src/librustc_driver/pretty.rs

   1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 //! The various pretty print routines.
  12
  13 pub use self::UserIdentifiedItem::*;
  14 pub use self::PpSourceMode::*;
  15 pub use self::PpMode::*;
  16 use self::NodesMatchingUII::*;
  17
  18 use {abort_on_err, driver};
  19
  20 use rustc::ty::{self, TyCtxt, Resolutions, AllArenas};
  21 use rustc::cfg;
  22 use rustc::cfg::graphviz::LabelledCFG;
  23 use rustc::session::Session;
  24 use rustc::session::config::{Input, OutputFilenames};
  25 use rustc_borrowck as borrowck;
  26 use rustc_borrowck::graphviz as borrowck_dot;
  27 use rustc_data_structures::thin_vec::ThinVec;
  28 use rustc_metadata::cstore::CStore;
  29
  30 use rustc_mir::util::{write_mir_pretty, write_mir_graphviz};
  31
  32 use syntax::ast::{self, BlockCheckMode};
  33 use syntax::fold::{self, Folder};
  34 use syntax::print::{pprust};
  35 use syntax::print::pprust::PrintState;
  36 use syntax::ptr::P;
  37 use syntax_pos::{self, FileName};
  38
  39 use graphviz as dot;
  40 use smallvec::SmallVec;
  41
  42 use std::cell::Cell;
  43 use std::fs::File;
  44 use std::io::{self, Write};
  45 use std::option;
  46 use std::path::Path;
  47 use std::str::FromStr;
  48 use std::mem;
  49
  50 use rustc::hir::map as hir_map;
  51 use rustc::hir::map::blocks;
  52 use rustc::hir;
  53 use rustc::hir::print as pprust_hir;
  54
  55 #[derive(Copy, Clone, PartialEq, Debug)]
  56 pub enum PpSourceMode {
  57     PpmNormal,
  58     PpmEveryBodyLoops,
  59     PpmExpanded,
  60     PpmIdentified,
  61     PpmExpandedIdentified,
  62     PpmExpandedHygiene,
  63     PpmTyped,
  64 }
  65
  66 #[derive(Copy, Clone, PartialEq, Debug)]
  67 pub enum PpFlowGraphMode {
  68     Default,
  69     /// Drops the labels from the edges in the flowgraph output. This
  70     /// is mostly for use in the -Z unpretty flowgraph run-make tests,
  71     /// since the labels are largely uninteresting in those cases and
  72     /// have become a pain to maintain.
  73     UnlabelledEdges,
  74 }
  75 #[derive(Copy, Clone, PartialEq, Debug)]
  76 pub enum PpMode {
  77     PpmSource(PpSourceMode),
  78     PpmHir(PpSourceMode),
  79     PpmHirTree(PpSourceMode),
  80     PpmFlowGraph(PpFlowGraphMode),
  81     PpmMir,
  82     PpmMirCFG,
  83 }
  84
  85 impl PpMode {
  86     pub fn needs_ast_map(&self, opt_uii: &Option<UserIdentifiedItem>) -> bool {
  87         match *self {
  88             PpmSource(PpmNormal) |
  89             PpmSource(PpmEveryBodyLoops) |
  90             PpmSource(PpmIdentified) => opt_uii.is_some(),
  91
  92             PpmSource(PpmExpanded) |
  93             PpmSource(PpmExpandedIdentified) |
  94             PpmSource(PpmExpandedHygiene) |
  95             PpmHir(_) |
  96             PpmHirTree(_) |
  97             PpmMir |
  98             PpmMirCFG |
  99             PpmFlowGraph(_) => true,
 100             PpmSource(PpmTyped) => panic!("invalid state"),
 101         }
 102     }
 103
 104     pub fn needs_analysis(&self) -> bool {
 105         match *self {
 106             PpmMir | PpmMirCFG | PpmFlowGraph(_) => true,
 107             _ => false,
 108         }
 109     }
 110 }
 111
 112 pub fn parse_pretty(sess: &Session,
 113                     name: &str,
 114                     extended: bool)
 115                     -> (PpMode, Option<UserIdentifiedItem>) {
 116     let mut split = name.splitn(2, '=');
 117     let first = split.next().unwrap();
 118     let opt_second = split.next();
 119     let first = match (first, extended) {
 120         ("normal", _) => PpmSource(PpmNormal),
 121         ("identified", _) => PpmSource(PpmIdentified),
 122         ("everybody_loops", true) => PpmSource(PpmEveryBodyLoops),
 123         ("expanded", _) => PpmSource(PpmExpanded),
 124         ("expanded,identified", _) => PpmSource(PpmExpandedIdentified),
 125         ("expanded,hygiene", _) => PpmSource(PpmExpandedHygiene),
 126         ("hir", true) => PpmHir(PpmNormal),
 127         ("hir,identified", true) => PpmHir(PpmIdentified),
 128         ("hir,typed", true) => PpmHir(PpmTyped),
 129         ("hir-tree", true) => PpmHirTree(PpmNormal),
 130         ("mir", true) => PpmMir,
 131         ("mir-cfg", true) => PpmMirCFG,
 132         ("flowgraph", true) => PpmFlowGraph(PpFlowGraphMode::Default),
 133         ("flowgraph,unlabelled", true) => PpmFlowGraph(PpFlowGraphMode::UnlabelledEdges),
 134         _ => {
 135             if extended {
 136                 sess.fatal(&format!("argument to `unpretty` must be one of `normal`, \
 137                                      `expanded`, `flowgraph[,unlabelled]=<nodeid>`, \
 138                                      `identified`, `expanded,identified`, `everybody_loops`, \
 139                                      `hir`, `hir,identified`, `hir,typed`, or `mir`; got {}",
 140                                     name));
 141             } else {
 142                 sess.fatal(&format!("argument to `pretty` must be one of `normal`, `expanded`, \
 143                                      `identified`, or `expanded,identified`; got {}",
 144                                     name));
 145             }
 146         }
 147     };
 148     let opt_second = opt_second.and_then(|s| s.parse::<UserIdentifiedItem>().ok());
 149     (first, opt_second)
 150 }
 151
 152
 153
 154 // This slightly awkward construction is to allow for each PpMode to
 155 // choose whether it needs to do analyses (which can consume the
 156 // Session) and then pass through the session (now attached to the
 157 // analysis results) on to the chosen pretty-printer, along with the
 158 // `&PpAnn` object.
