llvm-6502

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

History

Duncan Sands 291bb70d93 Remove DIFactory. Patch by Devang. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126871 91177308-0d34-0410-b5e6-96231b3b80d8		2011-03-02 20:30:37 +00:00
..
IPA
AliasAnalysis.cpp
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp
AliasSetTracker.cpp
Analysis.cpp	Delete the LiveValues pass. I won't get get back to the project it	2011-02-28 19:37:59 +00:00
BasicAliasAnalysis.cpp
CaptureTracking.cpp
CFGPrinter.cpp
CMakeLists.txt	Unbreak CMake build.	2011-03-01 00:02:51 +00:00
ConstantFolding.cpp	convert ConstantVector::get to use ArrayRef.	2011-02-15 00:14:00 +00:00
DbgInfoPrinter.cpp	Move DbgInfoPrinter specific utlities inside DbgInfoPrinter.cpp	2011-02-15 17:36:11 +00:00
DebugInfo.cpp	Remove DIFactory. Patch by Devang.	2011-03-02 20:30:37 +00:00
DIBuilder.cpp	Today, the language front ends produces llvm.dbg.* intrinsics, used to encode arguments' debug info, in order any way, most of the times. However, if a front end mix-n-matches llvm.dbg.declare and llvm.dbg.value intrinsics to encode debug info for arguments then code generator needs a way to find argument order.	2011-03-01 22:58:13 +00:00
DominanceFrontier.cpp
DomPrinter.cpp
InlineCost.cpp	Remove premature optimization that avoided calculating argument weights	2011-02-06 21:27:46 +00:00
InstCount.cpp
InstructionSimplify.cpp	Optimize "icmp pred (urem X, Y), Y" --> true/false depending on pred. There's	2011-03-01 08:15:50 +00:00
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp
LazyValueInfo.cpp
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp
Loads.cpp
LoopDependenceAnalysis.cpp
LoopInfo.cpp
LoopPass.cpp
Makefile
MemDepPrinter.cpp
MemoryBuiltins.cpp
MemoryDependenceAnalysis.cpp
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp
PathNumbering.cpp	Implementation of path profiling.	2011-01-29 01:09:53 +00:00
PathProfileInfo.cpp	Implementation of path profiling.	2011-01-29 01:09:53 +00:00
PathProfileVerifier.cpp	Implementation of path profiling.	2011-01-29 01:09:53 +00:00
PHITransAddr.cpp
PostDominators.cpp
ProfileEstimatorPass.cpp
ProfileInfo.cpp
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp
ProfileVerifierPass.cpp
README.txt
RegionInfo.cpp
RegionPass.cpp
RegionPrinter.cpp	RegionPrinter: Ignore back edges when layouting the graph	2011-02-27 04:11:07 +00:00
ScalarEvolution.cpp	teach SCEV that the scale and addition of an inbounds gep don't NSW.	2011-02-13 03:14:49 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp	Don't re-use existing addrec expansions if they contain casts.	2011-03-02 01:34:10 +00:00
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp
Trace.cpp
TypeBasedAliasAnalysis.cpp
ValueTracking.cpp	Fix comment.	2011-02-28 09:18:11 +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))

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