[llvm-commits] [llvm] r54174 - /llvm/trunk/lib/CodeGen/StrongPHIElimination.cpp

[Owen Anderson]

Author: resistor
Date: Tue Jul 29 16:17:08 2008
New Revision: 54174

URL: http://llvm.org/viewvc/llvm-project?rev=54174&view=rev
Log:
When merging a PHI operand's live interval into the PHI's live interval, we need to merge over all liveranges in
the operand's interval that share the relevant value number, not just the range that immediately precedes the PHI.

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

Modified: llvm/trunk/lib/CodeGen/StrongPHIElimination.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/StrongPHIElimination.cpp?rev=54174&r1=54173&r2=54174&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/StrongPHIElimination.cpp (original)
+++ llvm/trunk/lib/CodeGen/StrongPHIElimination.cpp Tue Jul 29 16:17:08 2008
@@ -786,21 +786,29 @@
   LiveInterval& RHS = LI.getOrCreateInterval(secondary);
   
   LI.computeNumbering();
-  
   const LiveRange* RangeMergingIn =
                    RHS.getLiveRangeContaining(LI.getMBBEndIdx(pred));
+  VNInfo* RHSVN = RangeMergingIn->valno;
   VNInfo* NewVN = LHS.getNextValue(RangeMergingIn->valno->def,
                                    RangeMergingIn->valno->copy,
                                    LI.getVNInfoAllocator());
-  NewVN->hasPHIKill = true;
-  LiveRange NewRange(RangeMergingIn->start, RangeMergingIn->end, NewVN);
+                                   
+  for (LiveInterval::iterator RI = RHS.begin(), RE = RHS.end();
+       RI != RE; )
+    if (RI->valno == RHSVN) {
+      NewVN->hasPHIKill = true;
+      LiveRange NewRange(RI->start, RI->end, NewVN);
+      LHS.addRange(NewRange);
+      
+      unsigned start = RI->start;
+      unsigned end = RI->end;
+      ++RI;
+      RHS.removeRange(start, end, true);
+    } else
+      ++RI;
   
-  if (RHS.containsOneValue())
+  if (RHS.begin() == RHS.end())
     LI.removeInterval(RHS.reg);
-  else
-    RHS.removeRange(RangeMergingIn->start, RangeMergingIn->end, true);
-  
-  LHS.addRange(NewRange);
 }
 
 bool StrongPHIElimination::runOnMachineFunction(MachineFunction &Fn) {