Move the stdu instruction in the prologue and epilogue.
This should provide a small performance boost in functions that are able to do
this. I've kept this change rather conservative at the moment and functions
with frame pointers or base pointers will not try to move the stack pointer
update.
Differential Revision: https://reviews.llvm.org/D42590
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@355085 91177308-0d34-0410-b5e6-96231b3b80d8
Added four test files to check the existing behaviour of prologue
and epilogue code generation. This patch was done as a setup for
the upcoming patch listed on Phabricator that will change how the
prologue and epilogue work.
The upcoming patch is: https://reviews.llvm.org/D42590
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353994 91177308-0d34-0410-b5e6-96231b3b80d8