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-rw-r--r--compiler/rustc_middle/src/mir/pretty.rs1067
1 files changed, 1067 insertions, 0 deletions
diff --git a/compiler/rustc_middle/src/mir/pretty.rs b/compiler/rustc_middle/src/mir/pretty.rs
new file mode 100644
index 000000000..0ce41337b
--- /dev/null
+++ b/compiler/rustc_middle/src/mir/pretty.rs
@@ -0,0 +1,1067 @@
+use std::collections::BTreeSet;
+use std::fmt::Display;
+use std::fmt::Write as _;
+use std::fs;
+use std::io::{self, Write};
+use std::path::{Path, PathBuf};
+
+use super::graphviz::write_mir_fn_graphviz;
+use super::spanview::write_mir_fn_spanview;
+use either::Either;
+use rustc_data_structures::fx::FxHashMap;
+use rustc_hir::def_id::DefId;
+use rustc_index::vec::Idx;
+use rustc_middle::mir::interpret::{
+ read_target_uint, AllocId, Allocation, ConstAllocation, ConstValue, GlobalAlloc, Pointer,
+ Provenance,
+};
+use rustc_middle::mir::visit::Visitor;
+use rustc_middle::mir::MirSource;
+use rustc_middle::mir::*;
+use rustc_middle::ty::{self, TyCtxt};
+use rustc_target::abi::Size;
+
+const INDENT: &str = " ";
+/// Alignment for lining up comments following MIR statements
+pub(crate) const ALIGN: usize = 40;
+
+/// An indication of where we are in the control flow graph. Used for printing
+/// extra information in `dump_mir`
+pub enum PassWhere {
+ /// We have not started dumping the control flow graph, but we are about to.
+ BeforeCFG,
+
+ /// We just finished dumping the control flow graph. This is right before EOF
+ AfterCFG,
+
+ /// We are about to start dumping the given basic block.
+ BeforeBlock(BasicBlock),
+
+ /// We are just about to dump the given statement or terminator.
+ BeforeLocation(Location),
+
+ /// We just dumped the given statement or terminator.
+ AfterLocation(Location),
+
+ /// We just dumped the terminator for a block but not the closing `}`.
+ AfterTerminator(BasicBlock),
+}
+
+/// If the session is properly configured, dumps a human-readable
+/// representation of the mir into:
+///
+/// ```text
+/// rustc.node<node_id>.<pass_num>.<pass_name>.<disambiguator>
+/// ```
+///
+/// Output from this function is controlled by passing `-Z dump-mir=<filter>`,
+/// where `<filter>` takes the following forms:
+///
+/// - `all` -- dump MIR for all fns, all passes, all everything
+/// - a filter defined by a set of substrings combined with `&` and `|`
+/// (`&` has higher precedence). At least one of the `|`-separated groups
+/// must match; an `|`-separated group matches if all of its `&`-separated
+/// substrings are matched.
+///
+/// Example:
+///
+/// - `nll` == match if `nll` appears in the name
+/// - `foo & nll` == match if `foo` and `nll` both appear in the name
+/// - `foo & nll | typeck` == match if `foo` and `nll` both appear in the name
+/// or `typeck` appears in the name.
+/// - `foo & nll | bar & typeck` == match if `foo` and `nll` both appear in the name
+/// or `typeck` and `bar` both appear in the name.
+#[inline]
+pub fn dump_mir<'tcx, F>(
+ tcx: TyCtxt<'tcx>,
+ pass_num: Option<&dyn Display>,
+ pass_name: &str,
+ disambiguator: &dyn Display,
+ body: &Body<'tcx>,
+ extra_data: F,
+) where
+ F: FnMut(PassWhere, &mut dyn Write) -> io::Result<()>,
+{
+ if !dump_enabled(tcx, pass_name, body.source.def_id()) {
+ return;
+ }
+
+ dump_matched_mir_node(tcx, pass_num, pass_name, disambiguator, body, extra_data);
+}
+
+pub fn dump_enabled<'tcx>(tcx: TyCtxt<'tcx>, pass_name: &str, def_id: DefId) -> bool {
+ let Some(ref filters) = tcx.sess.opts.unstable_opts.dump_mir else {
+ return false;
+ };
+ // see notes on #41697 below
+ let node_path = ty::print::with_forced_impl_filename_line!(tcx.def_path_str(def_id));
+ filters.split('|').any(|or_filter| {
+ or_filter.split('&').all(|and_filter| {
+ let and_filter_trimmed = and_filter.trim();
+ and_filter_trimmed == "all"
+ || pass_name.contains(and_filter_trimmed)
+ || node_path.contains(and_filter_trimmed)
+ })
+ })
+}
+
+// #41697 -- we use `with_forced_impl_filename_line()` because
+// `def_path_str()` would otherwise trigger `type_of`, and this can
+// run while we are already attempting to evaluate `type_of`.
