commit ce23689b40c282c4f851d485beb6187e9c51e13a
author Simon Pilgrim <llvm-dev@redking.me.uk> Mon Mar 25 15:53:55 2019 +0000
committer Simon Pilgrim <llvm-dev@redking.me.uk> Mon Mar 25 15:53:55 2019 +0000
tree 129b800221a1c2949009d66d25f43e92d6f71f8a
parent 8ee86696d74ac7955b3998bb4d5362f3ac8e3134

[SLPVectorizer] reorderInputsAccordingToOpcode - remove non-Instruction canonicalization

Remove attempts to commute non-Instructions to the LHS - the codegen changes appear to rely on chance more than anything else and also have a tendency to fight existing instcombine canonicalization which moves constants to the RHS of commutable binary ops.

This is prep work towards:
(a) reusing reorderInputsAccordingToOpcode for alt-shuffles and removing the similar reorderAltShuffleOperands
(b) improving reordering to optimized cases with commutable and non-commutable instructions to still find splat/consecutive ops.

Differential Revision: https://reviews.llvm.org/D59738

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356913 91177308-0d34-0410-b5e6-96231b3b80d8