tree d0297a19698b736a25b4e39180d3d61492e962ff
parent fa9dbc4f439a28223aee14b5dd97cd6fbd35dc16
author Sean Fertile <sfertile@ca.ibm.com> 1539709981 +0000
committer Sean Fertile <sfertile@ca.ibm.com> 1539709981 +0000

Reland "[PPC64] Add split - stack support."

Recommitting https://reviews.llvm.org/rL344544 after fixing undefined behavior
from left-shifting a negative value. Original commit message:

This support is slightly different then the X86_64 implementation in that calls
to __morestack don't need to get rewritten to calls to __moresatck_non_split
when a split-stack caller calls a non-split-stack callee. Instead the size of
the stack frame requested by the caller is adjusted prior to the call to
__morestack. The size the stack-frame will be adjusted by is tune-able through a
new --split-stack-adjust-size option.

git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@344622 91177308-0d34-0410-b5e6-96231b3b80d8