Fix a significant recent(?) regression. StackSlotColoring no longer did anything
because LiveStackAnalysis was not preserved by VirtRegWriter. This caused
big stack usage regression in some cases.

rdar://12340383


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164408 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveStackAnalysis.cpp b/lib/CodeGen/LiveStackAnalysis.cpp
index 939e795..f0b522b 100644
--- a/lib/CodeGen/LiveStackAnalysis.cpp
+++ b/lib/CodeGen/LiveStackAnalysis.cpp
@@ -25,7 +25,10 @@
 using namespace llvm;
 
 char LiveStacks::ID = 0;
-INITIALIZE_PASS(LiveStacks, "livestacks",
+INITIALIZE_PASS_BEGIN(LiveStacks, "livestacks",
+                "Live Stack Slot Analysis", false, false)
+INITIALIZE_PASS_DEPENDENCY(SlotIndexes)
+INITIALIZE_PASS_END(LiveStacks, "livestacks",
                 "Live Stack Slot Analysis", false, false)
 
 char &llvm::LiveStacksID = LiveStacks::ID;