Commit Graph

7846 Commits

Author SHA1 Message Date
Max Kazantsev 80843a0acc [SCEV][NFC] Factor out common logic into a separate method
SCEV has multiple occurences of code when we need to prove some predicate on
every iteration of a loop and do it with invocations of couple `isLoopEntryGuardedByCond`,
`isLoopBackedgeGuardedByCond`. This patch factors out these two calls into a separate
method. It is a preparation step to extend this logic: it is not the only way how we can prove
such conditions.

Differential Revision: https://reviews.llvm.org/D43373

llvm-svn: 325745
2018-02-22 06:27:32 +00:00
Silviu Baranga 10ad93c6bf [SCEV] Temporarily disable loop versioning for the purpose
of turning SCEVUnknowns of PHIs into AddRecExprs.

This feature is now hidden behind the -scev-version-unknown flag.

Fixes PR36032 and PR35432.

llvm-svn: 325687
2018-02-21 15:20:32 +00:00
Benjamin Kramer fd0630665b [MemoryBuiltins] Check nobuiltin status when identifying calls to free.
This is usually not a problem because this code's main purpose is
eliminating unused new/delete pairs. We got deletes of nullptr or
nobuiltin deletes of builtin new wrong though.

llvm-svn: 325630
2018-02-20 22:00:33 +00:00
Sanjay Patel adf6e88c74 [PatternMatch, InstSimplify] enhance m_AllOnes() to ignore undef elements in vectors
Loosening the matcher definition reveals a subtle bug in InstSimplify (we should not
assume that because an operand constant matches that it's safe to return it as a result).

So I'm making that change here too (that diff could be independent, but I'm not sure how 
to reveal it before the matcher change).

This also seems like a good reason to *not* include matchers that capture the value.
We don't want to encourage the potential misstep of propagating undef values when it's
not allowed/intended.

I didn't include the capture variant option here or in the related rL325437 (m_One), 
but it already exists for other constant matchers.

llvm-svn: 325466
2018-02-18 18:05:08 +00:00
Sanjay Patel ac3952052b [InstSimplify] move select undef cond fold with other constant cond folds; NFCI
llvm-svn: 325434
2018-02-17 14:50:13 +00:00
Brian M. Rzycki f1a7df5ef2 [JumpThreading] PR36133 enable/disable DominatorTree for LVI analysis
Summary:
The LazyValueInfo pass caches a copy of the DominatorTree when available.
Whenever there are pending DominatorTree updates within JumpThreading's
DeferredDominance object we cannot use the cached DT for LVI analysis.
This commit adds the new methods enableDT() and disableDT() to LVI.
JumpThreading also sets the appropriate usage model before calling LVI
analysis methods.

Fixes https://bugs.llvm.org/show_bug.cgi?id=36133

Reviewers: sebpop, dberlin, kuhar

Reviewed by: sebpop, kuhar

Subscribers: uabelho, llvm-commits, aprantl, hiraditya, a.elovikov

Differential Revision: https://reviews.llvm.org/D42717

llvm-svn: 325356
2018-02-16 16:35:17 +00:00
Max Kazantsev fd18002990 [NFC] Rename isKnownViaSimpleReasoning to isKnownViaNonRecursiveReasoning
llvm-svn: 325216
2018-02-15 07:47:17 +00:00
Max Kazantsev c5941d12f4 [SCEV] Favor isKnownViaSimpleReasoning over constant ranges check
There is a more powerful but still simple function `isKnownViaSimpleReasoning ` that
does constant range check and few more additional checks. We use it some places (e.g.
when proving implications) and in some other places we only check constant ranges.

Currently, indvar simplifier fails to remove the check in following loop:

  int inc = ...;
  for (int i = inc, j = inc - 1; i < 200; ++i, ++j)
    if (i > j) { ... }

This patch replaces all usages of `isKnownPredicateViaConstantRanges` with
`isKnownViaSimpleReasoning` to have smarter proofs. In particular, it fixes the
case above.

Reviewed-By: sanjoy
Differential Revision: https://reviews.llvm.org/D43175

llvm-svn: 325214
2018-02-15 07:09:00 +00:00
Elena Demikhovsky 945b7e5aa6 Adding a width of the GEP index to the Data Layout.
Making a width of GEP Index, which is used for address calculation, to be one of the pointer properties in the Data Layout.
p[address space]:size:memory_size:alignment:pref_alignment:index_size_in_bits.
The index size parameter is optional, if not specified, it is equal to the pointer size.

Till now, the InstCombiner normalized GEPs and extended the Index operand to the pointer width.
It works fine if you can convert pointer to integer for address calculation and all registered targets do this.
But some ISAs have very restricted instruction set for the pointer calculation. During discussions were desided to retrieve information for GEP index from the Data Layout.
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120416.html

I added an interface to the Data Layout and I changed the InstCombiner and some other passes to take the Index width into account.
This change does not affect any in-tree target. I added tests to cover data layouts with explicitly specified index size.

Differential Revision: https://reviews.llvm.org/D42123

llvm-svn: 325102
2018-02-14 06:58:08 +00:00
Sanjay Patel 246d769232 [InstSimplify] allow exp/log simplifications with only 'reassoc' FMF
These intrinsic folds were added with D41381, but only allowed with isFast().
That's more than necessary because FMF has 'reassoc' to apply to these
kinds of folds after D39304, and that's all we need in these cases.

Differential Revision: https://reviews.llvm.org/D43160

llvm-svn: 324967
2018-02-12 23:51:23 +00:00
Max Kazantsev db3a9e0cfe [SCEV] Make getPostIncExpr guaranteed to return AddRec
The current implementation of `getPostIncExpr` invokes `getAddExpr` for two recurrencies
and expects that it always returns it a recurrency. But this is not guaranteed to happen if we
have reached max recursion depth or refused to make SCEV simplification for other reasons.

This patch changes its implementation so that now it always returns SCEVAddRec without
relying on `getAddExpr`.

