Explain LoongArch f16 NaN-boxing in inline asm - #162171
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The psABI leaves the upper bits of a widened f16 value undefined, so the NaN-boxing here isn't ABI-required. It's intentional: it matches LLVM's own codegen and avoids an f16 value being mistaken for a valid f32 value. Update the comment to reflect this.
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…tdev Explain LoongArch f16 NaN-boxing in inline asm The psABI leaves the upper bits of a widened f16 value undefined, so the NaN-boxing here isn't ABI-required. It's intentional: it matches LLVM's own codegen and avoids an f16 value being mistaken for a valid f32 value. Update the comment to reflect this. r? @folkertdev
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…tdev Explain LoongArch f16 NaN-boxing in inline asm The psABI leaves the upper bits of a widened f16 value undefined, so the NaN-boxing here isn't ABI-required. It's intentional: it matches LLVM's own codegen and avoids an f16 value being mistaken for a valid f32 value. Update the comment to reflect this. r? @folkertdev
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…tdev Explain LoongArch f16 NaN-boxing in inline asm The psABI leaves the upper bits of a widened f16 value undefined, so the NaN-boxing here isn't ABI-required. It's intentional: it matches LLVM's own codegen and avoids an f16 value being mistaken for a valid f32 value. Update the comment to reflect this. r? @folkertdev
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…tdev Explain LoongArch f16 NaN-boxing in inline asm The psABI leaves the upper bits of a widened f16 value undefined, so the NaN-boxing here isn't ABI-required. It's intentional: it matches LLVM's own codegen and avoids an f16 value being mistaken for a valid f32 value. Update the comment to reflect this. r? @folkertdev
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…tdev Explain LoongArch f16 NaN-boxing in inline asm The psABI leaves the upper bits of a widened f16 value undefined, so the NaN-boxing here isn't ABI-required. It's intentional: it matches LLVM's own codegen and avoids an f16 value being mistaken for a valid f32 value. Update the comment to reflect this. r? @folkertdev
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…tdev Explain LoongArch f16 NaN-boxing in inline asm The psABI leaves the upper bits of a widened f16 value undefined, so the NaN-boxing here isn't ABI-required. It's intentional: it matches LLVM's own codegen and avoids an f16 value being mistaken for a valid f32 value. Update the comment to reflect this. r? @folkertdev
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…tdev Explain LoongArch f16 NaN-boxing in inline asm The psABI leaves the upper bits of a widened f16 value undefined, so the NaN-boxing here isn't ABI-required. It's intentional: it matches LLVM's own codegen and avoids an f16 value being mistaken for a valid f32 value. Update the comment to reflect this. r? @folkertdev
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…uwer Rollup of 23 pull requests Successful merges: - #162164 (Revert "Implement Debug for C-like enums with a concatenated string") - #160564 (volatile: allow accesses to non-AM memory to trap) - #161579 (suggest calling a fn item used as the iterator of a `for` loop) - #162044 (coverage: Resolve spans to file-coordinates in a separate step) - #162120 (Introduce `PerOwnerLoweringState`) - #162151 (Test itanium mangling of `f16` and `f128`) - #162162 (Don't special-case `!` in stability checks anymore) - #162181 (Remove wrong UnusedBraces lint for iterator loop in edition 2024 ) - #162187 (Rename `thir::ExprKind::Use` to `ValueExpr`) - #158401 (mgca: Don't ICE when evaluating ValTrees that contain error constants) - #159873 (fuchsia: Add safestack as a supported sanitizer for x86_64 fuchsia) - #161847 (Preserve visibility in nested macro import suggestions) - #161972 (Improve tests for `#[track_caller]` in async) - #162008 (Render the `box` pattern removal diagnostic more actionable & remove `box` expression recovery) - #162065 (std: don't reference `libc::O_NOFOLLOW` on VxWorks in `set_perm_nofollow`) - #162076 (docs(num): clarify conditions under which error occurs in `impl TryFrom<int> for int`) - #162152 (Revert "retrieve supported GCC targets from the sysroot") - #162153 (Prefer `LLVMGetVersion` for runtime info) - #162168 (fix ICE in project_goals/inherent) - #162171 (Explain LoongArch f16 NaN-boxing in inline asm) - #162173 (fix supposedly unreachable `bug!` being reachable) - #162191 (core: mark float `ClampBounds` methods as `#[inline]`) - #162199 (docs(time): clarify exact seconds for hour and minute)
