Workaround for PR2207, in which pred_iterator assert gets triggered due to a

wee problem in Xcode 2.[45]/gcc 4.0.1.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49831 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/Support/CFG.h b/include/llvm/Support/CFG.h
index 937472d5816fd56fecf249765e180aecda7be853..f8cbeb0a50f053553e320912a54cfd8df51ddce1 100644 (file)
--- a/include/llvm/Support/CFG.h
+++ b/include/llvm/Support/CFG.h
@@ -36,8 +36,11 @@ public:
 
   inline void advancePastNonPreds() {
     // Loop to ignore non predecessor uses (for example PHI nodes)...
-    while (!It.atEnd() && !isa<TerminatorInst>(*It) && !isa<BasicBlock>(*It))
+    while (!It.atEnd()) {
+      if (isa<TerminatorInst>(*It) || isa<BasicBlock>(*It))
+       break;
       ++It;
+    }
   }
 
   inline PredIterator(_Ptr *bb) : It(bb->use_begin()) {

diff --git a/lib/Transforms/Utils/BreakCriticalEdges.cpp b/lib/Transforms/Utils/BreakCriticalEdges.cpp
index 1a41d95a03251f8aca3a7d3dddc7e3854cfec9d8..1ff92a8d03276c75777c443671cc31946113dbea 100644 (file)
--- a/lib/Transforms/Utils/BreakCriticalEdges.cpp
+++ b/lib/Transforms/Utils/BreakCriticalEdges.cpp
@@ -103,8 +103,15 @@ bool llvm::isCriticalEdge(const TerminatorInst *TI, unsigned SuccNum,
   
   // If AllowIdenticalEdges is true, then we allow this edge to be considered
   // non-critical iff all preds come from TI's block.
-  for (; I != E; ++I)
-    if (*I != FirstPred) return true;
+  while (I != E) {
+    pred_const_iterator E1 = E;
+    if (*I != FirstPred)
+      return true;
+    // Note: leave this as is until no one ever compiles with either gcc 4.0.1
+    // or Xcode 2. This seems to work around the pred_iterator assert in PR 2207
+    E = pred_end(*I);
+    ++I;
+  }
   return false;
 }