llvm-6502/lib/Analysis
Owen Anderson 6cd2075549 In the default address space, any GEP off of null results in a trap value if you try to load it. Thus,
any load in the default address space that completes implies that the base value that it GEP'd from
was not null.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112015 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-25 01:16:47 +00:00
..
IPA Now that PassInfo and Pass::ID have been separated, move the rest of the passes over to the new registration API. 2010-08-23 17:52:01 +00:00
AliasAnalysis.cpp Implement a proper getModRefInfo for va_arg. 2010-08-06 18:24:38 +00:00
AliasAnalysisCounter.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
AliasAnalysisEvaluator.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
AliasDebugger.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
AliasSetTracker.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
Analysis.cpp "In order to ease automatic bindings generation, it would be helpful if boolean values were distinguishable from integers. The attached patch introduces "typedef int LLVMBool;", and uses LLVMBool instead of int throughout the C API, wherever a boolean value is called for." 2010-01-09 22:27:07 +00:00
BasicAliasAnalysis.cpp refix PR1143 by making basicaa analyze zexts of indices aggresively, 2010-08-18 23:09:49 +00:00
CaptureTracking.cpp simplify 2010-07-28 10:57:28 +00:00
CFGPrinter.cpp Now that PassInfo and Pass::ID have been separated, move the rest of the passes over to the new registration API. 2010-08-23 17:52:01 +00:00
CMakeLists.txt Fix CMake build 2010-08-03 02:38:20 +00:00
ConstantFolding.cpp eliminate CallInst::ArgOffset 2010-07-16 09:38:02 +00:00
DbgInfoPrinter.cpp Convert DbgInfoPrinter to use errs() instead of outs(). 2010-08-20 18:03:05 +00:00
DebugInfo.cpp Let FE use derived types for DW_TAG_friend. 2010-08-23 23:16:25 +00:00
DomPrinter.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
InlineCost.cpp use ImmutableCallSite for const-corrgoodness 2010-07-27 14:15:29 +00:00
InstCount.cpp Revert r111082. No warnings for this common pattern. 2010-08-15 10:27:23 +00:00
InstructionSimplify.cpp Fix PR7647, handling the case when 'To' ends up being 2010-07-15 06:36:08 +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 Tweak IVUsers' concept of "interesting" to exclude add recurrences 2010-08-17 22:50:37 +00:00
LazyValueInfo.cpp In the default address space, any GEP off of null results in a trap value if you try to load it. Thus, 2010-08-25 01:16:47 +00:00
LibCallAliasAnalysis.cpp Thread const correctness through a bunch of AliasAnalysis interfaces and 2010-08-03 21:48:53 +00:00
LibCallSemantics.cpp Thread const correctness through a bunch of AliasAnalysis interfaces and 2010-08-03 21:48:53 +00:00
Lint.cpp Revert r111058, the lint check for indirectbr successors that aren't 2010-08-16 14:39:19 +00:00
LiveValues.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
Loads.cpp Move FindAvailableLoadedValue isSafeToLoadUnconditionally out of 2010-05-28 16:19:17 +00:00
LoopDependenceAnalysis.cpp Fix batch of converting RegisterPass<> to INTIALIZE_PASS(). 2010-07-21 22:09:45 +00:00
LoopInfo.cpp Eliminate getCanonicalInductionVariableIncrement's last user and 2010-07-23 21:34:51 +00:00
LoopPass.cpp Revert r111199; it breaks -debug-pass=Structure output. 2010-08-19 01:29:07 +00:00
Makefile make -fno-rtti the default unless a directory builds with REQUIRES_RTTI. 2010-01-24 20:43:08 +00:00
MemoryBuiltins.cpp minor enhancement to llvm::isFreeCall API: return CallInst; no functional change 2010-06-23 21:51:12 +00:00
MemoryDependenceAnalysis.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
ModuleDebugInfoPrinter.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
PHITransAddr.cpp Reapply r97010, the speculative revert failed. 2010-02-24 08:48:04 +00:00
PointerTracking.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
PostDominators.cpp Add INSTANTIATE_AG_PASS, which combines RegisterPass<> with RegisterAnalysisGroup<> for pass registration. 2010-07-21 23:07:00 +00:00
ProfileEstimatorPass.cpp Now that PassInfo and Pass::ID have been separated, move the rest of the passes over to the new registration API. 2010-08-23 17:52:01 +00:00
ProfileInfo.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
ProfileInfoLoader.cpp Reapplied r81355 with the problems fixed. 2009-09-16 11:35:50 +00:00
ProfileInfoLoaderPass.cpp Now that PassInfo and Pass::ID have been separated, move the rest of the passes over to the new registration API. 2010-08-23 17:52:01 +00:00
ProfileVerifierPass.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
README.txt When checking whether the special handling for an addrec increment which 2010-04-26 21:46:36 +00:00
RegionInfo.cpp RegionInfo: Do not assert if a BB is not part of the dominance tree. 2010-08-10 09:54:35 +00:00
RegionPrinter.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
ScalarEvolution.cpp To create a copy of a SmallVector with an element removed from the 2010-08-16 16:57:24 +00:00
ScalarEvolutionAliasAnalysis.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
ScalarEvolutionExpander.cpp Fix SCEVExpander::visitAddRecExpr so that it remembers the induction variable 2010-07-26 18:28:14 +00:00
ScalarEvolutionNormalization.cpp Fix SCEV denormalization of expressions where the exit value from 2010-07-20 17:06:20 +00:00
SparsePropagation.cpp Convert debug messages to use dbgs(). Generally this means 2009-12-23 22:28:01 +00:00
Trace.cpp Convert debug messages to use dbgs(). Generally this means 2009-12-23 22:35:10 +00:00
TypeBasedAliasAnalysis.cpp Reapply r110396, with fixes to appease the Linux buildbot gods. 2010-08-06 18:33:48 +00:00
ValueTracking.cpp move gep decomposition out of ValueTracking into BasicAA. The form of 2010-08-18 22:07:29 +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))

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