llvm-6502/lib/Analysis
Hans Wennborg b499b73e30 Revert r230280: "Bugfix: SCEVExpander incorrectly marks increment operations as no-wrap"
This caused PR22674, failing this assert:

Instructions.h:2281: llvm::Value* llvm::PHINode::getOperand(unsigned int) const: Assertion `i_nocapture < OperandTraits<PHINode>::operands(this) && "getOperand() out of range!"' failed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230341 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-24 16:19:29 +00:00
..
IPA Analysis: Canonicalize access to function attributes, NFC 2015-02-14 00:12:15 +00:00
AliasAnalysis.cpp [PM] Separate the TargetLibraryInfo object from the immutable pass. 2015-01-15 10:41:28 +00:00
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp
AliasSetTracker.cpp AliasSet: Simplify mergeSetIn 2014-11-19 19:36:18 +00:00
Analysis.cpp Introduce print-memderefs to test isDereferenceablePointer 2015-02-06 01:46:42 +00:00
AssumptionCache.cpp [PM] Actually add the new pass manager support for the assumption cache. 2015-01-22 21:53:09 +00:00
BasicAliasAnalysis.cpp [BasicAA] Try to disambiguate GEPs through arrays of structs into 2015-02-07 17:04:29 +00:00
BlockFrequencyInfo.cpp [PM] Split the LoopInfo object apart from the legacy pass, creating 2015-01-17 14:16:18 +00:00
BlockFrequencyInfoImpl.cpp BFI: Saturate when combining edges to a successor 2014-12-05 19:13:42 +00:00
BranchProbabilityInfo.cpp [PM] Split the LoopInfo object apart from the legacy pass, creating 2015-01-17 14:16:18 +00:00
CaptureTracking.cpp [cleanup] Re-sort all the #include lines in LLVM using 2015-01-14 11:23:27 +00:00
CFG.cpp Standardize {pred,succ,use,user}_empty() 2015-01-13 03:46:47 +00:00
CFGPrinter.cpp
CFLAliasAnalysis.cpp Fixed a bug where CFLAA would crash the compiler. 2015-02-12 03:07:07 +00:00
CGSCCPassManager.cpp [PM] Remove the defunt CGSCC-specific debug flag. 2015-01-13 22:45:13 +00:00
CMakeLists.txt Use ADDITIONAL_HEADER_DIRS in all LLVM CMake projects. 2015-02-11 03:28:02 +00:00
CodeMetrics.cpp [PM] Split the AssumptionTracker immutable pass into two separate APIs: 2015-01-04 12:03:27 +00:00
ConstantFolding.cpp [PM] Move TargetLibraryInfo into the Analysis library. 2015-01-15 02:16:27 +00:00
CostModel.cpp [multiversion] Thread a function argument through all the callers of the 2015-02-01 12:01:35 +00:00
Delinearization.cpp [PM] Split the LoopInfo object apart from the legacy pass, creating 2015-01-17 14:16:18 +00:00
DependenceAnalysis.cpp [PM] Split the LoopInfo object apart from the legacy pass, creating 2015-01-17 14:16:18 +00:00
DominanceFrontier.cpp
DomPrinter.cpp
InstCount.cpp
InstructionSimplify.cpp InstSimplify: simplify 0 / X if nnan and nsz 2015-02-23 18:30:25 +00:00
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp [PM] Split the LoopInfo object apart from the legacy pass, creating 2015-01-17 14:16:18 +00:00
JumpInstrTableInfo.cpp Add Forward Control-Flow Integrity. 2014-11-11 21:08:02 +00:00
LazyCallGraph.cpp Revert r225854: [PM] Move the LazyCallGraph printing functionality to 2015-01-14 00:27:45 +00:00
LazyValueInfo.cpp [PM] Separate the TargetLibraryInfo object from the immutable pass. 2015-01-15 10:41:28 +00:00
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp Unify the two EH personality classification routines I wrote 2015-02-14 00:21:02 +00:00
Lint.cpp [PM] Remove the old 'PassManager.h' header file at the top level of 2015-02-13 10:01:29 +00:00
LLVMBuild.txt Update libdeps since TLI was moved from Target to Analysis in r226078. 2015-01-15 05:21:00 +00:00
Loads.cpp Revert r220349 to re-instate r220277 with a fix for PR21330 -- quite 2014-11-25 08:20:27 +00:00
LoopAccessAnalysis.cpp [LoopAccesses] LAA::getInfo to use const reference for stride parameter 2015-02-24 00:41:59 +00:00
LoopInfo.cpp [PM] Port LoopInfo to the new pass manager, adding both a LoopAnalysis 2015-01-20 10:58:50 +00:00
LoopPass.cpp [PM] Split the LoopInfo object apart from the legacy pass, creating 2015-01-17 14:16:18 +00:00
Makefile
MemDepPrinter.cpp MemDepPrinter: cleanup a few loops (NFC) 2015-02-09 19:49:54 +00:00
MemDerefPrinter.cpp MemDerefPrinter: Require DataLayoutPass for higher accuracy 2015-02-09 21:50:03 +00:00
MemoryBuiltins.cpp [PM] Move TargetLibraryInfo into the Analysis library. 2015-01-15 02:16:27 +00:00
MemoryDependenceAnalysis.cpp Revert 229175 2015-02-15 19:07:31 +00:00
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp
PHITransAddr.cpp [PM] Split the AssumptionTracker immutable pass into two separate APIs: 2015-01-04 12:03:27 +00:00
PostDominators.cpp
PtrUseVisitor.cpp Update SetVector to rely on the underlying set's insert to return a pair<iterator, bool> 2014-11-19 07:49:26 +00:00
README.txt
RegionInfo.cpp [cleanup] Re-sort all the #include lines in LLVM using 2015-01-14 11:23:27 +00:00
RegionPass.cpp [cleanup] Re-sort all the #include lines in LLVM using 2015-01-14 11:23:27 +00:00
RegionPrinter.cpp
ScalarEvolution.cpp Fix bug 22641 2015-02-24 01:02:42 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp Revert r230280: "Bugfix: SCEVExpander incorrectly marks increment operations as no-wrap" 2015-02-24 16:19:29 +00:00
ScalarEvolutionNormalization.cpp
ScopedNoAliasAA.cpp [cleanup] Re-sort all the #include lines in LLVM using 2015-01-14 11:23:27 +00:00
SparsePropagation.cpp
StratifiedSets.h Update SetVector to rely on the underlying set's insert to return a pair<iterator, bool> 2014-11-19 07:49:26 +00:00
TargetLibraryInfo.cpp [PM] Rework how the TargetLibraryInfo pass integrates with the new pass 2015-01-24 02:06:09 +00:00
TargetTransformInfo.cpp Prevent hoisting fmul from THEN/ELSE to IF if there is fmsub/fmadd opportunity. 2015-02-23 19:15:16 +00:00
Trace.cpp
TypeBasedAliasAnalysis.cpp Correctly combine alias.scope metadata by a union instead of intersecting 2015-02-08 17:07:14 +00:00
ValueTracking.cpp ValueTracking: Make isBytewiseValue simpler and more powerful at the same time. 2015-02-07 19:29:02 +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))

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