llvm-6502/lib/Analysis
Bill Wendling d58b50b99b A limit of 500 was still a bit too high for some tests.
PR15000 has a testcase where the time to compile was bordering on 30s. When I
dropped the limit value to 100, it became a much more managable 6s. The compile
time seems to increase in a roughly linear fashion based on increasing the limit
value. (See the runtimes below.)

So, let's lower the limit to 100 so that they can get a more reasonable compile
time.

Limit Value  Time
-----------  ----
10           0.9744s
20           1.8035s
30           2.3618s
40           2.9814s
50           3.6988s
60           4.5486s
70           4.9314s
80           5.8012s
90           6.4246s
100          7.0852s
110          7.6634s
120          8.3553s
130          9.0552s
140          9.6820s
150          9.8804s
160         10.8901s
170         10.9855s
180         12.0114s
190         12.6816s
200         13.2754s
210         13.9942s
220         13.8097s
230         14.3272s
240         15.7753s
250         15.6673s
260         16.0541s
270         16.7625s
280         17.3823s
290         18.8213s
300         18.6120s
310         20.0333s
320         19.5165s
330         20.2505s
340         20.7068s
350         21.1833s
360         22.9216s
370         22.2152s
380         23.9390s
390         23.4609s
400         24.0426s
410         24.6410s
420         26.5208s
430         27.7155s
440         26.4142s
450         28.5646s
460         27.3494s
470         29.7255s
480         29.4646s
490         30.5001s


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179713 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-17 20:02:32 +00:00
..
IPA ArrayRef ca accept one element. Simplify code a little bit, also it matches now 2013-03-07 20:01:19 +00:00
AliasAnalysis.cpp Move isKnownNonNull out of AliasAnalysis.h and into ValueTracking.cpp since 2013-01-31 02:40:59 +00:00
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp Support in AAEvaluator to print alias queries of loads/stores with TBAA tags. 2013-03-22 22:34:41 +00:00
AliasDebugger.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
AliasSetTracker.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
Analysis.cpp Remove -print-dbginfo as it is unused & bitrotten. 2013-03-08 18:17:46 +00:00
BasicAliasAnalysis.cpp Revert r176408 and r176407 to address PR15540. 2013-04-09 18:16:05 +00:00
BlockFrequencyInfo.cpp
BranchProbabilityInfo.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
CaptureTracking.cpp Remove unneeded #includes. Use forward declarations instead. 2013-03-10 00:34:01 +00:00
CFGPrinter.cpp
CMakeLists.txt Remove -print-dbginfo as it is unused & bitrotten. 2013-03-08 18:17:46 +00:00
CodeMetrics.cpp Begin fleshing out an interface in TTI for modelling the costs of 2013-01-22 11:26:02 +00:00
ConstantFolding.cpp Fix a scalability issue with complex ConstantExprs. 2013-04-13 12:53:18 +00:00
CostModel.cpp CostModel: Add parameter to instruction cost to further classify operand values 2013-04-04 23:26:21 +00:00
DependenceAnalysis.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
DominanceFrontier.cpp
DomPrinter.cpp
InstCount.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
InstructionSimplify.cpp InstructionSimplify.cpp: Fix a ligature, "fi", to get rid of utf8 in comment. 2013-04-08 23:05:21 +00:00
Interval.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
IntervalPartition.cpp
IVUsers.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
LazyValueInfo.cpp Move isKnownNonNull out of AliasAnalysis.h and into ValueTracking.cpp since 2013-01-31 02:40:59 +00:00
LibCallAliasAnalysis.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
LibCallSemantics.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
Lint.cpp Change GetPointerBaseWithConstantOffset's DataLayout argument from a 2013-01-31 02:00:45 +00:00
LLVMBuild.txt
Loads.cpp Change GetPointerBaseWithConstantOffset's DataLayout argument from a 2013-01-31 02:00:45 +00:00
LoopInfo.cpp Metadata for annotating loops as parallel. The first consumer for this 2013-02-13 18:08:57 +00:00
LoopPass.cpp
Makefile
MemDepPrinter.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
MemoryBuiltins.cpp Revert r176408 and r176407 to address PR15540. 2013-04-09 18:16:05 +00:00
MemoryDependenceAnalysis.cpp A limit of 500 was still a bit too high for some tests. 2013-04-17 20:02:32 +00:00
ModuleDebugInfoPrinter.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
NoAliasAnalysis.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
PathNumbering.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
PathProfileInfo.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
PathProfileVerifier.cpp Build fixes for STLPort + GCC 2013-03-29 18:48:45 +00:00
PHITransAddr.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
PostDominators.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
ProfileDataLoader.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
ProfileDataLoaderPass.cpp Revert "Add LLVMContext::emitWarning methods and use them. <rdar://problem/12867368>" 2013-02-08 21:48:29 +00:00
ProfileEstimatorPass.cpp
ProfileInfo.cpp Build fixes for STLPort + GCC 2013-03-29 18:48:45 +00:00
ProfileInfoLoader.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
ProfileInfoLoaderPass.cpp Revert "Add LLVMContext::emitWarning methods and use them. <rdar://problem/12867368>" 2013-02-08 21:48:29 +00:00
ProfileVerifierPass.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
PtrUseVisitor.cpp Hoist the GEP constant address offset computation to a common home on 2012-12-11 10:29:10 +00:00
README.txt
RegionInfo.cpp RegionInfo: Add helpers to replace entry/exit recursively 2013-04-10 06:54:49 +00:00
RegionPass.cpp
RegionPrinter.cpp
ScalarEvolution.cpp Fix SCEV forgetMemoizedResults should search and destroy backedge exprs. 2013-03-26 03:14:53 +00:00
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp SCEVExpander fix. RAUW needs to update the InsertedExpressions cache. 2013-01-14 21:00:37 +00:00
ScalarEvolutionNormalization.cpp
SparsePropagation.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
TargetTransformInfo.cpp CostModel: Add parameter to instruction cost to further classify operand values 2013-04-04 23:26:21 +00:00
Trace.cpp Move all of the header files which are involved in modelling the LLVM IR 2013-01-02 11:36:10 +00:00
TypeBasedAliasAnalysis.cpp Aliasing rules for struct-path aware TBAA. 2013-04-11 23:24:18 +00:00
ValueTracking.cpp Check whether a pointer is non-null (isKnownNonNull) in isKnownNonZero. 2013-03-18 21:23:25 +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))

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