[llvm-commits] [llvm] r37934 - /llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp

[Evan Cheng]

Author: evancheng
Date: Thu Jul  5 20:37:28 2007
New Revision: 37934

URL: http://llvm.org/viewvc/llvm-project?rev=37934&view=rev
Log:
Change CalculateHeights and CalculateDepths to be non-recursive.

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp?rev=37934&r1=37933&r2=37934&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/ScheduleDAG.cpp Thu Jul  5 20:37:28 2007
@@ -179,35 +179,41 @@
   return;
 }
 
-static void CalculateDepths(SUnit &SU, unsigned Depth) {
-  if (SU.Depth == 0 || Depth > SU.Depth) {
-    SU.Depth = Depth;
-    for (SUnit::succ_iterator I = SU.Succs.begin(), E = SU.Succs.end();
-         I != E; ++I)
-      CalculateDepths(*I->first, Depth+1);
-  }
-}
-
 void ScheduleDAG::CalculateDepths() {
-  SUnit *Entry = SUnitMap[DAG.getEntryNode().Val];
-  ::CalculateDepths(*Entry, 0U);
+  std::vector<std::pair<SUnit*, unsigned> > WorkList;
   for (unsigned i = 0, e = SUnits.size(); i != e; ++i)
-    if (SUnits[i].Preds.size() == 0 && &SUnits[i] != Entry) {
-      ::CalculateDepths(SUnits[i], 0U);
-    }
-}
+    if (SUnits[i].Preds.size() == 0/* && &SUnits[i] != Entry*/)
+      WorkList.push_back(std::make_pair(&SUnits[i], 0U));
 
-static void CalculateHeights(SUnit &SU, unsigned Height) {
-  if (SU.Height == 0 || Height > SU.Height) {
-    SU.Height = Height;
-    for (SUnit::pred_iterator I = SU.Preds.begin(), E = SU.Preds.end();
-         I != E; ++I)
-      CalculateHeights(*I->first, Height+1);
+  while (!WorkList.empty()) {
+    SUnit *SU = WorkList.back().first;
+    unsigned Depth = WorkList.back().second;
+    WorkList.pop_back();
+    if (SU->Depth == 0 || Depth > SU->Depth) {
+      SU->Depth = Depth;
+      for (SUnit::succ_iterator I = SU->Succs.begin(), E = SU->Succs.end();
+           I != E; ++I)
+        WorkList.push_back(std::make_pair(I->first, Depth+1));
+    }
   }
 }
+
 void ScheduleDAG::CalculateHeights() {
+  std::vector<std::pair<SUnit*, unsigned> > WorkList;
   SUnit *Root = SUnitMap[DAG.getRoot().Val];
-  ::CalculateHeights(*Root, 0U);
+  WorkList.push_back(std::make_pair(Root, 0U));
+
+  while (!WorkList.empty()) {
+    SUnit *SU = WorkList.back().first;
+    unsigned Height = WorkList.back().second;
+    WorkList.pop_back();
+    if (SU->Height == 0 || Height > SU->Height) {
+      SU->Height = Height;
+      for (SUnit::pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
+           I != E; ++I)
+        WorkList.push_back(std::make_pair(I->first, Height+1));
+    }
+  }
 }
 
 /// CountResults - The results of target nodes have register or immediate