1 use rustc::hir::def_id::{DefId, LOCAL_CRATE};
3 use rustc::mir::visit::Visitor;
4 use rustc::ty::{self, TyCtxt};
5 use rustc_data_structures::fx::FxHashMap;
6 use rustc_data_structures::indexed_vec::Idx;
8 use std::fmt::Write as _;
10 use std::io::{self, Write};
11 use std::path::{Path, PathBuf};
12 use super::graphviz::write_mir_fn_graphviz;
13 use crate::transform::MirSource;
15 const INDENT: &str = " ";
16 /// Alignment for lining up comments following MIR statements
17 pub(crate) const ALIGN: usize = 40;
19 /// An indication of where we are in the control flow graph. Used for printing
20 /// extra information in `dump_mir`
22 /// We have not started dumping the control flow graph, but we are about to.
25 /// We just finished dumping the control flow graph. This is right before EOF
28 /// We are about to start dumping the given basic block.
29 BeforeBlock(BasicBlock),
31 /// We are just about to dump the given statement or terminator.
32 BeforeLocation(Location),
34 /// We just dumped the given statement or terminator.
35 AfterLocation(Location),
37 /// We just dumped the terminator for a block but not the closing `}`.
38 AfterTerminator(BasicBlock),
41 /// If the session is properly configured, dumps a human-readable
42 /// representation of the mir into:
45 /// rustc.node<node_id>.<pass_num>.<pass_name>.<disambiguator>
48 /// Output from this function is controlled by passing `-Z dump-mir=<filter>`,
49 /// where `<filter>` takes the following forms:
51 /// - `all` -- dump MIR for all fns, all passes, all everything
52 /// - a filter defined by a set of substrings combined with `&` and `|`
53 /// (`&` has higher precedence). At least one of the `|`-separated groups
54 /// must match; an `|`-separated group matches if all of its `&`-separated
55 /// substrings are matched.
59 /// - `nll` == match if `nll` appears in the name
60 /// - `foo & nll` == match if `foo` and `nll` both appear in the name
61 /// - `foo & nll | typeck` == match if `foo` and `nll` both appear in the name
62 /// or `typeck` appears in the name.
63 /// - `foo & nll | bar & typeck` == match if `foo` and `nll` both appear in the name
64 /// or `typeck` and `bar` both appear in the name.
65 pub fn dump_mir<'a, 'gcx, 'tcx, F>(
66 tcx: TyCtxt<'a, 'gcx, 'tcx>,
67 pass_num: Option<&dyn Display>,
69 disambiguator: &dyn Display,
70 source: MirSource<'tcx>,
74 F: FnMut(PassWhere, &mut dyn Write) -> io::Result<()>,
76 if !dump_enabled(tcx, pass_name, source) {
80 let node_path = ty::print::with_forced_impl_filename_line(|| {
81 // see notes on #41697 below
82 tcx.def_path_str(source.def_id())
84 dump_matched_mir_node(
96 pub fn dump_enabled<'a, 'gcx, 'tcx>(
97 tcx: TyCtxt<'a, 'gcx, 'tcx>,
99 source: MirSource<'tcx>,
101 let filters = match tcx.sess.opts.debugging_opts.dump_mir {
102 None => return false,
103 Some(ref filters) => filters,
105 let node_path = ty::print::with_forced_impl_filename_line(|| {
106 // see notes on #41697 below
107 tcx.def_path_str(source.def_id())
109 filters.split('|').any(|or_filter| {
110 or_filter.split('&').all(|and_filter| {
111 and_filter == "all" || pass_name.contains(and_filter) || node_path.contains(and_filter)
116 // #41697 -- we use `with_forced_impl_filename_line()` because
117 // `def_path_str()` would otherwise trigger `type_of`, and this can
118 // run while we are already attempting to evaluate `type_of`.
