rustc_target: Adjust RISC-V feature implication #140139
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This commit adjusts feature implication of the RISC-V ISA for better
feature detection from the user perspective.
The main rule is:
If the feature A is a functional superset of the feature B (A ⊃ B),
A is to imply B, even if this implication is not on the manual.
Such implications (not directly referred in the ISA manual) are commented
as "A ⊃ B" which means "A is a (functional) superset of B".
1. Zbc → Zbkc (add as a superset)
The Zbkc extension is a subset of the Zbc extension
(Zbc - "clmulr" instruction == Zbkc)
2. Zkr → (nothing) (remove dependency to Zicsr)
Implication to the Zicsr extension is removed because (although nearly
harmless), the Zkr extension (or the "seed" CSR section) defines its own
subset of the Zicsr extension.
3. Zvbb → Zvkb (comment as a superset)
This implication was already there but not denoted as a functional
superset. This commit adds the comment.
4. Zvfh → Zvfhmin (comment as a superset)
This is similar to the case above (Zvbb → Zvkb).
5. Zvfh → Zve32f (add implication per the ISA specification)
This dependency is on the ISA manual but was missing (due to the fact
that Zvfh indirectly implies Zve32f on the current implementation
through Zvfh → Zvfhmin, which is a functional relation).
This commit ensures that this is *also* ISA-compliant in the
source code level (there's no functional changes though).
6. Zvknhb → Zvknha (add as a superset)
The Zvknhb extension (SHA-256 / SHA-512) is a functional superset of
the Zvknha extension (SHA-256 only).
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@bors r+ rollup |
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… r=Amanieu
rustc_target: Adjust RISC-V feature implication
This commit adjusts feature implication of the RISC-V ISA for better feature detection from the user perspective.
The main rule is:
* If the feature `A` is a functional superset of the feature `B` (`A ⊃ B`),
`A` is to imply `B`, even if this implication is not on the manual.
Such implications (not directly written in the ISA manual) are commented as `A ⊃ B`
which means "`A` is a (functional) superset of `B`".
1. `Zbc` → `Zbkc` (add as a superset)
The `Zbkc` extension is a subset of the `Zbc` extension (`Zbc` minus `clmulr` instruction).
2. `Zkr` → (nothing) (remove dependency to `Zicsr`)
Implication to the `Zicsr` extension is removed because (although nearly harmless), the `Zkr` extension (or the `seed` CSR section) defines its own subset of the `Zicsr` extension (guaranteed to work against the `seed` CSR which needs read/write access).
3. `Zvbb` → `Zvkb` (comment as a superset)
This implication was already there but not denoted as a functional superset. This commit adds the comment.
4. `Zvfh` → `Zvfhmin` (comment as a superset)
This is similar to the case above (`Zvbb` → `Zvkb`).
5. `Zvfh` → `Zve32f` (add implication per the ISA specification)
This dependency is on the ISA manual but was missing (due to the fact that `Zvfh` indirectly implies `Zve32f` on the current implementation through `Zvfh` → `Zvfhmin` which is a functional relation). This commit ensures that this is *also* ISA-compliant in the source code level (there's no functional changes though).
6. `Zvknhb` → `Zvknha` (add as a superset)
The `Zvknhb` extension (SHA-256 / SHA-512) is a functional superset of the `Zvknha` extension (SHA-256 only).
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Rollup of 23 pull requests Successful merges: - rust-lang#139261 (mitigate MSVC alignment issue on x86-32) - rust-lang#139307 (std: Add performance warnings to HashMap::get_disjoint_mut) - rust-lang#139700 (Autodiff flags) - rust-lang#139752 (set subsections_via_symbols for ld64 helper sections) - rust-lang#139809 (Don't warn about `v128` in wasm ABI transition) - rust-lang#139852 (StableMIR: Implement `CompilerInterface`) - rust-lang#139945 (Extend HIR to track the source and syntax of a lifetime) - rust-lang#140028 (`deref_patterns`: support string and byte string literals in explicit `deref!("...")` patterns) - rust-lang#140139 (rustc_target: Adjust RISC-V feature implication) - rust-lang#140143 (Move `sys::pal::os::Env` into `sys::env`) - rust-lang#140148 (CI: use aws codebuild for job dist-arm-linux) - rust-lang#140150 (fix MAX_EXP and MIN_EXP docs) - rust-lang#140172 (Make algebraic functions into `const fn` items.) - rust-lang#140177 ([compiletest] Parallelize test discovery) - rust-lang#140181 (Remove `synstructure::Structure::underscore_const` calls.) - rust-lang#140184 (Update doc of cygwin target) - rust-lang#140186 (Rename `compute_x` methods) - rust-lang#140187 ([AIX] Handle AIX dynamic library extensions within c-link-to-rust-dylib run-make test) - rust-lang#140191 (Remove git repository from git config) - rust-lang#140194 (minicore: Have `//@ add-core-stubs` also imply `-Cforce-unwind-tables=yes`) - rust-lang#140195 (triagebot: label minicore changes w/ `A-test-infra-minicore` and ping jieyouxu on changes) - rust-lang#140202 (Make #![feature(let_chains)] bootstrap conditional in compiler/) - rust-lang#140214 (Remove comment about handling non-global where bounds with corresponding projection) r? `@ghost` `@rustbot` modify labels: rollup
