llvm-6502/lib/Analysis
Tobias Grosser 5e66eea5ba ScalarEvolution: Derive element size from the type of the loaded element
Before, we where looking at the size of the pointer type that specifies the
location from which to load the element. This did not make any sense at all.

This change fixes a bug in the delinearization where we failed to delinerize
certain load instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@210435 91177308-0d34-0410-b5e6-96231b3b80d8
2014-06-08 19:21:20 +00:00
..
IPA Check the alwaysinline attribute on the call as well as on the caller. 2014-05-19 18:25:54 +00:00
AliasAnalysis.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
AliasAnalysisCounter.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
AliasAnalysisEvaluator.cpp [C++11] Add 'override' keyword to virtual methods that override their base class. 2014-03-05 07:30:04 +00:00
AliasDebugger.cpp [C++11] Add 'override' keyword to virtual methods that override their base class. 2014-03-05 07:30:04 +00:00
AliasSetTracker.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
Analysis.cpp Add a new attribute called 'jumptable' that creates jump-instruction tables for functions marked with this attribute. 2014-06-05 19:29:43 +00:00
BasicAliasAnalysis.cpp Remove a couple of redundant copies of SmallVector::operator==. 2014-04-18 19:48:03 +00:00
BlockFrequencyInfo.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
BlockFrequencyInfoImpl.cpp blockfreq: Move include to .cpp 2014-05-06 01:57:42 +00:00
BranchProbabilityInfo.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
CaptureTracking.cpp [C++11] Add range based accessors for the Use-Def chain of a Value. 2014-03-09 03:16:01 +00:00
CFG.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
CFGPrinter.cpp Clean up language and grammar. 2014-05-20 17:11:11 +00:00
CGSCCPassManager.cpp [PM] Add a new-PM-style CGSCC pass manager using the newly added 2014-04-21 11:12:00 +00:00
CMakeLists.txt Add a new attribute called 'jumptable' that creates jump-instruction tables for functions marked with this attribute. 2014-06-05 19:29:43 +00:00
CodeMetrics.cpp Consistent use of the noduplicate attribute. 2014-03-17 16:19:07 +00:00
ConstantFolding.cpp Add a Constant version of stripPointerCasts. 2014-06-04 19:01:48 +00:00
CostModel.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
Delinearization.cpp remove BasePointer before delinearizing 2014-05-27 22:41:51 +00:00
DependenceAnalysis.cpp remove BasePointer before delinearizing 2014-05-27 22:41:51 +00:00
DominanceFrontier.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
DomPrinter.cpp [PM] Split DominatorTree into a concrete analysis result object which 2014-01-13 13:07:17 +00:00
InstCount.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
InstructionSimplify.cpp InstSimplify: Improve handling of ashr/lshr 2014-05-16 17:14:03 +00:00
Interval.cpp [Modules] Move CFG.h to the IR library as it defines graph traits over 2014-03-04 11:45:46 +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
IVUsers.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
JumpInstrTableInfo.cpp Add a new attribute called 'jumptable' that creates jump-instruction tables for functions marked with this attribute. 2014-06-05 19:29:43 +00:00
LazyCallGraph.cpp Fix typos 2014-05-15 01:52:21 +00:00
LazyValueInfo.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
LibCallAliasAnalysis.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
LibCallSemantics.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
Lint.cpp Rename ComputeMaskedBits to computeKnownBits. "Masked" has been 2014-05-14 21:14:37 +00:00
LLVMBuild.txt LLVMBuild: Introduce a common section which currently has a list of the 2011-12-12 22:45:54 +00:00
Loads.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
LoopInfo.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
LoopPass.cpp Add C API for thread yielding callback. 2014-05-16 02:33:15 +00:00
Makefile
MemDepPrinter.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
MemoryBuiltins.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
MemoryDependenceAnalysis.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
ModuleDebugInfoPrinter.cpp [C++11] Change DebugInfoFinder to use range-based loops 2014-03-18 09:41:07 +00:00
NoAliasAnalysis.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
PHITransAddr.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
PostDominators.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
PtrUseVisitor.cpp [C++11] Add range based accessors for the Use-Def chain of a Value. 2014-03-09 03:16:01 +00:00
README.txt
RegionInfo.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
RegionPass.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
RegionPrinter.cpp Use unique_ptr to manage ownership of child Regions within llvm::Region 2014-04-15 18:32:43 +00:00
ScalarEvolution.cpp ScalarEvolution: Derive element size from the type of the loaded element 2014-06-08 19:21:20 +00:00
ScalarEvolutionAliasAnalysis.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
ScalarEvolutionExpander.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
ScalarEvolutionNormalization.cpp test check-in: added missing parenthesis in comment 2014-05-28 19:03:33 +00:00
SparsePropagation.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
TargetTransformInfo.cpp [Modules] Fix potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:48:03 +00:00
Trace.cpp Put the functionality for printing a value to a raw_ostream as an 2014-01-09 02:29:41 +00:00
TypeBasedAliasAnalysis.cpp [TBAA] Fix handling of mixed TBAA (path-aware and non-path-aware TBAA). 2014-05-03 22:32:52 +00:00
ValueTracking.cpp Teach isKnownNonNull that a nonnull return is not null. Add a test for this case as well as the case of a nonnull attribute (already handled but not tested). 2014-05-20 05:13:21 +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))

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