Commit Graph

1692 Commits

Author SHA1 Message Date
Simon Pilgrim 9a2ee1ea2d Add BROADCAST shuffle cost tests.
Part of a lot of cleanup necessary before PR39368.

llvm-svn: 345025
2018-10-23 13:14:54 +00:00
Simon Pilgrim 051feee5c2 Add BROADCAST shuffle cost tests.
Part of a lot of cleanup necessary before PR39368.

llvm-svn: 345023
2018-10-23 13:00:22 +00:00
Simon Pilgrim 8c3d87b8cf [ARM] Regenerate reverse shuffle costs
Came about while cleaning up general shuffle costs for PR39368

llvm-svn: 344966
2018-10-22 22:26:00 +00:00
Simon Pilgrim acd10b9f6c [CostModel][X86] Add some initial extract/insert subvector shuffle cost tests
Just f64/i64 tests initially to demonstrate PR39368

llvm-svn: 344857
2018-10-20 17:38:33 +00:00
Simon Pilgrim e612ab0c80 [CostModel][X86] Add integer vector reduction cost tests
llvm-svn: 344846
2018-10-20 14:29:59 +00:00
Thomas Lively fa54e56d84 [ConstantFolding] Constant fold minimum and maximum intrinsics
Summary: Depends on D52764

Reviewers: aheejin, dschuff

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D52765

llvm-svn: 344796
2018-10-19 18:15:32 +00:00
Anna Thomas 6f732bfb79 [LV] Teach vectorizer about variant value store into uniform address
Summary:
Teach vectorizer about vectorizing variant value stores to uniform
address. Similar to rL343028, we do not allow vectorization if we have
multiple stores to the same uniform address.

Cost model already has the change for considering the extract
instruction cost for a variant value store. See added test cases for how
vectorization is done.
The patch also contains changes to the ORE messages.

Reviewers: Ayal, mkuper, anemet, hsaito

Subscribers: rkruppe, llvm-commits

Differential Revision: https://reviews.llvm.org/D52656

llvm-svn: 344613
2018-10-16 15:46:26 +00:00
Max Kazantsev fdfd98ceec [SCEV] Limit AddRec "simplifications" to avoid combinatorial explosions
SCEV's transform that turns `{A1,+,A2,+,...,+,An}<L> * {B1,+,B2,+,...,+,Bn}<L>` into
a single AddRec of size `2n+1` with complex combinatorial coefficients can easily
trigger exponential growth of the SCEV (in case if nothing gets folded and simplified).
We tried to restrain this transform using the option `scalar-evolution-max-add-rec-size`,
but its default value seems to be insufficiently small: the test attached to this patch
with default value of this option `16` has a SCEV of >3M symbols (when printed out).

This patch reduces the simplification limit. It is not a cure to combinatorial
explosions, but at least it reduces this corner case to something more or less
reasonable.

Differential Revision: https://reviews.llvm.org/D53282
Reviewed By: sanjoy

llvm-svn: 344584
2018-10-16 05:26:21 +00:00
Jonas Paulsson bf66f38705 [SystemZ] Temporarily disable high VFs with integer div/rem.
Until mischeduler is clever enough to avoid spilling in a vectorized loop
with many (scalar) DLRs it is better to avoid high vectorization factors (8
and above).

llvm-svn: 344129
2018-10-10 09:30:29 +00:00
Jonas Paulsson 2c8b33770c [SystemZ] Take better care when computing needed vector registers in TTI.
A new function getNumVectorRegs() is better to use for the number of needed
vector registers instead of getNumberOfParts(). This is to make sure that the
number of vector registers (and typically operations) required for a vector
type is accurate.

getNumberOfParts() which was previously used works by splitting the vector
type until it is legal gives incorrect results for types with a non
power of two number of elements (rare).

A new static function getScalarSizeInBits() that also checks for a pointer
type and returns 64U for it since otherwise it gets a value of 0). Used in a
few places where Ty may be pointer.

Review: Ulrich Weigand
llvm-svn: 344115
2018-10-10 07:36:27 +00:00
George Burgess IV d98d505c0d [Analysis] Make LocationSize pretty-printing more descriptive
This is the third patch in a series intended to make
https://reviews.llvm.org/D44748 more easily reviewable. Please see that
patch for more context. The second being r344013.

The intent is to make the output of printing a LocationSize more
precise. The main motivation for this is that we plan to add a bit to
distinguish whether a given LocationSize is an upper-bound or is
precise; making that information available in pretty-printing is nice.

llvm-svn: 344108
2018-10-10 01:35:22 +00:00
Anna Thomas b1e3d45318 [LV][LAA] Vectorize loop invariant values stored into loop invariant address
Summary:
We are overly conservative in loop vectorizer with respect to stores to loop
invariant addresses.
More details in https://bugs.llvm.org/show_bug.cgi?id=38546
This is the first part of the fix where we start with vectorizing loop invariant
values to loop invariant addresses.

This also includes changes to ORE for stores to invariant address.

Reviewers: anemet, Ayal, mkuper, mssimpso

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D50665

llvm-svn: 343028
2018-09-25 20:57:20 +00:00
Jonas Paulsson 77df2f2f38 [SystemZ] Adjust cost functions for subtargets that use LI + LOC instead of IPM
After recent improvements which makes better use of LOC instead of IPM, the
TTI cost functions also needs to be updated to reflect this.

This involves sext, zext and xor of i1.

The tests were updated so that for z13 the new costs are expected, while the
old costs are still checked for on zEC12.

Review: Ulrich Weigand
https://reviews.llvm.org/D51339

llvm-svn: 342207
2018-09-14 06:46:55 +00:00
Peter Collingbourne c7d281905b Prevent Constant Folding From Optimizing inrange GEP
This patch does the following things:

1. update SymbolicallyEvaluateGEP so that it bails out if it cannot preserve inrange arribute;
2. update llvm/test/Analysis/ConstantFolding/gep.ll to remove UB in it;
3. remove inaccurate comment above ConstantFoldInstOperandsImpl in llvm/lib/Analysis/ConstantFolding.cpp;
4. add a new regression test that makes sure that no optimizations change an inrange GEP in an unexpected way.

Patch by Zhaomo Yang!

Differential Revision: https://reviews.llvm.org/D51698

llvm-svn: 341888
2018-09-11 01:53:36 +00:00
Philip Reames 9f09161290 [AST] Add test coverage of memsets
Immediately after posting https://reviews.llvm.org/D51895, I noticed a small bug.  These tests would have caught that.

llvm-svn: 341880
2018-09-10 23:14:30 +00:00
Philip Reames 5660bd460b [AST] Visit memtransfer arguments in order
The only point to this change is the test diffs.  When I remove this code entirely (in favor of the recently added generic handling), I don't want there to be any confusion due to spurious test diffs.

As an aside, the fact out tests are AST construction order dependent is not great.  I thought about fixing that, but the reasonable schemes I might want (e.g. sort by name) need the test diffs anyways.

Philip

llvm-svn: 341841
2018-09-10 16:00:27 +00:00
Tim Northover 12c1f7675f InstCombine: move hasOneUse check to the top of foldICmpAddConstant
There were two combines not covered by the check before now, neither of which
actually differed from normal in the benefit analysis.

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

llvm-svn: 341831
2018-09-10 14:26:44 +00:00
Matt Arsenault 72d27f5525 AMDGPU: Fix tests using old number for constant address space
llvm-svn: 341770
2018-09-10 02:54:25 +00:00
Philip Reames cb8b3278e5 [AST] Generalize argument specific aliasing
AliasSetTracker has special case handling for memset, memcpy and memmove which pre-existed argmemonly on functions and readonly and writeonly on arguments. This patch generalizes it using the AA infrastructure to any call correctly annotated.

The motivation here is to cut down on confusion, not performance per se. For most instructions, there is a direct mapping to alias set. However, this is not guaranteed by the interface and was not in fact true for these three intrinsics *and only these three intrinsics*. I kept getting myself confused about this invariant, so I figured it would be good to clearly distinguish between a instructions and alias sets. Calls happened to be an easy target.

The nice side effect is that custom implementations of memset/memcpy/memmove - including wrappers discovered by IPO - can now be optimized the same as builts by LICM.

Note: The actual removal of the memset/memtransfer specific handling will happen in a follow on NFC patch.  It was originally part of this one, but separate for ease of review and rebase.

Differential Revision: https://reviews.llvm.org/D50730

llvm-svn: 341713
2018-09-07 21:36:11 +00:00
Nicola Zaghen 9588ad9611 [InstCombine] Fold icmp ugt/ult (add nuw X, C2), C --> icmp ugt/ult X, (C - C2)
Support for sgt/slt was added in rL294898, this adds the same cases also for unsigned compares.

This is the Alive proof: https://rise4fun.com/Alive/nyY

Differential Revision: https://reviews.llvm.org/D50972

llvm-svn: 341353
2018-09-04 10:29:48 +00:00
Nicolai Haehnle 65c026259e Move test/Analysis/DivergenceAnalysis/AMDGPU/loads.ll
Should fix failures of buildbots that don't build the AMDGPU backend.

Change-Id: I01cb84b4b47803b10c5b21ea0353546239860a51
llvm-svn: 341079
2018-08-30 15:24:00 +00:00
Nicolai Haehnle 35617ed4cb [NFC] Rename the DivergenceAnalysis to LegacyDivergenceAnalysis
Summary:
This is patch 1 of the new DivergenceAnalysis (https://reviews.llvm.org/D50433).

The purpose of this patch is to free up the name DivergenceAnalysis for the new generic
implementation. The generic implementation class will be shared by specialized
divergence analysis classes.

Patch by: Simon Moll

Reviewed By: nhaehnle

Subscribers: jvesely, jholewinski, arsenm, nhaehnle, mgorny, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D50434

Change-Id: Ie8146b11be2c50d5312f30e11c7a3036a15b48cb
llvm-svn: 341071
2018-08-30 14:21:36 +00:00
Sanjay Patel 7a05641fa8 [InstCombine] remove unnecessary shuffle undef folding
Add a test for constant folding to show that 
(shuffle undef, undef, mask)
should already be handled via instsimplify.

llvm-svn: 340926
2018-08-29 13:24:34 +00:00
Kit Barton 7c80f98b69 [PPC] Remove Darwin support from POWER backend.
This patch issues an error message if Darwin ABI is attempted with the PPC
backend. It also cleans up existing test cases, either converting the test to
use an alternative triple or removing the test if the coverage is no longer
needed.

Updated Tests
-------------
The majority of test cases were updated to use a different triple that does not
include the Darwin ABI. Many tests were also updated to use FileCheck, in place
of grep.

Deleted Tests
-------------
llvm/test/tools/dsymutil/PowerPC/sibling.test was originally added to test
specific functionality of dsymutil using an object file created with an old
version of llvm-gcc for a Powerbook G4. After a discussion with @JDevlieghere he
suggested removing the test.

llvm/test/CodeGen/PowerPC/combine_loads_from_build_pair.ll was converted from a
PPC test to a SystemZ test, as the behavior is also reproducible there.

