1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-24 03:33:20 +01:00
llvm-mirror/test/Analysis
Ahmed Bougacha 6b2a6f7419 [BasicAA] Try to disambiguate GEPs through arrays of structs into
different fields.

We can show that two GEPs off of the same (possibly multidimensional)
array of structs, into different fields, can't alias.  Quoting:

For two GEPOperators GEP1 and GEP2, if we find that:
- both GEPs begin indexing from the exact same pointer;
- the last indices in both GEPs are constants, indexing into a struct;
- said indices are different, hence,the pointed-to fields are different;
- and both GEPs only index through arrays prior to that;

this lets us determine that the struct that GEP1 indexes into and the
struct that GEP2 indexes into must either precisely overlap or be
completely disjoint.  Because they cannot partially overlap, indexing
into different non-overlapping fields of the struct will never alias.

The other BasicAA::aliasGEP rules worked in some cases, but not all
(for example, the i32x3 struct in the testcase).
We can add this simple ad-hoc rule to complement them.

rdar://19717375
Differential Revision: http://reviews.llvm.org/D7453

llvm-svn: 228498
2015-02-07 17:04:29 +00:00
..
AssumptionCache [PM] Actually add the new pass manager support for the assumption cache. 2015-01-22 21:53:09 +00:00
BasicAA [BasicAA] Try to disambiguate GEPs through arrays of structs into 2015-02-07 17:04:29 +00:00
BlockFrequencyInfo
BranchProbabilityInfo
CallGraph
CFLAliasAnalysis Fix incorrect partial aliasing 2015-01-26 17:31:17 +00:00
CostModel [PM] Change the core design of the TTI analysis to use a polymorphic 2015-01-31 03:43:40 +00:00
Delinearization
DependenceAnalysis
Dominators
GlobalsModRef
LazyCallGraph
Lint
LoopInfo [PM] Port LoopInfo to the new pass manager, adding both a LoopAnalysis 2015-01-20 10:58:50 +00:00
MemoryDependenceAnalysis
PostDominators
RegionInfo
ScalarEvolution Make ScalarEvolution less aggressive with respect to no-wrap flags. 2015-01-22 00:48:47 +00:00
ScopedNoAliasAA
TypeBasedAliasAnalysis
ValueTracking Introduce print-memderefs to test isDereferenceablePointer 2015-02-06 01:46:42 +00:00