120 fn dump_matched_mir_node<'a, 'gcx, 'tcx, F>(
121 tcx: TyCtxt<'a, 'gcx, 'tcx>,
122 pass_num: Option<&dyn Display>,
125 disambiguator: &dyn Display,
126 source: MirSource<'tcx>,
130 F: FnMut(PassWhere, &mut dyn Write) -> io::Result<()>,
132 let _: io::Result<()> = try {
133 let mut file = create_dump_file(tcx, "mir", pass_num, pass_name, disambiguator, source)?;
134 writeln!(file, "// MIR for `{}`", node_path)?;
135 writeln!(file, "// source = {:?}", source)?;
136 writeln!(file, "// pass_name = {}", pass_name)?;
137 writeln!(file, "// disambiguator = {}", disambiguator)?;
138 if let Some(ref layout) = mir.generator_layout {
139 writeln!(file, "// generator_layout = {:?}", layout)?;
142 extra_data(PassWhere::BeforeCFG, &mut file)?;
143 write_user_type_annotations(mir, &mut file)?;
144 write_mir_fn(tcx, source, mir, &mut extra_data, &mut file)?;
145 extra_data(PassWhere::AfterCFG, &mut file)?;
148 if tcx.sess.opts.debugging_opts.dump_mir_graphviz {
149 let _: io::Result<()> = try {
151 create_dump_file(tcx, "dot", pass_num, pass_name, disambiguator, source)?;
152 write_mir_fn_graphviz(tcx, source.def_id(), mir, &mut file)?;
157 /// Returns the path to the filename where we should dump a given MIR.
158 /// Also used by other bits of code (e.g., NLL inference) that dump
159 /// graphviz data or other things.
161 tcx: TyCtxt<'_, '_, '_>,
163 pass_num: Option<&dyn Display>,
165 disambiguator: &dyn Display,
166 source: MirSource<'tcx>,
168 let promotion_id = match source.promoted {
169 Some(id) => format!("-{:?}", id),
170 None => String::new(),
173 let pass_num = if tcx.sess.opts.debugging_opts.dump_mir_exclude_pass_number {
177 None => ".-------".to_string(),
178 Some(pass_num) => format!(".{}", pass_num),
182 let mut file_path = PathBuf::new();
183 file_path.push(Path::new(&tcx.sess.opts.debugging_opts.dump_mir_dir));
186 .def_path(source.def_id())
187 .to_filename_friendly_no_crate();
188 // All drop shims have the same DefId, so we have to add the type
189 // to get unique file names.
190 let shim_disambiguator = match source.instance {
191 ty::InstanceDef::DropGlue(_, Some(ty)) => {
192 // Unfortunately, pretty-printed typed are not very filename-friendly.
193 // We dome some filtering.
194 let mut s = ".".to_owned();
195 s.extend(ty.to_string()
197 .filter_map(|c| match c {
199 ':' | '<' | '>' => Some('_'),
207 let file_name = format!(
208 "rustc.{}{}{}{}.{}.{}.{}",
218 file_path.push(&file_name);
223 /// Attempts to open a file where we should dump a given MIR or other
224 /// bit of MIR-related data. Used by `mir-dump`, but also by other
225 /// bits of code (e.g., NLL inference) that dump graphviz data or
226 /// other things, and hence takes the extension as an argument.
227 pub(crate) fn create_dump_file(
228 tcx: TyCtxt<'_, '_, '_>,
230 pass_num: Option<&dyn Display>,
232 disambiguator: &dyn Display,
233 source: MirSource<'tcx>,
234 ) -> io::Result<fs::File> {
235 let file_path = dump_path(tcx, extension, pass_num, pass_name, disambiguator, source);
236 if let Some(parent) = file_path.parent() {
237 fs::create_dir_all(parent)?;
239 fs::File::create(&file_path)
242 /// Write out a human-readable textual representation for the given MIR.
243 pub fn write_mir_pretty<'a, 'gcx, 'tcx>(
244 tcx: TyCtxt<'a, 'gcx, 'tcx>,
245 single: Option<DefId>,
247 ) -> io::Result<()> {
250 "// WARNING: This output format is intended for human consumers only"
254 "// and is subject to change without notice. Knock yourself out."
