compiler/rustc_driver/src/pretty.rs

   1 //! The various pretty-printing routines.
   2
   3 use rustc_ast as ast;
   4 use rustc_ast_pretty::pprust;
   5 use rustc_errors::ErrorReported;
   6 use rustc_hir as hir;
   7 use rustc_hir_pretty as pprust_hir;
   8 use rustc_middle::hir::map as hir_map;
   9 use rustc_middle::mir::{write_mir_graphviz, write_mir_pretty};
  10 use rustc_middle::ty::{self, TyCtxt};
  11 use rustc_session::config::{Input, PpAstTreeMode, PpHirMode, PpMode, PpSourceMode};
  12 use rustc_session::Session;
  13 use rustc_span::symbol::Ident;
  14 use rustc_span::FileName;
  15
  16 use std::cell::Cell;
  17 use std::fmt::Write;
  18 use std::path::Path;
  19
  20 pub use self::PpMode::*;
  21 pub use self::PpSourceMode::*;
  22 use crate::abort_on_err;
  23
  24 // This slightly awkward construction is to allow for each PpMode to
  25 // choose whether it needs to do analyses (which can consume the
  26 // Session) and then pass through the session (now attached to the
  27 // analysis results) on to the chosen pretty-printer, along with the
  28 // `&PpAnn` object.
  29 //
  30 // Note that since the `&PrinterSupport` is freshly constructed on each
  31 // call, it would not make sense to try to attach the lifetime of `self`
  32 // to the lifetime of the `&PrinterObject`.
  33
  34 /// Constructs a `PrinterSupport` object and passes it to `f`.
  35 fn call_with_pp_support<'tcx, A, F>(
  36     ppmode: &PpSourceMode,
  37     sess: &'tcx Session,
  38     tcx: Option<TyCtxt<'tcx>>,
  39     f: F,
  40 ) -> A
  41 where
  42     F: FnOnce(&dyn PrinterSupport) -> A,
  43 {
  44     match *ppmode {
  45         Normal | EveryBodyLoops | Expanded => {
  46             let annotation = NoAnn { sess, tcx };
  47             f(&annotation)
  48         }
  49
  50         Identified | ExpandedIdentified => {
  51             let annotation = IdentifiedAnnotation { sess, tcx };
  52             f(&annotation)
  53         }
  54         ExpandedHygiene => {
  55             let annotation = HygieneAnnotation { sess };
  56             f(&annotation)
  57         }
  58     }
  59 }
  60 fn call_with_pp_support_hir<A, F>(ppmode: &PpHirMode, tcx: TyCtxt<'_>, f: F) -> A
  61 where
  62     F: FnOnce(&dyn HirPrinterSupport<'_>, &hir::Crate<'_>) -> A,
  63 {
  64     match *ppmode {
  65         PpHirMode::Normal => {
  66             let annotation = NoAnn { sess: tcx.sess, tcx: Some(tcx) };
  67             f(&annotation, tcx.hir().krate())
  68         }
  69
  70         PpHirMode::Identified => {
  71             let annotation = IdentifiedAnnotation { sess: tcx.sess, tcx: Some(tcx) };
  72             f(&annotation, tcx.hir().krate())
  73         }
  74         PpHirMode::Typed => {
  75             abort_on_err(tcx.analysis(()), tcx.sess);
  76
  77             let annotation = TypedAnnotation { tcx, maybe_typeck_results: Cell::new(None) };
  78             tcx.dep_graph.with_ignore(|| f(&annotation, tcx.hir().krate()))
  79         }
  80     }
  81 }
  82
  83 trait PrinterSupport: pprust::PpAnn {
  84     /// Provides a uniform interface for re-extracting a reference to a
  85     /// `Session` from a value that now owns it.
  86     fn sess(&self) -> &Session;
  87
  88     /// Produces the pretty-print annotation object.
  89     ///
  90     /// (Rust does not yet support upcasting from a trait object to
  91     /// an object for one of its supertraits.)
