llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-18 10:31:57 +00:00

History

Benjamin Kramer baca5334db InstSimplify: Fold equality comparisons between non-inbounds GEPs. Overflow doesn't affect the correctness of equalities. Computing this is cheap, we just reuse the computation for the inbounds case and try to peel of more non-inbounds GEPs. This pattern is unlikely to ever appear in code generated by Clang, but SCEV occasionally produces it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191200 91177308-0d34-0410-b5e6-96231b3b80d8		2013-09-23 14:16:38 +00:00
..
IPA	Disable inlining between sanitized and non-sanitized functions.	2013-08-08 08:22:39 +00:00
AliasAnalysis.cpp	Reimplement isPotentiallyReachable to make nocapture deduction much stronger.	2013-07-27 01:24:00 +00:00
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp
AliasSetTracker.cpp	In AliasSetTracker, do not change the alias set to "mod/ref" when adding	2013-09-12 20:15:50 +00:00
Analysis.cpp	This patch breaks up Wrap.h so that it does not have to include all of	2013-05-01 20:59:00 +00:00
BasicAliasAnalysis.cpp	Remove trailing spaces.	2013-08-24 14:16:00 +00:00
BlockFrequencyInfo.cpp	BlockFrequency: Bump up the entry frequency a bit.	2013-06-25 13:34:40 +00:00
BranchProbabilityInfo.cpp	Use SmallVectorImpl::iterator/const_iterator instead of SmallVector to avoid specifying the vector size.	2013-07-04 01:31:24 +00:00
CaptureTracking.cpp	Extend 'readonly' and 'readnone' to work on function arguments as well as	2013-07-06 00:29:58 +00:00
CFG.cpp	Add some constantness.	2013-08-20 23:04:15 +00:00
CFGPrinter.cpp
CMakeLists.txt	Also update CMakeLists.txt for r187283.	2013-07-27 01:25:51 +00:00
CodeMetrics.cpp
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
DomPrinter.cpp
InstCount.cpp
InstructionSimplify.cpp	InstSimplify: Fold equality comparisons between non-inbounds GEPs.	2013-09-23 14:16:38 +00:00
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp
LazyValueInfo.cpp	Use SmallVectorImpl::iterator/const_iterator instead of SmallVector to avoid specifying the vector size.	2013-07-04 01:31:24 +00:00
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp	Fix lint assert on integer vector division	2013-08-26 23:29:33 +00:00
LLVMBuild.txt
Loads.cpp
LoopInfo.cpp	Add 'const' qualifiers to static const char* variables.	2013-07-16 01:17:10 +00:00
LoopPass.cpp	Comment: try to clarify loop iteration order.	2013-07-20 23:10:31 +00:00
Makefile
MemDepPrinter.cpp
MemoryBuiltins.cpp	Treat nothrow forms of ::operator delete and ::operator delete[] as	2013-07-21 23:11:42 +00:00
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
PathNumbering.cpp
PathProfileInfo.cpp
PathProfileVerifier.cpp
PHITransAddr.cpp
PostDominators.cpp
ProfileDataLoader.cpp	Use SmallVectorImpl& instead of SmallVector to avoid repeating small vector size.	2013-07-14 04:42:23 +00:00
ProfileDataLoaderPass.cpp
ProfileEstimatorPass.cpp	Use SmallVectorImpl::iterator/const_iterator instead of SmallVector to avoid specifying the vector size.	2013-07-04 01:31:24 +00:00
ProfileInfo.cpp
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp
ProfileVerifierPass.cpp
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	Teach ScalarEvolution about pointer address spaces	2013-09-10 19:55:24 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp	Teach ScalarEvolution about pointer address spaces	2013-09-10 19:55:24 +00:00
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp
TargetTransformInfo.cpp	Costmodel: Add support for horizontal vector reductions	2013-09-17 18:06:50 +00:00
Trace.cpp
TypeBasedAliasAnalysis.cpp	TBAA: add isTBAAVtableAccess to MDNode so clients can call the function	2013-09-06 22:47:05 +00:00
ValueTracking.cpp	Fix assert with GEP ptr vector indexing structs	2013-08-19 21:43:16 +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))

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