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