Commit Graph

19641 Commits

Author SHA1 Message Date
Volkan Keles 4ecdb44a64 BlockExtractor: Don’t delete functions directly
Blocks may have function calls, so don’t erase functions
directly to avoid erasing a function that has a user.

llvm-svn: 327340
2018-03-12 22:28:18 +00:00
Saleem Abdulrasool 8b342680bf ObjCARC: teach the cloner about funclets
In the case that the CallInst that is being moved has an associated
operand bundle which is a funclet, the move will construct an invalid
instruction.  The new site will have a different token and needs to be
reassociated with the new instruction.

Unfortunately, there is no way to alter the bundle after the
construction of the instruction.  Replace the call instruction cloning
with a custom helper to clone the instruction and reassociate the
funclet token.

llvm-svn: 327336
2018-03-12 21:46:09 +00:00
Vedant Kumar 3a408538f0 Remove the LoopInstSimplify pass (-loop-instsimplify)
LoopInstSimplify is unused and untested. Reading through the commit
history the pass also seems to have a high maintenance burden.

It would be best to retire the pass for now. It should be easy to
recover if we need something similar in the future.

Differential Revision: https://reviews.llvm.org/D44053

llvm-svn: 327329
2018-03-12 20:49:42 +00:00
Michael Zolotukhin a3d8ef0f08 Improve caching scheme in ProvenanceAnalysis.
Summary:
ProvenanceAnalysis::related(A, B) currently memoizes its results, and on big
tests the cache grows too large, and we're spending most of the time
growing/looking through DenseMap.

This patch reduces the size of the cache by normalizing keys first: we do that
by calling GetUnderlyingObjCPtr on the input values. The results of
GetUnderlyingObjCPtr are also memoized in a separate cache.

The patch doesn't bring noticable changes to compile time on CTMark, however
significantly helps one of our internal tests.

Reviewers: gottesmm

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D44270

llvm-svn: 327328
2018-03-12 20:36:25 +00:00
Craig Topper ee99aa4dd0 [InstCombine] Replace calls to getNumUses with hasNUses or hasNUsesOrMore
getNumUses is a linear time operation. It traverses the user linked list to the end and counts as it goes. Since we are only interested in small constant counts, we should use hasNUses or hasNUsesMore more that terminate the traversal as soon as it can provide the answer.

There are still two other locations in InstCombine, but changing those would force a rebase of D44266 which if accepted would remove them.

Differential Revision: https://reviews.llvm.org/D44398

llvm-svn: 327315
2018-03-12 18:46:05 +00:00
Craig Topper 3b4ad9c12d [CallSiteSplitting] Use !Instruction::use_empty instead of checking for a non-zero return from getNumUses
getNumUses is a linear operation. It walks a linked list to get a count. So in this case its better to just ask if there are any users rather than how many.

llvm-svn: 327314
2018-03-12 18:40:59 +00:00
Eugene Leviant 19e238746b [ThinLTO] Recommit of import global variables
This wasreverted in r326638 due to link problems and fixed
afterwards

llvm-svn: 327254
2018-03-12 10:30:50 +00:00
Justin Lebar 24b6640b1b Back out "Re-land: Teach CorrelatedValuePropagation to reduce the width of udiv/urem instructions."
This reverts r326908, originally landed as D44102.

Reverted for causing performance regressions on x86.  (These regressions
are not yet understood.)

llvm-svn: 327252
2018-03-12 09:26:09 +00:00
Florian Hahn a7dcfa746e [PartialInlining] Use isInlineViable to detect constructs preventing inlining.
Use isInlineViable to prevent inlining of functions with non-inlinable
constructs, in case cost analysis is skipped.

Reviewers: efriedma, sfertile, davide, davidxl

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D42846

llvm-svn: 327207
2018-03-10 14:53:44 +00:00
Ulrich Weigand 019dd2316d Revert "[Debug] Retain both sets of debug intrinsics in HoistThenElseCodeToIf"
This reverts commit r327175 as problems in debug info generation were shown.

llvm-svn: 327176
2018-03-09 22:00:10 +00:00
Ulrich Weigand fa4e63c0d6 [Debug] Retain both sets of debug intrinsics in HoistThenElseCodeToIf
When hoisting common code from the "then" and "else" branches of a condition
to before the "if", there is no need to require that debug intrinsics match
before moving them (and merging them).  Instead, we can simply always keep
all debug intrinsics from both sides of the "if".

This fixes PR36410, which describes a problem where as a result of the attempt
to merge debug locations for two debug intrinsics we end up with an invalid
intrinsic, where the scope indicated in the !dbg location no longer matches
the scope of the variable tracked by the intrinsic.

In addition, this has the benefit that we no longer throw away information
that is actually still valid, helping to generate better debug data.

Reviewed By: vsk

Differential Revision: https://reviews.llvm.org/D44312

llvm-svn: 327175
2018-03-09 21:37:07 +00:00
Renato Golin 038ede2a16 [NFC] Consolidate six getPointerOperand() utility functions into one place
There are six separate instances of getPointerOperand() utility.
LoopVectorize.cpp has one of them,
and I don't want to create a 7th one while I'm trying to move
LoopVectorizationLegality into a separate file
(eventual objective is to move it to Analysis tree).

See http://lists.llvm.org/pipermail/llvm-dev/2018-February/120999.html
for llvm-dev discussions

Closes D43323.

