AMDGPU: Cache information about register pressure sets

We can statically decide whether or not a register pressure set is for
SGPRs or VGPRs, so we don't need to re-compute this information in
SIRegisterInfo::getRegPressureSetLimit().

Differential Revision: http://reviews.llvm.org/D14805

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@264126 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed