llvm-6502

mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-09-30 19:55:11 +00:00

History

Paul Robinson 2684ddd72e Disable most IR-level transform passes on functions marked 'optnone'. Ideally only those transform passes that run at -O0 remain enabled, in reality we get as close as we reasonably can. Passes are responsible for disabling themselves, it's not the job of the pass manager to do it for them. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200892 91177308-0d34-0410-b5e6-96231b3b80d8		2014-02-06 00:07:05 +00:00
..
IPA	cleanup: scc_iterator consumers should use isAtEnd	2014-02-04 19:19:07 +00:00
AliasAnalysis.cpp	[cleanup] Move the Dominators.h and Verifier.h headers into the IR	2014-01-13 09:26:24 +00:00
AliasAnalysisCounter.cpp	Put the functionality for printing a value to a raw_ostream as an	2014-01-09 02:29:41 +00:00
AliasAnalysisEvaluator.cpp	Put the functionality for printing a value to a raw_ostream as an	2014-01-09 02:29:41 +00:00
AliasDebugger.cpp
AliasSetTracker.cpp	Put the functionality for printing a value to a raw_ostream as an	2014-01-09 02:29:41 +00:00
Analysis.cpp	[PM] Make the verifier work independently of any pass manager.	2014-01-19 02:22:18 +00:00
BasicAliasAnalysis.cpp	Fix known typos	2014-01-24 17:20:08 +00:00
BlockFrequencyInfo.cpp
BranchProbabilityInfo.cpp
CaptureTracking.cpp	Make nocapture analysis work with addrspacecast	2014-01-14 19:11:52 +00:00
CFG.cpp	[cleanup] Move the Dominators.h and Verifier.h headers into the IR	2014-01-13 09:26:24 +00:00
CFGPrinter.cpp
CMakeLists.txt
CodeMetrics.cpp
ConstantFolding.cpp
CostModel.cpp	Get right cost for addrspacecast in cost model	2014-01-22 20:30:16 +00:00
Delinearization.cpp
DependenceAnalysis.cpp	Fix known typos	2014-01-24 17:20:08 +00:00
DominanceFrontier.cpp	[PM] Split DominatorTree into a concrete analysis result object which	2014-01-13 13:07:17 +00:00
DomPrinter.cpp	[PM] Split DominatorTree into a concrete analysis result object which	2014-01-13 13:07:17 +00:00
InstCount.cpp
InstructionSimplify.cpp	InstSimplify: Make shift, select and GEP simplifications vector-aware.	2014-01-24 17:09:53 +00:00
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp	[PM] Split DominatorTree into a concrete analysis result object which	2014-01-13 13:07:17 +00:00
LazyValueInfo.cpp
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp	[PM] Split DominatorTree into a concrete analysis result object which	2014-01-13 13:07:17 +00:00
LLVMBuild.txt
Loads.cpp
LoopInfo.cpp	[PM] Split DominatorTree into a concrete analysis result object which	2014-01-13 13:07:17 +00:00
LoopPass.cpp	Disable most IR-level transform passes on functions marked 'optnone'.	2014-02-06 00:07:05 +00:00
Makefile
MemDepPrinter.cpp	Put the functionality for printing a value to a raw_ostream as an	2014-01-09 02:29:41 +00:00
MemoryBuiltins.cpp	Update optimization passes to handle inalloca arguments	2014-01-28 02:38:36 +00:00
MemoryDependenceAnalysis.cpp	[PM] Split DominatorTree into a concrete analysis result object which	2014-01-13 13:07:17 +00:00
ModuleDebugInfoPrinter.cpp	Put the functionality for printing a value to a raw_ostream as an	2014-01-09 02:29:41 +00:00
NoAliasAnalysis.cpp
PHITransAddr.cpp	[cleanup] Move the Dominators.h and Verifier.h headers into the IR	2014-01-13 09:26:24 +00:00
PostDominators.cpp	[PM] Pull the generic graph algorithms and data structures for dominator	2014-01-13 10:52:56 +00:00
PtrUseVisitor.cpp
README.txt
RegionInfo.cpp	[PM] Split DominatorTree into a concrete analysis result object which	2014-01-13 13:07:17 +00:00
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp	Fix crasher introduced in r200203 and caught by a libc++ buildbot. Don't assume that getMulExpr returns a SCEVMulExpr, it may have simplified it to something else!	2014-01-27 10:47:44 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp	[cleanup] Move the Dominators.h and Verifier.h headers into the IR	2014-01-13 09:26:24 +00:00
ScalarEvolutionNormalization.cpp	[cleanup] Move the Dominators.h and Verifier.h headers into the IR	2014-01-13 09:26:24 +00:00
SparsePropagation.cpp
TargetTransformInfo.cpp	Revert "Revert "Add Constant Hoisting Pass" (r200034)"	2014-01-25 02:02:55 +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
ValueTracking.cpp	Allow speculating llvm.sqrt, fma and fmuladd	2014-01-31 00:09:00 +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))

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