Do not track subregister liveness when it brings no benefits
authorMatthias Braun <matze@braunis.de>
Thu, 19 Mar 2015 00:21:58 +0000 (00:21 +0000)
committerMatthias Braun <matze@braunis.de>
Thu, 19 Mar 2015 00:21:58 +0000 (00:21 +0000)
commita25e13aaf1364b899656d43a16a4f768135efc1f
treede074ec880448599512590c0c3df73e2b4a0e2bc
parenta8f2f1da999b7ef1e5e16ec539164106018cb431
Do not track subregister liveness when it brings no benefits

Some subregisters are only to indicate different access sizes, while not
providing any way to actually divide the register up into multiple
disjunct parts. Avoid tracking subregister liveness in these cases as it
is not beneficial.

Differential Revision: http://reviews.llvm.org/D8429

llvm-svn: 232695
llvm/include/llvm/CodeGen/MachineRegisterInfo.h
llvm/include/llvm/Target/TargetRegisterInfo.h
llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
llvm/lib/CodeGen/LiveRangeCalc.cpp
llvm/lib/CodeGen/LiveRangeCalc.h
llvm/lib/CodeGen/MachineVerifier.cpp
llvm/lib/CodeGen/RegisterCoalescer.cpp
llvm/lib/CodeGen/VirtRegMap.cpp
llvm/utils/TableGen/CodeGenRegisters.cpp
llvm/utils/TableGen/CodeGenRegisters.h
llvm/utils/TableGen/RegisterInfoEmitter.cpp