llvm-project

History

Alina Sbirlea fcfa7c5f92 [MemorySSA] Make insertDef insert corresponding phi nodes. Summary: The original assumption for the insertDef method was that it would not materialize Defs out of no-where, hence it will not insert phis needed after inserting a Def. However, when cloning an instruction (use case used in LICM), we do materialize Defs "out of no-where". If the block receiving a Def has at least one other Def, then no processing is needed. If the block just received its first Def, we must check where Phi placement is needed. The only new usage of insertDef is in LICM, hence the trigger for the bug. But the original goal of the method also fails to apply for the move() method. If we move a Def from the entry point of a diamond to either the left or right blocks, then the merge block must add a phi. While this usecase does not currently occur, or may be viewed as an incorrect transformation, MSSA must behave corectly given the scenario. Resolves PR40749 and PR40754. Reviewers: george.burgess.iv Subscribers: sanjoy, jlebar, Prazek, jdoerfert, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D58652 llvm-svn: 355040		2019-02-27 22:20:22 +00:00
..
AliasAnalysis.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
AliasAnalysisEvaluator.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
AliasAnalysisSummary.cpp	Move CFLGraph and the AA summary code over to the new `CallBase`	2019-02-11 09:25:41 +00:00
AliasAnalysisSummary.h	Move CFLGraph and the AA summary code over to the new `CallBase`	2019-02-11 09:25:41 +00:00
AliasSetTracker.cpp	[LICM/MSSA] Add promotion to scalars by building an AliasSetTracker with MemorySSA.	2019-02-06 20:25:17 +00:00
Analysis.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
AssumptionCache.cpp	[CodeExtractor] Update function's assumption cache after extracting blocks from it	2019-02-08 06:55:18 +00:00
BasicAliasAnalysis.cpp	[BasicAA] Cache nonEscapingLocalObjects for alias() calls.	2019-02-05 23:52:08 +00:00
BlockFrequencyInfo.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
BlockFrequencyInfoImpl.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
BranchProbabilityInfo.cpp	[BPI] Look through bitcasts in calcZeroHeuristic	2019-02-15 11:50:21 +00:00
CFG.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CFGPrinter.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CFLAndersAliasAnalysis.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CFLGraph.h	Move CFLGraph and the AA summary code over to the new `CallBase`	2019-02-11 09:25:41 +00:00
CFLSteensAliasAnalysis.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGSCCPassManager.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CMakeLists.txt	Move DomTreeUpdater from IR to Analysis	2019-02-06 02:52:52 +00:00
CallGraph.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CallGraphSCCPass.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CallPrinter.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CaptureTracking.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CmpInstAnalysis.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CodeMetrics.cpp	Remove `CallSite` from the CodeMetrics analysis, moving it to the new	2019-02-11 09:03:32 +00:00
ConstantFolding.cpp	[CallSite removal] Migrate ConstantFolding APIs and implementation to	2019-02-11 07:51:44 +00:00
CostModel.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
Delinearization.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
DemandedBits.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
DependenceAnalysis.cpp	[DA][NewPM] Handle transitive dependencies in the new-pm version of DA	2019-02-03 12:25:41 +00:00
DivergenceAnalysis.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
DomPrinter.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
DomTreeUpdater.cpp	[DTU] Refine the interface and logic of applyUpdates	2019-02-22 13:48:38 +00:00
DominanceFrontier.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
EHPersonalities.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
GlobalsModRef.cpp	[NFC] fix trivial typos in comments	2019-02-05 08:30:48 +00:00
GuardUtils.cpp	[NFC] Add function to parse widenable conditional branches	2019-01-22 11:21:32 +00:00
IVDescriptors.cpp	Move DomTreeUpdater from IR to Analysis	2019-02-06 02:52:52 +00:00
IVUsers.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
IndirectCallPromotionAnalysis.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
InlineCost.cpp	Revert "[INLINER] allow inlining of address taken blocks"	2019-02-14 23:42:21 +00:00
InstCount.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
InstructionPrecedenceTracking.cpp	Make widenable condition transparent for MemoryWriteTracking	2019-02-14 11:10:29 +00:00
InstructionSimplify.cpp	[InstSimplify] remove zero-shift-guard fold for general funnel shift	2019-02-26 18:26:56 +00:00
Interval.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
IntervalPartition.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
IteratedDominanceFrontier.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
LLVMBuild.txt	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
LazyBlockFrequencyInfo.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
