Max Kazantsev d565552917 [IndVars] Fix usage of SCEVExpander to not mess with SCEVConstant. PR38674 ... This patch removes the function `expandSCEVIfNeeded` which behaves not as it was intended. This function tries to make a lookup for exact existing expansion and only goes to normal expansion via `expandCodeFor` if this lookup hasn't found anything. As a result of this, if some instruction above the loop has a `SCEVConstant` SCEV, this logic will return this instruction when asked for this `SCEVConstant` rather than return a constant value. This is both non-profitable and in some cases leads to breach of LCSSA form (as in PR38674). Whether or not it is possible to break LCSSA with this algorithm and with some non-constant SCEVs is still in question, this is still being investigated. I wasn't able to construct such a test so far, so maybe this situation is impossible. If it is, it will go as a separate fix. Rather than do it, it is always correct to just invoke `expandCodeFor` unconditionally: it behaves smarter about insertion points, and as side effect of this it will choose a constant value for SCEVConstants. For other SCEVs it may end up finding a better insertion point. So it should not be worse in any case. NOTE: So far the only known case for which this transform may break LCSSA is mapping of SCEVConstant to an instruction. However there is a suspicion that the entire algorithm can compromise LCSSA form for other cases as well (yet not proved). Differential Revision: https://reviews.llvm.org/D51286 Reviewed By: etherzhhb llvm-svn: 341345		2018-09-04 05:01:35 +00:00
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ADCE
AddDiscriminators
AggressiveInstCombine
AlignmentFromAssumptions
ArgumentPromotion
AtomicExpand	[AtomicExpandPass] Widen partword atomicrmw or/xor/and before tryExpandAtomicRMW	2018-08-17 14:03:37 +00:00
BDCE
BlockExtractor
BranchFolding
CalledValuePropagation
CallSiteSplitting
CodeExtractor	[CodeExtractor] Use 'normal destination' BB as insert point to store invoke results.	2018-08-21 20:07:46 +00:00
CodeGenPrepare	[ARM] Enable GEP offset splitting for 32-bit ARM.	2018-08-30 22:18:27 +00:00
ConstantHoisting	[Constant Hoisting] Hoisting Constant GEP Expressions	2018-09-01 00:04:56 +00:00
ConstantMerge
ConstProp	[X86] Add constant folding for AVX512 versions of scalar floating point to integer conversion intrinsics.	2018-08-12 22:09:54 +00:00
Coroutines
CorrelatedValuePropagation	[CVP] Extend tests to illustrate an old patch isn't needed	2018-08-24 21:56:43 +00:00
CrossDSOCFI
DCE
DeadArgElim
DeadStoreElimination	[BasicAA] Don't assume tail calls with byval don't alias allocas	2018-08-14 01:24:35 +00:00
DivRemPairs
EarlyCSE	[AMDGPU] Add support for multi-dword s.buffer.load intrinsic	2018-08-25 14:53:17 +00:00
EliminateAvailableExternally
EntryExitInstrumenter
ExpandMemCmp/X86
Float2Int
ForcedFunctionAttrs
FunctionAttrs	llvm: Add support for "-fno-delete-null-pointer-checks"	2018-07-09 22:27:23 +00:00
FunctionImport	Restore "[ThinLTO] Ensure we always select the same function copy to import"	2018-07-16 15:30:27 +00:00
GCOVProfiling
GlobalDCE
GlobalMerge	[GlobalMerge] Allow merging globals with explicit section markings.	2018-08-02 23:54:16 +00:00
GlobalOpt	[PPC] Remove Darwin support from POWER backend.	2018-08-28 01:18:29 +00:00
GlobalSplit
GuardWidening	[GuardWidening] Ignore guards with trivial conditions	2018-08-22 02:40:49 +00:00
GVN	[GVN] Invalidate cached info for phis when setting dead predecessors to undef	2018-08-23 12:48:17 +00:00
GVNHoist	[Local] Make DoesKMove required for combineMetadata.	2018-08-24 11:40:04 +00:00
GVNSink	[Local] Make DoesKMove required for combineMetadata.	2018-08-24 11:40:04 +00:00
IndirectBrExpand
IndVarSimplify	[IndVars] Fix usage of SCEVExpander to not mess with SCEVConstant. PR38674	2018-09-04 05:01:35 +00:00
InferAddressSpaces
InferFunctionAttrs	[LibCalls] Added returned attribute to libcalls	2018-08-23 05:18:23 +00:00
Inline	[Inliner] Attribute callsites with inline remarks	2018-08-28 15:27:25 +00:00
InstCombine	[InstCombine] allow add+not --> sub for arbitrary vector constants.	2018-09-03 18:21:59 +00:00
InstMerge
InstNamer