  92     fn pp_ann(&self) -> &dyn pprust::PpAnn;
  93 }
  94
  95 trait HirPrinterSupport<'hir>: pprust_hir::PpAnn {
  96     /// Provides a uniform interface for re-extracting a reference to a
  97     /// `Session` from a value that now owns it.
  98     fn sess(&self) -> &Session;
  99
 100     /// Provides a uniform interface for re-extracting a reference to an
 101     /// `hir_map::Map` from a value that now owns it.
 102     fn hir_map(&self) -> Option<hir_map::Map<'hir>>;
 103
 104     /// Produces the pretty-print annotation object.
 105     ///
 106     /// (Rust does not yet support upcasting from a trait object to
 107     /// an object for one of its supertraits.)
 108     fn pp_ann(&self) -> &dyn pprust_hir::PpAnn;
 109 }
 110
 111 struct NoAnn<'hir> {
 112     sess: &'hir Session,
 113     tcx: Option<TyCtxt<'hir>>,
 114 }
 115
 116 impl<'hir> PrinterSupport for NoAnn<'hir> {
 117     fn sess(&self) -> &Session {
 118         self.sess
 119     }
 120
 121     fn pp_ann(&self) -> &dyn pprust::PpAnn {
 122         self
 123     }
 124 }
 125
 126 impl<'hir> HirPrinterSupport<'hir> for NoAnn<'hir> {
 127     fn sess(&self) -> &Session {
 128         self.sess
 129     }
 130
 131     fn hir_map(&self) -> Option<hir_map::Map<'hir>> {
 132         self.tcx.map(|tcx| tcx.hir())
 133     }
 134
 135     fn pp_ann(&self) -> &dyn pprust_hir::PpAnn {
 136         self
 137     }
 138 }
 139
 140 impl<'hir> pprust::PpAnn for NoAnn<'hir> {}
 141 impl<'hir> pprust_hir::PpAnn for NoAnn<'hir> {
 142     fn nested(&self, state: &mut pprust_hir::State<'_>, nested: pprust_hir::Nested) {
 143         if let Some(tcx) = self.tcx {
 144             pprust_hir::PpAnn::nested(&(&tcx.hir() as &dyn hir::intravisit::Map<'_>), state, nested)
 145         }
 146     }
 147 }
 148
 149 struct IdentifiedAnnotation<'hir> {
 150     sess: &'hir Session,
 151     tcx: Option<TyCtxt<'hir>>,
 152 }
 153
 154 impl<'hir> PrinterSupport for IdentifiedAnnotation<'hir> {
 155     fn sess(&self) -> &Session {
 156         self.sess
 157     }
 158
 159     fn pp_ann(&self) -> &dyn pprust::PpAnn {
 160         self
 161     }
 162 }
 163
 164 impl<'hir> pprust::PpAnn for IdentifiedAnnotation<'hir> {
 165     fn pre(&self, s: &mut pprust::State<'_>, node: pprust::AnnNode<'_>) {
 166         if let pprust::AnnNode::Expr(_) = node {
 167             s.popen();
 168         }
 169     }
 170     fn post(&self, s: &mut pprust::State<'_>, node: pprust::AnnNode<'_>) {
 171         match node {
 172             pprust::AnnNode::Crate(_) | pprust::AnnNode::Ident(_) | pprust::AnnNode::Name(_) => {}
 173
 174             pprust::AnnNode::Item(item) => {
 175                 s.s.space();
 176                 s.synth_comment(item.id.to_string())
 177             }
 178             pprust::AnnNode::SubItem(id) => {
 179                 s.s.space();
 180                 s.synth_comment(id.to_string())
 181             }
 182             pprust::AnnNode::Block(blk) => {
 183                 s.s.space();
 184                 s.synth_comment(format!("block {}", blk.id))
 185             }
 186             pprust::AnnNode::Expr(expr) => {
 187                 s.s.space();
 188                 s.synth_comment(expr.id.to_string());
 189                 s.pclose()
 190             }
 191             pprust::AnnNode::Pat(pat) => {
 192                 s.s.space();
