llvm-project/llvm/lib/Analysis
Hal Finkel 1140e1704b Revert "r251451 - [AliasSetTracker] Use mod/ref information for UnknownInstr"
It looks like this broke the stage 2 builder:
  http://lab.llvm.org:8080/green/job/clang-stage2-configure-Rlto/6989/

Original commit message:

AliasSetTracker does not need to convert the access mode to ModRefAccess if the
new visited UnknownInst has only 'REF' modrefinfo to existing pointers in the
sets.

Patch by Andrew Zhogin!

llvm-svn: 251562
2015-10-28 22:13:41 +00:00
..
AliasAnalysis.cpp [AA] Enhance the new AliasAnalysis infrastructure with an optional 2015-10-21 12:15:19 +00:00
AliasAnalysisEvaluator.cpp Analysis: Remove implicit ilist iterator conversions 2015-10-10 00:53:03 +00:00
AliasSetTracker.cpp Revert "r251451 - [AliasSetTracker] Use mod/ref information for UnknownInstr" 2015-10-28 22:13:41 +00:00
Analysis.cpp [PM/AA] Rebuild LLVM's alias analysis infrastructure in a way compatible 2015-09-09 17:55:00 +00:00
AssumptionCache.cpp [PM] Actually add the new pass manager support for the assumption cache. 2015-01-22 21:53:09 +00:00
BasicAliasAnalysis.cpp [AliasAnalysis] Take into account readnone attribute for the function arguments 2015-10-28 17:54:48 +00:00
BlockFrequencyInfo.cpp Recommit r250345, it was reverted in r250366 to investigate a bot failure. 2015-10-15 14:59:40 +00:00
BlockFrequencyInfoImpl.cpp Recommit r250345, it was reverted in r250366 to investigate a bot failure. 2015-10-15 14:59:40 +00:00
BranchProbabilityInfo.cpp Check the case that the numerator and denominator are both zeros when getting edge probabilities in BPI and return 100% in this case. 2015-10-26 18:00:17 +00:00
CFG.cpp Analysis: Remove implicit ilist iterator conversions 2015-10-10 00:53:03 +00:00
CFGPrinter.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
CFLAliasAnalysis.cpp [PM/AA] Rebuild LLVM's alias analysis infrastructure in a way compatible 2015-09-09 17:55:00 +00:00
CGSCCPassManager.cpp [PM] Remove the defunt CGSCC-specific debug flag. 2015-01-13 22:45:13 +00:00
CMakeLists.txt [PM/AA] Rebuild LLVM's alias analysis infrastructure in a way compatible 2015-09-09 17:55:00 +00:00
CallGraph.cpp [PM/AA] Remove the last relics of the separate IPA library from LLVM, 2015-08-18 17:51:53 +00:00
CallGraphSCCPass.cpp [PM/AA] Remove the last relics of the separate IPA library from LLVM, 2015-08-18 17:51:53 +00:00
CallPrinter.cpp [PM/AA] Remove the last relics of the separate IPA library from LLVM, 2015-08-18 17:51:53 +00:00
CaptureTracking.cpp [IR] Give catchret an optional 'return value' operand 2015-08-15 02:46:08 +00:00
CodeMetrics.cpp Use all_of to simplify control flow. NFC. 2015-10-24 19:30:37 +00:00
ConstantFolding.cpp Enable constant propagation for more math functions 2015-08-27 19:56:57 +00:00
CostModel.cpp Analysis: Remove implicit ilist iterator conversions 2015-10-10 00:53:03 +00:00
Delinearization.cpp SCEV: Allow simple AddRec * Parameter products in delinearization 2015-10-12 08:02:00 +00:00
DemandedBits.cpp Compute demanded bits for icmp instructions 2015-10-08 12:40:06 +00:00
DependenceAnalysis.cpp [SCEV] Introduce ScalarEvolution::getOne and getZero. 2015-09-23 01:59:04 +00:00
DivergenceAnalysis.cpp Analysis: Remove implicit ilist iterator conversions 2015-10-10 00:53:03 +00:00
DomPrinter.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
DominanceFrontier.cpp Templatify DominanceFrontier. 2014-07-12 21:59:52 +00:00
GlobalsModRef.cpp [GlobalsAA] An indirect global that is initialized is not fair game 2015-10-28 10:41:29 +00:00
IVUsers.cpp Analysis: Remove implicit ilist iterator conversions 2015-10-10 00:53:03 +00:00
InlineCost.cpp Analysis: Remove implicit ilist iterator conversions 2015-10-10 00:53:03 +00:00
InstCount.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
InstructionSimplify.cpp [ValueTracking] Expose `implies` via ValueTracking, NFC 2015-10-28 03:20:19 +00:00
Interval.cpp Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges." 2014-07-21 17:06:51 +00:00
IntervalPartition.cpp [C++11] More 'nullptr' conversion. In some cases just using a boolean check instead of comparing to nullptr. 2014-04-15 04:59:12 +00:00
IteratedDominanceFrontier.cpp Move IDF Calculation to a separate file, expose an interface to it. 2015-04-21 19:13:02 +00:00