257 let mut first = true;
258 for def_id in dump_mir_def_ids(tcx, single) {
259 let mir = &tcx.optimized_mir(def_id);
264 // Put empty lines between all items
268 write_mir_fn(tcx, MirSource::item(def_id), mir, &mut |_, _| Ok(()), w)?;
270 for (i, mir) in mir.promoted.iter_enumerated() {
272 let src = MirSource {
273 instance: ty::InstanceDef::Item(def_id),
276 write_mir_fn(tcx, src, mir, &mut |_, _| Ok(()), w)?;
282 pub fn write_mir_fn<'a, 'gcx, 'tcx, F>(
283 tcx: TyCtxt<'a, 'gcx, 'tcx>,
284 src: MirSource<'tcx>,
290 F: FnMut(PassWhere, &mut dyn Write) -> io::Result<()>,
292 write_mir_intro(tcx, src, mir, w)?;
293 for block in mir.basic_blocks().indices() {
294 extra_data(PassWhere::BeforeBlock(block), w)?;
295 write_basic_block(tcx, block, mir, extra_data, w)?;
296 if block.index() + 1 != mir.basic_blocks().len() {
305 /// Write out a human-readable textual representation for the given basic block.
306 pub fn write_basic_block<'cx, 'gcx, 'tcx, F>(
307 tcx: TyCtxt<'cx, 'gcx, 'tcx>,
314 F: FnMut(PassWhere, &mut dyn Write) -> io::Result<()>,
316 let data = &mir[block];
318 // Basic block label at the top.
319 let cleanup_text = if data.is_cleanup { " (cleanup)" } else { "" };
320 writeln!(w, "{}{:?}{}: {{", INDENT, block, cleanup_text)?;
322 // List of statements in the middle.
323 let mut current_location = Location {
327 for statement in &data.statements {
328 extra_data(PassWhere::BeforeLocation(current_location), w)?;
329 let indented_mir = format!("{0}{0}{1:?};", INDENT, statement);
335 comment(tcx, statement.source_info),
339 write_extra(tcx, w, |visitor| {
340 visitor.visit_statement(current_location.block, statement, current_location);
343 extra_data(PassWhere::AfterLocation(current_location), w)?;
345 current_location.statement_index += 1;
348 // Terminator at the bottom.
349 extra_data(PassWhere::BeforeLocation(current_location), w)?;
350 let indented_terminator = format!("{0}{0}{1:?};", INDENT, data.terminator().kind);
356 comment(tcx, data.terminator().source_info),
360 write_extra(tcx, w, |visitor| {
361 visitor.visit_terminator(current_location.block, data.terminator(), current_location);
364 extra_data(PassWhere::AfterLocation(current_location), w)?;
365 extra_data(PassWhere::AfterTerminator(block), w)?;
367 writeln!(w, "{}}}", INDENT)
370 /// After we print the main statement, we sometimes dump extra
371 /// information. There's often a lot of little things "nuzzled up" in
373 fn write_extra<'cx, 'gcx, 'tcx, F>(
374 tcx: TyCtxt<'cx, 'gcx, 'tcx>,
375 write: &mut dyn Write,
379 F: FnMut(&mut ExtraComments<'cx, 'gcx, 'tcx>),
381 let mut extra_comments = ExtraComments {
385 visit_op(&mut extra_comments);
386 for comment in extra_comments.comments {
387 writeln!(write, "{:A$} // {}", "", comment, A = ALIGN)?;
392 struct ExtraComments<'cx, 'gcx: 'tcx, 'tcx: 'cx> {
393 _tcx: TyCtxt<'cx, 'gcx, 'tcx>, // don't need it now, but bet we will soon
394 comments: Vec<String>,
397 impl<'cx, 'gcx, 'tcx> ExtraComments<'cx, 'gcx, 'tcx> {
398 fn push(&mut self, lines: &str) {
399 for line in lines.split('\n') {
400 self.comments.push(line.to_string());
