Let callers decide the sub-register index on the def operand of rematerialized instructions.
Avoid remat'ing instructions whose def have sub-register indices for now. It's just really really hard to get all the cases right.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75900 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/TwoAddressInstructionPass.cpp b/lib/CodeGen/TwoAddressInstructionPass.cpp
index b67f84b..83468d9 100644
--- a/lib/CodeGen/TwoAddressInstructionPass.cpp
+++ b/lib/CodeGen/TwoAddressInstructionPass.cpp
@@ -798,6 +798,7 @@
           //     a = a op c
           unsigned regA = mi->getOperand(ti).getReg();
           unsigned regB = mi->getOperand(si).getReg();
+          unsigned regASubIdx = mi->getOperand(ti).getSubReg();
 
           assert(TargetRegisterInfo::isVirtualRegister(regB) &&
                  "cannot update physical register live information");
@@ -946,7 +947,7 @@
               DefMI->isSafeToReMat(TII, regB) &&
               isProfitableToReMat(regB, rc, mi, DefMI, mbbi, Dist)){
             DEBUG(cerr << "2addr: REMATTING : " << *DefMI << "\n");
-            TII->reMaterialize(*mbbi, mi, regA, DefMI);
+            TII->reMaterialize(*mbbi, mi, regA, regASubIdx, DefMI);
             ReMatRegs.set(regB);
             ++NumReMats;
           } else {