[all-commits] [llvm/llvm-project] 7edc7f: [CodeGen] Fix SimplifyDemandedBits for scalable ve...

[david-arm via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 7edc7f6edbcb5be439886c271a71df43b3f0a8e3
      https://github.com/llvm/llvm-project/commit/7edc7f6edbcb5be439886c271a71df43b3f0a8e3
  Author: David Sherwood <david.sherwood at arm.com>
  Date:   2020-06-19 (Fri, 19 Jun 2020)

  Changed paths:
    M llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
    M llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
    M llvm/test/CodeGen/AArch64/sve-int-arith.ll
    M llvm/test/CodeGen/AArch64/sve-int-imm.ll
    M llvm/test/CodeGen/AArch64/sve-int-log-imm.ll
    M llvm/test/CodeGen/AArch64/sve-int-log.ll
    M llvm/test/CodeGen/AArch64/sve-intrinsics-perm-select.ll
    M llvm/test/CodeGen/AArch64/sve-intrinsics-reinterpret.ll
    M llvm/unittests/CodeGen/AArch64SelectionDAGTest.cpp

  Log Message:
  -----------
  [CodeGen] Fix SimplifyDemandedBits for scalable vectors

For now I have changed SimplifyDemandedBits and it's various callers
to assume we know nothing for scalable vectors and to ignore the
demanded bits completely. I have also done something similar for
SimplifyDemandedVectorElts. These changes fix up lots of warnings
due to calls to EVT::getVectorNumElements() for types with scalable
vectors. These functions are all used for optimisations, rather than
functional requirements. In future we can revisit this code if
there is a need to improve code quality for SVE.

Differential Revision: https://reviews.llvm.org/D80537