InstSimplify	[InstSimplify] use isKnownNeverNaN to fold more fcmp ord/uno	2018-08-21 14:45:13 +00:00
InterleavedAccess
Internalize
IPConstantProp	Recommit r333268: [IPSCCP] Use PredicateInfo to propagate facts from cmp instructions.	2018-08-23 11:04:00 +00:00
IRCE	Revert "[SCEV][NFC] Check NoWrap flags before lexicographical comparison of SCEVs"	2018-08-27 21:41:37 +00:00
JumpThreading	[Local] Make DoesKMove required for combineMetadata.	2018-08-24 11:40:04 +00:00
LCSSA	[DebugInfo][LCSSA] Preserve debug location in lcssa phis	2018-07-31 14:54:52 +00:00
LICM	Add a todo and tests to Address a review commnt from D50925 [NFC]	2018-08-29 22:09:21 +00:00
LoadStoreVectorizer	Revert "[SCEV][NFC] Check NoWrap flags before lexicographical comparison of SCEVs"	2018-08-27 21:41:37 +00:00
LoopDataPrefetch
LoopDeletion
LoopDistribute
LoopIdiom	SCEV should forget all loops containing a deleted block.	2018-08-09 17:53:26 +00:00
LoopInstSimplify	Update MemorySSA in LoopInstSimplify.	2018-08-22 20:05:21 +00:00
LoopInterchange	NFC - Various typo fixes in tests	2018-07-04 13:28:39 +00:00
LoopLoadElim
LoopPredication
LoopReroll	[LoopReroll] Rewrite induction variable rewriting.	2018-06-22 22:58:55 +00:00
LoopRotate	[ADCE] Remove the need of DomTree	2018-08-04 02:50:12 +00:00
LoopSimplify
LoopSimplifyCFG	Update MemorySSA in LoopSimplifyCFG.	2018-08-22 20:10:21 +00:00
LoopStrengthReduce	SCEVExpander::expandAddRecExprLiterally(): check before casting as Instruction	2018-06-29 07:44:20 +00:00
LoopUnroll	[X86] Make Feature64Bit useful	2018-08-30 06:01:05 +00:00
LoopUnrollAndJam	[UnJ] Improve explicit loop count checks	2018-08-11 07:37:31 +00:00
LoopUnswitch	[LoopUnswitch] Fix SCEV invalidation in unswitching	2018-05-23 10:09:53 +00:00
LoopVectorize	Revert "[SCEV][NFC] Check NoWrap flags before lexicographical comparison of SCEVs"	2018-08-27 21:41:37 +00:00
LoopVersioning	Re-apply "[SCEV] Strengthen StrengthenNoWrapFlags (reapply r334428)."	2018-07-13 23:58:46 +00:00
LoopVersioningLICM
LowerAtomic
LowerExpectIntrinsic
LowerGuardIntrinsic
LowerInvoke
LowerSwitch
LowerTypeTests	[LowerTypeTests] Limit when icall jumptable entries are emitted	2018-07-13 19:57:39 +00:00
Mem2Reg	Improve ConvertDebugDeclareToDebugValue	2018-06-26 06:17:00 +00:00
MemCpyOpt
MergeFunc
MergeICmps	[MergeICmps] Don't crash when memcmp is not available	2018-05-19 12:51:59 +00:00
MetaRenamer
NameAnonGlobals
NaryReassociate	[NaryReassociate] Detect deleted instr with WeakVH	2018-05-24 06:09:02 +00:00
NewGVN	[NewGVN] Add tests for r340031.	2018-08-17 14:39:53 +00:00
ObjCARC
PartiallyInlineLibCalls
PGOProfile	[PGO] add target md5sum in warning message for icall	2018-08-24 21:38:24 +00:00
PhaseOrdering
PlaceSafepoints
PreISelIntrinsicLowering
PruneEH
Reassociate	[Reassociate] swap binop operands to increase factoring potential	2018-09-02 14:22:54 +00:00
Reg2Mem
RewriteStatepointsForGC	NFC - Various typo fixes in tests	2018-07-04 13:28:39 +00:00
SafeStack	SafeStack: Prevent OOB reads with mem intrinsics	2018-08-30 20:44:51 +00:00
SampleProfile	[SampleFDO] Fix a bug in getOrCompHotCountThreshold/getOrCompColdCountThreshold	2018-08-07 18:13:10 +00:00
Scalarizer
SCCP	[PPC] Remove Darwin support from POWER backend.	2018-08-28 01:18:29 +00:00
SeparateConstOffsetFromGEP
SimpleLoopUnswitch	[SimpleLoopUnswitch] After unswitch delete dead blocks in parent loops	2018-08-29 19:10:44 +00:00
SimplifyCFG	[SimplifyCFG] Fix a cost modeling oversight in branch commoning	2018-08-30 00:03:02 +00:00
Sink
SLPVectorizer	SLPVectorizer: Fix assert with different sized address spaces	2018-08-31 14:34:53 +00:00
SpeculateAroundPHIs
SpeculativeExecution
SROA	[SROA] Fix alignment for uses of PHI nodes.	2018-08-30 18:59:24 +00:00
StraightLineStrengthReduce
StripDeadPrototypes
StripSymbols
StructurizeCFG	StructurizeCFG: Adjust the loop depth for a subregion to order the nodes correctly	2018-05-23 18:34:48 +00:00
SyntheticCountsPropagation
TailCallElim	[TailCallElim] Preserve DT and PDT	2018-08-04 08:13:47 +00:00
ThinLTOBitcodeWriter	[ThinLTOBitcodeWriter] Emit summaries for regular LTO modules	2018-06-01 15:20:47 +00:00
Util	[PredicateInfo] Use custom mangling to support ssa_copy with unnamed types.	2018-07-24 14:49:52 +00:00
WholeProgramDevirt