quentin Colombet aa103b3d86 [InstCombine] Add select simplifications
In these cases, two selects have constant selectable operands for
both the true and false components and have the same conditional
expression.
We then create two arithmetic operations of the same type and feed a
final select operation using the result of the true arithmetic for the true
operand and the result of the false arithmetic for the false operand and reuse
the original conditionl expression.
The arithmetic operations are naturally folded as a consequence, leaving
only the newly formed select to replace the old arithmetic operation.

Patch by: Michael Berg <michael_c_berg@apple.com>
Differential Revision: https://reviews.llvm.org/D37019

llvm-svn: 313774
2017-09-20 17:32:16 +00:00
Mohammad Shahid 2b281de576 [SLP] Vectorize jumbled memory loads.
Summary:
This patch tries to vectorize loads of consecutive memory accesses, accessed
in non-consecutive or jumbled way. An earlier attempt was made with patch D26905
which was reverted back due to some basic issue with representing the 'use mask'
jumbled accesses.

This patch fixes the mask representation by recording the 'use mask' in the usertree entry.

Change-Id: I9fe7f5045f065d84c126fa307ef6ebe0787296df

Subscribers: mzolotukhin

Reviewed By: ayal

Differential Revision: https://reviews.llvm.org/D36130

Review comments updated accordingly

Change-Id: I22ab0a8a9bac9d49d74baa81a08e1e486f5e75f0

Added a TODO for sortLoadAccesses API

Change-Id: I3c679bf1865422d1b45e17ea28f1992bca660b58

Modified the TODO for sortLoadAccesses API

Change-Id: Ie64a66cb5f9e2a7610438abb0e750c6e090f9565

Review comment update for using OpdNum to insert the mask in respective location

Change-Id: I016d0c1b29874e979efc0205bbf078991f92edce

Fixes '-Wsign-compare warning' in LoopAccessAnalysis.cpp and code rebase

Change-Id: I64b2ea5e68c1d7b6a028f5ef8251c5a97333f89b
llvm-svn: 313771
2017-09-20 17:19:57 +00:00
Teresa Johnson f625118ec7 [ThinLTO] Fix dead stripping analysis for SamplePGO
Summary:
The fix for dead stripping analysis in the case of SamplePGO indirect
calls to local functions (r313151) introduced the possibility of an
infinite loop.

Make sure we check for the value being already live after we update it
for SamplePGO indirect call handling.

Reviewers: danielcdh

Subscribers: mehdi_amini, inglorion, llvm-commits, eraman

Differential Revision: https://reviews.llvm.org/D38086

llvm-svn: 313766
2017-09-20 17:09:47 +00:00
Alexander Kornienko 6a140234ed Revert r313736: "[SLP] Vectorize jumbled memory loads."
The revision breaks buildbots:
http://lab.llvm.org:8011/builders/clang-x86_64-debian-fast/builds/6694/steps/test/logs/stdio

llvm-svn: 313758
2017-09-20 14:53:07 +00:00
Mohammad Shahid f8db9bd857 [SLP] Vectorize jumbled memory loads.
Summary:
This patch tries to vectorize loads of consecutive memory accesses, accessed
in non-consecutive or jumbled way. An earlier attempt was made with patch D26905
which was reverted back due to some basic issue with representing the 'use mask' of
jumbled accesses.

This patch fixes the mask representation by recording the 'use mask' in the usertree entry.

Change-Id: I9fe7f5045f065d84c126fa307ef6ebe0787296df

Reviewers: mkuper, loladiro, Ayal, zvi, danielcdh

Reviewed By: Ayal

Subscribers: mzolotukhin

Differential Revision: https://reviews.llvm.org/D36130

Commit after rebase for patch D36130

Change-Id: I8add1c265455669ef288d880f870a9522c8c08ab
llvm-svn: 313736
2017-09-20 08:18:28 +00:00
Sanjoy Das 09613b122e Tighten the invariants around LoopBase::invalidate
Summary:
With this change:
 - Methods in LoopBase trip an assert if the receiver has been invalidated
 - LoopBase::clear frees up the memory held the LoopBase instance

This change also shuffles things around as necessary to work with this stricter invariant.

Reviewers: chandlerc

Subscribers: mehdi_amini, mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D38055

llvm-svn: 313708
2017-09-20 02:31:57 +00:00
Daniel Berlin 064cb68d18 GVNSink: Make ModelledPHIs constructor linear (and avoid edge case it worries about) by avoiding getIncomingValueForBlock
llvm-svn: 313702
2017-09-20 00:07:27 +00:00
Daniel Berlin dd323297d0 Revert "[GVNSink] Remove dependency on SmallPtrSet iteration order."
This reverts commit r312156, because now the op and block arrays are not in the same order :(.

llvm-svn: 313701
2017-09-20 00:07:25 +00:00
Daniel Berlin 9632dd7376 NewGVN: Remove unused includes
llvm-svn: 313700
2017-09-20 00:07:12 +00:00
Sanjoy Das 76ab23234c [LoopInfo] Make LoopBase and Loop destructors non-public
Summary:
See comment for why I think this is a good idea.

This change also:

 - Removes an SCEV test case.  The SCEV test was not testing anything useful (most of it was `#if 0` ed out) and it would need to be updated to deal with a private ~Loop::Loop.
 - Updates the loop pass manager test case to deal with a private ~Loop::Loop.
 - Renames markAsRemoved to markAsErased to contrast with removeLoop, via the usual remove vs. erase idiom we already have for instructions and basic blocks.

Reviewers: chandlerc

Subscribers: mehdi_amini, mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D37996

llvm-svn: 313695
2017-09-19 23:19:00 +00:00
Adam Nemet 15fccf0009 Allow ORE.emit to take a closure to delay building the remark object
In the lambda we are now returning the remark by value so we need to preserve
its type in the insertion operator.  This requires making the insertion
operator generic.

I've also converted a few cases to use the new API.  It seems to work pretty
well.  See the LoopUnroller for a slightly more interesting case.

llvm-svn: 313691
2017-09-19 23:00:55 +00:00
Dehao Chen 62b9c33e1e Import all inlined indirect call targets for SamplePGO.
Summary: In the ThinLTO compilation, if a function is inlined in the profiling binary, we need to inline it before annotation. If the callee is not available in the primary module, a first step is needed to import that callee function. For the current implementation, if the call is an indirect call, which has been promoted to >1 targets and inlined, SamplePGO will only import one target with the largest sample count. This patch fixed the bug to import all targets instead.

Reviewers: tejohnson, davidxl

Reviewed By: tejohnson

Subscribers: sanjoy, llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D36637

llvm-svn: 313678
2017-09-19 21:18:14 +00:00
Sanjay Patel ca14697c2b [SimplifyCFG] fix typos/formatting; NFC
llvm-svn: 313671
2017-09-19 20:58:14 +00:00
Dehao Chen b6e60c8b80 Handle profile mismatch correctly for SamplePGO.
Summary: Fix the bug when promoted call return type mismatches with the promoted function, we should not try to inline it. Otherwise it may lead to compiler crash.

Reviewers: davidxl, tejohnson, eraman

Reviewed By: tejohnson

Subscribers: llvm-commits, sanjoy

Differential Revision: https://reviews.llvm.org/D38018

llvm-svn: 313658
2017-09-19 18:26:54 +00:00
Reid Kleckner 1aa4ea8104 [gcov] Emit errors when opening the notes file fails
No time to write a test case, on to the next bug. =P

Discovered while investigating PR34659

llvm-svn: 313571
2017-09-18 21:31:48 +00:00
Sanjay Patel 55de1ed8e6 [SLP] clean up for vector store case; NFCI
llvm-svn: 313541
2017-09-18 16:20:15 +00:00
Craig Topper f264fcc704 [X86] Remove VPERM2F128/VPERM2I128 intrinsics and autoupgrade to native shuffles.
I've moved the test cases from the InstCombine optimizations to the backend to keep the coverage we had there. It covered every possible immediate so I've preserved the resulting shuffle mask for each of those immediates.

llvm-svn: 313450
2017-09-16 07:36:14 +00:00
Chandler Carruth beb22b5437 [SLP] Revert r312791 and other necessary commits, except for TTI and
CostModel.

The original patch added support for horizontal min/max reductions to
the SLP vectorizer.

This patch causes LLVM to miscompile fairly simple signed min
reductions. I have attached a test progrom to http://llvm.org/PR34635
that shows the behavior change after this patch. We found this in a test
for the open source Eigen library, but also in other code.

Unfortunately, the revert is moderately challenging. It required
reverting:
r313042: [SLP] Test with multiple uses of conditional op and wrong parent.
r312853: [SLP] Fix buildbots, NFC.
r312793: [SLP] Fix the warning about paths not returning the value, NFC.
r312791: [SLP] Support for horizontal min/max reduction.

And even then, I had to completely skip reverting the changes to TTI and
CostModel because r312832 rewrote so much of this code. Plus, the cost
modeling changes aren implicated in the miscompile, so they should be
fine and will just not be used until this gets re-introduced.

llvm-svn: 313409
2017-09-15 22:23:27 +00:00
Vivek Pandya b5ab895e2a This patch fixes https://bugs.llvm.org/show_bug.cgi?id=32352
It enables OptimizationRemarkEmitter::allowExtraAnalysis and MachineOptimizationRemarkEmitter::allowExtraAnalysis to return true not only for -fsave-optimization-record but when specific remarks are requested with
command line options.
The diagnostic handler used to be callback now this patch adds a class
DiagnosticHandler. It has virtual method to provide custom diagnostic handler
and methods to control which particular remarks are enabled. 
However LLVM-C API users can still provide callback function for diagnostic handler.

llvm-svn: 313390
2017-09-15 20:10:09 +00:00
Vivek Pandya df8598dcc4 This reverts r313381
llvm-svn: 313387
2017-09-15 19:53:54 +00:00
Vivek Pandya 00d887447b This patch fixes https://bugs.llvm.org/show_bug.cgi?id=32352
It enables OptimizationRemarkEmitter::allowExtraAnalysis and MachineOptimizationRemarkEmitter::allowExtraAnalysis to return true not only for -fsave-optimization-record but when specific remarks are requested with
command line options.
The diagnostic handler used to be callback now this patch adds a class
DiagnosticHandler. It has virtual method to provide custom diagnostic handler
and methods to control which particular remarks are enabled. 
However LLVM-C API users can still provide callback function for diagnostic handler.

llvm-svn: 313382
2017-09-15 19:30:59 +00:00
Anna Thomas f34537dff8 [RuntimeUnroll] Add heuristic for unrolling multi-exit loop
Add a profitability heuristic to enable runtime unrolling of multi-exit
loop: There can be atmost two unique exit blocks for the loop and the
second exit block should be a deoptimizing block. Also, there can be one
other exiting block other than the latch exiting block. The reason for
the latter is so that we limit the number of branches in the unrolled
code to being at most the unroll factor.  Deoptimizing blocks are rarely
taken so these additional number of branches created due to the
unrolling are predictable, since one of their target is the deopt block.

Reviewers: apilipenko, reames, evstupac, mkuper

Subscribers: llvm-commits

Reviewed by: reames

Differential Revision: https://reviews.llvm.org/D35380

llvm-svn: 313363
2017-09-15 15:56:05 +00:00
Anna Thomas 512dde77ba [RuntimeUnrolling] Populate the VMap entry correctly when default generated through lookup
During runtime unrolling on loops with multiple exits, we update the
exit blocks with the correct phi values from both original and remainder
loop.
In this process, we lookup the VMap for the mapped incoming phi values,
but did not update the VMap if a default entry was generated in the VMap
during the lookup. This default value is generated when constants or
values outside the current loop are looked up.
This patch fixes the assertion failure when null entries are present in
the VMap because of this lookup. Added a testcase that showcases the
problem.

llvm-svn: 313358
2017-09-15 13:29:33 +00:00
Ilya Biryukov d23faa843e Revert "[SLPVectorizer] Failure to beneficially vectorize 'copyable' elements in integer binary ops."
This reverts commit r313348.

Reason: it caused buildbot failures.
llvm-svn: 313352
2017-09-15 10:15:00 +00:00
Dinar Temirbulatov e2358b53bc [SLPVectorizer] Failure to beneficially vectorize 'copyable' elements in integer binary ops.
Patch tries to improve vectorization of the following code:

void add1(int * __restrict dst, const int * __restrict src) {
  *dst++ = *src++;
  *dst++ = *src++ + 1;
  *dst++ = *src++ + 2;
  *dst++ = *src++ + 3;
}
Allows to vectorize even if the very first operation is not a binary add, but just a load.

Reviewers: spatel, mzolotukhin, mkuper, hfinkel, RKSimon, filcab, ABataev, davide

Subscribers: llvm-commits, RKSimon

Differential Revision: https://reviews.llvm.org/D28907

llvm-svn: 313348
2017-09-15 06:56:39 +00:00
Dinar Temirbulatov bb891b864c [SLPVectorizer] Remove duplicated functionality code in initScheduleData function, NFCI.
llvm-svn: 313341
2017-09-15 04:31:54 +00:00
Alina Sbirlea 7ed5856a32 Refactor collectChildrenInLoop to LoopUtils [NFC]
Summary: Move to LoopUtils method that collects all children of a node inside a loop.

Reviewers: majnemer, sanjoy

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D37870

llvm-svn: 313322
2017-09-15 00:04:16 +00:00
Dehao Chen 3a81f84d9a Invoke GetInlineCost for legality check before inline functions in SampleProfileLoader.
Summary: SampleProfileLoader inlines hot functions if it is inlined in the profiled binary. However, the inline needs to be guarded by legality check, otherwise it could lead to correctness issues.

Reviewers: eraman, davidxl

Reviewed By: eraman

Subscribers: vitalybuka, sanjoy, llvm-commits

Differential Revision: https://reviews.llvm.org/D37779

llvm-svn: 313277
2017-09-14 17:29:56 +00:00
Alon Kom 682cfc1d4c [LV] Fix maximum legal VF calculation
This patch fixes pr34283, which exposed that the computation of
maximum legal width for vectorization was wrong, because it relied
on MaxInterleaveFactor to obtain the maximum stride used in the loop,
however not all strided accesses in the loop have an interleave-group
associated with them.
Instead of recording the maximum stride in the loop, which can be over
conservative (e.g. if the access with the maximum stride is not involved
in the dependence limitation), this patch tracks the actual maximum legal
width imposed by accesses that are involved in dependencies.

Differential Revision: https://reviews.llvm.org/D37507

llvm-svn: 313237
2017-09-14 07:40:02 +00:00
Vitaly Buka 48624d327a Revert "Invoke GetInlineCost for legality check before inline functions in SampleProfileLoader."
Patch introduced uninitialized value.

