Tanenbaum also believed that the Intel x86 was on the way out, the very CPU that Linux was hard-coded to run on. On the other hand, Minix was ready to adopt the upcoming RISC tech, which Tanenbaum believed would drive the x86 into extinction.
Depends if you count ARM too. I was always confused between RISC and RISC-V, and what ARM has anything to do. As I understand ARM is based on RISC, but its closed source. And RISC-V is based on RISC, but open source. Is that correct?
So is ARM. Every ARM processor is basically uniq, and that makes it efficient. That’s the point of it. RISC as a design philosophy doesn’t take over the industry, its specific implementations. My question is not what RISC is, but if ARM is based on RISC and how close it is in their designs to RISC-V. As I understand the company behind ARM took the RISC philosophy and created a closed source system.
ARM is a well-defined instruction set architecture (ISA), that in order to implement, must comply with that instruction set and be compatible with other implementations from other vendors.
RISC is not any specific ISA at all, but is rather a more generic term for any ISA that has a small amount of instructions.
RISC-V, on the other hand, is a well-defined ISA whose implementations are intercompatible with each other. RISC-V is a very specific, royalty-free ISA that comes out of UC Berkeley that adopts the RISC philosophy.
ARM is a well-defined instruction set architecture (ISA), that in order to implement, must comply with that instruction set and be compatible with other implementations from other vendors.
But that’s not true. ARM isn’t well defined and a single standard, like x86 are. ARM devices are not compatible to each other necessarily. I just had the genius idea to lookup online, I should have done that instead wondering what it is. According to Wikipedia: https://en.wikipedia.org/wiki/ARM_architecture_family
ARM (stylised in lowercase as arm)[a] is a family of RISC instruction set architectures for computer processors.
The original Berkeley RISC designs were in some sense teaching systems, not designed specifically for outright performance. To the RISC’s basic register-heavy and load/store concepts, ARM added a number of the well-received design notes of the 6502.
So I was correct after all. Also ARM is around since 41 years.
Yes, ARM is RISC but it is also well-defined. ARMv9 is backwards compatible with ARMv8. ARMv8 and v9 are 64-bit while ARMv7 and before were 32-bit. Even ARMv9 is technically compatible with ARMv7 because of Aarch32 but that’s optional. ARM’s versioning is more numerous than x86-64 (which also has v2, v3, etc) but that doesn’t mean it’s not well defined.
ARM has multiple revisions that are incompatible with each other, such as ARMv7 being incompatible with AARCH64, but each ARMv7 implementation is compatible with other ARMv7 implementations, and each AARCH64 implementation is comaptible with other ARCH64 implementations, otherwise something like Android APKs or Linux binaries built for AARCH64 would only be able to be run on SoCs from a single company instead of being able to run on SoCs from Qualcomm, Samsung, Nvidia, and Mediatek just the same like they are.
Just because ARM does not maintain backwards compatability does not invalidate my point.
ARM is absolutely RISC. It stands for Acorn Risc Machines (or maybe it’s “Advanced” now?), and was even then a very cool and promising idea, although it lagged behind in speed for a long time. Until the StrongArm came out, I think.
That’s… debatable. While the R in ARM does stand for RISC, there are way too many instructions in the base instruction set of the latest ARM ISA for me to comfortably call it a RISC architecture, especially when compared to RISC-V, which has an extremely slim base instruction set comparatively.
A genuine Nostradamus, here.
Kinda wish he was right about risc tbh
I would argue he was, but it’s taking far longer than I’d like
Depends if you count ARM too. I was always confused between RISC and RISC-V, and what ARM has anything to do. As I understand ARM is based on RISC, but its closed source. And RISC-V is based on RISC, but open source. Is that correct?
RISC isn’t a specific architecture, but moreso a design philosophy.
So is ARM. Every ARM processor is basically uniq, and that makes it efficient. That’s the point of it. RISC as a design philosophy doesn’t take over the industry, its specific implementations. My question is not what RISC is, but if ARM is based on RISC and how close it is in their designs to RISC-V. As I understand the company behind ARM took the RISC philosophy and created a closed source system.
ARM is a well-defined instruction set architecture (ISA), that in order to implement, must comply with that instruction set and be compatible with other implementations from other vendors.
RISC is not any specific ISA at all, but is rather a more generic term for any ISA that has a small amount of instructions.
RISC-V, on the other hand, is a well-defined ISA whose implementations are intercompatible with each other. RISC-V is a very specific, royalty-free ISA that comes out of UC Berkeley that adopts the RISC philosophy.
But that’s not true. ARM isn’t well defined and a single standard, like x86 are. ARM devices are not compatible to each other necessarily. I just had the genius idea to lookup online, I should have done that instead wondering what it is. According to Wikipedia: https://en.wikipedia.org/wiki/ARM_architecture_family
So I was correct after all. Also ARM is around since 41 years.
Yes, ARM is RISC but it is also well-defined. ARMv9 is backwards compatible with ARMv8. ARMv8 and v9 are 64-bit while ARMv7 and before were 32-bit. Even ARMv9 is technically compatible with ARMv7 because of Aarch32 but that’s optional. ARM’s versioning is more numerous than x86-64 (which also has v2, v3, etc) but that doesn’t mean it’s not well defined.
ARM has multiple revisions that are incompatible with each other, such as ARMv7 being incompatible with AARCH64, but each ARMv7 implementation is compatible with other ARMv7 implementations, and each AARCH64 implementation is comaptible with other ARCH64 implementations, otherwise something like Android APKs or Linux binaries built for AARCH64 would only be able to be run on SoCs from a single company instead of being able to run on SoCs from Qualcomm, Samsung, Nvidia, and Mediatek just the same like they are.
Just because ARM does not maintain backwards compatability does not invalidate my point.
ARM is absolutely RISC. It stands for Acorn Risc Machines (or maybe it’s “Advanced” now?), and was even then a very cool and promising idea, although it lagged behind in speed for a long time. Until the StrongArm came out, I think.
https://arm.jonpalmisc.com/latest_aarch64/index.html (Just the base instruction set for the latest ARM architecture without any extensions)
https://en.wikipedia.org/wiki/RISC-V_instruction_listings (Look at just the I instructions for the base instruction set without the extensions)
That’s… debatable. While the R in ARM does stand for RISC, there are way too many instructions in the base instruction set of the latest ARM ISA for me to comfortably call it a RISC architecture, especially when compared to RISC-V, which has an extremely slim base instruction set comparatively.
IBM PC and Apple Mac are both based on the same thing: the idea of a personal computer. IBM PC even put “PC” in the name.
You can definitely tell that they were designed with similar principles in mind, but they are not in any way compatible on a technical level.
ARM and RISC-V are both based on the same thing: the idea of a reduced instruction set. RISC-V even put “RISC” in the name.
You can definitely tell that they were designed with similar principles in mind, but they are not in any way compatible on a technical level.