Patch by Hideki Saito <hideki.saito@intel.com>.

llvm-svn: 327173
2018-03-09 21:05:58 +00:00
Peter Collingbourne 2974856ad4 Use branch funnels for virtual calls when retpoline mitigation is enabled.
The retpoline mitigation for variant 2 of CVE-2017-5715 inhibits the
branch predictor, and as a result it can lead to a measurable loss of
performance. We can reduce the performance impact of retpolined virtual
calls by replacing them with a special construct known as a branch
funnel, which is an instruction sequence that implements virtual calls
to a set of known targets using a binary tree of direct branches. This
allows the processor to speculately execute valid implementations of the
virtual function without allowing for speculative execution of of calls
to arbitrary addresses.

This patch extends the whole-program devirtualization pass to replace
certain virtual calls with calls to branch funnels, which are
represented using a new llvm.icall.jumptable intrinsic. It also extends
the LowerTypeTests pass to recognize the new intrinsic, generate code
for the branch funnels (x86_64 only for now) and lay out virtual tables
as required for each branch funnel.

The implementation supports full LTO as well as ThinLTO, and extends the
ThinLTO summary format used for whole-program devirtualization to
support branch funnels.

For more details see RFC:
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120672.html

Differential Revision: https://reviews.llvm.org/D42453

llvm-svn: 327163
2018-03-09 19:11:44 +00:00
Chad Rosier 95d9ccb2a0 [JumpThreading] Don't restrict cast-traversal to i1
In r263618, JumpThreading learned to look trough simple cast instructions, but
only if the source of those cast instructions was a phi/cmp i1 (in an effort to
limit compile time effects). I think this condition is too restrictive. For
switches with limited value range, InstCombine will readily introduce an extra
trunc instruction to a smaller integer type (e.g. from i8 to i2), leaving us in
the somewhat perverse situation that jump-threading would work before running
instcombine, but not after. Since instcombine produces this pattern, I think we
need to consider it canonical and support it in JumpThreading.  In general,
for limiting recursion, I think the existing restriction to phi and cmp nodes
should be sufficient to avoid looking through unprofitable chains of
instructions.

Patch by Keno Fischer!
Differential Revision: https://reviews.llvm.org/D42262

llvm-svn: 327150
2018-03-09 16:43:46 +00:00
Renato Golin 6b62039bb0 [LV] Fix vectorizer's isUniform() abuse triggers assert in SCEV
Fixes PR36311.

See more detailed analysis in
https://bugs.llvm.org/show_bug.cgi?id=36311.

isUniform() information is recomputed after LV started transforming the
underlying IR and that triggered an assert in SCEV.

From vectorizer's architectural perspective, such information, while
still useful in vector code gen, should not be recomputed after the
start of transforming the LLVM IR. Instead, we should collect and cache
such information during the analysis phase of LV and use the cached info
during code gen.

From the symptom perspective, this assert as it stands right now is not
very useful. Legality already rejected loops that would trigger the
assert. As such, commenting out the assert is NFC from vectorizer's
functionality perspective. On top of that, just above the assertion, we
check for unit-strided load/store or
gather scatter. Addresses can't be uniform below that check.

From vectorization theory point of view, we don't have to reject all
cases of stores to uniform addresses. Eventually, we should support
safe/profitable cases.

This patch resolves the issue by removing the useless assertion that is
invoking LAA's isUniform() that requires up-to-date DomTree ---- once
vector code gen starts modifying CFG, we don't have an up-to-date
DomTree.

Patch by Hideki Saito <hideki.saito@intel.com>.

llvm-svn: 327109
2018-03-09 10:31:31 +00:00
Eric Christopher 3caa0fd050 Revert "[ThinLTO] Keep available_externally symbols live"
This reverts commit r327041 and the followup attempts at fixing the testcase as they're still failing.

llvm-svn: 327094
2018-03-09 01:25:18 +00:00
Adrian Prantl 5b477be72a LowerDbgDeclare: ignore dbg.declares for allocas with volatile access
There is no point in lowering a dbg.declare describing an alloca that
has volatile loads or stores as users, since the alloca cannot be
elided. Lowering the dbg.declare will result in larger debug info that
may also have worse coverage than just describing the alloca.

rdar://problem/34496278

llvm-svn: 327092
2018-03-09 00:45:04 +00:00
Philip Reames fbffd126b8 [NFC] Factor out a helper function for checking if a block has a potential early implicit exit.
llvm-svn: 327065
2018-03-08 21:25:30 +00:00
Kuba Mracek 8842da8e07 [asan] Fix a false positive ODR violation due to LTO ConstantMerge pass [llvm part, take 3]
This fixes a false positive ODR violation that is reported by ASan when using LTO. In cases, where two constant globals have the same value, LTO will merge them, which breaks ASan's ODR detection.

Differential Revision: https://reviews.llvm.org/D43959

llvm-svn: 327061
2018-03-08 21:02:18 +00:00
Kuba Mracek f0bcbfef5c Revert r327053.
llvm-svn: 327055
2018-03-08 20:13:39 +00:00
Kuba Mracek 584bd10803 [asan] Fix a false positive ODR violation due to LTO ConstantMerge pass [llvm part, take 2]
This fixes a false positive ODR violation that is reported by ASan when using LTO. In cases, where two constant globals have the same value, LTO will merge them, which breaks ASan's ODR detection.

Differential Revision: https://reviews.llvm.org/D43959

llvm-svn: 327053
2018-03-08 20:05:45 +00:00
Vlad Tsyrklevich 7b66ef1036 [ThinLTO] Keep available_externally symbols live
Summary:
This change fixes PR36483. The bug was originally introduced by a change
that marked non-prevailing symbols dead. This broke LowerTypeTests
handling of available_externally functions, which are non-prevailing.
LowerTypeTests uses liveness information to avoid emitting thunks for
unused functions.