All other tests that were deleted were specific to the darwin/ppc ABI and no
longer necessary.

Phabricator Review: https://reviews.llvm.org/D50988

llvm-svn: 340795
2018-08-28 01:18:29 +00:00
Craig Topper a72012c206 [X86] Correct the cost of (v4i32 (fptoui (v4f64))) under AVX512F.
Summary: This was inheriting the cost from the AVX table, but should be legal under AVX512.

Reviewers: RKSimon

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D51267

llvm-svn: 340708
2018-08-26 18:47:44 +00:00
John Brawn 980da83f84 [PhiValues] Use callback value handles to invalidate deleted values
The way that PhiValues is integrated with BasicAA it is possible for a pass
which uses BasicAA to pick up an instance of BasicAA that uses PhiValues without
intending to, and then delete values from a function in a way that causes
PhiValues to return dangling pointers to these deleted values. Fix this by
having a set of callback value handles to invalidate values when they're
deleted.

llvm-svn: 340613
2018-08-24 15:48:30 +00:00
Brian Homerding 3ecabd709f [FunctionAttrs] Infer WriteOnly Function Attribute
These changes expand the FunctionAttr logic in order to mark functions as
WriteOnly when appropriate. This is done through an additional bool variable
and extended logic.

Reviewers: hfinkel, jdoerfert

Differential Revision: https://reviews.llvm.org/D48387

llvm-svn: 340537
2018-08-23 15:05:22 +00:00
Philip Reames 6b6d2e0105 [AST] Add a test for attribute intersection
Already works, but I initially convinced myself it doesn't, so add a test which shows it does.  :)

llvm-svn: 340453
2018-08-22 21:10:56 +00:00
Scott Linder 72855e36c5 [AMDGPU] Consider loads from flat addrspace to be potentially divergent
In general we can't assume flat loads are uniform, and cases where we can prove
they are should be handled through infer-address-spaces.

Differential Revision: https://reviews.llvm.org/D50991

llvm-svn: 340343
2018-08-21 21:24:31 +00:00
Philip Reames c3c23e8cf2 [AST] Remove notion of volatile from alias sets [NFCI]
Volatility is not an aliasing property. We used to model volatile as if it had extremely conservative aliasing implications, but that hasn't been true for several years now. So, it doesn't make sense to be in AliasSet.

It also turns out the code is entirely a noop. Outside of the AST code to update it, there was only one user: load store promotion in LICM. L/S promotion doesn't need the check since it walks all the users of the address anyway. It already checks each load or store via !isUnordered which causes us to bail for volatile accesses. (Look at the lines immediately following the two remove asserts.)

There is the possibility of some small compile time impact here, but the only case which will get noticeably slower is a loop with a large number of loads and stores to the same address where only the last one we inspect is volatile. This is sufficiently rare it's not worth optimizing for..

llvm-svn: 340312
2018-08-21 17:59:11 +00:00
Sanjay Patel 3ce999fa41 [ConstantFolding] improve folding of binops with vector undef operand
A non-undef operand may still have undef constant elements, 
so we should always propagate the vector results per-lane.

llvm-svn: 340194
2018-08-20 18:19:02 +00:00
Sanjay Patel 7ff7bd9b3c [ConstantFolding] add tests for binops on vectors with undef elements; NFC
llvm-svn: 340190
2018-08-20 17:31:34 +00:00
Philip Reames 96bc076c3a [AST] Clarify printing of unknown size locations [NFC]
Printing "unknown" is much more clear than an arbitrary large integer

llvm-svn: 340108
2018-08-17 23:17:31 +00:00
Philip Reames 26f6176f38 [AST][Tests] Clarify what each test is doing
llvm-svn: 340100
2018-08-17 21:58:26 +00:00
Philip Reames 9e313167cf [AST[Tests] Shorten tests using noalias params
llvm-svn: 340099
2018-08-17 21:45:57 +00:00
Philip Reames 079c92e201 [AST] Add tests for argmemonly calls [NFC]
First step towards building a test set to rebase D50730 on top of.  Starting with clone of memtransfer tests, more to come.

llvm-svn: 340095
2018-08-17 21:42:18 +00:00
Sanjay Patel 411b86081e [ConstantFolding] add simplifications for funnel shift intrinsics
This is another step towards being able to canonicalize to the funnel shift 
intrinsics in IR (see D49242 for the initial patch). 
We should not have any loss of simplification power in IR between these and 
the equivalent IR constructs.

Differential Revision: https://reviews.llvm.org/D50848

llvm-svn: 340022
2018-08-17 13:23:44 +00:00
Max Kazantsev 7b78d3920c [MustExecute] Fix algorithmic bug in isGuaranteedToExecute. PR38514
The description of `isGuaranteedToExecute` does not correspond to its implementation.
According to description, it should return `true` if an instruction is executed under the
assumption that its loop is *entered*. However there is a sophisticated alrogithm inside
that tries to prove that the instruction is executed if the loop is *exited*, which is not the
same thing for infinite loops. There is an attempt to protect from dealing with infinite loops
by prohibiting loops without exit blocks, however an infinite loop can have exit blocks.

As result of that, MustExecute can falsely consider some blocks that are never entered as
mustexec, and LICM can hoist dangerous instructions out of them basing on this fact.
This may introduce UB to programs which did not contain it initially.

This patch removes the problematic algorithm and replaced it with a one which tries to
prove what is required in description.

Differential Revision: https://reviews.llvm.org/D50558
Reviewed By: reames

llvm-svn: 339984
2018-08-17 06:19:17 +00:00
Sanjay Patel 0ea8d8b951 [ConstantFolding] add tests for funnel shift intrinsics; NFC
No functionality for this yet.

llvm-svn: 339889
2018-08-16 16:10:42 +00:00
Easwaran Raman aca738b742 [BFI] Use rounding while computing profile counts.
Summary:
Profile count of a block is computed by multiplying its block frequency
by entry count and dividing the result by entry block frequency. Do
rounded division in the last step and update test cases appropriately.

Reviewers: davidxl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D50822

llvm-svn: 339835
2018-08-16 00:26:59 +00:00
Max Kazantsev 5a10d127b9 [AliasSetTracker] Do not treat experimental_guard intrinsic as memory writing instruction
The `experimental_guard` intrinsic has memory write semantics to model the thread-exiting
logic, but does not do any actual writes to memory. Currently, `AliasSetTracker` treats it as a
normal memory write. As result, a loop-invariant load cannot be hoisted out of loop because
the guard may possibly alias with it.

This patch makes `AliasSetTracker` so that it doesn't treat guards as memory writes.

Differential Revision: https://reviews.llvm.org/D50497
Reviewed By: reames

llvm-svn: 339753
2018-08-15 06:21:02 +00:00
Max Kazantsev 837418f3f9 [NFC] Add comprehensive test of AliasSetTracker with guards
llvm-svn: 339643
2018-08-14 06:37:39 +00:00
Reid Kleckner 40e7663b1f [BasicAA] Don't assume tail calls with byval don't alias allocas
Summary:
Calls marked 'tail' cannot read or write allocas from the current frame
because the current frame might be destroyed by the time they run.
However, a tail call may use an alloca with byval. Calling with byval
copies the contents of the alloca into argument registers or stack
slots, so there is no lifetime issue. Tail calls never modify allocas,
so we can return just ModRefInfo::Ref.

Fixes PR38466, a longstanding bug.

Reviewers: hfinkel, nlewycky, gbiv, george.burgess.iv

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D50679

llvm-svn: 339636
2018-08-14 01:24:35 +00:00
Max Kazantsev 4e9def57c7 [NFC] Add tests that demonstrate that MustExecute is fundamentally broken
llvm-svn: 339417
2018-08-10 09:20:46 +00:00
Krzysztof Parzyszek 90f3249ce2 [SCEV] Properly solve quadratic equations
Differential Revision: https://reviews.llvm.org/D48283

llvm-svn: 338758
2018-08-02 19:13:35 +00:00
John Brawn cd73fe8989 [BasicAA] Use PhiValuesAnalysis if available when handling phi alias
By using PhiValuesAnalysis we can get all the values reachable from a phi, so
we can be more precise instead of giving up when a phi has phi operands. We
can't make BaseicAA directly use PhiValuesAnalysis though, as the user of
BasicAA may modify the function in ways that PhiValuesAnalysis can't cope with.

For this optional usage to work correctly BasicAAWrapperPass now needs to be not
marked as CFG-only (i.e. it is now invalidated even when CFG is preserved) due
to how the legacy pass manager handles dependent passes being invalidated,
namely the depending pass still has a pointer to the now-dead dependent pass.

Differential Revision: https://reviews.llvm.org/D44564

llvm-svn: 338242
2018-07-30 11:52:08 +00:00
Keno Fischer 864fbd8e9a [SCEV] Don't expand Wrap predicate using inttoptr in ni addrspaces
Summary:
In non-integral address spaces, we're not allowed to introduce inttoptr/ptrtoint
intrinsics. Instead, we need to expand any pointer arithmetic as geps on the
base pointer. Luckily this is a common task for SCEV, so all we have to do here
is hook up the corresponding helper function and add test case.

Fixes PR38290

Reviewers: sanjoy
Differential Revision: https://reviews.llvm.org/D49832

llvm-svn: 338073
2018-07-26 21:55:06 +00:00
Stanislav Mekhanoshin b8269a9589 Fix llvm::ComputeNumSignBits with some operations and llvm.assume
Currently ComputeNumSignBits does early exit while processing some
of the operations (add, sub, mul, and select). This prevents the
function from using AssumptionCacheTracker if passed.

Differential Revision: https://reviews.llvm.org/D49759

llvm-svn: 337936
2018-07-25 16:39:24 +00:00
Roman Tereshin 1ba1f9310c [SCEV] Add zext(C + x + ...) -> D + zext(C-D + x + ...)<nuw><nsw> transform
if the top level addition in (D + (C-D + x + ...)) could be proven to
not wrap, where the choice of D also maximizes the number of trailing
zeroes of (C-D + x + ...), ensuring homogeneous behaviour of the
transformation and better canonicalization of such expressions.

This enables better canonicalization of expressions like

  1 + zext(5 + 20 * %x + 24 * %y)  and
      zext(6 + 20 * %x + 24 * %y)

which get both transformed to

  2 + zext(4 + 20 * %x + 24 * %y)

This pattern is common in address arithmetics and the transformation
makes it easier for passes like LoadStoreVectorizer to prove that 2 or
more memory accesses are consecutive and optimize (vectorize) them.

Reviewed By: mzolotukhin

Differential Revision: https://reviews.llvm.org/D48853

llvm-svn: 337859
2018-07-24 21:48:56 +00:00
Max Kazantsev d41faecc49 [SCEV] Fix buggy behavior in getAddExpr with truncs
SCEV tries to constant-fold arguments of trunc operands in SCEVAddExpr, and when it does
that, it passes wrong flags into the recursion. It is only valid to pass flags that are proved for
narrow type into a computation in wider type if we can prove that trunc instruction doesn't
actually change the value. If it did lose some meaningful bits, we may end up proving wrong
no-wrap flags for sum of arguments of trunc.

