[AArch64]Select wide immediate offset into [Base+XReg] addressing mode
e.g Currently we'll generate following instructions if the immediate is too wide:
    MOV  X0, WideImmediate
    ADD  X1, BaseReg, X0
    LDR  X2, [X1, 0]

    Using [Base+XReg] addressing mode can save one ADD as following:
    MOV  X0, WideImmediate
    LDR  X2, [BaseReg, X0]

    Differential Revision: http://reviews.llvm.org/D5477


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219665 91177308-0d34-0410-b5e6-96231b3b80d8
Access the subtarget off of the MachineFunction via the DAG
scheduler or via the SelectionDAG if available. Otherwise
grab the subtarget off of the MachineFunction by going up
the parent chain.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219666 91177308-0d34-0410-b5e6-96231b3b80d8
Add lld to the parallel set of directories since it doesn't depend
on any of the other tools directories.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219667 91177308-0d34-0410-b5e6-96231b3b80d8
Access subtarget specific variables off of the MachineFunction's
cached subtarget and not the TargetMachine.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219668 91177308-0d34-0410-b5e6-96231b3b80d8
Instead of the TargetMachine cache the MachineFunction
and TargetRegisterInfo in the peephole optimizer. This
makes it easier to grab subtarget dependent variables off
of the MachineFunction rather than the TargetMachine.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219669 91177308-0d34-0410-b5e6-96231b3b80d8
Grab the subtarget and subtarget dependent variables off of
MachineFunction rather than TargetMachine.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219670 91177308-0d34-0410-b5e6-96231b3b80d8
Grab the subtarget and subtarget dependent variables off of
MachineFunction rather than TargetMachine.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219671 91177308-0d34-0410-b5e6-96231b3b80d8
Remove unnecessary TargetMachine.h includes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219672 91177308-0d34-0410-b5e6-96231b3b80d8