diff --git a/include/llvm/CodeGen/LiveIntervalAnalysis.h b/include/llvm/CodeGen/LiveIntervalAnalysis.h
index 2e238085734..89c72377a84 100644
--- a/include/llvm/CodeGen/LiveIntervalAnalysis.h
+++ b/include/llvm/CodeGen/LiveIntervalAnalysis.h
@@ -24,6 +24,7 @@
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/CodeGen/MachineBasicBlock.h"
 #include <iostream>
+#include <list>
 #include <map>
 
 namespace llvm {
@@ -83,7 +84,7 @@ namespace llvm {
             }
         };
 
-        typedef std::vector<Interval> Intervals;
+        typedef std::list<Interval> Intervals;
         typedef std::vector<MachineBasicBlock*> MachineBasicBlockPtrs;
 
     private:
@@ -100,7 +101,7 @@ namespace llvm {
         typedef std::map<MachineInstr*, unsigned> Mi2IndexMap;
         Mi2IndexMap mi2iMap_;
 
-        typedef std::map<unsigned, unsigned> Reg2IntervalMap;
+        typedef std::map<unsigned, Intervals::iterator> Reg2IntervalMap;
         Reg2IntervalMap r2iMap_;
 
         Intervals intervals_;
diff --git a/include/llvm/CodeGen/LiveIntervals.h b/include/llvm/CodeGen/LiveIntervals.h
index 2e238085734..89c72377a84 100644
--- a/include/llvm/CodeGen/LiveIntervals.h
+++ b/include/llvm/CodeGen/LiveIntervals.h
@@ -24,6 +24,7 @@
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/CodeGen/MachineBasicBlock.h"
 #include <iostream>
+#include <list>
 #include <map>
 
 namespace llvm {
@@ -83,7 +84,7 @@ namespace llvm {
             }
         };
 
-        typedef std::vector<Interval> Intervals;
+        typedef std::list<Interval> Intervals;
         typedef std::vector<MachineBasicBlock*> MachineBasicBlockPtrs;
 
     private:
@@ -100,7 +101,7 @@ namespace llvm {
         typedef std::map<MachineInstr*, unsigned> Mi2IndexMap;
         Mi2IndexMap mi2iMap_;
 
-        typedef std::map<unsigned, unsigned> Reg2IntervalMap;
+        typedef std::map<unsigned, Intervals::iterator> Reg2IntervalMap;
         Reg2IntervalMap r2iMap_;
 
         Intervals intervals_;
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index 6826b4d6492..212bc6f1eb5 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -114,7 +114,7 @@ bool LiveIntervals::runOnMachineFunction(MachineFunction &fn) {
                 unsigned reg = mop.getAllocatedRegNum();
                 Reg2IntervalMap::iterator r2iit = r2iMap_.find(reg);
                 assert(r2iit != r2iMap_.end());
-                intervals_[r2iit->second].weight += pow(10.0F, loopDepth);
+                r2iit->second->weight += pow(10.0F, loopDepth);
             }
         }
     }
@@ -148,11 +148,11 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock* mbb,
         // add new interval
         intervals_.push_back(Interval(reg));
         // update interval index for this register
-        r2iMap_[reg] = intervals_.size() - 1;
+        r2iMap_.insert(std::make_pair(reg, --intervals_.end()));
         interval = &intervals_.back();
     }
     else {
-        interval = &intervals_[r2iit->second];
+        interval = &*r2iit->second;
     }
 
     for (MbbIndex2MbbMap::iterator
@@ -241,15 +241,14 @@ exit:
 
     Reg2IntervalMap::iterator r2iit = r2iMap_.find(reg);
     if (r2iit != r2iMap_.end()) {
-        unsigned ii = r2iit->second;
-        Interval& interval = intervals_[ii];
+        Interval& interval = *r2iit->second;
         interval.addRange(start, end);
     }
     else {
         intervals_.push_back(Interval(reg));
         Interval& interval = intervals_.back();
         // update interval index for this register
-        r2iMap_[reg] = intervals_.size() - 1;
+        r2iMap_.insert(std::make_pair(reg, --intervals_.end()));
         interval.addRange(start, end);
     }
 }
@@ -318,7 +317,7 @@ void LiveIntervals::computeIntervals()
         }
     }
 
-    std::sort(intervals_.begin(), intervals_.end(), StartPointComp());
+    intervals_.sort(StartPointComp());
     DEBUG(std::copy(intervals_.begin(), intervals_.end(),
                     std::ostream_iterator<Interval>(std::cerr, "\n")));
 }
diff --git a/lib/CodeGen/LiveIntervalAnalysis.h b/lib/CodeGen/LiveIntervalAnalysis.h
index 2e238085734..89c72377a84 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.h
+++ b/lib/CodeGen/LiveIntervalAnalysis.h
@@ -24,6 +24,7 @@
 #include "llvm/CodeGen/MachineFunctionPass.h"
 #include "llvm/CodeGen/MachineBasicBlock.h"
 #include <iostream>
+#include <list>
 #include <map>
 
 namespace llvm {
@@ -83,7 +84,7 @@ namespace llvm {
             }
         };
 
-        typedef std::vector<Interval> Intervals;
+        typedef std::list<Interval> Intervals;
         typedef std::vector<MachineBasicBlock*> MachineBasicBlockPtrs;
 
     private:
@@ -100,7 +101,7 @@ namespace llvm {
         typedef std::map<MachineInstr*, unsigned> Mi2IndexMap;
         Mi2IndexMap mi2iMap_;
 
-        typedef std::map<unsigned, unsigned> Reg2IntervalMap;
+        typedef std::map<unsigned, Intervals::iterator> Reg2IntervalMap;
         Reg2IntervalMap r2iMap_;
 
         Intervals intervals_;