"Harmful" doesn't mean "so dead in the water that it doesn't actually have performance gains". Intel wouldn't have integrated SIMD if it didn't work at all; that's not the criticism. Rather, the claim is that the performance gains are not well justified by the technical debt they bring to the architecture. The performance gains are not as good as they could be with the vector approach, which has better dynamic and static code density, doesn't horribly proliferate the instruction set, and allows for tuning without recompilation of code to use different instructions.
For those who don’t get the title reference: ”[Programming Pattern] Considered Harmful” is a title meme that began in 1968 — over fifty years ago — and still going strong today!
It all started with the famous Edsger Dijkstra paper titled “Go To Statement Considered Harmful” [1], which lead to an endless series of subsequent papers later patterned after its title [2].
I agree with the sentiment that this title pattern is overused currently, to the point of being cliche — with perhaps a bit of presumptuousness as well, due to the implicit suggestion that the author’s claim of “Considered Harmful” will withstand the test of time as well as Dijkstra’s paper (though perhaps I’m reading too much into it, in this case).
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"Harmful" doesn't mean "so dead in the water that it doesn't actually have performance gains". Intel wouldn't have integrated SIMD if it didn't work at all; that's not the criticism. Rather, the claim is that the performance gains are not well justified by the technical debt they bring to the architecture. The performance gains are not as good as they could be with the vector approach, which has better dynamic and static code density, doesn't horribly proliferate the instruction set, and allows for tuning without recompilation of code to use different instructions.
For those who don’t get the title reference: ”[Programming Pattern] Considered Harmful” is a title meme that began in 1968 — over fifty years ago — and still going strong today!
It all started with the famous Edsger Dijkstra paper titled “Go To Statement Considered Harmful” [1], which lead to an endless series of subsequent papers later patterned after its title [2].
I agree with the sentiment that this title pattern is overused currently, to the point of being cliche — with perhaps a bit of presumptuousness as well, due to the implicit suggestion that the author’s claim of “Considered Harmful” will withstand the test of time as well as Dijkstra’s paper (though perhaps I’m reading too much into it, in this case).
[1] https://dl.acm.org/citation.cfm?doid=362929.362947
[2] https://en.m.wikipedia.org/wiki/Considered_harmful