[PATCH] [PowerPC] Change liveness testing in VSX FMA mutation pass

[hfinkel at anl.gov]

LGTM.

================
Comment at: lib/Target/PowerPC/PPCInstrInfo.cpp:1691
@@ -1689,3 +1690,3 @@
         // logic below and I suspect it will not occur in any relevant
-        // situations.
-        bool OtherUsers = false;
+        // situations.  Additionally, check for whether the copy source is
+        // killed prior to the fma.  In order to replace the addend here with
----------------
check for whether -> check whether

================
Comment at: lib/Target/PowerPC/PPCInstrInfo.cpp:1724
@@ -1723,3 +1731,1 @@
-          continue;
-
         // Transform: (O2 * O3) + O1 -> (O2 * O1) + O3.
----------------
Because I'm so trusting... please don't delete this; instead turn it into an assert that checks this condition (for virtual registers).

http://reviews.llvm.org/D5847