No, but I tend think of it in terms similar to those expressed by Rob Finch on another thread.
robfinch wrote:
I think our understanding of computing systems has grown progressively, and as a consequence we have lost some of the simplicity. In order to achieve high levels of performance and reliability, things like virtual memory and encryption are required, and they add complexity to the systems.
In the case of AMD, the 29k family just did not do as well commercially as the their x86 architecture. To keep 29k's performance in step with the performance improvements made in the x86 architecture, additional technical resources were needed and the ROI just wasn't there. I think the same same can be said for the MIPS and SPARC architectures, although MIPS continues commercially in some Microchip products. ARM's volume provided the company the necessary resources to keep improving the architecture on the performance front.
A GHz-class processor requires much more complexity to perform adequately, and that complexity requires significant technical resources to achieve. In the case of ARM, some of the technical improvements in the architecture are driven by the licensing model that ARM employs. IOW, Apple (and other licensees) provide some of the technology that drives the improvements in the processor architecture. The large volumes that ARM has in the various markets it services provides the resources that are needed to maintain the architecture and drive improved performance.
I use ARMs, PICs, and other processors in some of the products that we design. We are increasingly using ARM-based microcomputers / microcontrollers in our newer products because the licensees add peripheral functions to the base architecture that are better matched to the industries we support. ARM itself is not doing that work, it is the licensees themselves that are developing and improving their own chips based on the core ARM licensed to them. I don't typically use GHz-class ARM processors, but a 60-120 MHz ARM core executes the algorithms that we originally ran on 8051 and 68HC11 microcomputers much faster.
The point is that with the exception of ARM, the other main RISC processor architectures were sourced by a single shop, and they were focused on competing primarily with x86-based computers. When their offerings could
not increase market share, they didn't shift their IP model. ARM shifted to their IP model decades ago, and they are now penetrating the market that would have been occupied by x86 if that architecture had been able to lower their power utilization requirements.
I used to be adamantly opposed to anything x86, but now I will use either x86 or ARM, and the decision is based primarily on power / thermal management and security issues, or whether the application must run on Windows, Linux, or both. The other architectures, including PowerPC, just have not achieved the same performance levels as provided by x86 or ARM, and that is primarily driven by the lack of resources, which in turn, is driven by a lack of market.