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Signed-off-by: Raul Estrada <raulestradaa@gmail.com>
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…120 libm exports (#1660) ## What This PR Does Implements `#1224` across the 9-commit `libdevice_math` series (`#1638`, `#1645`, `#1646`, `#1649`, `#1650`, `#1651`, `#1652`, `#1653`, `#1660`), replacing hand-maintained math dispatch tables across three crates with a single generated table backed by `libdevice.10.bc` evidence and expanding `libm 0.2.16` coverage from 72 to **120 of 124 `f32`/`f64` exports**: 1. **Add `intrinsics/overlay/libdevice_math.toml` + `libdevice.10.bc` signature verification and generate `dialect-mir` math dispatch (`cuda-intrinsics-gen`, `dialect-mir`, `mir-importer`, `rustc-codegen-cuda`)** 2. **Extract float-math lowering into `mir-lower/src/convert/ops/float_math.rs` driven by generated `RustFloatMathLowering` (`mir-lower`)** 3. **Lower scalar aliases (`tgamma`, `ilogb`, `ldexp`, `erf`, `j0`, `y0`, ...), entry-block out-parameter adapters (`frexp`, `modf`, `remquo`), `lgamma_r`, C23 `fmaximum`/`fminimum`, and `j1` (`mir-lower`, `examples/math_special`)** --- ### 1. Generated `libm -> libdevice` Dispatch (`#1224`) Previously, wiring a single `libm` or `std::sys::cmath` function required hand-editing ~10 sites across `rustc-codegen-cuda/src/collector.rs`, `mir-importer`, `dialect-mir`, and `mir-lower`: ```text BEFORE (hand-maintained across 4 crates): collector.rs ──► hardcoded `std::sys::cmath::*` match list mir-importer ──► hand-written `RustFloatMathIntrinsic` enum + `from_core_path` / `from_libm_path` dialect-mir ──► hand-written `CALLEE_*` constants + `is_libdevice_backed_placeholder` mir-lower ──► hand-written placeholder -> `__nv_*` match table AFTER (`intrinsics/overlay/libdevice_math.toml` -> `cuda-intrinsics-gen`): libdevice_math.toml + cuda-13.0.json (102 signatures verified against libdevice.10.bc) │ ▼ crates/dialect-mir/src/generated/libdevice_math.rs ├──► collector.rs `is_intrinsic_lowered_cmath_shim(fn_path)` ├──► mir-importer `from_core_path` + `from_libm_path` -> `CALLEE_*` ├──► codegen `link_requirement()` -> `MathLink::{Always, Libnvvm, Never}` └──► mir-lower `RustFloatMathIntrinsic::lowering(self) -> RustFloatMathLowering` ``` --- ### 2. Entry-Block Out-Parameter Adapters & IEEE Edge-Case Lowerings (`mir-lower`) ```text Function Family Lowering in `mir-lower/src/convert/ops/float_math.rs` ───────────────────────────── ────────────────────────────────────────────────────────────────────────── `frexp`, `modf`, `remquo` Hoists `llvm.alloca` to function entry block (`0` `.local` traffic after `opt -O2` SROA); normalizes `frexp(+-inf/NaN) -> (x, 0)` and `remquo` NaN -> `quo = 0` `lgamma_r`, `lgammaf_r` Composes `__nv_lgamma`, `__nv_floor`, and `__nv_fmod(floor(x), 2.0)` with `-0.0 -> (+inf, -1)`, negative integer poles `-> (+inf, +1)`, `-inf -> (+inf, +1)` C23 `fmaximum*` / `fminimum*` Pure LLVM `fcmp` (empty fast-math flags) + sign-bit tie-break (`-0.0 < +0.0`) `j1`, `j1f` Calls `__nv_j1{,f}` and normalizes `|x| == inf -> +0.0` ``` --- ## Verification * **RTX 5090 (`sm_120a`) GPU Execution & Sanitizer**: * `cargo oxide run math_special`: **2,822 / 2,822 `f32` and `f64` checks PASS** (`compute-sanitizer --tool memcheck`: `0 errors`, `0` `.local` instructions emitted for `frexp`, `modf`, `remquo`, `lgamma_r`, and C23 `minmax`). * `cargo oxide run libm_math` & `cargo oxide run libdevice_math`: **PASS**. * **Generator & Bitcode Verification**: * `cargo run -p cuda-intrinsics-gen -- check` & `verify-libdevice`: **PASS** (`102` `libdevice.10.bc` signatures verified). * **Tests, Lints & Guards**: * `cargo test -p cuda-intrinsics-gen -p dialect-mir -p mir-importer -p mir-lower -p cuda-oxide-codegen --all-targets`: **3,494 tests PASS** * `just fmt-check`, `just clippy`, `scripts/sync-example-locks.sh --check`, and all 18 `scripts/check-*.sh` guards: **all PASS** Closes #1224 --------- Signed-off-by: Raul Estrada <raulestradaa@gmail.com> Signed-off-by: nihalpasham <nihalp@nvidia.com> Co-authored-by: nihalpasham <nihalp@nvidia.com>
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Summary
Add missing f32/f64 libdevice mappings for
tgamma,ilogbandldexp, includingscalbnaliases and standard-librarygamma()shims. This covers the scalar additions in the first stage of #1224 and verifies both integer-result and integer-argument signatures before the table-generation work.Refs #1224.
Changes
scalbn/scalbnfto the correspondingldexplibdevice functions.std::sys::cmath::tgamma{f}shims through the collector.ilogbreturnsi32, andldexptakes ani32exponent.math_special, checking libm and standard-library gamma, integer logarithms, scaling and a user-function control across both precisions.frexpand the generated math tables will follow in separate PRs.Testing
Validated on
sm_120awith the pinned Rust 1.99.1 toolchain.just checkpasses fromcuda-oxide/.math_specialpasses with--all-targets -- -D warnings.cargo oxide run math_specialpasses.libm_mathandmath_hyperbolicpass.Checklist
git commit -s)just -f cuda-oxide/Justfile checkpasses (the local mirror of CI: fmt, clippy, tests, guards, docs)cargo oxide run <example>passes, orcuda-oxide/scripts/smoketest.sh -o '^<example>$'