llvm-6502/lib/Analysis
Duncan Sands 1f6a329f79 Silence a bunch (but not all) "variable written but not read" warnings
when building with assertions disabled.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137460 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-12 14:54:45 +00:00
..
IPA Silence a bunch (but not all) "variable written but not read" warnings 2011-08-12 14:54:45 +00:00
AliasAnalysis.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
AliasDebugger.cpp
AliasSetTracker.cpp Minor simplification. 2011-07-27 01:02:25 +00:00
Analysis.cpp Rename BlockFrequency to BlockFrequencyInfo and MachineBlockFrequency to 2011-07-25 19:25:40 +00:00
BasicAliasAnalysis.cpp Explicitly cast narrowing conversions inside {}s that will become errors in 2011-07-27 06:22:51 +00:00
BlockFrequencyInfo.cpp Add more constantness in BlockFrequencyInfo. 2011-08-03 21:30:57 +00:00
BranchProbabilityInfo.cpp Change SmallVector to SmallPtrSet in BranchProbabilityInfo. Handle cases where 2011-08-01 19:16:26 +00:00
CaptureTracking.cpp
CFGPrinter.cpp
CMakeLists.txt Rewrite the CMake build to use explicit dependencies between libraries, 2011-07-29 00:14:25 +00:00
ConstantFolding.cpp Convert GetElementPtrInst to use ArrayRef. 2011-07-25 09:48:08 +00:00
DbgInfoPrinter.cpp
DebugInfo.cpp Distinguish between two copies of one inlined variable. Take 2. 2011-08-10 21:50:54 +00:00
DIBuilder.cpp Reapply r135457. This needs llvm-gcc change, that I forgot to check-in yesterday. 2011-07-19 19:41:54 +00:00
DominanceFrontier.cpp
DomPrinter.cpp
InlineCost.cpp
InstCount.cpp
InstructionSimplify.cpp Fix what seems an obvious typo. Patch by Ivan Krasin. Problem 2011-08-04 10:02:21 +00:00
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp Teach IVUsers to stop at non-affine expressions unless they are both 2011-07-01 22:05:19 +00:00
LazyValueInfo.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
Loads.cpp Convert TargetData::getIndexedOffset to use ArrayRef. 2011-07-19 14:01:37 +00:00
LoopDependenceAnalysis.cpp
LoopInfo.cpp Silence a bunch (but not all) "variable written but not read" warnings 2011-08-12 14:54:45 +00:00
LoopPass.cpp Reapplying r136844. 2011-08-10 23:22:57 +00:00
Makefile
MemDepPrinter.cpp Add "unknown" results for memdep, which mean "I don't know whether a dependence for the given instruction exists in the given block". This cleans up all the existing hacks in memdep which represent this concept by returning clobber with various unrelated instructions. 2011-06-15 00:47:34 +00:00
MemoryBuiltins.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
MemoryDependenceAnalysis.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp
PathNumbering.cpp Add this back in for now. There are still a few passes which create unwind instructions at the moment. 2011-08-03 01:07:57 +00:00
PathProfileInfo.cpp
PathProfileVerifier.cpp
PHITransAddr.cpp Shorten some expressions by using ArrayRef::slice(). 2011-07-25 15:13:01 +00:00
PostDominators.cpp
ProfileEstimatorPass.cpp
ProfileInfo.cpp
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp
ProfileVerifierPass.cpp
README.txt
RegionInfo.cpp
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp Allow loop unrolling to get known trip counts from ScalarEvolution. 2011-08-11 23:36:16 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp Convert IRBuilder::CreateGEP and IRBuilder::CreateInBoundsGEP to use 2011-07-22 08:16:57 +00:00
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp
Trace.cpp
TypeBasedAliasAnalysis.cpp
ValueTracking.cpp Migrate LLVM and Clang to use the new makeArrayRef(...) functions where previously explicit non-default constructors were used. 2011-07-18 12:00:32 +00:00

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))

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