 159 //
 160 // Note that since the `&PrinterSupport` is freshly constructed on each
 161 // call, it would not make sense to try to attach the lifetime of `self`
 162 // to the lifetime of the `&PrinterObject`.
 163 //
 164 // (The `use_once_payload` is working around the current lack of once
 165 // functions in the compiler.)
 166
 167 impl PpSourceMode {
 168     /// Constructs a `PrinterSupport` object and passes it to `f`.
 169     fn call_with_pp_support<'tcx, A, F>(&self,
 170                                         sess: &'tcx Session,
 171                                         hir_map: Option<&hir_map::Map<'tcx>>,
 172                                         f: F)
 173                                         -> A
 174         where F: FnOnce(&dyn PrinterSupport) -> A
 175     {
 176         match *self {
 177             PpmNormal | PpmEveryBodyLoops | PpmExpanded => {
 178                 let annotation = NoAnn {
 179                     sess,
 180                     hir_map: hir_map.map(|m| m.clone()),
 181                 };
 182                 f(&annotation)
 183             }
 184
 185             PpmIdentified | PpmExpandedIdentified => {
 186                 let annotation = IdentifiedAnnotation {
 187                     sess,
 188                     hir_map: hir_map.map(|m| m.clone()),
 189                 };
 190                 f(&annotation)
 191             }
 192             PpmExpandedHygiene => {
 193                 let annotation = HygieneAnnotation {
 194                     sess,
 195                 };
 196                 f(&annotation)
 197             }
 198             _ => panic!("Should use call_with_pp_support_hir"),
 199         }
 200     }
 201     fn call_with_pp_support_hir<'tcx, A, F>(
 202         &self,
 203         sess: &'tcx Session,
 204         cstore: &'tcx CStore,
 205         hir_map: &hir_map::Map<'tcx>,
 206         analysis: &ty::CrateAnalysis,
 207         resolutions: &Resolutions,
 208         arenas: &'tcx AllArenas<'tcx>,
 209         output_filenames: &OutputFilenames,
 210         id: &str,
 211         f: F
 212     ) -> A
 213         where F: FnOnce(&dyn HirPrinterSupport, &hir::Crate) -> A
 214     {
 215         match *self {
 216             PpmNormal => {
 217                 let annotation = NoAnn {
 218                     sess,
 219                     hir_map: Some(hir_map.clone()),
 220                 };
 221                 f(&annotation, hir_map.forest.krate())
 222             }
 223
 224             PpmIdentified => {
 225                 let annotation = IdentifiedAnnotation {
 226                     sess,
 227                     hir_map: Some(hir_map.clone()),
 228                 };
 229                 f(&annotation, hir_map.forest.krate())
 230             }
 231             PpmTyped => {
 232                 let control = &driver::CompileController::basic();
 233                 let codegen_backend = ::get_codegen_backend(sess);
 234                 abort_on_err(driver::phase_3_run_analysis_passes(&*codegen_backend,
 235                                                                  control,
 236                                                                  sess,
 237                                                                  cstore,
 238                                                                  hir_map.clone(),
 239                                                                  analysis.clone(),
 240                                                                  resolutions.clone(),
 241                                                                  arenas,
 242                                                                  id,
 243                                                                  output_filenames,
 244                                                                  |tcx, _, _, _| {
 245                     let empty_tables = ty::TypeckTables::empty(None);
 246                     let annotation = TypedAnnotation {
 247                         tcx,
 248                         tables: Cell::new(&empty_tables)
 249                     };
 250                     tcx.dep_graph.with_ignore(|| {
 251                         f(&annotation, hir_map.forest.krate())
 252                     })
 253                 }),
 254                              sess)
 255             }
 256             _ => panic!("Should use call_with_pp_support"),
 257         }
 258     }
 259 }
 260
 261 trait PrinterSupport: pprust::PpAnn {
 262     /// Provides a uniform interface for re-extracting a reference to a
 263     /// `Session` from a value that now owns it.
 264     fn sess<'a>(&'a self) -> &'a Session;
 265
 266     /// Produces the pretty-print annotation object.
 267     ///
 268     /// (Rust does not yet support upcasting from a trait object to
 269     /// an object for one of its super-traits.)
 270     fn pp_ann<'a>(&'a self) -> &'a dyn pprust::PpAnn;
 271 }
 272
 273 trait HirPrinterSupport<'hir>: pprust_hir::PpAnn {
 274     /// Provides a uniform interface for re-extracting a reference to a
 275     /// `Session` from a value that now owns it.
 276     fn sess<'a>(&'a self) -> &'a Session;
 277
 278     /// Provides a uniform interface for re-extracting a reference to an
 279     /// `hir_map::Map` from a value that now owns it.
 280     fn hir_map<'a>(&'a self) -> Option<&'a hir_map::Map<'hir>>;
 281
 282     /// Produces the pretty-print annotation object.
 283     ///
 284     /// (Rust does not yet support upcasting from a trait object to
 285     /// an object for one of its super-traits.)
 286     fn pp_ann<'a>(&'a self) -> &'a dyn pprust_hir::PpAnn;
 287
 288     /// Computes an user-readable representation of a path, if possible.
