[PATCH] D19337: [Tail duplication] Handle source registers with subregisters

[Krzysztof Parzyszek via llvm-commits]

kparzysz marked 3 inline comments as done.

================
Comment at: lib/CodeGen/TailDuplicator.cpp:392
@@ +391,3 @@
+                    TII->get(TargetOpcode::COPY), NewReg)
+                .addReg(Reg);
+            LocalVRMap.erase(VI);
----------------
qcolombet wrote:
> We need to read from Reg:subReg if Reg has a sub reg.
Actually, we need to leave the sub-reg alone.  NewReg will be inserted into the LocalVRMap as a replacement for Reg.  Since there is no Reg anymore (it should be the value taken from VI.Reg:VI:SubReg), the COPY should use the VI.* values instead of Reg.


Repository:
  rL LLVM

http://reviews.llvm.org/D19337