llvm-6502/lib/Analysis
Devang Patel c5ecbdc189 Preserve debug loc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134441 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-05 21:48:22 +00:00
..
IPA Teach the CallGraph to ignore calls to intrinsics. 2011-06-09 19:46:27 +00:00
AliasAnalysis.cpp When analyzing functions known to only access argument pointees, 2011-04-27 18:39:03 +00:00
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp
AliasSetTracker.cpp
Analysis.cpp Introduce BlockFrequency analysis for BasicBlocks. 2011-06-23 21:45:20 +00:00
BasicAliasAnalysis.cpp Initialize BasicAA's AliasCache to set it to use fewer buckets by 2011-06-10 22:30:30 +00:00
BlockFrequency.cpp Missing files for the BlockFrequency analysis added. 2011-06-23 21:56:59 +00:00
BranchProbabilityInfo.cpp Calculate backedge probability correctly. 2011-06-23 23:52:11 +00:00
CaptureTracking.cpp
CFGPrinter.cpp
CMakeLists.txt Introduce BlockFrequency analysis for BasicBlocks. 2011-06-23 21:45:20 +00:00
ConstantFolding.cpp Revert "revert 133714" 2011-06-23 14:19:39 +00:00
DbgInfoPrinter.cpp
DebugInfo.cpp Simplify code. No functionality change. 2011-06-18 14:42:42 +00:00
DIBuilder.cpp Fix struct member's scope. Patch by Xi Wang. 2011-06-24 22:00:39 +00:00
DominanceFrontier.cpp
DomPrinter.cpp
InlineCost.cpp Change condition for determining whether a function is small for inlining metrics so that very long functions 2011-05-24 20:22:24 +00:00
InstCount.cpp
InstructionSimplify.cpp Improve constant folding of undef for cmp and select operators. 2011-07-01 01:03:43 +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 llvm.memcpy.* has two distinct associated address spaces; the source address space, and the destination address space. Fix up the interface on MemIntrinsic and MemTransferInst to make this clear, and fix InstructionDereferencesPointer in LazyValueInfo.cpp to use the interface properly. 2011-05-31 20:40:16 +00:00
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp
Loads.cpp Test commit. 2011-06-03 17:15:37 +00:00
LoopDependenceAnalysis.cpp
LoopInfo.cpp
LoopPass.cpp
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 simplify some code. 2011-06-18 21:46:23 +00:00
MemoryDependenceAnalysis.cpp Add a limit to the number of instructions memdep will scan in a single block. This prevents (at least in some cases) O(N^2) runtime in passes like DSE. 2011-06-15 23:59:25 +00:00
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp
PathNumbering.cpp Remove unused STL header includes. 2011-04-23 19:53:52 +00:00
PathProfileInfo.cpp
PathProfileVerifier.cpp Fix a ton of comment typos found by codespell. Patch by 2011-04-15 05:18:47 +00:00
PHITransAddr.cpp
PostDominators.cpp
ProfileEstimatorPass.cpp Fix a ton of comment typos found by codespell. Patch by 2011-04-15 05:18:47 +00:00
ProfileInfo.cpp Fix a ton of comment typos found by codespell. Patch by 2011-04-15 05:18:47 +00:00
ProfileInfoLoader.cpp Remove unused STL header includes. 2011-04-23 19:53:52 +00:00
ProfileInfoLoaderPass.cpp
ProfileVerifierPass.cpp
README.txt
RegionInfo.cpp
RegionPass.cpp Minor change: Fix the typo in RegionPass.h and RegionPass.cpp. 2011-05-05 13:59:38 +00:00
RegionPrinter.cpp
ScalarEvolution.cpp SCEV: missing null check fix for r132360, dragonegg crash. 2011-06-01 19:14:56 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp Preserve debug loc. 2011-07-05 21:48:22 +00:00
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp
Trace.cpp
TypeBasedAliasAnalysis.cpp Fix a ton of comment typos found by codespell. Patch by 2011-04-15 05:18:47 +00:00
ValueTracking.cpp Move onlyUsedByLifetimeMarkers to ValueTracking so that it can be used by other 2011-06-27 04:20:45 +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))

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