From a46cd97818ac6fa336b093adecf2006fb041ca1c Mon Sep 17 00:00:00 2001
From: Cameron Zwarich <zwarich@apple.com>
Date: Thu, 24 Feb 2011 10:00:13 +0000
Subject: [PATCH] Track blocks visited in reverse postorder.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126377 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/CodeGen/FunctionLoweringInfo.h       | 4 ++++
 lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp | 1 +
 lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp     | 4 ++++
 3 files changed, 9 insertions(+)

diff --git a/include/llvm/CodeGen/FunctionLoweringInfo.h b/include/llvm/CodeGen/FunctionLoweringInfo.h
index 7f03a7a0f71..8b1c852e4f2 100644
--- a/include/llvm/CodeGen/FunctionLoweringInfo.h
+++ b/include/llvm/CodeGen/FunctionLoweringInfo.h
@@ -106,6 +106,10 @@ public:
     LiveOutInfo() : NumSignBits(0), KnownOne(1, 0), KnownZero(1, 0) {}
   };
 
+  /// VisitedBBs - The set of basic blocks visited thus far by instruction
+  /// selection.
+  DenseSet<const BasicBlock*> VisitedBBs;
+
   /// PHINodesToUpdate - A list of phi instructions whose operand list will
   /// be updated after processing the current basic block.
   /// TODO: This isn't per-function state, it's per-basic-block state. But
diff --git a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
index 98582ba99f1..c55cf85a6d2 100644
--- a/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
+++ b/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
@@ -219,6 +219,7 @@ void FunctionLoweringInfo::clear() {
   CatchInfoFound.clear();
 #endif
   LiveOutRegInfo.clear();
+  VisitedBBs.clear();
   ArgDbgValues.clear();
   ByValArgFrameIndexMap.clear();
   RegFixups.clear();
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 835aab25c2a..9d3f5bc7e3b 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -831,6 +831,10 @@ void SelectionDAGISel::SelectAllBasicBlocks(const Function &Fn) {
 #ifndef NDEBUG
     CheckLineNumbers(LLVMBB);
 #endif
+
+    if (OptLevel != CodeGenOpt::None)
+      FuncInfo->VisitedBBs.insert(LLVMBB);
+
     FuncInfo->MBB = FuncInfo->MBBMap[LLVMBB];
     FuncInfo->InsertPt = FuncInfo->MBB->getFirstNonPHI();
 
-- 
2.34.1