This reverts commit r313195.

llvm-svn: 313230
2017-09-14 05:40:33 +00:00
Peter Collingbourne cfbd089237 Reland r313157, "ThinLTO: Correctly follow aliasee references when dead stripping." which was reverted in r313222.
This reland includes a fix for the LowerTypeTests pass so that it
looks past aliases when determining which type identifiers are live.

Differential Revision: https://reviews.llvm.org/D37842

llvm-svn: 313229
2017-09-14 05:02:59 +00:00
Dinar Temirbulatov df0b843875 [SLPVectorizer] Prefer auto over explicit type for VL0, NFCI.
llvm-svn: 313228
2017-09-14 04:28:35 +00:00
Hans Wennborg ae050afeb9 Revert r313157 "ThinLTO: Correctly follow aliasee references when dead stripping."
This broke Chromium's CFI build; see crbug.com/765004.

> We were previously handling aliases during dead stripping by adding
> the aliased global's "original name" GUID to the worklist. This will
> lead to incorrect behaviour if the global has local linkage because
> the original name GUID will not correspond to the global's GUID in
> the summary.
>
> Because an alias is just another name for the global that it
> references, there is no need to mark the referenced global as used,
> or to follow references from any other copies of the global. So all
> we need to do is to follow references from the aliasee's summary
> instead of the alias.
>
> Differential Revision: https://reviews.llvm.org/D37789

llvm-svn: 313222
2017-09-14 00:40:14 +00:00
Eugene Zelenko 8002c504cd [Transforms] Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 313198
2017-09-13 21:43:53 +00:00
Dehao Chen 15c86ef970 Invoke GetInlineCost for legality check before inline functions in SampleProfileLoader.
Summary: SampleProfileLoader inlines hot functions if it is inlined in the profiled binary. However, the inline needs to be guarded by legality check, otherwise it could lead to correctness issues.

Reviewers: eraman, davidxl

Reviewed By: eraman

Subscribers: sanjoy, llvm-commits

Differential Revision: https://reviews.llvm.org/D37779

llvm-svn: 313195
2017-09-13 21:22:55 +00:00
Anna Thomas 19529f75b9 [LV] Avoid computing the register usage for default VF. NFC
These are changes to reduce redundant computations when calculating a
feasible vectorization factor:
1. early return when target has no vector registers
2. don't compute register usage for the default VF.

Suggested during review for D37702.

llvm-svn: 313176
2017-09-13 19:35:45 +00:00
Hiroshi Yamauchi a43913cfaf Add options to dump PGO counts in text.
Summary:
Added text options to -pgo-view-counts and -pgo-view-raw-counts that dump block frequency and branch probability info in text.

This is useful when the graph is very large and complex (the dot command crashes, lines/edges too close to tell apart, hard to navigate without textual search) or simply when text is preferred.

Reviewers: davidxl

Reviewed By: davidxl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D37776

llvm-svn: 313159
2017-09-13 17:20:38 +00:00
Peter Collingbourne d067c8ed59 ThinLTO: Correctly follow aliasee references when dead stripping.
We were previously handling aliases during dead stripping by adding
the aliased global's "original name" GUID to the worklist. This will
lead to incorrect behaviour if the global has local linkage because
the original name GUID will not correspond to the global's GUID in
the summary.

Because an alias is just another name for the global that it
references, there is no need to mark the referenced global as used,
or to follow references from any other copies of the global. So all
we need to do is to follow references from the aliasee's summary
instead of the alias.

Differential Revision: https://reviews.llvm.org/D37789

llvm-svn: 313157
2017-09-13 17:09:20 +00:00
Teresa Johnson 1958083d35 [ThinLTO] For SamplePGO, need to handle ICP targets consistently in thin link
Summary:
SamplePGO indirect call profiles record the target as the original GUID
for statics. The importer had special handling to map to the normal GUID
in that case. The dead global analysis needs the same treatment or
inconsistencies arise, resulting in linker unsats due to some dead
symbols being exported and kept, leaving in references to other dead
symbols that are removed.

This can happen when a SamplePGO profile collected by one binary is used
for a different binary, so the indirect call profiles may not accurately
reflect live targets.

Reviewers: danielcdh

Subscribers: mehdi_amini, inglorion, llvm-commits, eraman

Differential Revision: https://reviews.llvm.org/D37783

llvm-svn: 313151
2017-09-13 15:16:38 +00:00
Ayal Zaks e2a8c0758f [LV] Fix PR34523 - avoid generating redundant selects
When converting a PHI into a series of 'select' instructions to combine the
incoming values together according their edge masks, initialize the first
value to the incoming value In0 of the first predecessor, instead of
generating a redundant assignment 'select(Cond[0], In0, In0)'. The latter
fails when the Cond[0] mask is null, representing a full mask, which can
happen only when there's a single incoming value.

No functional changes intended nor expected other than surviving null Cond[0]'s.

This fix follows D35725, which introduced using null to represent full masks.

Differential Revision: https://reviews.llvm.org/D37619

llvm-svn: 313119
2017-09-13 06:28:37 +00:00
Aditya Kumar dfa8741c96 [GVNHoist] Factor out reachability to search for anticipable instructions quickly
Factor out the reachability such that multiple queries to find reachability of values are fast. This is based on finding
the ANTIC points
in the CFG which do not change during hoisting. The ANTIC points are basically the dominance-frontiers in the inverse
graph. So we introduce a data structure (CHI nodes)
to keep track of values flowing out of a basic block. We only do this for values with multiple occurrences in the
function as they are the potential hoistable candidates.

This patch allows us to hoist instructions to a basic block with >2 successors, as well as deal with infinite loops in a
trivial way.
Relevant test cases are added to show the functionality as well as regression fixes from PR32821.

Regression from previous GVNHoist:
We do not hoist fully redundant expressions because fully redundant expressions are already handled by NewGVN

Differential Revision: https://reviews.llvm.org/D35918
Reviewers: dberlin, sebpop, gberry,

llvm-svn: 313116
2017-09-13 05:28:03 +00:00
Reid Kleckner 8a1cd91016 [InstCombine] Add a flag to disable LowerDbgDeclare
Summary:
This should improve optimized debug info for address-taken variables at
the cost of inaccurate debug info in some situations.

We patched this into clang and deployed this change to Chromium
developers, and this significantly improved debuggability of optimized
code. The long-term solution to PR34136 seems more and more like it's
going to take a while, so I would like to commit this change under a
flag so that it can be used as a stop-gap measure.

This flag should really help so for C++ aggregates like std::string and
std::vector, which are typically address-taken, even after inlining, and
cannot be SROA-ed.

Reviewers: aprantl, dblaikie, probinson, dberlin

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D36596

llvm-svn: 313108
2017-09-13 01:43:25 +00:00
Dehao Chen f3ed14d323 Refactor the code to pass down ACT to SampleProfileLoader correctly.
Summary: This change passes down ACT to SampleProfileLoader for the new PM. Also remove the default value for SampleProfileLoader class as it is not used.

Reviewers: eraman, davidxl

Reviewed By: eraman

Subscribers: sanjoy, llvm-commits

Differential Revision: https://reviews.llvm.org/D37773

llvm-svn: 313080
2017-09-12 21:55:55 +00:00
Alina Sbirlea 80b806bf30 Make promoteLoopAccessesToScalars independent of AliasSet [NFC]
Summary:
The current promoteLoopAccessesToScalars method receives an AliasSet, but
the information used is in fact a list of Value*, known to must alias.
Create the list ahead of time to make this method independent of the AliasSet class.

While there is no functionality change, this adds overhead for creating
a set of Value*, when promotion would normally exit earlier.
This is meant to be as a first refactoring step in order to start replacing
AliasSetTracker with MemorySSA.
And while the end goal is to redesign LICM, the first few steps will focus on
adding MemorySSA as an alternative to the AliasSetTracker using most of the
existing functionality.

Reviewers: mkuper, danielcdh, dberlin

Subscribers: sanjoy, chandlerc, gberry, davide, llvm-commits

Differential Revision: https://reviews.llvm.org/D35439

llvm-svn: 313075
2017-09-12 21:18:44 +00:00
Anna Thomas 9f1be02fa3 [LV] Clamp the VF to the trip count
Summary:
When the MaxVectorSize > ConstantTripCount, we should just clamp the
vectorization factor to be the ConstantTripCount.
This vectorizes loops where the TinyTripCountThreshold >= TripCount < MaxVF.

Earlier we were finding the maximum vector width, which could be greater than
the trip count itself. The Loop vectorizer does all the work for generating a
vectorizable loop, but in the end we would always choose the scalar loop (since
the VF > trip count). This allows us to choose the VF keeping in mind the trip
count if available.

This is a fix on top of rL312472.

Reviewers: Ayal, zvi, hfinkel, dneilson

Reviewed by: Ayal

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D37702

llvm-svn: 313046
2017-09-12 16:32:45 +00:00
Alexey Bataev a26d3e834d [SLP] Fix for PHINode during horizontal reduction scanning, NFC.
Reduces number of loops during instructions analysis.

llvm-svn: 313035
2017-09-12 15:13:50 +00:00
Peter Collingbourne b9b6025328 LowerTypeTests: Add import/export support for targets without absolute symbol constants.
The rationale is the same as for r312967.

Differential Revision: https://reviews.llvm.org/D37408

llvm-svn: 312968
2017-09-11 22:49:10 +00:00
Peter Collingbourne b15a35e604 WholeProgramDevirt: Add import/export support for targets without absolute symbol constants.
Not all targets support the use of absolute symbols to export
constants. In particular, ARM has a wide variety of constant encodings
that cannot currently be relocated by linkers. So instead of exporting
the constants using symbols, export them directly in the summary.
The values of the constants are left as zeroes on targets that support
symbolic exports.

This may result in more cache misses when targeting those architectures
as a result of arbitrary changes in constant values, but this seems
somewhat unavoidable for now.

Differential Revision: https://reviews.llvm.org/D37407

llvm-svn: 312967
2017-09-11 22:34:42 +00:00
Uriel Korach 18972237a2 Test commit
llvm-svn: 312878
2017-09-10 08:31:22 +00:00
Nuno Lopes 404f106d71 Merge isKnownNonNull into isKnownNonZero
It now knows the tricks of both functions.
Also, fix a bug that considered allocas of non-zero address space to be always non null

Differential Revision: https://reviews.llvm.org/D37628

llvm-svn: 312869
2017-09-09 18:23:11 +00:00
Sanjay Patel 6fd4391ddd [DivRempairs] add a pass to optimize div/rem pairs (PR31028)
This is intended to be a superset of the functionality from D31037 (EarlyCSE) but implemented 
as an independent pass, so there's no stretching of scope and feature creep for an existing pass. 
I also proposed a weaker version of this for SimplifyCFG in D30910. And I initially had almost 
this same functionality as an addition to CGP in the motivating example of PR31028:
https://bugs.llvm.org/show_bug.cgi?id=31028

The advantage of positioning this ahead of SimplifyCFG in the pass pipeline is that it can allow 
more flattening. But it needs to be after passes (InstCombine) that could sink a div/rem and
undo the hoisting that is done here.

Decomposing remainder may allow removing some code from the backend (PPC and possibly others).

Differential Revision: https://reviews.llvm.org/D37121 

llvm-svn: 312862
2017-09-09 13:38:18 +00:00
Kostya Serebryany 4192b96313 [sanitizer-coverage] call appendToUsed once per module, not once per function (which is too slow)
llvm-svn: 312855
2017-09-09 05:30:13 +00:00
Alexey Bataev 628fbcae4c [SLP] Fix buildbots, NFC.
llvm-svn: 312853
2017-09-09 02:08:45 +00:00
Dinar Temirbulatov 0d31f0af43 [SLPVectorizer] Add struct InstructionsState that holds information about analysis of vector to be vectorized.
Reviewers: spatel, mzolotukhin, mkuper, hfinkel, RKSimon, filcab, ABataev, davide

Subscribers: llvm-commits, rengolin

Differential Revision: https://reviews.llvm.org/D37212

llvm-svn: 312802
2017-09-08 17:08:17 +00:00
Alexey Bataev bd4a361739 [SLP] Fix the warning about paths not returning the value, NFC.
llvm-svn: 312793
2017-09-08 14:32:20 +00:00
Alexey Bataev 6dd29fccb8 [SLP] Support for horizontal min/max reduction.
SLP vectorizer supports horizontal reductions for Add/FAdd binary
operations. Patch adds support for horizontal min/max reductions.
Function getReductionCost() is split to getArithmeticReductionCost() for
binary operation reductions and getMinMaxReductionCost() for min/max
reductions.
Patch fixes PR26956.

Differential revision: https://reviews.llvm.org/D27846

llvm-svn: 312791
2017-09-08 13:49:36 +00:00
Max Kazantsev d7b0f74c64 Re-enable "[IRCE] Identify loops with latch comparison against current IV value"
Re-applying after the found bug was fixed.

Differential Revision: https://reviews.llvm.org/D36215

llvm-svn: 312783
2017-09-08 10:15:05 +00:00
Max Kazantsev 57db44838d diff --git a/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp b/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp
index f72a808..9fa49fd 100644
--- a/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp
+++ b/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp
@@ -450,20 +450,10 @@ struct LoopStructure {
   // equivalent to:
   //
   // intN_ty inc = IndVarIncreasing ? 1 : -1;
-  // pred_ty predicate = IndVarIncreasing
-  //                         ? IsSignedPredicate ? ICMP_SLT : ICMP_ULT
-  //                         : IsSignedPredicate ? ICMP_SGT : ICMP_UGT;
+  // pred_ty predicate = IndVarIncreasing ? ICMP_SLT : ICMP_SGT;
   //
-  //
-  // for (intN_ty iv = IndVarStart; predicate(IndVarBase, LoopExitAt);
-  //      iv = IndVarNext)
+  // for (intN_ty iv = IndVarStart; predicate(iv, LoopExitAt); iv = IndVarBase)
   //   ... body ...
-  //
-  // Here IndVarBase is either current or next value of the induction variable.
-  // in the former case, IsIndVarNext = false and IndVarBase points to the
-  // Phi node of the induction variable. Otherwise, IsIndVarNext = true and
-  // IndVarBase points to IV increment instruction.
-  //
 
   Value *IndVarBase;
   Value *IndVarStart;
@@ -471,13 +461,12 @@ struct LoopStructure {
   Value *LoopExitAt;
   bool IndVarIncreasing;
   bool IsSignedPredicate;
-  bool IsIndVarNext;
 
   LoopStructure()
       : Tag(""), Header(nullptr), Latch(nullptr), LatchBr(nullptr),
         LatchExit(nullptr), LatchBrExitIdx(-1), IndVarBase(nullptr),
         IndVarStart(nullptr), IndVarStep(nullptr), LoopExitAt(nullptr),
-        IndVarIncreasing(false), IsSignedPredicate(true), IsIndVarNext(false) {}
+        IndVarIncreasing(false), IsSignedPredicate(true) {}
 
   template <typename M> LoopStructure map(M Map) const {
     LoopStructure Result;
@@ -493,7 +482,6 @@ struct LoopStructure {
     Result.LoopExitAt = Map(LoopExitAt);
     Result.IndVarIncreasing = IndVarIncreasing;
     Result.IsSignedPredicate = IsSignedPredicate;
-    Result.IsIndVarNext = IsIndVarNext;
     return Result;
   }
 
@@ -841,42 +829,21 @@ LoopStructure::parseLoopStructure(ScalarEvolution &SE,
     return false;
   };
 
-  // `ICI` can either be a comparison against IV or a comparison of IV.next.
-  // Depending on the interpretation, we calculate the start value differently.
+  // `ICI` is interpreted as taking the backedge if the *next* value of the
+  // induction variable satisfies some constraint.
 