 289     fn node_path(&self, id: ast::NodeId) -> Option<String> {
 290         self.hir_map().and_then(|map| map.def_path_from_id(id)).map(|path| {
 291             path.data
 292                 .into_iter()
 293                 .map(|elem| elem.data.to_string())
 294                 .collect::<Vec<_>>()
 295                 .join("::")
 296         })
 297     }
 298 }
 299
 300 struct NoAnn<'hir> {
 301     sess: &'hir Session,
 302     hir_map: Option<hir_map::Map<'hir>>,
 303 }
 304
 305 impl<'hir> PrinterSupport for NoAnn<'hir> {
 306     fn sess<'a>(&'a self) -> &'a Session {
 307         self.sess
 308     }
 309
 310     fn pp_ann<'a>(&'a self) -> &'a dyn pprust::PpAnn {
 311         self
 312     }
 313 }
 314
 315 impl<'hir> HirPrinterSupport<'hir> for NoAnn<'hir> {
 316     fn sess<'a>(&'a self) -> &'a Session {
 317         self.sess
 318     }
 319
 320     fn hir_map<'a>(&'a self) -> Option<&'a hir_map::Map<'hir>> {
 321         self.hir_map.as_ref()
 322     }
 323
 324     fn pp_ann<'a>(&'a self) -> &'a dyn pprust_hir::PpAnn {
 325         self
 326     }
 327 }
 328
 329 impl<'hir> pprust::PpAnn for NoAnn<'hir> {}
 330 impl<'hir> pprust_hir::PpAnn for NoAnn<'hir> {
 331     fn nested(&self, state: &mut pprust_hir::State, nested: pprust_hir::Nested)
 332               -> io::Result<()> {
 333         if let Some(ref map) = self.hir_map {
 334             pprust_hir::PpAnn::nested(map, state, nested)
 335         } else {
 336             Ok(())
 337         }
 338     }
 339 }
 340
 341 struct IdentifiedAnnotation<'hir> {
 342     sess: &'hir Session,
 343     hir_map: Option<hir_map::Map<'hir>>,
 344 }
 345
 346 impl<'hir> PrinterSupport for IdentifiedAnnotation<'hir> {
 347     fn sess<'a>(&'a self) -> &'a Session {
 348         self.sess
 349     }
 350
 351     fn pp_ann<'a>(&'a self) -> &'a dyn pprust::PpAnn {
 352         self
 353     }
 354 }
 355
 356 impl<'hir> pprust::PpAnn for IdentifiedAnnotation<'hir> {
 357     fn pre(&self, s: &mut pprust::State, node: pprust::AnnNode) -> io::Result<()> {
 358         match node {
 359             pprust::AnnNode::Expr(_) => s.popen(),
 360             _ => Ok(()),
 361         }
 362     }
 363     fn post(&self, s: &mut pprust::State, node: pprust::AnnNode) -> io::Result<()> {
 364         match node {
 365             pprust::AnnNode::Ident(_) |
 366             pprust::AnnNode::Name(_) => Ok(()),
 367
 368             pprust::AnnNode::Item(item) => {
 369                 s.s.space()?;
 370                 s.synth_comment(item.id.to_string())
 371             }
 372             pprust::AnnNode::SubItem(id) => {
 373                 s.s.space()?;
 374                 s.synth_comment(id.to_string())
 375             }
 376             pprust::AnnNode::Block(blk) => {
 377                 s.s.space()?;
 378                 s.synth_comment(format!("block {}", blk.id))
 379             }
 380             pprust::AnnNode::Expr(expr) => {
 381                 s.s.space()?;
 382                 s.synth_comment(expr.id.to_string())?;
 383                 s.pclose()
 384             }
 385             pprust::AnnNode::Pat(pat) => {
 386                 s.s.space()?;
 387                 s.synth_comment(format!("pat {}", pat.id))
 388             }
 389         }
 390     }
 391 }
 392
 393 impl<'hir> HirPrinterSupport<'hir> for IdentifiedAnnotation<'hir> {
 394     fn sess<'a>(&'a self) -> &'a Session {
 395         self.sess
 396     }
 397
 398     fn hir_map<'a>(&'a self) -> Option<&'a hir_map::Map<'hir>> {
 399         self.hir_map.as_ref()
 400     }
 401
 402     fn pp_ann<'a>(&'a self) -> &'a dyn pprust_hir::PpAnn {
 403         self
 404     }
 405 }
 406
 407 impl<'hir> pprust_hir::PpAnn for IdentifiedAnnotation<'hir> {
 408     fn nested(&self, state: &mut pprust_hir::State, nested: pprust_hir::Nested)
 409               -> io::Result<()> {
 410         if let Some(ref map) = self.hir_map {
 411             pprust_hir::PpAnn::nested(map, state, nested)
 412         } else {
 413             Ok(())
 414         }
 415     }
 416     fn pre(&self, s: &mut pprust_hir::State, node: pprust_hir::AnnNode) -> io::Result<()> {
 417         match node {
 418             pprust_hir::AnnNode::Expr(_) => s.popen(),
 419             _ => Ok(()),
 420         }
 421     }
 422     fn post(&self, s: &mut pprust_hir::State, node: pprust_hir::AnnNode) -> io::Result<()> {
 423         match node {
 424             pprust_hir::AnnNode::Name(_) => Ok(()),
 425             pprust_hir::AnnNode::Item(item) => {
 426                 s.s.space()?;
 427                 s.synth_comment(format!("node_id: {} hir local_id: {}",
 428                                         item.id, item.hir_id.local_id.0))
 429             }
 430             pprust_hir::AnnNode::SubItem(id) => {
 431                 s.s.space()?;
 432                 s.synth_comment(id.to_string())
 433             }
 434             pprust_hir::AnnNode::Block(blk) => {
 435                 s.s.space()?;
 436                 s.synth_comment(format!("block node_id: {} hir local_id: {}",
 437                                         blk.id, blk.hir_id.local_id.0))
 438             }
 439             pprust_hir::AnnNode::Expr(expr) => {
 440                 s.s.space()?;
 441                 s.synth_comment(format!("node_id: {} hir local_id: {}",
 442                                         expr.id, expr.hir_id.local_id.0))?;
 443                 s.pclose()
 444             }
 445             pprust_hir::AnnNode::Pat(pat) => {
 446                 s.s.space()?;
 447                 s.synth_comment(format!("pat node_id: {} hir local_id: {}",
 448                                         pat.id, pat.hir_id.local_id.0))
 449             }
 450         }
 451     }
 452 }
 453
 454 struct HygieneAnnotation<'a> {
 455     sess: &'a Session
 456 }
 457
 458 impl<'a> PrinterSupport for HygieneAnnotation<'a> {
 459     fn sess(&self) -> &Session {
 460         self.sess
 461     }
 462
 463     fn pp_ann(&self) -> &dyn pprust::PpAnn {
 464         self
 465     }
 466 }
 467
 468 impl<'a> pprust::PpAnn for HygieneAnnotation<'a> {
 469     fn post(&self, s: &mut pprust::State, node: pprust::AnnNode) -> io::Result<()> {
 470         match node {
 471             pprust::AnnNode::Ident(&ast::Ident { name, span }) => {
 472                 s.s.space()?;