Differential Revision: https://reviews.llvm.org/D42953

llvm-svn: 324866
2018-02-12 05:09:38 +00:00
Sanjay Patel a60aec1ab7 [ValueTracking] don't crash when assumptions conflict (PR36270)
The last assume in the test says that %B12 is 0. 
The first assume says that %and1 is less than %B12. 
Therefore, %and1 is unsigned less than 0...does not compute.

That means this line:
Known.Zero.setHighBits(RHSKnown.countMinLeadingZeros() + 1);
...tries to set more bits than exist.

Differential Revision: https://reviews.llvm.org/D43052

llvm-svn: 324610
2018-02-08 14:52:40 +00:00
Max Kazantsev b299ade2c5 Re-enable "[SCEV] Make isLoopEntryGuardedByCond a bit smarter"
The failures happened because of assert which was overconfident about
SCEV's proving capabilities and is generally not valid.

Differential Revision: https://reviews.llvm.org/D42835

llvm-svn: 324473
2018-02-07 11:16:29 +00:00
Serguei Katkov 69246ca787 Revert [SCEV] Make isLoopEntryGuardedByCond a bit smarter
Revert rL324453 commit which causes buildbot failures.

Differential Revision: https://reviews.llvm.org/D42835

llvm-svn: 324462
2018-02-07 09:10:08 +00:00
Max Kazantsev dd5ee6f5d9 [SCEV] Make isLoopEntryGuardedByCond a bit smarter
Sometimes `isLoopEntryGuardedByCond` cannot prove predicate `a > b` directly.
But it is a common situation when `a >= b` is known from ranges and `a != b` is
known from a dominating condition. Thia patch teaches SCEV to sum these facts
together and prove strict comparison via non-strict one.

Differential Revision: https://reviews.llvm.org/D42835

llvm-svn: 324453
2018-02-07 07:56:26 +00:00
Michael Zolotukhin e82e83fcce Follow-up for r324429: "[LCSSAVerification] Run verification only when asserts are enabled."
Before r324429 we essentially didn't have a verification of LCSSA, so
no wonder that it has been broken: currently loop-sink breaks it (the
attached test illustrates the failure).

It was detected during a stage2 RA build, so to unbreak it I'm disabling
the check for now.

llvm-svn: 324445
2018-02-07 04:24:44 +00:00
Michael Zolotukhin ec8b0ecaab [LCSSAVerification] Run verification only when asserts are enabled.
llvm-svn: 324429
2018-02-07 00:13:08 +00:00
Simon Pilgrim 9f2ae7e2d1 [InstCombine][ValueTracking] Match non-uniform constant power-of-two vectors
Generalize existing constant matching to work with non-uniform constant vectors as well.

Differential Revision: https://reviews.llvm.org/D42818

llvm-svn: 324369
2018-02-06 18:39:23 +00:00
Sanjay Patel d7c702b451 [LoopStrengthReduce, x86] don't add cost for a cmp that will be macro-fused (PR35681)
In the motivating case from PR35681 and represented by the macro-fuse-cmp test:
https://bugs.llvm.org/show_bug.cgi?id=35681
...there's a 37 -> 31 byte size win for the loop because we eliminate the big base 
address offsets.

SPEC2017 on Ryzen shows no significant perf difference.

Differential Revision: https://reviews.llvm.org/D42607

llvm-svn: 324289
2018-02-05 23:43:05 +00:00
Serguei Katkov ec7029c286 Re-apply [SCEV] Fix isLoopEntryGuardedByCond usage
ScalarEvolution::isKnownPredicate invokes isLoopEntryGuardedByCond without check
that SCEV is available at entry point of the loop. It is incorrect and fixed by patch.

To bugs additionally fixed:
assert is moved after the check whether loop is not a nullptr.
Usage of isLoopEntryGuardedByCond in ScalarEvolution::isImpliedCondOperandsViaNoOverflow
is guarded by isAvailableAtLoopEntry.

Reviewers: sanjoy, mkazantsev, anna, dorit, reames
Reviewed By: mkazantsev
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42417

llvm-svn: 324204
2018-02-05 05:49:47 +00:00
Ivan A. Kosarev ab68bbe515 [Analysis] Support aggregate access types in TBAA
This patch implements analysis for new-format TBAA access tags
with aggregate types as their final access types.

Differential Revision: https://reviews.llvm.org/D41501

llvm-svn: 324092
2018-02-02 14:09:22 +00:00
Easwaran Raman 06a715333a Remove CallGraphTraits and use equivalent methods in GraphTraits
Summary:
D42698 adds child_edge_{begin|end} and children_edges to GraphTraits
which are used here. The reason for this change is to make it easy to
use count propagation on ModulesummaryIndex. As it stands,
CallGraphTraits is in Analysis while ModuleSummaryIndex is in IR.

Reviewers: davidxl, dberlin

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42703

llvm-svn: 323994
2018-02-01 19:40:35 +00:00
Chih-Hung Hsieh 60d1e79ffb [Analysis] Disable calls to *_finite and other glibc-only functions on Android.
Since r322087, glibc's finite lib calls are generated when possible.
However, they are not supported on Android. This change also
disables other functions not available on Android.

Differential Revision: http://reviews.llvm.org/D42668

llvm-svn: 323898
2018-01-31 19:12:50 +00:00
Daniel Neilson 147810d28a [Lint] Upgrade uses of MemoryIntrinic::getAlignment() to new API. (NFCI)
Summary:
  This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the Lint
analysis to cease using the old getAlignment() API of MemoryIntrinsic in favour of getting
source & dest specific alignments through the new API.

Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead.
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.

Reference
   http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.html
   http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

llvm-svn: 323886
2018-01-31 16:42:15 +00:00
Zaara Syeda 1f59ae311b Re-commit : [PowerPC] Add handling for ColdCC calling convention and a pass to mark
candidates with coldcc attribute.

This recommits r322721 reverted due to sanitizer memory leak build bot failures.

Original commit message:
This patch adds support for the coldcc calling convention for Power.
This changes the set of non-volatile registers. It includes a pass to stress
test the implementation by marking all static directly called functions with
the coldcc attribute through the option -enable-coldcc-stress-test. It also
includes an option, -ppc-enable-coldcc, to add the coldcc attribute to
functions which are cold at all call sites based on BlockFrequencyInfo when
the containing function does not call any non cold functions.

