The DOS TP compiler was still at the heart of Delphi 1 supported an inline assembler and reference-based class system, code generator, etc. in less than 43k lines of assembler (it was entirely written in assembler).
(32-bit Delphi 2 switched to a C-based compiler originally written by Peter Sollich. I maintained the front end on that compiler for 6 years; PS followed AH to MS.)
To be clear, I was only involved in 2006-12 time period. I got a lot of use out of TP 6 and Delphi 2 when I was learning, which is a significant part of the reason I ended up at Borland.
(32-bit Delphi 2 switched to a C-based compiler originally written by Peter Sollich. I maintained the front end on that compiler for 6 years; PS followed AH to MS.)