-  // Pair {IndVarBase; IsIndVarNext} semantically designates whether the latch
-  // comparisons happens against the IV before or after its value is
-  // incremented. Two valid combinations for them are:
-  //
-  // 1) { phi [ iv.start, preheader ], [ iv.next, latch ]; false },
-  // 2) { iv.next; true }.
-  //
-  // The latch comparison happens against IndVarBase which can be either current
-  // or next value of the induction variable.
   const SCEVAddRecExpr *IndVarBase = cast<SCEVAddRecExpr>(LeftSCEV);
   bool IsIncreasing = false;
   bool IsSignedPredicate = true;
-  bool IsIndVarNext = false;
   ConstantInt *StepCI;
   if (!IsInductionVar(IndVarBase, IsIncreasing, StepCI)) {
     FailureReason = "LHS in icmp not induction variable";
     return None;
   }
 
-  const SCEV *IndVarStart = nullptr;
-  // TODO: Currently we only handle comparison against IV, but we can extend
-  // this analysis to be able to deal with comparison against sext(iv) and such.
-  if (isa<PHINode>(LeftValue) &&
-      cast<PHINode>(LeftValue)->getParent() == Header)
-    // The comparison is made against current IV value.
-    IndVarStart = IndVarBase->getStart();
-  else {
-    // Assume that the comparison is made against next IV value.
-    const SCEV *StartNext = IndVarBase->getStart();
-    const SCEV *Addend = SE.getNegativeSCEV(IndVarBase->getStepRecurrence(SE));
-    IndVarStart = SE.getAddExpr(StartNext, Addend);
-    IsIndVarNext = true;
-  }
+  const SCEV *StartNext = IndVarBase->getStart();
+  const SCEV *Addend = SE.getNegativeSCEV(IndVarBase->getStepRecurrence(SE));
+  const SCEV *IndVarStart = SE.getAddExpr(StartNext, Addend);
   const SCEV *Step = SE.getSCEV(StepCI);
 
   ConstantInt *One = ConstantInt::get(IndVarTy, 1);
@@ -1060,7 +1027,6 @@ LoopStructure::parseLoopStructure(ScalarEvolution &SE,
   Result.IndVarIncreasing = IsIncreasing;
   Result.LoopExitAt = RightValue;
   Result.IsSignedPredicate = IsSignedPredicate;
-  Result.IsIndVarNext = IsIndVarNext;
 
   FailureReason = nullptr;
 
@@ -1350,9 +1316,8 @@ LoopConstrainer::RewrittenRangeInfo LoopConstrainer::changeIterationSpaceEnd(
                                       BranchToContinuation);
 
     NewPHI->addIncoming(PN->getIncomingValueForBlock(Preheader), Preheader);
-    auto *FixupValue =
-        LS.IsIndVarNext ? PN->getIncomingValueForBlock(LS.Latch) : PN;
-    NewPHI->addIncoming(FixupValue, RRI.ExitSelector);
+    NewPHI->addIncoming(PN->getIncomingValueForBlock(LS.Latch),
+                        RRI.ExitSelector);
     RRI.PHIValuesAtPseudoExit.push_back(NewPHI);
   }
 
@@ -1735,10 +1700,7 @@ bool InductiveRangeCheckElimination::runOnLoop(Loop *L, LPPassManager &LPM) {
   }
   LoopStructure LS = MaybeLoopStructure.getValue();
   const SCEVAddRecExpr *IndVar =
-      cast<SCEVAddRecExpr>(SE.getSCEV(LS.IndVarBase));
-  if (LS.IsIndVarNext)
-    IndVar = cast<SCEVAddRecExpr>(SE.getMinusSCEV(IndVar,
-                                                  SE.getSCEV(LS.IndVarStep)));
+      cast<SCEVAddRecExpr>(SE.getMinusSCEV(SE.getSCEV(LS.IndVarBase), SE.getSCEV(LS.IndVarStep)));
 
   Optional<InductiveRangeCheck::Range> SafeIterRange;
   Instruction *ExprInsertPt = Preheader->getTerminator();
diff --git a/test/Transforms/IRCE/latch-comparison-against-current-value.ll b/test/Transforms/IRCE/latch-comparison-against-current-value.ll
deleted file mode 100644
index afea0e6..0000000
--- a/test/Transforms/IRCE/latch-comparison-against-current-value.ll
+++ /dev/null
@@ -1,182 +0,0 @@
-; RUN: opt -verify-loop-info -irce-print-changed-loops -irce -S < %s 2>&1 | FileCheck %s
-
-; Check that IRCE is able to deal with loops where the latch comparison is
-; done against current value of the IV, not the IV.next.
-
-; CHECK: irce: in function test_01: constrained Loop at depth 1 containing: %loop<header><exiting>,%in.bounds<latch><exiting>
-; CHECK: irce: in function test_02: constrained Loop at depth 1 containing: %loop<header><exiting>,%in.bounds<latch><exiting>
-; CHECK-NOT: irce: in function test_03: constrained Loop at depth 1 containing: %loop<header><exiting>,%in.bounds<latch><exiting>
-; CHECK-NOT: irce: in function test_04: constrained Loop at depth 1 containing: %loop<header><exiting>,%in.bounds<latch><exiting>
-
-; SLT condition for increasing loop from 0 to 100.
-define void @test_01(i32* %arr, i32* %a_len_ptr) #0 {
-
-; CHECK:      test_01
-; CHECK:        entry:
-; CHECK-NEXT:     %exit.mainloop.at = load i32, i32* %a_len_ptr, !range !0
-; CHECK-NEXT:     [[COND2:%[^ ]+]] = icmp slt i32 0, %exit.mainloop.at
-; CHECK-NEXT:     br i1 [[COND2]], label %loop.preheader, label %main.pseudo.exit
-; CHECK:        loop:
-; CHECK-NEXT:     %idx = phi i32 [ %idx.next, %in.bounds ], [ 0, %loop.preheader ]
-; CHECK-NEXT:     %idx.next = add nuw nsw i32 %idx, 1
-; CHECK-NEXT:     %abc = icmp slt i32 %idx, %exit.mainloop.at
-; CHECK-NEXT:     br i1 true, label %in.bounds, label %out.of.bounds.loopexit1
-; CHECK:        in.bounds:
-; CHECK-NEXT:     %addr = getelementptr i32, i32* %arr, i32 %idx
-; CHECK-NEXT:     store i32 0, i32* %addr
-; CHECK-NEXT:     %next = icmp slt i32 %idx, 100
-; CHECK-NEXT:     [[COND3:%[^ ]+]] = icmp slt i32 %idx, %exit.mainloop.at
-; CHECK-NEXT:     br i1 [[COND3]], label %loop, label %main.exit.selector
-; CHECK:        main.exit.selector:
-; CHECK-NEXT:     %idx.lcssa = phi i32 [ %idx, %in.bounds ]
-; CHECK-NEXT:     [[COND4:%[^ ]+]] = icmp slt i32 %idx.lcssa, 100
-; CHECK-NEXT:     br i1 [[COND4]], label %main.pseudo.exit, label %exit
-; CHECK-NOT: loop.preloop:
-; CHECK:        loop.postloop:
-; CHECK-NEXT:    %idx.postloop = phi i32 [ %idx.copy, %postloop ], [ %idx.next.postloop, %in.bounds.postloop ]
-; CHECK-NEXT:     %idx.next.postloop = add nuw nsw i32 %idx.postloop, 1
-; CHECK-NEXT:     %abc.postloop = icmp slt i32 %idx.postloop, %exit.mainloop.at
-; CHECK-NEXT:     br i1 %abc.postloop, label %in.bounds.postloop, label %out.of.bounds.loopexit
-
-entry:
-  %len = load i32, i32* %a_len_ptr, !range !0
-  br label %loop
-
-loop:
-  %idx = phi i32 [ 0, %entry ], [ %idx.next, %in.bounds ]
-  %idx.next = add nsw nuw i32 %idx, 1
-  %abc = icmp slt i32 %idx, %len
-  br i1 %abc, label %in.bounds, label %out.of.bounds
-
-in.bounds:
-  %addr = getelementptr i32, i32* %arr, i32 %idx
-  store i32 0, i32* %addr
-  %next = icmp slt i32 %idx, 100
-  br i1 %next, label %loop, label %exit
-
-out.of.bounds:
-  ret void
-
-exit:
-  ret void
-}
-
-; ULT condition for increasing loop from 0 to 100.
-define void @test_02(i32* %arr, i32* %a_len_ptr) #0 {
-
-; CHECK:      test_02
-; CHECK:        entry:
-; CHECK-NEXT:     %exit.mainloop.at = load i32, i32* %a_len_ptr, !range !0
-; CHECK-NEXT:     [[COND2:%[^ ]+]] = icmp ult i32 0, %exit.mainloop.at
-; CHECK-NEXT:     br i1 [[COND2]], label %loop.preheader, label %main.pseudo.exit
-; CHECK:        loop:
-; CHECK-NEXT:     %idx = phi i32 [ %idx.next, %in.bounds ], [ 0, %loop.preheader ]
-; CHECK-NEXT:     %idx.next = add nuw nsw i32 %idx, 1
-; CHECK-NEXT:     %abc = icmp ult i32 %idx, %exit.mainloop.at
-; CHECK-NEXT:     br i1 true, label %in.bounds, label %out.of.bounds.loopexit1
-; CHECK:        in.bounds:
-; CHECK-NEXT:     %addr = getelementptr i32, i32* %arr, i32 %idx
-; CHECK-NEXT:     store i32 0, i32* %addr
-; CHECK-NEXT:     %next = icmp ult i32 %idx, 100
-; CHECK-NEXT:     [[COND3:%[^ ]+]] = icmp ult i32 %idx, %exit.mainloop.at
-; CHECK-NEXT:     br i1 [[COND3]], label %loop, label %main.exit.selector
-; CHECK:        main.exit.selector:
-; CHECK-NEXT:     %idx.lcssa = phi i32 [ %idx, %in.bounds ]
-; CHECK-NEXT:     [[COND4:%[^ ]+]] = icmp ult i32 %idx.lcssa, 100
-; CHECK-NEXT:     br i1 [[COND4]], label %main.pseudo.exit, label %exit
-; CHECK-NOT: loop.preloop:
-; CHECK:        loop.postloop:
-; CHECK-NEXT:    %idx.postloop = phi i32 [ %idx.copy, %postloop ], [ %idx.next.postloop, %in.bounds.postloop ]
-; CHECK-NEXT:     %idx.next.postloop = add nuw nsw i32 %idx.postloop, 1
-; CHECK-NEXT:     %abc.postloop = icmp ult i32 %idx.postloop, %exit.mainloop.at
-; CHECK-NEXT:     br i1 %abc.postloop, label %in.bounds.postloop, label %out.of.bounds.loopexit
-
-entry:
-  %len = load i32, i32* %a_len_ptr, !range !0
-  br label %loop
-
-loop:
-  %idx = phi i32 [ 0, %entry ], [ %idx.next, %in.bounds ]
-  %idx.next = add nsw nuw i32 %idx, 1
-  %abc = icmp ult i32 %idx, %len
-  br i1 %abc, label %in.bounds, label %out.of.bounds
-
-in.bounds:
-  %addr = getelementptr i32, i32* %arr, i32 %idx
-  store i32 0, i32* %addr
-  %next = icmp ult i32 %idx, 100
-  br i1 %next, label %loop, label %exit
-
-out.of.bounds:
-  ret void
-
-exit:
-  ret void
-}
-
-; Same as test_01, but comparison happens against IV extended to a wider type.
-; This test ensures that IRCE rejects it and does not falsely assume that it was
-; a comparison against iv.next.
-; TODO: We can actually extend the recognition to cover this case.
-define void @test_03(i32* %arr, i64* %a_len_ptr) #0 {
-
-; CHECK:      test_03
-
-entry:
-  %len = load i64, i64* %a_len_ptr, !range !1
-  br label %loop
-
-loop:
-  %idx = phi i32 [ 0, %entry ], [ %idx.next, %in.bounds ]
-  %idx.next = add nsw nuw i32 %idx, 1
-  %idx.ext = sext i32 %idx to i64
-  %abc = icmp slt i64 %idx.ext, %len
-  br i1 %abc, label %in.bounds, label %out.of.bounds
-
-in.bounds:
-  %addr = getelementptr i32, i32* %arr, i32 %idx
-  store i32 0, i32* %addr
-  %next = icmp slt i32 %idx, 100
-  br i1 %next, label %loop, label %exit
-
-out.of.bounds:
-  ret void
-
-exit:
-  ret void
-}
-
-; Same as test_02, but comparison happens against IV extended to a wider type.
-; This test ensures that IRCE rejects it and does not falsely assume that it was
-; a comparison against iv.next.
-; TODO: We can actually extend the recognition to cover this case.
-define void @test_04(i32* %arr, i64* %a_len_ptr) #0 {
-
-; CHECK:      test_04
-
-entry:
-  %len = load i64, i64* %a_len_ptr, !range !1
-  br label %loop
-
-loop:
-  %idx = phi i32 [ 0, %entry ], [ %idx.next, %in.bounds ]
-  %idx.next = add nsw nuw i32 %idx, 1
-  %idx.ext = sext i32 %idx to i64
-  %abc = icmp ult i64 %idx.ext, %len
-  br i1 %abc, label %in.bounds, label %out.of.bounds
-
-in.bounds:
-  %addr = getelementptr i32, i32* %arr, i32 %idx
-  store i32 0, i32* %addr
-  %next = icmp ult i32 %idx, 100
-  br i1 %next, label %loop, label %exit
-
-out.of.bounds:
-  ret void
-
-exit:
-  ret void
-}
-
-!0 = !{i32 0, i32 50}
-!1 = !{i64 0, i64 50}

llvm-svn: 312775
2017-09-08 04:26:41 +00:00
Peter Collingbourne 88a58cf9e7 WholeProgramDevirt: When promoting for single-impl devirt, also rename the comdat.
This is required when targeting COFF, as the comdat name must match
one of the names of the symbols in the comdat.

