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mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-24 03:33:20 +01:00
llvm-mirror/lib/Analysis
David L Kreitzer cc655b3f3d Simplify strlen to a subtraction for certain cases.
Patch by Li Huang (li1.huang@intel.com)

Differential Revision: http://reviews.llvm.org/D18230

llvm-svn: 266200
2016-04-13 14:31:06 +00:00
..
AliasAnalysis.cpp NFC: make AtomicOrdering an enum class 2016-04-06 21:19:33 +00:00
AliasAnalysisEvaluator.cpp [PM] Make the AnalysisManager parameter to run methods a reference. 2016-03-11 11:05:24 +00:00
AliasSetTracker.cpp NFC: make AtomicOrdering an enum class 2016-04-06 21:19:33 +00:00
Analysis.cpp [ThinLTO] Move summary computation from BitcodeWriter to new pass 2016-04-11 13:58:45 +00:00
AssumptionCache.cpp [PM] Make the AnalysisManager parameter to run methods a reference. 2016-03-11 11:05:24 +00:00
BasicAliasAnalysis.cpp Don't IPO over functions that can be de-refined 2016-04-08 00:48:30 +00:00
BlockFrequencyInfo.cpp Add getBlockProfileCount method to BlockFrequencyInfo 2016-03-23 18:18:26 +00:00
BlockFrequencyInfoImpl.cpp Fix Clang-tidy readability-redundant-control-flow warnings; other minor fixes. 2016-02-02 18:20:45 +00:00
BranchProbabilityInfo.cpp Const correctness for BranchProbabilityInfo (NFC) 2016-04-07 21:59:28 +00:00
CallGraph.cpp [PM] Make the AnalysisManager parameter to run methods a reference. 2016-03-11 11:05:24 +00:00
CallGraphSCCPass.cpp Recommit r256952 "Filtering IR printing for print-after-all/print-before-all" 2016-01-06 22:55:03 +00:00
CallPrinter.cpp [CG] Rename the DOT printing pass to actually reference "DOT". 2016-03-10 11:04:40 +00:00
CaptureTracking.cpp [CaptureTracking] Support atomicrmw and cmpxchg 2016-02-18 19:23:27 +00:00
CFG.cpp Avoid overly large SmallPtrSet/SmallSet 2016-01-30 01:24:31 +00:00
CFGPrinter.cpp
CFLAliasAnalysis.cpp [CFLAA] Fix PR27213; incorrect tagging of args/globals 2016-04-05 21:40:45 +00:00
CGSCCPassManager.cpp [PM] Implement the final conclusion as to how the analysis IDs should 2016-03-11 10:22:49 +00:00
CMakeLists.txt [ThinLTO] Move summary computation from BitcodeWriter to new pass 2016-04-11 13:58:45 +00:00
CodeMetrics.cpp use range-based for loop; NFCI 2016-03-08 20:53:48 +00:00
ConstantFolding.cpp Propagate Undef in llvm.cos Intrinsic 2016-04-08 18:21:11 +00:00
CostModel.cpp Implemented cost model for masked gather and scatter operations 2015-12-28 20:10:59 +00:00
Delinearization.cpp
DemandedBits.cpp [DemandedBits] Revert r249687 due to PR26071 2016-02-03 15:05:06 +00:00
DependenceAnalysis.cpp [DependenceAnalysis] Check if result of getConstantPart is null 2016-04-04 18:13:18 +00:00
DivergenceAnalysis.cpp Introduce analysis pass to compute PostDominators in the new pass manager. NFC 2016-02-25 17:54:07 +00:00
DominanceFrontier.cpp [PM] Make the AnalysisManager parameter to run methods a reference. 2016-03-11 11:05:24 +00:00
DomPrinter.cpp Introduce analysis pass to compute PostDominators in the new pass manager. NFC 2016-02-25 17:54:07 +00:00
EHPersonalities.cpp Add Rust's personality function to the list of known personality functions 2016-03-15 20:35:45 +00:00
GlobalsModRef.cpp Don't IPO over functions that can be de-refined 2016-04-08 00:48:30 +00:00
InlineCost.cpp Refactor Threshold computation. NFC. 2016-04-08 21:28:02 +00:00
InstCount.cpp
InstructionSimplify.cpp [InstCombine] We folded an fcmp to an i1 instead of a vector of i1 2016-04-13 06:55:52 +00:00
Interval.cpp
IntervalPartition.cpp
IteratedDominanceFrontier.cpp
IVUsers.cpp Annotate dump() methods with LLVM_DUMP_METHOD, addressing Richard Smith r259192 post commit comment. 2016-01-29 20:50:44 +00:00
