llvm-6502/lib/Analysis
Andrew Trick 5865a8dfde Fix a corner case in updating LoopInfo after fully unrolling an outer loop.
The loop tree's inclusive block lists are painful and expensive to
update. (I have no idea why they're inclusive). The design was
supposed to handle this case but the implementation missed it and my
unit tests weren't thorough enough.

Fixes PR11335: loop unroll update.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144970 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-18 03:42:41 +00:00
..
IPA build: Add initial cut at LLVMBuild.txt files. 2011-11-03 18:53:17 +00:00
AliasAnalysis.cpp Enhance alias analysis for atomic instructions a bit. Upgrade a couple alias-analysis tests to the new atomic instructions. 2011-09-26 20:15:28 +00:00
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
AliasDebugger.cpp
AliasSetTracker.cpp Atomic load/store support in LICM. 2011-08-15 20:52:09 +00:00
Analysis.cpp C API functions must be able to see their extern "C" definitions, or it will be impossible to call them from C. 2011-08-19 01:36:54 +00:00
BasicAliasAnalysis.cpp Remove the old atomic instrinsics. autoupgrade functionality is included with this patch. 2011-10-06 23:20:49 +00:00
BlockFrequencyInfo.cpp Add pass printing support to BlockFrequencyInfo pass. The implementation 2011-10-19 10:12:41 +00:00
BranchProbabilityInfo.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
CaptureTracking.cpp Refactor capture tracking (which already had a couple flags for whether returns 2011-11-14 22:49:42 +00:00
CFGPrinter.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
CMakeLists.txt Rewrite the CMake build to use explicit dependencies between libraries, 2011-07-29 00:14:25 +00:00
ConstantFolding.cpp Fixes following the CR by Chris and Duncan: 2011-08-29 19:58:36 +00:00
DbgInfoPrinter.cpp Fix for DbgInfoPrinter.cpp:174:12: warning: ‘LineNo’ may be used uninitialized in this function. 2011-09-21 23:34:23 +00:00
DebugInfo.cpp Update DebugInfoFinder to match recent debug info encoding changes. 2011-10-17 22:30:34 +00:00
DIBuilder.cpp Fix typo in comment. 2011-11-09 22:45:04 +00:00
DominanceFrontier.cpp
DomPrinter.cpp
InlineCost.cpp A FIXME about block addresses and indirectbr. 2011-10-20 04:05:33 +00:00
InstCount.cpp
InstructionSimplify.cpp Fix code to match comment. Fixes PR11340, a regression from r143209. 2011-11-08 21:08:02 +00:00
Interval.cpp
IntervalPartition.cpp
IVUsers.cpp Slightly more useful tracing. 2011-10-13 17:06:38 +00:00
LazyValueInfo.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
LibCallAliasAnalysis.cpp
LibCallSemantics.cpp
Lint.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
LLVMBuild.txt build: Add initial cut at LLVMBuild.txt files. 2011-11-03 18:53:17 +00:00
Loads.cpp Add some comments here because the lack of a check for volatile/atomic here is a bit unusual. 2011-08-15 21:56:39 +00:00
LoopDependenceAnalysis.cpp Misc analysis passes that need to be aware of atomic load/store. 2011-08-15 20:54:19 +00:00
LoopInfo.cpp Fix a corner case in updating LoopInfo after fully unrolling an outer loop. 2011-11-18 03:42:41 +00:00
LoopPass.cpp Reapply r138695. Fix PassManager stack depths. 2011-08-29 17:07:00 +00:00
Makefile
MemDepPrinter.cpp Enhance the memdep interface so that users can tell the difference between a dependency which cannot be calculated and a path reaching the entry point of the function. This patch introduces isNonFuncLocal, which replaces isUnknown in some cases. 2011-10-13 22:14:57 +00:00
MemoryBuiltins.cpp land David Blaikie's patch to de-constify Type, with a few tweaks. 2011-07-18 04:54:35 +00:00
MemoryDependenceAnalysis.cpp Refactor capture tracking (which already had a couple flags for whether returns 2011-11-14 22:49:42 +00:00
ModuleDebugInfoPrinter.cpp
NoAliasAnalysis.cpp
PathNumbering.cpp Add this back in for now. There are still a few passes which create unwind instructions at the moment. 2011-08-03 01:07:57 +00:00
PathProfileInfo.cpp
PathProfileVerifier.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
PHITransAddr.cpp Shorten some expressions by using ArrayRef::slice(). 2011-07-25 15:13:01 +00:00
PostDominators.cpp remove postdom frontiers, because it is dead. Forward dom frontiers are 2011-04-05 21:57:17 +00:00
ProfileEstimatorPass.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
ProfileInfo.cpp Fix a ton of comment typos found by codespell. Patch by 2011-04-15 05:18:47 +00:00
ProfileInfoLoader.cpp Remove unused STL header includes. 2011-04-23 19:53:52 +00:00
ProfileInfoLoaderPass.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
ProfileVerifierPass.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
README.txt
RegionInfo.cpp Missed some users of Value::getNameStr. 2011-11-15 18:30:06 +00:00
RegionPass.cpp Reapply r138695. Fix PassManager stack depths. 2011-08-29 17:07:00 +00:00
RegionPrinter.cpp
ScalarEvolution.cpp Fix SCEV overly optimistic back edge taken count for multi-exit loops. 2011-11-16 00:52:40 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp Fix SCEVExpander assert during LSR: "argument of incompatible type". 2011-10-15 06:19:55 +00:00
ScalarEvolutionNormalization.cpp Fix memory corruption I introduced a few checkins ago. 2011-10-13 18:49:23 +00:00
SparsePropagation.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
Trace.cpp Remove all remaining uses of Value::getNameStr(). 2011-11-15 16:27:03 +00:00
TypeBasedAliasAnalysis.cpp Fix a ton of comment typos found by codespell. Patch by 2011-04-15 05:18:47 +00:00
ValueTracking.cpp A shift of a power of two is a power of two or zero. 2011-10-28 18:30:05 +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))

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