R600/SI: Legalize operands after changing dst reg in FixSGPRCopies

Otherwise we may not legalize some illegal REG_SEQUENCE instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206497 91177308-0d34-0410-b5e6-96231b3b80d8
R600/SI: Teach SIInstrInfo::moveToVALU() how to handle PHI instructions

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206498 91177308-0d34-0410-b5e6-96231b3b80d8
R600/SI: Change default register class for i32 to SReg_32

SIFixSGPRCopies is smart enough to handle this now.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206499 91177308-0d34-0410-b5e6-96231b3b80d8
R600/SI: Stop using i128 as the resource descriptor type

Having i128 as a legal type complicates the legalization phase.  v4i32
is already a legal type, so we will use that instead.

This fixes several piglit tests.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206500 91177308-0d34-0410-b5e6-96231b3b80d8
R600: Add comment clariying use of sext for result of MUL_U24

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206501 91177308-0d34-0410-b5e6-96231b3b80d8