AMDGPU: Make getSubRegFromChannel a static member of AMDGPURegisterInfo

Summary:
This makes is possible to have R600RegisterInfo and SIRegisterInfo
not inherit from AMDGPURegisterInfo.

Reviewers: arsenm, nhaehnle

Reviewed By: arsenm

Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, llvm-commits, t-tye

Differential Revision: https://reviews.llvm.org/D46280

llvm-svn: 331490
diff --git a/llvm/lib/Target/AMDGPU/R600ControlFlowFinalizer.cpp b/llvm/lib/Target/AMDGPU/R600ControlFlowFinalizer.cpp
index 0e788df..0fbc254 100644
--- a/llvm/lib/Target/AMDGPU/R600ControlFlowFinalizer.cpp
+++ b/llvm/lib/Target/AMDGPU/R600ControlFlowFinalizer.cpp
@@ -308,7 +308,7 @@
           DstMI = Reg;
         else
           DstMI = TRI->getMatchingSuperReg(Reg,
-              TRI->getSubRegFromChannel(TRI->getHWRegChan(Reg)),
+              AMDGPURegisterInfo::getSubRegFromChannel(TRI->getHWRegChan(Reg)),
               &AMDGPU::R600_Reg128RegClass);
       }
       if (MO.isUse()) {
@@ -317,7 +317,7 @@
           SrcMI = Reg;
         else
           SrcMI = TRI->getMatchingSuperReg(Reg,
-              TRI->getSubRegFromChannel(TRI->getHWRegChan(Reg)),
+              AMDGPURegisterInfo::getSubRegFromChannel(TRI->getHWRegChan(Reg)),
               &AMDGPU::R600_Reg128RegClass);
       }
     }