LazyBranchProbabilityInfo.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
LazyCallGraph.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
LazyValueInfo.cpp	[NFC] fix trivial typos in comments	2019-02-05 08:30:48 +00:00
LegacyDivergenceAnalysis.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
Lint.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
Loads.cpp	[Analysis] Fix isSafeToLoadUnconditionally handling of volatile.	2019-01-24 21:31:13 +00:00
LoopAccessAnalysis.cpp	[NFC] fix trivial typos in comments	2019-02-05 08:30:48 +00:00
LoopAnalysisManager.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
LoopInfo.cpp	Refactor setAlreadyUnrolled() and setAlreadyVectorized().	2019-02-11 19:45:44 +00:00
LoopPass.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
LoopUnrollAnalyzer.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
MemDepPrinter.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
MemDerefPrinter.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
MemoryBuiltins.cpp	Add a 'dynamic' parameter to the objectsize intrinsic	2019-01-30 20:34:35 +00:00
MemoryDependenceAnalysis.cpp	[NFC] Fix typos: preceeding -> preceding	2019-02-23 01:28:32 +00:00
MemoryLocation.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
MemorySSA.cpp	[MemorySSA] Remove verifyClobberSanity.	2019-02-11 19:51:21 +00:00
MemorySSAUpdater.cpp	[MemorySSA] Make insertDef insert corresponding phi nodes.	2019-02-27 22:20:22 +00:00
ModuleDebugInfoPrinter.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ModuleSummaryAnalysis.cpp	[ThinLTO] Add option to dump per-module summary dot graph	2019-01-28 23:43:26 +00:00
MustExecute.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ObjCARCAliasAnalysis.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ObjCARCAnalysisUtils.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ObjCARCInstKind.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
OptimizationRemarkEmitter.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
OrderedBasicBlock.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
OrderedInstructions.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
PHITransAddr.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
PhiValues.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
PostDominators.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ProfileSummaryInfo.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
PtrUseVisitor.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
README.txt	…
RegionInfo.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
RegionPass.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
RegionPrinter.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ScalarEvolution.cpp	[NFC] Simplify code & reduce nest slightly	2019-02-12 11:31:46 +00:00
ScalarEvolutionAliasAnalysis.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ScalarEvolutionExpander.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ScalarEvolutionNormalization.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ScopedNoAliasAA.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
StackSafetyAnalysis.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
StratifiedSets.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SyncDependenceAnalysis.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SyntheticCountsUtils.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
TargetLibraryInfo.cpp	[TargetLibraryInfo] Update run time support for Windows	2019-02-11 22:12:01 +00:00
TargetTransformInfo.cpp	[LSR] Generate cross iteration indexes	2019-02-07 13:32:54 +00:00
Trace.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
TypeBasedAliasAnalysis.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
TypeMetadataUtils.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ValueLattice.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ValueLatticeUtils.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ValueTracking.cpp	Teach isGuaranteedToTransferExecutionToSuccessor about widenable conditions	2019-02-14 11:10:21 +00:00
VectorUtils.cpp	[Vectorizer] Add vectorization support for fixed smul/umul intrinsics	2019-02-25 15:42:02 +00:00

README.txt

Analysis Opportunities:

//===---------------------------------------------------------------------===//

In test/Transforms/LoopStrengthReduce/quadradic-exit-value.ll, the
ScalarEvolution expression for %r is this:

  {1,+,3,+,2}<loop>

Outside the loop, this could be evaluated simply as (%n * %n), however
ScalarEvolution currently evaluates it as

  (-2 + (2 * (trunc i65 (((zext i64 (-2 + %n) to i65) * (zext i64 (-1 + %n) to i65)) /u 2) to i64)) + (3 * %n))

In addition to being much more complicated, it involves i65 arithmetic,
which is very inefficient when expanded into code.

//===---------------------------------------------------------------------===//

In formatValue in test/CodeGen/X86/lsr-delayed-fold.ll,

ScalarEvolution is forming this expression:

((trunc i64 (-1 * %arg5) to i32) + (trunc i64 %arg5 to i32) + (-1 * (trunc i64 undef to i32)))

This could be folded to

(-1 * (trunc i64 undef to i32))

//===---------------------------------------------------------------------===//