[all-commits] [llvm/llvm-project] 5b7e27: [ARM][CGP] Fix scalar condition selects for MVE

[David Green via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 5b7e27a4db95a07cc140e3980a49a1ee3fb2052c
      https://github.com/llvm/llvm-project/commit/5b7e27a4db95a07cc140e3980a49a1ee3fb2052c
  Author: David Green <david.green at arm.com>
  Date:   2020-08-25 (Tue, 25 Aug 2020)

  Changed paths:
    M llvm/lib/CodeGen/CodeGenPrepare.cpp
    A llvm/test/CodeGen/Thumb2/mve-selectcc.ll

  Log Message:
  -----------
  [ARM][CGP] Fix scalar condition selects for MVE

The arm backend does not handle select/select_cc on vectors with scalar
conditions, preferring to expand them in codegenprepare instead. This
usually works except when optimizing for size, where the optsize check
would end up overruling the backend isSelectSupported check.

We could handle the selects in ISel too, but this seems like smaller
code than trying to splat the condition to all lanes.

Differential Revision: https://reviews.llvm.org/D86433