llvm-6502/lib/Analysis
Sebastian Pop b4164284b5 fix warning
DependenceAnalysis.cpp:1164:32: warning: implicit truncation from 'int' to bitfield changes value from -5 to 3
      [-Wconstant-conversion]
    Result.DV[Level].Direction &= ~Dependence::DVEntry::GT;
                               ^  ~~~~~~~~~~~~~~~~~~~~~~~~

Patch from Preston Briggs <preston.briggs@gmail.com>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165784 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-12 02:04:32 +00:00
..
IPA Now that invoke of an intrinsic is possible (for the llvm.do.nothing intrinsic) 2012-09-26 17:16:01 +00:00
AliasAnalysis.cpp Use the attribute enums to query if a parameter has an attribute. 2012-10-09 21:38:14 +00:00
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp
AliasSetTracker.cpp Move TargetData to DataLayout. 2012-10-08 16:38:25 +00:00
Analysis.cpp dependence analysis 2012-10-11 07:32:34 +00:00
BasicAliasAnalysis.cpp Revert 165732 for further review. 2012-10-11 21:27:41 +00:00
BlockFrequencyInfo.cpp
BranchProbabilityInfo.cpp
CaptureTracking.cpp Give CaptureTracker::shouldExplore a base implementation. Most users want to do 2012-10-08 22:12:48 +00:00
CFGPrinter.cpp
CMakeLists.txt dependence analysis 2012-10-11 07:32:34 +00:00
CodeMetrics.cpp Revert 165732 for further review. 2012-10-11 21:27:41 +00:00
ConstantFolding.cpp Revert 165732 for further review. 2012-10-11 21:27:41 +00:00
DbgInfoPrinter.cpp
DependenceAnalysis.cpp fix warning 2012-10-12 02:04:32 +00:00
DominanceFrontier.cpp Release build: guard dump functions with 2012-09-12 05:06:18 +00:00
DomPrinter.cpp
InlineCost.cpp Revert 165732 for further review. 2012-10-11 21:27:41 +00:00
InstCount.cpp
InstructionSimplify.cpp Revert 165732 for further review. 2012-10-11 21:27:41 +00:00
Interval.cpp Revert 'Fix a typo 'iff' => 'if''. iff is an abreviation of if and only if. See: http://en.wikipedia.org/wiki/If_and_only_if Commit 164767 2012-09-27 10:14:43 +00:00
IntervalPartition.cpp
IVUsers.cpp Move TargetData to DataLayout. 2012-10-08 16:38:25 +00:00
LazyValueInfo.cpp Move TargetData to DataLayout. 2012-10-08 16:38:25 +00:00
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp Move TargetData to DataLayout. 2012-10-08 16:38:25 +00:00
LLVMBuild.txt
Loads.cpp Move TargetData to DataLayout. 2012-10-08 16:38:25 +00:00
LoopDependenceAnalysis.cpp Move TargetData to DataLayout. 2012-10-08 16:38:25 +00:00
LoopInfo.cpp Release build: guard dump functions with 2012-09-12 05:06:18 +00:00
LoopPass.cpp
Makefile
MemDepPrinter.cpp
MemoryBuiltins.cpp Use the attribute enums to query if a function has an attribute. 2012-10-09 21:49:51 +00:00
MemoryDependenceAnalysis.cpp Create enums for the different attributes. 2012-10-09 07:45:08 +00:00
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp Move TargetData to DataLayout. 2012-10-08 16:38:25 +00:00
PathNumbering.cpp
PathProfileInfo.cpp
PathProfileVerifier.cpp
PHITransAddr.cpp Release build: guard dump functions with 2012-09-12 05:06:18 +00:00
PostDominators.cpp
ProfileDataLoader.cpp Clean up ProfileDataLoader a bit. 2012-08-31 12:43:07 +00:00
ProfileDataLoaderPass.cpp Cleanups due to feedback. No functionality change. Patch by Alistair. 2012-08-31 05:18:31 +00:00
ProfileEstimatorPass.cpp
ProfileInfo.cpp Profile: set branch weight metadata with data generated from profiling. 2012-08-28 22:21:25 +00:00
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp
ProfileVerifierPass.cpp
README.txt
RegionInfo.cpp Release build: guard dump functions with 2012-09-12 05:06:18 +00:00
RegionPass.cpp Remove the the block_node_iterator of Region, replace it by the block_iterator. 2012-08-27 13:49:24 +00:00
RegionPrinter.cpp
ScalarEvolution.cpp Move TargetData to DataLayout. 2012-10-08 16:38:25 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp Add a new interface to allow IR-level passes to access codegen-specific information. 2012-10-10 22:04:55 +00:00
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp
Trace.cpp Release build: guard dump functions with 2012-09-12 05:06:18 +00:00
TypeBasedAliasAnalysis.cpp
ValueTracking.cpp Revert 165732 for further review. 2012-10-11 21:27:41 +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))

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