+
+fn dump_matched_mir_node<'tcx, F>(
+ tcx: TyCtxt<'tcx>,
+ pass_num: Option<&dyn Display>,
+ pass_name: &str,
+ disambiguator: &dyn Display,
+ body: &Body<'tcx>,
+ mut extra_data: F,
+) where
+ F: FnMut(PassWhere, &mut dyn Write) -> io::Result<()>,
+{
+ let _: io::Result<()> = try {
+ let mut file =
+ create_dump_file(tcx, "mir", pass_num, pass_name, disambiguator, body.source)?;
+ // see notes on #41697 above
+ let def_path =
+ ty::print::with_forced_impl_filename_line!(tcx.def_path_str(body.source.def_id()));
+ write!(file, "// MIR for `{}", def_path)?;
+ match body.source.promoted {
+ None => write!(file, "`")?,
+ Some(promoted) => write!(file, "::{:?}`", promoted)?,
+ }
+ writeln!(file, " {} {}", disambiguator, pass_name)?;
+ if let Some(ref layout) = body.generator_layout() {
+ writeln!(file, "/* generator_layout = {:#?} */", layout)?;
+ }
+ writeln!(file)?;
+ extra_data(PassWhere::BeforeCFG, &mut file)?;
+ write_user_type_annotations(tcx, body, &mut file)?;
+ write_mir_fn(tcx, body, &mut extra_data, &mut file)?;
+ extra_data(PassWhere::AfterCFG, &mut file)?;
+ };
+
+ if tcx.sess.opts.unstable_opts.dump_mir_graphviz {
+ let _: io::Result<()> = try {
+ let mut file =
+ create_dump_file(tcx, "dot", pass_num, pass_name, disambiguator, body.source)?;
+ write_mir_fn_graphviz(tcx, body, false, &mut file)?;
+ };
+ }
+
+ if let Some(spanview) = tcx.sess.opts.unstable_opts.dump_mir_spanview {
+ let _: io::Result<()> = try {
+ let file_basename =
+ dump_file_basename(tcx, pass_num, pass_name, disambiguator, body.source);
+ let mut file = create_dump_file_with_basename(tcx, &file_basename, "html")?;
+ if body.source.def_id().is_local() {
+ write_mir_fn_spanview(tcx, body, spanview, &file_basename, &mut file)?;
+ }
+ };
+ }
+}
+
+/// Returns the file basename portion (without extension) of a filename path
+/// where we should dump a MIR representation output files.
+fn dump_file_basename<'tcx>(
+ tcx: TyCtxt<'tcx>,
+ pass_num: Option<&dyn Display>,
+ pass_name: &str,
+ disambiguator: &dyn Display,
+ source: MirSource<'tcx>,
+) -> String {
+ let promotion_id = match source.promoted {
+ Some(id) => format!("-{:?}", id),
+ None => String::new(),
+ };
+
+ let pass_num = if tcx.sess.opts.unstable_opts.dump_mir_exclude_pass_number {
+ String::new()
+ } else {
+ match pass_num {
+ None => ".-------".to_string(),
+ Some(pass_num) => format!(".{}", pass_num),
+ }
+ };
+
+ let crate_name = tcx.crate_name(source.def_id().krate);
+ let item_name = tcx.def_path(source.def_id()).to_filename_friendly_no_crate();
+ // All drop shims have the same DefId, so we have to add the type
+ // to get unique file names.
+ let shim_disambiguator = match source.instance {
+ ty::InstanceDef::DropGlue(_, Some(ty)) => {
+ // Unfortunately, pretty-printed typed are not very filename-friendly.
+ // We dome some filtering.
+ let mut s = ".".to_owned();
+ s.extend(ty.to_string().chars().filter_map(|c| match c {
+ ' ' => None,
+ ':' | '<' | '>' => Some('_'),
+ c => Some(c),
+ }));
+ s
+ }
+ _ => String::new(),
+ };
+
+ format!(
+ "{}.{}{}{}{}.{}.{}",
+ crate_name, item_name, shim_disambiguator, promotion_id, pass_num, pass_name, disambiguator,
+ )
+}
+
+/// Returns the path to the filename where we should dump a given MIR.
+/// Also used by other bits of code (e.g., NLL inference) that dump
+/// graphviz data or other things.
+fn dump_path(tcx: TyCtxt<'_>, basename: &str, extension: &str) -> PathBuf {
+ let mut file_path = PathBuf::new();
+ file_path.push(Path::new(&tcx.sess.opts.unstable_opts.dump_mir_dir));
+
+ let file_name = format!("{}.{}", basename, extension,);
+
+ file_path.push(&file_name);
+
+ file_path
+}
+
+/// Attempts to open the MIR dump file with the given name and extension.
+fn create_dump_file_with_basename(
+ tcx: TyCtxt<'_>,
+ file_basename: &str,
+ extension: &str,
+) -> io::Result<io::BufWriter<fs::File>> {
+ let file_path = dump_path(tcx, file_basename, extension);
+ if let Some(parent) = file_path.parent() {
+ fs::create_dir_all(parent).map_err(|e| {
+ io::Error::new(
+ e.kind(),
+ format!("IO error creating MIR dump directory: {:?}; {}", parent, e),
+ )
+ })?;
+ }
+ Ok(io::BufWriter::new(fs::File::create(&file_path).map_err(|e| {
+ io::Error::new(e.kind(), format!("IO error creating MIR dump file: {:?}; {}", file_path, e))
+ })?))
+}
+
+/// Attempts to open a file where we should dump a given MIR or other
+/// bit of MIR-related data. Used by `mir-dump`, but also by other
+/// bits of code (e.g., NLL inference) that dump graphviz data or
+/// other things, and hence takes the extension as an argument.
