diff --git a/library/compiler-builtins/libm/Cargo.toml b/library/compiler-builtins/libm/Cargo.toml index 99bfdbfdc859..72b6dcd5e8e1 100644 --- a/library/compiler-builtins/libm/Cargo.toml +++ b/library/compiler-builtins/libm/Cargo.toml @@ -28,11 +28,13 @@ resolver = "2" members = [ "crates/compiler-builtins-smoke-test", "crates/libm-bench", + "crates/libm-macros", "crates/libm-test", "crates/musl-math-sys", ] default-members = [ ".", + "crates/libm-macros", "crates/libm-test", ] diff --git a/library/compiler-builtins/libm/crates/libm-macros/Cargo.toml b/library/compiler-builtins/libm/crates/libm-macros/Cargo.toml new file mode 100644 index 000000000000..9d2b08e2d78f --- /dev/null +++ b/library/compiler-builtins/libm/crates/libm-macros/Cargo.toml @@ -0,0 +1,12 @@ +[package] +name = "libm-macros" +version = "0.1.0" +edition = "2021" + +[lib] +proc-macro = true + +[dependencies] +proc-macro2 = "1.0.88" +quote = "1.0.37" +syn = { version = "2.0.79", features = ["full", "extra-traits", "visit-mut"] } diff --git a/library/compiler-builtins/libm/crates/libm-macros/src/lib.rs b/library/compiler-builtins/libm/crates/libm-macros/src/lib.rs new file mode 100644 index 000000000000..dc78598ca761 --- /dev/null +++ b/library/compiler-builtins/libm/crates/libm-macros/src/lib.rs @@ -0,0 +1,541 @@ +mod parse; +use std::sync::LazyLock; + +use parse::{Invocation, StructuredInput}; +use proc_macro as pm; +use proc_macro2::{self as pm2, Span}; +use quote::{ToTokens, quote}; +use syn::Ident; +use syn::visit_mut::VisitMut; + +const ALL_FUNCTIONS: &[(Signature, Option, &[&str])] = &[ + ( + // `fn(f32) -> f32` + Signature { args: &[Ty::F32], returns: &[Ty::F32] }, + None, + &[ + "acosf", "acoshf", "asinf", "asinhf", "atanf", "atanhf", "cbrtf", "ceilf", "cosf", + "coshf", "erff", "exp10f", "exp2f", "expf", "expm1f", "fabsf", "floorf", "j0f", "j1f", + "lgammaf", "log10f", "log1pf", "log2f", "logf", "rintf", "roundf", "sinf", "sinhf", + "sqrtf", "tanf", "tanhf", "tgammaf", "truncf", + ], + ), + ( + // `(f64) -> f64` + Signature { args: &[Ty::F64], returns: &[Ty::F64] }, + None, + &[ + "acos", "acosh", "asin", "asinh", "atan", "atanh", "cbrt", "ceil", "cos", "cosh", + "erf", "exp10", "exp2", "exp", "expm1", "fabs", "floor", "j0", "j1", "lgamma", "log10", + "log1p", "log2", "log", "rint", "round", "sin", "sinh", "sqrt", "tan", "tanh", + "tgamma", "trunc", + ], + ), + ( + // `(f32, f32) -> f32` + Signature { args: &[Ty::F32, Ty::F32], returns: &[Ty::F32] }, + None, + &[ + "atan2f", + "copysignf", + "fdimf", + "fmaxf", + "fminf", + "fmodf", + "hypotf", + "nextafterf", + "powf", + "remainderf", + ], + ), + ( + // `(f64, f64) -> f64` + Signature { args: &[Ty::F64, Ty::F64], returns: &[Ty::F64] }, + None, + &[ + "atan2", + "copysign", + "fdim", + "fmax", + "fmin", + "fmod", + "hypot", + "nextafter", + "pow", + "remainder", + ], + ), + ( + // `(f32, f32, f32) -> f32` + Signature { args: &[Ty::F32, Ty::F32, Ty::F32], returns: &[Ty::F32] }, + None, + &["fmaf"], + ), + ( + // `(f64, f64, f64) -> f64` + Signature { args: &[Ty::F64, Ty::F64, Ty::F64], returns: &[Ty::F64] }, + None, + &["fma"], + ), + ( + // `(f32) -> i32` + Signature { args: &[Ty::F32], returns: &[Ty::I32] }, + None, + &["ilogbf"], + ), + ( + // `(f64) -> i32` + Signature { args: &[Ty::F64], returns: &[Ty::I32] }, + None, + &["ilogb"], + ), + ( + // `(i32, f32) -> f32` + Signature { args: &[Ty::I32, Ty::F32], returns: &[Ty::F32] }, + None, + &["jnf"], + ), + ( + // `(i32, f64) -> f64` + Signature { args: &[Ty::I32, Ty::F64], returns: &[Ty::F64] }, + None, + &["jn"], + ), + ( + // `(f32, i32) -> f32` + Signature { args: &[Ty::F32, Ty::I32], returns: &[Ty::F32] }, + None, + &["scalbnf", "ldexpf"], + ), + ( + // `(f64, i64) -> f64` + Signature { args: &[Ty::F64, Ty::I32], returns: &[Ty::F64] }, + None, + &["scalbn", "ldexp"], + ), + ( + // `(f32, &mut f32) -> f32` as `(f32) -> (f32, f32)` + Signature { args: &[Ty::F32], returns: &[Ty::F32, Ty::F32] }, + Some(Signature { args: &[Ty::F32, Ty::MutF32], returns: &[Ty::F32] }), + &["modff"], + ), + ( + // `(f64, &mut f64) -> f64` as `(f64) -> (f64, f64)` + Signature { args: &[Ty::F64], returns: &[Ty::F64, Ty::F64] }, + Some(Signature { args: &[Ty::F64, Ty::MutF64], returns: &[Ty::F64] }), + &["modf"], + ), + ( + // `(f32, &mut c_int) -> f32` as `(f32) -> (f32, i32)` + Signature { args: &[Ty::F32], returns: &[Ty::F32, Ty::I32] }, + Some(Signature { args: &[Ty::F32, Ty::MutCInt], returns: &[Ty::F32] }), + &["frexpf", "lgammaf_r"], + ), + ( + // `(f64, &mut c_int) -> f64` as `(f64) -> (f64, i32)` + Signature { args: &[Ty::F64], returns: &[Ty::F64, Ty::I32] }, + Some(Signature { args: &[Ty::F64, Ty::MutCInt], returns: &[Ty::F64] }), + &["frexp", "lgamma_r"], + ), + ( + // `(f32, f32, &mut c_int) -> f32` as `(f32, f32) -> (f32, i32)` + Signature { args: &[Ty::F32, Ty::F32], returns: &[Ty::F32, Ty::I32] }, + Some(Signature { args: &[Ty::F32, Ty::F32, Ty::MutCInt], returns: &[Ty::F32] }), + &["remquof"], + ), + ( + // `(f64, f64, &mut c_int) -> f64` as `(f64, f64) -> (f64, i32)` + Signature { args: &[Ty::F64, Ty::F64], returns: &[Ty::F64, Ty::I32] }, + Some(Signature { args: &[Ty::F64, Ty::F64, Ty::MutCInt], returns: &[Ty::F64] }), + &["remquo"], + ), + ( + // `(f32, &mut f32, &mut f32)` as `(f32) -> (f32, f32)` + Signature { args: &[Ty::F32], returns: &[Ty::F32, Ty::F32] }, + Some(Signature { args: &[Ty::F32, Ty::MutF32, Ty::MutF32], returns: &[] }), + &["sincosf"], + ), + ( + // `(f64, &mut f64, &mut f64)` as `(f64) -> (f64, f64)` + Signature { args: &[Ty::F64], returns: &[Ty::F64, Ty::F64] }, + Some(Signature { args: &[Ty::F64, Ty::MutF64, Ty::MutF64], returns: &[] }), + &["sincos"], + ), +]; + +/// A type used in a function signature. +#[allow(dead_code)] +#[derive(Debug, Clone, Copy)] +enum Ty { + F16, + F32, + F64, + F128, + I32, + CInt, + MutF16, + MutF32, + MutF64, + MutF128, + MutI32, + MutCInt, +} + +impl ToTokens for Ty { + fn to_tokens(&self, tokens: &mut pm2::TokenStream) { + let ts = match self { + Ty::F16 => quote! { f16 }, + Ty::F32 => quote! { f32 }, + Ty::F64 => quote! { f64 }, + Ty::F128 => quote! { f128 }, + Ty::I32 => quote! { i32 }, + Ty::CInt => quote! { ::core::ffi::c_int }, + Ty::MutF16 => quote! { &mut f16 }, + Ty::MutF32 => quote! { &mut f32 }, + Ty::MutF64 => quote! { &mut f64 }, + Ty::MutF128 => quote! { &mut f128 }, + Ty::MutI32 => quote! { &mut i32 }, + Ty::MutCInt => quote! { &mut core::ffi::c_int }, + }; + + tokens.extend(ts); + } +} + +/// Representation of e.g. `(f32, f32) -> f32` +#[derive(Debug, Clone)] +struct Signature { + args: &'static [Ty], + returns: &'static [Ty], +} + +/// Combined information about a function implementation. +#[derive(Debug, Clone)] +struct FunctionInfo { + name: &'static str, + /// Function signature for C implementations + c_sig: Signature, + /// Function signature for Rust implementations + rust_sig: Signature, +} + +/// A flat representation of `ALL_FUNCTIONS`. +static ALL_FUNCTIONS_FLAT: LazyLock> = LazyLock::new(|| { + let mut ret = Vec::new(); + + for (rust_sig, c_sig, names) in ALL_FUNCTIONS { + for name in *names { + let api = FunctionInfo { + name, + rust_sig: rust_sig.clone(), + c_sig: c_sig.clone().unwrap_or_else(|| rust_sig.clone()), + }; + ret.push(api); + } + } + + ret.sort_by_key(|item| item.name); + ret +}); + +/// Do something for each function present in this crate. +/// +/// Takes a callback macro and invokes it multiple times, once for each function that +/// this crate exports. This makes it easy to create generic tests, benchmarks, or other checks +/// and apply it to each symbol. +/// +/// Additionally, the `extra` and `fn_extra` patterns can make use of magic identifiers: +/// +/// - `MACRO_FN_NAME`: gets replaced with the name of the function on that invocation. +/// - `MACRO_FN_NAME_NORMALIZED`: similar to the above, but removes sufixes so e.g. `sinf` becomes +/// `sin`, `cosf128` becomes `cos`, etc. +/// +/// Invoke as: +/// +/// ``` +/// // Macro that is invoked once per function +/// macro_rules! callback_macro { +/// ( +/// // Name of that function +/// fn_name: $fn_name:ident, +/// // Function signature of the C version (e.g. `fn(f32, &mut f32) -> f32`) +/// CFn: $CFn:ty, +/// // A tuple representing the C version's arguments (e.g. `(f32, &mut f32)`) +/// CArgs: $CArgs:ty, +/// // The C version's return type (e.g. `f32`) +/// CRet: $CRet:ty, +/// // Function signature of the Rust version (e.g. `fn(f32) -> (f32, f32)`) +/// RustFn: $RustFn:ty, +/// // A tuple representing the Rust version's arguments (e.g. `(f32,)`) +/// RustArgs: $RustArgs:ty, +/// // The Rust version's return type (e.g. `(f32, f32)`) +/// RustRet: $RustRet:ty, +/// // Attributes for the current function, if any +/// attrs: [$($meta:meta)*] +/// // Extra tokens passed directly (if any) +/// extra: [$extra:ident], +/// // Extra function-tokens passed directly (if any) +/// fn_extra: $fn_extra:expr, +/// ) => { }; +/// } +/// +/// libm_macros::for_each_function! { +/// // The macro to invoke as a callback +/// callback: callback_macro, +/// // Functions to skip, i.e. `callback` shouldn't be called at all for these. +/// // +/// // This is an optional field. +/// skip: [sin, cos], +/// // Attributes passed as `attrs` for specific functions. For example, here the invocation +/// // with `sinf` and that with `cosf` will both get `meta1` and `meta2`, but no others will. +/// // +/// // This is an optional field. +/// attributes: [ +/// #[meta1] +/// #[meta2] +/// [sinf, cosf], +/// ], +/// // Any tokens that should be passed directly to all invocations of the callback. This can +/// // be used to pass local variables or other things the macro needs access to. +/// // +/// // This is an optional field. +/// extra: [foo], +/// // Similar to `extra`, but allow providing a pattern for only specific functions. Uses +/// // a simplified match-like syntax. +/// fn_extra: match MACRO_FN_NAME { +/// hypot | hypotf => |x| x.hypot(), +/// _ => |x| x, +/// }, +/// } +/// ``` +#[proc_macro] +pub fn for_each_function(tokens: pm::TokenStream) -> pm::TokenStream { + let input = syn::parse_macro_input!(tokens as Invocation); + + let res = StructuredInput::from_fields(input) + .and_then(|s_in| validate(&s_in).map(|fn_list| (s_in, fn_list))) + .and_then(|(s_in, fn_list)| expand(s_in, &fn_list)); + + match res { + Ok(ts) => ts.into(), + Err(e) => e.into_compile_error().into(), + } +} + +/// Check for any input that is structurally correct but has other problems. +/// +/// Returns the list of function names that we should expand for. +fn validate(input: &StructuredInput) -> syn::Result> { + // Collect lists of all functions that are provied as macro inputs in various fields (only, + // skip, attributes). + let attr_mentions = input + .attributes + .iter() + .flat_map(|map_list| map_list.iter()) + .flat_map(|attr_map| attr_map.names.iter()); + let only_mentions = input.only.iter().flat_map(|only_list| only_list.iter()); + let fn_extra_mentions = + input.fn_extra.iter().flat_map(|v| v.keys()).filter(|name| *name != "_"); + let all_mentioned_fns = + input.skip.iter().chain(only_mentions).chain(attr_mentions).chain(fn_extra_mentions); + + // Make sure that every function mentioned is a real function + for mentioned in all_mentioned_fns { + if !ALL_FUNCTIONS_FLAT.iter().any(|func| mentioned == func.name) { + let e = syn::Error::new( + mentioned.span(), + format!("unrecognized function name `{mentioned}`"), + ); + return Err(e); + } + } + + if !input.skip.is_empty() && input.only.is_some() { + let e = syn::Error::new( + input.only_span.unwrap(), + format!("only one of `skip` or `only` may be specified"), + ); + return Err(e); + } + + // Construct a list of what we intend to expand + let mut fn_list = Vec::new(); + for func in ALL_FUNCTIONS_FLAT.iter() { + let fn_name = func.name; + // If we have an `only` list and it does _not_ contain this function name, skip it + if input.only.as_ref().is_some_and(|only| !only.iter().any(|o| o == fn_name)) { + continue; + } + + // If there is a `skip` list that contains this function name, skip it + if input.skip.iter().any(|s| s == fn_name) { + continue; + } + + // Run everything else + fn_list.push(func); + } + + if let Some(map) = &input.fn_extra { + if !map.keys().any(|key| key == "_") { + // No default provided; make sure every expected function is covered + let mut fns_not_covered = Vec::new(); + for func in &fn_list { + if !map.keys().any(|key| key == func.name) { + // `name` was not mentioned in the `match` statement + fns_not_covered.push(func); + } + } + + if !fns_not_covered.is_empty() { + let e = syn::Error::new( + input.fn_extra_span.unwrap(), + format!