Change PHINode::hasConstantValue to have a DominatorTree argument
instead of a bool argument, and to do the dominator check itself.
This makes it eaiser to use when DominatorTree information is
available.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80920 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/BasicBlockUtils.cpp b/lib/Transforms/Utils/BasicBlockUtils.cpp
index c3d6194..c165e04 100644
--- a/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -429,13 +429,10 @@
     PN->addIncoming(InVal, NewBB);
     
     // Check to see if we can eliminate this phi node.
-    if (Value *V = PN->hasConstantValue(DT != 0)) {
-      Instruction *I = dyn_cast<Instruction>(V);
-      if (!I || DT == 0 || DT->dominates(I, PN)) {
-        PN->replaceAllUsesWith(V);
-        if (AA) AA->deleteValue(PN);
-        PN->eraseFromParent();
-      }
+    if (Value *V = PN->hasConstantValue(DT)) {
+      PN->replaceAllUsesWith(V);
+      if (AA) AA->deleteValue(PN);
+      PN->eraseFromParent();
     }
   }