Eli Friedman fc70228004 [ARM] Check correct instructions for load/store rescheduling.
This code starts from the high end of the sorted vector of offsets, and
works backwards: it tries to find contiguous offsets, process them, then
pops them from the end of the vector. Most of the code agrees with this
order of processing, but one loop doesn't: it instead processes elements
from the low end of the vector (which are nodes with unrelated offsets).
Fix that loop to process the correct elements.
    
This has a few implications. One, we don't incorrectly return early when
processing multiple groups of offsets in the same block (which allows
rescheduling prera-ldst-insertpt.mir). Two, we pick the correct insert
point for loads, so they're correctly sorted (which affects the
scheduling of vldm-liveness.ll). I think it might also impact some of
the heuristics slightly.
    
Differential Revision: https://reviews.llvm.org/D30368



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296701 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-01 22:56:20 +00:00
..