llvm-project/llvm/lib/Analysis
Nick Lewycky e0aa54bb98 This transform only handles two-operand AddRec's. Prevent it from trying to
handle anything more complex. Fixes PR10383 again!

llvm-svn: 139186
2011-09-06 21:42:18 +00:00
..
IPA Reapply r138695. Fix PassManager stack depths. 2011-08-29 17:07:00 +00:00
AliasAnalysis.cpp Misc analysis passes that need to be aware of atomic load/store. 2011-08-15 20:54:19 +00:00
AliasAnalysisCounter.cpp Teach AliasAnalysisCounter about PartialAlias. 2010-12-10 19:53:05 +00:00
AliasAnalysisEvaluator.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
AliasDebugger.cpp Extend the AliasAnalysis::pointsToConstantMemory interface to allow it 2010-11-08 16:45:26 +00:00
AliasSetTracker.cpp Atomic load/store support in LICM. 2011-08-15 20:52:09 +00:00
Analysis.cpp C API functions must be able to see their extern "C" definitions, or it will be impossible to call them from C. 2011-08-19 01:36:54 +00:00
BasicAliasAnalysis.cpp Explicitly cast narrowing conversions inside {}s that will become errors in 2011-07-27 06:22:51 +00:00
BlockFrequencyInfo.cpp Add more constantness in BlockFrequencyInfo. 2011-08-03 21:30:57 +00:00
BranchProbabilityInfo.cpp Use canonical forms for the branch probability zero heutistic. 2011-09-04 23:53:04 +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 Rewrite the CMake build to use explicit dependencies between libraries, 2011-07-29 00:14:25 +00:00
CaptureTracking.cpp Don't include Operator.h from InstrTypes.h. 2011-04-11 09:35:34 +00:00
ConstantFolding.cpp Fixes following the CR by Chris and Duncan: 2011-08-29 19:58:36 +00:00
DIBuilder.cpp Whitespace and 80-col. 2011-08-26 21:02:40 +00:00
DbgInfoPrinter.cpp Move DbgInfoPrinter specific utlities inside DbgInfoPrinter.cpp 2011-02-15 17:36:11 +00:00
DebugInfo.cpp Now, named mdnode llvm.dbg.cu keeps track of all compile units in a module. Update DebugInfoFinder to collect compile units from llvm.dbg.cu. 2011-09-06 17:40:08 +00:00
DomPrinter.cpp split dom frontier handling stuff out to its own DominanceFrontier header, 2011-01-02 22:09:33 +00:00
DominanceFrontier.cpp Move DominanceFrontier from VMCore to Analysis. 2011-01-18 06:06:27 +00:00
IVUsers.cpp Teach IVUsers to stop at non-affine expressions unless they are both 2011-07-01 22:05:19 +00:00
InlineCost.cpp Change condition for determining whether a function is small for inlining metrics so that very long functions 2011-05-24 20:22:24 +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 InstSimplify: Don't try to replace an extractvalue/insertvalue pair with the original value if types don't match. 2011-09-05 18:16:19 +00:00
Interval.cpp
IntervalPartition.cpp Now with fewer extraneous semicolons! 2010-10-07 22:25:06 +00:00
LazyValueInfo.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
LibCallAliasAnalysis.cpp Now with fewer extraneous semicolons! 2010-10-07 22:25:06 +00:00
LibCallSemantics.cpp Thread const correctness through a bunch of AliasAnalysis interfaces and 2010-08-03 21:48:53 +00:00
Lint.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
Loads.cpp Add some comments here because the lack of a check for volatile/atomic here is a bit unusual. 2011-08-15 21:56:39 +00:00
LoopDependenceAnalysis.cpp Misc analysis passes that need to be aware of atomic load/store. 2011-08-15 20:54:19 +00:00
LoopInfo.cpp LoopInfo::updateUnloop fix, and verify Block->Loop maps. 2011-08-26 03:06:34 +00:00
LoopPass.cpp Reapply r138695. Fix PassManager stack depths. 2011-08-29 17:07:00 +00:00
Makefile make -fno-rtti the default unless a directory builds with REQUIRES_RTTI. 2010-01-24 20:43:08 +00:00
MemDepPrinter.cpp Misc analysis passes that need to be aware of atomic load/store. 2011-08-15 20:54:19 +00:00
MemoryBuiltins.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
MemoryDependenceAnalysis.cpp Misc analysis passes that need to be aware of atomic load/store. 2011-08-15 20:54:19 +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 Use the new addEscapingValue callback to update GlobalsModRef when GVN adds PHIs of GEPs. For the moment, 2011-01-03 23:51:43 +00:00
PHITransAddr.cpp Shorten some expressions by using ArrayRef::slice(). 2011-07-25 15:13:01 +00:00
PathNumbering.cpp Add this back in for now. There are still a few passes which create unwind instructions at the moment. 2011-08-03 01:07:57 +00:00
PathProfileInfo.cpp Implementation of path profiling. 2011-01-29 01:09:53 +00:00
PathProfileVerifier.cpp Fix a ton of comment typos found by codespell. Patch by 2011-04-15 05:18:47 +00:00
PostDominators.cpp remove postdom frontiers, because it is dead. Forward dom frontiers are 2011-04-05 21:57:17 +00:00
ProfileEstimatorPass.cpp Fix a ton of comment typos found by codespell. Patch by 2011-04-15 05:18:47 +00:00
ProfileInfo.cpp Fix a ton of comment typos found by codespell. Patch by 2011-04-15 05:18:47 +00:00
ProfileInfoLoader.cpp Remove unused STL header includes. 2011-04-23 19:53:52 +00:00
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 When checking whether the special handling for an addrec increment which 2010-04-26 21:46:36 +00:00
RegionInfo.cpp Region: Allow user control the printing style of the print function. 2011-04-04 07:19:18 +00:00
RegionPass.cpp Reapply r138695. Fix PassManager stack depths. 2011-08-29 17:07:00 +00:00
RegionPrinter.cpp RegionPrinter: Ignore back edges when layouting the graph 2011-02-27 04:11:07 +00:00
ScalarEvolution.cpp This transform only handles two-operand AddRec's. Prevent it from trying to 2011-09-06 21:42:18 +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 Skip the landingpad instruction when determining the insertion point. 2011-08-24 21:06:46 +00:00
ScalarEvolutionNormalization.cpp Added SCEV::NoWrapFlags to manage unsigned, signed, and self wrap 2011-03-14 16:50:06 +00:00
SparsePropagation.cpp Convert debug messages to use dbgs(). Generally this means 2009-12-23 22:28:01 +00:00
Trace.cpp Convert debug messages to use dbgs(). Generally this means 2009-12-23 22:35:10 +00:00
TypeBasedAliasAnalysis.cpp Fix a ton of comment typos found by codespell. Patch by 2011-04-15 05:18:47 +00:00
ValueTracking.cpp Migrate LLVM and Clang to use the new makeArrayRef(...) functions where previously explicit non-default constructors were used. 2011-07-18 12:00:32 +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))

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