llvm-6502/lib/Analysis
Bruno Cardoso Lopes 8fea35acad [CaptureTracker] Provide an ordered basic block to PointerMayBeCapturedBefore
This patch is a follow up from r240560 and is a step further into
mitigating the compile time performance issues in CaptureTracker.

By providing the CaptureTracker with a "cached ordered basic block"
instead of computing it every time, MemDepAnalysis can use this cache
throughout its calls to AA->callCapturesBefore, avoiding to recompute it
for every scanned instruction. In the same testcase used in r240560,
compile time is reduced from 2min to 30s.

This also fixes PR22348.

rdar://problem/19230319
Differential Revision: http://reviews.llvm.org/D11364

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243750 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-31 14:31:35 +00:00
..
IPA Rename hasCompatibleFunctionAttributes->areInlineCompatible based 2015-07-29 22:09:48 +00:00
AliasAnalysis.cpp [CaptureTracker] Provide an ordered basic block to PointerMayBeCapturedBefore 2015-07-31 14:31:35 +00:00
AliasAnalysisCounter.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
AliasAnalysisEvaluator.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
AliasDebugger.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
AliasSetTracker.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
Analysis.cpp Create a wrapper pass for BranchProbabilityInfo. 2015-07-15 22:48:29 +00:00
AssumptionCache.cpp
BasicAliasAnalysis.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
BlockFrequencyInfo.cpp Add new constructors for LoopInfo/DominatorTree/BFI/BPI 2015-07-16 23:23:35 +00:00
BlockFrequencyInfoImpl.cpp
BranchProbabilityInfo.cpp Create a wrapper pass for BranchProbabilityInfo. 2015-07-15 22:48:29 +00:00
CaptureTracking.cpp [CaptureTracker] Provide an ordered basic block to PointerMayBeCapturedBefore 2015-07-31 14:31:35 +00:00
CFG.cpp
CFGPrinter.cpp
CFLAliasAnalysis.cpp
CGSCCPassManager.cpp
CMakeLists.txt [CaptureTracker] Provide an ordered basic block to PointerMayBeCapturedBefore 2015-07-31 14:31:35 +00:00
CodeMetrics.cpp
ConstantFolding.cpp Fix assert when inlining a constantexpr addrspacecast 2015-07-27 18:31:03 +00:00
CostModel.cpp Roll forward r243250 2015-07-26 19:10:03 +00:00
Delinearization.cpp Move delinearization from SCEVAddRecExpr to ScalarEvolution 2015-06-29 14:42:48 +00:00
DependenceAnalysis.cpp Move delinearization from SCEVAddRecExpr to ScalarEvolution 2015-06-29 14:42:48 +00:00
DivergenceAnalysis.cpp
DominanceFrontier.cpp
DomPrinter.cpp
InstCount.cpp
InstructionSimplify.cpp [InstSimplify] Teach InstSimplify how to simplify extractelement 2015-07-13 01:15:53 +00:00
Interval.cpp
IntervalPartition.cpp
IteratedDominanceFrontier.cpp
IVUsers.cpp [LSR] don't attempt to promote ephemeral values to indvars 2015-07-13 03:28:53 +00:00
LazyCallGraph.cpp
LazyValueInfo.cpp [LVI] Cleanup whitespaces. NFC 2015-07-28 15:53:21 +00:00
LibCallAliasAnalysis.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
LibCallSemantics.cpp
Lint.cpp
LLVMBuild.txt
Loads.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
LoopAccessAnalysis.cpp [LAA] Add clarifying comments for the checking pointer grouping algorithm. NFC 2015-07-28 13:44:08 +00:00
LoopInfo.cpp Add new constructors for LoopInfo/DominatorTree/BFI/BPI 2015-07-16 23:23:35 +00:00
LoopPass.cpp
Makefile
MemDepPrinter.cpp
MemDerefPrinter.cpp
MemoryBuiltins.cpp
MemoryDependenceAnalysis.cpp [CaptureTracker] Provide an ordered basic block to PointerMayBeCapturedBefore 2015-07-31 14:31:35 +00:00
MemoryLocation.cpp
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
OrderedBasicBlock.cpp [CaptureTracker] Provide an ordered basic block to PointerMayBeCapturedBefore 2015-07-31 14:31:35 +00:00
PHITransAddr.cpp
PostDominators.cpp
PtrUseVisitor.cpp
README.txt
RegionInfo.cpp
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp [SCEV] Apply NSW and NUW flags via poison value analysis 2015-07-28 18:22:40 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp
ScalarEvolutionNormalization.cpp
ScopedNoAliasAA.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
SparsePropagation.cpp
StratifiedSets.h
TargetLibraryInfo.cpp
TargetTransformInfo.cpp Rename hasCompatibleFunctionAttributes->areInlineCompatible based 2015-07-29 22:09:48 +00:00
Trace.cpp
TypeBasedAliasAnalysis.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
ValueTracking.cpp [SCEV] Apply NSW and NUW flags via poison value analysis 2015-07-28 18:22:40 +00:00
VectorUtils.cpp [InstSimplify] Teach InstSimplify how to simplify extractelement 2015-07-13 01:15:53 +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))

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