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…tdev Explain LoongArch f16 NaN-boxing in inline asm The psABI leaves the upper bits of a widened f16 value undefined, so the NaN-boxing here isn't ABI-required. It's intentional: it matches LLVM's own codegen and avoids an f16 value being mistaken for a valid f32 value. Update the comment to reflect this. r? @folkertdev
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Rollup of 23 pull requests Successful merges: - #157808 (sanitizers: Implement support for the sanitize ignorelist) - #160564 (volatile: allow accesses to non-AM memory to trap) - #161579 (suggest calling a fn item used as the iterator of a `for` loop) - #162044 (coverage: Resolve spans to file-coordinates in a separate step) - #162120 (Introduce `PerOwnerLoweringState`) - #162151 (Test itanium mangling of `f16` and `f128`) - #162162 (Don't special-case `!` in stability checks anymore) - #162181 (Remove wrong UnusedBraces lint for iterator loop in edition 2024 ) - #162187 (Rename `thir::ExprKind::Use` to `ValueExpr`) - #158401 (mgca: Don't ICE when evaluating ValTrees that contain error constants) - #159873 (fuchsia: Add safestack as a supported sanitizer for x86_64 fuchsia) - #161847 (Preserve visibility in nested macro import suggestions) - #161972 (Improve tests for `#[track_caller]` in async) - #162008 (Render the `box` pattern removal diagnostic more actionable & remove `box` expression recovery) - #162065 (std: don't reference `libc::O_NOFOLLOW` on VxWorks in `set_perm_nofollow`) - #162076 (docs(num): clarify conditions under which error occurs in `impl TryFrom<int> for int`) - #162152 (Revert "retrieve supported GCC targets from the sysroot") - #162153 (Prefer `LLVMGetVersion` for runtime info) - #162168 (fix ICE in project_goals/inherent) - #162171 (Explain LoongArch f16 NaN-boxing in inline asm) - #162173 (fix supposedly unreachable `bug!` being reachable) - #162191 (core: mark float `ClampBounds` methods as `#[inline]`) - #162199 (docs(time): clarify exact seconds for hour and minute)
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…tdev Explain LoongArch f16 NaN-boxing in inline asm The psABI leaves the upper bits of a widened f16 value undefined, so the NaN-boxing here isn't ABI-required. It's intentional: it matches LLVM's own codegen and avoids an f16 value being mistaken for a valid f32 value. Update the comment to reflect this. r? @folkertdev
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Rollup of 29 pull requests Successful merges: - #161694 (add `Complex` ABI run-make test) - #162014 (Move more `rustdoc-html` tests using `--test` into the right folder) - #162164 (Revert "Implement Debug for C-like enums with a concatenated string") - #160564 (volatile: allow accesses to non-AM memory to trap) - #161579 (suggest calling a fn item used as the iterator of a `for` loop) - #162044 (coverage: Resolve spans to file-coordinates in a separate step) - #162120 (Introduce `PerOwnerLoweringState`) - #162132 (std: improve safety documentation in UNIX stack overflow code) - #162151 (Test itanium mangling of `f16` and `f128`) - #162162 (Don't special-case `!` in stability checks anymore) - #162181 (Remove wrong UnusedBraces lint for iterator loop in edition 2024 ) - #162187 (Rename `thir::ExprKind::Use` to `ValueExpr`) - #158401 (mgca: Don't ICE when evaluating ValTrees that contain error constants) - #159873 (fuchsia: Add safestack as a supported sanitizer for x86_64 fuchsia) - #161847 (Preserve visibility in nested macro import suggestions) - #161951 (Windows: add fallback if `canonicalize` fails) - #161972 (Improve tests for `#[track_caller]` in async) - #162008 (Render the `box` pattern removal diagnostic more actionable & remove `box` expression recovery) - #162065 (std: don't reference `libc::O_NOFOLLOW` on VxWorks in `set_perm_nofollow`) - #162076 (docs(num): clarify conditions under which error occurs in `impl TryFrom<int> for int`) - #162152 (Revert "retrieve supported GCC targets from the sysroot") - #162153 (Prefer `LLVMGetVersion` for runtime info) - #162168 (fix ICE in project_goals/inherent) - #162171 (Explain LoongArch f16 NaN-boxing in inline asm) - #162173 (fix supposedly unreachable `bug!` being reachable) - #162180 (remove outdated next-solver FIXMEs) - #162191 (core: mark float `ClampBounds` methods as `#[inline]`) - #162195 (docs(time): clarify exact seconds for week and day) - #162199 (docs(time): clarify exact seconds for hour and minute)