In the provided test we end up with `nuw` where it shouldn't be because of this bug.

The solution is to conservatively pass `SCEV::FlagAnyWrap` which is always a valid thing to do.

Reviewed By: sanjoy
Differential Revision: https://reviews.llvm.org/D49471

llvm-svn: 337435
2018-07-19 01:46:21 +00:00
Max Kazantsev 6b12506200 [NFC] Make a test more neat
llvm-svn: 337379
2018-07-18 11:03:40 +00:00
Tim Shen a064622bd3 Re-apply "[SCEV] Strengthen StrengthenNoWrapFlags (reapply r334428)."
llvm-svn: 337075
2018-07-13 23:58:46 +00:00
Tim Renouf f3d8295105 DivergenceAnalysis: added debug output
Summary:
This commit does two things:

1. modified the existing DivergenceAnalysis::dump() so it dumps the
   whole function with added DIVERGENT: annotations;

2. added code to do that dump if the appropriate -debug-only option is
   on.

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D47700

Change-Id: Id97b605aab1fc6f5a11a20c58a99bbe8c565bf83
llvm-svn: 336998
2018-07-13 13:13:30 +00:00
Piotr Padlewski c63b492bcd Simplify recursive launder.invariant.group and strip
Summary:
This patch is crucial for proving equality laundered/stripped
pointers. eg:

  bool foo(A *a) {
    return a == std::launder(a);
  }

Clang with -fstrict-vtable-pointers will emit something like:

    define dso_local zeroext i1 @_Z3fooP1A(%struct.A* %a) {
    entry:
      %c = bitcast %struct.A* %a to i8*
      %call = tail call i8* @llvm.launder.invariant.group.p0i8(i8* %c)
      %0 = bitcast %struct.A* %a to i8*
      %1 = tail call i8* @llvm.strip.invariant.group.p0i8(i8* %0)
      %2 = tail call i8* @llvm.strip.invariant.group.p0i8(i8* %call)
      %cmp = icmp eq i8* %1, %2
      ret i1 %cmp
    }

and because %2 can be replaced with @llvm.strip.invariant.group(%0)
and that %2 and %1 will produce the same value (because strip is readnone)
we can replace compare with true.

Reviewers: rsmith, hfinkel, majnemer, amharc, kuhar

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D47423

llvm-svn: 336963
2018-07-12 23:55:20 +00:00
Simon Pilgrim 667a5b541f [TargetTransformInfo] Add pow2 analysis for scalar constants
Add ConstantInt analysis to getOperandInfo so we get more realistic div/rem expansion costs comparable to the vector costs.

llvm-svn: 336827
2018-07-11 17:51:27 +00:00
Manoj Gupta 77eeac3d9e llvm: Add support for "-fno-delete-null-pointer-checks"
Summary:
Support for this option is needed for building Linux kernel.
This is a very frequently requested feature by kernel developers.

More details : https://lkml.org/lkml/2018/4/4/601

GCC option description for -fdelete-null-pointer-checks:
This Assume that programs cannot safely dereference null pointers,
and that no code or data element resides at address zero.

-fno-delete-null-pointer-checks is the inverse of this implying that
null pointer dereferencing is not undefined.

This feature is implemented in LLVM IR in this CL as the function attribute
"null-pointer-is-valid"="true" in IR (Under review at D47894).
The CL updates several passes that assumed null pointer dereferencing is
undefined to not optimize when the "null-pointer-is-valid"="true"
attribute is present.

Reviewers: t.p.northover, efriedma, jyknight, chandlerc, rnk, srhines, void, george.burgess.iv

Reviewed By: efriedma, george.burgess.iv

Subscribers: eraman, haicheng, george.burgess.iv, drinkcat, theraven, reames, sanjoy, xbolva00, llvm-commits

Differential Revision: https://reviews.llvm.org/D47895

llvm-svn: 336613
2018-07-09 22:27:23 +00:00
Simon Pilgrim dc113dc7ed [CostModel][X86] Add SREM/UREM general and constant costs (PR38056)
We penalize general SDIV/UDIV costs but don't do the same for SREM/UREM.

This patch makes general vector SREM/UREM x20 as costly as scalar, the same approach as we do for SDIV/UDIV. The patch also extends the existing SDIV/UDIV constant costs for SREM/UREM - at the moment this means the additional cost of a MUL+SUB (see D48975).

Differential Revision: https://reviews.llvm.org/D48980

llvm-svn: 336486
2018-07-07 16:53:30 +00:00
Tim Shen 2ed501d656 Revert "[SCEV] Strengthen StrengthenNoWrapFlags (reapply r334428)."
This reverts commit r336140. Our tests shows that LSR assert fails with it.

llvm-svn: 336473
2018-07-06 23:20:35 +00:00
Max Kazantsev 20da7e467a Revert "[InstCombine] Delay foldICmpUsingKnownBits until simple transforms are done"
llvm-svn: 336410
2018-07-06 04:04:13 +00:00
Simon Pilgrim 8c3765dc6b [CostModel][X86] Add UDIV/UREM by pow2 costs
Normally InstCombine would have simplified these to SRL/AND instructions but we may still see these during SLP vectorization etc.

llvm-svn: 336371
2018-07-05 16:56:28 +00:00
Max Kazantsev 3097b76e8c [InstCombine] Delay foldICmpUsingKnownBits until simple transforms are done
This patch changes order of transform in InstCombineCompares to avoid
performing transforms based on ranges which produce complex bit arithmetics
before more simple things (like folding with constants) are done. See PR37636
for the motivating example.

Differential Revision: https://reviews.llvm.org/D48584
Reviewed By: spatel, lebedev.ri

llvm-svn: 336172
2018-07-03 06:23:57 +00:00
Tim Shen c7cef4bcc4 [SCEV] Strengthen StrengthenNoWrapFlags (reapply r334428).
Summary:
Comment on Transforms/LoopVersioning/incorrect-phi.ll: With the change
SCEV is able to prove that the loop doesn't wrap-self (due to zext i16
to i64), disabling the entire loop versioning pass. Removed the zext and
just use i64.

Reviewers: sanjoy

Subscribers: jlebar, hiraditya, javed.absar, bixia, llvm-commits

Differential Revision: https://reviews.llvm.org/D48409

llvm-svn: 336140
2018-07-02 20:01:54 +00:00
Simon Pilgrim ac193d4b5c [CostModel][X86] Add cost tests for fp rounding intrinsics
Add cost tests for fp ceil, floor, nearbyint, rint and trunc.

llvm-svn: 336122
2018-07-02 17:07:01 +00:00
Piotr Padlewski 5b3db45e8f Implement strip.invariant.group
Summary:
This patch introduce new intrinsic -
strip.invariant.group that was described in the
RFC: Devirtualization v2

Reviewers: rsmith, hfinkel, nlopes, sanjoy, amharc, kuhar

Subscribers: arsenm, nhaehnle, JDevlieghere, hiraditya, xbolva00, llvm-commits

Differential Revision: https://reviews.llvm.org/D47103

Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com>
llvm-svn: 336073
2018-07-02 04:49:30 +00:00
Roman Shirokiy 272eac85c7 Fix overconfident assert in ScalarEvolution::isImpliedViaMerge
We can have AddRec with loops having many predecessors.
This changes an assert to an early return.

Differential Revision: https://reviews.llvm.org/D48766

llvm-svn: 335965
2018-06-29 11:46:30 +00:00
John Brawn bdbbd8381f Add a PhiValuesAnalysis pass to calculate the underlying values of phis
This pass is being added in order to make the information available to BasicAA,
which can't do caching of this information itself, but possibly this information
may be useful for other passes.

Incorporates code based on Daniel Berlin's implementation of Tarjan's algorithm.

Differential Revision: https://reviews.llvm.org/D47893

llvm-svn: 335857
2018-06-28 14:13:06 +00:00
Adhemerval Zanella cadcfed7aa [AArch64] Add custom lowering for v4i8 trunc store
This patch adds a custom trunc store lowering for v4i8 vector types.
Since there is not v.4b register, the v4i8 is promoted to v4i16 (v.4h)
and default action for v4i8 is to extract each element and issue 4
byte stores.

A better strategy would be to extended the promoted v4i16 to v8i16
(with undef elements) and extract and store the word lane which
represents the v4i8 subvectores. The construction:

  define void @foo(<4 x i16> %x, i8* nocapture %p) {
    %0 = trunc <4 x i16> %x to <4 x i8>
    %1 = bitcast i8* %p to <4 x i8>*
    store <4 x i8> %0, <4 x i8>* %1, align 4, !tbaa !2
    ret void
  }

Can be optimized from:

  umov    w8, v0.h[3]
  umov    w9, v0.h[2]
  umov    w10, v0.h[1]
  umov    w11, v0.h[0]
  strb    w8, [x0, #3]
  strb    w9, [x0, #2]
  strb    w10, [x0, #1]
  strb    w11, [x0]
  ret

To:

  xtn     v0.8b, v0.8h
  str     s0, [x0]
  ret

The patch also adjust the memory cost for autovectorization, so the C
code:

  void foo (const int *src, int width, unsigned char *dst)
  {
    for (int i = 0; i < width; i++)
       *dst++ = *src++;
  }

can be vectorized to:

  .LBB0_4:                                // %vector.body
                                          // =>This Inner Loop Header: Depth=1
        ldr     q0, [x0], #16
        subs    x12, x12, #4            // =4
        xtn     v0.4h, v0.4s
        xtn     v0.8b, v0.8h
        st1     { v0.s }[0], [x2], #4
        b.ne    .LBB0_4

Instead of byte operations.

llvm-svn: 335735
2018-06-27 13:58:46 +00:00
David Green 8699492304 [DA] Delinearise AddRecs if we can prove they don't wrap
We can prove that some delinearized subscripts do not wrap around to become
negative by the fact that they are from inbound geps of load/store locations.
This helps improve the delinearisation in cases where we can't prove that they
are non-negative from SCEV alone.

Differential Revision: https://reviews.llvm.org/D48481

llvm-svn: 335481
2018-06-25 15:13:26 +00:00
Simon Pilgrim 9c8f9374b5 [CostModel][AArch64] Add some initial costs for SK_Select and SK_PermuteSingleSrc
AArch64 was only setting costs for SK_Transpose, which meant that many of the simpler shuffles (e.g. SK_Select and SK_PermuteSingleSrc for larger vector elements) was being severely overestimated by the default shuffle expansion.

This patch adds costs to help improve SLP performance and avoid a regression in reductions introduced by D48174.

I'm not very knowledgeable about AArch64 shuffle lowering so I've kept the extra costs to a minimum - someone who knows this code can add extra costs which should improve vectorization a lot more.

