llvm-project

History

Nick Lewycky c1f8658368 Add C++ global operator {new,new[],delete,delete[]}(unsigned {int,long}) to the memory builtins as equivalent to malloc/free. This is different from any attribute we have. For example, you can delete the allocators when their result is unused, but you can't collapse two calls to the same function, even if no global/memory state has changed in between. The noalias return states that the result does not alias any other pointer, but instcombine optimizes malloc() as though the result is non-null for the purpose of eliminating unused pointers. llvm-svn: 127673		2011-03-15 07:31:32 +00:00
..
IPA	Use the new addEscapingValue callback to update GlobalsModRef when GVN adds PHIs of GEPs. For the moment,	2011-01-03 23:51:43 +00:00
AliasAnalysis.cpp	Stub out a new updating interface to AliasAnalysis, allowing stateful analyses to be informed when	2011-01-03 21:38:41 +00:00
AliasAnalysisCounter.cpp	Teach AliasAnalysisCounter about PartialAlias.	2010-12-10 19:53:05 +00:00
AliasAnalysisEvaluator.cpp	Teach AliasAnalysisEvaluator about PartialAlias.	2010-12-10 19:52:40 +00:00
AliasDebugger.cpp	Extend the AliasAnalysis::pointsToConstantMemory interface to allow it	2010-11-08 16:45:26 +00:00
AliasSetTracker.cpp	Update this code to handle PartialAlias as MayAlias.	2010-12-10 19:40:47 +00:00
Analysis.cpp	Delete the LiveValues pass. I won't get get back to the project it	2011-02-28 19:37:59 +00:00
BasicAliasAnalysis.cpp	Give GetUnderlyingObject a TargetData, to keep it in sync	2011-01-24 18:53:32 +00:00
CFGPrinter.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
CMakeLists.txt	Unbreak CMake build.	2011-03-01 00:02:51 +00:00
CaptureTracking.cpp	VAArg doesn't capture its operand.	2010-11-09 20:09:35 +00:00
ConstantFolding.cpp	convert ConstantVector::get to use ArrayRef.	2011-02-15 00:14:00 +00:00
DIBuilder.cpp	Today, the language front ends produces llvm.dbg.* intrinsics, used to encode arguments' debug info, in order any way, most of the times. However, if a front end mix-n-matches llvm.dbg.declare and llvm.dbg.value intrinsics to encode debug info for arguments then code generator needs a way to find argument order.	2011-03-01 22:58:13 +00:00
DbgInfoPrinter.cpp	Move DbgInfoPrinter specific utlities inside DbgInfoPrinter.cpp	2011-02-15 17:36:11 +00:00
DebugInfo.cpp	Remove DIFactory. Patch by Devang.	2011-03-02 20:30:37 +00:00
DomPrinter.cpp	split dom frontier handling stuff out to its own DominanceFrontier header,	2011-01-02 22:09:33 +00:00
DominanceFrontier.cpp	Move DominanceFrontier from VMCore to Analysis.	2011-01-18 06:06:27 +00:00
IVUsers.cpp	split dom frontier handling stuff out to its own DominanceFrontier header,	2011-01-02 22:09:33 +00:00
InlineCost.cpp	Remove premature optimization that avoided calculating argument weights	2011-02-06 21:27:46 +00:00
InstCount.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
InstructionSimplify.cpp	Fix two cases I forgot to update when doing a mental "getSwappedPredicate".	2011-03-09 08:20:06 +00:00
Interval.cpp	Change Pass::print to take a raw ostream instead of std::ostream,	2009-08-23 06:03:38 +00:00
IntervalPartition.cpp	Now with fewer extraneous semicolons!	2010-10-07 22:25:06 +00:00
LazyValueInfo.cpp	Teach LazyValueInfo that allocas aren't NULL. Over all of llvm-test, this saves	2011-01-15 09:16:12 +00:00
LibCallAliasAnalysis.cpp	Now with fewer extraneous semicolons!	2010-10-07 22:25:06 +00:00