Differential Revision: https://reviews.llvm.org/D38413

llvm-svn: 323778
2018-01-30 16:17:22 +00:00
Sanjay Patel 83f056604c [InstSimplify] (X * Y) / Y --> X for relaxed floating-point ops
This is the FP counterpart that was mentioned in PR35709:
https://bugs.llvm.org/show_bug.cgi?id=35709

Differential Revision: https://reviews.llvm.org/D42385

llvm-svn: 323716
2018-01-30 00:18:37 +00:00
Florian Hahn 1636651e35 [InlineCost] Mark functions accessing varargs as not viable.
This prevents functions accessing varargs from being inlined if they
have the alwaysinline attribute.

Reviewers: efriedma, rnk, davide

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D42556

llvm-svn: 323619
2018-01-28 19:11:49 +00:00
Easwaran Raman 8410c37465 [SyntheticCounts] Rewrite the code using only graph traits.
Summary:
The intent of this is to allow the code to be used with ThinLTO. In
Thinlink phase, a traditional Callgraph can not be computed even though
all the necessary information (nodes and edges of a call graph) is
available. This is due to the fact that CallGraph class is closely tied
to the IR. This patch first extends GraphTraits to add a CallGraphTraits
graph. This is then used to implement a version of counts propagation
on a generic callgraph.

Reviewers: davidxl

Subscribers: mehdi_amini, tejohnson, llvm-commits

Differential Revision: https://reviews.llvm.org/D42311

llvm-svn: 323475
2018-01-25 22:02:29 +00:00
Easwaran Raman c73cec84c9 Re-land "[ThinLTO] Add call edges' relative block frequency to per-module summary."
It was reverted after buildbot regressions.

Original commit message:

This allows relative block frequency of call edges to be passed
to the thinlink stage where it will be used to compute synthetic
entry counts of functions.

llvm-svn: 323460
2018-01-25 19:27:17 +00:00
Easwaran Raman bf38deef3f Revert "[ThinLTO] Add call edges' relative block frequency to per-module summary."
Causes buildbot regressions.

llvm-svn: 323358
2018-01-24 18:15:29 +00:00
Easwaran Raman 5f7aff9a0a [ThinLTO] Add call edges' relative block frequency to per-module summary.
Summary:
This allows relative block frequency of call edges to be passed to the
thinlink stage where it will be used to compute synthetic entry counts
of functions.

Reviewers: tejohnson, pcc

Subscribers: mehdi_amini, llvm-commits, inglorion

Differential Revision: https://reviews.llvm.org/D42212

llvm-svn: 323349
2018-01-24 17:51:23 +00:00
Zvi Rackover 51f0d64b9c InstSimplify: If divisor element is undef simplify to undef
Summary:
If any vector divisor element is undef, we can arbitrarily choose it be
zero which would make the div/rem an undef value by definition.

Reviewers: spatel, reames

Reviewed By: spatel

Subscribers: magabari, llvm-commits

Differential Revision: https://reviews.llvm.org/D42485

llvm-svn: 323343
2018-01-24 17:22:00 +00:00
Sanjay Patel 1d91ec34b2 [ValueTracking] add recursion depth param to matchSelectPattern
We're getting bug reports:
https://bugs.llvm.org/show_bug.cgi?id=35807
https://bugs.llvm.org/show_bug.cgi?id=35840
https://bugs.llvm.org/show_bug.cgi?id=36045
...where we blow up the stack in value tracking because other passes are sending 
in selects that have an operand that is itself the select.

We don't currently have a reliable way to avoid analyzing dead code that may take 
non-standard forms, so bail out when things go too far.

This mimics the recursion depth limitations in other parts of value tracking.

Unfortunately, this pushes the underlying problems for other passes (jump-threading,
simplifycfg, correlated-propagation) into hiding. If someone wants to uncover those
again, the first draft of this patch on Phab would do that (it would assert rather
than bail out).

Differential Revision: https://reviews.llvm.org/D42442

llvm-svn: 323331
2018-01-24 15:20:37 +00:00
Malcolm Parsons 21e545d08d Fix typos of occurred and occurrence
llvm-svn: 323318
2018-01-24 10:33:39 +00:00
MinSeong Kim 27f77b4300 [Analysis] Disable exp/exp2/pow finite lib calls on Android with -ffast-math.
Summary:
Since r322087, glibc's finite lib calls are generated when possible.
However, glibc is not supported on Android. Therefore this change
enables llvm to finely distinguish between linux and Android for
unsupported library calls. The change also include some regression
tests.

Reviewers: srhines, pirama

Reviewed By: srhines

Subscribers: kongyi, chh, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D42288

llvm-svn: 323187
2018-01-23 11:11:36 +00:00
Anton Bikineev 82f61151b3 [InstSimplify] (X << Y) % X -> 0
llvm-svn: 323182
2018-01-23 09:27:47 +00:00
Eugene Leviant 28d8a49f42 [ThinLTO] Re-commit of dot dumper after test fix
llvm-svn: 323116
2018-01-22 13:35:40 +00:00
Serguei Katkov f38041dc3e Revert [SCEV] Fix isLoopEntryGuardedByCond usage
It causes buildbot failures. New added assert is fired.
It seems not all usages of isLoopEntryGuardedByCond are fixed.

llvm-svn: 323079
2018-01-22 07:47:02 +00:00
Serguei Katkov 50714a1cbc [SCEV] Fix isLoopEntryGuardedByCond usage
ScalarEvolution::isKnownPredicate invokes isLoopEntryGuardedByCond without check
that SCEV is available at entry point of the loop. It is incorrect and fixed by patch.

