Sanjay Patel 113cac3b15 [SelectionDAG][x86] turn insertelement into undef with variable index into splat ... I noticed this along with the patterns in D51125, but when the index is variable, we don't convert insertelement into a build_vector. For x86, that means these get expanded at legalization time into the loading/spilling code that we see in the tests. I think it's always better to avoid going to memory on these, and we get the optimal 'broadcast' if it's available. I suspect other targets may want to look at enabling the hook. AArch64 and AMDGPU have regression tests that would be affected (although I did not check what would happen in those cases). In the most basic cases shown here, AArch64 would probably do much better with a splat. Differential Revision: https://reviews.llvm.org/D51186 llvm-svn: 340705		2018-08-26 18:20:41 +00:00
..
llvm	[SelectionDAG][x86] turn insertelement into undef with variable index into splat	2018-08-26 18:20:41 +00:00
llvm-c	[AArch64] Add Tiny Code Model for AArch64	2018-08-22 11:31:39 +00:00