llvm-6502/lib/Analysis
Chris Lattner 0ee443d169 The phi translated pointer can be computed when returning a partially cached result
instead of stored.  This reduces memdep memory usage, and also eliminates a bunch of
weakvh's.  This speeds up gvn on gcc.c-torture/20001226-1.c from 23.9s to 8.45s (2.8x)
on a different machine than earlier.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91885 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-22 04:25:02 +00:00
..
IPA Remove isPod() from DenseMapInfo, splitting it out to its own 2009-12-15 07:26:43 +00:00
AliasAnalysis.cpp
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp
AliasSetTracker.cpp
Analysis.cpp
BasicAliasAnalysis.cpp
CaptureTracking.cpp Reuse the Threshold value to size these containers because it's 2009-12-09 18:48:53 +00:00
CFGPrinter.cpp
CMakeLists.txt
ConstantFolding.cpp
DbgInfoPrinter.cpp Fix GetConstantStringInfo to not look into MDString (it works on 2009-12-15 19:34:20 +00:00
DebugInfo.cpp Add support to emit debug info for C++ namespaces. 2009-12-15 19:16:48 +00:00
DomPrinter.cpp
InlineCost.cpp
InstCount.cpp
InstructionSimplify.cpp
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp Add Loop contains utility methods for testing whether a loop 2009-12-18 01:24:09 +00:00
LazyValueInfo.cpp
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
LiveValues.cpp
LoopDependenceAnalysis.cpp
LoopInfo.cpp Add Loop contains utility methods for testing whether a loop 2009-12-18 01:24:09 +00:00
LoopPass.cpp
Makefile
MemoryBuiltins.cpp
MemoryDependenceAnalysis.cpp The phi translated pointer can be computed when returning a partially cached result 2009-12-22 04:25:02 +00:00
PHITransAddr.cpp
PointerTracking.cpp
PostDominators.cpp
ProfileEstimatorPass.cpp
ProfileInfo.cpp You can't use typedefs to declare template member specializations, and 2009-12-15 02:35:24 +00:00
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp
ProfileVerifierPass.cpp
README.txt
ScalarEvolution.cpp Fix a spello in a comment that Nick spotted. 2009-12-19 01:46:34 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp
SparsePropagation.cpp Eliminate unnecessary LLVMContexts. 2009-12-18 23:42:08 +00:00
Trace.cpp
ValueTracking.cpp Fix GetConstantStringInfo to not look into MDString (it works on 2009-12-15 19:34:20 +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.

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