llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-11-03 14:08:57 +00:00

History

Silviu Baranga 5b50110192 Cleanup after r241809 - remove uncessary call to std::sort Summary: The iteration order within a member of DepCands is deterministic and therefore we don't have to sort the accesses within a member. We also don't have to copy the indices of the pointers into a vector, since we can iterate over the members of the class. Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D11145 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242033 91177308-0d34-0410-b5e6-96231b3b80d8		2015-07-13 14:48:24 +00:00
..
IPA	[PM/AA] Completely remove the AliasAnalysis::copyValue interface.	2015-07-11 04:39:00 +00:00
AliasAnalysis.cpp	[PM/AA] Completely remove the AliasAnalysis::copyValue interface.	2015-07-11 04:39:00 +00:00
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp	[PM/AA] Completely remove the AliasAnalysis::copyValue interface.	2015-07-11 04:39:00 +00:00
AliasSetTracker.cpp	[PM/AA] Completely remove the AliasAnalysis::copyValue interface.	2015-07-11 04:39:00 +00:00
Analysis.cpp
AssumptionCache.cpp
BasicAliasAnalysis.cpp	Revert r241981 "Revert "Revert r236894 "[BasicAA] Fix zext & sext handling"""	2015-07-13 13:50:55 +00:00
BlockFrequencyInfo.cpp
BlockFrequencyInfoImpl.cpp
BranchProbabilityInfo.cpp
CaptureTracking.cpp
CFG.cpp
CFGPrinter.cpp
CFLAliasAnalysis.cpp
CGSCCPassManager.cpp
CMakeLists.txt	Move VectorUtils from Transforms to Analysis to correct layering violation	2015-06-26 18:02:52 +00:00
CodeMetrics.cpp
ConstantFolding.cpp	Allow constfolding of llvm.sin.* and llvm.cos.* intrinsics	2015-07-08 03:55:47 +00:00
CostModel.cpp
Delinearization.cpp	Move delinearization from SCEVAddRecExpr to ScalarEvolution	2015-06-29 14:42:48 +00:00
DependenceAnalysis.cpp	Move delinearization from SCEVAddRecExpr to ScalarEvolution	2015-06-29 14:42:48 +00:00
DivergenceAnalysis.cpp
DominanceFrontier.cpp
DomPrinter.cpp
InstCount.cpp
InstructionSimplify.cpp	[InstSimplify] Teach InstSimplify how to simplify extractelement	2015-07-13 01:15:53 +00:00
Interval.cpp
IntervalPartition.cpp
IteratedDominanceFrontier.cpp
IVUsers.cpp	[LSR] don't attempt to promote ephemeral values to indvars	2015-07-13 03:28:53 +00:00
LazyCallGraph.cpp
LazyValueInfo.cpp
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp
LLVMBuild.txt
Loads.cpp	Take alignment into account in isSafeToLoadUnconditionally	2015-06-25 12:18:43 +00:00
LoopAccessAnalysis.cpp	Cleanup after r241809 - remove uncessary call to std::sort	2015-07-13 14:48:24 +00:00
LoopInfo.cpp
LoopPass.cpp
Makefile
MemDepPrinter.cpp
MemDerefPrinter.cpp
MemoryBuiltins.cpp
MemoryDependenceAnalysis.cpp
MemoryLocation.cpp
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp	[PM/AA] Completely remove the AliasAnalysis::copyValue interface.	2015-07-11 04:39:00 +00:00
PHITransAddr.cpp
PostDominators.cpp
PtrUseVisitor.cpp
README.txt
RegionInfo.cpp
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp	Move delinearization from SCEVAddRecExpr to ScalarEvolution	2015-06-29 14:42:48 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp
ScalarEvolutionNormalization.cpp
ScopedNoAliasAA.cpp
SparsePropagation.cpp
StratifiedSets.h
TargetLibraryInfo.cpp
TargetTransformInfo.cpp	Make TargetTransformInfo keeping a reference to the Module DataLayout	2015-07-09 02:08:42 +00:00
Trace.cpp
TypeBasedAliasAnalysis.cpp
ValueTracking.cpp	IR: Do not consider available_externally linkage to be linker-weak.	2015-07-05 20:52:35 +00:00
VectorUtils.cpp	[InstSimplify] Teach InstSimplify how to simplify extractelement	2015-07-13 01:15:53 +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.

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

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))

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