 473                 // FIXME #16420: this doesn't display the connections
 474                 // between syntax contexts
 475                 s.synth_comment(format!("{}{:?}", name.as_u32(), span.ctxt()))
 476             }
 477             pprust::AnnNode::Name(&name) => {
 478                 s.s.space()?;
 479                 s.synth_comment(name.as_u32().to_string())
 480             }
 481             _ => Ok(()),
 482         }
 483     }
 484 }
 485
 486
 487 struct TypedAnnotation<'a, 'tcx: 'a> {
 488     tcx: TyCtxt<'a, 'tcx, 'tcx>,
 489     tables: Cell<&'a ty::TypeckTables<'tcx>>,
 490 }
 491
 492 impl<'b, 'tcx> HirPrinterSupport<'tcx> for TypedAnnotation<'b, 'tcx> {
 493     fn sess<'a>(&'a self) -> &'a Session {
 494         &self.tcx.sess
 495     }
 496
 497     fn hir_map<'a>(&'a self) -> Option<&'a hir_map::Map<'tcx>> {
 498         Some(&self.tcx.hir)
 499     }
 500
 501     fn pp_ann<'a>(&'a self) -> &'a dyn pprust_hir::PpAnn {
 502         self
 503     }
 504
 505     fn node_path(&self, id: ast::NodeId) -> Option<String> {
 506         Some(self.tcx.node_path_str(id))
 507     }
 508 }
 509
 510 impl<'a, 'tcx> pprust_hir::PpAnn for TypedAnnotation<'a, 'tcx> {
 511     fn nested(&self, state: &mut pprust_hir::State, nested: pprust_hir::Nested)
 512               -> io::Result<()> {
 513         let old_tables = self.tables.get();
 514         if let pprust_hir::Nested::Body(id) = nested {
 515             self.tables.set(self.tcx.body_tables(id));
 516         }
 517         pprust_hir::PpAnn::nested(&self.tcx.hir, state, nested)?;
 518         self.tables.set(old_tables);
 519         Ok(())
 520     }
 521     fn pre(&self, s: &mut pprust_hir::State, node: pprust_hir::AnnNode) -> io::Result<()> {
 522         match node {
 523             pprust_hir::AnnNode::Expr(_) => s.popen(),
 524             _ => Ok(()),
 525         }
 526     }
 527     fn post(&self, s: &mut pprust_hir::State, node: pprust_hir::AnnNode) -> io::Result<()> {
 528         match node {
 529             pprust_hir::AnnNode::Expr(expr) => {
 530                 s.s.space()?;
 531                 s.s.word("as")?;
 532                 s.s.space()?;
 533                 s.s.word(&self.tables.get().expr_ty(expr).to_string())?;
 534                 s.pclose()
 535             }
 536             _ => Ok(()),
 537         }
 538     }
 539 }
 540
 541 fn gather_flowgraph_variants(sess: &Session) -> Vec<borrowck_dot::Variant> {
 542     let print_loans = sess.opts.debugging_opts.flowgraph_print_loans;
 543     let print_moves = sess.opts.debugging_opts.flowgraph_print_moves;
 544     let print_assigns = sess.opts.debugging_opts.flowgraph_print_assigns;
 545     let print_all = sess.opts.debugging_opts.flowgraph_print_all;
 546     let mut variants = Vec::new();
 547     if print_all || print_loans {
 548         variants.push(borrowck_dot::Loans);
 549     }
 550     if print_all || print_moves {
 551         variants.push(borrowck_dot::Moves);
 552     }
 553     if print_all || print_assigns {
 554         variants.push(borrowck_dot::Assigns);
 555     }
 556     variants
 557 }
 558
 559 #[derive(Clone, Debug)]
 560 pub enum UserIdentifiedItem {
 561     ItemViaNode(ast::NodeId),
 562     ItemViaPath(Vec<String>),
 563 }
 564
 565 impl FromStr for UserIdentifiedItem {
 566     type Err = ();
 567     fn from_str(s: &str) -> Result<UserIdentifiedItem, ()> {
 568         Ok(s.parse()
 569             .map(ast::NodeId::new)
 570             .map(ItemViaNode)
 571             .unwrap_or_else(|_| ItemViaPath(s.split("::").map(|s| s.to_string()).collect())))
 572     }
 573 }
 574
 575 enum NodesMatchingUII<'a, 'hir: 'a> {
 576     NodesMatchingDirect(option::IntoIter<ast::NodeId>),
 577     NodesMatchingSuffix(hir_map::NodesMatchingSuffix<'a, 'hir>),
 578 }
 579
 580 impl<'a, 'hir> Iterator for NodesMatchingUII<'a, 'hir> {
 581     type Item = ast::NodeId;
 582
 583     fn next(&mut self) -> Option<ast::NodeId> {
 584         match self {
 585             &mut NodesMatchingDirect(ref mut iter) => iter.next(),
 586             &mut NodesMatchingSuffix(ref mut iter) => iter.next(),
 587         }
 588     }
 589
 590     fn size_hint(&self) -> (usize, Option<usize>) {
 591         match self {
 592             &NodesMatchingDirect(ref iter) => iter.size_hint(),
 593             &NodesMatchingSuffix(ref iter) => iter.size_hint(),
 594         }
 595     }
 596 }
 597
 598 impl UserIdentifiedItem {
 599     fn reconstructed_input(&self) -> String {
 600         match *self {
 601             ItemViaNode(node_id) => node_id.to_string(),
 602             ItemViaPath(ref parts) => parts.join("::"),
 603         }
 604     }
 605
 606     fn all_matching_node_ids<'a, 'hir>(&'a self,
 607                                        map: &'a hir_map::Map<'hir>)
 608                                        -> NodesMatchingUII<'a, 'hir> {
 609         match *self {
 610             ItemViaNode(node_id) => NodesMatchingDirect(Some(node_id).into_iter()),
 611             ItemViaPath(ref parts) => NodesMatchingSuffix(map.nodes_matching_suffix(&parts)),
 612         }
 613     }
 614
 615     fn to_one_node_id(self, user_option: &str, sess: &Session, map: &hir_map::Map) -> ast::NodeId {
 616         let fail_because = |is_wrong_because| -> ast::NodeId {
 617             let message = format!("{} needs NodeId (int) or unique path suffix (b::c::d); got \
 618                                    {}, which {}",
 619                                   user_option,
 620                                   self.reconstructed_input(),
 621                                   is_wrong_because);
 622             sess.fatal(&message)
 623         };
 624
 625         let mut saw_node = ast::DUMMY_NODE_ID;
 626         let mut seen = 0;
 627         for node in self.all_matching_node_ids(map) {
 628             saw_node = node;
 629             seen += 1;
 630             if seen > 1 {
 631                 fail_because("does not resolve uniquely");
 632             }
 633         }
 634         if seen == 0 {
 635             fail_because("does not resolve to any item");
 636         }
 637
 638         assert!(seen == 1);
 639         return saw_node;
 640     }
 641 }
 642
 643 // Note: Also used by librustdoc, see PR #43348. Consider moving this struct elsewhere.
