Reapply "[DebugInfo] Use variadic debug values to salvage BinOps and GEP...
Reapply "[DebugInfo] Use variadic debug values to salvage BinOps and GEP instrs with non-const operands"
The causes of the previous build errors have been fixed in revisions
aa3e78a5, and
140757bf
This reverts commit f40976bd.