1 files changed, 86 insertions, 0 deletions
diff --git a/lib/CodeGen/EdgeBundles.cpp b/lib/CodeGen/EdgeBundles.cpp
new file mode 100644
index 000000000000..aed8bc947991
--- /dev/null
+++ b/lib/CodeGen/EdgeBundles.cpp
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+//===-------- EdgeBundles.cpp - Bundles of CFG edges ----------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides the implementation of the EdgeBundles analysis.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/EdgeBundles.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/GraphWriter.h"
+
+using namespace llvm;
+
+static cl::opt<bool>
+ViewEdgeBundles("view-edge-bundles", cl::Hidden,
+                cl::desc("Pop up a window to show edge bundle graphs"));
+
+char EdgeBundles::ID = 0;
+
+INITIALIZE_PASS(EdgeBundles, "edge-bundles", "Bundle Machine CFG Edges",
+                /* cfg = */true, /* analysis = */ true)
+
+char &llvm::EdgeBundlesID = EdgeBundles::ID;
+
+void EdgeBundles::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.setPreservesAll();
+  MachineFunctionPass::getAnalysisUsage(AU);
+}
+
+bool EdgeBundles::runOnMachineFunction(MachineFunction &mf) {
+  MF = &mf;
+  EC.clear();
+  EC.grow(2 * MF->size());
+
+  for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); I != E;
+       ++I) {
+    const MachineBasicBlock &MBB = *I;
+    unsigned OutE = 2 * MBB.getNumber() + 1;
+    // Join the outgoing bundle with the ingoing bundles of all successors.
+    for (MachineBasicBlock::const_succ_iterator SI = MBB.succ_begin(),
+           SE = MBB.succ_end(); SI != SE; ++SI)
+      EC.join(OutE, 2 * (*SI)->getNumber());
+  }
+  EC.compress();
+  if (ViewEdgeBundles)
+    view();
+  return false;
+}
+
+/// view - Visualize the annotated bipartite CFG with Graphviz.
+void EdgeBundles::view() const {
+  ViewGraph(*this, "EdgeBundles");
+}
+
+/// Specialize WriteGraph, the standard implementation won't work.
+raw_ostream &llvm::WriteGraph(raw_ostream &O, const EdgeBundles &G,
+                              bool ShortNames,
+                              const std::string &Title) {
+  const MachineFunction *MF = G.getMachineFunction();
+
+  O << "digraph {\n";
+  for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
+       I != E; ++I) {
+    unsigned BB = I->getNumber();
+    O << "\t\"BB#" << BB << "\" [ shape=box ]\n"
+      << '\t' << G.getBundle(BB, false) << " -> \"BB#" << BB << "\"\n"
+      << "\t\"BB#" << BB << "\" -> " << G.getBundle(BB, true) << '\n';
+    for (MachineBasicBlock::const_succ_iterator SI = I->succ_begin(),
+           SE = I->succ_end(); SI != SE; ++SI)
+      O << "\t\"BB#" << BB << "\" -> \"BB#" << (*SI)->getNumber()
+        << "\" [ color=lightgray ]\n";
+  }
+  O << "}\n";
+  return O;
+}
+
+