llvm-6502/lib/Analysis
Dan Gohman e059ee832c Don't back past debug info intrinsics; SCEVExpander's strategy
for ignoring debug info intrinsics everywhere else is to advance
past them, and it needs to be consistent.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99332 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-23 21:53:22 +00:00
..
IPA backing out r99170 because it still fails on clang-x86_64-darwin10-fnt 2010-03-22 09:11:00 +00:00
AliasAnalysis.cpp
AliasAnalysisCounter.cpp Fix a missing newline in debug output. 2010-03-01 17:42:55 +00:00
AliasAnalysisEvaluator.cpp There are two ways of checking for a given type, for example isa<PointerType>(T) 2010-02-16 11:11:14 +00:00
AliasDebugger.cpp adopt getAdjustedAnalysisPointer in a few more passes. 2010-01-20 20:09:02 +00:00
AliasSetTracker.cpp
Analysis.cpp
BasicAliasAnalysis.cpp There are two ways of checking for a given type, for example isa<PointerType>(T) 2010-02-16 11:11:14 +00:00
CaptureTracking.cpp There are two ways of checking for a given type, for example isa<PointerType>(T) 2010-02-16 11:11:14 +00:00
CFGPrinter.cpp
CMakeLists.txt
ConstantFolding.cpp FP16 constfolding 2010-03-19 00:36:35 +00:00
DbgInfoPrinter.cpp
DebugInfo.cpp Start using DIFile. See updated SourceLevelDebugging.html for more information. 2010-03-09 00:44:10 +00:00
DomPrinter.cpp Create Generic DOTGraphTraits Printer/Viewer 2010-01-16 10:56:41 +00:00
InlineCost.cpp Treat copysignl like the other copysign functions. 2010-03-15 14:01:44 +00:00
InstCount.cpp
InstructionSimplify.cpp fix incorrect folding of icmp with undef, PR6481. 2010-03-03 19:46:03 +00:00
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp Spelling fixes. 2010-03-01 17:49:51 +00:00
LazyValueInfo.cpp
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
LiveValues.cpp Fix "the the" and similar typos. 2010-02-10 16:03:48 +00:00
LoopDependenceAnalysis.cpp Define placement new wrappers for BumpPtrAllocator and 2010-03-18 18:49:47 +00:00
LoopInfo.cpp Add a DominatorTree argument to isLCSSA so that it doesn't have to 2010-03-10 19:38:49 +00:00
LoopPass.cpp eliminate a bunch more unneeded dynamic_cast's. 2010-01-22 05:37:10 +00:00
Makefile make -fno-rtti the default unless a directory builds with REQUIRES_RTTI. 2010-01-24 20:43:08 +00:00
MemoryBuiltins.cpp Fix "the the" and similar typos. 2010-02-10 16:03:48 +00:00
MemoryDependenceAnalysis.cpp Reapply r97010, the speculative revert failed. 2010-02-24 08:48:04 +00:00
PHITransAddr.cpp Reapply r97010, the speculative revert failed. 2010-02-24 08:48:04 +00:00
PointerTracking.cpp There are two ways of checking for a given type, for example isa<PointerType>(T) 2010-02-16 11:11:14 +00:00
PostDominators.cpp
ProfileEstimatorPass.cpp adopt getAdjustedAnalysisPointer in a few more passes. 2010-01-20 20:09:02 +00:00
ProfileInfo.cpp adopt getAdjustedAnalysisPointer in a few more passes. 2010-01-20 20:09:02 +00:00
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp adopt getAdjustedAnalysisPointer in a few more passes. 2010-01-20 20:09:02 +00:00
ProfileVerifierPass.cpp
README.txt
ScalarEvolution.cpp Define placement new wrappers for BumpPtrAllocator and 2010-03-18 18:49:47 +00:00
ScalarEvolutionAliasAnalysis.cpp Add a comment. 2010-03-01 17:56:04 +00:00
ScalarEvolutionExpander.cpp Don't back past debug info intrinsics; SCEVExpander's strategy 2010-03-23 21:53:22 +00:00
SparsePropagation.cpp
Trace.cpp
ValueTracking.cpp Fix a typo in ValueTracking that's causing instcombine to delete needed shift instructions. 2010-03-13 02:20:29 +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.

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