simd_fpow and simd_fpowi intrinsics are not exposed in intrinsics::simd
#137555
Labels
A-SIMD
Area: SIMD (Single Instruction Multiple Data)
F-core_intrinsics
Issue in the "core intrinsics" for internal usage only.
needs-triage
This issue may need triage. Remove it if it has been sufficiently triaged.
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rustbot
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As far as I can see, neither stdarch nor portable-simd use these intrinsics. So... should we just remove them? Or is there a reason for them to exist? |
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None of the targets/instruction sets I could think of seem to do anything smart https://godbolt.org/z/KP1K66nhP they just seem to spill to the stack and use the standard scalar |
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then I'm pro-yeet, assuming there isn't something special I don't remember |
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Odd that they don't do much at all. Seems ok to remove them to me, we can re-add (working) intrinsics if we try to expose a function that needs it |
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@folkertdev are you planning to make a PR that removes them? :) |
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Yes |
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I opened #137595 |
fmease
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…=RalfJung remove `simd_fpow` and `simd_fpowi` Discussed in rust-lang#137555 These functions are not exposed from `std::intrinsics::simd`, and not used anywhere outside of the compiler. They also don't lower to particularly good code at least on the major ISAs (I checked x86_64, aarch64, s390x, powerpc), where the vector is just spilled to the stack and scalar functions are used for the actual logic. r? `@RalfJung`
rust-timer
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Rollup merge of rust-lang#137595 - folkertdev:remove-simd-pow-powi, r=RalfJung remove `simd_fpow` and `simd_fpowi` Discussed in rust-lang#137555 These functions are not exposed from `std::intrinsics::simd`, and not used anywhere outside of the compiler. They also don't lower to particularly good code at least on the major ISAs (I checked x86_64, aarch64, s390x, powerpc), where the vector is just spilled to the stack and scalar functions are used for the actual logic. r? `@RalfJung`
bjorn3
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Feb 26, 2025
remove `simd_fpow` and `simd_fpowi` Discussed in rust-lang/rust#137555 These functions are not exposed from `std::intrinsics::simd`, and not used anywhere outside of the compiler. They also don't lower to particularly good code at least on the major ISAs (I checked x86_64, aarch64, s390x, powerpc), where the vector is just spilled to the stack and scalar functions are used for the actual logic. r? `@RalfJung`
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As a result, to test/use these intrinsics they must be redeclared outside of
core, which is at best inelegant and at worst could lead to subtle bugs.I think there are two options:
cc @calebzulawski it looks like you touched this last 5 years ago 07db2bf. Long time, but maybe you remember something?
@rustbot label +A-simd +F-core_intrinsics
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