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

1 files changed, 4 insertions, 0 deletions

diff --git a/lib/CodeGen/VirtRegMap.cpp b/lib/CodeGen/VirtRegMap.cpp
index 5bdc1fff68..a69a8169d3 100644
--- a/lib/CodeGen/VirtRegMap.cpp
+++ b/lib/CodeGen/VirtRegMap.cpp
@@ -20,6 +20,7 @@
 #include "VirtRegMap.h"
 #include "LiveDebugVariables.h"
 #include "llvm/CodeGen/LiveIntervalAnalysis.h"
+#include "llvm/CodeGen/LiveStackAnalysis.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
@@ -171,6 +172,7 @@ INITIALIZE_PASS_BEGIN(VirtRegRewriter, "virtregrewriter",
 INITIALIZE_PASS_DEPENDENCY(SlotIndexes)
 INITIALIZE_PASS_DEPENDENCY(LiveIntervals)
 INITIALIZE_PASS_DEPENDENCY(LiveDebugVariables)
+INITIALIZE_PASS_DEPENDENCY(LiveStacks)
 INITIALIZE_PASS_DEPENDENCY(VirtRegMap)
 INITIALIZE_PASS_END(VirtRegRewriter, "virtregrewriter",
                     "Virtual Register Rewriter", false, false)
@@ -183,6 +185,8 @@ void VirtRegRewriter::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.addRequired<SlotIndexes>();
   AU.addPreserved<SlotIndexes>();
   AU.addRequired<LiveDebugVariables>();
+  AU.addRequired<LiveStacks>();
+  AU.addPreserved<LiveStacks>();
   AU.addRequired<VirtRegMap>();
   MachineFunctionPass::getAnalysisUsage(AU);
 }