( + "`fn_extra`: no default `_` pattern specified and the following \ + patterns are not covered: {fns_not_covered:#?}" + ), + ); + return Err(e); + } + } + }; + + Ok(fn_list) +} + +/// Expand our structured macro input into invocations of the callback macro. +fn expand(input: StructuredInput, fn_list: &[&FunctionInfo]) -> syn::Result { + let mut out = pm2::TokenStream::new(); + let default_ident = Ident::new("_", Span::call_site()); + let callback = input.callback; + + for func in fn_list { + let fn_name = Ident::new(func.name, Span::call_site()); + + // Prepare attributes in an `attrs: ...` field + let meta_field = match &input.attributes { + Some(attrs) => { + let meta = attrs + .iter() + .filter(|map| map.names.contains(&fn_name)) + .flat_map(|map| &map.meta); + quote! { attrs: [ #( #meta )* ] } + } + None => pm2::TokenStream::new(), + }; + + // Prepare extra in an `extra: ...` field, running the replacer + let extra_field = match input.extra.clone() { + Some(mut extra) => { + let mut v = MacroReplace::new(func.name); + v.visit_expr_mut(&mut extra); + v.finish()?; + + quote! { extra: #extra, } + } + None => pm2::TokenStream::new(), + }; + + // Prepare function-specific extra in a `fn_extra: ...` field, running the replacer + let fn_extra_field = match input.fn_extra { + Some(ref map) => { + let mut fn_extra = + map.get(&fn_name).or_else(|| map.get(&default_ident)).unwrap().clone(); + + let mut v = MacroReplace::new(func.name); + v.visit_expr_mut(&mut fn_extra); + v.finish()?; + + quote! { fn_extra: #fn_extra, } + } + None => pm2::TokenStream::new(), + }; + + let c_args = &func.c_sig.args; + let c_ret = &func.c_sig.returns; + let rust_args = &func.rust_sig.args; + let rust_ret = &func.rust_sig.returns; + + let new = quote! { + #callback! { + fn_name: #fn_name, + CFn: fn( #(#c_args),* ,) -> ( #(#c_ret),* ), + CArgs: ( #(#c_args),* ,), + CRet: ( #(#c_ret),* ), + RustFn: fn( #(#rust_args),* ,) -> ( #(#rust_ret),* ), + RustArgs: ( #(#rust_args),* ,), + RustRet: ( #(#rust_ret),* ), + #meta_field + #extra_field + #fn_extra_field + } + }; + + out.extend(new); + } + + Ok(out) +} + +/// Visitor to replace "magic" identifiers that we allow: `MACRO_FN_NAME` and +/// `MACRO_FN_NAME_NORMALIZED`. +struct MacroReplace { + fn_name: &'static str, + /// Remove the trailing `f` or `f128` to make + norm_name: String, + error: Option, +} + +impl MacroReplace { + fn new(name: &'static str) -> Self { + // Keep this in sync with `libm_test::canonical_name` + let known_mappings = &[ + ("erff", "erf"), + ("erf", "erf"), + ("lgammaf_r", "lgamma_r"), + ("modff", "modf"), + ("modf", "modf"), + ]; + + let norm_name = match known_mappings.iter().find(|known| known.0 == name) { + Some(found) => found.1, + None => name + .strip_suffix("f") + .or_else(|| name.strip_suffix("f16")) + .or_else(|| name.strip_suffix("f128")) + .unwrap_or(name), + }; + + Self { fn_name: name, norm_name: norm_name.to_owned(), error: None } + } + + fn finish(self) -> syn::Result<()> { + match self.error { + Some(e) => Err(e), + None => Ok(()), + } + } + + fn visit_ident_inner(&mut self, i: &mut Ident) { + let s = i.to_string(); + if !s.starts_with("MACRO") || self.error.is_some() { + return; + } + + match s.as_str() { + "MACRO_FN_NAME" => *i = Ident::new(self.fn_name, i.span()), + "MACRO_FN_NAME_NORMALIZED" => *i = Ident::new(&self.norm_name, i.span()), + _ => { + self.error = + Some(syn::Error::new(i.span(), format!