[all-commits] [llvm/llvm-project] a9ad65: [PowerPC] Change default for unaligned FP access f...

[Nemanja Ivanovic via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: a9ad65a2b34f9cbcd207114caa862ef2dc4553c8
      https://github.com/llvm/llvm-project/commit/a9ad65a2b34f9cbcd207114caa862ef2dc4553c8
  Author: Nemanja Ivanovic <nemanja.i.ibm at gmail.com>
  Date:   2019-12-28 (Sat, 28 Dec 2019)

  Changed paths:
    M llvm/lib/Target/PowerPC/PPC.td
    M llvm/lib/Target/PowerPC/PPCISelLowering.cpp
    M llvm/lib/Target/PowerPC/PPCSubtarget.h
    M llvm/test/CodeGen/PowerPC/2007-09-08-unaligned.ll
    A llvm/test/CodeGen/PowerPC/unaligned-floats.ll

  Log Message:
  -----------
  [PowerPC] Change default for unaligned FP access for older subtargets

This is a fix for https://bugs.llvm.org/show_bug.cgi?id=40554

Some CPU's trap to the kernel on unaligned floating point access and there are
kernels that do not handle the interrupt. The program then fails with a SIGBUS
according to the PR. This just switches the default for unaligned access to only
allow it on recent server CPUs that are known to allow this.

Differential revision: https://reviews.llvm.org/D71954