llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-17 18:31:04 +00:00

History

Eli Friedman 39e30124e5 PR7959: Handle negative scales in GEPs correctly in BasicAA for non-64-bit targets. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114015 91177308-0d34-0410-b5e6-96231b3b80d8		2010-09-15 20:08:03 +00:00
..
IPA	Remove the experimental AliasAnalysis::getDependency interface, which	2010-09-14 21:25:10 +00:00
AliasAnalysis.cpp	Remove the experimental AliasAnalysis::getDependency interface, which	2010-09-14 21:25:10 +00:00
AliasAnalysisCounter.cpp	Remove the experimental AliasAnalysis::getDependency interface, which	2010-09-14 21:25:10 +00:00
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp	Remove the experimental AliasAnalysis::getDependency interface, which	2010-09-14 21:25:10 +00:00
AliasSetTracker.cpp
Analysis.cpp
BasicAliasAnalysis.cpp	PR7959: Handle negative scales in GEPs correctly in BasicAA for non-64-bit	2010-09-15 20:08:03 +00:00
CaptureTracking.cpp
CFGPrinter.cpp
CMakeLists.txt	Revert "CMake: Get rid of LLVMLibDeps.cmake and export the libraries normally."	2010-09-13 23:59:48 +00:00
ConstantFolding.cpp
DbgInfoPrinter.cpp
DebugInfo.cpp
DomPrinter.cpp
InlineCost.cpp	What the loop unroller cares about, rather than just not unrolling loops with calls, is	2010-09-09 20:32:23 +00:00
InstCount.cpp
InstructionSimplify.cpp	Teach InstructionSimplify to fold (A & B) & A -> A & B and (A \| B) \| A -> A \| B.	2010-09-10 22:39:55 +00:00
Interval.cpp
IntervalPartition.cpp	Reapply r110396, with fixes to appease the Linux buildbot gods.	2010-08-06 18:33:48 +00:00
IVUsers.cpp
LazyValueInfo.cpp	Clean up some of the PassRegistry implementation, and pImpl-ize it to reduce #include clutter	2010-09-07 19:16:25 +00:00
LibCallAliasAnalysis.cpp	Remove the experimental AliasAnalysis::getDependency interface, which	2010-09-14 21:25:10 +00:00
LibCallSemantics.cpp
Lint.cpp
LiveValues.cpp
Loads.cpp
LoopDependenceAnalysis.cpp
LoopInfo.cpp
LoopPass.cpp
Makefile
MemoryBuiltins.cpp
MemoryDependenceAnalysis.cpp	cleanup some of the lifetime/invariant marker stuff, add a big fixme.	2010-09-06 03:58:04 +00:00
ModuleDebugInfoPrinter.cpp
PHITransAddr.cpp
PointerTracking.cpp
PostDominators.cpp
ProfileEstimatorPass.cpp
ProfileInfo.cpp
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp
ProfileVerifierPass.cpp
README.txt
RegionInfo.cpp
RegionPrinter.cpp
ScalarEvolution.cpp
ScalarEvolutionAliasAnalysis.cpp	Remove the experimental AliasAnalysis::getDependency interface, which	2010-09-14 21:25:10 +00:00
ScalarEvolutionExpander.cpp
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp
Trace.cpp
TypeBasedAliasAnalysis.cpp	Convert TBAA to use the new TBAATag field of AliasAnalysis::Location.	2010-09-14 23:28:12 +00:00
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))

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