llvm/Analysis at d7628daffa022c931ceb45de640d3ff8522d9912 - llvm

RPCSX/llvm

mirror of https://github.com/RPCSX/llvm.git synced 2024-12-13 14:46:53 +00:00

History

Easwaran Raman a4f47922ff Add ProfileData to required_libraries This should fix ppc64be build breakage due to r266477 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266488 91177308-0d34-0410-b5e6-96231b3b80d8		2016-04-15 23:08:52 +00:00
..
AliasAnalysis.cpp
AliasAnalysisEvaluator.cpp
AliasSetTracker.cpp	[AliasSetTracker] Correctly handle changing the size of an entry	2016-04-14 22:00:11 +00:00
Analysis.cpp	[ThinLTO] Move summary computation from BitcodeWriter to new pass	2016-04-11 13:58:45 +00:00
AssumptionCache.cpp
BasicAliasAnalysis.cpp
BlockFrequencyInfo.cpp
BlockFrequencyInfoImpl.cpp
BranchProbabilityInfo.cpp
CallGraph.cpp
CallGraphSCCPass.cpp
CallPrinter.cpp
CaptureTracking.cpp
CFG.cpp
CFGPrinter.cpp
CFLAliasAnalysis.cpp	[CFLAA] Fix up code style a bit. NFC.	2016-04-13 23:27:37 +00:00
CGSCCPassManager.cpp
CMakeLists.txt	[ThinLTO] Move summary computation from BitcodeWriter to new pass	2016-04-11 13:58:45 +00:00
CodeMetrics.cpp
ConstantFolding.cpp	Propagate Undef in llvm.cos Intrinsic	2016-04-08 18:21:11 +00:00
CostModel.cpp	[CodeGen] Teach LLVM how to lower @llvm.{min,max}num to {MIN,MAX}NAN	2016-04-14 07:13:24 +00:00
Delinearization.cpp
DemandedBits.cpp
DependenceAnalysis.cpp
DivergenceAnalysis.cpp	[DivergenceAnalysis] Treat PHI with incoming undef as constant	2016-04-14 17:42:47 +00:00
DominanceFrontier.cpp
DomPrinter.cpp
EHPersonalities.cpp
GlobalsModRef.cpp
InlineCost.cpp	Replace the use of MaxFunctionCount module flag	2016-04-15 21:39:58 +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
LazyCallGraph.cpp
LazyValueInfo.cpp
Lint.cpp
LLVMBuild.txt	Add ProfileData to required_libraries	2016-04-15 23:08:52 +00:00
Loads.cpp
LoopAccessAnalysis.cpp	[SCEV][LAA] Add tests for SCEV expression transformations performed during LAA	2016-04-14 16:08:45 +00:00
LoopInfo.cpp
LoopPass.cpp
LoopPassManager.cpp
LoopUnrollAnalyzer.cpp
MemDepPrinter.cpp
MemDerefPrinter.cpp
MemoryBuiltins.cpp	Calculate __builtin_object_size when pointer depends on a condition	2016-04-13 12:25:25 +00:00
MemoryDependenceAnalysis.cpp
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
ObjCARCAnalysisUtils.cpp
ObjCARCInstKind.cpp
OrderedBasicBlock.cpp
PHITransAddr.cpp
PostDominators.cpp
PtrUseVisitor.cpp
README.txt
RegionInfo.cpp
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp	[SCEV][LAA] Add tests for SCEV expression transformations performed during LAA	2016-04-14 16:08:45 +00:00
ScalarEvolutionAliasAnalysis.cpp
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
SparsePropagation.cpp
StratifiedSets.h	[CFLAA] Fix up code style a bit. NFC.	2016-04-13 23:27:37 +00:00
TargetLibraryInfo.cpp
TargetTransformInfo.cpp	[TTI] Add getInliningThresholdMultiplier.	2016-04-15 01:38:48 +00:00
Trace.cpp
TypeBasedAliasAnalysis.cpp
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

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))

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