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I really like the idea of VLIW CPUs, it's a shame none of them have worked out. Does anyone know of any other cool more modern CPU designs? Stuff like RISCV is

I really like the idea of VLIW CPUs, it's a shame none of them have worked out. Does anyone know of any other cool more modern CPU designs? Stuff like RISCV is fine but doesn't feel particularly innovative

quux 3y ago
The mill architecture has interesting ideas but as far as I know it’s never made it past simulation and there hasn’t been much progress lately. https://millcomputing.com/ https://millcomputing.com/
- Symmetry 3y ago
  They had a bunch of really interesting ideas but trying to innovate in more ways at once brings exponentially more risk. And there weren't only trying to reconceptialize how computers worked, they also were doing a weird innovative corporate structure too. Once the patents expire I hope someone makes a RISC-V design that just tries to get their, e.g., virtual and backless memory working with Linux. That seems like it would be worthwhile in and of itself.
fulafel 3y ago
There have been successful VLIWs in eg GPUs and mobile basebands. Ie in apps that don't have the software inertia of needing to run existing CPU code. Parallel unfriendly C/C++ semantics is the killer.
voxadam 3y ago
VLIW architecture is far from uncommon in DSPs (digital signal processors). TI, NXP, Fujitsu, and plenty of other companies with names less likely to be know by most people focused on general purpose computing currently manufacture massive quantities of VLIW based DSPs.
Symmetry 3y ago
The Hexagon DSPs in Qualcomm's Snapdragon SoC line are VLIWs. Also, NVidia used some cores from the Transmeta lineage in some of its mobile SoCs for application cores. There was a program that ran on them that automatically rewrote ARM instructions to their own ISA that not only was VLIW but was a skewed pipeline VLIW! That's what the Mill guys call phasing, see here: https://millcomputing.com/wiki/Phasing https://millcomputing.com/wiki/Phasing

quux 3y ago

The mill architecture has interesting ideas but as far as I know it’s never made it past simulation and there hasn’t been much progress lately. https://millcomputing.com/ https://millcomputing.com/

Symmetry 3y ago
They had a bunch of really interesting ideas but trying to innovate in more ways at once brings exponentially more risk. And there weren't only trying to reconceptialize how computers worked, they also were doing a weird innovative corporate structure too. Once the patents expire I hope someone makes a RISC-V design that just tries to get their, e.g., virtual and backless memory working with Linux. That seems like it would be worthwhile in and of itself.

fulafel 3y ago

There have been successful VLIWs in eg GPUs and mobile basebands. Ie in apps that don't have the software inertia of needing to run existing CPU code. Parallel unfriendly C/C++ semantics is the killer.

voxadam 3y ago

VLIW architecture is far from uncommon in DSPs (digital signal processors). TI, NXP, Fujitsu, and plenty of other companies with names less likely to be know by most people focused on general purpose computing currently manufacture massive quantities of VLIW based DSPs.

Symmetry 3y ago

The Hexagon DSPs in Qualcomm's Snapdragon SoC line are VLIWs. Also, NVidia used some cores from the Transmeta lineage in some of its mobile SoCs for application cores. There was a program that ran on them that automatically rewrote ARM instructions to their own ISA that not only was VLIW but was a skewed pipeline VLIW! That's what the Mill guys call phasing, see here: https://millcomputing.com/wiki/Phasing https://millcomputing.com/wiki/Phasing