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::ty::{self, TyCtxt};
  10 use rustc_mir::util::{write_mir_graphviz, write_mir_pretty};
  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 super-traits.)
  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 super-traits.)
 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
 351             .source_map()
 352             .get_source_file(&src_name)
 353             .expect("get_source_file")
 354             .src
 355             .as_ref()
 356             .expect("src"),
 357     );
 358     (src, src_name)
 359 }
 360
 361 fn write_or_print(out: &str, ofile: Option<&Path>) {
 362     match ofile {
 363         None => print!("{}", out),
 364         Some(p) => {
 365             if let Err(e) = std::fs::write(p, out) {
 366                 panic!("print-print failed to write {} due to {}", p.display(), e);
 367             }
 368         }
 369     }
 370 }
 371
 372 pub fn print_after_parsing(
 373     sess: &Session,
 374     input: &Input,
 375     krate: &ast::Crate,
 376     ppm: PpMode,
 377     ofile: Option<&Path>,
 378 ) {
 379     let (src, src_name) = get_source(input, sess);
 380
 381     let out = match ppm {
 382         Source(s) => {
 383             // Silently ignores an identified node.
 384             call_with_pp_support(&s, sess, None, move |annotation| {
 385                 debug!("pretty printing source code {:?}", s);
 386                 let sess = annotation.sess();
 387                 let parse = &sess.parse_sess;
 388                 pprust::print_crate(
 389                     sess.source_map(),
 390                     krate,
 391                     src_name,
 392                     src,
 393                     annotation.pp_ann(),
 394                     false,
 395                     parse.edition,
 396                 )
 397             })
 398         }
 399         AstTree(PpAstTreeMode::Normal) => {
 400             debug!("pretty printing AST tree");
 401             format!("{:#?}", krate)
 402         }
 403         _ => unreachable!(),
 404     };
 405
 406     write_or_print(&out, ofile);
 407 }
 408
 409 pub fn print_after_hir_lowering<'tcx>(
 410     tcx: TyCtxt<'tcx>,
 411     input: &Input,
 412     krate: &ast::Crate,
 413     ppm: PpMode,
 414     ofile: Option<&Path>,
 415 ) {
 416     if ppm.needs_analysis() {
 417         abort_on_err(print_with_analysis(tcx, ppm, ofile), tcx.sess);
 418         return;
 419     }
 420
 421     let (src, src_name) = get_source(input, tcx.sess);
 422
 423     let out = match ppm {
 424         Source(s) => {
 425             // Silently ignores an identified node.
 426             call_with_pp_support(&s, tcx.sess, Some(tcx), move |annotation| {
 427                 debug!("pretty printing source code {:?}", s);
 428                 let sess = annotation.sess();
 429                 let parse = &sess.parse_sess;
 430                 pprust::print_crate(
 431                     sess.source_map(),
 432                     krate,
 433                     src_name,
 434                     src,
 435                     annotation.pp_ann(),
 436                     true,
 437                     parse.edition,
 438                 )
 439             })
 440         }
 441
 442         AstTree(PpAstTreeMode::Expanded) => {
 443             debug!("pretty-printing expanded AST");
 444             format!("{:#?}", krate)
 445         }
 446
 447         Hir(s) => call_with_pp_support_hir(&s, tcx, move |annotation, krate| {
 448             debug!("pretty printing HIR {:?}", s);
 449             let sess = annotation.sess();
 450             let sm = sess.source_map();
 451             pprust_hir::print_crate(sm, krate, src_name, src, annotation.pp_ann())
 452         }),
 453
 454         HirTree => call_with_pp_support_hir(&PpHirMode::Normal, tcx, move |_annotation, krate| {
 455             debug!("pretty printing HIR tree");
 456             format!("{:#?}", krate)
 457         }),
 458
 459         _ => unreachable!(),
 460     };
 461
 462     write_or_print(&out, ofile);
 463 }
 464
 465 // In an ideal world, this would be a public function called by the driver after
 466 // analysis is performed. However, we want to call `phase_3_run_analysis_passes`
 467 // with a different callback than the standard driver, so that isn't easy.
 468 // Instead, we call that function ourselves.
 469 fn print_with_analysis(
 470     tcx: TyCtxt<'_>,
 471     ppm: PpMode,
 472     ofile: Option<&Path>,
 473 ) -> Result<(), ErrorReported> {
 474     tcx.analysis(())?;
 475     let out = match ppm {
 476         Mir => {
 477             let mut out = Vec::new();
 478             write_mir_pretty(tcx, None, &mut out).unwrap();
 479             String::from_utf8(out).unwrap()
 480         }
 481
 482         MirCFG => {
 483             let mut out = Vec::new();
 484             write_mir_graphviz(tcx, None, &mut out).unwrap();
 485             String::from_utf8(out).unwrap()
 486         }
 487
 488         ThirTree => {
 489             let mut out = String::new();
 490             abort_on_err(rustc_typeck::check_crate(tcx), tcx.sess);
 491             debug!("pretty printing THIR tree");
 492             for did in tcx.body_owners() {
 493                 let _ = writeln!(
 494                     out,
 495                     "{:?}:\n{}\n",
 496                     did,
 497                     tcx.thir_tree(ty::WithOptConstParam::unknown(did))
 498                 );
 499             }
 500             out
 501         }
 502
 503         _ => unreachable!(),
 504     };
 505
 506     write_or_print(&out, ofile);
 507
 508     Ok(())
 509 }