 644 //
 645 // FIXME: Currently the `everybody_loops` transformation is not applied to:
 646 //  * `const fn`, due to issue #43636 that `loop` is not supported for const evaluation. We are
 647 //    waiting for miri to fix that.
 648 //  * `impl Trait`, due to issue #43869 that functions returning impl Trait cannot be diverging.
 649 //    Solving this may require `!` to implement every trait, which relies on the an even more
 650 //    ambitious form of the closed RFC #1637. See also [#34511].
 651 //
 652 // [#34511]: https://github.com/rust-lang/rust/issues/34511#issuecomment-322340401
 653 pub struct ReplaceBodyWithLoop<'a> {
 654     within_static_or_const: bool,
 655     nested_blocks: Option<Vec<ast::Block>>,
 656     sess: &'a Session,
 657 }
 658
 659 impl<'a> ReplaceBodyWithLoop<'a> {
 660     pub fn new(sess: &'a Session) -> ReplaceBodyWithLoop<'a> {
 661         ReplaceBodyWithLoop {
 662             within_static_or_const: false,
 663             nested_blocks: None,
 664             sess
 665         }
 666     }
 667
 668     fn run<R, F: FnOnce(&mut Self) -> R>(&mut self, is_const: bool, action: F) -> R {
 669         let old_const = mem::replace(&mut self.within_static_or_const, is_const);
 670         let old_blocks = self.nested_blocks.take();
 671         let ret = action(self);
 672         self.within_static_or_const = old_const;
 673         self.nested_blocks = old_blocks;
 674         ret
 675     }
 676
 677     fn should_ignore_fn(ret_ty: &ast::FnDecl) -> bool {
 678         if let ast::FunctionRetTy::Ty(ref ty) = ret_ty.output {
 679             fn involves_impl_trait(ty: &ast::Ty) -> bool {
 680                 match ty.node {
 681                     ast::TyKind::ImplTrait(..) => true,
 682                     ast::TyKind::Slice(ref subty) |
 683                     ast::TyKind::Array(ref subty, _) |
 684                     ast::TyKind::Ptr(ast::MutTy { ty: ref subty, .. }) |
 685                     ast::TyKind::Rptr(_, ast::MutTy { ty: ref subty, .. }) |
 686                     ast::TyKind::Paren(ref subty) => involves_impl_trait(subty),
 687                     ast::TyKind::Tup(ref tys) => any_involves_impl_trait(tys.iter()),
 688                     ast::TyKind::Path(_, ref path) => path.segments.iter().any(|seg| {
 689                         match seg.args.as_ref().map(|generic_arg| &**generic_arg) {
 690                             None => false,
 691                             Some(&ast::GenericArgs::AngleBracketed(ref data)) => {
 692                                 let types = data.args.iter().filter_map(|arg| match arg {
 693                                     ast::GenericArg::Type(ty) => Some(ty),
 694                                     _ => None,
 695                                 });
 696                                 any_involves_impl_trait(types.into_iter()) ||
 697                                 any_involves_impl_trait(data.bindings.iter().map(|b| &b.ty))
 698                             },
 699                             Some(&ast::GenericArgs::Parenthesized(ref data)) => {
 700                                 any_involves_impl_trait(data.inputs.iter()) ||
 701                                 any_involves_impl_trait(data.output.iter())
 702                             }
 703                         }
 704                     }),
 705                     _ => false,
 706                 }
 707             }
 708
 709             fn any_involves_impl_trait<'a, I: Iterator<Item = &'a P<ast::Ty>>>(mut it: I) -> bool {
 710                 it.any(|subty| involves_impl_trait(subty))
 711             }
 712
 713             involves_impl_trait(ty)
 714         } else {
 715             false
 716         }
 717     }
 718 }
 719
 720 impl<'a> fold::Folder for ReplaceBodyWithLoop<'a> {
 721     fn fold_item_kind(&mut self, i: ast::ItemKind) -> ast::ItemKind {
 722         let is_const = match i {
 723             ast::ItemKind::Static(..) | ast::ItemKind::Const(..) => true,
 724             ast::ItemKind::Fn(ref decl, ref header, _, _) =>
 725                 header.constness.node == ast::Constness::Const || Self::should_ignore_fn(decl),
 726             _ => false,
 727         };
 728         self.run(is_const, |s| fold::noop_fold_item_kind(i, s))
 729     }
 730
 731     fn fold_trait_item(&mut self, i: ast::TraitItem) -> SmallVec<[ast::TraitItem; 1]> {
 732         let is_const = match i.node {
 733             ast::TraitItemKind::Const(..) => true,
 734             ast::TraitItemKind::Method(ast::MethodSig { ref decl, ref header, .. }, _) =>
 735                 header.constness.node == ast::Constness::Const || Self::should_ignore_fn(decl),
 736             _ => false,
 737         };
 738         self.run(is_const, |s| fold::noop_fold_trait_item(i, s))
 739     }
 740
