llvm-6502

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IPA
AliasAnalysis.cpp
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp
AliasSetTracker.cpp
Analysis.cpp
BasicAliasAnalysis.cpp
BlockFrequencyInfo.cpp
BlockFrequencyInfoImpl.cpp
BranchProbabilityInfo.cpp	[Modules] Fix potential ODR violations by sinking the DEBUG_TYPE	2014-04-22 02:48:03 +00:00
CaptureTracking.cpp
CFG.cpp
CFGPrinter.cpp
CGSCCPassManager.cpp
CMakeLists.txt
CodeMetrics.cpp
ConstantFolding.cpp
CostModel.cpp
Delinearization.cpp
DependenceAnalysis.cpp
DominanceFrontier.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
DomPrinter.cpp	[PM] Split DominatorTree into a concrete analysis result object which	2014-01-13 13:07:17 +00:00
InstCount.cpp
InstructionSimplify.cpp
Interval.cpp	[Modules] Move CFG.h to the IR library as it defines graph traits over	2014-03-04 11:45:46 +00:00
IntervalPartition.cpp
IVUsers.cpp
LazyCallGraph.cpp	[LCG] Switch a weird do/while loop that actually couldn't fail its	2014-04-24 21:19:30 +00:00
LazyValueInfo.cpp
LibCallAliasAnalysis.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
LibCallSemantics.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
Lint.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
LLVMBuild.txt
Loads.cpp
LoopInfo.cpp
LoopPass.cpp
Makefile	make -fno-rtti the default unless a directory builds with REQUIRES_RTTI.	2010-01-24 20:43:08 +00:00
MemDepPrinter.cpp
MemoryBuiltins.cpp	[Modules] Fix potential ODR violations by sinking the DEBUG_TYPE	2014-04-22 02:48:03 +00:00
MemoryDependenceAnalysis.cpp
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp
PHITransAddr.cpp
PostDominators.cpp
PtrUseVisitor.cpp
README.txt
RegionInfo.cpp
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp
ScalarEvolutionAliasAnalysis.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
ScalarEvolutionExpander.cpp
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp
TargetTransformInfo.cpp	[Modules] Fix potential ODR violations by sinking the DEBUG_TYPE	2014-04-22 02:48:03 +00:00
Trace.cpp
TypeBasedAliasAnalysis.cpp
ValueTracking.cpp

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))

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