Daniel Neilson f7dd8e2ac0 [SCEV] Ensure ScalarEvolution::createAddRecFromPHIWithCastsImpl properly handles out of range truncations of the start and accum values ...

Summary:
 When constructing the predicate P1 in ScalarEvolution::createAddRecFromPHIWithCastsImpl() it is possible
for the PHISCEV from which the predicate is constructed to be a SCEVConstant instead of a SCEVAddRec. If
this happens, then the cast<SCEVAddRec>(PHISCEV) in the code will assert.

 Such a PHISCEV is possible if either the start value or the accumulator value is a constant value
that not equal to its truncated value, and if the truncated value is zero.

 This patch adds tests that demonstrate the cast<> assertion, and fixes this problem by checking
whether the PHISCEV is a constant before constructing the P1 predicate; if it is, then P1 is
equivalent to one of P2 or P3. Additionally, if we know that the start value or accumulator
value are constants then we check whether the P2 and/or P3 predicates are known false at compile
time; if either is, then we bail out of constructing the AddRec.

Reviewers: sanjoy, mkazantsev, silviu.baranga

Reviewed By: mkazantsev

Subscribers: mkazantsev, llvm-commits

Differential Revision: https://reviews.llvm.org/D37265

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312568 91177308-0d34-0410-b5e6-96231b3b80d8

2017-09-05 19:54:03 +00:00

..

AliasAnalysisTest.cpp

Allow None as a MemoryLocation to getModRefInfo

2017-08-01 00:28:29 +00:00

AliasSetTrackerTest.cpp

[AST] Fix a bug in aliasesUnknownInst. Make sure we are comparing the unknown instructions in the alias set and the instruction interested in.

2017-06-25 12:55:11 +00:00

BlockFrequencyInfoTest.cpp

Add an interface to scale the frequencies of a set of blocks.

2017-01-19 18:53:16 +00:00

BranchProbabilityInfoTest.cpp

Re-sort #include lines for unittests. This uses a slightly modified

2017-06-06 11:06:56 +00:00

CallGraphTest.cpp

[GraphTraits] Replace all NodeType usage with NodeRef

2016-08-22 21:09:30 +00:00

CFGTest.cpp

Re-sort #include lines for unittests. This uses a slightly modified

2017-06-06 11:06:56 +00:00

CGSCCPassManagerTest.cpp

[PM] Switch the CGSCC debug messages to use the standard LLVM debug

2017-08-11 05:47:13 +00:00

CMakeLists.txt

[AST] Fix a bug in aliasesUnknownInst. Make sure we are comparing the unknown instructions in the alias set and the instruction interested in.

2017-06-25 12:55:11 +00:00

GlobalsModRefTest.cpp

GlobalsModRef: Ensure optnone+readonly/readnone attributes are respected

2017-06-07 21:37:39 +00:00

LazyCallGraphTest.cpp

[LCG] Switch one of the update methods for the LazyCallGraph to support

2017-08-09 09:05:27 +00:00

LoopInfoTest.cpp

[LoopInfo] Add helper methods to compute two useful orderings of the

2017-01-20 02:41:20 +00:00

MemoryBuiltinsTest.cpp

Don't consider allocsize functions to be allocation functions.

2016-12-23 01:18:09 +00:00

MemorySSA.cpp

[mssa] Fix case when there is no definition in a block prior to an inserted use.

2017-06-07 16:46:53 +00:00

OrderedBasicBlockTest.cpp

[OrderedBasicBlock] Return false for comesBefore(A, A)

2017-06-02 13:10:31 +00:00

ProfileSummaryInfoTest.cpp

Do not want to use BFI to get profile count for sample pgo

2017-08-03 17:11:41 +00:00

ScalarEvolutionTest.cpp

[SCEV] Ensure ScalarEvolution::createAddRecFromPHIWithCastsImpl properly handles out of range truncations of the start and accum values

2017-09-05 19:54:03 +00:00

TargetLibraryInfoTest.cpp

Revert "Add pthread_self function prototype and make it speculatable."

2017-05-21 00:37:55 +00:00

TBAATest.cpp

Re-sort #include lines for unittests. This uses a slightly modified

2017-06-06 11:06:56 +00:00

UnrollAnalyzer.cpp

Re-sort #include lines for unittests. This uses a slightly modified

2017-06-06 11:06:56 +00:00

ValueTrackingTest.cpp

[ValueTracking] Avoid undefined behavior in unittest by not making a named ArrayRef from a std::initializer_list

2017-04-14 17:59:19 +00:00