Differential Revision: https://reviews.llvm.org/D48172

llvm-svn: 335329
2018-06-22 09:45:31 +00:00
Tim Shen 63f244c4f4 [SCEV] Re-apply r335197 (with Polly fixes).
Summary:
This initiates a discussion on changing Polly accordingly while re-applying r335197 (D48338).

I have never worked on Polly. The proposed change to param_div_div_div_2.ll is not educated, but just patterns that match the output.

All LLVM files are already reviewed in D48338.

Reviewers: jdoerfert, bollu, efriedma

Subscribers: jlebar, sanjoy, hiraditya, llvm-commits, bixia

Differential Revision: https://reviews.llvm.org/D48453

llvm-svn: 335292
2018-06-21 21:29:54 +00:00
Nicolai Haehnle 1045928aab AMDGPU: Convert test cases to the dimension-aware intrinsics
Summary:
Also explicitly port over some tests in llvm.amdgcn.image.* that were
missing. Some tests are removed because they no longer apply (i.e.
explicitly testing building an address vector via insertelement).

This is in preparation for the eventual removal of the old-style
intrinsics.

Some additional notes:
- constant-address-space-32bit.ll: change some GCN-NEXT to GCN because
  the instruction schedule was subtly altered
- insert_vector_elt.ll: the old test didn't actually test anything,
  because %tmp1 was not used; remove the load, because it doesn't work
  (Because of the amdgpu_ps calling convention? In any case, it's
  orthogonal to what the test claims to be testing.)

Change-Id: Idfa99b6512ad139e755e82b8b89548ab08f0afcf

Reviewers: arsenm, rampitec

Subscribers: MatzeB, qcolombet, kzhuravl, wdng, yaxunl, dstuttard, tpr, t-tye, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D48018

llvm-svn: 335229
2018-06-21 13:37:19 +00:00
David Green d143c65de3 [DA] Enable -da-delinearize by default
This enables da-delinearize in Dependence Analysis for delinearizing array
accesses into multiple dimensions. This can help to increase the power of
Dependence analysis on multi-dimensional arrays and prevent having to fall
back to the slower and less accurate MIV tests. It adds static checks on the
bounds of the arrays to ensure that one dimension doesn't overflow into
another, and brings our code in line with our tests.

Differential Revision: https://reviews.llvm.org/D45872

llvm-svn: 335217
2018-06-21 11:53:16 +00:00
Simon Pilgrim 2a9cde026c [X86][AVX] Reduce v4f64/v4i64 shuffle costs (PR37882)
These were being over cautious for costs for one/two op general shuffles - VSHUFPD doesn't have to replicate the same shuffle in both lanes like VSHUFPS does. 

llvm-svn: 335216
2018-06-21 11:37:13 +00:00
Tim Shen 433b9761ce Revert "[SCEV] Improve zext(A /u B) and zext(A % B)"
This reverts commit r335197, as some bots are not happy.

llvm-svn: 335198
2018-06-21 02:15:32 +00:00
Tim Shen 5af61e0a28 [SCEV] Improve zext(A /u B) and zext(A % B)
Summary:
Try to match udiv and urem patterns, and sink zext down to the leaves.

I'm not entirely sure why some unrelated tests change, but the added <nsw>s seem right.

Reviewers: sanjoy

Subscribers: jlebar, hiraditya, bixia, llvm-commits

Differential Revision: https://reviews.llvm.org/D48338

llvm-svn: 335197
2018-06-21 01:49:07 +00:00
Roman Lebedev 42a1ff11fb [NFC][SCEV] Add tests related to bit masking (PR37793)
Summary:
Related to https://bugs.llvm.org/show_bug.cgi?id=37793, https://reviews.llvm.org/D46760#1127287

We'd like to do this canonicalization https://rise4fun.com/Alive/Gmc
But it is currently restricted by rL155136 / rL155362, which says:
```
    // This is a constant shift of a constant shift. Be careful about hiding
    // shl instructions behind bit masks. They are used to represent multiplies
    // by a constant, and it is important that simple arithmetic expressions
    // are still recognizable by scalar evolution.
    //
    // The transforms applied to shl are very similar to the transforms applied
    // to mul by constant. We can be more aggressive about optimizing right
    // shifts.
    //
    // Combinations of right and left shifts will still be optimized in
    // DAGCombine where scalar evolution no longer applies.
```

I think these tests show that for *constants*, SCEV has no issues with that canonicalization.

Reviewers: mkazantsev, spatel, efriedma, sanjoy

Reviewed By: mkazantsev

Subscribers: sanjoy, javed.absar, llvm-commits, stoklund, bixia

Differential Revision: https://reviews.llvm.org/D48229

llvm-svn: 335101
2018-06-20 07:54:11 +00:00
Sanjoy Das 6e9b355cc9 Revert "[SCEV] Add nuw/nsw to mul ops in StrengthenNoWrapFlags"
This reverts r334428.  It incorrectly marks some multiplications as nuw.  Tim
Shen is working on a proper fix.

Original commit message:

[SCEV] Add nuw/nsw to mul ops in StrengthenNoWrapFlags where safe.

Summary:
Previously we would add them for adds, but not multiplies.

llvm-svn: 335016
2018-06-19 04:09:44 +00:00
George Burgess IV aa283d80fe [MSSA] Print more optimization information
In particular, when asked to print a MemoryAccess, we'll now print where
defs are optimized to, and we'll print optimized access types.

This patch also introduces an operator<< to make printing AliasResults
easier.

Patch by Juneyoung Lee!

Differential Revision: https://reviews.llvm.org/D47860

llvm-svn: 334760
2018-06-14 19:55:53 +00:00
Justin Lebar fe455464eb [SCEV] Simplify zext/trunc idiom that appears when handling bitmasks.
Summary:
Specifically, we transform

  zext(2^K * (trunc X to iN)) to iM ->
  2^K * (zext(trunc X to i{N-K}) to iM)<nuw>

This is helpful because pulling the 2^K out of the zext allows further
optimizations.

Reviewers: sanjoy

Subscribers: hiraditya, llvm-commits, timshen

Differential Revision: https://reviews.llvm.org/D48158

llvm-svn: 334737
2018-06-14 17:13:48 +00:00
Justin Lebar b326904dba [SCEV] Simplify trunc-of-add/mul to add/mul-of-trunc under more circumstances.
Summary:
Previously we would do this simplification only if it did not introduce
any new truncs (excepting new truncs which replace other cast ops).

This change weakens this condition: If the number of truncs stays the
same, but we're able to transform trunc(X + Y) to X + trunc(Y), that's
still simpler, and it may open up additional transformations.

While we're here, also clean up some duplicated code.

Reviewers: sanjoy

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D48160

llvm-svn: 334736
2018-06-14 17:13:35 +00:00
Simon Pilgrim 607a1e2196 [CostModel][AArch64] Add cost tests for ALTERNATE/SELECT style shuffle masks
Precursor to fixing a regression with SLP vectorizer for supporting SELECT shuffles (vs the current ALTERNATE)

llvm-svn: 334714
2018-06-14 14:20:20 +00:00
Simon Pilgrim 32702cc86a [CostModel] Recognise REVERSE shuffle mask if the elements come from the second src
llvm-svn: 334698
2018-06-14 09:35:00 +00:00
Simon Pilgrim 9fd634db22 [CostModel][X86] Test showing failure to recognise REVERSE shuffle mask if the elements come from the second src
llvm-svn: 334623
2018-06-13 17:12:11 +00:00
Simon Pilgrim 54a138a0c5 [CostModel] Recognise BROADCAST shuffle mask if the elements come from the second src
llvm-svn: 334620
2018-06-13 16:52:02 +00:00
Simon Pilgrim 5af0b99ea4 [CostModel][X86] Test showing failure to recognise BROADCAST shuffle mask if the elements come from the second src
llvm-svn: 334616
2018-06-13 16:33:42 +00:00
Max Kazantsev 0ed79620c6 [SimplifyIndVars] Ignore dead users
IndVarSimplify sometimes makes transforms basing on users that are trivially dead. In particular,
if DCE wasn't run before it, there may be a dead `sext/zext` in loop that will trigger widening
transforms, however it makes no sense to do it.

This patch teaches IndVarsSimplify ignore the mist trivial cases of that.

Differential Revision: https://reviews.llvm.org/D47974
Reviewed By: sanjoy

llvm-svn: 334567
2018-06-13 02:25:32 +00:00
Simon Pilgrim e39fa6cbbb [CostModel] Replace ShuffleKind::SK_Alternate with ShuffleKind::SK_Select (PR33744)
As discussed on PR33744, this patch relaxes ShuffleKind::SK_Alternate which requires shuffle masks to only match an alternating pattern from its 2 sources:

e.g. v4f32: <0,5,2,7> or <4,1,6,3>

This seems far too restrictive as most SIMD hardware which will implement it using a general blend/bit-select instruction, so replaces it with SK_Select, permitting elements from either source as long as they are inline:

e.g. v4f32: <0,5,2,7>, <4,1,6,3>, <0,1,6,7>, <4,1,2,3> etc.

This initial patch just updates the name and cost model shuffle mask analysis, later patch reviews will update SLP to better utilise this - it still limits itself to SK_Alternate style patterns.

Differential Revision: https://reviews.llvm.org/D47985

llvm-svn: 334513
2018-06-12 16:12:29 +00:00
Simon Pilgrim 0783921987 [CostModel] Treat Identity shuffle masks as zero cost
As discussed on D47985, identity shuffle masks should probably be free.

I've limited this to the case where the input and output types all match - but we could probably accept all cases.

Differential Revision: https://reviews.llvm.org/D47986

llvm-svn: 334506
2018-06-12 14:47:13 +00:00
Simon Pilgrim cfd96329f0 [CostModel][X86] Add extra Identity shuffle mask cost tests (D47986)
llvm-svn: 334486
2018-06-12 09:18:13 +00:00
Tim Shen df2d6652c1 Fix incorrect CHECK-LABEL
llvm-svn: 334434
2018-06-11 19:56:12 +00:00
Justin Lebar 4da41c13a5 [SCEV] Add transform zext((A * B * ...)<nuw>) --> (zext(A) * zext(B) * ...)<nuw>.
Reviewers: sanjoy

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D48041

llvm-svn: 334429
2018-06-11 18:57:58 +00:00
Justin Lebar aa4fec94d8 [SCEV] Add nuw/nsw to mul ops in StrengthenNoWrapFlags where safe.
Summary:
Previously we would add them for adds, but not multiplies.

Reviewers: sanjoy

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D48038

llvm-svn: 334428
2018-06-11 18:57:42 +00:00
Tim Shen cc63761720 [SCEV] Canonicalize "A /u C1 /u C2" to "A /u (C1*C2)".
Summary: FWIW InstCombine already folds this. Also avoid the case where C1*C2 overflows.

