[PM] Port domtree to the new pass manager (at last).

This adds the domtree analysis to the new pass manager. The analysis
returns the same DominatorTree result entity used by the old pass
manager and essentially all of the code is shared. We just have
different boilerplate for running and printing the analysis.

I've converted one test to run in both modes just to make sure this is
exercised while both are live in the tree.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225969 91177308-0d34-0410-b5e6-96231b3b80d8

lib/IR/Dominators.cpp

@@ -20,6 +20,7 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/IR/CFG.h"
 #include "llvm/IR/Instructions.h"
+#include "llvm/IR/PassManager.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/Debug.h"
@@ -297,11 +298,46 @@ void DominatorTree::verifyDomTree() const {
   }
 }
 
+//===----------------------------------------------------------------------===//
+//  DominatorTreeAnalysis and related pass implementations
+//===----------------------------------------------------------------------===//
+//
+// This implements the DominatorTreeAnalysis which is used with the new pass
+// manager. It also implements some methods from utility passes.
+//
+//===----------------------------------------------------------------------===//
+
+DominatorTree DominatorTreeAnalysis::run(Function &F) {
+  DominatorTree DT;
+  DT.recalculate(F);
+  return DT;
+}
+
+char DominatorTreeAnalysis::PassID;
+
+DominatorTreePrinterPass::DominatorTreePrinterPass(raw_ostream &OS) : OS(OS) {}
+
+PreservedAnalyses DominatorTreePrinterPass::run(Function &F,
+                                                FunctionAnalysisManager *AM) {
+  OS << "DominatorTree for function: " << F.getName() << "\n";
+  AM->getResult<DominatorTreeAnalysis>(F).print(OS);
+
+  return PreservedAnalyses::all();
+}
+
+PreservedAnalyses DominatorTreeVerifierPass::run(Function &F,
+                                                 FunctionAnalysisManager *AM) {
+  AM->getResult<DominatorTreeAnalysis>(F).verifyDomTree();
+
+  return PreservedAnalyses::all();
+}
+
 //===----------------------------------------------------------------------===//
 //  DominatorTreeWrapperPass Implementation
 //===----------------------------------------------------------------------===//
 //
-// The implementation details of the wrapper pass that holds a DominatorTree.
+// The implementation details of the wrapper pass that holds a DominatorTree
+// suitable for use with the legacy pass manager.
 //
 //===----------------------------------------------------------------------===//