llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-11-06 21:05:51 +00:00

History

Chris Lattner 8ef27511e3 remove LoopVR pass. According to Nick: "LoopVR's logic was copied into ScalarEvolution::getUnsignedRange and ::getSignedRange. Please delete LoopVR." git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83531 91177308-0d34-0410-b5e6-96231b3b80d8		2009-10-08 06:42:44 +00:00
..
IPA	Extend the StartPassTimer and StopPassTimer functions so that the	2009-09-28 00:07:05 +00:00
AliasAnalysis.cpp
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp
AliasSetTracker.cpp
Analysis.cpp
BasicAliasAnalysis.cpp
CaptureTracking.cpp
CFGPrinter.cpp
CMakeLists.txt
ConstantFolding.cpp	Extend ConstantFolding to understand signed overflow variants	2009-10-05 22:53:52 +00:00
DbgInfoPrinter.cpp	Remove std::string uses from DebugInfo interface.	2009-09-29 18:40:58 +00:00
DebugInfo.cpp	Extract subprogram and compile unit information from the debug info attached to an instruction.	2009-10-07 22:04:08 +00:00
InstCount.cpp
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp	Instead of testing whether an instruction dominates the loop preheader,	2009-09-27 15:30:00 +00:00
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
LiveValues.cpp
LoopDependenceAnalysis.cpp
LoopInfo.cpp	Move the dominator verification code out of special code embedded within	2009-09-28 00:27:48 +00:00
LoopPass.cpp	Fix this debug output to handle the case where the loop has been deleted.	2009-09-28 15:40:01 +00:00
Makefile
MallocHelper.cpp	Add PR to this FIXME, looks like I didn't commit this change after all.	2009-10-07 09:22:55 +00:00
MemoryDependenceAnalysis.cpp
PointerTracking.cpp	Introduce and use convenience methods for getting pointer types	2009-10-06 15:40:36 +00:00
PostDominators.cpp
ProfileEstimatorPass.cpp
ProfileInfo.cpp
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp
ProfileVerifierPass.cpp
README.txt	Create a README.txt for lib/Analysis, and add an entry.	2009-09-28 18:38:53 +00:00
ScalarEvolution.cpp	Add a properlyDominates member function to ScalarEvolution.	2009-09-27 15:26:03 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp	Introduce and use convenience methods for getting pointer types	2009-10-06 15:40:36 +00:00
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.

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