llvm-project/llvm/lib/Analysis
James Molloy 87405c7f66 Separate out BDCE's analysis into a separate DemandedBits analysis.
This allows other areas of the compiler to use BDCE's bit-tracking.
NFCI.

llvm-svn: 245039
2015-08-14 11:09:09 +00:00
..
IPA [PM/AA] Extract the interface for GlobalsModRef into a header along with 2015-08-14 03:48:20 +00:00
AliasAnalysis.cpp [PM/AA] Simplify the AliasAnalysis interface by removing a wrapper 2015-08-06 02:05:46 +00:00
AliasAnalysisCounter.cpp [PM/AA] Sink all the actual code from AliasAnalysisCounter back into the 2015-08-14 02:12:12 +00:00
AliasAnalysisEvaluator.cpp [PM/AA] Simplify the AliasAnalysis interface by removing a wrapper 2015-08-06 02:05:46 +00:00
AliasSetTracker.cpp [PM/AA] Simplify the AliasAnalysis interface by removing a wrapper 2015-08-06 02:05:46 +00:00
Analysis.cpp Separate out BDCE's analysis into a separate DemandedBits analysis. 2015-08-14 11:09:09 +00:00
AssumptionCache.cpp [PM] Actually add the new pass manager support for the assumption cache. 2015-01-22 21:53:09 +00:00
BasicAliasAnalysis.cpp [PM/AA] Clean up and homogenize comments throughout basic-aa. 2015-08-06 08:17:06 +00:00
BlockFrequencyInfo.cpp Add new constructors for LoopInfo/DominatorTree/BFI/BPI 2015-07-16 23:23:35 +00:00
BlockFrequencyInfoImpl.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
BranchProbabilityInfo.cpp Create a wrapper pass for BranchProbabilityInfo. 2015-07-15 22:48:29 +00:00
CFG.cpp [CaptureTracking] Avoid long compilation time on large basic blocks 2015-06-24 17:53:17 +00:00
CFGPrinter.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
CFLAliasAnalysis.cpp [PM/AA] Hoist the value handle definition for CFLAA into the header to 2015-08-14 02:50:34 +00:00
CGSCCPassManager.cpp [PM] Remove the defunt CGSCC-specific debug flag. 2015-01-13 22:45:13 +00:00
CMakeLists.txt Separate out BDCE's analysis into a separate DemandedBits analysis. 2015-08-14 11:09:09 +00:00
CaptureTracking.cpp [CaptureTracker] Provide an ordered basic block to PointerMayBeCapturedBefore 2015-07-31 14:31:35 +00:00
CodeMetrics.cpp [IR] Add token types 2015-08-14 05:09:07 +00:00
ConstantFolding.cpp Fix assert when inlining a constantexpr addrspacecast 2015-07-27 18:31:03 +00:00
CostModel.cpp Roll forward r243250 2015-07-26 19:10:03 +00:00
Delinearization.cpp Move delinearization from SCEVAddRecExpr to ScalarEvolution 2015-06-29 14:42:48 +00:00
DemandedBits.cpp Separate out BDCE's analysis into a separate DemandedBits analysis. 2015-08-14 11:09:09 +00:00
DependenceAnalysis.cpp [PM/AA] Simplify the AliasAnalysis interface by removing a wrapper 2015-08-06 02:05:46 +00:00
DivergenceAnalysis.cpp Rename inst_range() to instructions() for consistency. NFC 2015-08-06 19:10:45 +00:00
DomPrinter.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
DominanceFrontier.cpp Templatify DominanceFrontier. 2014-07-12 21:59:52 +00:00
IVUsers.cpp [LSR] don't attempt to promote ephemeral values to indvars 2015-07-13 03:28:53 +00:00
InstCount.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
InstructionSimplify.cpp [InstSimplify] Teach InstSimplify how to simplify extractelement 2015-07-13 01:15:53 +00:00
Interval.cpp Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges." 2014-07-21 17:06:51 +00:00
IntervalPartition.cpp [C++11] More 'nullptr' conversion. In some cases just using a boolean check instead of comparing to nullptr. 2014-04-15 04:59:12 +00:00
IteratedDominanceFrontier.cpp Move IDF Calculation to a separate file, expose an interface to it. 2015-04-21 19:13:02 +00:00
LLVMBuild.txt Update libdeps since TLI was moved from Target to Analysis in r226078. 2015-01-15 05:21:00 +00:00
