llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-11-04 22:07:27 +00:00

History

Jakob Stoklund Olesen 1f386c4ce1 Don't try to constant fold libm functions with non-finite arguments. Usually we wouldn't do this anyway because llvm_fenv_testexcept would return an exception, but we have seen some cases where neither errno nor fenv detect an exception on arm-linux. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114893 91177308-0d34-0410-b5e6-96231b3b80d8		2010-09-27 21:29:20 +00:00
..
IPA	Remove the experimental AliasAnalysis::getDependency interface, which	2010-09-14 21:25:10 +00:00
AliasAnalysis.cpp	Remove the experimental AliasAnalysis::getDependency interface, which	2010-09-14 21:25:10 +00:00
AliasAnalysisCounter.cpp	Remove the experimental AliasAnalysis::getDependency interface, which	2010-09-14 21:25:10 +00:00
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp	Remove the experimental AliasAnalysis::getDependency interface, which	2010-09-14 21:25:10 +00:00
AliasSetTracker.cpp
Analysis.cpp
BasicAliasAnalysis.cpp	PR7959: Handle negative scales in GEPs correctly in BasicAA for non-64-bit	2010-09-15 20:08:03 +00:00
CaptureTracking.cpp
CFGPrinter.cpp
CMakeLists.txt	Update CMake build.	2010-09-16 23:06:18 +00:00
ConstantFolding.cpp	Don't try to constant fold libm functions with non-finite arguments.	2010-09-27 21:29:20 +00:00
DbgInfoPrinter.cpp
DebugInfo.cpp	Simplify code.	2010-09-21 16:41:29 +00:00
DomPrinter.cpp
InlineCost.cpp
InstCount.cpp
InstructionSimplify.cpp	Revert r114097, adding back in the assertion against replacing an Instruction by itself. Now that CorrelatedValuePropagation is	2010-09-16 20:51:41 +00:00
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp
LazyValueInfo.cpp	It is possible, under specific circumstances involving ptrtoint ConstantExpr's, for LVI to end up trying to merge	2010-09-16 18:28:33 +00:00
LibCallAliasAnalysis.cpp	Remove the experimental AliasAnalysis::getDependency interface, which	2010-09-14 21:25:10 +00:00
LibCallSemantics.cpp
Lint.cpp
LiveValues.cpp
Loads.cpp
LoopDependenceAnalysis.cpp
LoopInfo.cpp
LoopPass.cpp
Makefile
MemDepPrinter.cpp	Add an #include of raw_ostream.h. Previously, this only compiled	2010-09-17 00:33:43 +00:00
MemoryBuiltins.cpp
MemoryDependenceAnalysis.cpp	Teach memdep about TBAA tags.	2010-09-22 21:41:02 +00:00
ModuleDebugInfoPrinter.cpp
PHITransAddr.cpp
PointerTracking.cpp
PostDominators.cpp
ProfileEstimatorPass.cpp
ProfileInfo.cpp
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp
ProfileVerifierPass.cpp
README.txt
RegionInfo.cpp
RegionPrinter.cpp
ScalarEvolution.cpp
ScalarEvolutionAliasAnalysis.cpp	Remove the experimental AliasAnalysis::getDependency interface, which	2010-09-14 21:25:10 +00:00
ScalarEvolutionExpander.cpp
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp
Trace.cpp
TypeBasedAliasAnalysis.cpp	Convert TBAA to use the new TBAATag field of AliasAnalysis::Location.	2010-09-14 23:28:12 +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))

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