Reviewers: sunfish, sanjoy

Subscribers: hiraditya, bixia, llvm-commits

Differential Revision: https://reviews.llvm.org/D47965

llvm-svn: 334425
2018-06-11 18:44:58 +00:00
Simon Pilgrim 5297506625 [CostModel][X86] Add 'select' style shuffle costs tests (PR33744)
llvm-svn: 334351
2018-06-09 16:08:25 +00:00
Krzysztof Parzyszek b10ea39270 [SCEV] Look through zero-extends in howFarToZero
An expression like
  (zext i2 {(trunc i32 (1 + %B) to i2),+,1}<%while.body> to i32)
will become zero exactly when the nested value becomes zero in its type.
Strip injective operations from the input value in howFarToZero to make
the value simpler.

Differential Revision: https://reviews.llvm.org/D47951

llvm-svn: 334318
2018-06-08 20:43:07 +00:00
Artur Pilipenko 4d063e7bb1 [BPI] Apply invoke heuristic before loop branch heuristic
Currently the loop branch heuristic is applied before the invoke heuristic which makes us overestimate the probability of the unwind destination of invokes inside loops. This in turn makes us grossly underestimate the frequencies of loops with invokes.

Reviewed By: skatkov, vsk

Differential Revision: https://reviews.llvm.org/D47371

llvm-svn: 334285
2018-06-08 13:03:21 +00:00
Simon Pilgrim f2f043acbb [X86][SSE] Use multiplication scale factors for v8i16 SHL on pre-AVX2 targets.
Similar to v4i32 SHL, convert v8i16 shift amounts to scale factors instead to improve performance and reduce instruction count. We were already doing this for constant shifts, this adds variable shift support.

Reduces the serial nature of the codegen, which relies on chains of plendvb/pand+pandn+por shifts.

This is a step towards adding support for vXi16 vector rotates.

Differential Revision: https://reviews.llvm.org/D47546

llvm-svn: 334023
2018-06-05 15:17:39 +00:00
Karl-Johan Karlsson 6d52e5c3e4 [ConstantFold] Disallow folding vector geps into bitcasts
Summary:
Getelementptr returns a vector of pointers, instead of a single address,
when one or more of its arguments is a vector. In such case it is not
possible to simplify the expression by inserting a bitcast of operand(0)
into the destination type, as it will create a bitcast between different
sizes.

Reviewers: majnemer, mkuper, mssimpso, spatel

Reviewed By: spatel

Subscribers: lebedev.ri, llvm-commits

Differential Revision: https://reviews.llvm.org/D46379

llvm-svn: 333783
2018-06-01 19:34:35 +00:00
Karl-Johan Karlsson b60b920a8c [ConstantFold] Add lit testcase for bitcast problem. NFC
llvm-svn: 333767
2018-06-01 15:08:14 +00:00
David Green 2911b3a07a [DA] Fix direction vectors for weakZeroSrcSIV
Both weakZeroSrcSIV and weakZeroDstSIV are currently giving the same
direction vectors. Fix weakZeroSrcSIVtest by flipping the directions
it gives.

Differential Revision: https://reviews.llvm.org/D46678

llvm-svn: 333658
2018-05-31 14:55:29 +00:00
Daniel Neilson 6b23fb764e [AliasSet] Teach the alias set how to handle atomic memcpy/memmove/memset
Summary:
The atomic variants of the memcpy/memmove/memset intrinsics can be treated
the same was as the regular forms, with respect to aliasing. Update the
AliasSetTracker to treat the atomic forms the same was as the regular forms.

llvm-svn: 333551
2018-05-30 14:43:39 +00:00
Daniel Neilson 3a6c50f4e0 [BasicAA] Teach the analysis about atomic memcpy
Summary:
A simple change to derive mod/ref info from the atomic memcpy
intrinsic in the same way as from the regular memcpy intrinsic.

llvm-svn: 333454
2018-05-29 19:23:50 +00:00
Piotr Padlewski d6f7346a4b Fix aliasing of launder.invariant.group
Summary:
Patch for capture tracking broke
bootstrap of clang with -fstict-vtable-pointers
which resulted in debbugging nightmare. It was fixed
https://reviews.llvm.org/D46900 but as it turned
out, there were other parts like inliner (computing of
noalias metadata) that I found after bootstraping with enabled
assertions.

Reviewers: hfinkel, rsmith, chandlerc, amharc, kuhar

Subscribers: JDevlieghere, eraman, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D47088

llvm-svn: 333070
2018-05-23 09:16:44 +00:00
Simon Pilgrim 4162d77744 [TTI] Add uniform/non-uniform constant Pow2 detection to TargetTransformInfo::getInstructionThroughput
This enables us to detect more fast path sdiv cases under cost analysis.

This patch also enables us to handle non-uniform-constant pow2 cases for X86 SDIV costs.

Found while working on D46276

Future patches can then extend the vectorizers to more fully support non-uniform pow2 cases.

Differential Revision: https://reviews.llvm.org/D46637

llvm-svn: 332969
2018-05-22 10:40:09 +00:00
Piotr Padlewski 5642a42442 Propagate nonnull and dereferenceable throught launder
Summary:
invariant.group.launder should not stop propagation
of nonnull and dereferenceable, because e.g. we would not be
able to hoist loads speculatively.

Reviewers: rsmith, amharc, kuhar, xbolva00, hfinkel

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D46972

llvm-svn: 332788
2018-05-18 23:54:33 +00:00
Piotr Padlewski 153fe60079 [MemDep] Fixed handling of invariant.group
Summary:
Memdep had funny bug related to invariant.groups - because it did not
invalidated cache, in some very rare cases it was possible to show memory
dependence of the instruction that was deleted, but because other
instruction took it's place it resulted in call to vtable!
Thanks @amharc for repro!.

Reviewers: dberlin, kuhar, amharc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45320

Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com>
llvm-svn: 332781
2018-05-18 22:40:34 +00:00
Serguei Katkov 5095883fe9 [LICM] Extend the MustExecute scope
CanProveNotTakenFirstIteration utility does not handle the case when
condition of the branch is a constant. Add its handling.

Reviewers: reames, anna, mkazantsev
Reviewed By: reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46996

llvm-svn: 332695
2018-05-18 04:56:28 +00:00
George Burgess IV c6526176cf Revert r332657: "[AA] cfl-anders-aa with field sensitivity"
I don't believe the person who LGTMed this review has appropriate
context on this code. I apologize if I'm wrong.

llvm-svn: 332674
2018-05-17 21:56:39 +00:00
David Bolvansky b1c59e3f30 [AA] cfl-anders-aa with field sensitivity
Summary:
There was some unfinished work started for offset tracking in CFLGraph by the author of implementation of Andersen algorithm. This work was completed and support for field sensitivity was added to the core of Andersen algorithm.

The performance results seem promising.

SPEC2006 int_base score was increased by 1.1 % (I  compared clang 6.0 with clang 6.0 with this patch). The avergae compile time was increased by +- 1 % according my measures with small and medium C/C++ projects (I did not tested it on the large projects with milions of lines of code)

Reviewers: chandlerc, george.burgess.iv, rja

Reviewed By: rja

Subscribers: rja, llvm-commits

Differential Revision: https://reviews.llvm.org/D46282

llvm-svn: 332657
2018-05-17 20:23:33 +00:00
Krzysztof Pszeniczny 2ba8fd4914 [BasicAA] Fix handling of invariant group launders
Summary:
A recent patch ([[ https://reviews.llvm.org/rL331587 | rL331587 ]]) to Capture Tracking taught it that the `launder_invariant_group` intrinsic captures its argument only by returning it. Unfortunately, BasicAA still considered every call instruction as a possible escape source and hence concluded that the result of a `launder_invariant_group` call cannot alias any local non-escaping value. This led to [[ https://bugs.llvm.org/show_bug.cgi?id=37458 | bug 37458 ]].

This patch updates the relevant check for escape sources in BasicAA.

Reviewers: Prazek, kuhar, rsmith, hfinkel, sanjoy, xbolva00

Reviewed By: hfinkel, xbolva00

Subscribers: JDevlieghere, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D46900

llvm-svn: 332466
2018-05-16 13:16:54 +00:00
Michael Zolotukhin 67cfbaac89 [MemorySSA] Don't sort IDF blocks.
Summary:
After r332167 we started to sort the IDF blocks inside IDF calculation, so
there is no need to re-sort them on the user site. The test changes are due to
a slightly different order we're using now (originally we used DFSInNumber and
now the blocks are sorted by a pair (LevelFromRoot, DFSInNumber)).

Reviewers: dberlin, mgrang

Subscribers: Prazek, hiraditya, george.burgess.iv, llvm-commits

Differential Revision: https://reviews.llvm.org/D46899

llvm-svn: 332385
2018-05-15 18:40:29 +00:00
George Burgess IV 175400a801 Add regression test for r331976
In general, it's difficult to poke the ConstantExpr code in CFLAA, since
LLVM is so great at eagerly reducing ConstantExprs. :)

Sadly, this only shows a functional difference from before the patch
because CFLAA has some special logic around taking loads of non-pointers
into account. Namely, with the broken select behavior, CFLAA will
completely fail to take note of @g3. Since CFLAA doesn't have any record
about @g3 when we do an alias query for @g3 and %a, it conservatively
answers MayAlias. When we properly take @g3 into account with the new
select logic, we get NoAlias for this query.

I suspect that the aforementioned "special logic" isn't completely
correct, but this test-case should prevent future wonky aliasing results
from appearing for these flavors of ConstantExprs, so I think it's still
worth having.

llvm-svn: 332017
2018-05-10 18:37:54 +00:00
Serguei Katkov 32754aa37f [SCEV] Add missed Test for rL331949.
llvm-svn: 331950
2018-05-10 01:42:59 +00:00
Adhemerval Zanella f384bc7166 [AArch64] Improve cost of vector division by constant
With custom lowering for vector MULLH{S,U}, it is now profitable to
vectorize a divide by constant loop for the custom types (v16i8, v8i16,
and v4i32).  The cost if based on TargetLowering::Build{S,U}DIV which
uses a multiply by constant plus adjustment to express a divide by
constant.

Both {u,s}mull{2} are expressed as Instruction::Mul and shifts by
Instruction::AShr.

llvm-svn: 331873
2018-05-09 12:48:22 +00:00
Simon Pilgrim fe5c5277ed [CostModel][X86] Split off SLM checks
A future patch will require this and the diff is much better if we perform the split separately.

llvm-svn: 331867
2018-05-09 11:42:34 +00:00
Shiva Chen 2c864551df [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +00:00
Piotr Padlewski 5dde809404 Rename invariant.group.barrier to launder.invariant.group
Summary:
This is one of the initial commit of "RFC: Devirtualization v2" proposal:
https://docs.google.com/document/d/16GVtCpzK8sIHNc2qZz6RN8amICNBtvjWUod2SujZVEo/edit?usp=sharing

Reviewers: rsmith, amharc, kuhar, sanjoy

Subscribers: arsenm, nhaehnle, javed.absar, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D45111

llvm-svn: 331448
2018-05-03 11:03:01 +00:00
Max Kazantsev 58fce7e54b Re-enable "[SCEV] Make computeExitLimit more simple and more powerful"
This patch was temporarily reverted because it has exposed bug 37229 on
PowerPC platform. The bug is unrelated to the patch and was just a general
bug in the optimization done for PowerPC platform only. The bug was fixed
by the patch rL331410.