+pub fn create_dump_file<'tcx>(
+ tcx: TyCtxt<'tcx>,
+ extension: &str,
+ pass_num: Option<&dyn Display>,
+ pass_name: &str,
+ disambiguator: &dyn Display,
+ source: MirSource<'tcx>,
+) -> io::Result<io::BufWriter<fs::File>> {
+ create_dump_file_with_basename(
+ tcx,
+ &dump_file_basename(tcx, pass_num, pass_name, disambiguator, source),
+ extension,
+ )
+}
+
+/// Write out a human-readable textual representation for the given MIR.
+pub fn write_mir_pretty<'tcx>(
+ tcx: TyCtxt<'tcx>,
+ single: Option<DefId>,
+ w: &mut dyn Write,
+) -> io::Result<()> {
+ writeln!(w, "// WARNING: This output format is intended for human consumers only")?;
+ writeln!(w, "// and is subject to change without notice. Knock yourself out.")?;
+
+ let mut first = true;
+ for def_id in dump_mir_def_ids(tcx, single) {
+ if first {
+ first = false;
+ } else {
+ // Put empty lines between all items
+ writeln!(w)?;
+ }
+
+ let render_body = |w: &mut dyn Write, body| -> io::Result<()> {
+ write_mir_fn(tcx, body, &mut |_, _| Ok(()), w)?;
+
+ for body in tcx.promoted_mir(def_id) {
+ writeln!(w)?;
+ write_mir_fn(tcx, body, &mut |_, _| Ok(()), w)?;
+ }
+ Ok(())
+ };
+
+ // For `const fn` we want to render both the optimized MIR and the MIR for ctfe.
+ if tcx.is_const_fn_raw(def_id) {
+ render_body(w, tcx.optimized_mir(def_id))?;
+ writeln!(w)?;
+ writeln!(w, "// MIR FOR CTFE")?;
+ // Do not use `render_body`, as that would render the promoteds again, but these
+ // are shared between mir_for_ctfe and optimized_mir
+ write_mir_fn(tcx, tcx.mir_for_ctfe(def_id), &mut |_, _| Ok(()), w)?;
+ } else {
+ let instance_mir =
+ tcx.instance_mir(ty::InstanceDef::Item(ty::WithOptConstParam::unknown(def_id)));
+ render_body(w, instance_mir)?;
+ }
+ }
+ Ok(())
+}
+
+/// Write out a human-readable textual representation for the given function.
+pub fn write_mir_fn<'tcx, F>(
+ tcx: TyCtxt<'tcx>,
+ body: &Body<'tcx>,
+ extra_data: &mut F,
+ w: &mut dyn Write,
+) -> io::Result<()>
+where
+ F: FnMut(PassWhere, &mut dyn Write) -> io::Result<()>,
+{
+ write_mir_intro(tcx, body, w)?;
+ for block in body.basic_blocks().indices() {
+ extra_data(PassWhere::BeforeBlock(block), w)?;
+ write_basic_block(tcx, block, body, extra_data, w)?;
+ if block.index() + 1 != body.basic_blocks().len() {
+ writeln!(w)?;
+ }
+ }
+
+ writeln!(w, "}}")?;
+
+ write_allocations(tcx, body, w)?;
+
+ Ok(())
+}
+
+/// Write out a human-readable textual representation for the given basic block.
+pub fn write_basic_block<'tcx, F>(
+ tcx: TyCtxt<'tcx>,
+ block: BasicBlock,
+ body: &Body<'tcx>,
+ extra_data: &mut F,
+ w: &mut dyn Write,
+) -> io::Result<()>
+where
+ F: FnMut(PassWhere, &mut dyn Write) -> io::Result<()>,
+{
+ let data = &body[block];
+
+ // Basic block label at the top.
+ let cleanup_text = if data.is_cleanup { " (cleanup)" } else { "" };
+ writeln!(w, "{}{:?}{}: {{", INDENT, block, cleanup_text)?;
+
+ // List of statements in the middle.
+ let mut current_location = Location { block, statement_index: 0 };
+ for statement in &data.statements {
+ extra_data(PassWhere::BeforeLocation(current_location), w)?;
+ let indented_body = format!("{0}{0}{1:?};", INDENT, statement);
+ writeln!(
+ w,
+ "{:A$} // {}{}",
+ indented_body,
+ if tcx.sess.verbose() { format!("{:?}: ", current_location) } else { String::new() },
+ comment(tcx, statement.source_info, body.span),
+ A = ALIGN,
+ )?;
+
+ write_extra(tcx, w, |visitor| {
+ visitor.visit_statement(statement, current_location);
+ })?;
+
+ extra_data(PassWhere::AfterLocation(current_location), w)?;
+
+ current_location.statement_index += 1;
+ }
+
+ // Terminator at the bottom.
+ extra_data(PassWhere::BeforeLocation(current_location), w)?;
+ let indented_terminator = format!("{0}{0}{1:?};", INDENT, data.terminator().kind);
+ writeln!(
+ w,
+ "{:A$} // {}{}",
+ indented_terminator,
+ if tcx.sess.verbose() { format!("{:?}: ", current_location) } else { String::new() },
+ comment(tcx, data.terminator().source_info, body.span),
+ A = ALIGN,
+ )?;
+
+ write_extra(tcx, w, |visitor| {
+ visitor.visit_terminator(data.terminator(), current_location);
+ })?;
+
+ extra_data(PassWhere::AfterLocation(current_location), w)?;
+ extra_data(PassWhere::AfterTerminator(block), w)?;
+
+ writeln!(w, "{}}}", INDENT)
+}
+
+/// After we print the main statement, we sometimes dump extra
+/// information. There's often a lot of little things "nuzzled up" in
+/// a statement.