Differential Revision: https://reviews.llvm.org/D37550

llvm-svn: 312767
2017-09-08 00:10:53 +00:00
Reid Kleckner 0e8c4bb055 Sink some IntrinsicInst.h and Intrinsics.h out of llvm/include
Many of these uses can get by with forward declarations. Hopefully this
speeds up compilation after adding a single intrinsic.

llvm-svn: 312759
2017-09-07 23:27:44 +00:00
Richard Trieu c7828ebea4 Revert r312318, r312325, r312424, r312489
r312318 - Debug info for variables whose type is shrinked to bool
r312325, r312424, r312489 - Test case for r312318

Revision 312318 introduced a null dereference bug.
Details in https://bugs.llvm.org/show_bug.cgi?id=34490

llvm-svn: 312758
2017-09-07 23:20:35 +00:00
Krzysztof Parzyszek 1dc313727e Disable jump threading into loop headers
Consider this type of a loop:
    for (...) {
      ...
      if (...) continue;
      ...
    }
Normally, the "continue" would branch to the loop control code that
checks whether the loop should continue iterating and which contains
the (often) unique loop latch branch. In certain cases jump threading
can "thread" the inner branch directly to the loop header, creating
a second loop latch. Loop canonicalization would then transform this
loop into a loop nest. The problem with this is that in such a loop
nest neither loop is countable even if the original loop was. This
may inhibit subsequent loop optimizations and be detrimental to
performance.

Differential Revision: https://reviews.llvm.org/D36404

llvm-svn: 312664
2017-09-06 19:36:58 +00:00
Sanjay Patel 6840c5ff75 [ValueTracking, InstCombine] canonicalize fcmp ord/uno with non-NAN ops to null constants
This is a preliminary step towards solving the remaining part of PR27145 - IR for isfinite():
https://bugs.llvm.org/show_bug.cgi?id=27145

In order to solve that one more generally, we need to add matching for and/or of fcmp ord/uno
with a constant operand.

But while looking at those patterns, I realized we were missing a canonicalization for nonzero
constants. Rather than limiting to just folds for constants, we're adding a general value
tracking method for this based on an existing DAG helper.

By transforming everything to 0.0, we can simplify the existing code in foldLogicOfFCmps()
and pick up missing vector folds.

Differential Revision: https://reviews.llvm.org/D37427

llvm-svn: 312591
2017-09-05 23:13:13 +00:00
Davide Italiano 32504cf661 [GVNHoist] Move duplicated code to a helper function. NFCI.
llvm-svn: 312575
2017-09-05 20:49:41 +00:00
Craig Topper 28d6d962d5 [InstCombine] Move foldSelectICmpAnd helper function earlier in the file to enable reuse in a future patch.
llvm-svn: 312518
2017-09-05 05:26:37 +00:00
Craig Topper 4c766a0559 [InstCombine] In foldSelectIntoOp, avoid creating a Constant before we know for sure we're going to use it and avoid an unnecessary call to m_APInt.
Instead of creating a Constant and then calling m_APInt with it (which will always return true). Just create an APInt initially, and use that for the checks in isSelect01 function. If it turns out we do need the Constant, create it from the APInt.

This is a refactor for a future patch that will do some more checks of the constant values here.

llvm-svn: 312517
2017-09-05 05:26:36 +00:00
Daniel Berlin f9c9455d3f NewGVN: Fix PR 34430 - we need to look through predicateinfo copies to detect self-cycles of phi nodes. We also need to not ignore certain types of arguments when testing whether the phi has a backedge or was originally constant.
llvm-svn: 312510
2017-09-05 02:17:43 +00:00
Daniel Berlin 54a92fcc5d NewGVN: Fix PR 34452 by passing instruction all the way down when we do aggregate value simplification
llvm-svn: 312509
2017-09-05 02:17:42 +00:00
Daniel Berlin 1a58258232 NewGVN: Detect copies through predicateinfo
llvm-svn: 312508
2017-09-05 02:17:41 +00:00
Daniel Berlin 4ad7e8d263 NewGVN: Change where check for original instruction in phi of ops leader finding is done. Where we had it before, we would stop looking when we hit the original instruction, but skip it. Now we skip it and keep looking.
llvm-svn: 312507
2017-09-05 02:17:40 +00:00
Zvi Rackover 9a087a357a LoopVectorize: MaxVF should not be larger than the loop trip count
Summary:
Improve how MaxVF is computed while taking into account that MaxVF should not be larger than the loop's trip count.

Other than saving on compile-time by pruning the possible MaxVF candidates, this patch fixes pr34438 which exposed the following flow:
1. Short trip count identified -> Don't bail out, set OptForSize:=True to avoid tail-loop and runtime checks.
2. Compute MaxVF returned 16 on a target supporting AVX512.
3. OptForSize -> choose VF:=MaxVF.
4. Bail out because TripCount = 8, VF = 16, TripCount % VF !=0 means we need a tail loop.

With this patch step 2. will choose MaxVF=8 based on TripCount.

Reviewers: Ayal, dorit, mkuper, hfinkel

Reviewed By: hfinkel

Subscribers: hfinkel, llvm-commits

Differential Revision: https://reviews.llvm.org/D37425

llvm-svn: 312472
2017-09-04 08:35:13 +00:00
Sam Parker 7cd826a321 [LoopUnroll][DebugInfo] Don't add metadata to unrolled remainder loop
Debug information can be, and was, corrupted when the runtime
remainder loop was fully unrolled. This is because a !null node can
be created instead of a unique one describing the loop. In this case,
the original node gets incorrectly updated with the NewLoopID
metadata.

In the case when the remainder loop is going to be quickly fully
unrolled, there isn't the need to add loop metadata for it anyway.

Differential Revision: https://reviews.llvm.org/D37338

llvm-svn: 312471
2017-09-04 08:12:16 +00:00
Sanjay Patel bc6da4e40f [InstCombine] replace unnecessary fcmp fold with assert
See https://reviews.llvm.org/rL312411 for related InstSimplify tests.

llvm-svn: 312421
2017-09-02 18:10:29 +00:00
Sanjay Patel 64fc5daf42 [InstCombine] combine foldAndOfFCmps and foldOrOfFcmps; NFCI
In addition to removing chunks of duplicated code, we don't
want these to diverge. If there's a fold for one, there
should be a fold of the other via DeMorgan's Laws.

llvm-svn: 312420
2017-09-02 17:53:33 +00:00
Sanjay Patel 275bb5a14e [InstCombine] fix misnamed locals and use them to reduce code; NFCI
We had these locals:
Value *Op0RHS = LHS->getOperand(1);
Value *Op1LHS = RHS->getOperand(0);
...so we confusingly transposed the meaning of left/right and op0/op1.

llvm-svn: 312418
2017-09-02 17:17:17 +00:00
Benjamin Kramer 14ddcdfb18 [LoopVectorize] Turn static DenseSet into switch.
LLVM transforms this into a bit test which is a lot faster and smaller.

llvm-svn: 312417
2017-09-02 16:41:55 +00:00
Sanjay Patel da6f9b2fee [InstCombine] remove unnecessary code; NFC
llvm-svn: 312416
2017-09-02 16:32:37 +00:00
Sanjay Patel 4c52f765a5 [InstCombine] move related functions next to each other; NFC
This makes it easier to see that they're almost duplicates.
As with the similar icmp functions, there should be identical 
folds for both logic ops because those are DeMorganized variants.

llvm-svn: 312415
2017-09-02 16:30:27 +00:00
Sanjay Patel 6b139464ca [InstCombine] use local variable to reduce code duplication; NFCI
llvm-svn: 312414
2017-09-02 15:11:55 +00:00
Daniel Berlin 94090dd13b Fix PR/33305. caused by trying to simplify expressions in phi of ops that should have no leaders.
Summary:
After a discussion with Rekka, i believe this (or a small variant)
should fix the remaining phi-of-ops problems.

Rekka's algorithm for completeness relies on looking up expressions
that should have no leader, and expecting it to fail (IE looking up
expressions that can't exist in a predecessor, and expecting it to
find nothing).

Unfortunately, sometimes these expressions can be simplified to
constants, but we need the lookup to fail anyway.  Additionally, our
simplifier outsmarts this by taking these "not quite right"
expressions, and simplifying them into other expressions or walking
through phis, etc.  In the past, we've sometimes been able to find
leaders for these expressions, incorrectly.

This change causes us to not to try to phi of ops such expressions.
We determine safety by seeing if they depend on a phi node in our
block.

This is not perfect, we can do a bit better, but this should be a
"correctness start" that we can then improve.  It also requires a
bunch of caching that i'll eventually like to eliminate.

The right solution, longer term, to the simplifier issues, is to make
the query interface for the instruction simplifier/constant folder
have the flags we need, so that we can keep most things going, but
turn off the possibly-invalid parts (threading through phis, etc).
This is an issue in another wrong code bug as well.

Reviewers: davide, mcrosier

Subscribers: sanjoy, llvm-commits

Differential Revision: https://reviews.llvm.org/D37175

llvm-svn: 312401
2017-09-02 02:18:44 +00:00
Eugene Zelenko 75075efe5e [Analysis, Transforms] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 312383
2017-09-01 21:37:29 +00:00
Craig Topper 924f20262b [InstCombine][InstSimplify] Teach decomposeBitTestICmp to look through truncate instructions
This patch teaches decomposeBitTestICmp to look through truncate instructions on the input to the compare. If a truncate is found it will now return the pre-truncated Value and appropriately extend the APInt mask.

This allows some code to be removed from InstSimplify that was doing this functionality.

This allows InstCombine's bit test combining code to match a pre-truncate Value with the same Value appear with an 'and' on another icmp. Or it allows us to combine a truncate to i16 and a truncate to i8. This also required removing the type check from the beginning of getMaskedTypeForICmpPair, but I believe that's ok because we still have to find two values from the input to each icmp that are equal before we'll do any transformation. So the type check was really just serving as an early out.

There was one user of decomposeBitTestICmp that didn't want to look through truncates, so I've added a flag to prevent that behavior when necessary.

Differential Revision: https://reviews.llvm.org/D37158

llvm-svn: 312382
2017-09-01 21:27:34 +00:00
Craig Topper d3b465606a [InstCombine] Don't require the compare types to be the same in getMaskedTypeForICmpPair.
A future patch will make the code look through truncates feeding the compare. So the compares might be different types but the pretruncated types might be the same.

This should be safe because we still require the same Value* to be used truncated or not in both compares. So that serves to ensure the types are the same.

llvm-svn: 312381
2017-09-01 21:27:31 +00:00
Craig Topper 085c1f4dea [InstCombine] When converting decomposeBitTestICmp's APInt return to ConstantInt, make sure we use the type from the Value* that was also returned from decomposeBitTestICmp.
Previously we used the type from the LHS of the compare, but a future patch will change decomposeBitTestICmp to look through truncates so it will return a pretruncated Value* and the type needs to match that.

llvm-svn: 312380
2017-09-01 21:27:29 +00:00
Daniel Berlin 86932104db NewGVN: Make sure we don't incorrectly use PredicateInfo when doing PHI of ops
Summary: When we backtranslate expressions, we can't use the predicateinfo, since we are evaluating them in a different context.

Reviewers: davide, mcrosier

Subscribers: sanjoy, Prazek, llvm-commits

Differential Revision: https://reviews.llvm.org/D37174

llvm-svn: 312352
2017-09-01 19:20:18 +00:00
Manoj Gupta 6b54c7e11b [LoopVectorizer] Use two step casting for float to pointer types.
Summary:
LoopVectorizer is creating casts between vec<ptr> and vec<float> types
on ARM when compiling OpenCV. Since, tIs is illegal to directly cast a
floating point type to a pointer type even if the types have same size
causing a crash. Fix the crash using a two-step casting by bitcasting
to integer and integer to pointer/float.
Fixes PR33804.

Reviewers: mkuper, Ayal, dlj, rengolin, srhines

Reviewed By: rengolin

Subscribers: aemerson, kristof.beyls, mkazantsev, Meinersbur, rengolin, mzolotukhin, llvm-commits

Differential Revision: https://reviews.llvm.org/D35498

llvm-svn: 312331
2017-09-01 15:36:00 +00:00
Clement Courbet bc0c4459c9 [MergeICmps] Fix build of rL312315 on clang-with-thin-lto-windows:
MergeICmps.cpp(68,15): error: chosen constructor is explicit in copy-initialization
      return {};
APInt.h(339,12): note: explicit constructor declared here
  explicit APInt() : BitWidth(1) { U.VAL = 0; }
             ^
MergeICmps.cpp(56,9): note: in implicit initialization of field 'Offset' with omitted
initializer
  APInt Offset;
          ^

llvm-svn: 312326
2017-09-01 11:51:23 +00:00
Clement Courbet 65130e2d8d Reland rL312315: [MergeICmps] MergeICmps is a new optimization pass that turns chains of integer
Add missing header.

This reverts commit 86dd6335cf7607af22f383a9a8e072ba929848cf.

llvm-svn: 312322
2017-09-01 10:56:34 +00:00
Strahinja Petrovic 676fd0b022 Debug info for variables whose type is shrinked to bool
This patch provides such debug information for integer
variables whose type is shrinked to bool by providing 
dwarf expression which returns either constant initial 
value or other value.

Patch by Nikola Prica.

Differential Revision: https://reviews.llvm.org/D35994

llvm-svn: 312318
2017-09-01 10:05:27 +00:00
Clement Courbet 316212575b Revert "[MergeICmps] MergeICmps is a new optimization pass that turns chains of integer"
Break build

This reverts commit d07ab866f7f88f81e49046d691a80dcd32d7198b.

llvm-svn: 312317
2017-09-01 09:43:08 +00:00
Clement Courbet 9473c01e96 [MergeICmps] MergeICmps is a new optimization pass that turns chains of integer
comparisons into memcmp.

