add basic PPC register-pressure feedback; adjust the vaarg test to match the new register-allocation pattern

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145065 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCInstrInfo.cpp b/lib/Target/PowerPC/PPCInstrInfo.cpp
index 644b20c..b9a6297 100644
--- a/lib/Target/PowerPC/PPCInstrInfo.cpp
+++ b/lib/Target/PowerPC/PPCInstrInfo.cpp
@@ -56,11 +56,8 @@
 
   unsigned Directive = TM->getSubtarget<PPCSubtarget>().getDarwinDirective();
   if (Directive == PPC::DIR_440) {
-    // Disable the hazard recognizer for now, as it doesn't support
-    // bottom-up scheduling.
-    //const InstrItineraryData *II = TM->getInstrItineraryData();
-    //return new PPCHazardRecognizer440(II, DAG);
-    return new ScheduleHazardRecognizer();
+    const InstrItineraryData *II = TM->getInstrItineraryData();
+    return new PPCHazardRecognizer440(II, DAG);
   }
   else {
     // Disable the hazard recognizer for now, as it doesn't support