| //! This module contains `HashStable` implementations for various data types |
| //! from libsyntax in no particular order. |
| |
| use crate::ich::StableHashingContext; |
| |
| use rustc_data_structures::stable_hasher::{HashStable, StableHasher}; |
| use rustc_hir::def_id::{CrateNum, DefId, CRATE_DEF_INDEX}; |
| use rustc_span::SourceFile; |
| use syntax::ast; |
| |
| use smallvec::SmallVec; |
| |
| impl<'ctx> rustc_target::HashStableContext for StableHashingContext<'ctx> {} |
| |
| impl<'a> HashStable<StableHashingContext<'a>> for ast::Lifetime { |
| fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) { |
| self.id.hash_stable(hcx, hasher); |
| self.ident.hash_stable(hcx, hasher); |
| } |
| } |
| |
| impl<'a> HashStable<StableHashingContext<'a>> for [ast::Attribute] { |
| fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) { |
| if self.len() == 0 { |
| self.len().hash_stable(hcx, hasher); |
| return; |
| } |
| |
| // Some attributes are always ignored during hashing. |
| let filtered: SmallVec<[&ast::Attribute; 8]> = self |
| .iter() |
| .filter(|attr| { |
| !attr.is_doc_comment() |
| && !attr.ident().map_or(false, |ident| hcx.is_ignored_attr(ident.name)) |
| }) |
| .collect(); |
| |
| filtered.len().hash_stable(hcx, hasher); |
| for attr in filtered { |
| attr.hash_stable(hcx, hasher); |
| } |
| } |
| } |
| |
| impl<'ctx> syntax::HashStableContext for StableHashingContext<'ctx> { |
| fn hash_attr(&mut self, attr: &ast::Attribute, hasher: &mut StableHasher) { |
| // Make sure that these have been filtered out. |
| debug_assert!(!attr.ident().map_or(false, |ident| self.is_ignored_attr(ident.name))); |
| debug_assert!(!attr.is_doc_comment()); |
| |
| let ast::Attribute { kind, id: _, style, span } = attr; |
| if let ast::AttrKind::Normal(item) = kind { |
| item.hash_stable(self, hasher); |
| style.hash_stable(self, hasher); |
| span.hash_stable(self, hasher); |
| } else { |
| unreachable!(); |
| } |
| } |
| } |
| |
| impl<'a> HashStable<StableHashingContext<'a>> for SourceFile { |
| fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) { |
| let SourceFile { |
| name: _, // We hash the smaller name_hash instead of this |
| name_hash, |
| name_was_remapped, |
| unmapped_path: _, |
| crate_of_origin, |
| // Do not hash the source as it is not encoded |
| src: _, |
| src_hash, |
| external_src: _, |
| start_pos, |
| end_pos: _, |
| ref lines, |
| ref multibyte_chars, |
| ref non_narrow_chars, |
| ref normalized_pos, |
| } = *self; |
| |
| (name_hash as u64).hash_stable(hcx, hasher); |
| name_was_remapped.hash_stable(hcx, hasher); |
| |
| DefId { krate: CrateNum::from_u32(crate_of_origin), index: CRATE_DEF_INDEX } |
| .hash_stable(hcx, hasher); |
| |
| src_hash.hash_stable(hcx, hasher); |
| |
| // We only hash the relative position within this source_file |
| lines.len().hash_stable(hcx, hasher); |
| for &line in lines.iter() { |
| stable_byte_pos(line, start_pos).hash_stable(hcx, hasher); |
| } |
| |
| // We only hash the relative position within this source_file |
| multibyte_chars.len().hash_stable(hcx, hasher); |
| for &char_pos in multibyte_chars.iter() { |
| stable_multibyte_char(char_pos, start_pos).hash_stable(hcx, hasher); |
| } |
| |
| non_narrow_chars.len().hash_stable(hcx, hasher); |
| for &char_pos in non_narrow_chars.iter() { |
| stable_non_narrow_char(char_pos, start_pos).hash_stable(hcx, hasher); |
| } |
| |
| normalized_pos.len().hash_stable(hcx, hasher); |
| for &char_pos in normalized_pos.iter() { |
| stable_normalized_pos(char_pos, start_pos).hash_stable(hcx, hasher); |
| } |
| } |
| } |
| |
| fn stable_byte_pos(pos: ::rustc_span::BytePos, source_file_start: ::rustc_span::BytePos) -> u32 { |
| pos.0 - source_file_start.0 |
| } |
| |
| fn stable_multibyte_char( |
| mbc: ::rustc_span::MultiByteChar, |
| source_file_start: ::rustc_span::BytePos, |
| ) -> (u32, u32) { |
| let ::rustc_span::MultiByteChar { pos, bytes } = mbc; |
| |
| (pos.0 - source_file_start.0, bytes as u32) |
| } |
| |
| fn stable_non_narrow_char( |
| swc: ::rustc_span::NonNarrowChar, |
| source_file_start: ::rustc_span::BytePos, |
| ) -> (u32, u32) { |
| let pos = swc.pos(); |
| let width = swc.width(); |
| |
| (pos.0 - source_file_start.0, width as u32) |
| } |
| |
| fn stable_normalized_pos( |
| np: ::rustc_span::NormalizedPos, |
| source_file_start: ::rustc_span::BytePos, |
| ) -> (u32, u32) { |
| let ::rustc_span::NormalizedPos { pos, diff } = np; |
| |
| (pos.0 - source_file_start.0, diff) |
| } |
| |
| impl<'tcx> HashStable<StableHashingContext<'tcx>> for rustc_feature::Features { |
| fn hash_stable(&self, hcx: &mut StableHashingContext<'tcx>, hasher: &mut StableHasher) { |
| // Unfortunately we cannot exhaustively list fields here, since the |
| // struct is macro generated. |
| self.declared_lang_features.hash_stable(hcx, hasher); |
| self.declared_lib_features.hash_stable(hcx, hasher); |
| |
| self.walk_feature_fields(|feature_name, value| { |
| feature_name.hash_stable(hcx, hasher); |
| value.hash_stable(hcx, hasher); |
| }); |
| } |
| } |