cleanup: remove support for 3DNow! cpu features #127864
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r? @wesleywiser rustbot has assigned @wesleywiser. Use |
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These commits modify compiler targets. Some changes occurred in compiler/rustc_codegen_gcc |
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I think you are missing "were removed" or something like that in the first sentence of the description (and commit message). |
whoops, good catch. Thanks! |
antoyo
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Jul 17, 2024
| "llvm.ve.vl.xorm.MMM" => "__builtin_ve_vl_xorm_MMM", | ||
| "llvm.ve.vl.xorm.mmm" => "__builtin_ve_vl_xorm_mmm", | ||
| // x86 | ||
| "llvm.x86.3dnow.pavgusb" => "__builtin_ia32_pavgusb", |
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This file is auto-generated, so it doesn't make sense to remove these.
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Shucks, just noticed it's in the GCC backend too. I'll undo that.
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You should squash this so the commit history still doesn't touch an autogenerated file (twice) |
In llvm/llvm-project@f0eb558 all support for 3DNow! intrinsics and instructions were removed. Per the commit message there, only AMD chips between 1998 and 2011 or so actually supported these instructions, and they were effectively replaced by SSE which was available on many more chips. I'd be very surprised if anyone had ever used these from Rust.
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@bors r+ rollup |
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@rustbot ping rfl I think rfl will need to also adjust this here: https://github.com/Rust-for-Linux/linux/blob/b1263411112305acf2af728728591465becb45b0/scripts/generate_rust_target.rs#L165 Or alternatively tell us that adding |
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Rollup of 7 pull requests Successful merges: - rust-lang#127491 (Migrate 8 very similar FFI `run-make` tests to rmake) - rust-lang#127687 (Const-to-pattern-to-MIR cleanup) - rust-lang#127822 (Migrate `issue-85401-static-mir`, `missing-crate-dependency` and `unstable-flag-required` `run-make` tests to rmake) - rust-lang#127842 (Remove `TrailingToken`.) - rust-lang#127864 (cleanup: remove support for 3DNow! cpu features) - rust-lang#127899 (Mark myself as on leave) - rust-lang#127901 (Add missing GHA group for building `llvm-bitcode-linker`) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of rust-lang#127864 - durin42:farewell-3dnow, r=nikic cleanup: remove support for 3DNow! cpu features In llvm/llvm-project@f0eb558 all support for 3DNow! intrinsics and instructions were removed. Per the commit message there, only AMD chips between 1998 and 2011 or so actually supported these instructions, and they were effectively replaced by SSE which was available on many more chips. I'd be very surprised if anyone had ever used these from Rust. `@rustbot` label: +llvm-main
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LLVM 19 is dropping support for 3DNow! in commit f0eb5587ceeb ("Remove
support for 3DNow!, both intrinsics and builtins. (#96246)"):
Remove support for 3DNow!, both intrinsics and builtins. (#96246)
This set of instructions was only supported by AMD chips starting in
the K6-2 (introduced 1998), and before the "Bulldozer" family
(2011). They were never much used, as they were effectively superseded
by the more-widely-implemented SSE (first implemented on the AMD side
in Athlon XP in 2001).
This is being done as a predecessor towards general removal of MMX
register usage. Since there is almost no usage of the 3DNow!
intrinsics, and no modern hardware even implements them, simple
removal seems like the best option.
Thus we should avoid passing these to the backend, since otherwise we
get a diagnostic about it:
'-3dnow' is not a recognized feature for this target (ignoring feature)
'-3dnowa' is not a recognized feature for this target (ignoring feature)
We could try to disable them only up to LLVM 19 (not the C side one,
but the one used by `rustc`, which may be built with a range of
LLVMs). However, to avoid more complexity, we can likely just remove
them altogether. According to Nikita [2]:
> I don't think it's needed because LLVM should not generate 3dnow
instructions unless specifically asked to, using intrinsics that Rust
does not provide in the first place.
Thus do so, like Rust did for one of their builtin targets [3].
For those curious: Clang will warn only about trying to enable them
(`-m3dnow{,a}`), but not about disabling them (`-mno-3dnow{,a}`), so
there is no change needed there.