 193                 s.synth_comment(format!("pat {}", pat.id));
 194             }
 195         }
 196     }
 197 }
 198
 199 impl<'hir> HirPrinterSupport<'hir> for IdentifiedAnnotation<'hir> {
 200     fn sess(&self) -> &Session {
 201         self.sess
 202     }
 203
 204     fn hir_map(&self) -> Option<hir_map::Map<'hir>> {
 205         self.tcx.map(|tcx| tcx.hir())
 206     }
 207
 208     fn pp_ann(&self) -> &dyn pprust_hir::PpAnn {
 209         self
 210     }
 211 }
 212
 213 impl<'hir> pprust_hir::PpAnn for IdentifiedAnnotation<'hir> {
 214     fn nested(&self, state: &mut pprust_hir::State<'_>, nested: pprust_hir::Nested) {
 215         if let Some(ref tcx) = self.tcx {
 216             pprust_hir::PpAnn::nested(&(&tcx.hir() as &dyn hir::intravisit::Map<'_>), state, nested)
 217         }
 218     }
 219     fn pre(&self, s: &mut pprust_hir::State<'_>, node: pprust_hir::AnnNode<'_>) {
 220         if let pprust_hir::AnnNode::Expr(_) = node {
 221             s.popen();
 222         }
 223     }
 224     fn post(&self, s: &mut pprust_hir::State<'_>, node: pprust_hir::AnnNode<'_>) {
 225         match node {
 226             pprust_hir::AnnNode::Name(_) => {}
 227             pprust_hir::AnnNode::Item(item) => {
 228                 s.s.space();
 229                 s.synth_comment(format!("hir_id: {}", item.hir_id()));
 230             }
 231             pprust_hir::AnnNode::SubItem(id) => {
 232                 s.s.space();
 233                 s.synth_comment(id.to_string());
 234             }
 235             pprust_hir::AnnNode::Block(blk) => {
 236                 s.s.space();
 237                 s.synth_comment(format!("block hir_id: {}", blk.hir_id));
 238             }
 239             pprust_hir::AnnNode::Expr(expr) => {
 240                 s.s.space();
 241                 s.synth_comment(format!("expr hir_id: {}", expr.hir_id));
 242                 s.pclose();
 243             }
 244             pprust_hir::AnnNode::Pat(pat) => {
 245                 s.s.space();
 246                 s.synth_comment(format!("pat hir_id: {}", pat.hir_id));
 247             }
 248             pprust_hir::AnnNode::Arm(arm) => {
 249                 s.s.space();
 250                 s.synth_comment(format!("arm hir_id: {}", arm.hir_id));
 251             }
 252         }
 253     }
 254 }
 255
 256 struct HygieneAnnotation<'a> {
 257     sess: &'a Session,
 258 }
 259
 260 impl<'a> PrinterSupport for HygieneAnnotation<'a> {
 261     fn sess(&self) -> &Session {
 262         self.sess
 263     }
 264
 265     fn pp_ann(&self) -> &dyn pprust::PpAnn {
 266         self
 267     }
 268 }
 269
 270 impl<'a> pprust::PpAnn for HygieneAnnotation<'a> {
 271     fn post(&self, s: &mut pprust::State<'_>, node: pprust::AnnNode<'_>) {
 272         match node {
 273             pprust::AnnNode::Ident(&Ident { name, span }) => {
 274                 s.s.space();
 275                 s.synth_comment(format!("{}{:?}", name.as_u32(), span.ctxt()))
 276             }
 277             pprust::AnnNode::Name(&name) => {
 278                 s.s.space();
 279                 s.synth_comment(name.as_u32().to_string())
 280             }
 281             pprust::AnnNode::Crate(_) => {
 282                 s.s.hardbreak();
 283                 let verbose = self.sess.verbose();
 284                 s.synth_comment(rustc_span::hygiene::debug_hygiene_data(verbose));
