Revert "[Thumb/Thumb2] Added restrictions on PC, LR, SP in the register list for PUSH/POP/LDM/STM. <Differential Revision: http://reviews.llvm.org/D6090>"

This reverts commit r223356.

It was failing check-all (MC/ARM/thumb.s in particular).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223363 91177308-0d34-0410-b5e6-96231b3b80d8
Revert r223347 which has caused crashes on bootstrap bots.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223364 91177308-0d34-0410-b5e6-96231b3b80d8
Use size_type in the interface exposed by SmallVector.

This matches std::vector and should avoid unnecessary masking to 32 bits
when calling them on o 64 bits system.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223365 91177308-0d34-0410-b5e6-96231b3b80d8
Fix a minor regression introduced in r223113

r223113 added support for ARM modified immediate assembly syntax. That patch
has broken support for immediate expressions, as in:
    add r0, #(4 * 4)
It wasn't caught because we don't have any tests for this feature. This patch
fixes this regression and adds test cases.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223366 91177308-0d34-0410-b5e6-96231b3b80d8