llvm-6502/lib/Analysis
Andrew Trick d9fc1ce809 Fix 12513: Loop unrolling breaks with indirect branches.
Take this opportunity to generalize the indirectbr bailout logic for
loop transformations. CFG transformations will never get indirectbr
right, and there's no point trying.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154386 91177308-0d34-0410-b5e6-96231b3b80d8
2012-04-10 05:14:42 +00:00
..
IPA Handle intrinsics in GlobalsModRef. Fixes pr12351. 2012-03-28 21:31:24 +00:00
AliasAnalysis.cpp Move isKnownNonNull from private implementation detail of BasicAA to a public 2012-02-25 10:56:28 +00:00
AliasAnalysisCounter.cpp Persuade GCC that there is nothing worth warning about here (there isn't). 2012-02-05 14:20:11 +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 Have AliasSet::aliasesUnknownInst use pointer TBAA info when available 2012-02-10 15:52:39 +00:00
Analysis.cpp
BasicAliasAnalysis.cpp Duncan pointed out that if the alignment isn't explicitly specified, it defaults to the ABI alignment. Given that, make this code a bit more aggressive in such cases. 2012-02-27 23:16:46 +00:00
BlockFrequencyInfo.cpp Add some constantness to BranchProbabilityInfo and BlockFrequnencyInfo. 2011-12-20 20:03:10 +00:00
BranchProbabilityInfo.cpp Make the unreachable probability much much heavier. The previous 2011-12-22 09:26:37 +00:00
CaptureTracking.cpp Move includes to the .cpp file. 2012-01-17 22:16:31 +00:00
CFGPrinter.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
CMakeLists.txt Pull the implementation of the code metrics out of the inline cost 2012-03-16 05:51:52 +00:00
CodeMetrics.cpp Initial commit for the rewrite of the inline cost analysis to operate 2012-03-31 12:42:41 +00:00
ConstantFolding.cpp Convert assert(0) to llvm_unreachable 2012-02-07 05:05:23 +00:00
DbgInfoPrinter.cpp
DebugInfo.cpp Add a line number for the scope of the function (starting at the first 2012-04-03 00:43:49 +00:00
DIBuilder.cpp Add a line number for the scope of the function (starting at the first 2012-04-03 00:43:49 +00:00
DominanceFrontier.cpp Unweaken vtables as per http://llvm.org/docs/CodingStandards.html#ll_virtual_anch 2011-12-20 02:50:00 +00:00
DomPrinter.cpp remove the blank line from previous ci. 2012-02-04 03:18:47 +00:00
InlineCost.cpp Reintroduce InlineCostAnalyzer::getInlineCost() variant with explicit callee 2012-04-06 17:27:41 +00:00
InstCount.cpp
InstructionSimplify.cpp Revert r153521 as it's causing large regressions on the nightly testers. 2012-03-28 18:42:50 +00:00
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp Cleanup IVUsers::addUsersIfInteresting. 2012-03-22 17:47:33 +00:00
LazyValueInfo.cpp llvm::SwitchInst 2012-03-11 06:09:17 +00:00
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp Always compute all the bits in ComputeMaskedBits. 2012-04-04 12:51:34 +00:00
LLVMBuild.txt LLVMBuild: Introduce a common section which currently has a list of the 2011-12-12 22:45:54 +00:00
Loads.cpp enhance jump threading to preserve TBAA information when PRE'ing loads, 2012-03-13 18:07:41 +00:00
LoopDependenceAnalysis.cpp More dead code removal (using -Wunreachable-code) 2012-01-20 21:51:11 +00:00
LoopInfo.cpp Fix 12513: Loop unrolling breaks with indirect branches. 2012-04-10 05:14:42 +00:00
LoopPass.cpp Take out the debug info probe stuff. It's making some changes to 2012-03-23 03:54:05 +00:00
Makefile
MemDepPrinter.cpp Fix a stupid typo in MemDepPrinter. 2011-12-14 02:54:39 +00:00
MemoryBuiltins.cpp Validate the return type when checking if a function is malloc. 2011-11-23 17:58:47 +00:00
MemoryDependenceAnalysis.cpp Don't call dominates on unreachable instructions. Should fix the dragonegg 2012-02-26 05:30:08 +00:00
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp
PathNumbering.cpp [unwind removal] We no longer have 'unwind' instructions being generated, so 2012-02-06 21:16:41 +00:00
PathProfileInfo.cpp
PathProfileVerifier.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
PHITransAddr.cpp Uniformize the InstructionSimplify interface by ensuring that all routines 2012-03-13 11:42:19 +00:00
PostDominators.cpp
ProfileEstimatorPass.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
ProfileInfo.cpp
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
ProfileVerifierPass.cpp Move code into anonymous namespaces. 2011-11-26 23:01:57 +00:00
README.txt
RegionInfo.cpp Remove extra semi-colons. 2012-02-22 17:25:00 +00:00
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp SCEV: When expanding a GEP the final addition to the base pointer has NUW but not NSW. 2012-04-07 17:19:26 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp Fix this assert. IP can point to an instruction with strange dominance 2012-02-27 02:13:03 +00:00
ScalarEvolutionNormalization.cpp More dead code removal (using -Wunreachable-code) 2012-01-20 21:51:11 +00:00
SparsePropagation.cpp Taken into account Duncan's comments for r149481 dated by 2nd Feb 2012: 2012-03-08 07:06:20 +00:00
Trace.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
TypeBasedAliasAnalysis.cpp
ValueTracking.cpp Fix ValueTracking to conclude that debug intrinsics are safe to 2012-04-07 19:22:18 +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))

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