Marking available_externally functions dead is incorrect, the functions
are used though the function definitions are not. This change keeps them
live, and lets the EliminateAvailableExternally/GlobalDCE passes remove
them later instead.

I've also enabled EliminateAvailableExternally for all optimization
levels, I believe it being disabled for O1 was an oversight.

Reviewers: pcc, tejohnson

Reviewed By: tejohnson

Subscribers: grimar, mehdi_amini, inglorion, eraman, llvm-commits

Differential Revision: https://reviews.llvm.org/D43690

llvm-svn: 327041
2018-03-08 18:48:03 +00:00
Kuba Mracek e834b22874 Revert r327029
llvm-svn: 327033
2018-03-08 17:32:00 +00:00
Kuba Mracek 0e06d37dba [asan] Fix a false positive ODR violation due to LTO ConstantMerge pass [llvm part]
This fixes a false positive ODR violation that is reported by ASan when using LTO. In cases, where two constant globals have the same value, LTO will merge them, which breaks ASan's ODR detection.

Differential Revision: https://reviews.llvm.org/D43959

llvm-svn: 327029
2018-03-08 17:24:06 +00:00
Farhana Aleen 89196642f7 [AMDGPU] Increased vector length for global/constant loads.
Summary: GCN ISA supports instructions that can read 16 consecutive dwords from memory through the scalar data cache;
         loadstoreVectorizer should take advantage of the wider vector length and pack 16/8 elements of dwords/quadwords.

Author: FarhanaAleen

Reviewed By: rampitec

Subscribers: llvm-commits, AMDGPU

Differential Revision: https://reviews.llvm.org/D44179

llvm-svn: 326910
2018-03-07 17:09:18 +00:00
Justin Lebar eccfbf1bcd Re-land: Teach CorrelatedValuePropagation to reduce the width of udiv/urem instructions.
Summary:
If the operands of a udiv/urem can be proved to fit within a smaller
power-of-two-sized type, reduce the width of the udiv/urem.

Backed out for failing an assert in clang bootstrap builds.  Re-landing
with a fix for handling non-power-of-two inputs (e.g. udiv i24).

Original Differential Revision: https://reviews.llvm.org/D44102

llvm-svn: 326908
2018-03-07 16:56:49 +00:00
Farhana Aleen 347d12b4ce Revert "[AMDGPU] Widened vector length for global/constant address space."
This reverts commit ce988cc100dc65e7c6c727aff31ceb99231cab03.

llvm-svn: 326907
2018-03-07 16:55:27 +00:00
Farhana Aleen 0d03d0588d [AMDGPU] Widened vector length for global/constant address space.
llvm-svn: 326904
2018-03-07 16:29:05 +00:00
Justin Lebar eeeb0eb049 Revert rL326898: "Teach CorrelatedValuePropagation to reduce the width of udiv/urem instructions."
Breaks bootstrap builds: clang built with this patch asserts while
building MCDwarf.cpp: Assertion `castIsValid(op, S, Ty) && "Invalid
cast!"' failed.

llvm-svn: 326900
2018-03-07 16:05:43 +00:00
Justin Lebar cb9e89c39b Teach CorrelatedValuePropagation to reduce the width of udiv/urem instructions.
Summary:
If the operands of a udiv/urem can be proved to fit within a smaller
power-of-two-sized type, reduce the width of the udiv/urem.

Reviewers: spatel, sanjoy

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D44102

llvm-svn: 326898
2018-03-07 15:11:13 +00:00
Sven van Haastregt 19f531d31e [LoadStoreVectorizer] Differentiate between <1 x T> and T
The LoadStoreVectorizer thought that <1 x T> and T were the same types
when merging stores, leading to a crash later.

Patch by Erik Hogeman.

Differential Revision: https://reviews.llvm.org/D44014

llvm-svn: 326884
2018-03-07 10:29:28 +00:00
Evgeny Stupachenko 204ade4102 Add early exit on reassociation of 0 expression.
Summary:

Before the patch a try to reassociate ((v * 16) * 0) * 1 fall into infinite loop

Reviewers: pankajchawla

Differential Revision: http://reviews.llvm.org/D41467

From: Evgeny Stupachenko <evstupac@gmail.com>
                         <evgeny.v.stupachenko@intel.com>
llvm-svn: 326861
2018-03-07 02:17:08 +00:00
Eugene Zelenko e2fc88a2fe [Transforms] Add missing header for InstructionCombining.cpp, in order to export LLVMInitializeInstCombine as extern "C". Fixes PR35947.
Patch by Brenton Bostick.

Differential revision: https://reviews.llvm.org/D44140

llvm-svn: 326843
2018-03-06 23:06:13 +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
Sanjay Patel 1f2f5d18d3 [InstCombine] simplify min/max canonicalization; NFCI
llvm-svn: 326828
2018-03-06 19:01:18 +00:00
Sanjay Patel 7ed0bc26ac [ValueTracking] move helpers for SelectPatterns from InstCombine to ValueTracking
Most of the folds based on SelectPatternResult belong in InstSimplify rather than
InstCombine, so the helper code should be available to other passes/analysis.

llvm-svn: 326812
2018-03-06 16:57:55 +00:00
Florian Hahn 517dc51c48 [CallSiteSplitting] Do not crash when BB's terminator changes.
Change doCallSiteSplitting to iterate until we reach the terminator instruction.
tryToSplitCallSite can replace BB's terminator in case BB is a successor of
itself. Then IE will be invalidated and we also have to check the current
terminator.