405 impl<'cx, 'gcx, 'tcx> Visitor<'tcx> for ExtraComments<'cx, 'gcx, 'tcx> {
406 fn visit_constant(&mut self, constant: &Constant<'tcx>, location: Location) {
407 self.super_constant(constant, location);
408 let Constant { span, ty, user_ty, literal } = constant;
409 self.push("mir::Constant");
410 self.push(&format!("+ span: {:?}", span));
411 self.push(&format!("+ ty: {:?}", ty));
412 if let Some(user_ty) = user_ty {
413 self.push(&format!("+ user_ty: {:?}", user_ty));
415 self.push(&format!("+ literal: {:?}", literal));
418 fn visit_const(&mut self, constant: &&'tcx ty::Const<'tcx>, _: Location) {
419 self.super_const(constant);
420 let ty::Const { ty, val, .. } = constant;
421 self.push("ty::Const");
422 self.push(&format!("+ ty: {:?}", ty));
423 self.push(&format!("+ val: {:?}", val));
426 fn visit_rvalue(&mut self, rvalue: &Rvalue<'tcx>, location: Location) {
427 self.super_rvalue(rvalue, location);
429 Rvalue::Aggregate(kind, _) => match **kind {
430 AggregateKind::Closure(def_id, substs) => {
431 self.push("closure");
432 self.push(&format!("+ def_id: {:?}", def_id));
433 self.push(&format!("+ substs: {:#?}", substs));
436 AggregateKind::Generator(def_id, substs, movability) => {
437 self.push("generator");
438 self.push(&format!("+ def_id: {:?}", def_id));
439 self.push(&format!("+ substs: {:#?}", substs));
440 self.push(&format!("+ movability: {:?}", movability));
443 AggregateKind::Adt(_, _, _, Some(user_ty), _) => {
445 self.push(&format!("+ user_ty: {:?}", user_ty));
456 fn comment(tcx: TyCtxt<'_, '_, '_>, SourceInfo { span, scope }: SourceInfo) -> String {
460 tcx.sess.source_map().span_to_string(span)
464 /// Prints user-defined variables in a scope tree.
466 /// Returns the total number of variables printed.
468 tcx: TyCtxt<'_, '_, '_>,
470 scope_tree: &FxHashMap<SourceScope, Vec<SourceScope>>,
474 ) -> io::Result<()> {
475 let indent = depth * INDENT.len();
477 let children = match scope_tree.get(&parent) {
478 Some(children) => children,
479 None => return Ok(()),
482 for &child in children {
483 let data = &mir.source_scopes[child];
484 assert_eq!(data.parent_scope, Some(parent));
485 writeln!(w, "{0:1$}scope {2} {{", "", indent, child.index())?;
487 // User variable types (including the user's name in a comment).
488 for local in mir.vars_iter() {
489 let var = &mir.local_decls[local];
490 let (name, source_info) = if var.source_info.scope == child {
491 (var.name.unwrap(), var.source_info)
493 // Not a variable or not declared in this scope.
497 let mut_str = if var.mutability == Mutability::Mut {
503 let indent = indent + INDENT.len();
504 let mut indented_var = format!(
505 "{0:1$}let {2}{3:?}: {4:?}",
512 for user_ty in var.user_ty.projections() {
513 write!(indented_var, " as {:?}", user_ty).unwrap();
515 indented_var.push_str(";");
518 "{0:1$} // \"{2}\" in {3}",
522 comment(tcx, source_info)
526 write_scope_tree(tcx, mir, scope_tree, w, child, depth + 1)?;
528 writeln!(w, "{0:1$}}}", "", depth * INDENT.len())?;
534 /// Write out a human-readable textual representation of the MIR's `fn` type and the types of its
535 /// local variables (both user-defined bindings and compiler temporaries).