 741     fn fold_impl_item(&mut self, i: ast::ImplItem) -> SmallVec<[ast::ImplItem; 1]> {
 742         let is_const = match i.node {
 743             ast::ImplItemKind::Const(..) => true,
 744             ast::ImplItemKind::Method(ast::MethodSig { ref decl, ref header, .. }, _) =>
 745                 header.constness.node == ast::Constness::Const || Self::should_ignore_fn(decl),
 746             _ => false,
 747         };
 748         self.run(is_const, |s| fold::noop_fold_impl_item(i, s))
 749     }
 750
 751     fn fold_anon_const(&mut self, c: ast::AnonConst) -> ast::AnonConst {
 752         self.run(true, |s| fold::noop_fold_anon_const(c, s))
 753     }
 754
 755     fn fold_block(&mut self, b: P<ast::Block>) -> P<ast::Block> {
 756         fn stmt_to_block(rules: ast::BlockCheckMode,
 757                          recovered: bool,
 758                          s: Option<ast::Stmt>,
 759                          sess: &Session) -> ast::Block {
 760             ast::Block {
 761                 stmts: s.into_iter().collect(),
 762                 rules,
 763                 id: sess.next_node_id(),
 764                 span: syntax_pos::DUMMY_SP,
 765                 recovered,
 766             }
 767         }
 768
 769         fn block_to_stmt(b: ast::Block, sess: &Session) -> ast::Stmt {
 770             let expr = P(ast::Expr {
 771                 id: sess.next_node_id(),
 772                 node: ast::ExprKind::Block(P(b), None),
 773                 span: syntax_pos::DUMMY_SP,
 774                 attrs: ThinVec::new(),
 775             });
 776
 777             ast::Stmt {
 778                 id: sess.next_node_id(),
 779                 node: ast::StmtKind::Expr(expr),
 780                 span: syntax_pos::DUMMY_SP,
 781             }
 782         }
 783
 784         let empty_block = stmt_to_block(BlockCheckMode::Default, false, None, self.sess);
 785         let loop_expr = P(ast::Expr {
 786             node: ast::ExprKind::Loop(P(empty_block), None),
 787             id: self.sess.next_node_id(),
 788             span: syntax_pos::DUMMY_SP,
 789                 attrs: ThinVec::new(),
 790         });
 791
 792         let loop_stmt = ast::Stmt {
 793             id: self.sess.next_node_id(),
 794             span: syntax_pos::DUMMY_SP,
 795             node: ast::StmtKind::Expr(loop_expr),
 796         };
 797
 798         if self.within_static_or_const {
 799             fold::noop_fold_block(b, self)
 800         } else {
 801             b.map(|b| {
 802                 let mut stmts = vec![];
 803                 for s in b.stmts {
 804                     let old_blocks = self.nested_blocks.replace(vec![]);
 805
 806                     stmts.extend(self.fold_stmt(s).into_iter().filter(|s| s.is_item()));
 807
 808                     // we put a Some in there earlier with that replace(), so this is valid
 809                     let new_blocks = self.nested_blocks.take().unwrap();
 810                     self.nested_blocks = old_blocks;
 811                     stmts.extend(new_blocks.into_iter().map(|b| block_to_stmt(b, &self.sess)));
 812                 }
 813
 814                 let mut new_block = ast::Block {
 815                     stmts,
 816                     ..b
 817                 };
 818
 819                 if let Some(old_blocks) = self.nested_blocks.as_mut() {
 820                     //push our fresh block onto the cache and yield an empty block with `loop {}`
 821                     if !new_block.stmts.is_empty() {
 822                         old_blocks.push(new_block);
 823                     }
 824
 825                     stmt_to_block(b.rules, b.recovered, Some(loop_stmt), self.sess)
 826                 } else {
 827                     //push `loop {}` onto the end of our fresh block and yield that
 828                     new_block.stmts.push(loop_stmt);
 829
 830                     new_block
 831                 }
 832             })
 833         }
 834     }
 835
 836     // in general the pretty printer processes unexpanded code, so
 837     // we override the default `fold_mac` method which panics.
 838     fn fold_mac(&mut self, mac: ast::Mac) -> ast::Mac {
 839         fold::noop_fold_mac(mac, self)
 840     }
 841 }
 842
 843 fn print_flowgraph<'a, 'tcx, W: Write>(variants: Vec<borrowck_dot::Variant>,
 844                                        tcx: TyCtxt<'a, 'tcx, 'tcx>,
 845                                        code: blocks::Code<'tcx>,
 846                                        mode: PpFlowGraphMode,
 847                                        mut out: W)
 848                                        -> io::Result<()> {
 849     let body_id = match code {
 850         blocks::Code::Expr(expr) => {
 851             // Find the function this expression is from.
