llvm-6502/lib/Analysis
Eric Christopher 1cf9e7ff96 Fix typo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@196434 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-04 23:55:09 +00:00
..
IPA [PM] Split the CallGraph out from the ModulePass which creates the 2013-11-26 04:19:30 +00:00
AliasAnalysis.cpp
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp
AliasSetTracker.cpp In AliasSetTracker, do not change the alias set to "mod/ref" when adding 2013-09-12 20:15:50 +00:00
Analysis.cpp delinearization of arrays 2013-11-12 22:47:20 +00:00
BasicAliasAnalysis.cpp Use correct size for address space in BasicAA. 2013-11-16 00:36:43 +00:00
BlockFrequencyInfo.cpp Added BlockFrequencyInfo::view for displaying the block frequency propagation graph via graphviz. 2013-11-14 02:27:46 +00:00
BranchProbabilityInfo.cpp Consider (x == -1) unlikely in BranchProbabilityInfo 2013-11-01 10:58:22 +00:00
CaptureTracking.cpp CaptureTracking: Plug a loophole in the "too many uses" heuristic. 2013-10-03 13:24:02 +00:00
CFG.cpp
CFGPrinter.cpp
CMakeLists.txt delinearization of arrays 2013-11-12 22:47:20 +00:00
CodeMetrics.cpp
ConstantFolding.cpp Add addrspacecast instruction. 2013-11-15 01:34:59 +00:00
CostModel.cpp Move variable into assert to avoid unused variable warning. 2013-09-17 21:13:57 +00:00
Delinearization.cpp add more comments around the delinearization of arrays 2013-11-13 22:37:58 +00:00
DependenceAnalysis.cpp add more comments around the delinearization of arrays 2013-11-13 22:37:58 +00:00
DominanceFrontier.cpp
DomPrinter.cpp
InstCount.cpp
InstructionSimplify.cpp Teach MemoryBuiltins and InstructionSimplify that operator new never returns NULL. 2013-09-24 16:37:51 +00:00
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp
LazyValueInfo.cpp
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp Use size function instead of manually calculating it. 2013-11-10 03:18:50 +00:00
LLVMBuild.txt
Loads.cpp
LoopInfo.cpp Simplify code. No functionality change. 2013-11-13 20:18:38 +00:00
LoopPass.cpp
Makefile
MemDepPrinter.cpp Fix typo. 2013-12-04 23:55:09 +00:00
MemoryBuiltins.cpp fix PR17635: false positive with packed structures 2013-10-24 09:17:24 +00:00
MemoryDependenceAnalysis.cpp Fixing a heisenbug where the memory dependence analysis behaves differently 2013-11-14 01:10:52 +00:00
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp
PHITransAddr.cpp
PostDominators.cpp
PtrUseVisitor.cpp
README.txt
RegionInfo.cpp
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp Annotate APInt methods where it's not clear whether they are in place with warn_unused_result. 2013-11-16 16:25:41 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp Fix SCEVExpander: don't try to expand quadratic recurrences outside a loop. 2013-10-25 21:35:56 +00:00
ScalarEvolutionNormalization.cpp Fix LSR: don't normalize quadratic recurrences. 2013-10-25 21:35:52 +00:00
SparsePropagation.cpp
TargetTransformInfo.cpp Costmodel: Add support for horizontal vector reductions 2013-09-17 18:06:50 +00:00
Trace.cpp
TypeBasedAliasAnalysis.cpp TBAA: fix PR17620. 2013-10-22 01:40:25 +00:00
ValueTracking.cpp Don't speculate loads under ThreadSanitizer 2013-11-21 07:29:28 +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))

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