Reviewers: sanjoy, mkazantsev, anna, dorit
Reviewed By: mkazantsev
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42165

llvm-svn: 323077
2018-01-22 07:31:41 +00:00
Eugene Leviant 72b9bdb71a Temporarily revert r323062 to investigate buildbot failures
llvm-svn: 323065
2018-01-21 10:22:19 +00:00
Eugene Leviant 453c976a63 [ThinLTO] Implement summary visualizer
Differential revision: https://reviews.llvm.org/D41297

llvm-svn: 323062
2018-01-21 07:27:32 +00:00
Sanjay Patel 33cb84571f [InstSimplify] use m_Specific and commutative matcher to reduce code; NFCI
llvm-svn: 322955
2018-01-19 16:12:55 +00:00
Alina Sbirlea df26cf8117 [ModRefInfo] Return NoModRef for Must and NoModRef.
Summary:
In ModRefInfo "Must" was introduced to track presence of MustAlias, but we still want to return NoModRef when there is neither Mod or Ref, even when MustAlias is found. Patch has small fixes to ensure this happens.
Minor cleanup to remove nesting for 2 if statements when calling getModRefInfo for 2 ImmutableCallSites.

Reviewers: sanjoy

Subscribers: jlebar, llvm-commits

Differential Revision: https://reviews.llvm.org/D42209

llvm-svn: 322932
2018-01-19 10:26:40 +00:00
Easwaran Raman e5b8de2f1f Add a ProfileCount class to represent entry counts.
Summary:
The class wraps a uint64_t and an enum to represent the type of profile
count (real and synthetic) with some helper methods.

Reviewers: davidxl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41883

llvm-svn: 322771
2018-01-17 22:24:23 +00:00
Zaara Syeda c9dc7b451b Revert [PowerPC] This reverts commit rL322721
Failing build bots. Revert the commit now.

llvm-svn: 322748
2018-01-17 20:00:15 +00:00
Philip Reames f5ff5d584e [MDA] Use common code instead of reimplementing same. [NFC]
llvm-svn: 322747
2018-01-17 19:57:19 +00:00
Zaara Syeda 8e951fd2f6 [PowerPC] Add handling for ColdCC calling convention and a pass to mark
candidates with coldcc attribute.

This patch adds support for the coldcc calling convention for Power.
This changes the set of non-volatile registers. It includes a pass to stress
test the implementation by marking all static directly called functions with
the coldcc attribute through the option -enable-coldcc-stress-test. It also
includes an option, -ppc-enable-coldcc, to add the coldcc attribute to
functions which are cold at all call sites based on BlockFrequencyInfo when
the containing function does not call any non cold functions.

Differential Revision: https://reviews.llvm.org/D38413

llvm-svn: 322721
2018-01-17 18:22:55 +00:00
Hiroshi Inoue 8f976ba0bf [NFC] fix trivial typos in comments
"the the" -> "the"

llvm-svn: 322636
2018-01-17 12:29:38 +00:00
Mikael Holmen 4653b1a4f1 [GlobalsAA] Don't let dbg intrinsics affect analysis result
Summary:
This fixes PR35899.

Debug info intrinsics shouldn't affect code generation so ignore them
in GlobalsAA.

Reviewers: hfinkel, aprantl

Reviewed By: aprantl

Subscribers: aprantl, llvm-commits

Differential Revision: https://reviews.llvm.org/D41984

llvm-svn: 322470
2018-01-15 07:05:51 +00:00
Davide Italiano 7ccd4619e4 [BasicAA] Stop crashing when dealing with pointers > 64 bits.
An alternative (and probably better) fix would be that of
making `Scale` an APInt, and there's a patch floating around
to do this. As we're still discussing it, at least stop crashing
in the meanwhile (added bonus, we now have a regression test for
this situation).

Fixes PR35843.

Thanks to Eli for suggesting the fix and Simon for reporting and
reducing the bug.

llvm-svn: 322467
2018-01-15 01:40:18 +00:00
Sanjay Patel 9568f42a7a [InstSimplify] fix code comments; NFC
llvm-svn: 322456
2018-01-14 15:58:18 +00:00
Sanjay Patel 4158eff0f8 [InstSimplify] fold implied null ptr check (PR35790)
This extends rL322327 to handle the pointer cast and should solve:
https://bugs.llvm.org/show_bug.cgi?id=35790

Name: or_eq_zero
  %isnull = icmp eq i64* %p, null
  %x = ptrtoint i64* %p to i64
  %somebits = and i64 %x, %y
  %somebits_are_zero = icmp eq i64 %somebits, 0
  %or = or i1 %somebits_are_zero, %isnull
  =>
  %or = %somebits_are_zero

Name: and_ne_zero
  %isnotnull = icmp ne i64* %p, null
  %x = ptrtoint i64* %p to i64
  %somebits = and i64 %x, %y
  %somebits_are_not_zero = icmp ne i64 %somebits, 0
  %and = and i1 %somebits_are_not_zero, %isnotnull
  =>
  %and = %somebits_are_not_zero

https://rise4fun.com/Alive/CQ3

llvm-svn: 322439
2018-01-13 15:44:44 +00:00
Sanjay Patel 6ef6aa987c [InstSimplify] fold implied cmp with zero (PR35790)
This doesn't handle the more complicated case in the bug report yet:
https://bugs.llvm.org/show_bug.cgi?id=35790

For that, we have to match / look through a cast.

llvm-svn: 322327
2018-01-11 23:27:37 +00:00
Sanjay Patel e63d8dda5a [ValueTracking] recognize min/max-of-min/max with notted ops (PR35875)
This was originally planned as the fix for:
https://bugs.llvm.org/show_bug.cgi?id=35834
...but simpler transforms handled that case, so I implemented a 
lesser solution. It turns out we need to handle the case with 'not'
ops too because the real code example that we are trying to solve:
https://bugs.llvm.org/show_bug.cgi?id=35875
...has extra uses of the intermediate values, so we can't rely on 
smaller canonicalizations to get us to the goal.

As with rL321672, I've tried to show every possibility in the
codegen tests because that's the simplest way to prove we're doing
the right thing in the wide variety of permutations of this pattern.