 852             let mut node_id = expr.id;
 853             loop {
 854                 let node = tcx.hir.get(node_id);
 855                 if let Some(n) = hir::map::blocks::FnLikeNode::from_node(node) {
 856                     break n.body();
 857                 }
 858                 let parent = tcx.hir.get_parent_node(node_id);
 859                 assert_ne!(node_id, parent);
 860                 node_id = parent;
 861             }
 862         }
 863         blocks::Code::FnLike(fn_like) => fn_like.body(),
 864     };
 865     let body = tcx.hir.body(body_id);
 866     let cfg = cfg::CFG::new(tcx, &body);
 867     let labelled_edges = mode != PpFlowGraphMode::UnlabelledEdges;
 868     let lcfg = LabelledCFG {
 869         tcx,
 870         cfg: &cfg,
 871         name: format!("node_{}", code.id()),
 872         labelled_edges,
 873     };
 874
 875     match code {
 876         _ if variants.is_empty() => {
 877             let r = dot::render(&lcfg, &mut out);
 878             return expand_err_details(r);
 879         }
 880         blocks::Code::Expr(_) => {
 881             tcx.sess.err("--pretty flowgraph with -Z flowgraph-print annotations requires \
 882                           fn-like node id.");
 883             return Ok(());
 884         }
 885         blocks::Code::FnLike(fn_like) => {
 886             let (bccx, analysis_data) =
 887                 borrowck::build_borrowck_dataflow_data_for_fn(tcx, fn_like.body(), &cfg);
 888
 889             let lcfg = borrowck_dot::DataflowLabeller {
 890                 inner: lcfg,
 891                 variants,
 892                 borrowck_ctxt: &bccx,
 893                 analysis_data: &analysis_data,
 894             };
 895             let r = dot::render(&lcfg, &mut out);
 896             return expand_err_details(r);
 897         }
 898     }
 899
 900     fn expand_err_details(r: io::Result<()>) -> io::Result<()> {
 901         r.map_err(|ioerr| {
 902             io::Error::new(io::ErrorKind::Other,
 903                            format!("graphviz::render failed: {}", ioerr))
 904         })
 905     }
 906 }
 907
 908 pub fn fold_crate(sess: &Session, krate: ast::Crate, ppm: PpMode) -> ast::Crate {
 909     if let PpmSource(PpmEveryBodyLoops) = ppm {
 910         let mut fold = ReplaceBodyWithLoop::new(sess);
 911         fold.fold_crate(krate)
 912     } else {
 913         krate
 914     }
 915 }
 916
 917 fn get_source(input: &Input, sess: &Session) -> (Vec<u8>, FileName) {
 918     let src_name = driver::source_name(input);
 919     let src = sess.source_map()
 920         .get_source_file(&src_name)
 921         .unwrap()
 922         .src
 923         .as_ref()
 924         .unwrap()
 925         .as_bytes()
 926         .to_vec();
 927     (src, src_name)
 928 }
 929
 930 fn write_output(out: Vec<u8>, ofile: Option<&Path>) {
 931     match ofile {
 932         None => print!("{}", String::from_utf8(out).unwrap()),
 933         Some(p) => {
 934             match File::create(p) {
 935                 Ok(mut w) => w.write_all(&out).unwrap(),
 936                 Err(e) => panic!("print-print failed to open {} due to {}", p.display(), e),
 937             }
 938         }
 939     }
 940 }
 941
 942 pub fn print_after_parsing(sess: &Session,
 943                            input: &Input,
 944                            krate: &ast::Crate,
 945                            ppm: PpMode,
 946                            ofile: Option<&Path>) {
 947     let (src, src_name) = get_source(input, sess);
 948
 949     let mut rdr = &*src;
 950     let mut out = Vec::new();
 951
 952     if let PpmSource(s) = ppm {
 953         // Silently ignores an identified node.
 954         let out: &mut dyn Write = &mut out;
 955         s.call_with_pp_support(sess, None, move |annotation| {
 956             debug!("pretty printing source code {:?}", s);
 957             let sess = annotation.sess();
 958             pprust::print_crate(sess.source_map(),
 959                                 &sess.parse_sess,
 960                                 krate,
 961                                 src_name,
 962                                 &mut rdr,
 963                                 box out,
 964                                 annotation.pp_ann(),
 965                                 false)
 966         }).unwrap()
 967     } else {
 968         unreachable!();
 969     };
 970
 971     write_output(out, ofile);
 972 }
 973
 974 pub fn print_after_hir_lowering<'tcx, 'a: 'tcx>(sess: &'a Session,
 975                                                 cstore: &'tcx CStore,
 976                                                 hir_map: &hir_map::Map<'tcx>,
 977                                                 analysis: &ty::CrateAnalysis,
 978                                                 resolutions: &Resolutions,
 979                                                 input: &Input,
 980                                                 krate: &ast::Crate,
 981                                                 crate_name: &str,
 982                                                 ppm: PpMode,
 983                                                 arenas: &'tcx AllArenas<'tcx>,
 984                                                 output_filenames: &OutputFilenames,
 985                                                 opt_uii: Option<UserIdentifiedItem>,
 986                                                 ofile: Option<&Path>) {
 987     if ppm.needs_analysis() {
 988         print_with_analysis(sess,
 989                             cstore,
 990                             hir_map,
 991                             analysis,
 992                             resolutions,
 993                             crate_name,
 994                             arenas,
 995                             output_filenames,
 996                             ppm,
 997                             opt_uii,
 998                             ofile);
 999         return;
1000     }
1001
1002     let (src, src_name) = get_source(input, sess);
1003
1004     let mut rdr = &src[..];
1005     let mut out = Vec::new();
1006
1007     match (ppm, opt_uii) {
1008             (PpmSource(s), _) => {
1009                 // Silently ignores an identified node.
