llvm-6502/lib/Analysis
Chandler Carruth 54fec07ec0 [PM] Split the CallGraph out from the ModulePass which creates the
CallGraph.

This makes the CallGraph a totally generic analysis object that is the
container for the graph data structure and the primary interface for
querying and manipulating it. The pass logic is separated into its own
class. For compatibility reasons, the pass provides wrapper methods for
most of the methods on CallGraph -- they all just forward.

This will allow the new pass manager infrastructure to provide its own
analysis pass that constructs the same CallGraph object and makes it
available. The idea is that in the new pass manager, the analysis pass's
'run' method returns a concrete analysis 'result'. Here, that result is
a 'CallGraph'. The 'run' method will typically do only minimal work,
deferring much of the work into the implementation of the result object
in order to be lazy about computing things, but when (like DomTree)
there is *some* up-front computation, the analysis does it prior to
handing the result back to the querying pass.

I know some of this is fairly ugly. I'm happy to change it around if
folks can suggest a cleaner interim state, but there is going to be some
amount of unavoidable ugliness during the transition period. The good
thing is that this is very limited and will naturally go away when the
old pass infrastructure goes away. It won't hang around to bother us
later.

Next up is the initial new-PM-style call graph analysis. =]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195722 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-26 04:19:30 +00:00
..
IPA [PM] Split the CallGraph out from the ModulePass which creates the 2013-11-26 04:19:30 +00:00
AliasAnalysis.cpp
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp
AliasSetTracker.cpp
Analysis.cpp delinearization of arrays 2013-11-12 22:47:20 +00:00
BasicAliasAnalysis.cpp Use correct size for address space in BasicAA. 2013-11-16 00:36:43 +00:00
BlockFrequencyInfo.cpp Added BlockFrequencyInfo::view for displaying the block frequency propagation graph via graphviz. 2013-11-14 02:27:46 +00:00
BranchProbabilityInfo.cpp Consider (x == -1) unlikely in BranchProbabilityInfo 2013-11-01 10:58:22 +00:00
CaptureTracking.cpp
CFG.cpp
CFGPrinter.cpp
CMakeLists.txt delinearization of arrays 2013-11-12 22:47:20 +00:00
CodeMetrics.cpp
ConstantFolding.cpp Add addrspacecast instruction. 2013-11-15 01:34:59 +00:00
CostModel.cpp
Delinearization.cpp add more comments around the delinearization of arrays 2013-11-13 22:37:58 +00:00
DependenceAnalysis.cpp add more comments around the delinearization of arrays 2013-11-13 22:37:58 +00:00
DominanceFrontier.cpp
DomPrinter.cpp
InstCount.cpp
InstructionSimplify.cpp
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp
LazyValueInfo.cpp
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp Use size function instead of manually calculating it. 2013-11-10 03:18:50 +00:00
LLVMBuild.txt
Loads.cpp
LoopInfo.cpp Simplify code. No functionality change. 2013-11-13 20:18:38 +00:00
LoopPass.cpp
Makefile
MemDepPrinter.cpp
MemoryBuiltins.cpp fix PR17635: false positive with packed structures 2013-10-24 09:17:24 +00:00
MemoryDependenceAnalysis.cpp Fixing a heisenbug where the memory dependence analysis behaves differently 2013-11-14 01:10:52 +00:00
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp
PHITransAddr.cpp
PostDominators.cpp
PtrUseVisitor.cpp
README.txt
RegionInfo.cpp
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp Annotate APInt methods where it's not clear whether they are in place with warn_unused_result. 2013-11-16 16:25:41 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp Fix SCEVExpander: don't try to expand quadratic recurrences outside a loop. 2013-10-25 21:35:56 +00:00
ScalarEvolutionNormalization.cpp Fix LSR: don't normalize quadratic recurrences. 2013-10-25 21:35:52 +00:00
SparsePropagation.cpp
TargetTransformInfo.cpp
Trace.cpp
TypeBasedAliasAnalysis.cpp TBAA: fix PR17620. 2013-10-22 01:40:25 +00:00
ValueTracking.cpp Don't speculate loads under ThreadSanitizer 2013-11-21 07:29:28 +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))

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