llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-30 17:33:24 +00:00

History

Dan Gohman cd5c123a1d Teach memdep to use pointsToConstantMemory to determine that loads from constant memory don't alias any stores. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117636 91177308-0d34-0410-b5e6-96231b3b80d8		2010-10-29 01:14:04 +00:00
..
IPA	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
AliasAnalysis.cpp	Update comments; BasicAA is no longer necessarily the end of the chain.	2010-10-25 16:29:52 +00:00
AliasAnalysisCounter.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
AliasAnalysisEvaluator.cpp	Reapply r116831 and r116839, converting AliasAnalysis to use	2010-10-19 22:54:46 +00:00
AliasDebugger.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
AliasSetTracker.cpp	Reapply r116831 and r116839, converting AliasAnalysis to use	2010-10-19 22:54:46 +00:00
Analysis.cpp
BasicAliasAnalysis.cpp	Move NoAA out of BasicAliasAnalysis.cpp into its own file, now that	2010-10-19 23:09:08 +00:00
CaptureTracking.cpp
CFGPrinter.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
CMakeLists.txt	Add RegionPass support.	2010-10-20 01:54:44 +00:00
ConstantFolding.cpp
DbgInfoPrinter.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
DebugInfo.cpp
DomPrinter.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
InlineCost.cpp
InstCount.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
InstructionSimplify.cpp
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
LazyValueInfo.cpp
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp	Reapply r116831 and r116839, converting AliasAnalysis to use	2010-10-19 22:54:46 +00:00
LiveValues.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
Loads.cpp	Reapply r116831 and r116839, converting AliasAnalysis to use	2010-10-19 22:54:46 +00:00
LoopDependenceAnalysis.cpp
LoopInfo.cpp
LoopPass.cpp
Makefile
MemDepPrinter.cpp	Memdep says that an instruction clobbers itself	2010-10-20 22:37:41 +00:00
MemoryBuiltins.cpp
MemoryDependenceAnalysis.cpp	Teach memdep to use pointsToConstantMemory to determine that loads	2010-10-29 01:14:04 +00:00
ModuleDebugInfoPrinter.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
NoAliasAnalysis.cpp	Move NoAA out of BasicAliasAnalysis.cpp into its own file, now that	2010-10-19 23:09:08 +00:00
PHITransAddr.cpp
PostDominators.cpp
ProfileEstimatorPass.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
ProfileInfo.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
ProfileVerifierPass.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
README.txt
RegionInfo.cpp	Make some symbols static, move classes into anonymous namespaces.	2010-10-22 17:35:07 +00:00
RegionPass.cpp	Add RegionPass support.	2010-10-20 01:54:44 +00:00
RegionPrinter.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
ScalarEvolution.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
ScalarEvolutionAliasAnalysis.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
ScalarEvolutionExpander.cpp
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp
Trace.cpp
TypeBasedAliasAnalysis.cpp	Support TBAA attachments on calls. This is somewhat experimental.	2010-10-25 21:38:20 +00:00
ValueTracking.cpp

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))

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