Reviewers: junbuml, davidxl, davide, fhahn

Reviewed By: fhahn, junbuml

Differential Revision: https://reviews.llvm.org/D43824

llvm-svn: 326793
2018-03-06 14:00:58 +00:00
Florian Hahn f0a25f7253 [CloneFunction] Support BB == PredBB in DuplicateInstructionsInSplit.
In case PredBB == BB and StopAt == BB's terminator, StopAt != &*BI will
fail, because BB's terminator instruction gets replaced.

By using BB.getTerminator() we get the current terminator which we can use
to compare.

Reviewers: sanjoy, anna, reames

Reviewed By: anna

Differential Revision: https://reviews.llvm.org/D43822

llvm-svn: 326779
2018-03-06 13:12:32 +00:00
Xin Tong 8fd561f572 [MergeICmp] Simplify how BCECmpBlock instructions are blacklisted
llvm-svn: 326761
2018-03-06 02:24:02 +00:00
Xin Tong 98af9efca5 [MergeICmp] Fix printing. NFC
llvm-svn: 326760
2018-03-06 02:04:57 +00:00
Daniel Neilson 82daad31fe [RewriteStatepoints] Fix stale parse points
Summary:
RewriteStatepointsForGC collects parse points for further processing.
During the collection if a callsite is found in an unreachable block
(DominatorTree::isReachableFromEntry()) then all unreachable blocks are
removed by removeUnreachableBlocks(). Some of the removed blocks could
have been reachable according to DominatorTree::isReachableFromEntry().
In this case the collected parse points became stale and resulted in a
crash when accessed.

The fix is to unconditionally canonicalize the IR to
removeUnreachableBlocks and then collect the parse points.

The added test crashes with the old version and passes with this patch.

Patch by Yevgeny Rouban!

Reviewed by: Anna

Differential Revision: https://reviews.llvm.org/D43929

llvm-svn: 326748
2018-03-05 22:27:30 +00:00
Daniel Neilson bdda115e19 [InstCombine] Don't blow up in foldICmpWithCastAndCast on vector icmp instructions.
Summary:
Presently, InstCombiner::foldICmpWithCastAndCast() implicitly assumes that it is
only invoked with icmp instructions of integer type. If that assumption is broken,
and it is called with an icmp of vector type, then it fails (asserts/crashes).

This patch addresses the deficiency. It allows it to simplify
icmp (ptrtoint x), (ptrtoint/c) of vector type into a compare of the inputs,
much as is done when the type is integer.

Reviewers: apilipenko, fedor.sergeev, mkazantsev, anna

Reviewed By: anna

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D44063

llvm-svn: 326730
2018-03-05 18:05:51 +00:00
Craig Topper 8452faceae [InstCombine] Add constant vector support to getMinimumFPType for visitFPTrunc.
This patch teaches getMinimumFPType to support shrinking a vector of ConstantFPs. This should improve our ability to combine vector fptrunc with fp binops.

Differential Revision: https://reviews.llvm.org/D43774

llvm-svn: 326729
2018-03-05 18:04:12 +00:00
Florian Hahn 0b7c6422fb [IPSCCP] Add getCompare which returns either true, false, undef or null.
getCompare returns true, false or undef constants if the comparison can
be evaluated, or nullptr if it cannot. This is in line with what
ConstantExpr::getCompare returns. It also allows us to use
ConstantExpr::getCompare for comparing constants.

Reviewers: davide, mssimpso, dberlin, anna

Reviewed By: davide

Differential Revision: https://reviews.llvm.org/D43761

llvm-svn: 326720
2018-03-05 17:33:50 +00:00
Sanjay Patel 53ffabdfcb [CVP] fix formatting; NFC
llvm-svn: 326711
2018-03-05 16:08:34 +00:00
Xin Tong 8345c0e3a5 [MergeICmp] We can discard initial blocks that do other work
Summary:
 We can discard initial blocks that do other work
We do not need to limit ourselves to just the first block in the chain.

Reviewers: courbet, davide

Reviewed By: courbet

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D44029

llvm-svn: 326698
2018-03-05 13:54:47 +00:00
Clement Courbet 34be1b0288 [MergeICmps][NFC] Improve logging.
llvm-svn: 326683
2018-03-05 08:21:47 +00:00
Fedor Indutny 364b9c2adb [CallSiteSplitting] fix use after-free
Iterating through predecessors of `TailBB` while removing their
terminators leads to use after-free, because the predecessor list is
changing on each removal.

llvm-svn: 326668
2018-03-03 22:34:38 +00:00
Fedor Indutny f9e09c1dd0 [CallSiteSplitting] properly split musttail calls
Summary:
`musttail` calls can't be naively splitted. The split blocks must
include not only the call instruction itself, but also (optional)
`bitcast` and `return` instructions that follow it.

Clone `bitcast` and `ret`, place them into the split blocks, and
remove the tail block when done.

Reviewers: junbuml, mcrosier, davidxl, davide, fhahn

Reviewed By: fhahn

Subscribers: JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D43729

llvm-svn: 326666
2018-03-03 21:40:14 +00:00
Sanjay Patel 1a8d5c3d1f [InstCombine] (~X) - (~Y) --> Y - X
llvm-svn: 326660
2018-03-03 17:53:25 +00:00
Chandler Carruth a4619d9944 [ThinLTO] Revert r325320: Import global variables
This caused some links to fail with ThinLTO due to missing symbols as
well as causing some binaries to have failures at runtime. We're working
with the author to get a test case, but want to get the tree green
again.

