llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-11-04 06:09:05 +00:00

History

Dan Gohman e059ee832c Don't back past debug info intrinsics; SCEVExpander's strategy for ignoring debug info intrinsics everywhere else is to advance past them, and it needs to be consistent. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99332 91177308-0d34-0410-b5e6-96231b3b80d8		2010-03-23 21:53:22 +00:00
..
IPA	backing out r99170 because it still fails on clang-x86_64-darwin10-fnt	2010-03-22 09:11:00 +00:00
AliasAnalysis.cpp
AliasAnalysisCounter.cpp	Fix a missing newline in debug output.	2010-03-01 17:42:55 +00:00
AliasAnalysisEvaluator.cpp	There are two ways of checking for a given type, for example isa<PointerType>(T)	2010-02-16 11:11:14 +00:00
AliasDebugger.cpp
AliasSetTracker.cpp
Analysis.cpp
BasicAliasAnalysis.cpp	There are two ways of checking for a given type, for example isa<PointerType>(T)	2010-02-16 11:11:14 +00:00
CaptureTracking.cpp	There are two ways of checking for a given type, for example isa<PointerType>(T)	2010-02-16 11:11:14 +00:00
CFGPrinter.cpp
CMakeLists.txt
ConstantFolding.cpp	FP16 constfolding	2010-03-19 00:36:35 +00:00
DbgInfoPrinter.cpp
DebugInfo.cpp	Start using DIFile. See updated SourceLevelDebugging.html for more information.	2010-03-09 00:44:10 +00:00
DomPrinter.cpp
InlineCost.cpp	Treat copysignl like the other copysign functions.	2010-03-15 14:01:44 +00:00
InstCount.cpp
InstructionSimplify.cpp	fix incorrect folding of icmp with undef, PR6481.	2010-03-03 19:46:03 +00:00
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp	Spelling fixes.	2010-03-01 17:49:51 +00:00
LazyValueInfo.cpp
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
LiveValues.cpp	Fix "the the" and similar typos.	2010-02-10 16:03:48 +00:00
LoopDependenceAnalysis.cpp	Define placement new wrappers for BumpPtrAllocator and	2010-03-18 18:49:47 +00:00
LoopInfo.cpp	Add a DominatorTree argument to isLCSSA so that it doesn't have to	2010-03-10 19:38:49 +00:00
LoopPass.cpp
Makefile
MemoryBuiltins.cpp	Fix "the the" and similar typos.	2010-02-10 16:03:48 +00:00
MemoryDependenceAnalysis.cpp	Reapply r97010, the speculative revert failed.	2010-02-24 08:48:04 +00:00
PHITransAddr.cpp	Reapply r97010, the speculative revert failed.	2010-02-24 08:48:04 +00:00
PointerTracking.cpp	There are two ways of checking for a given type, for example isa<PointerType>(T)	2010-02-16 11:11:14 +00:00
PostDominators.cpp
ProfileEstimatorPass.cpp
ProfileInfo.cpp
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp
ProfileVerifierPass.cpp
README.txt
ScalarEvolution.cpp	Define placement new wrappers for BumpPtrAllocator and	2010-03-18 18:49:47 +00:00
ScalarEvolutionAliasAnalysis.cpp	Add a comment.	2010-03-01 17:56:04 +00:00
ScalarEvolutionExpander.cpp	Don't back past debug info intrinsics; SCEVExpander's strategy	2010-03-23 21:53:22 +00:00
SparsePropagation.cpp
Trace.cpp
ValueTracking.cpp	Fix a typo in ValueTracking that's causing instcombine to delete needed shift instructions.	2010-03-13 02:20:29 +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.

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