[all-commits] [llvm/llvm-project] fd0557: [WebAssembly] More convert_low and promote_low cod...

[Thomas Lively via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: fd0557dbf13198ddd6a17bd120a7b2bb97bfbd0a
      https://github.com/llvm/llvm-project/commit/fd0557dbf13198ddd6a17bd120a7b2bb97bfbd0a
  Author: Thomas Lively <tlively at google.com>
  Date:   2021-08-19 (Thu, 19 Aug 2021)

  Changed paths:
    M llvm/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp
    M llvm/test/CodeGen/WebAssembly/simd-conversions.ll

  Log Message:
  -----------
  [WebAssembly] More convert_low and promote_low codegen

The convert_low and promote_low instructions can widen the lower two lanes of a
four-lane vector, but we were previously scalarizing patterns that widened lanes
besides the low two lanes. The commit adds a shuffle to move the widened lanes
into the low lane positions so the convert_low and promote_low instructions can
be used instead of scalarizing.

Depends on D108266.

Differential Revision: https://reviews.llvm.org/D108341