("unrecognized meta expression `{s}`"))); + } + } + } +} + +impl VisitMut for MacroReplace { + fn visit_ident_mut(&mut self, i: &mut Ident) { + self.visit_ident_inner(i); + syn::visit_mut::visit_ident_mut(self, i); + } +} diff --git a/library/compiler-builtins/libm/crates/libm-macros/src/parse.rs b/library/compiler-builtins/libm/crates/libm-macros/src/parse.rs new file mode 100644 index 000000000000..ee9bd524bbef --- /dev/null +++ b/library/compiler-builtins/libm/crates/libm-macros/src/parse.rs @@ -0,0 +1,236 @@ +use std::collections::BTreeMap; + +use proc_macro2::Span; +use quote::ToTokens; +use syn::parse::{Parse, ParseStream, Parser}; +use syn::punctuated::Punctuated; +use syn::spanned::Spanned; +use syn::token::Comma; +use syn::{Arm, Attribute, Expr, ExprMatch, Ident, Meta, Token, bracketed}; + +/// The input to our macro; just a list of `field: value` items. +#[derive(Debug)] +pub struct Invocation { + fields: Punctuated, +} + +impl Parse for Invocation { + fn parse(input: ParseStream) -> syn::Result { + Ok(Self { fields: input.parse_terminated(Mapping::parse, Token![,])? }) + } +} + +/// A `key: expression` mapping with nothing else. Basically a simplified `syn::Field`. +#[derive(Debug)] +struct Mapping { + name: Ident, + _sep: Token![:], + expr: Expr, +} + +impl Parse for Mapping { + fn parse(input: ParseStream) -> syn::Result { + Ok(Self { name: input.parse()?, _sep: input.parse()?, expr: input.parse()? }) + } +} + +/// The input provided to our proc macro, after parsing into the form we expect. +#[derive(Debug)] +pub struct StructuredInput { + /// Macro to invoke once per function + pub callback: Ident, + /// Skip these functions + pub skip: Vec, + /// Invoke only for these functions + pub only: Option>, + /// Attributes that get applied to specific functions + pub attributes: Option>, + /// Extra expressions to pass to all invocations of the macro + pub extra: Option, + /// Per-function extra expressions to pass to the macro + pub fn_extra: Option>, + // For diagnostics + pub only_span: Option, + pub fn_extra_span: Option, +} + +impl StructuredInput { + pub fn from_fields(input: Invocation) -> syn::Result { + let mut map: Vec<_> = input.fields.into_iter().collect(); + let cb_expr = expect_field(&mut map, "callback")?; + let skip_expr = expect_field(&mut map, "skip").ok(); + let only_expr = expect_field(&mut map, "only").ok(); + let attr_expr = expect_field(&mut map, "attributes").ok(); + let extra = expect_field(&mut map, "extra").ok(); + let fn_extra = expect_field(&mut map, "fn_extra").ok(); + + if !map.is_empty() { + Err(syn::Error::new( + map.first().unwrap().name.span(), + format!("unexpected fields {map:?