From 3084979ff27f48487c7421536144c41a36cae997 Mon Sep 17 00:00:00 2001
From: Andrew Trick <atrick@apple.com>
Date: Fri, 25 Jan 2013 07:45:29 +0000
Subject: [PATCH] MachineScheduler support for viewGraph.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173432 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/CodeGen/MachineScheduler.h |  3 +
 include/llvm/CodeGen/ScheduleDAG.h      |  4 +-
 lib/CodeGen/MachineScheduler.cpp        | 89 ++++++++++++++++++++++++-
 3 files changed, 93 insertions(+), 3 deletions(-)

diff --git a/include/llvm/CodeGen/MachineScheduler.h b/include/llvm/CodeGen/MachineScheduler.h
index aa78f5285af..2e39161d110 100644
--- a/include/llvm/CodeGen/MachineScheduler.h
+++ b/include/llvm/CodeGen/MachineScheduler.h
@@ -325,6 +325,9 @@ public:
 
   BitVector &getScheduledTrees() { return ScheduledTrees; }
 
+  void viewGraph(const Twine &Name, const Twine &Title) LLVM_OVERRIDE;
+  void viewGraph() LLVM_OVERRIDE;
+
 protected:
   // Top-Level entry points for the schedule() driver...
 
diff --git a/include/llvm/CodeGen/ScheduleDAG.h b/include/llvm/CodeGen/ScheduleDAG.h
index 18bef1c4028..67922698106 100644
--- a/include/llvm/CodeGen/ScheduleDAG.h
+++ b/include/llvm/CodeGen/ScheduleDAG.h
@@ -578,8 +578,8 @@ namespace llvm {
     /// viewGraph - Pop up a GraphViz/gv window with the ScheduleDAG rendered
     /// using 'dot'.
     ///
-    void viewGraph(const Twine &Name, const Twine &Title);
-    void viewGraph();
+    virtual void viewGraph(const Twine &Name, const Twine &Title);
+    virtual void viewGraph();
 
     virtual void dumpNode(const SUnit *SU) const = 0;
 
diff --git a/lib/CodeGen/MachineScheduler.cpp b/lib/CodeGen/MachineScheduler.cpp
index aa599158e9e..9072dd4b713 100644
--- a/lib/CodeGen/MachineScheduler.cpp
+++ b/lib/CodeGen/MachineScheduler.cpp
@@ -26,6 +26,7 @@
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/GraphWriter.h"
 #include "llvm/Support/raw_ostream.h"
 #include <queue>
 
@@ -557,7 +558,6 @@ void ScheduleDAGMI::buildDAGWithRegPressure() {
 
   // Build the DAG, and compute current register pressure.
   buildSchedGraph(AA, &RPTracker);
-  if (ViewMISchedDAGs) viewGraph();
 
   // Initialize top/bottom trackers after computing region pressure.
   initRegPressure();
@@ -2294,3 +2294,90 @@ static MachineSchedRegistry ShufflerRegistry(
   "shuffle", "Shuffle machine instructions alternating directions",
   createInstructionShuffler);
 #endif // !NDEBUG
+
+//===----------------------------------------------------------------------===//
+// GraphWriter support for ScheduleDAGMI.
+//===----------------------------------------------------------------------===//
+
+#ifndef NDEBUG
+namespace llvm {
+
+template<> struct GraphTraits<
+  ScheduleDAGMI*> : public GraphTraits<ScheduleDAG*> {};
+
+template<>
+struct DOTGraphTraits<ScheduleDAGMI*> : public DefaultDOTGraphTraits {
+
+  DOTGraphTraits (bool isSimple=false) : DefaultDOTGraphTraits(isSimple) {}
+
+  static std::string getGraphName(const ScheduleDAG *G) {
+    return G->MF.getName();
+  }
+
+  static bool renderGraphFromBottomUp() {
+    return true;
+  }
+
+  static bool isNodeHidden(const SUnit *Node) {
+    return (Node->NumPreds > 10 || Node->NumSuccs > 10);
+  }
+
+  static bool hasNodeAddressLabel(const SUnit *Node,
+                                  const ScheduleDAG *Graph) {
+    return false;
+  }
+
+  /// If you want to override the dot attributes printed for a particular
+  /// edge, override this method.
+  static std::string getEdgeAttributes(const SUnit *Node,
+                                       SUnitIterator EI,
+                                       const ScheduleDAG *Graph) {
+    if (EI.isArtificialDep())
+      return "color=cyan,style=dashed";
+    if (EI.isCtrlDep())
+      return "color=blue,style=dashed";
+    return "";
+  }
+
+  static std::string getNodeLabel(const SUnit *SU, const ScheduleDAG *G) {
+    std::string Str;
+    raw_string_ostream SS(Str);
+    SS << "SU(" << SU->NodeNum << ')';
+    return SS.str();
+  }
+  static std::string getNodeDescription(const SUnit *SU, const ScheduleDAG *G) {
+    return G->getGraphNodeLabel(SU);
+  }
+
+  static std::string getNodeAttributes(const SUnit *N,
+                                       const ScheduleDAG *Graph) {
+    std::string Str("shape=Mrecord");
+    const SchedDFSResult *DFS =
+      static_cast<const ScheduleDAGMI*>(Graph)->getDFSResult();
+    if (DFS) {
+      Str += ",style=filled,fillcolor=\"#";
+      Str += DOT::getColorString(DFS->getSubtreeID(N));
+      Str += '"';
+    }
+    return Str;
+  }
+};
+} // namespace llvm
+#endif // NDEBUG
+
+/// viewGraph - Pop up a ghostview window with the reachable parts of the DAG
+/// rendered using 'dot'.
+///
+void ScheduleDAGMI::viewGraph(const Twine &Name, const Twine &Title) {
+#ifndef NDEBUG
+  ViewGraph(this, Name, false, Title);
+#else
+  errs() << "ScheduleDAGMI::viewGraph is only available in debug builds on "
+         << "systems with Graphviz or gv!\n";
+#endif  // NDEBUG
+}
+
+/// Out-of-line implementation with no arguments is handy for gdb.
+void ScheduleDAGMI::viewGraph() {
+  viewGraph(getDAGName(), "Scheduling-Units Graph for " + getDAGName());
+}