simd_shuffle cleanup: make the mask argument a vector (instead of an array) #128738
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rustbot
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RalfJung
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FYI @oli-obk (making the hack a bit less hacky ;) |
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yay. Moving stdarch to josh first would help so many of these projects |
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Yeah, it would, but Amanieu had some concerns regarding CI. |
workingjubilee
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…rkingjubilee simd_shuffle intrinsic: allow argument to be passed as vector See rust-lang#128738 for context. I'd like to get rid of [this hack](https://github.com/rust-lang/rust/blob/6c0b89dfac65be9a5be12f938f23098ebc36c635/compiler/rustc_codegen_ssa/src/mir/block.rs#L922-L935). rust-lang#128537 almost lets us do that since constant SIMD vectors will then be passed as immediate arguments. However, simd_shuffle for some reason actually takes an *array* as argument, not a vector, so the hack is still required to ensure that the array becomes an immediate (which then later stages of codegen convert into a vector, as that's what LLVM needs). This PR prepares simd_shuffle to also support a vector as the `idx` argument. Once this lands, stdarch can hopefully be updated to pass `idx` as a vector, and then support for arrays can be removed, which finally lets us get rid of that hack.
tgross35
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…rkingjubilee simd_shuffle intrinsic: allow argument to be passed as vector See rust-lang#128738 for context. I'd like to get rid of [this hack](https://github.com/rust-lang/rust/blob/6c0b89dfac65be9a5be12f938f23098ebc36c635/compiler/rustc_codegen_ssa/src/mir/block.rs#L922-L935). rust-lang#128537 almost lets us do that since constant SIMD vectors will then be passed as immediate arguments. However, simd_shuffle for some reason actually takes an *array* as argument, not a vector, so the hack is still required to ensure that the array becomes an immediate (which then later stages of codegen convert into a vector, as that's what LLVM needs). This PR prepares simd_shuffle to also support a vector as the `idx` argument. Once this lands, stdarch can hopefully be updated to pass `idx` as a vector, and then support for arrays can be removed, which finally lets us get rid of that hack.
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Rollup merge of rust-lang#128731 - RalfJung:simd-shuffle-vector, r=workingjubilee simd_shuffle intrinsic: allow argument to be passed as vector See rust-lang#128738 for context. I'd like to get rid of [this hack](https://github.com/rust-lang/rust/blob/6c0b89dfac65be9a5be12f938f23098ebc36c635/compiler/rustc_codegen_ssa/src/mir/block.rs#L922-L935). rust-lang#128537 almost lets us do that since constant SIMD vectors will then be passed as immediate arguments. However, simd_shuffle for some reason actually takes an *array* as argument, not a vector, so the hack is still required to ensure that the array becomes an immediate (which then later stages of codegen convert into a vector, as that's what LLVM needs). This PR prepares simd_shuffle to also support a vector as the `idx` argument. Once this lands, stdarch can hopefully be updated to pass `idx` as a vector, and then support for arrays can be removed, which finally lets us get rid of that hack.
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simd_shuffle intrinsic: allow argument to be passed as vector See rust-lang/rust#128738 for context. I'd like to get rid of [this hack](https://github.com/rust-lang/rust/blob/6c0b89dfac65be9a5be12f938f23098ebc36c635/compiler/rustc_codegen_ssa/src/mir/block.rs#L922-L935). rust-lang/rust#128537 almost lets us do that since constant SIMD vectors will then be passed as immediate arguments. However, simd_shuffle for some reason actually takes an *array* as argument, not a vector, so the hack is still required to ensure that the array becomes an immediate (which then later stages of codegen convert into a vector, as that's what LLVM needs). This PR prepares simd_shuffle to also support a vector as the `idx` argument. Once this lands, stdarch can hopefully be updated to pass `idx` as a vector, and then support for arrays can be removed, which finally lets us get rid of that hack.
bjorn3
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simd_shuffle intrinsic: allow argument to be passed as vector See rust-lang/rust#128738 for context. I'd like to get rid of [this hack](https://github.com/rust-lang/rust/blob/6c0b89dfac65be9a5be12f938f23098ebc36c635/compiler/rustc_codegen_ssa/src/mir/block.rs#L922-L935). rust-lang/rust#128537 almost lets us do that since constant SIMD vectors will then be passed as immediate arguments. However, simd_shuffle for some reason actually takes an *array* as argument, not a vector, so the hack is still required to ensure that the array becomes an immediate (which then later stages of codegen convert into a vector, as that's what LLVM needs). This PR prepares simd_shuffle to also support a vector as the `idx` argument. Once this lands, stdarch can hopefully be updated to pass `idx` as a vector, and then support for arrays can be removed, which finally lets us get rid of that hack.
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…r=compiler-errors simd_shuffle: require index argument to be a vector Remove some codegen hacks by forcing the SIMD shuffle `index` argument to be a vector, which means (thanks to rust-lang#128537) that it will automatically be passed as an immediate in LLVM. The only special-casing we still have is for the extra sanity-checks we add that ensure that the indices are all in-bounds. (And the GCC backend needs to do a bunch of work since the Rust intrinsic is modeled after what LLVM expects, which seems to be quite different from what GCC expects.) Fixes rust-lang#128738, see that issue for more context.
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…compiler-errors simd_shuffle: require index argument to be a vector Remove some codegen hacks by forcing the SIMD shuffle `index` argument to be a vector, which means (thanks to rust-lang#128537) that it will automatically be passed as an immediate in LLVM. The only special-casing we still have is for the extra sanity-checks we add that ensure that the indices are all in-bounds. (And the GCC backend needs to do a bunch of work since the Rust intrinsic is modeled after what LLVM expects, which seems to be quite different from what GCC expects.) Fixes rust-lang#128738, see that issue for more context.
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Rollup merge of rust-lang#130268 - RalfJung:simd-shuffle-idx-vector, r=compiler-errors simd_shuffle: require index argument to be a vector Remove some codegen hacks by forcing the SIMD shuffle `index` argument to be a vector, which means (thanks to rust-lang#128537) that it will automatically be passed as an immediate in LLVM. The only special-casing we still have is for the extra sanity-checks we add that ensure that the indices are all in-bounds. (And the GCC backend needs to do a bunch of work since the Rust intrinsic is modeled after what LLVM expects, which seems to be quite different from what GCC expects.) Fixes rust-lang#128738, see that issue for more context.
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…r-errors simd_shuffle: require index argument to be a vector Remove some codegen hacks by forcing the SIMD shuffle `index` argument to be a vector, which means (thanks to rust-lang/rust#128537) that it will automatically be passed as an immediate in LLVM. The only special-casing we still have is for the extra sanity-checks we add that ensure that the indices are all in-bounds. (And the GCC backend needs to do a bunch of work since the Rust intrinsic is modeled after what LLVM expects, which seems to be quite different from what GCC expects.) Fixes rust-lang/rust#128738, see that issue for more context.
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Since recently, codegen always passes constants of vector type as immediates in LLVM (#128537). This gives us a change to clean up this hack, where the
idxargument ofsimd_shuffleis forced to be passed as an immediate. However, simd_shuffle for some reason actually takes an array as argument, not a vector, so the hack is still required to ensure that the array becomes an immediate (which then later stages of codegen convert into a vector, as that's what LLVM needs).This is more painful than it should be because stdarch is a submodule 😢 , so we'll have to do it in stages:
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