LLVMBuild.txt [PM/AA] Remove the last relics of the separate IPA library from LLVM, 2015-08-18 17:51:53 +00:00
LazyCallGraph.cpp Revert r225854: [PM] Move the LazyCallGraph printing functionality to 2015-01-14 00:27:45 +00:00
LazyValueInfo.cpp [LazyValueInfo] Report nonnull range for nonnull pointers 2015-09-18 13:01:48 +00:00
LibCallSemantics.cpp [WinEH] Recognize CoreCLR personality function 2015-10-06 20:28:16 +00:00
Lint.cpp Analysis: Remove implicit ilist iterator conversions 2015-10-10 00:53:03 +00:00
Loads.cpp Analysis: Remove implicit ilist iterator conversions 2015-10-10 00:53:03 +00:00
LoopAccessAnalysis.cpp Put global classes into the appropriate namespace. 2015-10-28 13:54:36 +00:00
LoopInfo.cpp [IR] Add token types 2015-08-14 05:09:07 +00:00
LoopPass.cpp LoopPass: Remove redoLoop, it isn't used. NFC 2015-10-22 21:31:34 +00:00
Makefile [PM/AA] Remove the last relics of the separate IPA library from LLVM, 2015-08-18 17:51:53 +00:00
MemDepPrinter.cpp [PM/AA] Rebuild LLVM's alias analysis infrastructure in a way compatible 2015-09-09 17:55:00 +00:00
MemDerefPrinter.cpp Take alignment into account in isSafeToSpeculativelyExecute and isSafeToLoadUnconditionally. 2015-08-17 15:54:26 +00:00
MemoryBuiltins.cpp Use find_if to simplify control flow. NFC. 2015-10-24 19:03:15 +00:00
MemoryDependenceAnalysis.cpp Analysis: Remove implicit ilist iterator conversions 2015-10-10 00:53:03 +00:00
MemoryLocation.cpp [PM/AA] Split the location computation out of getArgLocation so the 2015-06-17 07:12:40 +00:00
ModuleDebugInfoPrinter.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
ObjCARCAliasAnalysis.cpp [PM/AA] Rebuild LLVM's alias analysis infrastructure in a way compatible 2015-09-09 17:55:00 +00:00
ObjCARCAnalysisUtils.cpp [ARC] Pull the ObjC ARC components that really serve the role of 2015-08-20 08:06:03 +00:00
ObjCARCInstKind.cpp Analysis: Remove implicit ilist iterator conversions 2015-10-10 00:53:03 +00:00
OrderedBasicBlock.cpp [CaptureTracker] Provide an ordered basic block to PointerMayBeCapturedBefore 2015-07-31 14:31:35 +00:00
PHITransAddr.cpp [PHITransAddr] Don't assume that instruction operands are translatable 2015-08-09 15:43:02 +00:00
PostDominators.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
PtrUseVisitor.cpp Update SetVector to rely on the underlying set's insert to return a pair<iterator, bool> 2014-11-19 07:49:26 +00:00
README.txt
RegionInfo.cpp [RegionInfo] Add debug-time region viewer functions 2015-08-10 13:21:59 +00:00
RegionPass.cpp Change range-based for-loops to be -Wrange-loop-analysis clean. 2015-04-15 01:21:15 +00:00
RegionPrinter.cpp [RegionInfo] Add debug-time region viewer functions 2015-08-10 13:21:59 +00:00
ScalarEvolution.cpp [SCEV] Compute max backedge count for loops with "shift ivs" 2015-10-28 21:27:14 +00:00
ScalarEvolutionAliasAnalysis.cpp [PM/AA] Rebuild LLVM's alias analysis infrastructure in a way compatible 2015-09-09 17:55:00 +00:00
ScalarEvolutionExpander.cpp [ScalarEvolutionExpander] PHI on a catchpad can be used on both edges 2015-10-27 19:48:28 +00:00
ScalarEvolutionNormalization.cpp Analysis: Remove implicit ilist iterator conversions 2015-10-10 00:53:03 +00:00
ScopedNoAliasAA.cpp Fix Clang-tidy modernize-use-nullptr warnings in source directories and generated files; other minor cleanups. 2015-10-06 23:24:35 +00:00
SparsePropagation.cpp Analysis: Remove implicit ilist iterator conversions 2015-10-10 00:53:03 +00:00
StratifiedSets.h Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
TargetLibraryInfo.cpp WebAssembly: disable some loop-idiom recognition 2015-10-28 17:50:23 +00:00
TargetTransformInfo.cpp Scalarizer for masked.gather and masked.scatter intrinsics. 2015-10-25 15:37:55 +00:00
Trace.cpp
TypeBasedAliasAnalysis.cpp [PM/AA] Rebuild LLVM's alias analysis infrastructure in a way compatible 2015-09-09 17:55:00 +00:00
ValueTracking.cpp [ValueTracking] Expose `implies` via ValueTracking, NFC 2015-10-28 03:20:19 +00:00
VectorUtils.cpp [LoopVectorize] Shrink integer operations into the smallest type possible 2015-10-12 12:34:45 +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))

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