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…iaskrgr Rollup of 8 pull requests Successful merges: - rust-lang#136083 (Suggest {to,from}_ne_bytes for transmutations between arrays and integers, etc) - rust-lang#138282 (Add `#[repr(u128)]`/`#[repr(i128)]` enums to `improper_ctypes_definitions`) - rust-lang#139700 (Autodiff flags) - rust-lang#140139 (rustc_target: Adjust RISC-V feature implication) - rust-lang#140141 (Move zkVM constants into `sys::env_consts`) - rust-lang#140150 (fix MAX_EXP and MIN_EXP docs) - rust-lang#140172 (Make algebraic functions into `const fn` items.) - rust-lang#140191 (Remove git repository from git config) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of rust-lang#140139 - a4lg:riscv-feature-imply-adjust-1, r=Amanieu rustc_target: Adjust RISC-V feature implication This commit adjusts feature implication of the RISC-V ISA for better feature detection from the user perspective. The main rule is: * If the feature `A` is a functional superset of the feature `B` (`A ⊃ B`), `A` is to imply `B`, even if this implication is not on the manual. Such implications (not directly written in the ISA manual) are commented as `A ⊃ B` which means "`A` is a (functional) superset of `B`". 1. `Zbc` → `Zbkc` (add as a superset) The `Zbkc` extension is a subset of the `Zbc` extension (`Zbc` minus `clmulr` instruction). 2. `Zkr` → (nothing) (remove dependency to `Zicsr`) Implication to the `Zicsr` extension is removed because (although nearly harmless), the `Zkr` extension (or the `seed` CSR section) defines its own subset of the `Zicsr` extension (guaranteed to work against the `seed` CSR which needs read/write access). 3. `Zvbb` → `Zvkb` (comment as a superset) This implication was already there but not denoted as a functional superset. This commit adds the comment. 4. `Zvfh` → `Zvfhmin` (comment as a superset) This is similar to the case above (`Zvbb` → `Zvkb`). 5. `Zvfh` → `Zve32f` (add implication per the ISA specification) This dependency is on the ISA manual but was missing (due to the fact that `Zvfh` indirectly implies `Zve32f` on the current implementation through `Zvfh` → `Zvfhmin` which is a functional relation). This commit ensures that this is *also* ISA-compliant in the source code level (there's no functional changes though). 6. `Zvknhb` → `Zvknha` (add as a superset) The `Zvknhb` extension (SHA-256 / SHA-512) is a functional superset of the `Zvknha` extension (SHA-256 only).
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This commit adjusts feature implication of the RISC-V ISA for better feature detection from the user perspective.
The main rule is:
Ais a functional superset of the featureB(A ⊃ B),Ais to implyB, even if this implication is not on the manual.Such implications (not directly written in the ISA manual) are commented as
A ⊃ Bwhich means "
Ais a (functional) superset ofB".Zbc→Zbkc(add as a superset)The
Zbkcextension is a subset of theZbcextension (Zbcminusclmulrinstruction).Zkr→ (nothing) (remove dependency toZicsr)Implication to the
Zicsrextension is removed because (although nearly harmless), theZkrextension (or theseedCSR section) defines its own subset of theZicsrextension (guaranteed to work against theseedCSR which needs read/write access).Zvbb→Zvkb(comment as a superset)This implication was already there but not denoted as a functional superset. This commit adds the comment.
Zvfh→Zvfhmin(comment as a superset)This is similar to the case above (
Zvbb→Zvkb).Zvfh→Zve32f(add implication per the ISA specification)This dependency is on the ISA manual but was missing (due to the fact that
Zvfhindirectly impliesZve32fon the current implementation throughZvfh→Zvfhminwhich is a functional relation). This commit ensures that this is also ISA-compliant in the source code level (there's no functional changes though).Zvknhb→Zvknha(add as a superset)The
Zvknhbextension (SHA-256 / SHA-512) is a functional superset of theZvknhaextension (SHA-256 only).Related:
#[target_feature]#44839(
riscv_target_feature)riscv_hwprobe-based feature detection on Linux / Android stdarch#1770(synchronized with
stdarch's latest RISC-V implication logic)@rustbot r? @Amanieu
@rustbot label +T-compiler +O-riscv +A-target-feature