Further, it appears to introduce a data race. While the test usage of
threads was disabled in r325361 & r325362, that isn't an acceptable fix.
I've reverted both of these as well. This code needs to be thread safe.
Test cases for this are already on the original commit thread.

llvm-svn: 326638
2018-03-02 23:40:08 +00:00
Vedant Kumar 7fc591f8bb [AggressiveInstCombine] Use use_empty() instead of !getNumUses(), NFC
use_empty() runs in O(1), whereas getNumUses() runs in O(# uses).

llvm-svn: 326635
2018-03-02 23:22:49 +00:00
Sanjay Patel e29375d04c [InstCombine] rearrange visitFMul; NFCI
Put the simplest non-FMF folds first, so it's easier to
see what's left to fix/group/add with the FMF folds.

llvm-svn: 326632
2018-03-02 23:06:45 +00:00
Vedant Kumar f69baf64eb [Utils] Salvage debug info in block simplification
In stage2 -O3 builds of llc, this results in small but measurable
increases in the number of variables with locations, and in the number
of unique source variables overall.

(According to llvm-dwarfdump --statistics, there are 123 additional
variables with locations, which is just a 0.006% improvement).

The size of the .debug_loc section of the llc dsym increases by 0.004%.

llvm-svn: 326629
2018-03-02 22:46:48 +00:00
Vedant Kumar 334fa57456 [Utils] Salvage debug info in recursive inst deletion
In stage2 -O3 builds of llc, this results in a 0.3% increase in the
number of variables with locations, and a 0.2% increase in the number of
unique source variables overall.

The size of the .debug_loc section of the llc dsym increases by 0.5%.

llvm-svn: 326621
2018-03-02 21:36:35 +00:00
Craig Topper c7461e1aad [InstCombine] Rewrite the binary op shrinking in visitFPTrunc to avoid creating overly small ConstantFPs that we'll just need to extend again.
Instead of returning the smaller FP constant we now return the minimal Type the constant can fit into. We also return the Type of the input to any fp extends. The legality checks are then done on just the size of these Types. If we find something profitable we then emit FPTruncs in front of the smaller binop and assume those FPTruncs will be constant folded or combined with any ConstantFPs or fpextends.

Differential Revision: https://reviews.llvm.org/D44038

llvm-svn: 326617
2018-03-02 21:25:18 +00:00
Sanjay Patel 2fd0acf05a [InstCombine] partly fix FMF for fmul+log2 fold
The code was checking that all of the instructions in the 
sequence are 'fast', but that's not necessary. The final 
multiply is all that we need to check (tests adjusted). 
The fmul doesn't need to be fully 'fast' either, but that 
can be another patch.

llvm-svn: 326608
2018-03-02 20:32:46 +00:00
Yaxun Liu 3c42f1c3c9 LoopUnroll: respect pragma unroll when AllowRemainder is disabled
Currently when AllowRemainder is disabled, pragma unroll count is not
respected even though there is no remainder. This bug causes a loop
fully unrolled in many cases even though the user specifies a unroll
count. Especially it affects OpenCL/CUDA since in many cases a loop
contains convergent instructions and currently AllowRemainder is
disabled for such loops.

Differential Revision: https://reviews.llvm.org/D43826

llvm-svn: 326585
2018-03-02 16:22:32 +00:00
Florian Hahn 515acd64fd [LV][CFG] Add irreducible CFG detection for outer loops
This patch adds support for detecting outer loops with irreducible control
flow in LV. Current detection uses SCCs and only works for innermost loops.
This patch adds a utility function that works on any CFG, given its RPO
traversal and its LoopInfoBase. This function is a generalization
of isIrreducibleCFG  from lib/CodeGen/ShrinkWrap.cpp. The code in
lib/CodeGen/ShrinkWrap.cpp is also updated to use the new generic utility
function.

Patch by Diego Caballero <diego.caballero@intel.com>

Differential Revision: https://reviews.llvm.org/D40874

llvm-svn: 326568
2018-03-02 12:24:25 +00:00
Fedor Indutny 1571b1271e [ArgumentPromotion] don't break musttail invariant PR36543
Summary:
Do not break musttail invariant by promoting arguments of musttail
callee or caller.

Reviewers: sanjoy, dberlin, hfinkel, george.burgess.iv, fhahn, rnk

Reviewed By: rnk

Subscribers: rnk, llvm-commits

Differential Revision: https://reviews.llvm.org/D43926

llvm-svn: 326521
2018-03-02 00:59:27 +00:00
Sanjay Patel d0cdb2f861 [InstCombine] allow fmul fold with less than 'fast'
This is a retry of r326502 with updates to the reassociate 
test file that I missed the first time.

@test15_reassoc in the supposed -reassociate test file 
(except that it tests 2 other passes too...) shows that
there's no clear responsiblity for reassociation transforms.

Instcombine now gets that case, but only because the
constant values are identical. Otherwise, it would still
miss that pattern. 

Reassociate doesn't get that case because it hasn't been 
updated to use less than 'fast' FMF.

llvm-svn: 326513
2018-03-02 00:14:51 +00:00
Sanjay Patel eb5d046890 revert r326502: [InstCombine] allow fmul fold with less than 'fast'
I forgot that I added tests for 'reassoc' to -reassociate, but
suprisingly that file calls -instcombine too, so it is affected.
I'll update that file and try again.

llvm-svn: 326510
2018-03-01 23:39:24 +00:00
Sanjay Patel 7373ae5c9a [InstCombine] allow fmul fold with less than 'fast'
llvm-svn: 326502
2018-03-01 22:53:47 +00:00
Craig Topper 2915bc0046 [SimplifyLibCalls] Update an obviously copy and pasted header comment to match this file. NFC
llvm-svn: 326475
2018-03-01 20:05:09 +00:00
Sanjay Patel f3b1af7aa4 [InstCombine] simplify code for (X*Y) * X => (X*X) * Y ; NFCI
llvm-svn: 326444
2018-03-01 15:50:26 +00:00
Benjamin Kramer d1cf7ff5ab [SCCP] Fix unused variable warning in release builds.
llvm-svn: 326429
2018-03-01 11:31:44 +00:00
Reid Kleckner 3762a089d7 [IPSCCP] do not break musttail invariant (PR36485)
Do not replace results of `musttail` calls with a constant if the
call itself can't be removed.