}"), + ))?; + } + + let skip = match skip_expr { + Some(expr) => Parser::parse2(parse_ident_array, expr.into_token_stream())?, + None => Vec::new(), + }; + + let only_span = only_expr.as_ref().map(|expr| expr.span()); + let only = match only_expr { + Some(expr) => Some(Parser::parse2(parse_ident_array, expr.into_token_stream())?), + None => None, + }; + + let attributes = match attr_expr { + Some(expr) => { + let mut attributes = Vec::new(); + let attr_exprs = Parser::parse2(parse_expr_array, expr.into_token_stream())?; + + for attr in attr_exprs { + attributes.push(syn::parse2(attr.into_token_stream())?); + } + Some(attributes) + } + None => None, + }; + + let fn_extra_span = fn_extra.as_ref().map(|expr| expr.span()); + let fn_extra = match fn_extra { + Some(expr) => Some(extract_fn_extra_field(expr)?), + None => None, + }; + + Ok(Self { + callback: expect_ident(cb_expr)?, + skip, + only, + only_span, + attributes, + extra, + fn_extra, + fn_extra_span, + }) + } +} + +fn extract_fn_extra_field(expr: Expr) -> syn::Result> { + let Expr::Match(mexpr) = expr else { + let e = syn::Error::new(expr.span(), "`fn_extra` expects a match expression"); + return Err(e); + }; + + let ExprMatch { attrs, match_token: _, expr, brace_token: _, arms } = mexpr; + + expect_empty_attrs(&attrs)?; + + let match_on = expect_ident(*expr)?; + if match_on != "MACRO_FN_NAME" { + let e = syn::Error::new(match_on.span(), "only allowed to match on `MACRO_FN_NAME`"); + return Err(e); + } + + let mut res = BTreeMap::new(); + + for arm in arms { + let Arm { attrs, pat, guard, fat_arrow_token: _, body, comma: _ } = arm; + + expect_empty_attrs(&attrs)?; + + let keys = match pat { + syn::Pat::Wild(w) => vec![Ident::new("_", w.span())], + _ => Parser::parse2(parse_ident_pat, pat.into_token_stream())?, + }; + + if let Some(guard) = guard { + let e = syn::Error::new(guard.0.span(), "no guards allowed in this position"); + return Err(e); + } + + for key in keys { + let inserted = res.insert(key.clone(), *body.clone()); + if inserted.is_some() { + let e = syn::Error::new(key.span(), format!("key `{key}` specified twice")); + return Err(e); + } + } + } + + Ok(res) +} + +fn expect_empty_attrs(attrs: &[Attribute]) -> syn::Result<()> { + if attrs.is_empty() { + return Ok(()); + } + + let e = + syn::Error::new(attrs.first().unwrap().span(), "no attributes allowed in this position"); + Err(e) +} + +/// Extract a named field from a map, raising an error if it doesn't exist. +fn expect_field(v: &mut Vec, name: &str) -> syn::Result { + let pos = v.iter().position(|v| v.name == name).ok_or_else(|| { + syn::Error::new(Span::call_site(), format!("missing expected field `{name}`")) + })?; + + Ok(v.remove(pos).expr) +} + +/// Coerce an expression into a simple identifier. +fn expect_ident(expr: Expr) -> syn::Result { + syn::parse2(expr.into_token_stream()) +} + +/// Parse an array of expressions. +fn parse_expr_array(input: ParseStream) -> syn::Result> { + let content; + let _ = bracketed!(content in input); + let fields = content.parse_terminated(Expr::parse, Token![,])?; + Ok(fields.into_iter().collect()) +} + +/// Parse an array of idents, e.g. `[foo, bar, baz]`. +fn parse_ident_array(input: ParseStream) -> syn::Result> { + let content; + let _ = bracketed!