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…uwer Rollup of 25 pull requests Successful merges: - #161694 (add `Complex` ABI run-make test) - #162014 (Move more `rustdoc-html` tests using `--test` into the right folder) - #162164 (Revert "Implement Debug for C-like enums with a concatenated string") - #160564 (volatile: allow accesses to non-AM memory to trap) - #161579 (suggest calling a fn item used as the iterator of a `for` loop) - #162044 (coverage: Resolve spans to file-coordinates in a separate step) - #162120 (Introduce `PerOwnerLoweringState`) - #162132 (std: improve safety documentation in UNIX stack overflow code) - #162151 (Test itanium mangling of `f16` and `f128`) - #162162 (Don't special-case `!` in stability checks anymore) - #162181 (Remove wrong UnusedBraces lint for iterator loop in edition 2024 ) - #162187 (Rename `thir::ExprKind::Use` to `ValueExpr`) - #158401 (mgca: Don't ICE when evaluating ValTrees that contain error constants) - #159873 (fuchsia: Add safestack as a supported sanitizer for x86_64 fuchsia) - #161135 (Add `f16` and `f128` inline ASM support for PowerPC) - #161847 (Preserve visibility in nested macro import suggestions) - #161972 (Improve tests for `#[track_caller]` in async) - #162008 (Render the `box` pattern removal diagnostic more actionable & remove `box` expression recovery) - #162065 (std: don't reference `libc::O_NOFOLLOW` on VxWorks in `set_perm_nofollow`) - #162076 (docs(num): clarify conditions under which error occurs in `impl TryFrom<int> for int`) - #162111 (Update mailmap for Will Crichton and Petr Hosek) - #162152 (Revert "retrieve supported GCC targets from the sysroot") - #162153 (Prefer `LLVMGetVersion` for runtime info) - #162168 (fix ICE in project_goals/inherent) - #162171 (Explain LoongArch f16 NaN-boxing in inline asm)
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Rollup merge of #162171 - heiher:loong-f16-nan-box, r=folkertdev Explain LoongArch f16 NaN-boxing in inline asm The psABI leaves the upper bits of a widened f16 value undefined, so the NaN-boxing here isn't ABI-required. It's intentional: it matches LLVM's own codegen and avoids an f16 value being mistaken for a valid f32 value. Update the comment to reflect this. r? @folkertdev
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Note This PR was benchmarked as part of triage of its containing rollup: triage URL. Finished benchmarking commit (7eecd28): comparison URL. Overall result: no relevant changes - no action needed@rustbot label: -perf-regression Instruction countThis perf run didn't have relevant results for this metric. Max RSS (memory usage)This perf run didn't have relevant results for this metric. CyclesThis perf run didn't have relevant results for this metric. Binary sizeThis perf run didn't have relevant results for this metric. Bootstrap: missing data |
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…uwer Rollup of 25 pull requests Successful merges: - rust-lang/rust#161694 (add `Complex` ABI run-make test) - rust-lang/rust#162014 (Move more `rustdoc-html` tests using `--test` into the right folder) - rust-lang/rust#162164 (Revert "Implement Debug for C-like enums with a concatenated string") - rust-lang/rust#160564 (volatile: allow accesses to non-AM memory to trap) - rust-lang/rust#161579 (suggest calling a fn item used as the iterator of a `for` loop) - rust-lang/rust#162044 (coverage: Resolve spans to file-coordinates in a separate step) - rust-lang/rust#162120 (Introduce `PerOwnerLoweringState`) - rust-lang/rust#162132 (std: improve safety documentation in UNIX stack overflow code) - rust-lang/rust#162151 (Test itanium mangling of `f16` and `f128`) - rust-lang/rust#162162 (Don't special-case `!` in stability checks anymore) - rust-lang/rust#162181 (Remove wrong UnusedBraces lint for iterator loop in edition 2024 ) - rust-lang/rust#162187 (Rename `thir::ExprKind::Use` to `ValueExpr`) - rust-lang/rust#158401 (mgca: Don't ICE when evaluating ValTrees that contain error constants) - rust-lang/rust#159873 (fuchsia: Add safestack as a supported sanitizer for x86_64 fuchsia) - rust-lang/rust#161135 (Add `f16` and `f128` inline ASM support for PowerPC) - rust-lang/rust#161847 (Preserve visibility in nested macro import suggestions) - rust-lang/rust#161972 (Improve tests for `#[track_caller]` in async) - rust-lang/rust#162008 (Render the `box` pattern removal diagnostic more actionable & remove `box` expression recovery) - rust-lang/rust#162065 (std: don't reference `libc::O_NOFOLLOW` on VxWorks in `set_perm_nofollow`) - rust-lang/rust#162076 (docs(num): clarify conditions under which error occurs in `impl TryFrom<int> for int`) - rust-lang/rust#162111 (Update mailmap for Will Crichton and Petr Hosek) - rust-lang/rust#162152 (Revert "retrieve supported GCC targets from the sysroot") - rust-lang/rust#162153 (Prefer `LLVMGetVersion` for runtime info) - rust-lang/rust#162168 (fix ICE in project_goals/inherent) - rust-lang/rust#162171 (Explain LoongArch f16 NaN-boxing in inline asm)
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The psABI leaves the upper bits of a widened f16 value undefined, so the NaN-boxing here isn't ABI-required. It's intentional: it matches LLVM's own codegen and avoids an f16 value being mistaken for a valid f32 value. Update the comment to reflect this.
r? @folkertdev