Commit Graph

2 Commits

Author SHA1 Message Date
Matt Arsenault 1022c0dfde AMDGPU: Decompose all values to 32-bit pieces for calling conventions
This is the more natural lowering, and presents more opportunities to
reduce 64-bit ops to 32-bit.

This should also help avoid issues graphics shaders have had with
64-bit values, and simplify argument lowering in globalisel.

llvm-svn: 366578
2019-07-19 13:57:44 +00:00
Michael Liao 9c70c574b4 [SelectionDAG] Enhance the simplification of `copyto` from `implicit-def`.
Summary:
- The current implementation simplifies the case where the source of
  `copyto` is `implicit-def`ed. However, it only works when that
  `implicit-def` is single-used since it detects that from
  `implicit-def` and cannot determine which destination vreg should be
  used if there are multiple uses.
- This patch changes that detection when `copyto` is being emitted. If
  that `copyto`'s source is defined from `implicit-def`, it simplifies
  it. Hence, it works even that `implicit-def` is multi-used.
- Except it simplifies the internal IR, it won't improve the quality of
  code generation. However, it helps to detect 'implicit-def` in a
  straight-forward manner in some passes, such as `si-i1-copies`. A test
  case is added.

Reviewers: sunfish, nhaehnle

Subscribers: jvesely, hiraditya, asbirlea, llvm-commits, yaxunl

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62342

llvm-svn: 361777
2019-05-27 18:26:29 +00:00