Dorit Nuzman 3ce8b664b3 [LV] Support efficient vectorization of an induction with redundant casts ... D30041 extended SCEVPredicateRewriter to improve handling of Phi nodes whose update chain involves casts; PSCEV can now build an AddRecurrence for some forms of such phi nodes, under the proper runtime overflow test. This means that we can identify such phi nodes as an induction, and the loop-vectorizer can now vectorize such inductions, however inefficiently. The vectorizer doesn't know that it can ignore the casts, and so it vectorizes them. This patch records the casts in the InductionDescriptor, so that they could be marked to be ignored for cost calculation (we use VecValuesToIgnore for that) and ignored for vectorization/widening/scalarization (i.e. treated as TriviallyDead). In addition to marking all these casts to be ignored, we also need to make sure that each cast is mapped to the right vector value in the vector loop body (be it a widened, vectorized, or scalarized induction). So whenever an induction phi is mapped to a vector value (during vectorization/widening/ scalarization), we also map the respective cast instruction (if exists) to that vector value. (If the phi-update sequence of an induction involves more than one cast, then the above mapping to vector value is relevant only for the last cast of the sequence as we allow only the "last cast" to be used outside the induction update chain itself). This is the last step in addressing PR30654. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320672 91177308-0d34-0410-b5e6-96231b3b80d8		2017-12-14 07:56:31 +00:00
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Coroutines	[coro] Make Spill a proper struct instead of deriving from pair.	2017-10-31 19:22:55 +00:00
Hello
InstCombine	Remove redundant includes from lib/Transforms.	2017-12-13 21:31:01 +00:00
Instrumentation	Remove redundant includes from lib/Transforms.	2017-12-13 21:31:01 +00:00
IPO	Remove redundant includes from lib/Transforms.	2017-12-13 21:31:01 +00:00
ObjCARC	Remove redundant includes from lib/Transforms.	2017-12-13 21:31:01 +00:00
Scalar	[EarlyCSE] recognize swapped variants of abs/nabs as equivalent	2017-12-13 22:57:35 +00:00
Utils	[LV] Support efficient vectorization of an induction with redundant casts	2017-12-14 07:56:31 +00:00
Vectorize	[LV] Support efficient vectorization of an induction with redundant casts	2017-12-14 07:56:31 +00:00
CMakeLists.txt
LLVMBuild.txt