llvm-6502/lib/Analysis
Duncan Sands 124708d9b4 Revert commit 122654 at the request of Chris, who reckons that instsimplify
is the wrong hammer for this nail, and is probably right.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122661 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-01 20:08:02 +00:00
..
IPA Move Value::getUnderlyingObject to be a standalone 2010-12-15 20:02:24 +00:00
AliasAnalysis.cpp Make memcpyopt TBAA-aware. 2010-12-16 02:51:19 +00:00
AliasAnalysisCounter.cpp Teach AliasAnalysisCounter about PartialAlias. 2010-12-10 19:53:05 +00:00
AliasAnalysisEvaluator.cpp Teach AliasAnalysisEvaluator about PartialAlias. 2010-12-10 19:52:40 +00:00
AliasDebugger.cpp Extend the AliasAnalysis::pointsToConstantMemory interface to allow it 2010-11-08 16:45:26 +00:00
AliasSetTracker.cpp Update this code to handle PartialAlias as MayAlias. 2010-12-10 19:40:47 +00:00
Analysis.cpp Add initialization routines for Analysis and IPA. 2010-10-07 18:31:00 +00:00
BasicAliasAnalysis.cpp Reapply r121886, and also update DecomposeGEPExpression to keep 2010-12-15 20:49:55 +00:00
CaptureTracking.cpp VAArg doesn't capture its operand. 2010-11-09 20:09:35 +00:00
CFGPrinter.cpp Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
CMakeLists.txt Introduce DIBuilder. It is intended to be a front-end friendly interface to emit debuggging information entries in LLVM IR. 2010-11-04 15:01:38 +00:00
ConstantFolding.cpp Change all self assignments X=X to (void)X, so that we can turn on a 2010-12-23 00:58:24 +00:00
DbgInfoPrinter.cpp Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
DebugInfo.cpp Add support to create class type. 2010-12-08 20:18:20 +00:00
DIBuilder.cpp Use type's file info while describing inheritance relationship. 2010-12-08 21:46:37 +00:00
DomPrinter.cpp Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
InlineCost.cpp Now using a variant of the existing inlining heuristics to decide whether to create a given specialization of a function in PartialSpecialization. If the total performance bonus across all callsites passing the same constant exceeds the specialization cost, we create the specialization. 2010-10-09 22:06:36 +00:00
InstCount.cpp Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
InstructionSimplify.cpp Revert commit 122654 at the request of Chris, who reckons that instsimplify 2011-01-01 20:08:02 +00:00
Interval.cpp
IntervalPartition.cpp Now with fewer extraneous semicolons! 2010-10-07 22:25:06 +00:00
IVUsers.cpp Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
LazyValueInfo.cpp Speculatively revert the use of DenseMap in LazyValueInfo, which may be causing Linux self-host failures. 2010-12-20 23:53:19 +00:00
LibCallAliasAnalysis.cpp Now with fewer extraneous semicolons! 2010-10-07 22:25:06 +00:00
LibCallSemantics.cpp
Lint.cpp Move Value::getUnderlyingObject to be a standalone 2010-12-15 20:02:24 +00:00
LiveValues.cpp Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
Loads.cpp Move Value::getUnderlyingObject to be a standalone 2010-12-15 20:02:24 +00:00
LoopDependenceAnalysis.cpp Move Value::getUnderlyingObject to be a standalone 2010-12-15 20:02:24 +00:00
LoopInfo.cpp Fix typo pointed out by Trevor Harmon. 2010-11-13 12:16:27 +00:00
LoopPass.cpp zap dead code. 2010-09-04 18:12:00 +00:00
Makefile
MemDepPrinter.cpp Add helper functions for computing the Location of load, store, 2010-11-11 21:50:19 +00:00
MemoryBuiltins.cpp
MemoryDependenceAnalysis.cpp Change all self assignments X=X to (void)X, so that we can turn on a 2010-12-23 00:58:24 +00:00
ModuleDebugInfoPrinter.cpp Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
NoAliasAnalysis.cpp Extend the AliasAnalysis::pointsToConstantMemory interface to allow it 2010-11-08 16:45:26 +00:00
PHITransAddr.cpp Strip trailing whitespace. 2010-11-18 17:06:31 +00:00
PostDominators.cpp Begin adding static dependence information to passes, which will allow us to 2010-10-12 19:48:12 +00:00
ProfileEstimatorPass.cpp Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
ProfileInfo.cpp Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
ProfileVerifierPass.cpp Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
README.txt
RegionInfo.cpp Make some symbols static, move classes into anonymous namespaces. 2010-10-22 17:35:07 +00:00
RegionPass.cpp Remove useless dynamic_cast<>(). 2010-12-12 21:58:28 +00:00
RegionPrinter.cpp Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
ScalarEvolution.cpp PR5207: Change APInt methods trunc(), sext(), zext(), sextOrTrunc() and 2010-12-07 08:25:19 +00:00
ScalarEvolutionAliasAnalysis.cpp Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which 2010-10-19 17:21:58 +00:00
ScalarEvolutionExpander.cpp Introduce memoization for ScalarEvolution dominates and properlyDominates 2010-11-18 00:34:22 +00:00
ScalarEvolutionNormalization.cpp Disable the asserts that check that normalization is perfectly 2010-09-03 22:12:56 +00:00
SparsePropagation.cpp
Trace.cpp
TypeBasedAliasAnalysis.cpp Update a comment. 2010-12-16 02:55:10 +00:00
ValueTracking.cpp move isBytewiseValue out to ValueTracking.h/cpp 2010-12-26 20:15:01 +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))

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