vendor/llvm/llvm-r72732

1 files changed, 40 insertions, 0 deletions

diff --git a/lib/CodeGen/MachineLoopInfo.cpp b/lib/CodeGen/MachineLoopInfo.cpp
new file mode 100644
index 000000000000..68ddb7b3f473
--- /dev/null
+++ b/lib/CodeGen/MachineLoopInfo.cpp
@@ -0,0 +1,40 @@
+//===- MachineLoopInfo.cpp - Natural Loop Calculator ----------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the MachineLoopInfo class that is used to identify natural
+// loops and determine the loop depth of various nodes of the CFG.  Note that
+// the loops identified may actually be several natural loops that share the 
+// same header node... not just a single natural loop.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/MachineLoopInfo.h"
+#include "llvm/CodeGen/MachineDominators.h"
+#include "llvm/CodeGen/Passes.h"
+using namespace llvm;
+
+TEMPLATE_INSTANTIATION(class LoopBase<MachineBasicBlock>);
+TEMPLATE_INSTANTIATION(class LoopInfoBase<MachineBasicBlock>);
+
+char MachineLoopInfo::ID = 0;
+static RegisterPass<MachineLoopInfo>
+X("machine-loops", "Machine Natural Loop Construction", true);
+
+const PassInfo *const llvm::MachineLoopInfoID = &X;
+
+bool MachineLoopInfo::runOnMachineFunction(MachineFunction &) {
+  releaseMemory();
+  LI->Calculate(getAnalysis<MachineDominatorTree>().getBase());    // Update
+  return false;
+}
+
+void MachineLoopInfo::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.setPreservesAll();
+  AU.addRequired<MachineDominatorTree>();
+}