LazyCallGraph.cpp Revert r225854: [PM] Move the LazyCallGraph printing functionality to 2015-01-14 00:27:45 +00:00
LazyValueInfo.cpp -Wdeprecated-clean: Fix cases of violating the rule of 5 in ways that are deprecated in C++11 2015-08-03 22:30:24 +00:00
LibCallAliasAnalysis.cpp [PM/AA] Remove the function names and class names from doxygen comments 2015-08-14 01:43:46 +00:00
LibCallSemantics.cpp Move the personality function from LandingPadInst to Function 2015-06-17 20:52:32 +00:00
Lint.cpp [PM/AA] Simplify the AliasAnalysis interface by removing a wrapper 2015-08-06 02:05:46 +00:00
Loads.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
LoopAccessAnalysis.cpp [LAA] Change name from addRuntimeCheck to addRuntimeChecks, NFC 2015-08-11 00:09:37 +00:00
LoopInfo.cpp [IR] Add token types 2015-08-14 05:09:07 +00:00
LoopPass.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
Makefile
MemDepPrinter.cpp Rename inst_range() to instructions() for consistency. NFC 2015-08-06 19:10:45 +00:00
MemDerefPrinter.cpp Rename inst_range() to instructions() for consistency. NFC 2015-08-06 19:10:45 +00:00
MemoryBuiltins.cpp DataLayout is mandatory, update the API to reflect it with references. 2015-03-10 02:37:25 +00:00
MemoryDependenceAnalysis.cpp [PM/AA] Add missing static dependency edges from DSE and memdep to TLI. 2015-08-12 18:10:45 +00:00
MemoryLocation.cpp [PM/AA] Split the location computation out of getArgLocation so the 2015-06-17 07:12:40 +00:00
ModuleDebugInfoPrinter.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
NoAliasAnalysis.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
OrderedBasicBlock.cpp [CaptureTracker] Provide an ordered basic block to PointerMayBeCapturedBefore 2015-07-31 14:31:35 +00:00
PHITransAddr.cpp [PHITransAddr] Don't assume that instruction operands are translatable 2015-08-09 15:43:02 +00:00
PostDominators.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
PtrUseVisitor.cpp Update SetVector to rely on the underlying set's insert to return a pair<iterator, bool> 2014-11-19 07:49:26 +00:00
README.txt
RegionInfo.cpp [RegionInfo] Add debug-time region viewer functions 2015-08-10 13:21:59 +00:00
RegionPass.cpp Change range-based for-loops to be -Wrange-loop-analysis clean. 2015-04-15 01:21:15 +00:00
RegionPrinter.cpp [RegionInfo] Add debug-time region viewer functions 2015-08-10 13:21:59 +00:00
ScalarEvolution.cpp [IndVars] Fix PR24356. 2015-08-06 20:43:41 +00:00
ScalarEvolutionAliasAnalysis.cpp [PM/AA] Clean up the SCEV-AA comment formatting and typos. 2015-08-14 03:14:50 +00:00
ScalarEvolutionExpander.cpp [IndVarSimplify] Make cost estimation in RewriteLoopExitValues smarter 2015-08-10 18:23:58 +00:00
ScalarEvolutionNormalization.cpp Fix typos in comments, NFC 2014-08-29 21:53:01 +00:00
ScopedNoAliasAA.cpp [PM/AA] Hoist ScopedNoAliasAA's interface into a header and move the 2015-08-14 02:55:50 +00:00
SparsePropagation.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
StratifiedSets.h Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
TargetLibraryInfo.cpp Populate list of vectorizable functions for Accelerate library. 2015-05-07 17:11:51 +00:00
TargetTransformInfo.cpp [TTI] Add a hook for specifying per-target defaults for Interleaved Accesses 2015-08-10 14:50:54 +00:00
Trace.cpp
TypeBasedAliasAnalysis.cpp [PM/AA] Hoist the interface to TBAA into a dedicated header along with 2015-08-14 03:33:48 +00:00
ValueTracking.cpp [ValueTracking] Tweak a comment slightly 2015-08-12 15:11:43 +00:00
VectorUtils.cpp De-constify pointers to Type since they can't be modified. NFC 2015-08-01 22:20:21 +00:00

README.txt

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))

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