Do not zap returns of `musttail` callees, if the call site can't be
removed and replaced with a constant.

Do not zap returns of `musttail`-calling blocks, this breaks
invariant too.

Patch by Fedor Indutny

Differential Revision: https://reviews.llvm.org/D43695

llvm-svn: 326404
2018-03-01 01:19:18 +00:00
Reid Kleckner cb9611ca67 [DAE] don't remove args of musttail target/caller
`musttail` requires identical signatures of caller and callee. Removing
arguments breaks `musttail` semantics.

PR36441

Patch by Fedor Indutny

Differential Revision: https://reviews.llvm.org/D43708

llvm-svn: 326394
2018-03-01 00:09:35 +00:00
Sanjay Patel eaf5a120ed [InstCombine] simplify code for X * -1.0 --> -X; NFC
I've added random FMF to one of the tests to show those are propagated.

llvm-svn: 326377
2018-02-28 22:30:04 +00:00
Jonas Devlieghere 9ca064552a [GlobalOpt] don't change CC of musttail calle(e|r)
When the function has musttail call - its cc is fixed to be equal to the
cc of the musttail callee. In such case (and in the case of the musttail
callee), GlobalOpt should not change the cc to fastcc as it will break
the invariant.

This fixes PR36546

Patch by: Fedor Indutny (indutny)

Differential revision: https://reviews.llvm.org/D43859

llvm-svn: 326376
2018-02-28 22:28:44 +00:00
Craig Topper b95298b041 [InstCombine] Split the FP constant code out of lookThroughFPExtensions and use nullptr as a sentinel
Currently this code's control flow very much assumes that there are no meaningful checks after determining that it's a ConstantFP. So whenever it wants to stop it just does "return V". But V is also the variable name it uses when it wants to return a new value. So 'return V' appears multiple times with different meanings.

This patch just moves all the code into a helper function and returns nullptr when it wants to stop.

I've split this from D43774 while I try to figure out how to best handle the vector case there. But this change by itself at least seemed like a readability improvement.

Differential Revision: https://reviews.llvm.org/D43833

llvm-svn: 326361
2018-02-28 20:14:34 +00:00
Vedant Kumar 9a041a7522 [InstrProfiling] Emit the runtime hook when no counters are lowered
The API verification tool tapi has difficulty processing frameworks
which enable code coverage, but which have no code. The profile lowering
pass does not emit the runtime hook in this case because no counters are
lowered.

While the hook is not needed for program correctness (the profile
runtime doesn't have to be linked in), it's needed to allow tapi to
validate the exported symbol set of instrumented binaries.

It was not possible to add a workaround in tapi for empty binaries due
to an architectural issue: tapi generates its expected symbol set before
it inspects a binary. Changing that model has a higher cost than simply
forcing llvm to always emit the runtime hook.

rdar://36076904

Differential Revision: https://reviews.llvm.org/D43794

llvm-svn: 326350
2018-02-28 19:00:08 +00:00
Sanjay Patel b3f4f62698 [InstCombine] move invariant call out of loop; NFC
We really shouldn't need a 2-loop here at all, but that's another cleanup.

llvm-svn: 326330
2018-02-28 16:50:51 +00:00
Sanjay Patel 8fdd87f929 [InstCombine] move constant check into foldBinOpIntoSelectOrPhi; NFCI
Also, rename 'foldOpWithConstantIntoOperand' because that's annoyingly 
vague. The constant check is redundant in some cases, but it allows 
removing duplication for most of the calls.

llvm-svn: 326329
2018-02-28 16:36:24 +00:00
Xin Tong 256869d8bc Fix typo. NFC
llvm-svn: 326319
2018-02-28 12:09:53 +00:00
Xin Tong 8ba674e43b [MergeICmp] Fix a bug in MergeICmp that can lead to a block being processed more than once.
Summary:
Fix a bug in MergeICmp that can lead to a BCECmp block being processed more than once and eventually lead to a broken LLVM module.
The problem is that if the non-constant value is not produced by the last block, the producer will be processed once when the its parent block
is processed and second time when the last block is processed.

We end up having 2 same BCECmpBlock in the merge queue. And eventually lead to a broken LLVM module.

Reviewers: courbet, davide

Reviewed By: courbet

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D43825

llvm-svn: 326318
2018-02-28 12:08:00 +00:00
David Green 7c35de124a [Dominators] Remove verifyDomTree and add some verifying for Post Dom Trees
Removes verifyDomTree, using assert(verify()) everywhere instead, and
changes verify a little to always run IsSameAsFreshTree first in order
to print good output when we find errors. Also adds verifyAnalysis for
PostDomTrees, which will allow checking of PostDomTrees it the same way
we check DomTrees and MachineDomTrees.

Differential Revision: https://reviews.llvm.org/D41298

llvm-svn: 326315
2018-02-28 11:00:08 +00:00
Florian Hahn 1807c516c7 [NewGVN] Update phi-of-ops def block when updating existing ValuePHI.
In case we update a ValuePHI node created earlier, we could update it
based on a different OpPHI which could be in a different block.
We need to update the TempToBlock mapping reflecting the new block,
otherwise we would end up placing the new phi node in a wrong block.

This problem is exposed by the test case in
https://bugs.llvm.org/show_bug.cgi?id=36504.

