llvm-6502/lib/Analysis
Adam Nemet 2261a25f88 [LAA] Split out a helper to print a collection of memchecks
This is effectively an NFC but we can no longer print the index of the
pointer group so instead I print its address.  This still lets us
cross-check the section that list the checks against the section that
list the groups (see how I modified the test).

E.g. before we printed this:

    Run-time memory checks:
    Check 0:
      Comparing group 0:
        %arrayidxC = getelementptr inbounds i16, i16* %c, i64 %store_ind
        %arrayidxC1 = getelementptr inbounds i16, i16* %c, i64 %store_ind_inc
      Against group 1:
        %arrayidxA = getelementptr i16, i16* %a, i64 %ind
        %arrayidxA1 = getelementptr i16, i16* %a, i64 %add
    ...
    Grouped accesses:
      Group 0:
        (Low: %c High: (78 + %c))
          Member: {%c,+,4}<%for.body>
          Member: {(2 + %c),+,4}<%for.body>

Now we print this (changes are underlined):

    Run-time memory checks:
    Check 0:
      Comparing group (0x7f9c6040c320):
                       ~~~~~~~~~~~~~~
        %arrayidxC1 = getelementptr inbounds i16, i16* %c, i64 %store_ind_inc
        %arrayidxC = getelementptr inbounds i16, i16* %c, i64 %store_ind
      Against group (0x7f9c6040c358):
                     ~~~~~~~~~~~~~~
        %arrayidxA1 = getelementptr i16, i16* %a, i64 %add
        %arrayidxA = getelementptr i16, i16* %a, i64 %ind
    ...
    Grouped accesses:
      Group 0x7f9c6040c320:
            ~~~~~~~~~~~~~~
        (Low: %c High: (78 + %c))
          Member: {(2 + %c),+,4}<%for.body>
          Member: {%c,+,4}<%for.body>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243354 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-27 23:54:41 +00:00
..
IPA [GMR] Switch the function info we store for every function to be a much 2015-07-23 07:50:52 +00:00
AliasAnalysis.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
AliasAnalysisCounter.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
AliasAnalysisEvaluator.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
AliasDebugger.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
AliasSetTracker.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
Analysis.cpp Create a wrapper pass for BranchProbabilityInfo. 2015-07-15 22:48:29 +00:00
AssumptionCache.cpp [PM] Actually add the new pass manager support for the assumption cache. 2015-01-22 21:53:09 +00:00
BasicAliasAnalysis.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
BlockFrequencyInfo.cpp Add new constructors for LoopInfo/DominatorTree/BFI/BPI 2015-07-16 23:23:35 +00:00
BlockFrequencyInfoImpl.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
BranchProbabilityInfo.cpp Create a wrapper pass for BranchProbabilityInfo. 2015-07-15 22:48:29 +00:00
CaptureTracking.cpp [CaptureTracking] Avoid long compilation time on large basic blocks 2015-06-24 17:53:17 +00:00
CFG.cpp [CaptureTracking] Avoid long compilation time on large basic blocks 2015-06-24 17:53:17 +00:00
CFGPrinter.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
CFLAliasAnalysis.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
CGSCCPassManager.cpp [PM] Remove the defunt CGSCC-specific debug flag. 2015-01-13 22:45:13 +00:00
CMakeLists.txt Move VectorUtils from Transforms to Analysis to correct layering violation 2015-06-26 18:02:52 +00:00
CodeMetrics.cpp Re-sort includes with sort-includes.py and insert raw_ostream.h where it's used. 2015-03-23 19:32:43 +00:00
ConstantFolding.cpp Fix assert when inlining a constantexpr addrspacecast 2015-07-27 18:31:03 +00:00
CostModel.cpp Roll forward r243250 2015-07-26 19:10:03 +00:00
Delinearization.cpp Move delinearization from SCEVAddRecExpr to ScalarEvolution 2015-06-29 14:42:48 +00:00
DependenceAnalysis.cpp Move delinearization from SCEVAddRecExpr to ScalarEvolution 2015-06-29 14:42:48 +00:00
DivergenceAnalysis.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