LibCallSemantics.cpp	Thread const correctness through a bunch of AliasAnalysis interfaces and	2010-08-03 21:48:53 +00:00
Lint.cpp	Give GetUnderlyingObject a TargetData, to keep it in sync	2011-01-24 18:53:32 +00:00
Loads.cpp	Move Value::getUnderlyingObject to be a standalone	2010-12-15 20:02:24 +00:00
LoopDependenceAnalysis.cpp	split dom frontier handling stuff out to its own DominanceFrontier header,	2011-01-02 22:09:33 +00:00
LoopInfo.cpp	Fix typo pointed out by Trevor Harmon.	2010-11-13 12:16:27 +00:00
LoopPass.cpp	Introduce DebugInfoProbe. This is used to monitor how llvm optimizer is treating debugging information.	2011-03-10 00:21:25 +00:00
Makefile	make -fno-rtti the default unless a directory builds with REQUIRES_RTTI.	2010-01-24 20:43:08 +00:00
MemDepPrinter.cpp	Add helper functions for computing the Location of load, store,	2010-11-11 21:50:19 +00:00
MemoryBuiltins.cpp	Add C++ global operator {new,new[],delete,delete[]}(unsigned {int,long}) to the	2011-03-15 07:31:32 +00:00
MemoryDependenceAnalysis.cpp	Give GetUnderlyingObject a TargetData, to keep it in sync	2011-01-24 18:53:32 +00:00
ModuleDebugInfoPrinter.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
NoAliasAnalysis.cpp	Use the new addEscapingValue callback to update GlobalsModRef when GVN adds PHIs of GEPs. For the moment,	2011-01-03 23:51:43 +00:00
PHITransAddr.cpp	split dom frontier handling stuff out to its own DominanceFrontier header,	2011-01-02 22:09:33 +00:00
PathNumbering.cpp	Implementation of path profiling.	2011-01-29 01:09:53 +00:00
PathProfileInfo.cpp	Implementation of path profiling.	2011-01-29 01:09:53 +00:00
PathProfileVerifier.cpp	Implementation of path profiling.	2011-01-29 01:09:53 +00:00
PostDominators.cpp	split dom frontier handling stuff out to its own DominanceFrontier header,	2011-01-02 22:09:33 +00:00
ProfileEstimatorPass.cpp	fix PR8928 by clearing a stale map, patch by Jakub Staszak!	2011-01-24 18:36:51 +00:00
ProfileInfo.cpp	Null initialize a few variables flagged by	2011-01-23 17:05:06 +00:00
ProfileInfoLoader.cpp	Reapplied r81355 with the problems fixed.	2009-09-16 11:35:50 +00:00
ProfileInfoLoaderPass.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
ProfileVerifierPass.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +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	Add single entry / single exit accessors.	2011-01-13 23:18:04 +00:00
RegionPass.cpp	Remove useless dynamic_cast<>().	2010-12-12 21:58:28 +00:00
RegionPrinter.cpp	RegionPrinter: Ignore back edges when layouting the graph	2011-02-27 04:11:07 +00:00
ScalarEvolution.cpp	Remove getMinusSCEVForExitTest().	2011-03-15 01:16:14 +00:00
ScalarEvolutionAliasAnalysis.cpp	Get rid of static constructors for pass registration. Instead, every pass exposes an initializeMyPassFunction(), which	2010-10-19 17:21:58 +00:00
ScalarEvolutionExpander.cpp	Added SCEV::NoWrapFlags to manage unsigned, signed, and self wrap	2011-03-14 16:50:06 +00:00
ScalarEvolutionNormalization.cpp	Added SCEV::NoWrapFlags to manage unsigned, signed, and self wrap	2011-03-14 16:50:06 +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	Update a comment.	2010-12-16 02:55:10 +00:00
ValueTracking.cpp	Teach ComputeMaskedBits about sub nsw.	2011-03-12 17:18:11 +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))

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