Thanks to recent improvements in the LLVM codegen, the memcmp is typically
inlined as a chain of efficient hardware comparisons.
This typically benefits C++ member or nonmember operator==().

For now this is disabled by default until:
 - https://bugs.llvm.org/show_bug.cgi?id=33329 is complete
 - Benchmarks show that this is always useful.

Differential Revision:
https://reviews.llvm.org/D33987

llvm-svn: 312315
2017-09-01 09:07:05 +00:00
Eugene Zelenko fa6434bebb [Analysis] Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes. Also affected in files (NFC).
llvm-svn: 312289
2017-08-31 21:56:16 +00:00
Akira Hatanaka 13d2beb14d [ObjCARC] Pass the correct BasicBlock to fix assertion failure.
The BasicBlock passed to FindPredecessorRetainWithSafePath should be the
parent block of Autorelease. This fixes a crash that occurs in
FindDependencies when StartInst is not in StartBB.

rdar://problem/33866381

llvm-svn: 312266
2017-08-31 18:27:47 +00:00
Sanjay Patel e6b48a1b02 [InstCombine] improve demanded vector elements analysis of insertelement
Recurse instead of returning on the first found optimization. Also, return early in the caller
instead of continuing because that allows another round of simplification before we might
potentially lose undef information from a shuffle mask by eliminating the shuffle.

As noted in the review, we could probably do better and be more efficient by moving all of
demanded elements into a separate pass, but this is yet another quick fix to instcombine.

Differential Revision: https://reviews.llvm.org/D37236

llvm-svn: 312248
2017-08-31 15:57:17 +00:00
Dinar Temirbulatov 8870a14e4e [SLPVectorizer] Move out Entry->NeedToGather check and assert of inner loop as invariant, NFCI.
llvm-svn: 312242
2017-08-31 14:10:07 +00:00
Max Kazantsev 0a9c1ef2eb [IRCE] Identify loops with latch comparison against current IV value
Current implementation of parseLoopStructure interprets the latch comparison as a
comarison against `iv.next`. If the actual comparison is made against the `iv` current value
then the loop may be rejected, because this misinterpretation leads to incorrect evaluation
of the latch start value.

This patch teaches the IRCE to distinguish this kind of loops and perform the optimization
for them. Now we use `IndVarBase` variable which can be either next or current value of the
induction variable (previously we used `IndVarNext` which was always the value on next iteration).

Differential Revision: https://reviews.llvm.org/D36215

llvm-svn: 312221
2017-08-31 07:04:20 +00:00
Max Kazantsev a22742be5a [IRCE][NFC] Rename IndVarNext to IndVarBase
Renaming as a preparation step to generalizing IRCE for comparison not only against
the next value of an indvar, but also against the current.

Differential Revision: https://reviews.llvm.org/D36509

llvm-svn: 312215
2017-08-31 05:58:15 +00:00
Adrian Prantl 504b82d44b Don't add a fragment expression when GlobalSRA splits up a single-member struct
Fixes PR34390.

https://bugs.llvm.org/show_bug.cgi?id=34390

llvm-svn: 312196
2017-08-31 00:06:18 +00:00
Matt Morehouse 034126e507 [SanitizeCoverage] Enable stack-depth coverage for -fsanitize=fuzzer
Summary:
- Don't sanitize __sancov_lowest_stack.
- Don't instrument leaf functions.
- Add CoverageStackDepth to Fuzzer and FuzzerNoLink.
- Only enable on Linux.

Reviewers: vitalybuka, kcc, george.karpenkov

Reviewed By: kcc

Subscribers: kubamracek, cfe-commits, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37156

llvm-svn: 312185
2017-08-30 22:49:31 +00:00
Adrian Prantl b192b545c1 Refactor DIBuilder::createFragmentExpression into a static DIExpression member
NFC

llvm-svn: 312165
2017-08-30 20:04:17 +00:00
Daniel Berlin 23fec57e6f NewGVN: Make sure we add the correct user if we swapped the comparison operands
llvm-svn: 312162
2017-08-30 19:53:23 +00:00
Daniel Berlin 7ef26daba8 NewGVN: Allow simplification into variables
llvm-svn: 312161
2017-08-30 19:52:39 +00:00
Benjamin Kramer b99d7c9214 [GVNSink] Remove dependency on SmallPtrSet iteration order.
Found by LLVM_ENABLE_REVERSE_ITERATION.

llvm-svn: 312156
2017-08-30 18:46:37 +00:00
Sanjay Patel 6f7ac7e402 [InstCombine] remove unnecessary vector select fold; NFCI
This code is double-dead:
1. We simplify all selects with constant true/false condition in InstSimplify.
   I've minimized/moved the tests to show that works as expected.
2. All remaining vector selects with a constant condition are canonicalized to
   shufflevector, so we really can't see this pattern.

llvm-svn: 312123
2017-08-30 14:04:57 +00:00
Florian Hahn b992feee13 [InstCombine] Fold insert sequence if first ins has multiple users.
Summary:
If the first insertelement instruction has multiple users and inserts at
position 0, we can re-use this instruction when folding a chain of
insertelement instructions. As we need to generate the first
insertelement instruction anyways, this should be a strict improvement.

We could get rid of the restriction of inserting at position 0 by
creating a different shufflemask, but it is probably worth to keep the
first insertelement instruction with position 0, as this is easier to do
efficiently than at other positions I think.

Reviewers: grosser, mkuper, fpetrogalli, efriedma

Reviewed By: fpetrogalli

Subscribers: gareevroman, llvm-commits

Differential Revision: https://reviews.llvm.org/D37064

llvm-svn: 312110
2017-08-30 10:54:21 +00:00
Mandeep Singh Grang e3bbb68b0c [cfi] Fixed non-determinism in codegen due to DenseSet iteration order
llvm-svn: 312098
2017-08-30 04:47:21 +00:00
Evgeniy Stepanov 7372b67063 [cfi] Avoid branch veneers in jump tables when possible.
Summary:
When jumptable encoding does not match target code encoding (arm vs
thumb), a veneer is inserted by the linker. We can not avoid this
in all cases, because entries within one jumptable must have the same
encoding, but we can make it less common by selecting the jumptable
encoding to match the majority of its targets.

This change only covers FullLTO, and not ThinLTO.

Reviewers: pcc

Subscribers: aemerson, mehdi_amini, javed.absar, kristof.beyls, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37171

llvm-svn: 312054
2017-08-29 22:40:19 +00:00
Evgeniy Stepanov 4731ad81c7 [cfi] Build __cfi_check as Thumb when applicable.
Summary:
Cross-DSO CFI needs all __cfi_check exports to use the same encoding
(ARM vs Thumb).

Reviewers: pcc

Subscribers: aemerson, srhines, kristof.beyls, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D37243

llvm-svn: 312052
2017-08-29 22:29:15 +00:00
Matt Morehouse ba2e61b357 Revert "[SanitizeCoverage] Enable stack-depth coverage for -fsanitize=fuzzer"
This reverts r312026 due to bot breakage.

llvm-svn: 312047
2017-08-29 21:56:56 +00:00
Wei Mi ebb9327759 [LoopUnswitch] Fix a simple bug which disables loop unswitch for select statement
This is to fix PR34257. rL309059 takes an early return when FindLIVLoopCondition
fails to find a loop invariant condition. This is wrong and it will disable loop
unswitch for select. The patch fixes the bug.

Differential Revision: https://reviews.llvm.org/D36985

llvm-svn: 312045
2017-08-29 21:45:11 +00:00
Benjamin Kramer 154411e0e7 [FunctionImport] Avoid unused variable warnings in Release builds
Just skip the entire block in NDEBUG. No functionality change intended.

llvm-svn: 312031
2017-08-29 20:24:39 +00:00
Alexey Bataev 978e2e4760 [SimplifyCFG] Fix for PR34219: Preserve alignment after merging conditional stores.
Summary:
If SimplifyCFG pass is able to merge conditional stores into single one,
it loses the alignment. This may lead to incorrect codegen. Patch
sets the alignment of the new instruction if it is set in the original
one.

Reviewers: jmolloy

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D36841

llvm-svn: 312030
2017-08-29 20:06:24 +00:00
Matt Morehouse 2ad8d948b2 [SanitizeCoverage] Enable stack-depth coverage for -fsanitize=fuzzer
Summary:
- Don't sanitize __sancov_lowest_stack.
- Don't instrument leaf functions.
- Add CoverageStackDepth to Fuzzer and FuzzerNoLink.
- Disable stack depth tracking on Mac.

Reviewers: vitalybuka, kcc, george.karpenkov

Reviewed By: kcc

Subscribers: kubamracek, cfe-commits, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37156

llvm-svn: 312026
2017-08-29 19:48:12 +00:00
Craig Topper 4431bfe88c [InstCombine] Support vector splats in transformZExtICmp
This patch adds splat support to transformZExtICmp. The test cases are vector versions of tests that failed when commenting out parts of the existing scalar code.

One test didn't vectorize optimize properly due to another bug so a TODO has been added.

Differential Revision: https://reviews.llvm.org/D37253

llvm-svn: 312023
2017-08-29 18:58:13 +00:00
Teresa Johnson 2df7fc7991 [ThinLTO] Clean up stale alias import handling
Summary:
Remove some code that was no longer needed. The first FIXME is
stale since we long ago started using the index to drive importing,
rather than doing force importing based on linkage type. And
now with r309278, we no longer import any aliases.

Reviewers: dblaikie

Subscribers: inglorion, llvm-commits

Differential Revision: https://reviews.llvm.org/D37266

llvm-svn: 312019
2017-08-29 18:15:34 +00:00
Dehao Chen efd007f6f4 Add null check for promoted direct call
Summary: We originally assume that in pgo-icp, the promoted direct call will never be null after strip point casts. However, stripPointerCasts is so smart that it could possibly return the value of the function call if it knows that the return value is always an argument. In this case, the returned value cannot cast to Instruction. In this patch, null check is added to ensure null pointer will not be accessed.

Reviewers: tejohnson, xur, davidxl, djasper

Reviewed By: tejohnson

Subscribers: llvm-commits, sanjoy

Differential Revision: https://reviews.llvm.org/D37252

llvm-svn: 312005
2017-08-29 15:28:12 +00:00
Sanjay Patel 674d2c23ea [Instruction] add moveAfter() convenience function; NFCI
As suggested in D37121, here's a wrapper for removeFromParent() + insertAfter(),
but implemented using moveBefore() for symmetry/efficiency.

Differential Revision: https://reviews.llvm.org/D37239

llvm-svn: 312001
2017-08-29 14:07:48 +00:00
Max Kazantsev bb1d010872 [LSR] Fix Shadow IV in case of integer overflow
When LSR processes code like

  int accumulator = 0;
  for (int i = 0; i < N; i++) {
    accummulator += i;
    use((double) accummulator);
  }

It may decide to replace integer `accumulator` with a double Shadow IV to get rid
of casts.  The problem with that is that the `accumulator`'s value may overflow.
Starting from this moment, the behavior of integer and double accumulators
will differ.

This patch strenghtens up the conditions of Shadow IV mechanism applicability.
We only allow it for IVs that are proved to be `AddRec`s with `nsw`/`nuw` flag.

Differential Revision: https://reviews.llvm.org/D37209

llvm-svn: 311986
2017-08-29 07:32:20 +00:00
Craig Topper 5d6ddda92d [InstCombine] Teach foldSelectICmpAndOr to handle vector splats
This was pretty close to working already. While I was here I went ahead and passed the ICmpInst pointer from the caller instead of doing a dyn_cast that can never fail.

Differential Revision: https://reviews.llvm.org/D37237

llvm-svn: 311960
2017-08-29 00:13:49 +00:00
Justin Bogner f1a54a47b0 [sanitizer-coverage] Mark the guard and 8-bit counter arrays as used
In r311742 we marked the PCs array as used so it wouldn't be dead
stripped, but left the guard and 8-bit counters arrays alone since
these are referenced by the coverage instrumentation. This doesn't
quite work if we want the indices of the PCs array to match the other
arrays though, since elements can still end up being dead and
disappear.

Instead, we mark all three of these arrays as used so that they'll be
consistent with one another.

llvm-svn: 311959
2017-08-29 00:11:05 +00:00
Justin Bogner 873a0746f1 [sanitizer-coverage] Return the array from CreatePCArray. NFC
Be more consistent with CreateFunctionLocalArrayInSection in the API
of CreatePCArray, and assign the member variable in the caller like we
do for the guard and 8-bit counter arrays.

This also tweaks the order of method declarations to match the order
of definitions in the file.

llvm-svn: 311955
2017-08-28 23:46:11 +00:00
Justin Bogner be757de2b6 [sanitizer-coverage] Clean up trailing whitespace. NFC
llvm-svn: 311954
2017-08-28 23:38:12 +00:00
Kamil Rytarowski a9f404f813 Define NetBSD/amd64 ASAN Shadow Offset
Summary:
Catch up after compiler-rt changes and define kNetBSD_ShadowOffset64
as (1ULL << 46).
 
Sponsored by <The NetBSD Foundation>

Reviewers: kcc, joerg, filcab, vitalybuka, eugenis

Reviewed By: eugenis

Subscribers: llvm-commits, #sanitizers

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D37234

llvm-svn: 311941
2017-08-28 22:13:52 +00:00
Craig Topper 516e39cd38 [InstCombine] Teach select01 helper of foldSelectIntoOp to handle vector splats
We were handling some vectors in foldSelectIntoOp, but not if the operand of the bin op was any kind of vector constant. This patch fixes it to treat vector splats the same as scalars.

Differential Revision: https://reviews.llvm.org/D37232

llvm-svn: 311940
2017-08-28 22:00:27 +00:00
Davide Italiano 20cb7e887f [LoopUnroll] Properly update loop structure in case of successful peeling.
When peeling kicks in, it updates the loop preheader.
Later, a successful full unroll of the loop needs to update a PHI
which i-th argument comes from the loop preheader, so it'd better look
at the correct block. Fixes PR33437.

Differential Revision:  https://reviews.llvm.org/D37153

llvm-svn: 311922
2017-08-28 20:29:33 +00:00
Davide Italiano 9a09ae448d [LoopUnroll] Add a cl::opt to force peeling, for testing purposes.
Will be used to test the patch proposed in D37153.

llvm-svn: 311915
2017-08-28 19:50:55 +00:00
Taewook Oh 572f45a3c8 Create PHI node for the return value only when the return value has uses.
Summary:
Currently, a phi node is created in the normal destination to unify the return values from promoted calls and the original indirect call. This patch makes this phi node to be created only when the return value has uses.

