compiler/rustc_session/src/utils.rs

   1 use crate::parse::ParseSess;
   2 use crate::session::Session;
   3 use rustc_ast::token::{self, DelimToken, Nonterminal, Token};
   4 use rustc_ast::tokenstream::CanSynthesizeMissingTokens;
   5 use rustc_ast::tokenstream::{DelimSpan, TokenStream, TokenTree};
   6 use rustc_data_structures::profiling::VerboseTimingGuard;
   7 use std::path::{Path, PathBuf};
   8
   9 pub type NtToTokenstream = fn(&Nonterminal, &ParseSess, CanSynthesizeMissingTokens) -> TokenStream;
  10
  11 impl Session {
  12     pub fn timer<'a>(&'a self, what: &'static str) -> VerboseTimingGuard<'a> {
  13         self.prof.verbose_generic_activity(what)
  14     }
  15     pub fn time<R>(&self, what: &'static str, f: impl FnOnce() -> R) -> R {
  16         self.prof.verbose_generic_activity(what).run(f)
  17     }
  18 }
  19
  20 #[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Encodable, Decodable)]
  21 pub enum NativeLibKind {
  22     /// Static library (e.g. `libfoo.a` on Linux or `foo.lib` on Windows/MSVC) included
  23     /// when linking a final binary, but not when archiving an rlib.
  24     StaticNoBundle,
  25     /// Static library (e.g. `libfoo.a` on Linux or `foo.lib` on Windows/MSVC) included
  26     /// when linking a final binary, but also included when archiving an rlib.
  27     StaticBundle,
  28     /// Dynamic library (e.g. `libfoo.so` on Linux)
  29     /// or an import library corresponding to a dynamic library (e.g. `foo.lib` on Windows/MSVC).
  30     Dylib,
  31     /// Dynamic library (e.g. `foo.dll` on Windows) without a corresponding import library.
  32     RawDylib,
  33     /// A macOS-specific kind of dynamic libraries.
  34     Framework,
  35     /// The library kind wasn't specified, `Dylib` is currently used as a default.
  36     Unspecified,
  37 }
  38
  39 rustc_data_structures::impl_stable_hash_via_hash!(NativeLibKind);
  40
  41 /// A path that has been canonicalized along with its original, non-canonicalized form
  42 #[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
  43 pub struct CanonicalizedPath {
  44     // Optional since canonicalization can sometimes fail
  45     canonicalized: Option<PathBuf>,
  46     original: PathBuf,
  47 }
  48
  49 impl CanonicalizedPath {
  50     pub fn new(path: &Path) -> Self {
  51         Self { original: path.to_owned(), canonicalized: std::fs::canonicalize(path).ok() }
  52     }
  53
  54     pub fn canonicalized(&self) -> &PathBuf {
  55         self.canonicalized.as_ref().unwrap_or(self.original())
  56     }
  57
  58     pub fn original(&self) -> &PathBuf {
  59         &self.original
  60     }
  61 }
  62
  63 // FIXME: Find a better spot for this - it needs to be accessible from `rustc_ast_lowering`,
  64 // and needs to access `ParseSess
  65 pub struct FlattenNonterminals<'a> {
  66     pub parse_sess: &'a ParseSess,
  67     pub synthesize_tokens: CanSynthesizeMissingTokens,
  68     pub nt_to_tokenstream: NtToTokenstream,
  69 }
  70
  71 impl<'a> FlattenNonterminals<'a> {
  72     pub fn process_token_stream(&mut self, tokens: TokenStream) -> TokenStream {
  73         fn can_skip(stream: &TokenStream) -> bool {
  74             stream.trees().all(|tree| match tree {
  75                 TokenTree::Token(token) => !matches!(token.kind, token::Interpolated(_)),
  76                 TokenTree::Delimited(_, _, inner) => can_skip(&inner),
  77             })
  78         }
  79
  80         if can_skip(&tokens) {
  81             return tokens;
  82         }
  83
  84         tokens.into_trees().flat_map(|tree| self.process_token_tree(tree).into_trees()).collect()
  85     }
  86
  87     pub fn process_token_tree(&mut self, tree: TokenTree) -> TokenStream {
  88         match tree {
  89             TokenTree::Token(token) => self.process_token(token),
  90             TokenTree::Delimited(span, delim, tts) => {
  91                 TokenTree::Delimited(span, delim, self.process_token_stream(tts)).into()
  92             }
  93         }
  94     }
  95
  96     pub fn process_token(&mut self, token: Token) -> TokenStream {
  97         match token.kind {
  98             token::Interpolated(nt) => {
  99                 let tts = (self.nt_to_tokenstream)(&nt, self.parse_sess, self.synthesize_tokens);
 100                 TokenTree::Delimited(
 101                     DelimSpan::from_single(token.span),
 102                     DelimToken::NoDelim,
 103                     self.process_token_stream(tts),
 104                 )
 105                 .into()
 106             }
 107             _ => TokenTree::Token(token).into(),
 108         }
 109     }
 110 }