These passes are optimizations, and should be disabled when not
optimizing.
Also create an MCCodeGenInfo so the opt level is correctly plumbed to
the backend pass manager.
Also remove the command line flag for disabling register coloring;
running llc with -O0 should now be useful for debugging, so it's not
necessary.
Differential Revision: http://reviews.llvm.org/D17327
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@261176 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of trying to move ARGUMENT instructions back up to the top after
they've been scheduled or sunk down, use a fake physical register to
create a liveness constraint that prevents ARGUMENT instructions from
moving down in the first place. This is still not entirely ideal, however
it is more robust than letting them move and moving them back.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254084 91177308-0d34-0410-b5e6-96231b3b80d8
coloring pass. Turn the logic into "look for an insert point and
then move things past the insert point".
No functional change intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253626 91177308-0d34-0410-b5e6-96231b3b80d8
This also takes the push/pop syntax another step forward, introducing stack
slot numbers to make it easier to see how expressions are connected. For
example, the value pushed in $push7 is popped in $pop7.
And, this begins an experiment with making get_local and set_local implicit
when an operation directly uses or defines a register. This greatly reduces
clutter. If this experiment succeeds, it may make sense to do this for
const instructions as well.
And, this introduces more special code for ARGUMENTS; hopefully this code
will soon be obviated by proper support for live-in virtual registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253465 91177308-0d34-0410-b5e6-96231b3b80d8