This patch is necessary to generate valid code, as compiler crashes with the attached test case without this patch. Without this patch, an illegal phi node that has no incoming value from `entry`/`catch` is created in `cleanup` block.

I think existing implementation is good as far as there is at least one use of the original indirect call. `insertCallRetPHI` creates a new phi node in the normal destination block only when the original indirect call dominates its use and the normal destination block. Otherwise, `fixupPHINodeForNormalDest` will handle the unification of return values naturally without creating a new phi node. However, if there's no use, `insertCallRetPHI` still creates a new phi node even when the original indirect call does not dominate the normal destination block, because `getCallRetPHINode` returns false.

Reviewers: xur, davidxl, danielcdh

Reviewed By: xur

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D37176

llvm-svn: 311906
2017-08-28 18:57:00 +00:00
Craig Topper 3763f0e00d [InstCombine] Call hasNoSignedWrap instead of hasNoUnsignedWrap to get the NSW flag when handling Add in SimplifyDemandedUseBits.
This is a typo from r311789.

This should fix PR34349.

llvm-svn: 311902
2017-08-28 18:44:28 +00:00
NAKAMURA Takumi a1e97a77f5 Untabify.
llvm-svn: 311875
2017-08-28 06:47:47 +00:00
Dehao Chen 191b24d3d2 revert r310985 which breaks for the following case:
struct string {
  ~string();
};
void f2();
void f1(int) { f2(); }
void run(int c) {
  string body;
  while (true) {
    if (c)
      f1(c);
    else
      f1(c);
  }
}

Will recommit once the issue is fixed.

llvm-svn: 311864
2017-08-27 22:22:39 +00:00
Ayal Zaks 1f58dda4e4 [LV] Fix PR34248 - recommit D32871 after revert r311304
Original commit r311077 of D32871 was reverted in r311304 due to failures
reported in PR34248.

This recommit fixes PR34248 by restricting the packing of predicated scalars
into vectors only when vectorizing, avoiding doing so when unrolling w/o
vectorizing. Added a test derived from the reproducer of PR34248.

llvm-svn: 311849
2017-08-27 12:55:46 +00:00
Davide Italiano 9bdccb37d5 [NewGVN] Use `auto` when the type is obvious NFCI.
llvm-svn: 311838
2017-08-26 22:31:10 +00:00
Daniel Berlin de269f4620 NewGVN: Fix PR33204 - We need to add memory users when we bypass memorydefs for loads, not just when we do it for stores.
llvm-svn: 311829
2017-08-26 07:37:11 +00:00
Davide Italiano a872519dbd [Inliner] Only compute fully inline cost when remarks are enabled.
Prior to this change (and after r311371), we computed it
unconditionally, causin gsevere compile time regressions (in some
cases, 5 to 10x).

llvm-svn: 311804
2017-08-25 22:01:42 +00:00
Matt Morehouse 6ec7595b1e Revert "[SanitizeCoverage] Enable stack-depth coverage for -fsanitize=fuzzer"
This reverts r311801 due to a bot failure.

llvm-svn: 311803
2017-08-25 22:01:21 +00:00
Matt Morehouse f42bd31323 [SanitizeCoverage] Enable stack-depth coverage for -fsanitize=fuzzer
Summary:
- Don't sanitize __sancov_lowest_stack.
- Don't instrument leaf functions.
- Add CoverageStackDepth to Fuzzer and FuzzerNoLink.

Reviewers: vitalybuka, kcc

Reviewed By: kcc

Subscribers: cfe-commits, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37156

llvm-svn: 311801
2017-08-25 21:18:29 +00:00
Kostya Serebryany d3e4b7e24a [sanitizer-coverage] extend fsanitize-coverage=pc-table with flags for every PC
llvm-svn: 311794
2017-08-25 19:29:47 +00:00
Craig Topper 35171e5d67 [InstCombine] Don't fall back to only calling computeKnownBits if the upper bit of Add/Sub is demanded.
Just create an all 1s demanded mask and continue recursing like normal. The recursive calls should be able to handle an all 1s mask and do the right thing.

The only time we should care about knowing whether the upper bit was demanded is when we need to know if we should clear the NSW/NUW flags.

Now that we have a consistent path through the code for all cases, use KnownBits::computeForAddSub to compute the known bits at the end since we already have the LHS and RHS.

My larger goal here is to move the code that turns add into xor if only 1 bit is demanded and no bits below it are non-zero from InstCombiner::OptAndOp to here. This will allow it to be more general instead of just looking for 'add' and 'and' with constant RHS.

Differential Revision: https://reviews.llvm.org/D36486

llvm-svn: 311789
2017-08-25 18:39:40 +00:00
Florian Hahn cd78345398 [LoopInterchange] Skip zext instructions when looking for induction var.
Summary:
SimplifyIndVar may introduce zext instructions to widen arguments of the
loop exit check. They should not prevent us from splitting the loop at
the induction variable, but maybe the check should be more conservative,
e.g. making sure it only extends arguments used by a comparison?

Reviewers: karthikthecool, mcrosier, mzolotukhin

Reviewed By: mcrosier

Subscribers: mzolotukhin, llvm-commits

Differential Revision: https://reviews.llvm.org/D34879

llvm-svn: 311783
2017-08-25 16:52:29 +00:00
Amjad Aboud 22178dd33b [InstCombine] Consider more cases where SimplifyDemandedUseBits does not convert AShr to LShr.
There are cases where AShr have better chance to be optimized than LShr, especially when the demanded bits are not known to be Zero, and also known to be similar to the sign bit.

Differential Revision: https://reviews.llvm.org/D36936

llvm-svn: 311773
2017-08-25 11:07:54 +00:00
Gor Nishanov e29e94cf87 [coroutines] Add support for symmetric control transfer (musttail on coro.resumes followed by a suspend)
Summary:
Add musttail to any resume instructions that is immediately followed by a
suspend (i.e. ret). We do this even in -O0 to support guaranteed tail call
for symmetrical coroutine control transfer (C++ Coroutines TS extension).
This transformation is done only in the resume part of the coroutine that has
identical signature and calling convention as the coro.resume call.

Reviewers: GorNishanov

Reviewed By: GorNishanov

Subscribers: EricWF, majnemer, llvm-commits

Differential Revision: https://reviews.llvm.org/D37125

llvm-svn: 311751
2017-08-25 02:25:10 +00:00
Justin Bogner ad96ff1228 [sanitizer-coverage] Make sure pc-tables aren't dead stripped
Add a reference to the PC array in llvm.used so that linkers that
aggressively dead strip (like ld64) don't remove it.

llvm-svn: 311742
2017-08-25 01:24:54 +00:00
Xinliang David Li 66531dd10a [Profile] backward propagate profile info in JumpThreading
Take-2 after fixing bugs in the original patch.

Differential Revsion: http://reviews.llvm.org/D36864

llvm-svn: 311727
2017-08-24 22:54:01 +00:00
Sanjay Patel bb789381fc [InstCombine] fix and enhance udiv/urem narrowing
There are 3 small independent changes here:

  1. Account for multiple uses in the pattern matching: avoid the transform if it increases the instruction count.
  2. Add a missing fold for the case where the numerator is the constant: http://rise4fun.com/Alive/E2p
  3. Enable all folds for vector types.

There's still one more potential change - use "shouldChangeType()" to keep from transforming to an illegal integer type.

Differential Revision: https://reviews.llvm.org/D36988

llvm-svn: 311726
2017-08-24 22:54:01 +00:00
Chad Rosier f98335e0b0 [PartialInlining] Formatting. NFC.
llvm-svn: 311702
2017-08-24 21:21:09 +00:00
Chad Rosier 4cb2e82774 [PartialInlining] Type. NFC.
llvm-svn: 311699
2017-08-24 20:29:02 +00:00
Sanjay Patel 5d67d8916e [BypassSlowDivision] move map helper code to header; NFC
We can reuse this code with other div/rem transforms as shown in:
https://reviews.llvm.org/D31037 
https://bugs.llvm.org/show_bug.cgi?id=31028

llvm-svn: 311661
2017-08-24 14:43:33 +00:00
Mikael Holmen 7a99e33b8e [Reassociate] Do not drop debug location if replacement is missing
Summary:
When reassociating an expression, do not drop the instruction's
original debug location in case the replacement location is
missing.

The debug location must at least not be dropped for inlinable
callsites of debug-info-bearing functions in debug-info-bearing
functions. Failing to do so would result in an "inlinable function "
"call in a function with debug info must have a !dbg location"
error in the verifier.

As preserving the original debug location is not expected
to result in overly jumpy debug line information, it is
preserved for all other cases too.

This fixes PR34231:
https://bugs.llvm.org/show_bug.cgi?id=34231

Original patch by David Stenberg

Reviewers: davide, craig.topper, mcrosier, dblaikie, aprantl

Reviewed By: davide, aprantl

Subscribers: aprantl

Differential Revision: https://reviews.llvm.org/D36865

llvm-svn: 311642
2017-08-24 09:05:00 +00:00
Daniel Berlin f948603a15 NewGVN: We weren't properly simplifying selects with equal arguments due to a thinko.
llvm-svn: 311626
2017-08-24 02:43:17 +00:00
Rong Xu 15848e5977 [PGO] Set edge weights for indirectbr instruction with profile counts
Current PGO only annotates the edge weight for branch and switch instructions
with profile counts. We should also annotate the indirectbr instruction as
all the information is there. This patch enables the annotating for indirectbr
instructions. Also uses this annotation in branch probability analysis.

Differential Revision: https://reviews.llvm.org/D37074

llvm-svn: 311604
2017-08-23 21:36:02 +00:00
Hans Wennborg 66f6fc0a49 LowerAtomic: Don't skip optnone functions; atomic still need lowering (PR34020)
The lowering isn't really an optimization, so optnone shouldn't make a
difference. ARM relies on the pass running when using "-mthread-model
single", because in that mode, it doesn't run AtomicExpand. See bug for
more details.

Differential Revision: https://reviews.llvm.org/D37040

llvm-svn: 311565
2017-08-23 15:43:28 +00:00
Gor Nishanov 2f55b958b1 [coroutines] CoroBegin from inner coroutines should be considered for spills
Summary:
If a coroutine outer calls another coroutine inner and the inner coroutine body is inlined into the outer, coro.begin from the inner coroutine should be considered for spilling if accessed across suspends.

Prior to this change, coroutine frame building code was not considering any coro.begins for spilling.
With this change, we only ignore coro.begin for the current coroutine, but, any coro.begins that were inlined into the current coroutine are eligible for spills.

Fixes PR34267

Reviewers: GorNishanov

Subscribers: qcolombet, llvm-commits, EricWF

Differential Revision: https://reviews.llvm.org/D37062

llvm-svn: 311556
2017-08-23 14:47:52 +00:00
Chad Rosier 8db41e9dbd [Reassociate] Don't canonicalize x + (-Constant * y) -> x - (Constant * y)..
..if the resulting subtract will be broken up later.  This can cause us to get
into an infinite loop.

x + (-5.0 * y)      -> x - (5.0 * y)       ; Canonicalize neg const
x - (5.0 * y)       -> x + (0 - (5.0 * y)) ; Break up subtract
x + (0 - (5.0 * y)) -> x + (-5.0 * y)      ; Replace 0-X with X*-1.

PR34078

llvm-svn: 311554
2017-08-23 14:10:06 +00:00
Davide Italiano c78885818a [InstCombine] Fold branches with irrelevant conditions to a constant.
InstCombine folds instructions with irrelevant conditions to undef.
This, as Nuno confirmed is a bug.
(see https://bugs.llvm.org/show_bug.cgi?id=33409#c1 )

Given the original motivation for the change is that of removing an
USE, we now fold to false instead (which reaches the same goal
without undesired side effects).

Fixes PR33409.

Differential Revision:  https://reviews.llvm.org/D36975

llvm-svn: 311540
2017-08-23 09:14:37 +00:00
Craig Topper a85f86225a [InstCombine] Remove unused argument. NFC
llvm-svn: 311529
2017-08-23 05:46:09 +00:00
Craig Topper a94069fb4c [InstCombine] Replace a simple matcher with a plain old dyn_cast. NFC
llvm-svn: 311528
2017-08-23 05:46:08 +00:00
Craig Topper 524c44f74e [InstCombine] Remove an unnecessary dyn_cast to Instruction and a switch over two opcodes. Just dyn_cast to the specific instruction classes individually. NFC
Change the helper methods to take the more specific class as well.

llvm-svn: 311527
2017-08-23 05:46:07 +00:00
Craig Topper ec4b82571c [InstCombine] Remove check for sext of vector icmp from shouldOptimizeCast
Looks like for 'and' and 'or' we end up performing at least some of the transformations this is bocking in a round about way anyway.

For 'and sext(cmp1), sext(cmp2) we end up later turning it into 'select cmp1, sext(cmp2), 0'. Then we optimize that back to sext (and cmp1, cmp2). This is the same result we would have gotten if shouldOptimizeCast hadn't blocked it. We do something analogous for 'or'.

With this patch we allow that transformation to happen directly in foldCastedBitwiseLogic. And we now support the same thing for 'xor'. This is definitely opening up many other cases, but since we already went around it for some cases hopefully it's ok.

Differential Revision: https://reviews.llvm.org/D36213

llvm-svn: 311508
2017-08-22 23:40:15 +00:00
Peter Collingbourne 001052a067 WholeProgramDevirt: Create bitcast to i8* at each virtual call site.
We can't reuse the llvm.assume instruction's bitcast because it may not
dominate every user of the vtable pointer.

Differential Revision: https://reviews.llvm.org/D36994

llvm-svn: 311491
2017-08-22 21:41:19 +00:00
Matt Morehouse b1fa8255db [SanitizerCoverage] Optimize stack-depth instrumentation.
Summary:
Use the initialexec TLS type and eliminate calls to the TLS
wrapper.  Fixes the sanitizer-x86_64-linux-fuzzer bot failure.

Reviewers: vitalybuka, kcc

Reviewed By: kcc

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D37026

llvm-svn: 311490
2017-08-22 21:28:29 +00:00
Jakub Kuderski 2724d45325 [ADCE][Dominators] Reapply: Teach ADCE to preserve dominators
Summary:
This patch teaches ADCE to preserve both DominatorTrees and PostDominatorTrees.

This is reapplies the original patch r311057 that was reverted in r311381.
The previous version wasn't using the batch update api for updating dominators,
which in vary rare cases caused assertion failures.

This also fixes PR34258.