LazyCallGraph.cpp [PM] Make the AnalysisManager parameter to run methods a reference. 2016-03-11 11:05:24 +00:00
LazyValueInfo.cpp [LVI] Fix a bug which prevented use of !range metadata within a query 2016-03-04 22:27:39 +00:00
Lint.cpp [opaque pointer types] [NFC] FindAvailableLoadedValue: take LoadInst instead of just the pointer. 2016-01-22 01:51:51 +00:00
LLVMBuild.txt
Loads.cpp Don't IPO over functions that can be de-refined 2016-04-08 00:48:30 +00:00
LoopAccessAnalysis.cpp Re-commit [SCEV] Introduce a guarded backedge taken count and use it in LAA and LV 2016-04-08 14:29:09 +00:00
LoopInfo.cpp IR: Reserve an MDKind for !llvm.loop; NFC 2016-03-25 00:35:38 +00:00
LoopPass.cpp LoopInfo: Simplify ownership of Loop objects 2016-01-08 19:08:53 +00:00
LoopPassManager.cpp [PM] Implement the final conclusion as to how the analysis IDs should 2016-03-11 10:22:49 +00:00
LoopUnrollAnalyzer.cpp [LoopUnrollAnalyzer] Check that we're using SCEV for the same loop we're simulating. 2016-02-26 02:57:05 +00:00
MemDepPrinter.cpp [PM] Port memdep to the new pass manager. 2016-03-10 00:55:30 +00:00
MemDerefPrinter.cpp NFC. Move isDereferenceable to Loads.h/cpp 2016-02-24 12:49:04 +00:00
MemoryBuiltins.cpp Calculate __builtin_object_size when pointer depends on a condition 2016-04-13 12:25:25 +00:00
MemoryDependenceAnalysis.cpp NFC: make AtomicOrdering an enum class 2016-04-06 21:19:33 +00:00
MemoryLocation.cpp
ModuleDebugInfoPrinter.cpp
ModuleSummaryAnalysis.cpp [ThinLTO] Move summary computation from BitcodeWriter to new pass 2016-04-11 13:58:45 +00:00
ObjCARCAliasAnalysis.cpp [PM] Make the AnalysisManager parameter to run methods a reference. 2016-03-11 11:05:24 +00:00
ObjCARCAnalysisUtils.cpp
ObjCARCInstKind.cpp Add support for objc_unsafeClaimAutoreleasedReturnValue to the 2016-01-27 19:05:08 +00:00
OrderedBasicBlock.cpp
PHITransAddr.cpp Annotate dump() methods with LLVM_DUMP_METHOD, addressing Richard Smith r259192 post commit comment. 2016-01-29 20:50:44 +00:00
PostDominators.cpp [PM] Make the AnalysisManager parameter to run methods a reference. 2016-03-11 11:05:24 +00:00
PtrUseVisitor.cpp
README.txt
RegionInfo.cpp [PM] Make the AnalysisManager parameter to run methods a reference. 2016-03-11 11:05:24 +00:00
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp Add space between words in verify-scev-maps option help message 2016-04-12 23:21:46 +00:00
ScalarEvolutionAliasAnalysis.cpp [PM] Make the AnalysisManager parameter to run methods a reference. 2016-03-11 11:05:24 +00:00
ScalarEvolutionExpander.cpp Re-commit [SCEV] Introduce a guarded backedge taken count and use it in LAA and LV 2016-04-08 14:29:09 +00:00
ScalarEvolutionNormalization.cpp
ScopedNoAliasAA.cpp [PM] Make the AnalysisManager parameter to run methods a reference. 2016-03-11 11:05:24 +00:00
SparsePropagation.cpp
StratifiedSets.h
TargetLibraryInfo.cpp [NVPTX] Infer __nvvm_reflect as nounwind, readnone 2016-03-31 21:29:57 +00:00
TargetTransformInfo.cpp [LoopDataPrefetch] Add TTI to limit the number of iterations to prefetch ahead 2016-03-18 00:27:43 +00:00
Trace.cpp Annotate dump() methods with LLVM_DUMP_METHOD, addressing Richard Smith r259192 post commit comment. 2016-01-29 20:50:44 +00:00
TypeBasedAliasAnalysis.cpp [PM] Make the AnalysisManager parameter to run methods a reference. 2016-03-11 11:05:24 +00:00
ValueTracking.cpp Simplify strlen to a subtraction for certain cases. 2016-04-13 14:31:06 +00:00
VectorUtils.cpp [InstCombine] We folded an fcmp to an i1 instead of a vector of i1 2016-04-13 06:55:52 +00:00

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))

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