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A comment on Major Changes at RISC-V Designer SiFive. Parent comment

Re:Major Changes at RISC-V Designer SiFive by pklausler on Tuesday October 24, 2023 @04:14PM (#38004809)
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.

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Re:Major Changes at RISC-V Designer SiFive by chx on Tuesday October 24, 2023 @05:02PM (#38005541)
was it called assembler though? I was looking and https://web.archive.org/web/20120910064824/http://www.bitsav... does not say so but http://www.bitsavers.org/pdf/cdc/cyber/cyber_70/60225100_Ext... does refer to "COMPASS assembly language". Interesitng.
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