1010                 let out: &mut dyn Write = &mut out;
1011                 s.call_with_pp_support(sess, Some(hir_map), move |annotation| {
1012                     debug!("pretty printing source code {:?}", s);
1013                     let sess = annotation.sess();
1014                     pprust::print_crate(sess.source_map(),
1015                                         &sess.parse_sess,
1016                                         krate,
1017                                         src_name,
1018                                         &mut rdr,
1019                                         box out,
1020                                         annotation.pp_ann(),
1021                                         true)
1022                 })
1023             }
1024
1025             (PpmHir(s), None) => {
1026                 let out: &mut dyn Write = &mut out;
1027                 s.call_with_pp_support_hir(sess,
1028                                            cstore,
1029                                            hir_map,
1030                                            analysis,
1031                                            resolutions,
1032                                            arenas,
1033                                            output_filenames,
1034                                            crate_name,
1035                                            move |annotation, krate| {
1036                     debug!("pretty printing source code {:?}", s);
1037                     let sess = annotation.sess();
1038                     pprust_hir::print_crate(sess.source_map(),
1039                                             &sess.parse_sess,
1040                                             krate,
1041                                             src_name,
1042                                             &mut rdr,
1043                                             box out,
1044                                             annotation.pp_ann(),
1045                                             true)
1046                 })
1047             }
1048
1049             (PpmHirTree(s), None) => {
1050                 let out: &mut dyn Write = &mut out;
1051                 s.call_with_pp_support_hir(sess,
1052                                            cstore,
1053                                            hir_map,
1054                                            analysis,
1055                                            resolutions,
1056                                            arenas,
1057                                            output_filenames,
1058                                            crate_name,
1059                                            move |_annotation, krate| {
1060                     debug!("pretty printing source code {:?}", s);
1061                     write!(out, "{:#?}", krate)
1062                 })
1063             }
1064
1065             (PpmHir(s), Some(uii)) => {
1066                 let out: &mut dyn Write = &mut out;
1067                 s.call_with_pp_support_hir(sess,
1068                                            cstore,
1069                                            hir_map,
1070                                            analysis,
1071                                            resolutions,
1072                                            arenas,
1073                                            output_filenames,
1074                                            crate_name,
1075                                            move |annotation, _| {
1076                     debug!("pretty printing source code {:?}", s);
1077                     let sess = annotation.sess();
1078                     let hir_map = annotation.hir_map().expect("-Z unpretty missing HIR map");
1079                     let mut pp_state = pprust_hir::State::new_from_input(sess.source_map(),
1080                                                                          &sess.parse_sess,
1081                                                                          src_name,
1082                                                                          &mut rdr,
1083                                                                          box out,
1084                                                                          annotation.pp_ann(),
1085                                                                          true);
1086                     for node_id in uii.all_matching_node_ids(hir_map) {
1087                         let node = hir_map.get(node_id);
1088                         pp_state.print_node(node)?;
1089                         pp_state.s.space()?;
1090                         let path = annotation.node_path(node_id)
1091                             .expect("-Z unpretty missing node paths");
1092                         pp_state.synth_comment(path)?;
1093                         pp_state.s.hardbreak()?;
1094                     }
1095                     pp_state.s.eof()
1096                 })
1097             }
1098
1099             (PpmHirTree(s), Some(uii)) => {
1100                 let out: &mut dyn Write = &mut out;
1101                 s.call_with_pp_support_hir(sess,
1102                                            cstore,
1103                                            hir_map,
1104                                            analysis,
1105                                            resolutions,
1106                                            arenas,
1107                                            output_filenames,
1108                                            crate_name,
1109                                            move |_annotation, _krate| {
1110                     debug!("pretty printing source code {:?}", s);
1111                     for node_id in uii.all_matching_node_ids(hir_map) {
1112                         let node = hir_map.get(node_id);
1113                         write!(out, "{:#?}", node)?;
1114                     }
1115                     Ok(())
1116                 })
1117             }
1118
1119             _ => unreachable!(),
1120         }
1121         .unwrap();
1122
1123     write_output(out, ofile);
1124 }
1125
1126 // In an ideal world, this would be a public function called by the driver after
1127 // analsysis is performed. However, we want to call `phase_3_run_analysis_passes`
1128 // with a different callback than the standard driver, so that isn't easy.
1129 // Instead, we call that function ourselves.
1130 fn print_with_analysis<'tcx, 'a: 'tcx>(sess: &'a Session,
1131                                        cstore: &'a CStore,
1132                                        hir_map: &hir_map::Map<'tcx>,
1133                                        analysis: &ty::CrateAnalysis,
1134                                        resolutions: &Resolutions,
1135                                        crate_name: &str,
1136                                        arenas: &'tcx AllArenas<'tcx>,
1137                                        output_filenames: &OutputFilenames,
1138                                        ppm: PpMode,
1139                                        uii: Option<UserIdentifiedItem>,
1140                                        ofile: Option<&Path>) {
1141     let nodeid = if let Some(uii) = uii {
1142         debug!("pretty printing for {:?}", uii);
1143         Some(uii.to_one_node_id("-Z unpretty", sess, &hir_map))
1144     } else {
1145         debug!("pretty printing for whole crate");
1146         None
1147     };
1148
1149     let mut out = Vec::new();
1150
1151     let control = &driver::CompileController::basic();
1152     let codegen_backend = ::get_codegen_backend(sess);
1153     abort_on_err(driver::phase_3_run_analysis_passes(&*codegen_backend,
1154                                                      control,
1155                                                      sess,
1156                                                      cstore,
1157                                                      hir_map.clone(),
1158                                                      analysis.clone(),
1159                                                      resolutions.clone(),
1160                                                      arenas,
1161                                                      crate_name,
1162                                                      output_filenames,
1163                                                      |tcx, _, _, _| {
1164         match ppm {
1165             PpmMir | PpmMirCFG => {
1166                 if let Some(nodeid) = nodeid {
1167                     let def_id = tcx.hir.local_def_id(nodeid);
1168                     match ppm {
1169                         PpmMir => write_mir_pretty(tcx, Some(def_id), &mut out),
1170                         PpmMirCFG => write_mir_graphviz(tcx, Some(def_id), &mut out),
1171                         _ => unreachable!(),
1172                     }?;
1173                 } else {
1174                     match ppm {
1175                         PpmMir => write_mir_pretty(tcx, None, &mut out),
1176                         PpmMirCFG => write_mir_graphviz(tcx, None, &mut out),
1177                         _ => unreachable!(),
1178                     }?;
1179                 }
1180                 Ok(())
1181             }
1182             PpmFlowGraph(mode) => {
1183                 let nodeid =
1184                     nodeid.expect("`pretty flowgraph=..` needs NodeId (int) or unique path \
1185                                    suffix (b::c::d)");
1186                 let node = tcx.hir.find(nodeid).unwrap_or_else(|| {
1187                     tcx.sess.fatal(&format!("--pretty flowgraph couldn't find id: {}", nodeid))
1188                 });
1189
1190                 match blocks::Code::from_node(&tcx.hir, nodeid) {
1191                     Some(code) => {
1192                         let variants = gather_flowgraph_variants(tcx.sess);
1193
1194                         let out: &mut dyn Write = &mut out;
1195
1196                         print_flowgraph(variants, tcx, code, mode, out)
1197                     }
1198                     None => {
1199                         let message = format!("--pretty=flowgraph needs block, fn, or method; \
1200                                                got {:?}",
1201                                               node);
1202
1203                         tcx.sess.span_fatal(tcx.hir.span(nodeid), &message)
1204                     }
1205                 }
1206             }
1207             _ => unreachable!(),
1208         }
1209     }),
1210                  sess)
1211         .unwrap();
1212
1213     write_output(out, ofile);
1214 }