From: Owen Anderson <resistor@mac.com>
Date: Tue, 29 Jul 2008 21:17:08 +0000 (+0000)
Subject: When merging a PHI operand's live interval into the PHI's live interval, we need... 
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=83ea1f8e19dc1fae54a3e40689ad0a76a8ff3992;p=oota-llvm.git

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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54174 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/StrongPHIElimination.cpp b/lib/CodeGen/StrongPHIElimination.cpp
index 399e6154184..3d23efec7b0 100644
--- a/lib/CodeGen/StrongPHIElimination.cpp
+++ b/lib/CodeGen/StrongPHIElimination.cpp
@@ -786,21 +786,29 @@ void StrongPHIElimination::mergeLiveIntervals(unsigned primary,
   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);
-  
-  if (RHS.containsOneValue())
+                                   
+  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.begin() == RHS.end())
     LI.removeInterval(RHS.reg);
-  else
-    RHS.removeRange(RangeMergingIn->start, RangeMergingIn->end, true);
-  
-  LHS.addRange(NewRange);
 }
 
 bool StrongPHIElimination::runOnMachineFunction(MachineFunction &Fn) {