Reviewers: dberlin, chandlerc, sanjoy, davide, grosser, brzycki

Reviewed By: davide

Subscribers: grandinj, zhendongsu, llvm-commits, david2050

Differential Revision: https://reviews.llvm.org/D35869

llvm-svn: 311467
2017-08-22 16:30:21 +00:00
Craig Topper 775ffcc8f5 [InstCombine] Move the checks for pointer types in getMaskedTypeForICmpPair earlier in the function
I don't think there's any reason to have them scattered about and on all 4 operands. We already have an early check that both compares must be the same type. And within a given compare the LHS and RHS must have the same type. Beyond that I don't think there's anyway this function returns anything valid for pointer types. So let's just return early and be done with it.

Differential Revision: https://reviews.llvm.org/D36561

llvm-svn: 311383
2017-08-21 21:00:45 +00:00
Sanjoy Das 08a38fe71e Revert "Reapply: [ADCE][Dominators] Teach ADCE to preserve dominators"
Summary: This partially reverts commit r311057 since it breaks ADCE.  See PR34258.

Reviewers: kuhar

Subscribers: mcrosier, david2050, llvm-commits

Differential Revision: https://reviews.llvm.org/D36979

llvm-svn: 311381
2017-08-21 20:39:18 +00:00
Haicheng Wu 0812c5bea3 [InlineCost] Add cl::opt to allow full inline cost to be computed for debugging purposes.
Currently, the inline cost model will bail once the inline cost exceeds the
inline threshold in order to avoid unnecessary compile-time. However, when
debugging it is useful to compute the full cost, so this command line option
is added to override the default behavior.

I took over this work from Chad Rosier (mcrosier@codeaurora.org).

Differential Revision: https://reviews.llvm.org/D35850

llvm-svn: 311371
2017-08-21 20:00:09 +00:00
Sanjay Patel 82ec872990 [LibCallSimplifier] try harder to fold memcmp with constant arguments (2nd try)
The 1st try was reverted because it could inf-loop by creating a dead instruction.
Fixed that to not happen and added a test case to verify.

Original commit message:

Try to fold:
memcmp(X, C, ConstantLength) == 0 --> load X == *C

Without this change, we're unnecessarily checking the alignment of the constant data,
so we miss the transform in the first 2 tests in the patch.

I noted this shortcoming of LibCallSimpifier in one of the recent CGP memcmp expansion
patches. This doesn't help the example in:
https://bugs.llvm.org/show_bug.cgi?id=34032#c13
...directly, but it's worth short-circuiting more of these simple cases since we're
already trying to do that.

The benefit of transforming to load+cmp is that existing IR analysis/transforms may
further simplify that code. For example, if the load of the variable is common to
multiple memcmp calls, CSE can remove the duplicate instructions.

Differential Revision: https://reviews.llvm.org/D36922

llvm-svn: 311366
2017-08-21 19:13:14 +00:00
Craig Topper 74177e1ed1 [InstCombine] Teach foldSelectICmpAnd to recognize a (icmp slt X, 0) and (icmp sgt X, -1) as equivalent to an and with the sign bit of the truncated type
This is similar to what was already done in foldSelectICmpAndOr. Ultimately I'd like to see if we can call foldSelectICmpAnd from foldSelectIntoOp if we detect a power of 2 constant. This would allow us to remove foldSelectICmpAndOr entirely.

Differential Revision: https://reviews.llvm.org/D36498

llvm-svn: 311362
2017-08-21 19:02:06 +00:00
Sam Elliott e963c89d11 Migrate WholeProgramDevirt to new Optimization Remark API
Summary:
This is an attempt to move WholeProgramDevirt to the new remark API.

https://bugs.llvm.org/show_bug.cgi?id=33793

Reviewers: anemet

Reviewed By: anemet

Subscribers: fhahn, llvm-commits

Differential Revision: https://reviews.llvm.org/D36943

llvm-svn: 311352
2017-08-21 16:57:21 +00:00
Sam Elliott e604b563ea Emit only A Single Opt Remark When Inlining
Summary:
This updates the Inliner to only add a single Optimization
Remark when Inlining, rather than an Analysis Remark and an
Optimization Remark.

Fixes https://bugs.llvm.org/show_bug.cgi?id=33786

Reviewers: anemet, davidxl, chandlerc

Reviewed By: anemet

Subscribers: haicheng, fhahn, mehdi_amini, dblaikie, llvm-commits, eraman

Differential Revision: https://reviews.llvm.org/D36054

llvm-svn: 311349
2017-08-21 16:45:47 +00:00
Craig Topper cc255bcd77 [InstCombine] Fix a weakness in canEvaluateZExtd around 'and' instructions
Summary:
If the bitsToClear from the LHS of an 'and' comes back non-zero, but all of those bits are known zero on the RHS, we can reset bitsToClear.

Without this, the 'or' in the modified test case blocks the transform because it has non-zero bits in its RHS in those bits.

Reviewers: spatel, majnemer, davide

Reviewed By: davide

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D36944

llvm-svn: 311343
2017-08-21 16:04:11 +00:00
Xinliang David Li d2838fc4b9 Revert 311208, 311209
llvm-svn: 311341
2017-08-21 16:00:38 +00:00
Sanjay Patel 707f786cc5 revert r311333: [LibCallSimplifier] try harder to fold memcmp with constant arguments
We're getting lots of compile-timeout bot failures like:
http://lab.llvm.org:8011/builders/clang-native-arm-lnt/builds/7119
http://lab.llvm.org:8011/builders/clang-cmake-x86_64-avx2-linux

llvm-svn: 311340
2017-08-21 15:16:25 +00:00
Sanjay Patel 7756edfa93 [LibCallSimplifier] try harder to fold memcmp with constant arguments
Try to fold:
memcmp(X, C, ConstantLength) == 0 --> load X == *C

Without this change, we're unnecessarily checking the alignment of the constant data, 
so we miss the transform in the first 2 tests in the patch.

I noted this shortcoming of LibCallSimpifier in one of the recent CGP memcmp expansion 
patches. This doesn't help the example in:
https://bugs.llvm.org/show_bug.cgi?id=34032#c13
...directly, but it's worth short-circuiting more of these simple cases since we're 
already trying to do that.

The benefit of transforming to load+cmp is that existing IR analysis/transforms may
further simplify that code. For example, if the load of the variable is common to 
multiple memcmp calls, CSE can remove the duplicate instructions.

Differential Revision: https://reviews.llvm.org/D36922

llvm-svn: 311333
2017-08-21 13:55:49 +00:00
Chandler Carruth bd6dc14230 Revert r311077: [LV] Using VPlan ...
This causes LLVM to assert fail on PPC64 and crash / infloop in other
cases. Filed http://llvm.org/PR34248 with reproducer attached.

llvm-svn: 311304
2017-08-20 23:17:11 +00:00
Benjamin Kramer 2e5be849cc [Mem2Reg] Modernize code a bit.
No functionality change intended.

llvm-svn: 311290
2017-08-20 14:34:44 +00:00
Benjamin Kramer 49a49fe816 Move helper classes into anonymous namespaces.
No functionality change intended.

llvm-svn: 311288
2017-08-20 13:03:48 +00:00
Aditya Kumar a525fffd07 [Loop Vectorize] Added a separate metadata
Added a separate metadata to indicate when the loop
has already been vectorized instead of setting width and count to 1.

Patch written by Divya Shanmughan and Aditya Kumar

Differential Revision: https://reviews.llvm.org/D36220

llvm-svn: 311281
2017-08-20 10:32:41 +00:00
Sam Elliott 7fe0aaa140 Revert "Emit only A Single Opt Remark When Inlining"
Reverting due to clang build failure

llvm-svn: 311274
2017-08-20 06:55:10 +00:00
Sam Elliott 785dd75369 Emit only A Single Opt Remark When Inlining
Summary:
This updates the Inliner to only add a single Optimization
Remark when Inlining, rather than an Analysis Remark and an
Optimization Remark.

Fixes https://bugs.llvm.org/show_bug.cgi?id=33786

Reviewers: anemet, davidxl, chandlerc

Reviewed By: anemet

Subscribers: haicheng, fhahn, mehdi_amini, dblaikie, llvm-commits, eraman

Differential Revision: https://reviews.llvm.org/D36054

llvm-svn: 311273
2017-08-20 06:43:34 +00:00
Teresa Johnson 73305f82e9 [ThinLTO] Fix ThinLTO crash
Summary:
Follow up to fix in r311023, which fixed the case where the combined
index is written to disk. The same samplePGO logic exists for the
in-memory index when computing imports, so we need to filter out
GlobalVariable summaries there too.

Reviewers: davidxl

Subscribers: inglorion, llvm-commits

Differential Revision: https://reviews.llvm.org/D36919

llvm-svn: 311254
2017-08-19 18:04:25 +00:00
Chandler Carruth 4f3aa29a46 [Inliner] Fix a nasty bug when inlining a non-recursive trace of
a function into itself.

We tried to fix this before in r306495 but that got reverted as the
assert was actually hit.

This fixes the original bug (which we seem to have lost track of with
the revert) by blocking a second remapping when the function being
inlined is also the caller and the remapping could succeed but
erroneously.

The included test case would actually load from an inlined copy of the
alloca before this change, failing to load the stored value and
miscompiling.

Many thanks to Richard Smith for diagnosing a user miscompile to this
bug, and to Kyle for the first attempt and initial analysis and David Li
for remembering the issue and how to fix it and suggesting the patch.
I'm just stitching it together and landing it. =]

llvm-svn: 311229
2017-08-19 06:56:11 +00:00
Chandler Carruth 1f8212597d [SLP] Fix an unused variable warning in non-asserts builds.
llvm-svn: 311227
2017-08-19 05:06:23 +00:00
Dinar Temirbulatov 7aff8cfa55 [SLPVectorizer] Tighten up VLeft, VRight declaration, remove unnecessary testcase test/Transforms/SLPVectorizer/X86/reorder.ll, NFCI.
llvm-svn: 311223
2017-08-19 03:15:07 +00:00
Dinar Temirbulatov e3ce1b455e [SLPVectorizer] Add opcode parameter to reorderAltShuffleOperands, reorderInputsAccordingToOpcode functions.
Reviewers: mkuper, RKSimon, ABataev, mzolotukhin, spatel, filcab

Subscribers: llvm-commits, rengolin

Differential Revision: https://reviews.llvm.org/D36766

llvm-svn: 311221
2017-08-19 02:54:20 +00:00
Xinliang David Li 0d07f9d68a Fix comment /NFC
llvm-svn: 311209
2017-08-18 23:08:50 +00:00
Xinliang David Li 709ffe178e [Profile] backward propagate profile info in JumpThreading
Differential Revsion: http://reviews.llvm.org/D36864

llvm-svn: 311208
2017-08-18 23:00:05 +00:00
Max Kazantsev 0aaf8c16ac [IRCE] Fix buggy behavior in Clamp
Clamp function was too optimistic when choosing signed or unsigned min/max function for calculations.
In fact, `!IsSignedPredicate` guarantees us that `Smallest` and `Greatest` can be compared safely using unsigned
predicates, but we did not check this for `S` which can in theory be negative.

This patch makes Clamp use signed min/max for cases when it fails to prove `S` being non-negative,
and it adds a test where such situation may lead to incorrect conditions calculation.

Differential Revision: https://reviews.llvm.org/D36873

llvm-svn: 311205
2017-08-18 22:50:29 +00:00
Ana Pazos 6210f27dfc [PGO] Fixed assertion due to mismatched memcpy size type.
Summary:
Memcpy intrinsics have size argument of any integer type, like i32 or i64.
Fixed size type along with its value when cloning the intrinsic.

Reviewers: davidxl, xur

Reviewed By: davidxl

Subscribers: mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D36844

llvm-svn: 311188
2017-08-18 19:17:08 +00:00
Matt Morehouse 5c7fc76983 [SanitizerCoverage] Add stack depth tracing instrumentation.
Summary:
Augment SanitizerCoverage to insert maximum stack depth tracing for
use by libFuzzer.  The new instrumentation is enabled by the flag
-fsanitize-coverage=stack-depth and is compatible with the existing
trace-pc-guard coverage.  The user must also declare the following
global variable in their code:
  thread_local uintptr_t __sancov_lowest_stack

https://bugs.llvm.org/show_bug.cgi?id=33857

Reviewers: vitalybuka, kcc

Reviewed By: vitalybuka

Subscribers: kubamracek, hiraditya, cfe-commits, llvm-commits

Differential Revision: https://reviews.llvm.org/D36839

llvm-svn: 311186
2017-08-18 18:43:30 +00:00
Jakub Kuderski e608ef7635 [LoopRotate][Dominators] Use the incremental API to update DomTree
Summary: This patch teaches LoopRotate to use the new incremental API to update the DominatorTree.

Reviewers: dberlin, davide, grosser, sanjoy

Reviewed By: dberlin, davide

Subscribers: hiraditya, llvm-commits, mzolotukhin

Differential Revision: https://reviews.llvm.org/D35581

llvm-svn: 311125
2017-08-17 21:48:19 +00:00
Jakub Kuderski e35a449140 [Dominators] Teach LoopUnswitch to use the incremental API
Summary:
This patch makes LoopUnswitch use new incremental API for updating dominators.
It also updates SplitCriticalEdge, as it is called in LoopUnswitch.

There doesn't seem to be any noticeable performance difference when bootstrapping clang with this patch.

Reviewers: dberlin, davide, sanjoy, grosser, chandlerc

Reviewed By: davide, grosser

Subscribers: mzolotukhin, llvm-commits

Differential Revision: https://reviews.llvm.org/D35528

llvm-svn: 311093
2017-08-17 16:45:35 +00:00
Simon Dardis b5205c69d2 [dfsan] Add explicit zero extensions for shadow parameters in function wrappers.
In the case where dfsan provides a custom wrapper for a function,
shadow parameters are added for each parameter of the function.
These parameters are i16s. For targets which do not consider this
a legal type, the lack of sign extension information would cause
LLVM to generate anyexts around their usage with phi variables
and calling convention logic.

Address this by introducing zero exts for each shadow parameter.

Reviewers: pcc, slthakur

Differential Revision: https://reviews.llvm.org/D33349

llvm-svn: 311087
2017-08-17 14:14:25 +00:00
Ayal Zaks 6627883369 [LV] Using VPlan to model the vectorized code and drive its transformation
VPlan is an ongoing effort to refactor and extend the Loop Vectorizer. This
patch introduces the VPlan model into LV and uses it to represent the vectorized
code and drive the generation of vectorized IR.

