llvm-6502/test/Analysis
Silviu Baranga 8bde857088 [LAA] Merge memchecks for accesses separated by a constant offset
Summary:
Often filter-like loops will do memory accesses that are
separated by constant offsets. In these cases it is
common that we will exceed the threshold for the
allowable number of checks.

However, it should be possible to merge such checks,
sice a check of any interval againt two other intervals separated
by a constant offset (a,b), (a+c, b+c) will be equivalent with
a check againt (a, b+c), as long as (a,b) and (a+c, b+c) overlap.
Assuming the loop will be executed for a sufficient number of
iterations, this will be true. If not true, checking against
(a, b+c) is still safe (although not equivalent).

As long as there are no dependencies between two accesses,
we can merge their checks into a single one. We use this
technique to construct groups of accesses, and then check
the intervals associated with the groups instead of
checking the accesses directly.

Reviewers: anemet

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D10386

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241673 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-08 09:16:33 +00:00
..
AssumptionCache
BasicAA Revert r236894 "[BasicAA] Fix zext & sext handling" 2015-05-22 01:27:37 +00:00
BlockFrequencyInfo Add documentation for new backedge mass propagation in irregular loops. 2015-06-17 16:28:22 +00:00
BranchProbabilityInfo
CallGraph [CallGraph] Given -print-callgraph a stable printing order. 2015-06-19 23:20:31 +00:00
CFLAliasAnalysis
CostModel [X86][SSE] Vectorized i64 uniform constant SRA shifts 2015-07-06 22:35:19 +00:00
Delinearization
DependenceAnalysis [DependenceAnalysis] Extend unifySubscriptType for handling coupled subscript groups. 2015-05-29 16:58:08 +00:00
DivergenceAnalysis/NVPTX
Dominators Move the personality function from LandingPadInst to Function 2015-06-17 20:52:32 +00:00
GlobalsModRef
LazyCallGraph [LazyCallGraph] Port test case from r240039 to LCG. 2015-07-02 02:03:58 +00:00
Lint Move the personality function from LandingPadInst to Function 2015-06-17 20:52:32 +00:00
LoopAccessAnalysis [LAA] Merge memchecks for accesses separated by a constant offset 2015-07-08 09:16:33 +00:00
LoopInfo
MemoryDependenceAnalysis
PostDominators
RegionInfo
ScalarEvolution
ScopedNoAliasAA [Testsuite] Renumber metadata in ScopedNoAliasAA test to match CHECK lines 2015-05-11 09:10:14 +00:00
TypeBasedAliasAnalysis
ValueTracking [ValueTracking] do not overwrite analysis results already computed 2015-06-15 05:46:29 +00:00