llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-11-07 12:07:17 +00:00

History

Chris Lattner 79fa3cf451 constant fold nasty constant expressions formed by llvm-gcc, wrapping up PR3351. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92410 91177308-0d34-0410-b5e6-96231b3b80d8		2010-01-02 01:22:23 +00:00
..
IPA	Change dbgs() back to errs() for assert messages as Chris requested.	2009-12-23 23:14:41 +00:00
AliasAnalysis.cpp	use the new isNoAlias method to simplify some code, only do an escaping check if	2009-11-23 16:46:41 +00:00
AliasAnalysisCounter.cpp	Change dbgs() back to errs() as Chris requested.	2009-12-23 22:49:57 +00:00
AliasAnalysisEvaluator.cpp	Change dbgs() back to errs() as Chris requested.	2009-12-23 22:49:57 +00:00
AliasDebugger.cpp
AliasSetTracker.cpp	Change dbgs() back to errs() as Chris requested.	2009-12-23 22:49:57 +00:00
Analysis.cpp
BasicAliasAnalysis.cpp
CaptureTracking.cpp
CFGPrinter.cpp
CMakeLists.txt
ConstantFolding.cpp	constant fold nasty constant expressions formed by llvm-gcc,	2010-01-02 01:22:23 +00:00
DbgInfoPrinter.cpp	fix Analysis/DebugInfo.h to not include Metadata.h. Do this	2009-12-31 03:02:08 +00:00
DebugInfo.cpp	fix Analysis/DebugInfo.h to not include Metadata.h. Do this	2009-12-31 03:02:08 +00:00
DomPrinter.cpp
InlineCost.cpp
InstCount.cpp	Change dbgs() back to errs() as Chris requested.	2009-12-23 23:29:28 +00:00
InstructionSimplify.cpp
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp	Convert debug messages to use dbgs(). Generally this means	2009-12-23 20:20:46 +00:00
LazyValueInfo.cpp
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
LiveValues.cpp
LoopDependenceAnalysis.cpp
LoopInfo.cpp
LoopPass.cpp
Makefile
MemoryBuiltins.cpp
MemoryDependenceAnalysis.cpp
PHITransAddr.cpp	Change dbgs() back to errs() as Chris requested.	2009-12-23 23:27:15 +00:00
PointerTracking.cpp
PostDominators.cpp
ProfileEstimatorPass.cpp
ProfileInfo.cpp	Change dbgs() back to errs() for assert messages as Chris requested.	2009-12-23 22:59:29 +00:00
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp	Change dbgs() back to errs() for assert messages as Chris requested.	2009-12-23 23:00:50 +00:00
ProfileVerifierPass.cpp
README.txt
ScalarEvolution.cpp	Remove dump routine and the associated Debug.h from a header. Patch up	2009-12-23 22:58:38 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp
SparsePropagation.cpp
Trace.cpp
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.

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