[llvm-commits] [llvm] r42397 - /llvm/trunk/lib/Analysis/IPA/Andersens.cpp

[Daniel Berlin]

Author: dannyb
Date: Thu Sep 27 10:42:23 2007
New Revision: 42397

URL: http://llvm.org/viewvc/llvm-project?rev=42397&view=rev
Log:
Ignore redundant constraints

Modified:
    llvm/trunk/lib/Analysis/IPA/Andersens.cpp

Modified: llvm/trunk/lib/Analysis/IPA/Andersens.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/IPA/Andersens.cpp?rev=42397&r1=42396&r2=42397&view=diff

==============================================================================
--- llvm/trunk/lib/Analysis/IPA/Andersens.cpp (original)
+++ llvm/trunk/lib/Analysis/IPA/Andersens.cpp Thu Sep 27 10:42:23 2007
@@ -134,6 +134,21 @@
         assert(Offset == 0 || Ty != AddressOf &&
                "Offset is illegal on addressof constraints");
       }
+      bool operator==(const Constraint &RHS) const {
+        return RHS.Type == Type
+          && RHS.Dest == Dest
+          && RHS.Src == Src
+          && RHS.Offset == Offset;
+      }
+      bool operator<(const Constraint &RHS) const {
+        if (RHS.Type != Type)
+          return RHS.Type < Type;
+        else if (RHS.Dest != Dest)
+          return RHS.Dest < Dest;
+        else if (RHS.Src != Src)
+          return RHS.Src < Src;
+        return RHS.Offset < Offset;
+      }
     };
 
     // Node class - This class is used to represent a node in the constraint
@@ -1735,6 +1750,7 @@
 /// replaced by their the pointer equivalence class representative.
 void Andersens::RewriteConstraints() {
   std::vector<Constraint> NewConstraints;
+  std::set<Constraint> Seen;
 
   PEClass2Node.clear();
   PENLEClass2Node.clear();
@@ -1768,12 +1784,14 @@
     // it.
     if (C.Src == C.Dest && C.Type == Constraint::Copy)
       continue;
-    
+
     C.Src = FindEquivalentNode(RHSNode, RHSLabel);
     C.Dest = FindEquivalentNode(FindNode(LHSNode), LHSLabel);
-    if (C.Src == C.Dest && C.Type == Constraint::Copy)
+    if (C.Src == C.Dest && C.Type == Constraint::Copy
+        || Seen.count(C) != 0)
       continue;
 
+    Seen.insert(C);
     NewConstraints.push_back(C);
   }
   Constraints.swap(NewConstraints);