llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-10-04 16:01:46 +00:00

History

Matt Arsenault 4784bb6f44 Fix creating bitcasts between address spaces in SCEV. The test before wasn't successfully testing this since it was missing the datalayout piece to change the size of the second address space. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193102 91177308-0d34-0410-b5e6-96231b3b80d8		2013-10-21 18:41:10 +00:00
..
IPA
AliasAnalysis.cpp
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp	Move all of the header files which are involved in modelling the LLVM IR	2013-01-02 11:36:10 +00:00
AliasSetTracker.cpp
Analysis.cpp	Remove the very substantial, largely unmaintained legacy PGO	2013-10-02 15:42:23 +00:00
BasicAliasAnalysis.cpp	Use type helper functions	2013-09-27 22:18:51 +00:00
BlockFrequencyInfo.cpp
BranchProbabilityInfo.cpp
CaptureTracking.cpp
CFG.cpp
CFGPrinter.cpp
CMakeLists.txt	Remove the very substantial, largely unmaintained legacy PGO	2013-10-02 15:42:23 +00:00
CodeMetrics.cpp	Begin fleshing out an interface in TTI for modelling the costs of	2013-01-22 11:26:02 +00:00
ConstantFolding.cpp	Fix a constant folding address space place I missed.	2013-09-17 23:23:16 +00:00
CostModel.cpp	Move variable into assert to avoid unused variable warning.	2013-09-17 21:13:57 +00:00
DependenceAnalysis.cpp	Remove extraneous semicolon.	2013-08-06 16:40:40 +00:00
DominanceFrontier.cpp	Use the new script to sort the includes of every file under lib.	2012-12-03 16:50:05 +00:00
DomPrinter.cpp
InstCount.cpp	Move all of the header files which are involved in modelling the LLVM IR	2013-01-02 11:36:10 +00:00
InstructionSimplify.cpp	Teach MemoryBuiltins and InstructionSimplify that operator new never returns NULL.	2013-09-24 16:37:51 +00:00
Interval.cpp	Move all of the header files which are involved in modelling the LLVM IR	2013-01-02 11:36:10 +00:00
IntervalPartition.cpp
IVUsers.cpp
LazyValueInfo.cpp
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp
LLVMBuild.txt	LLVMBuild: Introduce a common section which currently has a list of the	2011-12-12 22:45:54 +00:00
Loads.cpp
LoopInfo.cpp
LoopPass.cpp
Makefile
MemDepPrinter.cpp
MemoryBuiltins.cpp
MemoryDependenceAnalysis.cpp	Fix xemacs mode line, don't put them in .cpp files (just header files). No	2013-06-10 23:10:59 +00:00
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp
PHITransAddr.cpp
PostDominators.cpp	Move all of the header files which are involved in modelling the LLVM IR	2013-01-02 11:36:10 +00:00
PtrUseVisitor.cpp
README.txt
RegionInfo.cpp	Reorder headers according to lint.	2013-08-21 21:14:19 +00:00
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp	Fix creating bitcasts between address spaces in SCEV.	2013-10-21 18:41:10 +00:00
ScalarEvolutionAliasAnalysis.cpp	Use the new script to sort the includes of every file under lib.	2012-12-03 16:50:05 +00:00
ScalarEvolutionExpander.cpp
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp
TargetTransformInfo.cpp
Trace.cpp
TypeBasedAliasAnalysis.cpp	TBAA: try to fix the dragonegg bots.	2013-09-27 22:59:21 +00:00
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.

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

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))

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