(content in input); + let fields = content.parse_terminated(Ident::parse, Token![,])?; + Ok(fields.into_iter().collect()) +} + +/// Parse an pattern of idents, specifically `(foo | bar | baz)`. +fn parse_ident_pat(input: ParseStream) -> syn::Result> { + if !input.peek2(Token![|]) { + return Ok(vec![input.parse()?]); + } + + let fields = Punctuated::::parse_separated_nonempty(input)?; + Ok(fields.into_iter().collect()) +} + +/// A mapping of attributes to identifiers (just a simplified `Expr`). +/// +/// Expressed as: +/// +/// ```ignore +/// #[meta1] +/// #[meta2] +/// [foo, bar, baz] +/// ``` +#[derive(Debug)] +pub struct AttributeMap { + pub meta: Vec, + pub names: Vec, +} + +impl Parse for AttributeMap { + fn parse(input: ParseStream) -> syn::Result { + let attrs = input.call(Attribute::parse_outer)?; + + Ok(Self { + meta: attrs.into_iter().map(|a| a.meta).collect(), + names: parse_ident_array(input)?, + }) + } +} diff --git a/library/compiler-builtins/libm/crates/libm-macros/tests/basic.rs b/library/compiler-builtins/libm/crates/libm-macros/tests/basic.rs new file mode 100644 index 000000000000..8f8c09f1b64a --- /dev/null +++ b/library/compiler-builtins/libm/crates/libm-macros/tests/basic.rs @@ -0,0 +1,96 @@ +// `STATUS_DLL_NOT_FOUND` on i686 MinGW, not worth looking into. +#![cfg(not(all(target_arch = "x86", target_os = "windows", target_env = "gnu")))] + +macro_rules! basic { + ( + fn_name: $fn_name:ident, + CFn: $CFn:ty, + CArgs: $CArgs:ty, + CRet: $CRet:ty, + RustFn: $RustFn:ty, + RustArgs: $RustArgs:ty, + RustRet: $RustRet:ty, + attrs: [$($meta:meta)*] + extra: [$($extra_tt:tt)*], + fn_extra: $fn_extra:expr, + ) => { + $(#[$meta])* + mod $fn_name { + #[allow(unused)] + type CFnTy = $CFn; + // type CArgsTy<'_> = $CArgs; + // type CRetTy<'_> = $CRet; + #[allow(unused)] + type RustFnTy = $RustFn; + #[allow(unused)] + type RustArgsTy = $RustArgs; + #[allow(unused)] + type RustRetTy = $RustRet; + #[allow(unused)] + const A: &[&str] = &[$($extra_tt)*]; + #[allow(unused)] + fn foo(a: f32) -> f32 { + $fn_extra(a) + } + } + }; +} + +mod test_basic { + libm_macros::for_each_function! { + callback: basic, + skip: [sin, cos], + attributes: [ + // just some random attributes + #[allow(clippy::pedantic)] + #[allow(dead_code)] + [sinf, cosf] + ], + extra: ["foo", "bar"], + fn_extra: match MACRO_FN_NAME { + sin => |x| x + 2.0, + cos | cosf => |x: f32| x.MACRO_FN_NAME_NORMALIZED(), + _ => |_x| 100.0 + } + } +} + +macro_rules! basic_no_extra { + ( + fn_name: $fn_name:ident, + CFn: $CFn:ty, + CArgs: $CArgs:ty, + CRet: $CRet:ty, + RustFn: $RustFn:ty, + RustArgs: $RustArgs:ty, + RustRet: $RustRet:ty, + ) => { + mod $fn_name { + #[allow(unused)] + type CFnTy = $CFn; + // type CArgsTy<'_> = $CArgs; + // type CRetTy<'_> = $CRet; + #[allow(unused)] + type RustFnTy = $RustFn; + #[allow(unused)] + type RustArgsTy = $RustArgs; + #[allow(unused)] + type RustRetTy = $RustRet; + } + }; +} + +mod test_basic_no_extra { + // Test with no extra, no skip, and no attributes + libm_macros::for_each_function! { + callback: basic_no_extra, + } +} + +mod test_only { + // Test that only works + libm_macros::for_each_function! { + callback: basic_no_extra, + only: [sin, sinf], + } +}