This patch fixes a slightly simpler problem than in the bug report. In
the bug's re-producer, the additional problem is that we are re-using a
ValuePHI node with to few incoming values for the new OpPHI. If this
patch makes sense, I will follow it up with a patch that creates a new
PHI node if the existing PHI node has a different number of incoming
values.

Reviewers: davide, dberlin

Reviewed By: dberlin

Differential Revision: https://reviews.llvm.org/D43770

llvm-svn: 326181
2018-02-27 09:34:51 +00:00
Sanjay Patel 31a90468e1 [InstCombine] allow fdiv folds with less than fully 'fast' ops
Note: gcc appears to allow this fold with -freciprocal-math alone, 
but clang/llvm require more than that with this patch. The wording
in the definitions seems fuzzy enough that it could go either way,
but we'll err on the conservative side of FMF interpretation.

This patch also changes the newly created fmul to have FMF propagated
by the last fdiv rather than intersecting the FMF of the fdivs. This
matches the behavior of other folds near here. The new fmul is only 
used to produce an intermediate op for the final fdiv result, so it
shouldn't be any stricter than that result. The previous behavior
could result in dropping FMF via other folds in instcombine or CSE.

Differential Revision: https://reviews.llvm.org/D43398

llvm-svn: 326098
2018-02-26 16:02:45 +00:00
Renato Golin 9d1b2acaaa [LV] Move isLegalMasked* functions from Legality to CostModel
All SIMD architectures can emulate masked load/store/gather/scatter
through element-wise condition check, scalar load/store, and
insert/extract. Therefore, bailing out of vectorization as legality
failure, when they return false, is incorrect. We should proceed to cost
model and determine profitability.

This patch is to address the vectorizer's architectural limitation
described above. As such, I tried to keep the cost model and
vectorize/don't-vectorize behavior nearly unchanged. Cost model tuning
should be done separately.

Please see
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120164.html for
RFC and the discussions.

Closes D43208.

Patch by: Hideki Saito <hideki.saito@intel.com>

llvm-svn: 326079
2018-02-26 11:06:36 +00:00
Florian Hahn a1822cbabc [LoopInterchange] Loops with empty dependency matrix are safe.
The dependency matrix is only empty if no conflicting load/store
instructions have been found. In that case, it is safe to interchange.

For the LLVM test-suite, after this change around 1900 loops are
interchanged, whereas it is 15 before this change. On cortex-a57,
this gives an improvement of -0.57% on the geomean execution
time of SPEC2006, SPEC2000 and the test-suite. There are a
few small perf regressions, but I think we can improve on those
by making the cost model better.

Reviewers: karthikthecool, mcrosier

Reviewed by: karthikthecool

Differential Revision: https://reviews.llvm.org/D43236

llvm-svn: 326077
2018-02-26 10:45:25 +00:00
Adam Nemet e4e1de60aa Revert "StructurizeCFG: Test for branch divergence correctly"
This reverts commit r325881.

Breaks many bots

llvm-svn: 326037
2018-02-24 17:29:09 +00:00
Sanjay Patel 2db2769499 [InstCombine] simplify code for fabs(X) * fabs(X) -> X * X; NFC
llvm-svn: 325968
2018-02-23 22:38:10 +00:00
Sanjay Patel db53d1847b [InstSimplify] sqrt(X) * sqrt(X) --> X
This was misplaced in InstCombine. We can loosen the FMF as a follow-up step.

llvm-svn: 325965
2018-02-23 22:20:13 +00:00
Sanjay Patel d32104e1b2 [InstCombine] allow fmul-sqrt folds with less than full -ffast-math
Also, add a Builder method for intrinsics to reduce code duplication for clients.

llvm-svn: 325960
2018-02-23 21:16:12 +00:00
Matt Davis 523c656e25 [Debug] Add dbg.value intrinsics for PHIs created during LCSSA.
Summary:
This patch is an enhancement to propagate dbg.value information when Phis are created on behalf of LCSSA.
I noticed a case where a value carried across a loop was reported as <optimized out>.

Specifically this case:
```
int bar(int x, int y) {
  return x + y;
}

int foo(int size) {
  int val = 0;
  for (int i = 0; i < size; ++i) {
    val = bar(val, i);  // Both val and i are correct
  }
  return val; // <optimized out>
}
```

In the above case, after all of the interesting computation completes our value
is reported as "optimized out." This change will add a dbg.value to correct this.

This patch also moves the dbg.value insertion routine from LoopRotation.cpp 
into Local.cpp, so that we can share it in both places (LoopRotation and LCSSA).

Reviewers: mzolotukhin, aprantl, vsk, davide

Reviewed By: aprantl, vsk

Subscribers: dberlin, llvm-commits

Differential Revision: https://reviews.llvm.org/D42551

llvm-svn: 325926
2018-02-23 17:38:27 +00:00
Sanjay Patel 6b9c7a9c83 [InstCombine] refactor fmul with negated op folds; NFCI
The existing code was inefficiently looking for 'nsz' variants.
That's unnecessary because we canonicalize those to the expected
form with -0.0.

We may also want to adjust or remove the fold that sinks negation.
We don't do that for fdiv (or integer ops?). That should be uniform?
It may also lead to missed optimization as in PR21914:
https://bugs.llvm.org/show_bug.cgi?id=21914
...or we just have to fix other passes to avoid that problem.

llvm-svn: 325924
2018-02-23 17:14:28 +00:00
Sanjay Patel 4a9116e897 [InstCombine] use FMF-copying functions to reduce code; NFCI
llvm-svn: 325923
2018-02-23 17:07:29 +00:00
Nicolai Haehnle 43c1115cd4 StructurizeCFG: Test for branch divergence correctly
Summary:
This fixes cases like the new test @nonuniform. In that test, %cc itself
is a uniform value; however, when reading it after the end of the loop in
basic block %if, its value is effectively non-uniform.