+fn write_extra<'tcx, F>(tcx: TyCtxt<'tcx>, write: &mut dyn Write, mut visit_op: F) -> io::Result<()>
+where
+ F: FnMut(&mut ExtraComments<'tcx>),
+{
+ let mut extra_comments = ExtraComments { tcx, comments: vec![] };
+ visit_op(&mut extra_comments);
+ for comment in extra_comments.comments {
+ writeln!(write, "{:A$} // {}", "", comment, A = ALIGN)?;
+ }
+ Ok(())
+}
+
+struct ExtraComments<'tcx> {
+ tcx: TyCtxt<'tcx>,
+ comments: Vec<String>,
+}
+
+impl<'tcx> ExtraComments<'tcx> {
+ fn push(&mut self, lines: &str) {
+ for line in lines.split('\n') {
+ self.comments.push(line.to_string());
+ }
+ }
+}
+
+fn use_verbose<'tcx>(ty: Ty<'tcx>, fn_def: bool) -> bool {
+ match *ty.kind() {
+ ty::Int(_) | ty::Uint(_) | ty::Bool | ty::Char | ty::Float(_) => false,
+ // Unit type
+ ty::Tuple(g_args) if g_args.is_empty() => false,
+ ty::Tuple(g_args) => g_args.iter().any(|g_arg| use_verbose(g_arg, fn_def)),
+ ty::Array(ty, _) => use_verbose(ty, fn_def),
+ ty::FnDef(..) => fn_def,
+ _ => true,
+ }
+}
+
+impl<'tcx> Visitor<'tcx> for ExtraComments<'tcx> {
+ fn visit_constant(&mut self, constant: &Constant<'tcx>, _location: Location) {
+ let Constant { span, user_ty, literal } = constant;
+ if use_verbose(literal.ty(), true) {
+ self.push("mir::Constant");
+ self.push(&format!(
+ "+ span: {}",
+ self.tcx.sess.source_map().span_to_embeddable_string(*span)
+ ));
+ if let Some(user_ty) = user_ty {
+ self.push(&format!("+ user_ty: {:?}", user_ty));
+ }
+
+ // FIXME: this is a poor version of `pretty_print_const_value`.
+ let fmt_val = |val: &ConstValue<'tcx>| match val {
+ ConstValue::ZeroSized => format!("<ZST>"),
+ ConstValue::Scalar(s) => format!("Scalar({:?})", s),
+ ConstValue::Slice { .. } => format!("Slice(..)"),
+ ConstValue::ByRef { .. } => format!("ByRef(..)"),
+ };
+
+ let fmt_valtree = |valtree: &ty::ValTree<'tcx>| match valtree {
+ ty::ValTree::Leaf(leaf) => format!("ValTree::Leaf({:?})", leaf),
+ ty::ValTree::Branch(_) => format!("ValTree::Branch(..)"),
+ };
+
+ let val = match literal {
+ ConstantKind::Ty(ct) => match ct.kind() {
+ ty::ConstKind::Param(p) => format!("Param({})", p),
+ ty::ConstKind::Unevaluated(uv) => format!(
+ "Unevaluated({}, {:?}, {:?})",
+ self.tcx.def_path_str(uv.def.did),
+ uv.substs,
+ uv.promoted,
+ ),
+ ty::ConstKind::Value(val) => format!("Value({})", fmt_valtree(&val)),
+ ty::ConstKind::Error(_) => "Error".to_string(),
+ // These variants shouldn't exist in the MIR.
+ ty::ConstKind::Placeholder(_)
+ | ty::ConstKind::Infer(_)
+ | ty::ConstKind::Bound(..) => bug!("unexpected MIR constant: {:?}", literal),
+ },
+ // To keep the diffs small, we render this like we render `ty::Const::Value`.
+ //
+ // This changes once `ty::Const::Value` is represented using valtrees.
+ ConstantKind::Val(val, _) => format!("Value({})", fmt_val(&val)),
+ };
+
+ // This reflects what `Const` looked liked before `val` was renamed
+ // as `kind`. We print it like this to avoid having to update
+ // expected output in a lot of tests.
+ self.push(&format!("+ literal: Const {{ ty: {}, val: {} }}", literal.ty(), val));
+ }
+ }
+
+ fn visit_rvalue(&mut self, rvalue: &Rvalue<'tcx>, location: Location) {
+ self.super_rvalue(rvalue, location);
+ if let Rvalue::Aggregate(kind, _) = rvalue {
+ match **kind {
+ AggregateKind::Closure(def_id, substs) => {
+ self.push("closure");
+ self.push(&format!("+ def_id: {:?}", def_id));
+ self.push(&format!("+ substs: {:#?}", substs));
+ }
+
+ AggregateKind::Generator(def_id, substs, movability) => {
+ self.push("generator");
+ self.push(&format!("+ def_id: {:?}", def_id));
+ self.push(&format!("+ substs: {:#?}", substs));
+ self.push(&format!("+ movability: {:?}", movability));
+ }
+
+ AggregateKind::Adt(_, _, _, Some(user_ty), _) => {
+ self.push("adt");
+ self.push(&format!("+ user_ty: {:?}", user_ty));
+ }
+
+ _ => {}
+ }
+ }
+ }
+}
+
+fn comment(tcx: TyCtxt<'_>, SourceInfo { span, scope }: SourceInfo, function_span: Span) -> String {
+ let location = if tcx.sess.opts.unstable_opts.mir_pretty_relative_line_numbers {
+ tcx.sess.source_map().span_to_relative_line_string(span, function_span)
+ } else {
+ tcx.sess.source_map().span_to_embeddable_string(span)
+ };
+
+ format!("scope {} at {}", scope.index(), location,)
+}
+
+/// Prints local variables in a scope tree.