We can also show an InstCombine win because we added a fold for
this case in:
rL321998 / D41603

An Alive proof for one variant of the pattern to show that the 
InstCombine and codegen results are correct:
https://rise4fun.com/Alive/vd1

Name: min3_nots
  %nx = xor i8 %x, -1
  %ny = xor i8 %y, -1
  %nz = xor i8 %z, -1
  %cmpxz = icmp slt i8 %nx, %nz
  %minxz = select i1 %cmpxz, i8 %nx, i8 %nz
  %cmpyz = icmp slt i8 %ny, %nz
  %minyz = select i1 %cmpyz, i8 %ny, i8 %nz
  %cmpyx = icmp slt i8 %y, %x
  %r = select i1 %cmpyx, i8 %minxz, i8 %minyz
=>
  %cmpxyz = icmp slt i8 %minxz, %ny
  %r = select i1 %cmpxyz, i8 %minxz, i8 %ny

Name: min3_nots_alt
  %nx = xor i8 %x, -1
  %ny = xor i8 %y, -1
  %nz = xor i8 %z, -1
  %cmpxz = icmp slt i8 %nx, %nz
  %minxz = select i1 %cmpxz, i8 %nx, i8 %nz
  %cmpyz = icmp slt i8 %ny, %nz
  %minyz = select i1 %cmpyz, i8 %ny, i8 %nz
  %cmpyx = icmp slt i8 %y, %x
  %r = select i1 %cmpyx, i8 %minxz, i8 %minyz
=>
  %xz = icmp sgt i8 %x, %z
  %maxxz = select i1 %xz, i8 %x, i8 %z
  %xyz = icmp sgt i8 %maxxz, %y
  %maxxyz = select i1 %xyz, i8 %maxxz, i8 %y
  %r = xor i8 %maxxyz, -1

llvm-svn: 322283
2018-01-11 15:13:47 +00:00
Bjorn Pettersson 3851496e6e Avoid inlining if there is byval arguments with non-alloca address space
Summary:
After teaching InlineCost more about address spaces ()
another fault was detected in the inliner. If an argument has
the byval attribute the parameter might be copied to an alloca.
That part seems to work fine even if the argument has a different
address space than the alloca address space. However, if the
address spaces differ, then the inlined function still might
refer to the parameter using the original address space (the
inliner does not handle that situation very well).

This patch avoids the problem by simply disallowing inlining
when there are byval arguments with address space that differs
from the alloca address space.

I'm not really sure how to transform the code if we want to
get inlining for this situation. I assume that it never has
been working, and that the fixes in r321809 just exposed an
old problem.

Fault found by skatkov (Serguei Katkov). It is mentioned in
follow up comments to https://reviews.llvm.org/D40455.

Reviewers: skatkov

Reviewed By: skatkov

Subscribers: uabelho, eraman, llvm-commits, haicheng

Differential Revision: https://reviews.llvm.org/D41898

llvm-svn: 322181
2018-01-10 13:01:18 +00:00
Easwaran Raman bdf20261d8 Add a pass to generate synthetic function entry counts.
Summary:
This pass synthesizes function entry counts by traversing the callgraph
and using the relative block frequencies of the callsites. The intended
use of these counts is in inlining to determine hot/cold callsites in
the absence of profile information.

The pass is split into two files with the code that propagates the
counts in a callgraph in a Utils file. I plan to add support for
propagation in the thinlto link phase and the propagation code will be
shared and hence this split. I did not add support to the old PM since
hot callsite determination in inlining is not possible in old PM
(although we could use hot callee heuristic with synthetic counts in the
old PM it is not worth the effort tuning it)

Reviewers: davidxl, silvas

Subscribers: mgorny, mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D41604

llvm-svn: 322110
2018-01-09 19:39:35 +00:00
Serguei Katkov 6a7a4c6a55 [SCEV] Do not cache S -> V if S is not equivalent of V
SCEV tracks the correspondence of created SCEV to original instruction.
However during creation of SCEV it is possible that nuw/nsw/exact flags are
lost.

As a result during expansion of the SCEV the instruction with nuw/nsw/exact
will be used where it was expected and we produce poison incorreclty.

Reviewers: sanjoy, mkazantsev, sebpop, jbhateja
Reviewed By: sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41578

llvm-svn: 322058
2018-01-09 06:47:14 +00:00
Sanjay Patel 7dfe96ad16 [ValueTracking] remove overzealous assert
The test is derived from a failing fuzz test:
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=5008

Credit to @rksimon for pointing out the problem.

llvm-svn: 322016
2018-01-08 18:31:13 +00:00
Sanjay Patel 52149f0305 [TargetLibraryInfo] fix finite mathlib function availability
This patch was part of:
https://reviews.llvm.org/D41338
...but we can expose the bug in IR via constant propagation
as shown in the test. Unless the triple includes 'linux', we
should not fold these because the functions don't exist on
other platforms (yet?).

llvm-svn: 322010
2018-01-08 17:38:09 +00:00
Florian Hahn 80788d8088 [InlineFunction] Inline vararg functions that do not access varargs.
If the varargs are not accessed by a function, we can inline the
function.

Reviewers: dblaikie, chandlerc, davide, efriedma, rnk, hfinkel

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D41335

llvm-svn: 321940
2018-01-06 19:45:40 +00:00
Davide Italiano 554f68be44 [BasicAA] Fix linearization of shifts beyond the bitwidth.
Thanks to Simon Pilgrim for the reduced testcase.
Fixes PR35821.

llvm-svn: 321873
2018-01-05 16:18:47 +00:00
Bjorn Pettersson 77f3299415 Teach InlineCost about address spaces
Summary:
I basically copied this patch from here:
  https://reviews.llvm.org/D1251
But I skipped some of the refactoring to make the patch more clean.

The new outer3/inner3 test case in ptr-diff.ll triggers the
following assert without this patch:
lib/IR/Constants.cpp:1834: static llvm::Constant *llvm::ConstantExpr::getCompare(unsigned short, llvm::Constant *, llvm::Constant *, bool): Assertion `C1->getType() == C2->getType() && "Op types should be identical!"' failed.

The other new test cases makes sure that there is code coverage
for all modifications in InlineCost.cpp (getting different values
due to not fetching sizes for address space zero). I only guarantee
code coverage for those tests. The tests are not written in a way
that they would break if not having the corrections in
InlineCost.cpp. I found it quite hard to fine tune the tests into
getting different results based on the pointer sizes (except for
the test case where we hit an assert if not teaching InlineCost
about address spaces).