 285                 s.s.hardbreak_if_not_bol();
 286             }
 287             _ => {}
 288         }
 289     }
 290 }
 291
 292 struct TypedAnnotation<'tcx> {
 293     tcx: TyCtxt<'tcx>,
 294     maybe_typeck_results: Cell<Option<&'tcx ty::TypeckResults<'tcx>>>,
 295 }
 296
 297 impl<'tcx> HirPrinterSupport<'tcx> for TypedAnnotation<'tcx> {
 298     fn sess(&self) -> &Session {
 299         self.tcx.sess
 300     }
 301
 302     fn hir_map(&self) -> Option<hir_map::Map<'tcx>> {
 303         Some(self.tcx.hir())
 304     }
 305
 306     fn pp_ann(&self) -> &dyn pprust_hir::PpAnn {
 307         self
 308     }
 309 }
 310
 311 impl<'tcx> pprust_hir::PpAnn for TypedAnnotation<'tcx> {
 312     fn nested(&self, state: &mut pprust_hir::State<'_>, nested: pprust_hir::Nested) {
 313         let old_maybe_typeck_results = self.maybe_typeck_results.get();
 314         if let pprust_hir::Nested::Body(id) = nested {
 315             self.maybe_typeck_results.set(Some(self.tcx.typeck_body(id)));
 316         }
 317         let pp_ann = &(&self.tcx.hir() as &dyn hir::intravisit::Map<'_>);
 318         pprust_hir::PpAnn::nested(pp_ann, state, nested);
 319         self.maybe_typeck_results.set(old_maybe_typeck_results);
 320     }
 321     fn pre(&self, s: &mut pprust_hir::State<'_>, node: pprust_hir::AnnNode<'_>) {
 322         if let pprust_hir::AnnNode::Expr(_) = node {
 323             s.popen();
 324         }
 325     }
 326     fn post(&self, s: &mut pprust_hir::State<'_>, node: pprust_hir::AnnNode<'_>) {
 327         if let pprust_hir::AnnNode::Expr(expr) = node {
 328             let typeck_results = self.maybe_typeck_results.get().or_else(|| {
 329                 self.tcx
 330                     .hir()
 331                     .maybe_body_owned_by(self.tcx.hir().local_def_id_to_hir_id(expr.hir_id.owner))
 332                     .map(|body_id| self.tcx.typeck_body(body_id))
 333             });
 334
 335             if let Some(typeck_results) = typeck_results {
 336                 s.s.space();
 337                 s.s.word("as");
 338                 s.s.space();
 339                 s.s.word(typeck_results.expr_ty(expr).to_string());
 340             }
 341
 342             s.pclose();
 343         }
 344     }
 345 }
 346
 347 fn get_source(input: &Input, sess: &Session) -> (String, FileName) {
 348     let src_name = input.source_name();
 349     let src = String::clone(
 350         sess.source_map()
 351             .get_source_file(&src_name)
 352             .expect("get_source_file")
 353             .src
 354             .as_ref()
 355             .expect("src"),
 356     );
 357     (src, src_name)
 358 }
 359
 360 fn write_or_print(out: &str, ofile: Option<&Path>) {
 361     match ofile {
 362         None => print!("{}", out),
 363         Some(p) => {
 364             if let Err(e) = std::fs::write(p, out) {
 365                 panic!("print-print failed to write {} due to {}", p.display(), e);
 366             }
 367         }
 368     }
 369 }
 370
 371 pub fn print_after_parsing(
 372     sess: &Session,
 373     input: &Input,
 374     krate: &ast::Crate,
 375     ppm: PpMode,
 376     ofile: Option<&Path>,
 377 ) {
 378     let (src, src_name) = get_source(input, sess);
 379
 380     let out = match ppm {
 381         Source(s) => {
 382             // Silently ignores an identified node.
