teach ipsccp and ipconstprop that a blockaddress doesn't 'take the address' of a function
in a way that should prevent ip constprop.  This allows clang/test/CodeGen/indirect-goto.c
to pass with the new indirect goto lowering.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85709 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/SCCP.cpp b/lib/Transforms/Scalar/SCCP.cpp
index 4e5fae8..a348e20 100644
--- a/lib/Transforms/Scalar/SCCP.cpp
+++ b/lib/Transforms/Scalar/SCCP.cpp
@@ -1680,12 +1680,14 @@
         return true;  // Storing addr of GV.
     } else if (isa<InvokeInst>(*UI) || isa<CallInst>(*UI)) {
       // Make sure we are calling the function, not passing the address.
-      CallSite CS = CallSite::get(cast<Instruction>(*UI));
-      if (CS.hasArgument(GV))
+      if (UI.getOperandNo() != 0)
         return true;
     } else if (LoadInst *LI = dyn_cast<LoadInst>(*UI)) {
       if (LI->isVolatile())
         return true;
+    } else if (isa<BlockAddress>(*UI)) {
+      // blockaddress doesn't take the address of the function, it takes addr
+      // of label.
     } else {
       return true;
     }