[llvm-commits] [llvm] r150553 - /llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp

[Lang Hames]

Author: lhames
Date: Tue Feb 14 19:31:10 2012
New Revision: 150553

URL: http://llvm.org/viewvc/llvm-project?rev=150553&view=rev
Log:
Don't emit live ranges for physregs live-ins that are dead.

Modified:
    llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp

Modified: llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp?rev=150553&r1=150552&r2=150553&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp (original)
+++ llvm/trunk/lib/CodeGen/LiveIntervalAnalysis.cpp Tue Feb 14 19:31:10 2012
@@ -529,9 +529,10 @@
   if (!SeenDefUse) {
     if (isAllocatable(interval.reg) || isReserved(interval.reg)) {
       // This must be an entry block or landing pad - we asserted so on entry
-      // to the function. For these blocks the interval is dead on entry.
+      // to the function. For these blocks the interval is dead on entry, so
+      // we won't emit a live-range for it.
       DEBUG(dbgs() << " dead");
-      end = start.getDeadSlot();
+      return;
     } else {
       assert(isRegLiveOutOf(MBB, interval.reg) &&
              "Live in reg untouched in block should be be live through.");