llvm-mirror/lib/Analysis
Chris Lattner 2f9b661ab8 Add a minor optimization: if we haven't changed the operands of an
add, there is no need to scan the world to find the same add again.
This invalidates the previous testcase, which wasn't wonderful anyway,
because it needed a run of instcombine to permute the use-lists in 
just the right way to before GVN was run (so it was really fragile).
Not a big loss.

llvm-svn: 90973
2009-12-09 17:27:45 +00:00
..
IPA Remove the AliasAnalysis::getMustAliases method, which is dead. 2009-11-22 16:01:44 +00:00
AliasAnalysis.cpp use the new isNoAlias method to simplify some code, only do an escaping check if 2009-11-23 16:46:41 +00:00
AliasAnalysisCounter.cpp Remove includes of Support/Compiler.h that are no longer needed after the 2009-10-25 06:57:41 +00:00
AliasAnalysisEvaluator.cpp Remove includes of Support/Compiler.h that are no longer needed after the 2009-10-25 06:57:41 +00:00
AliasDebugger.cpp Remove the AliasAnalysis::getMustAliases method, which is dead. 2009-11-22 16:01:44 +00:00
AliasSetTracker.cpp Remove the AliasAnalysis::getMustAliases method, which is dead. 2009-11-22 16:01:44 +00:00
Analysis.cpp Tidy #includes. 2009-08-11 16:02:12 +00:00
BasicAliasAnalysis.cpp move DecomposeGEPExpression out into ValueTracking.cpp 2009-11-26 17:12:50 +00:00
CaptureTracking.cpp Fix a typo in a comment, and adjust SmallSet and SmallVector sizes, 2009-12-09 00:28:42 +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
ConstantFolding.cpp Fix PR5551 by not ignoring the top level constantexpr when 2009-12-04 06:29:29 +00:00
DbgInfoPrinter.cpp Remove VISIBILITY_HIDDEN from class/struct found inside anonymous namespaces. 2009-10-25 06:33:48 +00:00
DebugInfo.cpp Revert 90858 90875 and 90805 for now. 2009-12-08 23:21:45 +00:00
DomPrinter.cpp Remove ShortNames from getNodeLabel in DOTGraphTraits 2009-11-30 12:38:47 +00:00
InlineCost.cpp Add a missing closing parenthesis, and tweak to fit in 80 2009-11-01 19:12:43 +00:00
InstCount.cpp Remove FreeInst. 2009-10-26 23:43:48 +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
IVUsers.cpp enable iv-users simplification by default 2009-11-23 23:25:54 +00:00
LazyValueInfo.cpp typo spotted by duncan. 2009-11-16 03:51:42 +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 remove redundant foward declaration. This function is already in 2009-11-11 00:21:21 +00:00
LoopDependenceAnalysis.cpp remove a few dead insertion methods. 2009-08-24 02:39:26 +00:00
LoopInfo.cpp Teach getSmallConstantTripMultiple about Shl operators. 2009-11-20 01:09:34 +00:00
LoopPass.cpp Fix this debug output to handle the case where the loop has been deleted. 2009-09-28 15:40:01 +00:00
Makefile Removed trailing whitespace from Makefiles. 2009-01-09 16:44:42 +00:00
MemoryBuiltins.cpp Simplify ComputeMultiple so that it doesn't depend on TargetData. 2009-11-18 00:58:27 +00:00
MemoryDependenceAnalysis.cpp enhance NonLocalDepEntry to keep the per-block phi translated address 2009-12-09 07:31:04 +00:00
PHITransAddr.cpp Add a minor optimization: if we haven't changed the operands of an 2009-12-09 17:27:45 +00:00
PointerTracking.cpp remove a bunch of extraneous LLVMContext arguments 2009-11-06 04:27:31 +00:00
PostDominators.cpp Change Pass::print to take a raw ostream instead of std::ostream, 2009-08-23 06:03:38 +00:00
ProfileEstimatorPass.cpp Fix MSVC build. 2009-12-03 13:23:03 +00:00
ProfileInfo.cpp Converted ProfileInfo to template, added more API for ProfileInfo-preserving. 2009-12-03 09:30:12 +00:00
ProfileInfoLoader.cpp Reapplied r81355 with the problems fixed. 2009-09-16 11:35:50 +00:00
ProfileInfoLoaderPass.cpp Use ProfileInfo-API in ProfileInfo Loader and do more assertions. 2009-12-03 11:00:37 +00:00
ProfileVerifierPass.cpp Convert ProfileVerifier to template so it can be used for different types of ProfileInfo. 2009-12-03 12:55:57 +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 Remove dead LLVMContext argument. 2009-11-23 03:26:09 +00:00
ScalarEvolutionAliasAnalysis.cpp Make ScalarEvolutionAliasAnalysis slightly more aggressive, by making an 2009-10-31 14:32:25 +00:00
ScalarEvolutionExpander.cpp Fix a comment typo. 2009-12-04 01:33:04 +00:00
SparsePropagation.cpp rename indbr -> indirectbr to appease the residents of #llvm. 2009-10-28 00:19:10 +00:00
Trace.cpp eliminate the "Value" printing methods that print to a std::ostream. 2009-08-23 04:37:46 +00:00
ValueTracking.cpp Fixed an assertion failure for tracking sext of a vector of integers 2009-12-02 04:59:58 +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.

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