llvm/lib/Analysis
Bob Wilson 6a09098cca Remove code to saturate profile counts.
We may need to change the way profile counter values are stored, but
saturation is the wrong thing to do.  Just remove it for now.

Patch by Alastair Murray!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166938 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-29 17:27:39 +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 Persuade GCC that there is nothing worth warning about here (there isn't). 2012-02-05 14:20:11 +00:00
AliasAnalysisEvaluator.cpp Remove unnecessary default cases in switches that cover all enum values. 2012-01-10 16:47:17 +00:00
AliasDebugger.cpp
AliasSetTracker.cpp Move TargetData to DataLayout. 2012-10-08 16:38:25 +00:00
Analysis.cpp Remove LoopDependenceAnalysis. 2012-10-26 20:25:01 +00:00
BasicAliasAnalysis.cpp Resubmit the changes to llvm core to update the functions to support different pointer sizes on a per address space basis. 2012-10-15 16:24:29 +00:00
BlockFrequencyInfo.cpp Add some constantness to BranchProbabilityInfo and BlockFrequnencyInfo. 2011-12-20 20:03:10 +00:00
BranchProbabilityInfo.cpp BranchProb: modify the definition of an edge in BranchProbabilityInfo to handle 2012-08-24 18:14:27 +00:00
CaptureTracking.cpp Give CaptureTracker::shouldExplore a base implementation. Most users want to do 2012-10-08 22:12:48 +00:00
CFGPrinter.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
CMakeLists.txt Remove LoopDependenceAnalysis. 2012-10-26 20:25:01 +00:00
CodeMetrics.cpp Resubmit the changes to llvm core to update the functions to support different pointer sizes on a per address space basis. 2012-10-15 16:24:29 +00:00
ConstantFolding.cpp Add some cleanup to the DataLayout changes requested by Chandler. 2012-10-24 18:36:13 +00:00
DbgInfoPrinter.cpp Move lib/Analysis/DebugInfo.cpp to lib/VMCore/DebugInfo.cpp and 2012-06-28 00:05:13 +00:00
DependenceAnalysis.cpp DependenceAnalysis: Push #includes down into the implementation. 2012-10-25 16:15:22 +00:00
DominanceFrontier.cpp Release build: guard dump functions with 2012-09-12 05:06:18 +00:00
DomPrinter.cpp remove the blank line from previous ci. 2012-02-04 03:18:47 +00:00
InlineCost.cpp Add some cleanup to the DataLayout changes requested by Chandler. 2012-10-24 18:36:13 +00:00
InstCount.cpp
InstructionSimplify.cpp Add some cleanup to the DataLayout changes requested by Chandler. 2012-10-24 18:36:13 +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 Hoist out some work done inside a loop doing a linear scan over all 2012-10-26 04:43:47 +00:00
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp Add in support for getIntPtrType to get the pointer type based on the address space. 2012-10-24 15:52:52 +00:00
LLVMBuild.txt LLVMBuild: Introduce a common section which currently has a list of the 2011-12-12 22:45:54 +00:00
Loads.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 Enable the new LoopInfo algorithm by default. 2012-06-26 04:11:38 +00:00
Makefile
MemDepPrinter.cpp Mark some static arrays as const. 2012-05-24 06:35:32 +00:00
MemoryBuiltins.cpp Add in support for getIntPtrType to get the pointer type based on the address space. 2012-10-24 15:52:52 +00:00
MemoryDependenceAnalysis.cpp Ignore unreachable blocks when doing memory dependence analysis on non-local 2012-10-23 18:37:11 +00:00
ModuleDebugInfoPrinter.cpp Move lib/Analysis/DebugInfo.cpp to lib/VMCore/DebugInfo.cpp and 2012-06-28 00:05:13 +00:00
NoAliasAnalysis.cpp Move TargetData to DataLayout. 2012-10-08 16:38:25 +00:00
PathNumbering.cpp Move llvm/Support/TypeBuilder.h -> llvm/TypeBuilder.h. This completes 2012-07-15 23:45:24 +00:00
PathProfileInfo.cpp
PathProfileVerifier.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
PHITransAddr.cpp Release build: guard dump functions with 2012-09-12 05:06:18 +00:00
PostDominators.cpp
ProfileDataLoader.cpp Remove code to saturate profile counts. 2012-10-29 17:27:39 +00:00
ProfileDataLoaderPass.cpp Cleanups due to feedback. No functionality change. Patch by Alistair. 2012-08-31 05:18:31 +00:00
ProfileEstimatorPass.cpp Fix floating-point divide by zero, in a case where the value was not going to be used anyway. 2012-08-24 00:31:45 +00:00
ProfileInfo.cpp Profile: set branch weight metadata with data generated from profiling. 2012-08-28 22:21:25 +00:00
ProfileInfoLoader.cpp Remove unused private member variables uncovered by the recent changes to clang's -Wunused-private-field. 2012-07-20 22:05:57 +00:00
ProfileInfoLoaderPass.cpp Round 2 of dead private variable removal. 2012-06-06 19:47:08 +00:00
ProfileVerifierPass.cpp Move code into anonymous namespaces. 2011-11-26 23:01:57 +00:00
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 Rename the Region::block_iterator to Region::block_node_iterator, and 2012-05-04 20:55:23 +00:00
ScalarEvolution.cpp SCEV validator: Ignore CouldNotCompute/undef on both sides. This is mostly noise and blocks finding more severe bugs. 2012-10-27 11:36:07 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp Add in support for getIntPtrType to get the pointer type based on the address space. 2012-10-24 15:52:52 +00:00
ScalarEvolutionNormalization.cpp More dead code removal (using -Wunreachable-code) 2012-01-20 21:51:11 +00:00
SparsePropagation.cpp Taken into account Duncan's comments for r149481 dated by 2nd Feb 2012: 2012-03-08 07:06:20 +00:00
Trace.cpp Release build: guard dump functions with 2012-09-12 05:06:18 +00:00
TypeBasedAliasAnalysis.cpp
ValueTracking.cpp Fix a crash in SimpliftDemandedBits of vectors of pointers. 2012-10-26 17:17:05 +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))

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