[llvm-commits] [llvm] r166501 - /llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

[Nadav Rotem]

Author: nadav
Date: Tue Oct 23 16:05:33 2012
New Revision: 166501

URL: http://llvm.org/viewvc/llvm-project?rev=166501&view=rev
Log:

Make the indirect branch optimization deterministic. No functionality change.

Patch by Daniel Reynaud.


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

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp?rev=166501&r1=166500&r2=166501&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp Tue Oct 23 16:05:33 2012
@@ -2604,14 +2604,14 @@
   MachineBasicBlock *IndirectBrMBB = FuncInfo.MBB;
 
   // Update machine-CFG edges with unique successors.
-  SmallVector<BasicBlock*, 32> succs;
-  succs.reserve(I.getNumSuccessors());
-  for (unsigned i = 0, e = I.getNumSuccessors(); i != e; ++i)
-    succs.push_back(I.getSuccessor(i));
-  array_pod_sort(succs.begin(), succs.end());
-  succs.erase(std::unique(succs.begin(), succs.end()), succs.end());
-  for (unsigned i = 0, e = succs.size(); i != e; ++i) {
-    MachineBasicBlock *Succ = FuncInfo.MBBMap[succs[i]];
+  SmallSet<BasicBlock*, 32> Done;
+  for (unsigned i = 0, e = I.getNumSuccessors(); i != e; ++i) {
+    BasicBlock *BB = I.getSuccessor(i);
+    bool Inserted = Done.insert(BB);
+    if (!Inserted)
+        continue;
+
+    MachineBasicBlock *Succ = FuncInfo.MBBMap[BB];
     addSuccessorWithWeight(IndirectBrMBB, Succ);
   }