DominanceFrontier.cpp Templatify DominanceFrontier. 2014-07-12 21:59:52 +00:00
DomPrinter.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
InstCount.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
InstructionSimplify.cpp [InstSimplify] Teach InstSimplify how to simplify extractelement 2015-07-13 01:15:53 +00:00
Interval.cpp Revert "[C++11] Add predecessors(BasicBlock *) / successors(BasicBlock *) iterator ranges." 2014-07-21 17:06:51 +00:00
IntervalPartition.cpp
IteratedDominanceFrontier.cpp Move IDF Calculation to a separate file, expose an interface to it. 2015-04-21 19:13:02 +00:00
IVUsers.cpp [LSR] don't attempt to promote ephemeral values to indvars 2015-07-13 03:28:53 +00:00
LazyCallGraph.cpp Revert r225854: [PM] Move the LazyCallGraph printing functionality to 2015-01-14 00:27:45 +00:00
LazyValueInfo.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
LibCallAliasAnalysis.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
LibCallSemantics.cpp Move the personality function from LandingPadInst to Function 2015-06-17 20:52:32 +00:00
Lint.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
LLVMBuild.txt Update libdeps since TLI was moved from Target to Analysis in r226078. 2015-01-15 05:21:00 +00:00
Loads.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
LoopAccessAnalysis.cpp [LAA] Split out a helper to print a collection of memchecks 2015-07-27 23:54:41 +00:00
LoopInfo.cpp Add new constructors for LoopInfo/DominatorTree/BFI/BPI 2015-07-16 23:23:35 +00:00
LoopPass.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
Makefile
MemDepPrinter.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
MemDerefPrinter.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
MemoryBuiltins.cpp DataLayout is mandatory, update the API to reflect it with references. 2015-03-10 02:37:25 +00:00
MemoryDependenceAnalysis.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
MemoryLocation.cpp [PM/AA] Split the location computation out of getArgLocation so the 2015-06-17 07:12:40 +00:00
ModuleDebugInfoPrinter.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
NoAliasAnalysis.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
PHITransAddr.cpp [GVN] Set proper debug locations for some instructions created by GVN. 2015-06-10 17:37:38 +00:00
PostDominators.cpp
PtrUseVisitor.cpp Update SetVector to rely on the underlying set's insert to return a pair<iterator, bool> 2014-11-19 07:49:26 +00:00
README.txt
RegionInfo.cpp [cleanup] Re-sort all the #include lines in LLVM using 2015-01-14 11:23:27 +00:00
RegionPass.cpp Change range-based for-loops to be -Wrange-loop-analysis clean. 2015-04-15 01:21:15 +00:00
RegionPrinter.cpp Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
ScalarEvolution.cpp [IndVars] Make loop varying predicates loop invariant. 2015-07-27 21:42:49 +00:00
ScalarEvolutionAliasAnalysis.cpp [PM/AA] Hoist the AliasResult enum out of the AliasAnalysis class. 2015-06-22 02:16:51 +00:00
ScalarEvolutionExpander.cpp [LSR] canonicalize Prod*(1<<C) to Prod<<C 2015-06-24 19:28:40 +00:00
ScalarEvolutionNormalization.cpp Fix typos in comments, NFC 2014-08-29 21:53:01 +00:00
ScopedNoAliasAA.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
SparsePropagation.cpp
StratifiedSets.h Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
TargetLibraryInfo.cpp Populate list of vectorizable functions for Accelerate library. 2015-05-07 17:11:51 +00:00
TargetTransformInfo.cpp [TargetTransformInfo][NFCI] Add TargetTransformInfo::isZExtFree. 2015-07-27 23:27:43 +00:00
Trace.cpp
TypeBasedAliasAnalysis.cpp [PM/AA] Extract the ModRef enums from the AliasAnalysis class in 2015-07-22 23:15:57 +00:00
ValueTracking.cpp IR: Do not consider available_externally linkage to be linker-weak. 2015-07-05 20:52:35 +00:00
VectorUtils.cpp [InstSimplify] Teach InstSimplify how to simplify extractelement 2015-07-13 01:15:53 +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))

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