Reviewers: chandlerc, arsenm, haicheng

Reviewed By: arsenm

Subscribers: wdng, eraman, llvm-commits, haicheng

Differential Revision: https://reviews.llvm.org/D40455

llvm-svn: 321809
2018-01-04 18:23:40 +00:00
Dmitry Venikov 3d8cd34a5d [InstSimplify] Missed optimization in math expression: squashing exp(log), log(exp)
Summary: This patch enables folding following expressions under -ffast-math flag: exp(log(x)) -> x, exp2(log2(x)) -> x, log(exp(x)) -> x, log2(exp2(x)) -> x

Reviewers: spatel, hfinkel, davide

Reviewed By: spatel, hfinkel, davide

Subscribers: scanon, llvm-commits

Differential Revision: https://reviews.llvm.org/D41381

llvm-svn: 321710
2018-01-03 14:37:42 +00:00
Sanjay Patel 7811430588 [ValueTracking] recognize min/max of min/max patterns
This is part of solving PR35717:
https://bugs.llvm.org/show_bug.cgi?id=35717

The larger IR optimization is proposed in D41603, but we can show 
the improvement in ValueTracking using codegen tests because 
SelectionDAG creates min/max nodes based on ValueTracking. 

Any target with min/max ops should show wins here. I chose AArch64
vector ops because they're clean and uniform.

Some Alive proofs for the tests (can't put more than 2 tests in 1 
page currently because the web app says it's too long):
https://rise4fun.com/Alive/WRN
https://rise4fun.com/Alive/iPm
https://rise4fun.com/Alive/HmY
https://rise4fun.com/Alive/CNm
https://rise4fun.com/Alive/LYf

llvm-svn: 321672
2018-01-02 20:56:45 +00:00
Dmitry Venikov d2257be8b7 Test commit
Reviewers: Quolyk

Reviewed By: Quolyk

Differential Revision: https://reviews.llvm.org/D41561

llvm-svn: 321636
2018-01-02 05:47:42 +00:00
Simon Pilgrim 6720726d27 [ValueTracking] Don't assume shift values are in range
Reduced (as best I could...) from oss-fuzz #4857 test case

llvm-svn: 321634
2018-01-01 22:44:59 +00:00
Benjamin Kramer c7fc81e659 Use phi ranges to simplify code. No functionality change intended.
llvm-svn: 321585
2017-12-30 15:27:33 +00:00
Philip Reames e499bc3042 [instsimplify] consistently handle undef and out of bound indices for insertelement and extractelement
In one case, we were handling out of bounds, but not undef indices.  In the other, we were handling undef (with the comment making the analogy to out of bounds), but not out of bounds.  Be consistent and treat both undef and constant out of bounds indices as producing undefined results.

As a side effect, this also protects instcombine from having to handle large constant indices as we always simplify first.

llvm-svn: 321575
2017-12-30 05:54:22 +00:00
Max Kazantsev 2c2b1f6d04 [SCEV] Missing depth propagation in recursive call
llvm-svn: 321550
2017-12-29 08:44:32 +00:00
Guozhi Wei 29697c13bc Revert r321377, it causes regression to https://reviews.llvm.org/P8055.
llvm-svn: 321528
2017-12-28 17:02:34 +00:00
Benjamin Kramer 3a13ed60ba Avoid int to string conversion in Twine or raw_ostream contexts.
Some output changes from uppercase hex to lowercase hex, no other functionality change intended.

llvm-svn: 321526
2017-12-28 16:58:54 +00:00
Reid Kleckner 6d31001cd6 Revert "[memcpyopt] Teach memcpyopt to optimize across basic blocks"
This reverts r321138. It seems there are still underlying issues with
memdep. PR35519 seems to still be present if debug info is enabled. We
end up losing a memcpy. Somehow during store to memset merging, we
insert the memset after the memcpy or fail to update the memdep analysis
to account for the newly inserted memset of a pair.

Reduced test case:

  #include <assert.h>
  #include <stdio.h>
  #include <string>
  #include <utility>
  #include <vector>

  void do_push_back(
      std::vector<std::pair<std::string, std::vector<std::string>>>* crls) {
    crls->push_back(std::make_pair(std::string(), std::vector<std::string>()));
  }

  int __attribute__((optnone)) main() {
    // Put some data in the vector and then remove it so we take the push_back
    // fast path.
    std::vector<std::pair<std::string, std::vector<std::string>>> crl_set;
    crl_set.push_back({"asdf", {}});
    crl_set.pop_back();
    printf("first word in vector storage: %p\n", *(void**)crl_set.data());

    // Do the push_back which may fail to initialize the data.
    do_push_back(&crl_set);
    auto* first = &crl_set.back().first;
    printf("first word in vector storage (should be zero): %p\n",
           *(void**)crl_set.data());
    assert(first->empty());
    puts("ok");
  }

Compile with libc++, enable optimizations, and enable debug info:
$ clang++ -stdlib=libc++ -g -O2 t.cpp -o t.exe -Wl,-rpath=llvm/build/lib

This program will assert with this change.

llvm-svn: 321510
2017-12-28 05:10:33 +00:00
Mikael Holmen fb2fd20f50 [Lint] Don't warn about noalias argument aliasing if other argument is byval
Summary:
When using byval, the data is effectively copied as part of the call
anyway, so we aren't actually passing the pointer and thus there is no
reason to issue a warning.

Reviewers: rnk

Reviewed By: rnk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D40118

llvm-svn: 321478
2017-12-27 08:48:33 +00:00
Serguei Katkov da56a7f388 [SCEV] Be careful with nuw/nsw/exact in InsertBinop
InsertBinop tries to find an appropriate instruction instead of
creating a new instruction. When it checks whether instruction is
the same as we need to create it ignores nuw/nsw/exact flags.

It leads to invalid behavior when poison instruction can be used
when it was not expected. Specifically, for example Expander
expands the SCEV built for instruction
%a = add i32 %v, 1
It is possible that InsertBinop can find an instruction
% b = add nuw nsw i32 %v, 1
and will use it instead of version w/o nuw nsw.
It is incorrect.

