diff options
Diffstat (limited to 'third_party/rust/bindgen/ir/analysis/has_float.rs')
| -rw-r--r-- | third_party/rust/bindgen/ir/analysis/has_float.rs | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/third_party/rust/bindgen/ir/analysis/has_float.rs b/third_party/rust/bindgen/ir/analysis/has_float.rs new file mode 100644 index 0000000000..bbf2126f70 --- /dev/null +++ b/third_party/rust/bindgen/ir/analysis/has_float.rs @@ -0,0 +1,252 @@ +//! Determining which types has float. + +use super::{generate_dependencies, ConstrainResult, MonotoneFramework}; +use crate::ir::comp::Field; +use crate::ir::comp::FieldMethods; +use crate::ir::context::{BindgenContext, ItemId}; +use crate::ir::traversal::EdgeKind; +use crate::ir::ty::TypeKind; +use crate::{HashMap, HashSet}; + +/// An analysis that finds for each IR item whether it has float or not. +/// +/// We use the monotone constraint function `has_float`, +/// defined as follows: +/// +/// * If T is float or complex float, T trivially has. +/// * If T is a type alias, a templated alias or an indirection to another type, +/// it has float if the type T refers to has. +/// * If T is a compound type, it has float if any of base memter or field +/// has. +/// * If T is an instantiation of an abstract template definition, T has +/// float if any of the template arguments or template definition +/// has. +#[derive(Debug, Clone)] +pub struct HasFloat<'ctx> { + ctx: &'ctx BindgenContext, + + // The incremental result of this analysis's computation. Everything in this + // set has float. + has_float: HashSet<ItemId>, + + // Dependencies saying that if a key ItemId has been inserted into the + // `has_float` set, then each of the ids in Vec<ItemId> need to be + // considered again. + // + // This is a subset of the natural IR graph with reversed edges, where we + // only include the edges from the IR graph that can affect whether a type + // has float or not. + dependencies: HashMap<ItemId, Vec<ItemId>>, +} + +impl<'ctx> HasFloat<'ctx> { + fn consider_edge(kind: EdgeKind) -> bool { + match kind { + EdgeKind::BaseMember | + EdgeKind::Field | + EdgeKind::TypeReference | + EdgeKind::VarType | + EdgeKind::TemplateArgument | + EdgeKind::TemplateDeclaration | + EdgeKind::TemplateParameterDefinition => true, + + EdgeKind::Constructor | + EdgeKind::Destructor | + EdgeKind::FunctionReturn | + EdgeKind::FunctionParameter | + EdgeKind::InnerType | + EdgeKind::InnerVar | + EdgeKind::Method => false, + EdgeKind::Generic => false, + } + } + + fn insert<Id: Into<ItemId>>(&mut self, id: Id) -> ConstrainResult { + let id = id.into(); + trace!("inserting {:?} into the has_float set", id); + + let was_not_already_in_set = self.has_float.insert(id); + assert!( + was_not_already_in_set, + "We shouldn't try and insert {:?} twice because if it was \ + already in the set, `constrain` should have exited early.", + id + ); + + ConstrainResult::Changed + } +} + +impl<'ctx> MonotoneFramework for HasFloat<'ctx> { + type Node = ItemId; + type Extra = &'ctx BindgenContext; + type Output = HashSet<ItemId>; + + fn new(ctx: &'ctx BindgenContext) -> HasFloat<'ctx> { + let has_float = HashSet::default(); + let dependencies = generate_dependencies(ctx, Self::consider_edge); + + HasFloat { + ctx, + has_float, + dependencies, + } + } + + fn initial_worklist(&self) -> Vec<ItemId> { + self.ctx.allowlisted_items().iter().cloned().collect() + } + + fn constrain(&mut self, id: ItemId) -> ConstrainResult { + trace!("constrain: {:?}", id); + + if self.has_float.contains(&id) { + trace!(" already know it do not have float"); + return ConstrainResult::Same; + } + + let item = self.ctx.resolve_item(id); + let ty = match item.as_type() { + Some(ty) => ty, + None => { + trace!(" not a type; ignoring"); + return ConstrainResult::Same; + } + }; + + match *ty.kind() { + TypeKind::Void | + TypeKind::NullPtr | + TypeKind::Int(..) | + TypeKind::Function(..) | + TypeKind::Enum(..) | + TypeKind::Reference(..) | + TypeKind::TypeParam | + TypeKind::Opaque | + TypeKind::Pointer(..) | + TypeKind::UnresolvedTypeRef(..) | + TypeKind::ObjCInterface(..) | + TypeKind::ObjCId | + TypeKind::ObjCSel => { + trace!(" simple type that do not have float"); + ConstrainResult::Same + } + + TypeKind::Float(..) | TypeKind::Complex(..) => { + trace!(" float type has float"); + self.insert(id) + } + + TypeKind::Array(t, _) => { + if self.has_float.contains(&t.into()) { + trace!( + " Array with type T that has float also has float" + ); + return self.insert(id); + } + trace!(" Array with type T that do not have float also do not have float"); + ConstrainResult::Same + } + TypeKind::Vector(t, _) => { + if self.has_float.contains(&t.into()) { + trace!( + " Vector with type T that has float also has float" + ); + return self.insert(id); + } + trace!(" Vector with type T that do not have float also do not have float"); + ConstrainResult::Same + } + + TypeKind::ResolvedTypeRef(t) | + TypeKind::TemplateAlias(t, _) | + TypeKind::Alias(t) | + TypeKind::BlockPointer(t) => { + if self.has_float.contains(&t.into()) { + trace!( + " aliases and type refs to T which have float \ + also have float" + ); + self.insert(id) + } else { + trace!(" aliases and type refs to T which do not have float \ + also do not have floaarrayt"); + ConstrainResult::Same + } + } + + TypeKind::Comp(ref info) => { + let bases_have = info + .base_members() + .iter() + .any(|base| self.has_float.contains(&base.ty.into())); + if bases_have { + trace!(" bases have float, so we also have"); + return self.insert(id); + } + let fields_have = info.fields().iter().any(|f| match *f { + Field::DataMember(ref data) => { + self.has_float.contains(&data.ty().into()) + } + Field::Bitfields(ref bfu) => bfu + .bitfields() + .iter() + .any(|b| self.has_float.contains(&b.ty().into())), + }); + if fields_have { + trace!(" fields have float, so we also have"); + return self.insert(id); + } + + trace!(" comp doesn't have float"); + ConstrainResult::Same + } + + TypeKind::TemplateInstantiation(ref template) => { + let args_have = template + .template_arguments() + .iter() + .any(|arg| self.has_float.contains(&arg.into())); + if args_have { + trace!( + " template args have float, so \ + insantiation also has float" + ); + return self.insert(id); + } + + let def_has = self + .has_float + .contains(&template.template_definition().into()); + if def_has { + trace!( + " template definition has float, so \ + insantiation also has" + ); + return self.insert(id); + } + + trace!(" template instantiation do not have float"); + ConstrainResult::Same + } + } + } + + fn each_depending_on<F>(&self, id: ItemId, mut f: F) + where + F: FnMut(ItemId), + { + if let Some(edges) = self.dependencies.get(&id) { + for item in edges { + trace!("enqueue {:?} into worklist", item); + f(*item); + } + } + } +} + +impl<'ctx> From<HasFloat<'ctx>> for HashSet<ItemId> { + fn from(analysis: HasFloat<'ctx>) -> Self { + analysis.has_float + } +} |