This problem was encountered in
https://bugs.freedesktop.org/show_bug.cgi?id=103743; however, this change
in itself is not sufficient to fix that bug, as there is another issue
in the AMDGPU backend.

Change-Id: I32bbffece4a32f686fab54964dae1a5dd72949d4

Reviewers: arsenm, rampitec, jlebar

Subscribers: wdng, tpr, llvm-commits

Differential Revision: https://reviews.llvm.org/D40546

llvm-svn: 325881
2018-02-23 10:45:46 +00:00
Bjorn Steinbrink 983d6c3f18 Mark MergedLoadStoreMotion as not preserving MemDep results
Summary:
MemDep caches results that signify that a dependence is non-local, and
there is currently no way to invalidate such cache entries.
Unfortunately, when MLSM sinks a store that can result in a non-local
dependence becoming a local one, and then MemDep gives wrong answers.
The easiest way out here is to just say that MLSM does indeed not
preserve MemDep results.

Reviewers: davide, Gerolf

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D43177

llvm-svn: 325880
2018-02-23 10:41:57 +00:00
Eric Christopher 675dcf02a8 Update comment for whether or not we can optimize an alias - we're
checking the alias and not the aliasee. If the alias can be interposed
then we shouldn't do anything.

llvm-svn: 325837
2018-02-22 23:12:11 +00:00
Peter Collingbourne 32f5405bff Fix DataFlowSanitizer instrumentation pass to take parameter position changes into account for custom functions.
When DataFlowSanitizer transforms a call to a custom function, the
new call has extra parameters. The attributes on parameters must be
updated to take the new position of each parameter into account.

Patch by Sam Kerner!

Differential Revision: https://reviews.llvm.org/D43132

llvm-svn: 325820
2018-02-22 19:09:07 +00:00
Daniel Neilson 20c9207be3 [AlignmentFromAssumptions] Set source and dest alignments of memory intrinsiscs separately
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
AlignmentFromAssumptions pass to cease using the old getAlignment()/setAlignment API of
MemoryIntrinsic in favour of getting/setting source & dest specific alignments through
the new API. This allows us to simplify some of the code in this pass and also be more
aggressive about setting the source and destination alignments separately.

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. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395, rL324402, rL324626, rL324642, rL324653, rL324654, rL324773, rL324774,
rL324781, rL324784, rL324955, rL324960 )
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

Reviewers: hfinkel, bollu, reames

Reviewed By: reames

Subscribers: reames, llvm-commits

Differential Revision: https://reviews.llvm.org/D43081

llvm-svn: 325816
2018-02-22 18:55:59 +00:00
Luke Cheeseman 6c1e6bbe0c [FunctionAttrs][ArgumentPromotion][GlobalOpt] Disable some optimisations passes for naked functions
- Fix for bug 36078.
- Prevent the functionattrs, function-attrs, globalopt and argpromotion passes
  from changing naked functions.
- These passes can perform some alterations to the functions that should not be
  applied. An example is removing parameters that are seemingly not used because
  they are only referenced in the inline assembly. Another example is marking
  the function as fastcc.

llvm-svn: 325788
2018-02-22 14:42:08 +00:00
Mircea Trofin 56950974d4 [SampleProf] NFC. Expose reusable functionality in SampleProfile.
Summary:
Exposing getOffset and findFunctionSamples as members of
SampleProfile. They are intimately tied to design choices of the
sample profile format - using offsets instead of line numbers, and
traversing inlined functions stack, respectively.

Reviewers: davidxl

Reviewed By: davidxl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D43605

llvm-svn: 325747
2018-02-22 06:42:57 +00:00
Vedant Kumar 1ceabcf080 [Utils] Avoid a hash table lookup in salvageDI, NFC
According to the current coverage report salvageDebugInfo() is called
5.12 million times during testing and almost always returns early.

The early return depends on LocalAsMetadata::getIfExists returning null,
which involves a DenseMap lookup in an LLVMContextImpl. We can probably
speed this up by simply checking the IsUsedByMD bit in Value.

llvm-svn: 325738
2018-02-22 01:29:41 +00:00
Sanjay Patel 5a6f904520 [InstCombine] add and use Create*FMF functions; NFC
llvm-svn: 325730
2018-02-21 22:18:55 +00:00
Evgeniy Stepanov 43271b1803 [hwasan] Fix inline instrumentation.
This patch changes hwasan inline instrumentation:

Fixes address untagging for shadow address calculation (use 0xFF instead of 0x00 for the top byte).
Emits brk instruction instead of hlt for the kernel and user space.
Use 0x900 instead of 0x100 for brk immediate (0x100 - 0x800 are unavailable in the kernel).
Fixes and adds appropriate tests.

Patch by Andrey Konovalov.

Differential Revision: https://reviews.llvm.org/D43135

llvm-svn: 325711
2018-02-21 19:52:23 +00:00
Vedant Kumar 56492f9177 [BDCE] Salvage debug info from dying insts
This results in 15 additional unique source variables in a stage2 build
of FileCheck (at '-Os -g'), with a negligible increase in the size of
the .debug_loc section.

llvm-svn: 325660
2018-02-21 01:55:33 +00:00
Sanjay Patel 6f716a7c5e [InstCombine] C / -X --> -C / X
We already do this in DAGCombiner, but it should
also be good to eliminate the fsub use in IR.

This is similar to rL325648.

llvm-svn: 325649
2018-02-21 00:01:45 +00:00