The patch conservatively ignores all instructions with any of
poison flags installed.

Reviewers: sanjoy, mkazantsev, sebpop, jbhateja
Reviewed By: sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41576

llvm-svn: 321475
2017-12-27 08:26:22 +00:00
Serguei Katkov edf3c8292b [SCEV] Do not insert if it is already in cache
This is fix for the crash caused by ScalarEvolution::getTruncateExpr.

It expects that if it checked the condition that SCEV is not in UniqueSCEVs cache in
the beginning that it will not be there inside this method.

However during recursion and transformation/simplification for sub expression,
it is possible that these modifications will end up with the same SCEV as we started from.

So we must always check whether SCEV is in cache and do not insert item if it is already there.

Reviewers: sanjoy, mkazantsev, craig.topper	
Reviewed By: sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41380

llvm-svn: 321472
2017-12-27 07:15:23 +00:00
Philip Reames 5000ba69d7 Sink a couple of transforms from instcombine into instsimplify.
llvm-svn: 321467
2017-12-27 01:14:30 +00:00
Philip Reames 7a6db4fc4f [NFC] Extract out a helper function for SimplifyCall(CS, Q)
This simplifies code, but the real motivation is that it lets me clean up some downstream code.

llvm-svn: 321466
2017-12-27 00:16:12 +00:00
Sanjay Patel 9a39979dd2 [ValueTracking] ignore FP signed-zero when detecting a casted-to-integer fmin/fmax pattern
This is a preliminary step for the patch discussed in D41136 (and denoted here with the FIXME comment).

When we match an FP min/max that is cast to integer, any intermediate difference between +0.0 or -0.0 
should be muted in the result by the conversion (either fptosi or fptoui) of the result. Thus, we can 
enable 'nsz' for the purpose of matching fmin/fmax.

Note that there's probably room to generalize this more, possibly by fixing the current calls to the
weak version of isKnownNonZero() in matchSelectPattern() to the more powerful recursive version.

Differential Revision: https://reviews.llvm.org/D41333

llvm-svn: 321456
2017-12-26 15:09:19 +00:00
Simon Pilgrim 79c2c2f08c [InstSimplify] Check for in range extraction index before calling APInt::getZExtValue()
Reduced from oss-fuzz #4768 test case

llvm-svn: 321454
2017-12-26 11:42:39 +00:00
Eugene Leviant 193e701d86 [ThinLTO] Don't import functions with noinline attribute
Differential revision: https://reviews.llvm.org/D41489

llvm-svn: 321443
2017-12-25 13:57:24 +00:00
Alina Sbirlea ca741a87f2 [MemorySSA] Allow reordering of loads that alias in the presence of volatile loads.
Summary:
Make MemorySSA allow reordering of two loads that may alias, when one is volatile.
This makes MemorySSA less conservative and behaving the same as the AliasSetTracker.
For more context, see D16875.

LLVM language reference: "The optimizers must not change the number of volatile operations or change their order of execution relative to other volatile operations. The optimizers may change the order of volatile operations relative to non-volatile operations. This is not Java’s “volatile” and has no cross-thread synchronization behavior."

Reviewers: george.burgess.iv, dberlin

Subscribers: sanjoy, reames, hfinkel, llvm-commits, Prazek

Differential Revision: https://reviews.llvm.org/D41525

llvm-svn: 321382
2017-12-22 19:54:03 +00:00
Guozhi Wei 33250340f4 [SimplifyCFG] Don't do if-conversion if there is a long dependence chain
If after if-conversion, most of the instructions in this new BB construct a long and slow dependence chain, it may be slower than cmp/branch, even if the branch has a high miss rate, because the control dependence is transformed into data dependence, and control dependence can be speculated, and thus, the second part can execute in parallel with the first part on modern OOO processor.

This patch checks for the long dependence chain, and give up if-conversion if find one.

Differential Revision: https://reviews.llvm.org/D39352

llvm-svn: 321377
2017-12-22 18:54:04 +00:00
Haicheng Wu 6d14dfe8f3 [InlineCost] Find more free binary operations
Currently, inline cost model considers a binary operator as free only if both
its operands are constants. Some simple cases are missing such as a + 0, a - a,
etc. This patch modifies visitBinaryOperator() to call SimplifyBinOp() without
going through simplifyInstruction() to get rid of the constant restriction.
Thus, visitAnd() and visitOr() are not needed.

Differential Revision: https://reviews.llvm.org/D41494

llvm-svn: 321366
2017-12-22 17:09:09 +00:00
Eli Friedman 39ed9a602b [Inliner] Restrict soft-float inlining penalty.
The penalty is currently getting applied in a bunch of places where it
doesn't make sense, like bitcasts (which are free) and calls (which
were getting the call penalty applied twice). Instead, just apply the
penalty to binary operators and floating-point casts.

While I'm here, also fix getFPOpCost() to do the right thing in more
cases, so we don't have to dig into function attributes.

Differential Revision: https://reviews.llvm.org/D41522

llvm-svn: 321332
2017-12-22 02:08:08 +00:00
Easwaran Raman a17f220590 Add hasProfileData() to check if a function has profile data. NFC.
Summary:
This replaces calls to getEntryCount().hasValue() with hasProfileData
that does the same thing. This refactoring is useful to do before adding
synthetic function entry counts but also a useful cleanup IMO even
otherwise. I have used hasProfileData instead of hasRealProfileData as
David had earlier suggested since I think profile implies "real" and I
use the phrase "synthetic entry count" and not "synthetic profile count"
but I am fine calling it hasRealProfileData if you prefer.

Reviewers: davidxl, silvas

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41461

llvm-svn: 321331
2017-12-22 01:33:52 +00:00
Alina Sbirlea 50db8a2086 [ModRefInfo] Add must alias info to ModRefInfo.
Summary:
Add an additional bit to ModRefInfo, ModRefInfo::Must, to be cleared for known must aliases.
Shift existing Mod/Ref/ModRef values to include an additional most
significant bit. Update wrappers that modify ModRefInfo values to
reflect the change.