In this patch VPlan models the vectorized loop body: the vectorized control-flow
is represented using VPlan's Hierarchical CFG, with predication refactored from
being a post-vectorization-step into a vectorization planning step modeling
if-then VPRegionBlocks, and generating code inline with non-predicated code. The
vectorized code within each VPBasicBlock is represented as a sequence of
Recipes, each responsible for modelling and generating a sequence of IR
instructions. To keep the size of this commit manageable the Recipes in this
patch are coarse-grained and capture large chunks of LV's code-generation logic.
The constructed VPlans are dumped in dot format under -debug.

This commit retains current vectorizer output, except for minor instruction
reorderings; see associated modifications to lit tests.

For further details on the VPlan model see docs/Proposals/VectorizationPlan.rst
and its references.

Authors: Gil Rapaport and Ayal Zaks

Differential Revision: https://reviews.llvm.org/D32871

llvm-svn: 311077
2017-08-17 09:29:59 +00:00
Jakub Kuderski fd5c5c9144 Reapply: [ADCE][Dominators] Teach ADCE to preserve dominators
Summary:
This patch teaches ADCE to preserve both DominatorTrees and PostDominatorTrees.

I didn't notice any performance impact when bootstrapping clang with this patch.

The patch was originally committed in r311039 and reverted in r311049.
This revision fixes the problem with not adding a dependency on the
DominatorTreeWrapperPass for the LegacyPassManager.

Reviewers: dberlin, chandlerc, sanjoy, davide, grosser, brzycki

Reviewed By: davide

Subscribers: grandinj, zhendongsu, llvm-commits, david2050

Differential Revision: https://reviews.llvm.org/D35869

llvm-svn: 311057
2017-08-17 01:41:49 +00:00
Amjad Aboud 86111c6696 [InstCombine] Teach canEvaluateTruncated to handle arithmetic shift (including those with vector splat shift amount)
Differential Revision: https://reviews.llvm.org/D36784

llvm-svn: 311050
2017-08-16 22:42:38 +00:00
Jakub Kuderski cbcffb173c Revert "[ADCE][Dominators] Teach ADCE to preserve dominators"
This reverts commit r311039. The patch caused the
`test/Bindings/OCaml/Output/scalar_opts.ml` to fail.

llvm-svn: 311049
2017-08-16 22:10:53 +00:00
Craig Topper 882f29630b [InstCombine] Make folding (X >s -1) ? C1 : C2 --> ((X >>s 31) & (C2 - C1)) + C1 support splat vectors
This also uses decomposeBitTestICmp to decode the compare.

Differential Revision: https://reviews.llvm.org/D36781

llvm-svn: 311044
2017-08-16 21:52:07 +00:00
Jakub Kuderski 4552e9de9f [ADCE][Dominators] Teach ADCE to preserve dominators
Summary:
This patch teaches ADCE to preserve both DominatorTrees and PostDominatorTrees.

I didn't notice any performance impact when bootstrapping clang with this patch.

Reviewers: dberlin, chandlerc, sanjoy, davide, grosser, brzycki

Reviewed By: davide

Subscribers: grandinj, zhendongsu, llvm-commits, david2050

Differential Revision: https://reviews.llvm.org/D35869

llvm-svn: 311039
2017-08-16 20:50:23 +00:00
Geoff Berry 40549ad1ac [LoopDataPrefetch][AArch64FalkorHWPFFix] Preserve ScalarEvolution
Summary:
Mark LoopDataPrefetch and AArch64FalkorHWPFFix passes as preserving
ScalarEvolution since they do not alter loop structure and should not
alter any SCEV values (though LoopDataPrefetch may introduce new
instructions that won't have cached SCEV values yet).

This can result in slight code differences, mainly w.r.t. nsw/nuw flags
on SCEVs, since these are computed somewhat lazily when a zext/sext
instruction is encountered.  As a result, passes after the modified
passes may see SCEVs with more nsw/nuw flags present.

Reviewers: sanjoy, anemet

Subscribers: aemerson, rengolin, mzolotukhin, javed.absar, kristof.beyls, mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D36716

llvm-svn: 311032
2017-08-16 19:03:16 +00:00
Hal Finkel 9e54b7093a [BDCE] Don't check demanded bits on unsized types
To clear assumptions that are potentially invalid after trivialization, we need
to walk the use/def chain. Normally, the only way to reach an instruction with
an unsized type is via an instruction that has side effects (or otherwise will
demand its input bits). That would stop the walk. However, if we have a
readnone function that returns an unsized type (e.g., void), we must avoid
asking for the demanded bits of the function call's return value. A
void-returning readnone function is always dead (and so we can stop walking the
use/def chain here), but the check is necessary to avoid asserting.

Fixes PR34211.

llvm-svn: 311014
2017-08-16 16:09:22 +00:00
Dehao Chen 84d412035a Merge debug info when hoist then-else code to if.
Summary: When we move then-else code to if, we need to merge its debug info, otherwise the hoisted instruction may have inaccurate debug info attached.

Reviewers: aprantl, probinson, dblaikie, echristo, loladiro

Reviewed By: aprantl

Subscribers: sanjoy, llvm-commits

Differential Revision: https://reviews.llvm.org/D36778

llvm-svn: 310985
2017-08-16 01:55:26 +00:00
Craig Topper 0a1a276d91 [InstCombine] Teach canEvaluateZExtd and canEvaluateTruncated to handle vector shifts with splat shift amount
We were only allowing ConstantInt before. This patch allows splat of ConstantInt too.

Differential Revision: https://reviews.llvm.org/D36763

llvm-svn: 310970
2017-08-15 22:48:41 +00:00
Amjad Aboud 0464c5d958 [InstCombine] Added support for (X >>s C) << C --> X & (-1 << C)
Differential Revision: https://reviews.llvm.org/D36743

llvm-svn: 310949
2017-08-15 19:33:14 +00:00
Sanjay Patel f69b7d5c93 [InstCombine] sink sext after ashr
Narrow ops are better for bit-tracking, and in the case of vectors,
may enable better codegen.

As the trunc test shows, this can allow follow-on simplifications.

There's a block of code in visitTrunc that deals with shifted ops
with FIXME comments. It may be possible to remove some of that now,
but I want to make sure there are no problems with this step first.

http://rise4fun.com/Alive/Y3a

Name: hoist_ashr_ahead_of_sext_1
  %s = sext i8 %x to i32
  %r = ashr i32 %s, 3  ; shift value is < than source bit width
  =>
  %a = ashr i8 %x, 3
  %r = sext i8 %a to i32
  
Name: hoist_ashr_ahead_of_sext_2
  %s = sext i8 %x to i32
  %r = ashr i32 %s, 8  ; shift value is >= than source bit width
  =>
  %a = ashr i8 %x, 7   ; so clamp this shift value
  %r = sext i8 %a to i32
  
Name: junc_the_trunc  
  %a = sext i16 %v to i32
  %s = ashr i32 %a, 18
  %t = trunc i32 %s to i16
  =>
  %t = ashr i16 %v, 15
llvm-svn: 310942
2017-08-15 18:25:52 +00:00
Jakub Kuderski 638c085d07 [Dominators] Include infinite loops in PostDominatorTree
Summary:
This patch teaches PostDominatorTree about infinite loops. It is built on top of D29705 by @dberlin which includes a very detailed motivation for this change.

What's new is that the patch also teaches the incremental updater how to deal with reverse-unreachable regions and how to properly maintain and verify tree roots. Before that, the incremental algorithm sometimes ended up preserving reverse-unreachable regions after updates that wouldn't appear in the tree if it was constructed from scratch on the same CFG.

This patch makes the following assumptions:
- A sequence of updates should produce the same tree as a recalculating it.
- Any sequence of the same updates should lead to the same tree.
- Siblings and roots are unordered.

The last two properties are essential to efficiently perform batch updates in the future.
When it comes to the first one, we can decide later that the consistency between freshly built tree and an updated one doesn't matter match, as there are many correct ways to pick roots in infinite loops, and to relax this assumption. That should enable us to recalculate postdominators less frequently.

This patch is pretty conservative when it comes to incremental updates on reverse-unreachable regions and ends up recalculating the whole tree in many cases. It should be possible to improve the performance in many cases, if we decide that it's important enough.
That being said, my experiments showed that reverse-unreachable are very rare in the IR emitted by clang when bootstrapping  clang. Here are the statistics I collected by analyzing IR between passes and after each removePredecessor call:

```
# functions:  52283
# samples:  337609
# reverse unreachable BBs:  216022
# BBs:  247840796
Percent reverse-unreachable:  0.08716159869015269 %
Max(PercRevUnreachable) in a function:  87.58620689655172 %
# > 25 % samples:  471 ( 0.1395104988314885 % samples )
... in 145 ( 0.27733680163724345 % functions )
```

Most of the reverse-unreachable regions come from invalid IR where it wouldn't be possible to construct a PostDomTree anyway.

I would like to commit this patch in the next week in order to be able to complete the work that depends on it before the end of my internship, so please don't wait long to voice your concerns :).

Reviewers: dberlin, sanjoy, grosser, brzycki, davide, chandlerc, hfinkel

Reviewed By: dberlin

Subscribers: nhaehnle, javed.absar, kparzysz, uabelho, jlebar, hiraditya, llvm-commits, dberlin, david2050

Differential Revision: https://reviews.llvm.org/D35851

llvm-svn: 310940
2017-08-15 18:14:57 +00:00
Rui Ueyama 4a17955030 Fix -Wunused-lambda-capture for Release build.
`I` and `this` are used only in assert or DEBUG, so they are unused
in Release build.

llvm-svn: 310934
2017-08-15 17:39:35 +00:00
Ayal Zaks 25e2800e20 [LV] Minor savings to Sink casts to unravel first order recurrence
Two minor savings: avoid copying the SinkAfter map and avoid moving a cast if it
is not needed.

Differential Revision: https://reviews.llvm.org/D36408

llvm-svn: 310910
2017-08-15 08:32:59 +00:00
Dinar Temirbulatov 9e43d6e7b2 [SLPVectorizer] Replace VL[0] to VL0 with assert, add propagateIRFlags extra parameter VL0,
replace E->Scalars[0] to VL0, NFCI.

llvm-svn: 310904
2017-08-15 00:31:49 +00:00
Dehao Chen 45847d3612 Add missing dependency in ICP. (NFC)
llvm-svn: 310896
2017-08-14 23:25:21 +00:00
Reid Kleckner 18728822d2 Remove checks for debug info intrinsics in use lists, NFC
These haven't done anything since debug info intrinsics stopped
appearing in Value use lists in 2014.

llvm-svn: 310892
2017-08-14 22:10:54 +00:00
Craig Topper 0aa3a19512 Recommit r310869, "[InstSimplify][InstCombine] Modify the interface of decomposeBitTestICmp and use it in the InstSimplify"
This recommits r310869, with the moved files and no extra changes.

Original commit message:

This addresses a fixme in InstSimplify about using decomposeBitTest. This also fixes InstSimplify to handle ugt and ult compares too.

I've modified the interface a little to return only the APInt version of the mask that InstSimplify needs. InstCombine now has a small wrapper routine to create a Constant out of it. I've also dropped the returning of 0 since InstSimplify doesn't need that. So InstCombine creates a zero constant itself.

I also had to make decomposeBitTest support vectors since InstSimplify needs that.

As InstSimplify can't use something from the Transforms library, I've moved the CmpInstAnalysis code to the Analysis library.

Differential Revision: https://reviews.llvm.org/D36593

llvm-svn: 310889
2017-08-14 21:39:51 +00:00
Andrew Kaylor 53a5fbb45f Add strictfp attribute to prevent unwanted optimizations of libm calls
Differential Revision: https://reviews.llvm.org/D34163

llvm-svn: 310885
2017-08-14 21:15:13 +00:00
Craig Topper 69fa8e0d99 Revert r310869 "[InstSimplify][InstCombine] Modify the interface of decomposeBitTestICmp and use it in the InstSimplify"
Failed to add the two files that moved. And then added an extra change I didn't mean to while trying to fix that. Reverting everything.

llvm-svn: 310873
2017-08-14 19:09:32 +00:00
Craig Topper 2f0b450666 [InstSimplify][InstCombine] Modify the interface of decomposeBitTestICmp and use it in the InstSimplify
This addresses a fixme in InstSimplify about using decomposeBitTest. This also fixes InstSimplify to handle ugt and ult compares too.

I've modified the interface a little to return only the APInt version of the mask that InstSimplify needs. InstCombine now has a small wrapper routine to create a Constant out of it. I've also dropped the returning of 0 since InstSimplify doesn't need that. So InstCombine creates a zero constant itself.

I also had to make decomposeBitTest support vectors since InstSimplify needs that.

As InstSimplify can't use something from the Transforms library, I've moved the CmpInstAnalysis code to the Analysis library.

Differential Revision: https://reviews.llvm.org/D36593

llvm-svn: 310869
2017-08-14 18:49:42 +00:00
Dinar Temirbulatov 7b78f5e52d [SLPVectorizer] Schedule bundle with different opcodes.
This change let us schedule a bundle with different opcodes in it, for example : [ load, add, add, add ]

Reviewers: mkuper, RKSimon, ABataev, mzolotukhin, spatel, filcab

Subscribers: llvm-commits, rengolin

Differential Revision: https://reviews.llvm.org/D36518

llvm-svn: 310847
2017-08-14 15:40:16 +00:00
Sanjay Patel a1067d9bae [BDCE] reduce scope of an assert (PR34179)
The assert was added with r310779 and is usually correct,
but as the test shows, not always. The 'volatile' on the
load is needed to expose the faulty path because without
it, DemandedBits would return that the load is just dead
rather than not demanded, and so we wouldn't hit the
bogus assert.

Also, since the lambda is just a single-line now, get rid 
of it and inline the DB.isAllOnesValue() calls. 

This should fix (prevent execution of a faulty assert):
https://bugs.llvm.org/show_bug.cgi?id=34179

llvm-svn: 310842
2017-08-14 15:13:46 +00:00
Sam Parker 718c8a6a2a [LoopUnroll] Enable option to peel remainder loop
On some targets, the penalty of executing runtime unrolling checks
and then not the unrolled loop can be significantly detrimental to
performance. This results in the need to be more conservative with
the unroll count, keeping a trip count of 2 reduces the overhead as
well as increasing the chance of the unrolled body being executed. But
being conservative leaves performance gains on the table.

This patch enables the unrolling of the remainder loop introduced by
runtime unrolling. This can help reduce the overhead of misunrolled
loops because the cost of non-taken branches is much less than the
cost of the backedge that would normally be executed in the remainder
loop. This allows larger unroll factors to be used without suffering
performance loses with smaller iteration counts.

Differential Revision: https://reviews.llvm.org/D36309

llvm-svn: 310824
2017-08-14 09:25:26 +00:00