536 pub fn write_mir_intro<'a, 'gcx, 'tcx>(
537 tcx: TyCtxt<'a, 'gcx, 'tcx>,
538 src: MirSource<'tcx>,
541 ) -> io::Result<()> {
542 write_mir_sig(tcx, src, mir, w)?;
545 // construct a scope tree and write it out
546 let mut scope_tree: FxHashMap<SourceScope, Vec<SourceScope>> = Default::default();
547 for (index, scope_data) in mir.source_scopes.iter().enumerate() {
548 if let Some(parent) = scope_data.parent_scope {
552 .push(SourceScope::new(index));
554 // Only the argument scope has no parent, because it's the root.
555 assert_eq!(index, OUTERMOST_SOURCE_SCOPE.index());
559 // Print return place
560 let indented_retptr = format!("{}let mut {:?}: {};",
563 mir.local_decls[RETURN_PLACE].ty);
564 writeln!(w, "{0:1$} // return place",
568 write_scope_tree(tcx, mir, &scope_tree, w, OUTERMOST_SOURCE_SCOPE, 1)?;
570 write_temp_decls(mir, w)?;
572 // Add an empty line before the first block is printed.
579 tcx: TyCtxt<'_, '_, '_>,
580 src: MirSource<'tcx>,
583 ) -> io::Result<()> {
584 use rustc::hir::def::Def;
586 trace!("write_mir_sig: {:?}", src.instance);
587 let descr = tcx.describe_def(src.def_id());
588 let is_function = match descr {
589 Some(Def::Fn(_)) | Some(Def::Method(_)) | Some(Def::Ctor(..)) => true,
590 _ => tcx.is_closure(src.def_id()),
592 match (descr, src.promoted) {
593 (_, Some(i)) => write!(w, "{:?} in ", i)?,
594 (Some(Def::Const(_)), _) | (Some(Def::AssociatedConst(_)), _) => write!(w, "const ")?,
595 (Some(Def::Static(_, /*is_mutbl*/false)), _) => write!(w, "static ")?,
596 (Some(Def::Static(_, /*is_mutbl*/true)), _) => write!(w, "static mut ")?,
597 (_, _) if is_function => write!(w, "fn ")?,
598 (None, _) => {}, // things like anon const, not an item
599 _ => bug!("Unexpected def description {:?}", descr),
602 ty::print::with_forced_impl_filename_line(|| {
603 // see notes on #41697 elsewhere
604 write!(w, " {}", tcx.def_path_str(src.def_id()))
607 if src.promoted.is_none() && is_function {
610 // fn argument types.
611 for (i, arg) in mir.args_iter().enumerate() {
615 write!(w, "{:?}: {}", Place::Base(PlaceBase::Local(arg)), mir.local_decls[arg].ty)?;
618 write!(w, ") -> {}", mir.return_ty())?;
620 assert_eq!(mir.arg_count, 0);
621 write!(w, ": {} =", mir.return_ty())?;
624 if let Some(yield_ty) = mir.yield_ty {
626 writeln!(w, "yields {}", yield_ty)?;
630 // Next thing that gets printed is the opening {
635 fn write_temp_decls(mir: &Mir<'_>, w: &mut dyn Write) -> io::Result<()> {
636 // Compiler-introduced temporary types.
637 for temp in mir.temps_iter() {
642 if mir.local_decls[temp].mutability == Mutability::Mut {"mut "} else {""},
644 mir.local_decls[temp].ty
651 fn write_user_type_annotations(mir: &Mir<'_>, w: &mut dyn Write) -> io::Result<()> {
652 if !mir.user_type_annotations.is_empty() {
653 writeln!(w, "| User Type Annotations")?;
655 for (index, annotation) in mir.user_type_annotations.iter_enumerated() {
656 writeln!(w, "| {:?}: {:?} at {:?}", index.index(), annotation.user_ty, annotation.span)?;
658 if !mir.user_type_annotations.is_empty() {
664 pub fn dump_mir_def_ids(tcx: TyCtxt<'_, '_, '_>, single: Option<DefId>) -> Vec<DefId> {
665 if let Some(i) = single {
668 tcx.mir_keys(LOCAL_CRATE).iter().cloned().collect()