Try harder to get a consistent floating point results.

This just extends the existing hack. It should be enough to get a reproducible bootstrap
on 32 bits.

I will open a bug to track getting a real fix for this.

llvm-svn: 196462

llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

@@ -2351,7 +2351,7 @@ bool SelectionDAGBuilder::handleBTSplitSwitchCase(CaseRec& CR,
     volatile double RDensity =
       (double)RSize.roundToDouble() /
                            (Last - RBegin + 1ULL).roundToDouble();
-    double Metric = Range.logBase2()*(LDensity+RDensity);
+    volatile double Metric = Range.logBase2()*(LDensity+RDensity);
     // Should always split in some non-trivial place
     DEBUG(dbgs() <<"=>Step\n"
                  << "LEnd: " << LEnd << ", RBegin: " << RBegin << '\n'