switch ValueMap to using AssertingVH.  This is an old patch I had laying
around in a tree I forgot about.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78048 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Bitcode/Writer/BitcodeWriter.cpp b/lib/Bitcode/Writer/BitcodeWriter.cpp
index 4b92516..724e1ae 100644
--- a/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -1083,7 +1083,7 @@
     // VST_ENTRY:   [valueid, namechar x N]
     // VST_BBENTRY: [bbid, namechar x N]
     unsigned Code;
-    if (isa<BasicBlock>(SI->getValue())) {
+    if (isa<BasicBlock>(*SI->getValue())) {
       Code = bitc::VST_CODE_BBENTRY;
       if (isChar6)
         AbbrevToUse = VST_BBENTRY_6_ABBREV;