llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-28 04:33:05 +00:00

History

Chandler Carruth bc65a8d518 Move the LLVM IR asm writer header files into the IR directory, as they are part of the core IR library in order to support dumping and other basic functionality. Rename the 'Assembly' include directory to 'AsmParser' to match the library name and the only functionality left their -- printing has been in the core IR library for quite some time. Update all of the #includes to match. All of this started because I wanted to have the layering in good shape before I started adding support for printing LLVM IR using the new pass infrastructure, and commandline support for the new pass infrastructure. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198688 91177308-0d34-0410-b5e6-96231b3b80d8		2014-01-07 12:34:26 +00:00
..
IPA	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
AliasAnalysis.cpp
AliasAnalysisCounter.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
AliasAnalysisEvaluator.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
AliasDebugger.cpp
AliasSetTracker.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
Analysis.cpp
BasicAliasAnalysis.cpp
BlockFrequencyInfo.cpp
BranchProbabilityInfo.cpp
CaptureTracking.cpp
CFG.cpp
CFGPrinter.cpp
CMakeLists.txt
CodeMetrics.cpp
ConstantFolding.cpp
CostModel.cpp
Delinearization.cpp
DependenceAnalysis.cpp
DominanceFrontier.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
DomPrinter.cpp
InstCount.cpp
InstructionSimplify.cpp
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
LazyValueInfo.cpp
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
LLVMBuild.txt
Loads.cpp
LoopInfo.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
LoopPass.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
Makefile
MemDepPrinter.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
MemoryBuiltins.cpp
MemoryDependenceAnalysis.cpp
ModuleDebugInfoPrinter.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
NoAliasAnalysis.cpp
PHITransAddr.cpp
PostDominators.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
PtrUseVisitor.cpp
README.txt
RegionInfo.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp
TargetTransformInfo.cpp
Trace.cpp	Move the LLVM IR asm writer header files into the IR directory, as they	2014-01-07 12:34:26 +00:00
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))

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