llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-21 00:32:23 +00:00

History

Dan Gohman 615da1a9bc Teach BasicAA to return PartialAlias in cases where both pointers are pointing to the same object, one pointer is accessing the entire object, and the other is access has a non-zero size. This prevents TBAA from kicking in and saying NoAlias in such cases. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123775 91177308-0d34-0410-b5e6-96231b3b80d8		2011-01-18 21:16:06 +00:00
..
IPA	Use the new addEscapingValue callback to update GlobalsModRef when GVN adds PHIs of GEPs. For the moment,	2011-01-03 23:51:43 +00:00
AliasAnalysis.cpp	Stub out a new updating interface to AliasAnalysis, allowing stateful analyses to be informed when	2011-01-03 21:38:41 +00:00
AliasAnalysisCounter.cpp	Teach AliasAnalysisCounter about PartialAlias.	2010-12-10 19:53:05 +00:00
AliasAnalysisEvaluator.cpp	Teach AliasAnalysisEvaluator about PartialAlias.	2010-12-10 19:52:40 +00:00
AliasDebugger.cpp	Extend the AliasAnalysis::pointsToConstantMemory interface to allow it	2010-11-08 16:45:26 +00:00
AliasSetTracker.cpp	Update this code to handle PartialAlias as MayAlias.	2010-12-10 19:40:47 +00:00
Analysis.cpp	Move DominanceFrontier from VMCore to Analysis.	2011-01-18 06:06:27 +00:00
BasicAliasAnalysis.cpp	Teach BasicAA to return PartialAlias in cases where both pointers	2011-01-18 21:16:06 +00:00
CaptureTracking.cpp	VAArg doesn't capture its operand.	2010-11-09 20:09:35 +00:00
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	Move DominanceFrontier from VMCore to Analysis.	2011-01-18 06:06:27 +00:00
ConstantFolding.cpp	fix PR8983, a broken assertion.	2011-01-16 03:43:53 +00:00
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	Add support to create class type.	2010-12-08 20:18:20 +00:00
DIBuilder.cpp	Use type's file info while describing inheritance relationship.	2010-12-08 21:46:37 +00:00
DominanceFrontier.cpp	Move DominanceFrontier from VMCore to Analysis.	2011-01-18 06:06:27 +00:00
DomPrinter.cpp	split dom frontier handling stuff out to its own DominanceFrontier header,	2011-01-02 22:09:33 +00:00
InlineCost.cpp	Now using a variant of the existing inlining heuristics to decide whether to create a given specialization of a function in PartialSpecialization. If the total performance bonus across all callsites passing the same constant exceeds the specialization cost, we create the specialization.	2010-10-09 22:06:36 +00:00
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	For completeness, generalize the (X + Y) - Y -> X transform and add X - (X + 1) -> -1.	2011-01-18 11:50:19 +00:00
Interval.cpp
IntervalPartition.cpp	Now with fewer extraneous semicolons!	2010-10-07 22:25:06 +00:00
IVUsers.cpp	split dom frontier handling stuff out to its own DominanceFrontier header,	2011-01-02 22:09:33 +00:00
LazyValueInfo.cpp	Teach LazyValueInfo that allocas aren't NULL. Over all of llvm-test, this saves	2011-01-15 09:16:12 +00:00
LibCallAliasAnalysis.cpp	Now with fewer extraneous semicolons!	2010-10-07 22:25:06 +00:00
LibCallSemantics.cpp	Thread const correctness through a bunch of AliasAnalysis interfaces and	2010-08-03 21:48:53 +00:00
Lint.cpp	Move Value::getUnderlyingObject to be a standalone	2010-12-15 20:02:24 +00:00
LiveValues.cpp	split dom frontier handling stuff out to its own DominanceFrontier header,	2011-01-02 22:09:33 +00:00
Loads.cpp	Move Value::getUnderlyingObject to be a standalone	2010-12-15 20:02:24 +00:00
LoopDependenceAnalysis.cpp	split dom frontier handling stuff out to its own DominanceFrontier header,	2011-01-02 22:09:33 +00:00
LoopInfo.cpp	Fix typo pointed out by Trevor Harmon.	2010-11-13 12:16:27 +00:00
LoopPass.cpp	zap dead code.	2010-09-04 18:12:00 +00:00
Makefile	make -fno-rtti the default unless a directory builds with REQUIRES_RTTI.	2010-01-24 20:43:08 +00:00
MemDepPrinter.cpp	Add helper functions for computing the Location of load, store,	2010-11-11 21:50:19 +00:00
MemoryBuiltins.cpp	minor enhancement to llvm::isFreeCall API: return CallInst; no functional change	2010-06-23 21:51:12 +00:00
MemoryDependenceAnalysis.cpp	Revert r123207: "Turn on memdep's verifyRemoved() in an attempt to smoke out the cause of our gcc bootstrap miscompare."	2011-01-11 04:05:39 +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	Use the new addEscapingValue callback to update GlobalsModRef when GVN adds PHIs of GEPs. For the moment,	2011-01-03 23:51:43 +00:00
PHITransAddr.cpp	split dom frontier handling stuff out to its own DominanceFrontier header,	2011-01-02 22:09:33 +00:00
PostDominators.cpp	split dom frontier handling stuff out to its own DominanceFrontier header,	2011-01-02 22:09:33 +00:00
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	When checking whether the special handling for an addrec increment which	2010-04-26 21:46:36 +00:00
RegionInfo.cpp	Add single entry / single exit accessors.	2011-01-13 23:18:04 +00:00
RegionPass.cpp	Remove useless dynamic_cast<>().	2010-12-12 21:58:28 +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	some comment improvements.	2011-01-11 17:11:59 +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	Introduce memoization for ScalarEvolution dominates and properlyDominates	2010-11-18 00:34:22 +00:00
ScalarEvolutionNormalization.cpp	Disable the asserts that check that normalization is perfectly	2010-09-03 22:12:56 +00:00
SparsePropagation.cpp
Trace.cpp
TypeBasedAliasAnalysis.cpp	Update a comment.	2010-12-16 02:55:10 +00:00
ValueTracking.cpp	fix an off-by-one bug that caused a crash analyzing	2011-01-04 18:19:15 +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))

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