4 ms·
The CDC 6600 (1963) had 60-bit words and both 15-bit and 30-bit instructions, with the restriction that 30-bit instructions couldn't straddle a word boundary.
by pklausler 3y ago
The CDC 6600 (1963) had 60-bit words and both 15-bit and 30-bit instructions, with the restriction that 30-bit instructions couldn't straddle a word boundary. The COMPASS assembler would sometimes have to insert a 15-bit no-op instruction to "force upper". Careful optimizing programmers and compilers would try to minimize "forcing upper" to avoid wasting precious space in the 7-word instruction "stack".
So it's been done, and is not a big deal.
- chx 3y agowas it called assembler though? I was looking and https://web.archive.org/web/20120910064824/http://www.bitsavers.org/pdf/cdc/3x00/24bit/60184200_compassTrng_May67.pdf https://web.archive.org/web/20120910064824/http://www.bitsav... does not say so but http://www.bitsavers.org/pdf/cdc/cyber/cyber_70/60225100_Extended_Core_Storage_System_Ref_Feb68.pdf http://www.bitsavers.org/pdf/cdc/cyber/cyber_70/60225100_Ext... does refer to "COMPASS assembly language". Interesitng.