Cc: Nikita Popov <github@npopov.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: x86@kernel.org
Link: llvm/llvm-project@f0eb558 [1]
Link: rust-lang/rust#127864 (comment) [2]
Link: rust-lang/rust#127864 [3]
Closes: Rust-for-Linux#1094
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
intel-lab-lkp
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Aug 6, 2024
LLVM 19 is dropping support for 3DNow! in commit f0eb5587ceeb ("Remove
support for 3DNow!, both intrinsics and builtins. (#96246)"):
Remove support for 3DNow!, both intrinsics and builtins. (#96246)
This set of instructions was only supported by AMD chips starting in
the K6-2 (introduced 1998), and before the "Bulldozer" family
(2011). They were never much used, as they were effectively superseded
by the more-widely-implemented SSE (first implemented on the AMD side
in Athlon XP in 2001).
This is being done as a predecessor towards general removal of MMX
register usage. Since there is almost no usage of the 3DNow!
intrinsics, and no modern hardware even implements them, simple
removal seems like the best option.
Thus we should avoid passing these to the backend, since otherwise we
get a diagnostic about it:
'-3dnow' is not a recognized feature for this target (ignoring feature)
'-3dnowa' is not a recognized feature for this target (ignoring feature)
We could try to disable them only up to LLVM 19 (not the C side one,
but the one used by `rustc`, which may be built with a range of
LLVMs). However, to avoid more complexity, we can likely just remove
them altogether. According to Nikita [2]:
> I don't think it's needed because LLVM should not generate 3dnow
instructions unless specifically asked to, using intrinsics that Rust
does not provide in the first place.
Thus do so, like Rust did for one of their builtin targets [3].
For those curious: Clang will warn only about trying to enable them
(`-m3dnow{,a}`), but not about disabling them (`-mno-3dnow{,a}`), so
there is no change needed there.
Cc: Nikita Popov <github@npopov.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: x86@kernel.org
Link: llvm/llvm-project@f0eb558 [1]
Link: rust-lang/rust#127864 (comment) [2]
Link: rust-lang/rust#127864 [3]
Closes: Rust-for-Linux#1094
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
ojeda
added a commit
to Rust-for-Linux/linux
that referenced
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Aug 9, 2024
LLVM 19 is dropping support for 3DNow! in commit f0eb5587ceeb ("Remove
support for 3DNow!, both intrinsics and builtins. (#96246)"):
Remove support for 3DNow!, both intrinsics and builtins. (#96246)
This set of instructions was only supported by AMD chips starting in
the K6-2 (introduced 1998), and before the "Bulldozer" family
(2011). They were never much used, as they were effectively superseded
by the more-widely-implemented SSE (first implemented on the AMD side
in Athlon XP in 2001).
This is being done as a predecessor towards general removal of MMX
register usage. Since there is almost no usage of the 3DNow!
intrinsics, and no modern hardware even implements them, simple
removal seems like the best option.
Thus we should avoid passing these to the backend, since otherwise we
get a diagnostic about it:
'-3dnow' is not a recognized feature for this target (ignoring feature)
'-3dnowa' is not a recognized feature for this target (ignoring feature)
We could try to disable them only up to LLVM 19 (not the C side one,
but the one used by `rustc`, which may be built with a range of
LLVMs). However, to avoid more complexity, we can likely just remove
them altogether. According to Nikita [2]:
> I don't think it's needed because LLVM should not generate 3dnow
> instructions unless specifically asked to, using intrinsics that
> Rust does not provide in the first place.
Thus do so, like Rust did for one of their builtin targets [3].
For those curious: Clang will warn only about trying to enable them
(`-m3dnow{,a}`), but not about disabling them (`-mno-3dnow{,a}`), so
there is no change needed there.
Cc: Nikita Popov <github@npopov.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: x86@kernel.org
Link: llvm/llvm-project@f0eb558 [1]
Link: rust-lang/rust#127864 (comment) [2]
Link: rust-lang/rust#127864 [3]
Closes: #1094
Tested-by: Benno Lossin <benno.lossin@proton.me>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240806144558.114461-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
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In llvm/llvm-project@f0eb558 all support for 3DNow! intrinsics and instructions were removed. Per the commit message there, only AMD chips between 1998 and 2011 or so actually supported these instructions, and they were effectively replaced by SSE which was available on many more chips. I'd be very surprised if anyone had ever used these from Rust.
@rustbot label: +llvm-main