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Rust support for nontemporal stores? #114
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Ah yeah I believe we'll need to add support upstream for such an intrinsic, I don't think we can do this with rustc as-is today |
I've opened up an upstream PR to add this support to rustc |
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alexcrichton
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This commit adds compiler support for two basic operations needed for binding SIMD on x86 platforms: * First, a `nontemporal_store` intrinsic was added for the `_mm_stream_ps`, seen in rust-lang/stdarch#114. This was relatively straightforward and is quite similar to the volatile store intrinsic. * Next, and much more intrusively, a new type to the backend was added. The `x86_mmx` type is used in LLVM for a 64-bit vector register and is used in various intrinsics like `_mm_abs_pi8` as seen in rust-lang/stdarch#74. This new type was added as a new layout option as well as having support added to the trans backend. The type is enabled with the `#[repr(x86_mmx)]` attribute which is intended to just be an implementation detail of SIMD in Rust. I'm not 100% certain about how the `x86_mmx` type was added, so any extra eyes or thoughts on that would be greatly appreciated!
bors
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Nov 22, 2017
rustc: Add support for some more x86 SIMD ops This commit adds compiler support for two basic operations needed for binding SIMD on x86 platforms: * First, a `nontemporal_store` intrinsic was added for the `_mm_stream_ps`, seen in rust-lang/stdarch#114. This was relatively straightforward and is quite similar to the volatile store intrinsic. * Next, and much more intrusively, a new type to the backend was added. The `x86_mmx` type is used in LLVM for a 64-bit vector register and is used in various intrinsics like `_mm_abs_pi8` as seen in rust-lang/stdarch#74. This new type was added as a new layout option as well as having support added to the trans backend. The type is enabled with the `#[repr(x86_mmx)]` attribute which is intended to just be an implementation detail of SIMD in Rust. I'm not 100% certain about how the `x86_mmx` type was added, so any extra eyes or thoughts on that would be greatly appreciated!
alexcrichton
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Nov 25, 2017
This commit adds compiler support for two basic operations needed for binding SIMD on x86 platforms: * First, a `nontemporal_store` intrinsic was added for the `_mm_stream_ps`, seen in rust-lang/stdarch#114. This was relatively straightforward and is quite similar to the volatile store intrinsic. * Next, and much more intrusively, a new type to the backend was added. The `x86_mmx` type is used in LLVM for a 64-bit vector register and is used in various intrinsics like `_mm_abs_pi8` as seen in rust-lang/stdarch#74. This new type was added as a new layout option as well as having support added to the trans backend. The type is enabled with the `#[repr(x86_mmx)]` attribute which is intended to just be an implementation detail of SIMD in Rust. I'm not 100% certain about how the `x86_mmx` type was added, so any extra eyes or thoughts on that would be greatly appreciated!
bors
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Nov 25, 2017
rustc: Add support for some more x86 SIMD ops This commit adds compiler support for two basic operations needed for binding SIMD on x86 platforms: * First, a `nontemporal_store` intrinsic was added for the `_mm_stream_ps`, seen in rust-lang/stdarch#114. This was relatively straightforward and is quite similar to the volatile store intrinsic. * Next, and much more intrusively, a new type to the backend was added. The `x86_mmx` type is used in LLVM for a 64-bit vector register and is used in various intrinsics like `_mm_abs_pi8` as seen in rust-lang/stdarch#74. This new type was added as a new layout option as well as having support added to the trans backend. The type is enabled with the `#[repr(x86_mmx)]` attribute which is intended to just be an implementation detail of SIMD in Rust. I'm not 100% certain about how the `x86_mmx` type was added, so any extra eyes or thoughts on that would be greatly appreciated!
Ok! Took awhile but the support is now upstream as an unstable intrinsic! |
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The
_mm_stream_ps
intrinsic implements a store to memory with a "non-temporal" hint (i.e., try not to pollute the cache). In the LLVM code this is implemented via__builtin_nontemporal_store
which should compile to an LLIRstore
instruction with hint!nontemporal
. e.g., something like:Is there a way to generate this in Rust, or do we need add this to the compiler first?
See also:
store
instruction docsThe text was updated successfully, but these errors were encountered: