[llvm-commits] [llvm] r48106 - /llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp

[Nick Lewycky]

Author: nicholas
Date: Sun Mar  9 03:50:23 2008
New Revision: 48106

URL: http://llvm.org/viewvc/llvm-project?rev=48106&view=rev
Log:
Don't eliminate blocks that are only reachable by unwind_to.

Modified:
    llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp

Modified: llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp?rev=48106&r1=48105&r2=48106&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/InstructionCombining.cpp Sun Mar  9 03:50:23 2008
@@ -10796,11 +10796,15 @@
 
     // Recursively visit successors.  If this is a branch or switch on a
     // constant, only visit the reachable successor.
+    if (BB->getUnwindDest())
+      Worklist.push_back(BB->getUnwindDest());
     TerminatorInst *TI = BB->getTerminator();
     if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
       if (BI->isConditional() && isa<ConstantInt>(BI->getCondition())) {
         bool CondVal = cast<ConstantInt>(BI->getCondition())->getZExtValue();
-        Worklist.push_back(BI->getSuccessor(!CondVal));
+        BasicBlock *ReachableBB = BI->getSuccessor(!CondVal);
+        if (ReachableBB != BB->getUnwindDest())
+          Worklist.push_back(ReachableBB);
         continue;
       }
     } else if (SwitchInst *SI = dyn_cast<SwitchInst>(TI)) {
@@ -10808,7 +10812,9 @@
         // See if this is an explicit destination.
         for (unsigned i = 1, e = SI->getNumSuccessors(); i != e; ++i)
           if (SI->getCaseValue(i) == Cond) {
-            Worklist.push_back(SI->getSuccessor(i));
+            BasicBlock *ReachableBB = SI->getSuccessor(i);
+            if (ReachableBB != BB->getUnwindDest())
+              Worklist.push_back(ReachableBB);
             continue;
           }