This patch returns the disabled commit since the bug was fixed.

llvm-svn: 331427
2018-05-03 02:37:55 +00:00
Piotr Padlewski f801205e48 Mark invariant.group.barrier as inaccessiblememonly
It turned out that readonly argmemonly is not enough.

  store 42, %p
  %b = barrier(%p)
  store 43, %b
the first store is dead, but because barrier was marked as
reading argument memory, it was considered alive. With
inaccessiblememonly it doesn't read the argument, but
it also can't be CSEd.

based on: https://reviews.llvm.org/D32006

llvm-svn: 331338
2018-05-02 08:22:07 +00:00
Mikhail Maltsev ffaa8a8781 [IR] Do not assume that function pointers are aligned
Summary:
The value tracking analysis uses function alignment to infer that the
least significant bits of function pointers are known to be zero.
Unfortunately, this is not correct for ARM targets: the least
significant bit of a function pointer stores the ARM/Thumb state
information (i.e., the LSB is set for Thumb functions and cleared for
ARM functions).

The original approach (https://reviews.llvm.org/D44781) introduced a
new field for function pointer alignment in the DataLayout structure
to address this. But it seems unlikely that optimizations based on
function pointer alignment would bring much benefit in practice to
justify the additional maintenance burden, so this patch simply
assumes that function pointer alignment is always unknown.

Reviewers: javed.absar, efriedma

Reviewed By: efriedma

Subscribers: kristof.beyls, llvm-commits, hfinkel, rogfer01

Differential Revision: https://reviews.llvm.org/D46110

llvm-svn: 331025
2018-04-27 09:12:12 +00:00
Matthew Simpson b4096ebe26 [TTI, AArch64] Add transpose shuffle kind
This patch adds a new shuffle kind useful for transposing a 2xn matrix. These
transpose shuffle masks read corresponding even- or odd-numbered vector
elements from two n-dimensional source vectors and write each result into
consecutive elements of an n-dimensional destination vector. The transpose
shuffle kind is meant to model the TRN1 and TRN2 AArch64 instructions. As such,
this patch also considers transpose shuffles in the AArch64 implementation of
getShuffleCost.

Differential Revision: https://reviews.llvm.org/D45982

llvm-svn: 330941
2018-04-26 13:48:33 +00:00
Max Kazantsev 2c287ec9c5 Revert "[SCEV] Make computeExitLimit more simple and more powerful"
This reverts commit 023c8be90980e0180766196cba86f81608b35d38.

This patch triggers miscompile of zlib on PowerPC platform. Most likely it is
caused by some pre-backend PPC-specific pass, but we don't clearly know the
reason yet. So we temporally revert this patch with intention to return it
once the problem is resolved. See bug 37229 for details.

llvm-svn: 330893
2018-04-26 02:07:40 +00:00
Simon Pilgrim 0ae4bba911 [CostModel][X86] Add div/rem tests for non-uniform constant divisors
llvm-svn: 330852
2018-04-25 18:03:31 +00:00
Matthew Simpson 3fd67df3f8 [AArch64] Add cost model test case for transpose
This patch adds a cost model test case for vector shuffles having transpose
masks. The given costs are inaccurate and will be updated in a follow-on patch.

llvm-svn: 330625
2018-04-23 18:21:29 +00:00
Simon Pilgrim ab9798765c [CostModel][X86] Add vector element insert/extract cost tests
llvm-svn: 330439
2018-04-20 15:26:59 +00:00
Simon Pilgrim 863ffeb750 [CostModel][X86] Add srem/urem constant cost tests
llvm-svn: 330436
2018-04-20 15:01:03 +00:00
Simon Pilgrim 8a15d72550 [CostModel][X86] Add SLM/GLM/BtVer2 compare + division/remainder cost tests
llvm-svn: 330435
2018-04-20 14:50:34 +00:00
Simon Pilgrim cd9ccf8824 [CostModel][X86] Split off BtVer2 cost checks
llvm-svn: 330433
2018-04-20 13:50:33 +00:00
Simon Pilgrim 25b7782975 [CostModel][X86] Add GoldmontPlus cost tests
Just reuses goldmont costs atm

llvm-svn: 330432
2018-04-20 13:42:53 +00:00
Shiva Chen c84e77aeae [BasicAA] Return MayAlias for the pointer plus variable offset to
structure object member

Differential Revision: https://reviews.llvm.org/D45510

llvm-svn: 330106
2018-04-16 01:58:39 +00:00
Simon Pilgrim 34b397a318 [CostModel][X86] Add some specific cpu targets to the cost models
We're mostly testing with generic isa attributes, but PR36550 will require testing of specific target's scheduler models as well.

llvm-svn: 330056
2018-04-13 19:30:15 +00:00
Simon Pilgrim 3ede11b58c [CostModel][X86] Split fma arith costs tests from other fp tests
Was proving cumbersome to test with/without fma

llvm-svn: 330054
2018-04-13 19:12:32 +00:00
Simon Pilgrim 237730a196 [CostModel][X86] Regenerate latency/codesize cost tests
llvm-svn: 330052
2018-04-13 18:56:58 +00:00
Simon Pilgrim 0c07ccc4e3 [CostModel][X86] Regenerate cast conversion cost tests
llvm-svn: 330051
2018-04-13 18:56:05 +00:00
Simon Pilgrim e30db80d30 [CostModel][X86] Regenerate masked intrinsic cost tests
llvm-svn: 330050
2018-04-13 18:54:16 +00:00
David Green 5ef933b02c [DA] Improve alias checking in dependence analysis
Improve the alias analysis to account for cases where we
know that src/dst pairs cannot alias due to things like
TBAA. As we know they are noalias, we know no dependency
can occur. Also fixes issues around the size parameter
to AA being incorrect.

Differential Revision: https://reviews.llvm.org/D42381

llvm-svn: 329692
2018-04-10 11:37:21 +00:00
Simon Pilgrim 8a8ff4f6d4 [CostModel][X86] Regenerate vector reduction cost tests with update_analyze_test_checks.py
NOTE: We're only really interested in the extractelement cost (which represents the entire reduction).
llvm-svn: 329504
2018-04-07 14:20:10 +00:00
Simon Pilgrim 7bd5ff8b4a [CostModel][X86] Regenerate vector select cost tests with update_analyze_test_checks.py
llvm-svn: 329502
2018-04-07 14:09:54 +00:00
Simon Pilgrim 495b660269 [CostModel][X86] Regenerate vector integer truncation cost tests with update_analyze_test_checks.py
llvm-svn: 329500
2018-04-07 14:05:35 +00:00
Simon Pilgrim 84d8498fc5 [CostModel][X86] Regenerate silvermont (and added goldmont) cost tests with update_analyze_test_checks.py
llvm-svn: 329499
2018-04-07 14:02:14 +00:00
Simon Pilgrim 80ce1dde44 [CostModel][X86] Fix v32i16/v64i8 SETCC costs on AVX512BW targets
llvm-svn: 329498
2018-04-07 13:24:33 +00:00
Simon Pilgrim a49a1b9ccc [CostModel][X86] Regenerate vector comparison cost tests with update_analyze_test_checks.py
llvm-svn: 329497
2018-04-07 12:47:35 +00:00
Simon Pilgrim 61f704e4bd [CostModel][X86] Regenerate bit count cost tests with update_analyze_test_checks.py
llvm-svn: 329413
2018-04-06 16:14:27 +00:00
Simon Pilgrim 63ae5579e7 [CostModel][X86] Regenerate vector shuffle cost tests with update_analyze_test_checks.py
llvm-svn: 329410
2018-04-06 16:00:28 +00:00
Simon Pilgrim d55ad63bfe [CostModel][X86] Regenerate bswap/bitreverse cost tests with update_analyze_test_checks.py
llvm-svn: 329407
2018-04-06 15:46:26 +00:00
Simon Pilgrim 74402acb00 [CostModel][X86] Regenerate integer extension/truncation cost tests with update_analyze_test_checks.py
llvm-svn: 329402
2018-04-06 15:28:26 +00:00
Simon Pilgrim 06fba8b204 [CostModel][X86] Regenerate integer division/remainder tests with update_analyze_test_checks.py
llvm-svn: 329401
2018-04-06 15:23:26 +00:00
Simon Pilgrim 60fc843fc6 [CostModel][X86] Regenerate vector shift cost tests with update_analyze_test_checks.py
llvm-svn: 329400
2018-04-06 15:14:34 +00:00
Simon Pilgrim ad768585ff [CostModel][X86] Regenerate int<->fp cost tests with update_analyze_test_checks.py
llvm-svn: 329398
2018-04-06 15:12:36 +00:00
Simon Pilgrim 5334a2c571 [UpdateTestChecks] Add update_analyze_test_checks.py for cost model analysis generation
The script allows the auto-generation of checks for cost model tests to speed up their creation and help improve coverage, which will help a lot with PR36550.

If the need arises we can add support for other analyze passes as well, but the cost models was the one I needed to get done - at the moment it just warns that any other analysis mode is unsupported.

I've regenerated a couple of x86 test files to show the effect.

Differential Revision: https://reviews.llvm.org/D45272

llvm-svn: 329390
2018-04-06 12:36:27 +00:00
Simon Pilgrim d152d55ab2 [X86][CostModel] Use generic SSE levels instead of particular CPUs for shuffle costs
llvm-svn: 329168
2018-04-04 11:14:12 +00:00
Nicolai Haehnle 2f5a73820c AMDGPU: Dimension-aware image intrinsics
Summary:
These new image intrinsics contain the texture type as part of
their name and have each component of the address/coordinate as
individual parameters.

This is a preparatory step for implementing the A16 feature, where
coordinates are passed as half-floats or -ints, but the Z compare
value and texel offsets are still full dwords, making it difficult
or impossible to distinguish between A16 on or off in the old-style
intrinsics.

Additionally, these intrinsics pass the 'texfailpolicy' and
'cachectrl' as i32 bit fields to reduce operand clutter and allow
for future extensibility.

v2:
- gather4 supports 2darray images
- fix a bug with 1D images on SI

Change-Id: I099f309e0a394082a5901ea196c3967afb867f04

Reviewers: arsenm, rampitec, b-sumner

Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, llvm-commits, t-tye

Differential Revision: https://reviews.llvm.org/D44939

llvm-svn: 329166
2018-04-04 10:58:54 +00:00
Max Kazantsev c01e47b43f [SCEV] Make computeExitLimit more simple and more powerful
Current implementation of `computeExitLimit` has a big piece of code
the only purpose of which is to prove that after the execution of this
block the latch will be executed. What it currently checks is actually a
subset of situations where the exiting block dominates latch.

