Merging r353082:

Merging r353082:
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r353082 | meinersbur | 2019-02-04 20:55:59 +0100 (Mon, 04 Feb 2019) | 10 lines

[WarnMissedTransforms] Do not warn about already vectorized loops.

LoopVectorize adds llvm.loop.isvectorized, but leaves
llvm.loop.vectorize.enable. Do not consider such a loop for user-forced
vectorization since vectorization already happened -- by prioritizing
llvm.loop.isvectorized except for TM_SuppressedByUser.

Fixes http://llvm.org/PR40546

Differential Revision: https://reviews.llvm.org/D57542
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_80@353166 91177308-0d34-0410-b5e6-96231b3b80d8