+fn write_scope_tree(
+ tcx: TyCtxt<'_>,
+ body: &Body<'_>,
+ scope_tree: &FxHashMap<SourceScope, Vec<SourceScope>>,
+ w: &mut dyn Write,
+ parent: SourceScope,
+ depth: usize,
+) -> io::Result<()> {
+ let indent = depth * INDENT.len();
+
+ // Local variable debuginfo.
+ for var_debug_info in &body.var_debug_info {
+ if var_debug_info.source_info.scope != parent {
+ // Not declared in this scope.
+ continue;
+ }
+
+ let indented_debug_info = format!(
+ "{0:1$}debug {2} => {3:?};",
+ INDENT, indent, var_debug_info.name, var_debug_info.value,
+ );
+
+ writeln!(
+ w,
+ "{0:1$} // in {2}",
+ indented_debug_info,
+ ALIGN,
+ comment(tcx, var_debug_info.source_info, body.span),
+ )?;
+ }
+
+ // Local variable types.
+ for (local, local_decl) in body.local_decls.iter_enumerated() {
+ if (1..body.arg_count + 1).contains(&local.index()) {
+ // Skip over argument locals, they're printed in the signature.
+ continue;
+ }
+
+ if local_decl.source_info.scope != parent {
+ // Not declared in this scope.
+ continue;
+ }
+
+ let mut_str = if local_decl.mutability == Mutability::Mut { "mut " } else { "" };
+
+ let mut indented_decl =
+ format!("{0:1$}let {2}{3:?}: {4:?}", INDENT, indent, mut_str, local, local_decl.ty);
+ if let Some(user_ty) = &local_decl.user_ty {
+ for user_ty in user_ty.projections() {
+ write!(indented_decl, " as {:?}", user_ty).unwrap();
+ }
+ }
+ indented_decl.push(';');
+
+ let local_name = if local == RETURN_PLACE { " return place" } else { "" };
+
+ writeln!(
+ w,
+ "{0:1$} //{2} in {3}",
+ indented_decl,
+ ALIGN,
+ local_name,
+ comment(tcx, local_decl.source_info, body.span),
+ )?;
+ }
+
+ let Some(children) = scope_tree.get(&parent) else {
+ return Ok(());
+ };
+
+ for &child in children {
+ let child_data = &body.source_scopes[child];
+ assert_eq!(child_data.parent_scope, Some(parent));
+
+ let (special, span) = if let Some((callee, callsite_span)) = child_data.inlined {
+ (
+ format!(
+ " (inlined {}{})",
+ if callee.def.requires_caller_location(tcx) { "#[track_caller] " } else { "" },
+ callee
+ ),
+ Some(callsite_span),
+ )
+ } else {
+ (String::new(), None)
+ };
+
+ let indented_header = format!("{0:1$}scope {2}{3} {{", "", indent, child.index(), special);
+
+ if let Some(span) = span {
+ writeln!(
+ w,
+ "{0:1$} // at {2}",
+ indented_header,
+ ALIGN,
+ tcx.sess.source_map().span_to_embeddable_string(span),
+ )?;
+ } else {
+ writeln!(w, "{}", indented_header)?;
+ }
+
+ write_scope_tree(tcx, body, scope_tree, w, child, depth + 1)?;
+ writeln!(w, "{0:1$}}}", "", depth * INDENT.len())?;
+ }
+
+ Ok(())
+}
+
+/// Write out a human-readable textual representation of the MIR's `fn` type and the types of its
+/// local variables (both user-defined bindings and compiler temporaries).
+pub fn write_mir_intro<'tcx>(
+ tcx: TyCtxt<'tcx>,
+ body: &Body<'_>,
+ w: &mut dyn Write,
+) -> io::Result<()> {
+ write_mir_sig(tcx, body, w)?;
+ writeln!(w, "{{")?;
+
+ // construct a scope tree and write it out
+ let mut scope_tree: FxHashMap<SourceScope, Vec<SourceScope>> = Default::default();
+ for (index, scope_data) in body.source_scopes.iter().enumerate() {
+ if let Some(parent) = scope_data.parent_scope {
+ scope_tree.entry(parent).or_default().push(SourceScope::new(index));
+ } else {
+ // Only the argument scope has no parent, because it's the root.
+ assert_eq!(index, OUTERMOST_SOURCE_SCOPE.index());
+ }
+ }
+
+ write_scope_tree(tcx, body, &scope_tree, w, OUTERMOST_SOURCE_SCOPE, 1)?;
+
+ // Add an empty line before the first block is printed.
+ writeln!(w)?;
+
+ Ok(())
+}
+
+/// Find all `AllocId`s mentioned (recursively) in the MIR body and print their corresponding
+/// allocations.
