Implement the final (hopefully) wrinkle to i-c-e + builtin_constant_p 
processing: it allows arbitrary foldable constants as the operand of ?: when
builtin_constant_p is the condition.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@60954 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/InternalsManual.html b/docs/InternalsManual.html
index 5d32d8d..531e576 100644
--- a/docs/InternalsManual.html
+++ b/docs/InternalsManual.html
@@ -1155,7 +1155,8 @@
     constant expression) if the operand is any evaluatable constant.  As a
     special case, if <tt>__builtin_constant_p</tt> is the (potentially
     parenthesized) condition of a conditional operator expression ("?:"), only
-    the true side of the conditional operator is considered.</li>
+    the true side of the conditional operator is considered, and it is evaluated
+    with full constant folding.</li>
 <li><b><tt>__builtin_choose_expr</tt></b>: The condition is required to be an
     integer constant expression, but we accept any constant as an "extension of
     an extension".  This only evaluates one operand depending on which way the