Emulating the AT&T 3B2 Computer

Re:Emulating the AT&T 3B2 Computer by cryptonector on Wednesday May 23, 2018 @11:46AM (#17135084)

The CPUs were microprogrammable. It's no surprise that they had a strcpy() opcode. VAXes too had crazy complicated instructions, including list traversal instructions and arbitrary precision BCD instructions (IIRC anyways).

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Re:Emulating the AT&T 3B2 Computer by msla on Wednesday May 23, 2018 @12:02PM (#17135220)

The VAX had a POLY opcode, which evaluated polynomials of arbitrary degree:

http://uranium.vaxpower.org/~isildur/vax/week.html

https://news.ycombinator.com/item?id=9841892

> The table address operand points to a table of polynomial coefficients. The coefficient of the highest-order term of the polynomial is pointed to by the table address operand. The table is specified with lower-order coefficients stored at increasing addresses. The data type of the coefficients is the same as the data type of the argument operand. The evaluation is carried out by Horner's method, and the contents of R0 (R1'R0 for POLYD and POLYG, R3'R2'R1'R0 for POLYH) are replaced by the result.

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