Tagging and Untagging Instructions

Instruction: tag-char s12:dst s12:src

Make a SCM character whose integer value is the u64 in src, and store it in dst.

Instruction: untag-char s12:dst s12:src

Extract the integer value from the SCM character src, and store the resulting u64 in dst.

Instruction: tag-fixnum s12:dst s12:src

Make a SCM integer whose value is the s64 in src, and store it in dst.

Instruction: untag-fixnum s12:dst s12:src

Extract the integer value from the SCM integer src, and store the resulting s64 in dst.