This patch replaces all these checks for simple particular cases with
domination check over loop's latch which is the only necessary condition
of taking the exiting block into consideration. This change allows to
calculate exact loop taken count for simple loops like

  for (int i = 0; i < 100; i++) {
    if (cond) {...} else {...}
    if (i > 50) break;
    . . .
  }

Differential Revision: https://reviews.llvm.org/D44677
Reviewed By: efriedma

llvm-svn: 329047
2018-04-03 05:57:19 +00:00
George Burgess IV 3588fd4865 [MemorySSA] Consider callsite args for hashing and equality.
We use a `DenseMap<MemoryLocOrCall, MemlocStackInfo>` to keep track of
prior work when optimizing uses in MemorySSA. Because we weren't
accounting for callsite arguments in either the hash code or equality
tests for `MemoryLocOrCall`s, we optimized uses too aggressively in
some rare cases.

Fix by Daniel Berlin.

Should fix PR36883.

llvm-svn: 328748
2018-03-29 00:54:39 +00:00
Max Kazantsev 7094c8deb2 [SCEV] Make exact taken count calculation more optimistic
Currently, `getExact` fails if it sees two exit counts in different blocks. There is
no solid reason to do so, given that we only calculate exact non-taken count
for exiting blocks that dominate latch. Using this fact, we can simply take min
out of all exits of all blocks to get the exact taken count.

This patch makes the calculation more optimistic with enforcing our assumption
with asserts. It allows us to calculate exact backedge taken count in trivial loops
like

  for (int i = 0; i < 100; i++) {
    if (i > 50) break;
    . . .
  }

Differential Revision: https://reviews.llvm.org/D44676
Reviewed By: fhahn

llvm-svn: 328611
2018-03-27 07:30:38 +00:00
Craig Topper a985919d3e [X86] Update cost model for Goldmont. Add fsqrt costs for Silvermont
Add fdiv costs for Goldmont using table 16-17 of the Intel Optimization Manual. Also add overrides for FSQRT for Goldmont and Silvermont.

Reviewers: RKSimon

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D44644

llvm-svn: 328451
2018-03-25 15:58:12 +00:00
Philip Reames 37a1a29fcb [MustExecute] Shwo the effect of using full loop info variant
Most basic possible test for the logic used by LICM.

Also contains a speculative build fix for compiles which complain about a definition of a stuct K; followed by a declaration as class K;

llvm-svn: 328058
2018-03-20 23:00:54 +00:00
Philip Reames 164b1b4e21 [MustExecute] Add simplest possible test for LoopSafetyOnfo
(Currently showing without, will enable and check in diff to show impact)

llvm-svn: 328056
2018-03-20 22:55:20 +00:00
Philip Reames ce998adf0a [MustExecute] Use the annotation style printer
As suggested in the original review (https://reviews.llvm.org/D44524), use an annotation style printer instead.

Note: The switch from -analyze to -disable-output in tests was driven by the fact that seems to be the idiomatic style used in annoation passes.  I tried to keep both working, but the old style pass API for printers really doesn't make this easy.  It invokes (runOnFunction, print(Module)) repeatedly.  I decided the extra state wasn't worth it given the old pass manager is going away soonish anyway.
llvm-svn: 328015
2018-03-20 18:43:44 +00:00
Philip Reames 89f2241770 Add an analysis printer for must execute reasoning
Many of our loop passes make use of so called "must execute" or "guaranteed to execute" facts to prove the legality of code motion. The basic notion is that we know (by assumption) an instruction didn't fault at it's original location, so if the location we move it to is strictly post dominated by the original, then we can't have introduced a new fault.

At the moment, the testing for this logic is somewhat adhoc and done mostly through LICM. Since I'm working on that code, I want to improve the testing. This patch is the first step in that direction. It doesn't actually test the variant used by the loop passes - I need to move that to the Analysis library first - but instead exercises an alternate implementation used by SCEV. (I plan on merging both implementations.)

Note: I'll be replacing the printing logic within this with an annotation based version in the near future.  Anna suggested this in review, and it seems like a strictly better format.  

Differential Revision: https://reviews.llvm.org/D44524

llvm-svn: 328004
2018-03-20 17:09:21 +00:00
Serguei Katkov 529f42331e [SCEV] Re-land: Fix isKnownPredicate
This is re-land of https://reviews.llvm.org/rL327362 with a fix
and regression test.

The crash was due to it is possible that for found MDL loop,
LHS or RHS may contain an invariant unknown SCEV which
does not dominate the MDL. Please see regression
test for an example.

Reviewers: sanjoy, mkazantsev, reames
Reviewed By: mkazantsev
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D44553

llvm-svn: 327822
2018-03-19 06:35:30 +00:00
Matthew Simpson eacfefd056 [AArch64] Implement getArithmeticReductionCost
This patch provides an implementation of getArithmeticReductionCost for
AArch64. We can specialize the cost of add reductions since they are computed
using the 'addv' instruction.

Differential Revision: https://reviews.llvm.org/D44490

llvm-svn: 327702
2018-03-16 11:34:15 +00:00
Matthew Simpson 883e96c9d4 [TTI, AArch64] Allow the cost model analysis to test vector reduce intrinsics
This patch considers the experimental vector reduce intrinsics in the default
implementation of getIntrinsicInstrCost. The cost of these intrinsics is
computed with getArithmeticReductionCost and getMinMaxReductionCost. This patch
also adds a test case for AArch64 that indicates the costs we currently compute
for vector reduce intrinsics. These costs are inaccurate and will be updated in
a follow-on patch.

Differential Revision: https://reviews.llvm.org/D44489

llvm-svn: 327698
2018-03-16 10:00:30 +00:00
Matthew Simpson c1c4ad6e64 [ConstantFolding, InstSimplify] Handle more vector GEPs
This patch addresses some additional cases where the compiler crashes upon
encountering vector GEPs. This should fix PR36116.

Differential Revision: https://reviews.llvm.org/D44219
Reference: https://bugs.llvm.org/show_bug.cgi?id=36116

llvm-svn: 327638
2018-03-15 16:00:29 +00:00
Evandro Menezes f9bd871d32 [AArch64] Adjust the cost of integer vector division
Since there is no instruction for integer vector division, factor in the
cost of singling out each element to be used with the scalar division
instruction.

Differential revision: https://reviews.llvm.org/D43974

llvm-svn: 326955
2018-03-07 22:35:32 +00:00
Sebastian Pop bf6e1c26cf DA: remove uses of GEP, only ask SCEV
It's been quite some time the Dependence Analysis (DA) is broken,
as it uses the GEP representation to "identify" multi-dimensional arrays.
It even wrongly detects multi-dimensional arrays in single nested loops:

from test/Analysis/DependenceAnalysis/Coupled.ll, example @couple6
;; for (long int i = 0; i < 50; i++) {
;; A[i][3*i - 6] = i;
;; *B++ = A[i][i];

DA used to detect two subscripts, which makes no sense in the LLVM IR
or in C/C++ semantics, as there are no guarantees as in Fortran of
subscripts not overlapping into a next array dimension:

maximum nesting levels = 1
SrcPtrSCEV = %A
DstPtrSCEV = %A
using GEPs
subscript 0
    src = {0,+,1}<nuw><nsw><%for.body>
    dst = {0,+,1}<nuw><nsw><%for.body>
    class = 1
    loops = {1}
subscript 1
    src = {-6,+,3}<nsw><%for.body>
    dst = {0,+,1}<nuw><nsw><%for.body>
    class = 1
    loops = {1}
Separable = {}
Coupled = {1}

With the current patch, DA will correctly work on only one dimension:

maximum nesting levels = 1
SrcSCEV = {(-2424 + %A)<nsw>,+,1212}<%for.body>
DstSCEV = {%A,+,404}<%for.body>
subscript 0
    src = {(-2424 + %A)<nsw>,+,1212}<%for.body>
    dst = {%A,+,404}<%for.body>
    class = 1
    loops = {1}
Separable = {0}
Coupled = {}

This change removes all uses of GEP from DA, and we now only rely
on the SCEV representation.

The patch does not turn on -da-delinearize by default, and so the DA analysis
will be more conservative in the case of multi-dimensional memory accesses in
nested loops.

I disabled some interchange tests, as the DA is not able to disambiguate
the dependence anymore. To make DA stronger, we may need to
compute a bound on the number of iterations based on the access functions
and array dimensions.

The patch cleans up all the CHECKs in test/Transforms/LoopInterchange/*.ll to
avoid checking for snippets of LLVM IR: this form of checking is very hard to
maintain. Instead, we now check for output of the pass that are more meaningful
than dozens of lines of LLVM IR. Some tests now require -debug messages and thus
only enabled with asserts.

Patch written by Sebastian Pop and Aditya Kumar.

Differential Revision: https://reviews.llvm.org/D35430

llvm-svn: 326837
2018-03-06 21:55:59 +00:00
Simon Pilgrim 74ff6ff437 [X86] Add silvermont fp arithmetic cost model tests
Add silvermont to existing high coverage tests instead of repeating in slm-arith-costs.ll

llvm-svn: 326747
2018-03-05 22:13:22 +00:00
Max Kazantsev f8d2969abb [SCEV] Smart range calculation for SCEVUnknown Phis
The range of SCEVUnknown Phi which merges values `X1, X2, ..., XN`
can be evaluated as `U(Range(X1), Range(X2), ..., Range(XN))`.

Reviewed By: sanjoy
Differential Revision: https://reviews.llvm.org/D43810

llvm-svn: 326418
2018-03-01 06:56:48 +00:00
Simon Pilgrim 9929f90740 [X86][SSE] Reduce FADD/FSUB/FMUL costs on later targets (PR36280)
Agner's tables indicate that for SSE42+ targets (Core2 and later) we can reduce the FADD/FSUB/FMUL costs down to 1, which should fix the Himeno benchmark.

Note: the AVX512 FDIV costs look rather dodgy, but this isn't part of this patch.

Differential Revision: https://reviews.llvm.org/D43733

llvm-svn: 326133
2018-02-26 22:10:17 +00:00
John Brawn 29bbed3613 [BPI] Detect branches in loops that make themselves not taken
If we have a loop like this:
 int n = 0;
 while (...) {
  if (++n >= MAX) {
    n = 0;
  }
 }
then the body of the 'if' statement will only be executed once every MAX
iterations. Detect this by looking for branches in loops where taking the branch
makes the branch condition evaluate to 'not taken' in the next iteration of the
loop, and reduce the probability of such branches.

This slightly improves EEMBC benchmarks on cortex-m4/cortex-m33 due to making
better choices in if-conversion, but has no effect on any other cpu/benchmark
that I could detect.

Differential Revision: https://reviews.llvm.org/D35804

llvm-svn: 325925
2018-02-23 17:17:31 +00:00
Sanjay Patel e6143904b9 revert r325515: [TTI CostModel] change default cost of FP ops to 1 (PR36280)
There are too many perf regressions resulting from this, so we need to 
investigate (and add tests for) targets like ARM and AArch64 before 
trying to reinstate.

llvm-svn: 325658
2018-02-21 01:42:52 +00:00
Sanjay Patel 3e8a76abfd [TTI CostModel] change default cost of FP ops to 1 (PR36280)
This change was mentioned at least as far back as:
https://bugs.llvm.org/show_bug.cgi?id=26837#c26
...and I found a real program that is harmed by this: 
Himeno running on AMD Jaguar gets 6% slower with SLP vectorization:
https://bugs.llvm.org/show_bug.cgi?id=36280
...but the change here appears to solve that bug only accidentally.