+pub fn write_allocations<'tcx>(
+ tcx: TyCtxt<'tcx>,
+ body: &Body<'_>,
+ w: &mut dyn Write,
+) -> io::Result<()> {
+ fn alloc_ids_from_alloc(
+ alloc: ConstAllocation<'_>,
+ ) -> impl DoubleEndedIterator<Item = AllocId> + '_ {
+ alloc.inner().relocations().values().map(|id| *id)
+ }
+
+ fn alloc_ids_from_const_val(val: ConstValue<'_>) -> impl Iterator<Item = AllocId> + '_ {
+ match val {
+ ConstValue::Scalar(interpret::Scalar::Ptr(ptr, _)) => {
+ Either::Left(Either::Left(std::iter::once(ptr.provenance)))
+ }
+ ConstValue::Scalar(interpret::Scalar::Int { .. }) => {
+ Either::Left(Either::Right(std::iter::empty()))
+ }
+ ConstValue::ZeroSized => Either::Left(Either::Right(std::iter::empty())),
+ ConstValue::ByRef { alloc, .. } | ConstValue::Slice { data: alloc, .. } => {
+ Either::Right(alloc_ids_from_alloc(alloc))
+ }
+ }
+ }
+ struct CollectAllocIds(BTreeSet<AllocId>);
+
+ impl<'tcx> Visitor<'tcx> for CollectAllocIds {
+ fn visit_constant(&mut self, c: &Constant<'tcx>, loc: Location) {
+ match c.literal {
+ ConstantKind::Ty(c) => self.visit_const(c, loc),
+ ConstantKind::Val(val, _) => {
+ self.0.extend(alloc_ids_from_const_val(val));
+ }
+ }
+ }
+ }
+
+ let mut visitor = CollectAllocIds(Default::default());
+ visitor.visit_body(body);
+
+ // `seen` contains all seen allocations, including the ones we have *not* printed yet.
+ // The protocol is to first `insert` into `seen`, and only if that returns `true`
+ // then push to `todo`.
+ let mut seen = visitor.0;
+ let mut todo: Vec<_> = seen.iter().copied().collect();
+ while let Some(id) = todo.pop() {
+ let mut write_allocation_track_relocs =
+ |w: &mut dyn Write, alloc: ConstAllocation<'tcx>| -> io::Result<()> {
+ // `.rev()` because we are popping them from the back of the `todo` vector.
+ for id in alloc_ids_from_alloc(alloc).rev() {
+ if seen.insert(id) {
+ todo.push(id);
+ }
+ }
+ write!(w, "{}", display_allocation(tcx, alloc.inner()))
+ };
+ write!(w, "\n{id:?}")?;
+ match tcx.try_get_global_alloc(id) {
+ // This can't really happen unless there are bugs, but it doesn't cost us anything to
+ // gracefully handle it and allow buggy rustc to be debugged via allocation printing.
+ None => write!(w, " (deallocated)")?,
+ Some(GlobalAlloc::Function(inst)) => write!(w, " (fn: {inst})")?,
+ Some(GlobalAlloc::VTable(ty, Some(trait_ref))) => {
+ write!(w, " (vtable: impl {trait_ref} for {ty})")?
+ }
+ Some(GlobalAlloc::VTable(ty, None)) => {
+ write!(w, " (vtable: impl <auto trait> for {ty})")?
+ }
+ Some(GlobalAlloc::Static(did)) if !tcx.is_foreign_item(did) => {
+ match tcx.eval_static_initializer(did) {
+ Ok(alloc) => {
+ write!(w, " (static: {}, ", tcx.def_path_str(did))?;
+ write_allocation_track_relocs(w, alloc)?;
+ }
+ Err(_) => write!(
+ w,
+ " (static: {}, error during initializer evaluation)",
+ tcx.def_path_str(did)
+ )?,
+ }
+ }
+ Some(GlobalAlloc::Static(did)) => {
+ write!(w, " (extern static: {})", tcx.def_path_str(did))?
+ }
+ Some(GlobalAlloc::Memory(alloc)) => {
+ write!(w, " (")?;
+ write_allocation_track_relocs(w, alloc)?
+ }
+ }
+ writeln!(w)?;
+ }
+ Ok(())
+}
+
+/// Dumps the size and metadata and content of an allocation to the given writer.
+/// The expectation is that the caller first prints other relevant metadata, so the exact
+/// format of this function is (*without* leading or trailing newline):
+///
+/// ```text
+/// size: {}, align: {}) {
+/// <bytes>
+/// }
+/// ```
+///
+/// The byte format is similar to how hex editors print bytes. Each line starts with the address of
+/// the start of the line, followed by all bytes in hex format (space separated).
+/// If the allocation is small enough to fit into a single line, no start address is given.
+/// After the hex dump, an ascii dump follows, replacing all unprintable characters (control
+/// characters or characters whose value is larger than 127) with a `.`
+/// This also prints relocations adequately.
+pub fn display_allocation<'a, 'tcx, Prov, Extra>(
+ tcx: TyCtxt<'tcx>,
+ alloc: &'a Allocation<Prov, Extra>,
+) -> RenderAllocation<'a, 'tcx, Prov, Extra> {
+ RenderAllocation { tcx, alloc }
+}
+
+#[doc(hidden)]
+pub struct RenderAllocation<'a, 'tcx, Prov, Extra> {
+ tcx: TyCtxt<'tcx>,
+ alloc: &'a Allocation<Prov, Extra>,
+}
+
+impl<'a, 'tcx, Prov: Provenance, Extra> std::fmt::Display
+ for RenderAllocation<'a, 'tcx, Prov, Extra>
+{
+ fn fmt(&self, w: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+ let RenderAllocation { tcx, alloc } = *self;
+ write!(w, "size: {}, align: {})", alloc.size().bytes(), alloc.align.bytes())?;
+ if alloc.size() == Size::ZERO {
+ // We are done.
