This is a new algorithm that finds sets of register units that can be
used to model registers pressure. This handles arbitrary, overlapping
register classes. Each register class is associated with a (small)
list of pressure sets. These are the dimensions of pressure affected
by the register class's liveness.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154374 91177308-0d34-0410-b5e6-96231b3b80d8
This also avoids emitting the information twice, which led to code bloat. On i386-linux-Release+Asserts
with all targets built this change shaves a whopping 1.3 MB off clang. The number is probably exaggerated
by recent inliner changes but the methods were already enormous with the old inline cost computation.
The DWARF reg -> LLVM reg mapping doesn't seem to have holes in it, so it could be a simple lookup table.
I didn't implement that optimization yet to avoid potentially changing functionality.
There is still some duplication both in tablegen and the generated code that should be cleaned up eventually.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153837 91177308-0d34-0410-b5e6-96231b3b80d8
to MCRegisterInfo. Also initialize the mapping at construction time.
This patch eliminate TargetRegisterInfo from TargetAsmInfo. It's another step
towards fixing the layering violation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135424 91177308-0d34-0410-b5e6-96231b3b80d8
target machine from those that are only needed by codegen. The goal is to
sink the essential target description into MC layer so we can start building
MC based tools without needing to link in the entire codegen.
First step is to refactor TargetRegisterInfo. This patch added a base class
MCRegisterInfo which TargetRegisterInfo is derived from. Changed TableGen to
separate register description from the rest of the stuff.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133782 91177308-0d34-0410-b5e6-96231b3b80d8