 383             call_with_pp_support(&s, sess, None, move |annotation| {
 384                 debug!("pretty printing source code {:?}", s);
 385                 let sess = annotation.sess();
 386                 let parse = &sess.parse_sess;
 387                 pprust::print_crate(
 388                     sess.source_map(),
 389                     krate,
 390                     src_name,
 391                     src,
 392                     annotation.pp_ann(),
 393                     false,
 394                     parse.edition,
 395                 )
 396             })
 397         }
 398         AstTree(PpAstTreeMode::Normal) => {
 399             debug!("pretty printing AST tree");
 400             format!("{:#?}", krate)
 401         }
 402         _ => unreachable!(),
 403     };
 404
 405     write_or_print(&out, ofile);
 406 }
 407
 408 pub fn print_after_hir_lowering<'tcx>(
 409     tcx: TyCtxt<'tcx>,
 410     input: &Input,
 411     krate: &ast::Crate,
 412     ppm: PpMode,
 413     ofile: Option<&Path>,
 414 ) {
 415     if ppm.needs_analysis() {
 416         abort_on_err(print_with_analysis(tcx, ppm, ofile), tcx.sess);
 417         return;
 418     }
 419
 420     let (src, src_name) = get_source(input, tcx.sess);
 421
 422     let out = match ppm {
 423         Source(s) => {
 424             // Silently ignores an identified node.
 425             call_with_pp_support(&s, tcx.sess, Some(tcx), move |annotation| {
 426                 debug!("pretty printing source code {:?}", s);
 427                 let sess = annotation.sess();
 428                 let parse = &sess.parse_sess;
 429                 pprust::print_crate(
 430                     sess.source_map(),
 431                     krate,
 432                     src_name,
 433                     src,
 434                     annotation.pp_ann(),
 435                     true,
 436                     parse.edition,
 437                 )
 438             })
 439         }
 440
 441         AstTree(PpAstTreeMode::Expanded) => {
 442             debug!("pretty-printing expanded AST");
 443             format!("{:#?}", krate)
 444         }
 445
 446         Hir(s) => call_with_pp_support_hir(&s, tcx, move |annotation, krate| {
 447             debug!("pretty printing HIR {:?}", s);
 448             let sess = annotation.sess();
 449             let sm = sess.source_map();
 450             pprust_hir::print_crate(sm, krate, src_name, src, annotation.pp_ann())
 451         }),
 452
 453         HirTree => call_with_pp_support_hir(&PpHirMode::Normal, tcx, move |_annotation, krate| {
 454             debug!("pretty printing HIR tree");
 455             format!("{:#?}", krate)
 456         }),
 457
 458         _ => unreachable!(),
 459     };
 460
 461     write_or_print(&out, ofile);
 462 }
 463
 464 // In an ideal world, this would be a public function called by the driver after
 465 // analysis is performed. However, we want to call `phase_3_run_analysis_passes`
 466 // with a different callback than the standard driver, so that isn't easy.
 467 // Instead, we call that function ourselves.
 468 fn print_with_analysis(
 469     tcx: TyCtxt<'_>,
 470     ppm: PpMode,
 471     ofile: Option<&Path>,
 472 ) -> Result<(), ErrorReported> {
 473     tcx.analysis(())?;
 474     let out = match ppm {
 475         Mir => {
 476             let mut out = Vec::new();
 477             write_mir_pretty(tcx, None, &mut out).unwrap();
 478             String::from_utf8(out).unwrap()
 479         }
 480
 481         MirCFG => {
 482             let mut out = Vec::new();
 483             write_mir_graphviz(tcx, None, &mut out).unwrap();
 484             String::from_utf8(out).unwrap()
 485         }
 486
 487         ThirTree => {
 488             let mut out = String::new();
 489             abort_on_err(rustc_typeck::check_crate(tcx), tcx.sess);
 490             debug!("pretty printing THIR tree");
 491             for did in tcx.hir().body_owners() {
 492                 let _ = writeln!(
 493                     out,
 494                     "{:?}:\n{}\n",
 495                     did,
 496                     tcx.thir_tree(ty::WithOptConstParam::unknown(did))
 497                 );
 498             }
 499             out
 500         }
 501
 502         _ => unreachable!(),
 503     };
 504
 505     write_or_print(&out, ofile);
 506
 507     Ok(())
 508 }