[clang] [CIR] Add virtual base support to getAddressOfBaseClass (PR #159162)

[Erich Keane via cfe-commits]

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@@ -865,39 +865,55 @@ Address CIRGenFunction::getAddressOfBaseClass(
     bool nullCheckValue, SourceLocation loc) {
   assert(!path.empty() && "Base path should not be empty!");
 
+  CastExpr::path_const_iterator start = path.begin();
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erichkeane wrote:

I was suggesting perhaps using an iterator-range of some sort instead of keeping the begin/end iterators around.  There is a lot of 'move the start' around business, then we just create a range from it instead (880).  I'm suggesting just storing the range here, and moving it around.

https://github.com/llvm/llvm-project/pull/159162