llvm-6502/lib/Analysis
Paul Redmond ee21b6f7b4 Add support for llvm.vectorizer metadata
- llvm.loop.parallel metadata has been renamed to llvm.loop to be more generic
  by making the root of additional loop metadata.
  - Loop::isAnnotatedParallel now looks for llvm.loop and associated
    llvm.mem.parallel_loop_access
  - document llvm.loop and update llvm.mem.parallel_loop_access
- add support for llvm.vectorizer.width and llvm.vectorizer.unroll
  - document llvm.vectorizer.* metadata
  - add utility class LoopVectorizerHints for getting/setting loop metadata
  - use llvm.vectorizer.width=1 to indicate already vectorized instead of
    already_vectorized
- update existing tests that used llvm.loop.parallel and
  llvm.vectorizer.already_vectorized

Reviewed by: Nadav Rotem


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182802 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-28 20:00:34 +00:00
..
IPA This patch breaks up Wrap.h so that it does not have to include all of 2013-05-01 20:59:00 +00:00
AliasAnalysis.cpp Make BasicAliasAnalysis recognize the fact a noalias argument cannot alias another argument, even if the other argument is not itself marked noalias. 2013-05-28 08:17:48 +00:00
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp
AliasSetTracker.cpp
Analysis.cpp This patch breaks up Wrap.h so that it does not have to include all of 2013-05-01 20:59:00 +00:00
BasicAliasAnalysis.cpp Make BasicAliasAnalysis recognize the fact a noalias argument cannot alias another argument, even if the other argument is not itself marked noalias. 2013-05-28 08:17:48 +00:00
BlockFrequencyInfo.cpp
BranchProbabilityInfo.cpp Do not reserve space for the ColdEdges and NormalEdges vectors. 2013-05-24 17:00:22 +00:00
CaptureTracking.cpp
CFGPrinter.cpp
CMakeLists.txt
CodeMetrics.cpp
ConstantFolding.cpp ConstantFolding: ComputeMaskedBits wants the scalar size for vectors. 2013-04-19 16:56:24 +00:00
CostModel.cpp CostModel: Add parameter to instruction cost to further classify operand values 2013-04-04 23:26:21 +00:00
DependenceAnalysis.cpp
DominanceFrontier.cpp
DomPrinter.cpp
InstCount.cpp
InstructionSimplify.cpp InstructionSimplify.cpp: Fix a ligature, "fi", to get rid of utf8 in comment. 2013-04-08 23:05:21 +00:00
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp
LazyValueInfo.cpp
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp
LLVMBuild.txt
Loads.cpp
LoopInfo.cpp Add support for llvm.vectorizer metadata 2013-05-28 20:00:34 +00:00
LoopPass.cpp
Makefile
MemDepPrinter.cpp
MemoryBuiltins.cpp Respect the 'nobuiltin' attribute when determining if a call is to a memory builtin. 2013-05-16 04:12:04 +00:00
MemoryDependenceAnalysis.cpp Use only explicit bool conversion operators 2013-05-15 07:36:59 +00:00
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp
PathNumbering.cpp
PathProfileInfo.cpp
PathProfileVerifier.cpp Build fixes for STLPort + GCC 2013-03-29 18:48:45 +00:00
PHITransAddr.cpp
PostDominators.cpp
ProfileDataLoader.cpp
ProfileDataLoaderPass.cpp
ProfileEstimatorPass.cpp
ProfileInfo.cpp Build fixes for STLPort + GCC 2013-03-29 18:48:45 +00:00
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp
ProfileVerifierPass.cpp
PtrUseVisitor.cpp
README.txt
RegionInfo.cpp RegionInfo: Do not crash if unreachable block is found 2013-05-03 15:48:34 +00:00
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp
TargetTransformInfo.cpp CostModel: Add parameter to instruction cost to further classify operand values 2013-04-04 23:26:21 +00:00
Trace.cpp
TypeBasedAliasAnalysis.cpp Struct-path aware TBAA: change the format of TBAAStructType node. 2013-04-27 00:26:11 +00:00
ValueTracking.cpp Replace Count{Leading,Trailing}Zeros_{32,64} with count{Leading,Trailing}Zeros. 2013-05-24 22:23:49 +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))

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