These two values correspond to the 'Empty' and 'Tombstone' special
keys defined by DenseMapInfo<int64_t>, which means that neither one
can be used as a key in DenseMap<int64_t, anything>. Hence, if you try
to use either of those values as an int literal, IntInit::get() fails
an assertion when it tries to insert them into its static cache of
int-literal objects.
Fixed by replacing the DenseMap with a std::map, which doesn't intrude
on the space of legal values of the key type.
Reviewers: nhaehnle, hfinkel, javedabsar, efriedma
Reviewed By: efriedma
Subscribers: fhahn, efriedma, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59016
llvm-svn: 355900
Simon Tatham