alt Hacker NewsFor those unfamiliar with the Hitachi SuperH architecture, imagine THUMB. ARM even had to license some of the patents from Hitchai when they developed THUMB. SuperH architecture is not the same thing as THUMB, but it has a lot in common, mainly use of 16-bit instructions, and instructions that only specify two registers rather than three.
But it also has some RISC jank of the era, such as branch delay slots.
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cakehonolulu • yesterday at 10:52 PM
I actually didn't know the THUMB thing; pretty interesting stuff...
The branch delay slots/load delay slots thing was also something that plagued some MIPS processors back then too; 5th generation of consoles (At least, from Sony, Nintendo and Sega) had either all or a subset of those quirks on their flagship machines.
> 16-bit instructions, and instructions that only specify two registers rather than three
These are not strange design features. I'm surprised they were patented? For example, most non-SIMD x86 instructions are two-operand. The trade-off between two-operand and three-operand has been known for a long time. (Shorter instruction encodings, but sometimes you need more instructions)