The div/rem costs for x86 look very wrong in some cases, but that's already true, 
so we can fix those in follow-up patches. There's also evidence that more cost model
changes are needed to solve SLP problems as shown in D42981, but that's an independent 
problem (though the solution may be adjusted after this change is made).

Differential Revision: https://reviews.llvm.org/D43079

llvm-svn: 325515
2018-02-19 16:11:44 +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
Simon Pilgrim cb9a02f60e [X86][SSE] Increase PMULLD costs to better match hardware
Until Skylake, most hardware could only issue a PMULLD op every other cycle

llvm-svn: 324823
2018-02-10 19:27:10 +00:00
Yaxun Liu 2a22c5deff [AMDGPU] Switch to the new addr space mapping by default
This requires corresponding clang change.

Differential Revision: https://reviews.llvm.org/D40955

llvm-svn: 324101
2018-02-02 16:07:16 +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
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
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
Daniel Neilson 1e68724d24 Remove alignment argument from memcpy/memmove/memset in favour of alignment attributes (Step 1)
Summary:
 This is a resurrection of work first proposed and discussed in Aug 2015:
   http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.html
and initially landed (but then backed out) in Nov 2015:
   http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

 The @llvm.memcpy/memmove/memset intrinsics currently have an explicit argument
which is required to be a constant integer. It represents the alignment of the
dest (and source), and so must be the minimum of the actual alignment of the
two.

 This change is the first in a series that allows source and dest to each
have their own alignments by using the alignment attribute on their arguments.

 In this change we:
1) Remove the alignment argument.
2) Add alignment attributes to the source & dest arguments. We, temporarily,
   require that the alignments for source & dest be equal.

 For example, code which used to read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 100, i32 4, i1 false)
will now read
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 4 %dest, i8* align 4 %src, i32 100, i1 false)

 Downstream users may have to update their lit tests that check for
@llvm.memcpy/memmove/memset call/declaration patterns. The following extended sed script
may help with updating the majority of your tests, but it does not catch all possible
patterns so some manual checking and updating will be required.

s~declare void @llvm\.mem(set|cpy|move)\.p([^(]*)\((.*), i32, i1\)~declare void @llvm.mem\1.p\2(\3, i1)~g
s~call void @llvm\.memset\.p([^(]*)i8\(i8([^*]*)\* (.*), i8 (.*), i8 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i8(i8\2* \3, i8 \4, i8 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i16\(i8([^*]*)\* (.*), i8 (.*), i16 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i16(i8\2* \3, i8 \4, i16 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i32\(i8([^*]*)\* (.*), i8 (.*), i32 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i32(i8\2* \3, i8 \4, i32 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i64\(i8([^*]*)\* (.*), i8 (.*), i64 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i64(i8\2* \3, i8 \4, i64 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i128\(i8([^*]*)\* (.*), i8 (.*), i128 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i128(i8\2* \3, i8 \4, i128 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i8\(i8([^*]*)\* (.*), i8 (.*), i8 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i8(i8\2* align \6 \3, i8 \4, i8 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i16\(i8([^*]*)\* (.*), i8 (.*), i16 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i16(i8\2* align \6 \3, i8 \4, i16 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i32\(i8([^*]*)\* (.*), i8 (.*), i32 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i32(i8\2* align \6 \3, i8 \4, i32 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i64\(i8([^*]*)\* (.*), i8 (.*), i64 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i64(i8\2* align \6 \3, i8 \4, i64 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i128\(i8([^*]*)\* (.*), i8 (.*), i128 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i128(i8\2* align \6 \3, i8 \4, i128 \5, i1 \7)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i8\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i8 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i8(i8\3* \4, i8\5* \6, i8 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i16\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i16 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i16(i8\3* \4, i8\5* \6, i16 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i32\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i32 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i32(i8\3* \4, i8\5* \6, i32 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i64\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i64 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i64(i8\3* \4, i8\5* \6, i64 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i128\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i128 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i128(i8\3* \4, i8\5* \6, i128 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i8\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i8 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i8(i8\3* align \8 \4, i8\5* align \8 \6, i8 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i16\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i16 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i16(i8\3* align \8 \4, i8\5* align \8 \6, i16 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i32\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i32 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i32(i8\3* align \8 \4, i8\5* align \8 \6, i32 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i64\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i64 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i64(i8\3* align \8 \4, i8\5* align \8 \6, i64 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i128\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i128 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i128(i8\3* align \8 \4, i8\5* align \8 \6, i128 \7, i1 \9)~g

 The remaining changes in the series will:
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
   source and dest alignments.
Step 3) Update Clang to use the new IRBuilder API.
Step 4) Update Polly to use the new IRBuilder API.
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
        getDestAlignment() and getSourceAlignment() instead.
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
        MemIntrinsicInst::[get|set]Alignment() methods.

Reviewers: pete, hfinkel, lhames, reames, bollu

Reviewed By: reames

Subscribers: niosHD, reames, jholewinski, qcolombet, jfb, sanjoy, arsenm, dschuff, dylanmckay, mehdi_amini, sdardis, nemanjai, david2050, nhaehnle, javed.absar, sbc100, jgravelle-google, eraman, aheejin, kbarton, JDevlieghere, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, llvm-commits

Differential Revision: https://reviews.llvm.org/D41675

llvm-svn: 322965
2018-01-19 17:13:12 +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
Brian M. Rzycki 9b7ae23256 [JumpThreading] Preservation of DT and LVI across the pass
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.

Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.

LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perform the
preversation was minimally altered and simply marked as
preserved for the PassManager to be informed.

This extends the analysis available to JumpThreading for
future enhancements such as threading across loop headers.

Reviewers: dberlin, kuhar, sebpop

Reviewed By: kuhar, sebpop

Subscribers: mgorny, dmgreen, kuba, rnk, rsmith, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D40146

llvm-svn: 322401
2018-01-12 21:06:48 +00:00
Craig Topper d58c165545 [X86] Make v2i1 and v4i1 legal types without VLX
Summary:
There are few oddities that occur due to v1i1, v8i1, v16i1 being legal without v2i1 and v4i1 being legal when we don't have VLX. Particularly during legalization of v2i32/v4i32/v2i64/v4i64 masked gather/scatter/load/store. We end up promoting the mask argument to these during type legalization and then have to widen the promoted type to v8iX/v16iX and truncate it to get the element size back down to v8i1/v16i1 to use a 512-bit operation. Since need to fill the upper bits of the mask we have to fill with 0s at the promoted type.

It would be better if we could just have the v2i1/v4i1 types as legal so they don't undergo any promotion. Then we can just widen with 0s directly in a k register. There are no real v4i1/v2i1 instructions anyway. Everything is done on a larger register anyway.

This also fixes an issue that we couldn't implement a masked vextractf32x4 from zmm to xmm properly.

We now have to support widening more compares to 512-bit to get a mask result out so new tablegen patterns got added.

I had to hack the legalizer for widening the operand of a setcc a bit so it didn't try create a setcc returning v4i32, extract from it, then try to promote it using a sign extend to v2i1. Now we create the setcc with v4i1 if the original setcc's result type is v2i1. Then extract that and don't sign extend it at all.

There's definitely room for improvement with some follow up patches.

Reviewers: RKSimon, zvi, guyblank

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41560

llvm-svn: 321967
2018-01-07 18:20:37 +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
Reid Kleckner cd78ddc119 Revert "[JumpThreading] Preservation of DT and LVI across the pass"
This reverts r321825, it causes crashes in Chromium. Reproducer
forthcoming.

llvm-svn: 321832
2018-01-04 23:23:46 +00:00
Brian M. Rzycki cdad6c0b60 [JumpThreading] Preservation of DT and LVI across the pass
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.

Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.

LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perfom the
preversation was minimally altered and was simply marked
as preserved for the PassManager to be informed.

This extends the analysis available to JumpThreading for
future enhancements. One example is loop boundary threading.

Reviewers: dberlin, kuhar, sebpop

Reviewed By: kuhar, sebpop

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D40146

llvm-svn: 321825
2018-01-04 21:57:32 +00:00
Nikolai Bozhenov 4d5e34b221 [ValueTracking] Adding missed lit-test for commit r316208
Reviewers: reames, hfinkel

Differential Revision: https://reviews.llvm.org/D34101

Patch by: Olga Chupina <olga.chupina@intel.com>

llvm-svn: 321792
2018-01-04 10:02:50 +00:00
Benjamin Kramer 0af3be4560 Fix tests after move to utohexstr.
llvm-svn: 321527
2017-12-28 17:00:37 +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 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
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
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
Bjorn Steinbrink 030123e8e8 Give up on array allocas in getPointerDereferenceableBytes
Summary:
As suggested by Eli Friedman, don't try to handle array allocas here,
because of possible overflows, instead rely on instcombine converting
them to allocations of array types.

Reviewers: efriedma

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41398

llvm-svn: 321159
2017-12-20 10:01:30 +00:00
Bjorn Steinbrink 2da4d9d86d Treat sret arguments as being dereferenceable in getPointerDereferenceableBytes()
Reviewers: rnk, hfinkel, efriedma

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41355

llvm-svn: 321061
2017-12-19 08:46:46 +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
Craig Topper 7034d401f8 [X86] Use mattr instead of mcpu in some of the cost model tests.
Based on the names of the check lines, features seems more appropriate that cpu.

Spotted while prototyping my patch to make 512-bit vectors illegal on SKX sometimes.

llvm-svn: 320959
2017-12-18 07:21:58 +00:00
Bjorn Steinbrink 3603de2fa2 Re-commit "Properly handle multi-element and dynamically sized allocas in getPointerDereferenceableBytes()""
llvm-clang-x86_64-expensive-checks-win is still broken, so the failure
seems unrelated.

llvm-svn: 320953
2017-12-17 21:20:16 +00:00
Bjorn Steinbrink 6f7bbf349f Revert "Properly handle multi-element and dynamically sized allocas in getPointerDereferenceableBytes()"
This reverts commit 217067d5179882de9deb60d2e866befea4c126e7.

Fails on llvm-clang-x86_64-expensive-checks-win

llvm-svn: 320945
2017-12-17 15:16:58 +00:00
Bjorn Steinbrink c27f81b92b Properly handle byval arguments in getPointerDereferenceableBytes()
Summary:
For byval arguments, the number of dereferenceable bytes is equal to
the size of the pointee, not the pointer.

Reviewers: hfinkel, rnk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41305

llvm-svn: 320939
2017-12-17 02:37:42 +00:00
Bjorn Steinbrink 5d86532467 Properly handle multi-element and dynamically sized allocas in getPointerDereferenceableBytes()
Reviewers: hfinkel, rnk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41288

llvm-svn: 320938
2017-12-17 01:54:25 +00:00