llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-11-05 13:09:10 +00:00

History

Tobias Grosser 75c86c9e9a [C++11] Add a basic block range view for RegionInfo This also switches the users in LLVM to ensure this functionality is tested. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202705 91177308-0d34-0410-b5e6-96231b3b80d8		2014-03-03 13:00:39 +00:00
..
IPA	[C++11] Replace llvm::tie with std::tie.	2014-03-02 13:30:33 +00:00
AliasAnalysis.cpp	Make DataLayout a plain object, not a pass.	2014-02-25 17:30:31 +00:00
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp
AliasSetTracker.cpp
Analysis.cpp
BasicAliasAnalysis.cpp	Rename a few more DataLayout variables from TD to DL.	2014-02-21 18:34:28 +00:00
BlockFrequencyInfo.cpp
BranchProbabilityInfo.cpp
CaptureTracking.cpp
CFG.cpp	Make succ_iterator a real random access iterator and clean up a couple of users.	2014-02-10 14:17:42 +00:00
CFGPrinter.cpp	Replace the F_Binary flag with a F_Text one.	2014-02-24 18:20:12 +00:00
CMakeLists.txt	[PM] Add a new "lazy" call graph analysis pass for the new pass manager.	2014-02-06 04:37:03 +00:00
CodeMetrics.cpp
ConstantFolding.cpp
CostModel.cpp	[C++11] Replace llvm::tie with std::tie.	2014-03-02 13:30:33 +00:00
Delinearization.cpp
DependenceAnalysis.cpp	normalize the last delinearized dimension	2014-02-21 18:15:11 +00:00
DominanceFrontier.cpp
DomPrinter.cpp
InstCount.cpp
InstructionSimplify.cpp	Rename many DataLayout variables from TD to DL.	2014-02-21 00:06:31 +00:00
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp	Make DataLayout a plain object, not a pass.	2014-02-25 17:30:31 +00:00
LazyCallGraph.cpp	[C++11] Add two range adaptor views to User: operands and	2014-03-03 10:42:58 +00:00
LazyValueInfo.cpp	Make DataLayout a plain object, not a pass.	2014-02-25 17:30:31 +00:00
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp	[C++11] Replace llvm::next and llvm::prior with std::next and std::prev.	2014-03-02 12:27:27 +00:00
LLVMBuild.txt
Loads.cpp
LoopInfo.cpp	[C++11] Replace llvm::next and llvm::prior with std::next and std::prev.	2014-03-02 12:27:27 +00:00
LoopPass.cpp	Constify the Optnone checks in IR passes.	2014-02-26 01:23:26 +00:00
Makefile
MemDepPrinter.cpp
MemoryBuiltins.cpp
MemoryDependenceAnalysis.cpp	[C++11] Replace llvm::next and llvm::prior with std::next and std::prev.	2014-03-02 12:27:27 +00:00
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp	Make DataLayout a plain object, not a pass.	2014-02-25 17:30:31 +00:00
PHITransAddr.cpp	Rename some member variables from TD to DL.	2014-02-18 15:33:12 +00:00
PostDominators.cpp
PtrUseVisitor.cpp	[C++11] Switch all uses of the llvm_move macro to use std::move	2014-03-02 04:08:41 +00:00
README.txt
RegionInfo.cpp	[C++11] Add a basic block range view for RegionInfo	2014-03-03 13:00:39 +00:00
RegionPass.cpp	[C++11] Add a basic block range view for RegionInfo	2014-03-03 13:00:39 +00:00
RegionPrinter.cpp	[C++11] Add a basic block range view for RegionInfo	2014-03-03 13:00:39 +00:00
ScalarEvolution.cpp	[C++11] Replace llvm::next and llvm::prior with std::next and std::prev.	2014-03-02 12:27:27 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp	[C++11] Replace llvm::next and llvm::prior with std::next and std::prev.	2014-03-02 12:27:27 +00:00
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp
TargetTransformInfo.cpp	Switch all uses of LLVM_OVERRIDE to just use 'override' directly.	2014-03-02 09:09:27 +00:00
Trace.cpp
TypeBasedAliasAnalysis.cpp
ValueTracking.cpp

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))

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