Add DemandedElts support inside the TRUNCATE analysis.
REAPPLIED - this was reverted by @hans at rGa51226057fc3 due to an issue with vector shift amount types, which was fixed in rG935bacd3a724 and an additional test case added at rG0ca81b90d19d
Differential Revision: https://reviews.llvm.org/D56387
It caused "Vector shift amounts must be in the same as their first arg"
asserts in Chromium builds. See the code review for repro instructions.
> Add DemandedElts support inside the TRUNCATE analysis.
>
> Differential Revision: https://reviews.llvm.org/D56387
This reverts commit cad4275d69.
In LowerMUL, the chain information is not preserved for the new
created Load SDNode.
For example, if a Store alias with one of the operand of Mul.
The Load for that operand need to be scheduled before the Store.
The dependence is recorded in the chain of Store, in TokenFactor.
However, when lowering MUL, the SDNodes for the new Loads for
VMULL are not updated in the TokenFactor for the Store. Thus the
chain is not preserved for the lowered VMULL.
llvm-svn: 299701
Simon Pilgrim