llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-10-05 07:56:14 +00:00

History

Rafael Espindola 04594aeffa Add r149110 back with a fix for when the vector and the int have the same width. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149151 91177308-0d34-0410-b5e6-96231b3b80d8		2012-01-27 23:33:07 +00:00
..
IPA
AliasAnalysis.cpp
AliasAnalysisCounter.cpp	Remove unnecessary default cases in switches that cover all enum values.	2012-01-10 16:47:17 +00:00
AliasAnalysisEvaluator.cpp	Remove unnecessary default cases in switches that cover all enum values.	2012-01-10 16:47:17 +00:00
AliasDebugger.cpp
AliasSetTracker.cpp
Analysis.cpp
BasicAliasAnalysis.cpp
BlockFrequencyInfo.cpp
BranchProbabilityInfo.cpp
CaptureTracking.cpp	Move includes to the .cpp file.	2012-01-17 22:16:31 +00:00
CFGPrinter.cpp
CMakeLists.txt
ConstantFolding.cpp	Add r149110 back with a fix for when the vector and the int have the same	2012-01-27 23:33:07 +00:00
DbgInfoPrinter.cpp
DebugInfo.cpp	Don't avoid recursing for pointer types, just reference types. Expand on	2012-01-11 00:01:29 +00:00
DIBuilder.cpp	Cleanup these asserts to follow common LLVM style and coding	2012-01-10 18:18:52 +00:00
DominanceFrontier.cpp
DomPrinter.cpp
InlineCost.cpp	Use precomputed BB size instead of BB->size().	2012-01-25 18:54:13 +00:00
InstCount.cpp
InstructionSimplify.cpp
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp
LazyValueInfo.cpp	Remove dead code.	2012-01-18 10:10:28 +00:00
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp
LLVMBuild.txt
Loads.cpp
LoopDependenceAnalysis.cpp	More dead code removal (using -Wunreachable-code)	2012-01-20 21:51:11 +00:00
LoopInfo.cpp
LoopPass.cpp
Makefile
MemDepPrinter.cpp
MemoryBuiltins.cpp
MemoryDependenceAnalysis.cpp	More dead code removal (using -Wunreachable-code)	2012-01-20 21:51:11 +00:00
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp
PathNumbering.cpp
PathProfileInfo.cpp
PathProfileVerifier.cpp
PHITransAddr.cpp	More dead code removal (using -Wunreachable-code)	2012-01-20 21:51:11 +00:00
PostDominators.cpp
ProfileEstimatorPass.cpp
ProfileInfo.cpp
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp
ProfileVerifierPass.cpp
README.txt
RegionInfo.cpp
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp	switch SCEV to use the new ConstantFoldLoadThroughGEPIndices function	2012-01-24 05:49:24 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp	More dead code removal (using -Wunreachable-code)	2012-01-20 21:51:11 +00:00
ScalarEvolutionNormalization.cpp	More dead code removal (using -Wunreachable-code)	2012-01-20 21:51:11 +00:00
SparsePropagation.cpp
Trace.cpp
TypeBasedAliasAnalysis.cpp
ValueTracking.cpp	progress making the world safe to ConstantDataVector. While	2012-01-26 21:37:55 +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))

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