+ return write!(w, " {{}}");
+ }
+ // Write allocation bytes.
+ writeln!(w, " {{")?;
+ write_allocation_bytes(tcx, alloc, w, " ")?;
+ write!(w, "}}")?;
+ Ok(())
+ }
+}
+
+fn write_allocation_endline(w: &mut dyn std::fmt::Write, ascii: &str) -> std::fmt::Result {
+ for _ in 0..(BYTES_PER_LINE - ascii.chars().count()) {
+ write!(w, " ")?;
+ }
+ writeln!(w, " │ {}", ascii)
+}
+
+/// Number of bytes to print per allocation hex dump line.
+const BYTES_PER_LINE: usize = 16;
+
+/// Prints the line start address and returns the new line start address.
+fn write_allocation_newline(
+ w: &mut dyn std::fmt::Write,
+ mut line_start: Size,
+ ascii: &str,
+ pos_width: usize,
+ prefix: &str,
+) -> Result<Size, std::fmt::Error> {
+ write_allocation_endline(w, ascii)?;
+ line_start += Size::from_bytes(BYTES_PER_LINE);
+ write!(w, "{}0x{:02$x} │ ", prefix, line_start.bytes(), pos_width)?;
+ Ok(line_start)
+}
+
+/// The `prefix` argument allows callers to add an arbitrary prefix before each line (even if there
+/// is only one line). Note that your prefix should contain a trailing space as the lines are
+/// printed directly after it.
+fn write_allocation_bytes<'tcx, Prov: Provenance, Extra>(
+ tcx: TyCtxt<'tcx>,
+ alloc: &Allocation<Prov, Extra>,
+ w: &mut dyn std::fmt::Write,
+ prefix: &str,
+) -> std::fmt::Result {
+ let num_lines = alloc.size().bytes_usize().saturating_sub(BYTES_PER_LINE);
+ // Number of chars needed to represent all line numbers.
+ let pos_width = hex_number_length(alloc.size().bytes());
+
+ if num_lines > 0 {
+ write!(w, "{}0x{:02$x} │ ", prefix, 0, pos_width)?;
+ } else {
+ write!(w, "{}", prefix)?;
+ }
+
+ let mut i = Size::ZERO;
+ let mut line_start = Size::ZERO;
+
+ let ptr_size = tcx.data_layout.pointer_size;
+
+ let mut ascii = String::new();
+
+ let oversized_ptr = |target: &mut String, width| {
+ if target.len() > width {
+ write!(target, " ({} ptr bytes)", ptr_size.bytes()).unwrap();
+ }
+ };
+
+ while i < alloc.size() {
+ // The line start already has a space. While we could remove that space from the line start
+ // printing and unconditionally print a space here, that would cause the single-line case
+ // to have a single space before it, which looks weird.
+ if i != line_start {
+ write!(w, " ")?;
+ }
+ if let Some(&prov) = alloc.relocations().get(&i) {
+ // Memory with a relocation must be defined
+ assert!(alloc.init_mask().is_range_initialized(i, i + ptr_size).is_ok());
+ let j = i.bytes_usize();
+ let offset = alloc
+ .inspect_with_uninit_and_ptr_outside_interpreter(j..j + ptr_size.bytes_usize());
+ let offset = read_target_uint(tcx.data_layout.endian, offset).unwrap();
+ let offset = Size::from_bytes(offset);
+ let relocation_width = |bytes| bytes * 3;
+ let ptr = Pointer::new(prov, offset);
+ let mut target = format!("{:?}", ptr);
+ if target.len() > relocation_width(ptr_size.bytes_usize() - 1) {
+ // This is too long, try to save some space.
+ target = format!("{:#?}", ptr);
+ }
+ if ((i - line_start) + ptr_size).bytes_usize() > BYTES_PER_LINE {
+ // This branch handles the situation where a relocation starts in the current line
+ // but ends in the next one.
+ let remainder = Size::from_bytes(BYTES_PER_LINE) - (i - line_start);
+ let overflow = ptr_size - remainder;
+ let remainder_width = relocation_width(remainder.bytes_usize()) - 2;
+ let overflow_width = relocation_width(overflow.bytes_usize() - 1) + 1;
+ ascii.push('╾');
+ for _ in 0..remainder.bytes() - 1 {
+ ascii.push('─');
+ }
+ if overflow_width > remainder_width && overflow_width >= target.len() {
+ // The case where the relocation fits into the part in the next line
+ write!(w, "╾{0:─^1$}", "", remainder_width)?;
+ line_start =
+ write_allocation_newline(w, line_start, &ascii, pos_width, prefix)?;
+ ascii.clear();
+ write!(w, "{0:─^1$}╼", target, overflow_width)?;
+ } else {
+ oversized_ptr(&mut target, remainder_width);
+ write!(w, "╾{0:─^1$}", target, remainder_width)?;
+ line_start =
+ write_allocation_newline(w, line_start, &ascii, pos_width, prefix)?;
+ write!(w, "{0:─^1$}╼", "", overflow_width)?;
+ ascii.clear();
+ }
+ for _ in 0..overflow.bytes() - 1 {
+ ascii.push('─');
+ }
+ ascii.push('╼');
+ i += ptr_size;
+ continue;
+ } else {
+ // This branch handles a relocation that starts and ends in the current line.
