llvm-project

History

Dan Gohman c70e994364 Fix SCEVExpander's existing PHI reuse checking to recognize the case where there are loop-invariant instructions somehow left inside the loop, and in a position where they won't dominate the IV increment position. llvm-svn: 96448		2010-02-17 02:39:31 +00:00
..
IPA	There are two ways of checking for a given type, for example isa<PointerType>(T)	2010-02-16 11:11:14 +00:00
AliasAnalysis.cpp	Partially address a README by having functionattrs consider calls to	2010-01-06 08:45:52 +00:00
AliasAnalysisCounter.cpp	drop the pass name from the output.	2010-01-22 05:52:51 +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	Change dbgs() back to errs() as Chris requested.	2009-12-23 22:49:57 +00:00
Analysis.cpp	"In order to ease automatic bindings generation, it would be helpful if boolean values were distinguishable from integers. The attached patch introduces "typedef int LLVMBool;", and uses LLVMBool instead of int throughout the C API, wherever a boolean value is called for."	2010-01-09 22:27:07 +00:00
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
CFGPrinter.cpp	Remove includes of Support/Compiler.h that are no longer needed after the	2009-10-25 06:57:41 +00:00
CMakeLists.txt	add to cmake	2009-12-04 04:15:36 +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
ConstantFolding.cpp	Fold bswap(undef) to undef.	2010-02-17 00:54:58 +00:00
DbgInfoPrinter.cpp	Remove dead debug info intrinsics.	2010-01-05 01:10:40 +00:00
DebugInfo.cpp	Use line and column number to distinguish two lexical blocks at the same level.	2010-02-16 21:39:34 +00:00
DomPrinter.cpp	Create Generic DOTGraphTraits Printer/Viewer	2010-01-16 10:56:41 +00:00
IVUsers.cpp	Simplify this code; no need for a custom subclass if it doesn't need	2010-02-14 02:48:58 +00:00
InlineCost.cpp	There are two ways of checking for a given type, for example isa<PointerType>(T)	2010-02-16 11:11:14 +00:00
InstCount.cpp	Change dbgs() back to errs() as Chris requested.	2009-12-23 23:29:28 +00:00
InstructionSimplify.cpp	factor some logic out of instcombine into a new SimplifyAddInst method.	2009-11-27 17:42:22 +00:00
Interval.cpp	Change Pass::print to take a raw ostream instead of std::ostream,	2009-08-23 06:03:38 +00:00
IntervalPartition.cpp	Change Pass::print to take a raw ostream instead of std::ostream,	2009-08-23 06:03:38 +00:00
LazyValueInfo.cpp	Convert debug messages to use dbgs(). Generally this means	2009-12-23 20:43:58 +00:00
LibCallAliasAnalysis.cpp	LibCallAliasAnalysis doesn't use TargetData.	2009-07-31 20:56:29 +00:00
LibCallSemantics.cpp	Remove Value::getNameLen	2009-07-26 08:34:35 +00:00
LiveValues.cpp	Fix "the the" and similar typos.	2010-02-10 16:03:48 +00:00
LoopDependenceAnalysis.cpp	Convert debug messages to use dbgs(). Generally this means	2009-12-23 20:52:41 +00:00
LoopInfo.cpp	Restore dump() methods to Loop and MachineLoop.	2010-01-05 21:08:02 +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	Split critical edges as needed for load PRE.	2010-02-16 19:51:59 +00:00
PHITransAddr.cpp	Change dbgs() back to errs() as Chris requested.	2009-12-23 23:27:15 +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	Convert debug messages to use dbgs(). Generally this means	2009-12-23 21:16:54 +00:00
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	Reapplied r81355 with the problems fixed.	2009-09-16 11:35:50 +00:00
ProfileInfoLoaderPass.cpp	adopt getAdjustedAnalysisPointer in a few more passes.	2010-01-20 20:09:02 +00:00
ProfileVerifierPass.cpp	Convert debug messages to use dbgs(). Generally this means	2009-12-23 22:10:20 +00:00
README.txt	Create a README.txt for lib/Analysis, and add an entry.	2009-09-28 18:38:53 +00:00
ScalarEvolution.cpp	There are two ways of checking for a given type, for example isa<PointerType>(T)	2010-02-16 11:11:14 +00:00
ScalarEvolutionAliasAnalysis.cpp	There are two ways of checking for a given type, for example isa<PointerType>(T)	2010-02-16 11:11:14 +00:00
ScalarEvolutionExpander.cpp	Fix SCEVExpander's existing PHI reuse checking to recognize the	2010-02-17 02:39:31 +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
ValueTracking.cpp	There are two ways of checking for a given type, for example isa<PointerType>(T)	2010-02-16 11:11:14 +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.

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