Notes:
* ModRefInfo::Must is almost entirely cleared in the AAResults methods, the remaining changes are trying to preserve it.
* Only some small changes to make custom AA passes set ModRefInfo::Must (BasicAA).
* GlobalsModRef already declares a bit, who's meaning overlaps with the most significant bit in ModRefInfo (MayReadAnyGlobal). No changes to shift the value of MayReadAnyGlobal (see AlignedMap). FunctionInfo.getModRef() ajusts most significant bit so correctness is preserved, but the Must info is lost.
* There are cases where the ModRefInfo::Must is not set, e.g. 2 calls that only read will return ModRefInfo::NoModRef, though they may read from exactly the same location.

Reviewers: dberlin, hfinkel, george.burgess.iv

Subscribers: llvm-commits, sanjoy

Differential Revision: https://reviews.llvm.org/D38862

llvm-svn: 321309
2017-12-21 21:41:53 +00:00
Teresa Johnson a4ce3bfdda [PGO] Function section hotness prefix should look at all blocks
Summary:
The function section prefix for PGO based layout (e.g. hot/unlikely)
should look at the hotness of all blocks not just the entry BB.
A function with a cold entry but a very hot loop should be placed in the
hot section, for example, so that it is located close to other hot
functions it may call. For SamplePGO it was already looking at the
branch weights on calls, and I made that code conditional on whether
this is SamplePGO since it was essentially a noop for instrumentation
PGO anyway.

Reviewers: davidxl

Subscribers: eraman, llvm-commits

Differential Revision: https://reviews.llvm.org/D41395

llvm-svn: 321197
2017-12-20 17:53:10 +00:00
Mohammad Shahid 3a934d6ab9 Revert r320548:[SLP] Vectorize jumbled memory loads
llvm-svn: 321181
2017-12-20 15:26:59 +00:00
Dan Gohman aa3922819e [memcpyopt] Teach memcpyopt to optimize across basic blocks
This teaches memcpyopt to make a non-local memdep query when a local query
indicates that the dependency is non-local. This notably allows it to
eliminate many more llvm.memcpy calls in common Rust code, often by 20-30%.

This is r319482 and r319483, along with fixes for PR35519: fix the 
optimization that merges stores into memsets to preserve cached memdep
info, and fix memdep's non-local caching strategy to not assume that larger
queries are always more conservative than smaller ones.

Fixes PR28958 and PR35519.

Differential Revision: https://reviews.llvm.org/D40802

llvm-svn: 321138
2017-12-20 01:36:25 +00:00
Adrian Prantl 0e6694d111 Silence a bunch of implicit fallthrough warnings
llvm-svn: 321114
2017-12-19 22:05:25 +00:00
Francis Visoiu Mistrih 348a4208e3 [CFGVPrinter] Fix -dot-cfg-only
The refactoring in r281640 made -dot-cfg-only ignore the "-only" part.

llvm-svn: 321079
2017-12-19 15:20:18 +00:00
Haicheng Wu b3689cabda [InlineCost] Skip volatile loads when looking for repeated loads
This is a follow-up fix of r320814.  A test case is also added.

llvm-svn: 321075
2017-12-19 13:42:58 +00:00
Ivan A. Kosarev a80c79b5bf [Analysis] Generate more precise TBAA tags when one access encloses the other
There are cases when two tags with different base types denote
accesses to the same direct or indirect member of a structure
type. Currently, merging of such tags results in a tag that
represents an access to an object that has the type of that
member. This patch changes this so that if one of the accesses
encloses the other, then the generic tag is the one of the
enclosed access.

Differential Revision: https://reviews.llvm.org/D39557

llvm-svn: 321019
2017-12-18 20:05:20 +00:00
Sean Fertile 5fb624a3b8 [Memcpy Loop Lowering] Remove the fixed int8 lowering.
Switch over to the lowering that uses target supplied operand types.

Differential Revision: https://reviews.llvm.org/D41201

llvm-svn: 320989
2017-12-18 15:31:14 +00:00
Max Kazantsev 1acab00229 [LVI] Support for ashr in LVI
Enhance LVI to analyze the ‘ashr’ binary operation. This leverages the infrastructure in ConstantRange for the ashr operation.

Patch by Surya Kumari Jangala!

Differential Revision: https://reviews.llvm.org/D40886

llvm-svn: 320983
2017-12-18 14:23:30 +00:00
Igor Laevsky 7bd3fb15e1 [TargetLibraryInfo] Discard library functions with incorrectly sized integers
Differential Revision: https://reviews.llvm.org/D41184

llvm-svn: 320964
2017-12-18 10:31:58 +00:00
Hal Finkel 2ff24731bb [SimplifyLibCalls] Inline calls to cabs when it's safe to do so
When unsafe algerbra is allowed calls to cabs(r) can be replaced by:

  sqrt(creal(r)*creal(r) + cimag(r)*cimag(r))

Patch by Paul Walker, thanks!

Differential Revision: https://reviews.llvm.org/D40069

llvm-svn: 320901
2017-12-16 01:26:25 +00:00
Sanjay Patel 600d24b49c [TargetLibraryInfo] fix documentation comment; NFC
llvm-svn: 320842
2017-12-15 18:54:29 +00:00
Haicheng Wu a446151552 [InlineCost] Find repeated loads in the callee
SROA analysis of InlineCost can figure out that some stores can be removed
after inlining and then the repeated loads clobbered by these stores are also
free.  This patch finds these clobbered loads and adjust the inline cost
accordingly.

Differential Revision: https://reviews.llvm.org/D33946

llvm-svn: 320814
2017-12-15 14:34:41 +00:00
Serguei Katkov 67da7696a0 [SCEV] Fix the movement of insertion point in expander. PR35406.
We cannot move the insertion point to header if SCEV contains div/rem
operations due to they may go over check for zero denominator.

Reviewers: sanjoy, mkazantsev, sebpop
Reviewed By: sebpop
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41229

llvm-svn: 320789
2017-12-15 05:24:42 +00:00