+ let relocation_width = relocation_width(ptr_size.bytes_usize() - 1);
+ oversized_ptr(&mut target, relocation_width);
+ ascii.push('╾');
+ write!(w, "╾{0:─^1$}╼", target, relocation_width)?;
+ for _ in 0..ptr_size.bytes() - 2 {
+ ascii.push('─');
+ }
+ ascii.push('╼');
+ i += ptr_size;
+ }
+ } else if alloc.init_mask().is_range_initialized(i, i + Size::from_bytes(1)).is_ok() {
+ let j = i.bytes_usize();
+
+ // Checked definedness (and thus range) and relocations. This access also doesn't
+ // influence interpreter execution but is only for debugging.
+ let c = alloc.inspect_with_uninit_and_ptr_outside_interpreter(j..j + 1)[0];
+ write!(w, "{:02x}", c)?;
+ if c.is_ascii_control() || c >= 0x80 {
+ ascii.push('.');
+ } else {
+ ascii.push(char::from(c));
+ }
+ i += Size::from_bytes(1);
+ } else {
+ write!(w, "__")?;
+ ascii.push('░');
+ i += Size::from_bytes(1);
+ }
+ // Print a new line header if the next line still has some bytes to print.
+ if i == line_start + Size::from_bytes(BYTES_PER_LINE) && i != alloc.size() {
+ line_start = write_allocation_newline(w, line_start, &ascii, pos_width, prefix)?;
+ ascii.clear();
+ }
+ }
+ write_allocation_endline(w, &ascii)?;
+
+ Ok(())
+}
+
+fn write_mir_sig(tcx: TyCtxt<'_>, body: &Body<'_>, w: &mut dyn Write) -> io::Result<()> {
+ use rustc_hir::def::DefKind;
+
+ trace!("write_mir_sig: {:?}", body.source.instance);
+ let def_id = body.source.def_id();
+ let kind = tcx.def_kind(def_id);
+ let is_function = match kind {
+ DefKind::Fn | DefKind::AssocFn | DefKind::Ctor(..) => true,
+ _ => tcx.is_closure(def_id),
+ };
+ match (kind, body.source.promoted) {
+ (_, Some(i)) => write!(w, "{:?} in ", i)?,
+ (DefKind::Const | DefKind::AssocConst, _) => write!(w, "const ")?,
+ (DefKind::Static(hir::Mutability::Not), _) => write!(w, "static ")?,
+ (DefKind::Static(hir::Mutability::Mut), _) => write!(w, "static mut ")?,
+ (_, _) if is_function => write!(w, "fn ")?,
+ (DefKind::AnonConst | DefKind::InlineConst, _) => {} // things like anon const, not an item
+ _ => bug!("Unexpected def kind {:?}", kind),
+ }
+
+ ty::print::with_forced_impl_filename_line! {
+ // see notes on #41697 elsewhere
+ write!(w, "{}", tcx.def_path_str(def_id))?
+ }
+
+ if body.source.promoted.is_none() && is_function {
+ write!(w, "(")?;
+
+ // fn argument types.
+ for (i, arg) in body.args_iter().enumerate() {
+ if i != 0 {
+ write!(w, ", ")?;
+ }
+ write!(w, "{:?}: {}", Place::from(arg), body.local_decls[arg].ty)?;
+ }
+
+ write!(w, ") -> {}", body.return_ty())?;
+ } else {
+ assert_eq!(body.arg_count, 0);
+ write!(w, ": {} =", body.return_ty())?;
+ }
+
+ if let Some(yield_ty) = body.yield_ty() {
+ writeln!(w)?;
+ writeln!(w, "yields {}", yield_ty)?;
+ }
+
+ write!(w, " ")?;
+ // Next thing that gets printed is the opening {
+
+ Ok(())
+}
+
+fn write_user_type_annotations(
+ tcx: TyCtxt<'_>,
+ body: &Body<'_>,
+ w: &mut dyn Write,
+) -> io::Result<()> {
+ if !body.user_type_annotations.is_empty() {
+ writeln!(w, "| User Type Annotations")?;
+ }
+ for (index, annotation) in body.user_type_annotations.iter_enumerated() {
+ writeln!(
+ w,
+ "| {:?}: user_ty: {:?}, span: {}, inferred_ty: {:?}",
+ index.index(),
+ annotation.user_ty,
+ tcx.sess.source_map().span_to_embeddable_string(annotation.span),
+ annotation.inferred_ty,
+ )?;
+ }
+ if !body.user_type_annotations.is_empty() {
+ writeln!(w, "|")?;
+ }
+ Ok(())
+}
+
+pub fn dump_mir_def_ids(tcx: TyCtxt<'_>, single: Option<DefId>) -> Vec<DefId> {
+ if let Some(i) = single {
+ vec![i]
+ } else {
+ tcx.mir_keys(()).iter().map(|def_id| def_id.to_def_id()).collect()
+ }
+}
+
+/// Calc converted u64 decimal into hex and return it's length in chars
+///
+/// ```ignore (cannot-test-private-function)
+/// assert_eq!(1, hex_number_length(0));
+/// assert_eq!(1, hex_number_length(1));
+/// assert_eq!(2, hex_number_length(16));
+/// ```
+fn hex_number_length(x: u64) -> usize {
+ if x == 0 {
+ return 1;
+ }
+ let mut length = 0;
+ let mut x_left = x;
+ while x_left > 0 {
+ x_left /= 16;
+ length += 1;
+ }
+ length
+}