1 // Copyright 2012-2015 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.
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.
11 // See doc.rs for documentation.
14 use self::VariableAccess::*;
15 use self::VariableKind::*;
17 use self::utils::{DIB, span_start, create_DIArray, is_node_local_to_unit};
18 use self::namespace::mangled_name_of_item;
19 use self::type_names::compute_debuginfo_type_name;
20 use self::metadata::{type_metadata, file_metadata, TypeMap};
21 use self::source_loc::InternalDebugLocation::{self, UnknownLocation};
24 use llvm::{ModuleRef, ContextRef, ValueRef};
25 use llvm::debuginfo::{DIFile, DIType, DIScope, DIBuilderRef, DISubprogram, DIArray, DIFlags};
26 use rustc::hir::def_id::{DefId, CrateNum};
27 use rustc::ty::subst::Substs;
30 use common::{self, CrateContext};
32 use monomorphize::Instance;
33 use rustc::ty::{self, Ty};
35 use session::config::{self, FullDebugInfo, LimitedDebugInfo, NoDebugInfo};
36 use util::nodemap::{DefIdMap, FxHashMap, FxHashSet};
39 use std::cell::{Cell, RefCell};
40 use std::ffi::CString;
43 use syntax_pos::{self, Span, Pos};
45 use syntax::symbol::Symbol;
46 use rustc::ty::layout;
56 pub use self::create_scope_map::{create_mir_scopes, MirDebugScope};
57 pub use self::source_loc::start_emitting_source_locations;
58 pub use self::metadata::create_global_var_metadata;
59 pub use self::metadata::extend_scope_to_file;
60 pub use self::source_loc::set_source_location;
62 #[allow(non_upper_case_globals)]
63 const DW_TAG_auto_variable: c_uint = 0x100;
64 #[allow(non_upper_case_globals)]
65 const DW_TAG_arg_variable: c_uint = 0x101;
67 /// A context object for maintaining all state needed by the debuginfo module.
68 pub struct CrateDebugContext<'tcx> {
69 llcontext: ContextRef,
70 builder: DIBuilderRef,
71 created_files: RefCell<FxHashMap<(Symbol, Symbol), DIFile>>,
72 created_enum_disr_types: RefCell<FxHashMap<(DefId, layout::Integer), DIType>>,
74 type_map: RefCell<TypeMap<'tcx>>,
75 namespace_map: RefCell<DefIdMap<DIScope>>,
77 // This collection is used to assert that composite types (structs, enums,
78 // ...) have their members only set once:
79 composite_types_completed: RefCell<FxHashSet<DIType>>,
82 impl<'tcx> CrateDebugContext<'tcx> {
83 pub fn new(llmod: ModuleRef) -> CrateDebugContext<'tcx> {
84 debug!("CrateDebugContext::new");
85 let builder = unsafe { llvm::LLVMRustDIBuilderCreate(llmod) };
86 // DIBuilder inherits context from the module, so we'd better use the same one
87 let llcontext = unsafe { llvm::LLVMGetModuleContext(llmod) };
91 created_files: RefCell::new(FxHashMap()),
92 created_enum_disr_types: RefCell::new(FxHashMap()),
93 type_map: RefCell::new(TypeMap::new()),
94 namespace_map: RefCell::new(DefIdMap()),
95 composite_types_completed: RefCell::new(FxHashSet()),
100 pub enum FunctionDebugContext {
101 RegularContext(FunctionDebugContextData),
103 FunctionWithoutDebugInfo,
106 impl FunctionDebugContext {
107 pub fn get_ref<'a>(&'a self, span: Span) -> &'a FunctionDebugContextData {
109 FunctionDebugContext::RegularContext(ref data) => data,
110 FunctionDebugContext::DebugInfoDisabled => {
111 span_bug!(span, "{}", FunctionDebugContext::debuginfo_disabled_message());
113 FunctionDebugContext::FunctionWithoutDebugInfo => {
114 span_bug!(span, "{}", FunctionDebugContext::should_be_ignored_message());
119 fn debuginfo_disabled_message() -> &'static str {
120 "debuginfo: Error trying to access FunctionDebugContext although debug info is disabled!"
123 fn should_be_ignored_message() -> &'static str {
124 "debuginfo: Error trying to access FunctionDebugContext for function that should be \
125 ignored by debug info!"
129 pub struct FunctionDebugContextData {
130 fn_metadata: DISubprogram,
131 source_locations_enabled: Cell<bool>,
132 pub defining_crate: CrateNum,
135 pub enum VariableAccess<'a> {
136 // The llptr given is an alloca containing the variable's value
137 DirectVariable { alloca: ValueRef },
138 // The llptr given is an alloca containing the start of some pointer chain
139 // leading to the variable's content.
140 IndirectVariable { alloca: ValueRef, address_operations: &'a [i64] }
143 pub enum VariableKind {
144 ArgumentVariable(usize /*index*/),
149 /// Create any deferred debug metadata nodes
150 pub fn finalize(cx: &CrateContext) {
151 if cx.dbg_cx().is_none() {
157 if gdb::needs_gdb_debug_scripts_section(cx) {
158 // Add a .debug_gdb_scripts section to this compile-unit. This will
159 // cause GDB to try and load the gdb_load_rust_pretty_printers.py file,
160 // which activates the Rust pretty printers for binary this section is
162 gdb::get_or_insert_gdb_debug_scripts_section_global(cx);
166 llvm::LLVMRustDIBuilderFinalize(DIB(cx));
167 llvm::LLVMRustDIBuilderDispose(DIB(cx));
168 // Debuginfo generation in LLVM by default uses a higher
169 // version of dwarf than macOS currently understands. We can
170 // instruct LLVM to emit an older version of dwarf, however,
171 // for macOS to understand. For more info see #11352
172 // This can be overridden using --llvm-opts -dwarf-version,N.
173 // Android has the same issue (#22398)
174 if cx.sess().target.target.options.is_like_osx ||
175 cx.sess().target.target.options.is_like_android {
176 llvm::LLVMRustAddModuleFlag(cx.llmod(),
177 "Dwarf Version\0".as_ptr() as *const _,
181 // Indicate that we want CodeView debug information on MSVC
182 if cx.sess().target.target.options.is_like_msvc {
183 llvm::LLVMRustAddModuleFlag(cx.llmod(),
184 "CodeView\0".as_ptr() as *const _,
188 // Prevent bitcode readers from deleting the debug info.
189 let ptr = "Debug Info Version\0".as_ptr();
190 llvm::LLVMRustAddModuleFlag(cx.llmod(), ptr as *const _,
191 llvm::LLVMRustDebugMetadataVersion());
195 /// Creates the function-specific debug context.
197 /// Returns the FunctionDebugContext for the function which holds state needed
198 /// for debug info creation. The function may also return another variant of the
199 /// FunctionDebugContext enum which indicates why no debuginfo should be created
200 /// for the function.
201 pub fn create_function_debug_context<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
202 instance: Instance<'tcx>,
203 sig: ty::FnSig<'tcx>,
205 mir: &mir::Mir) -> FunctionDebugContext {
206 if cx.sess().opts.debuginfo == NoDebugInfo {
207 return FunctionDebugContext::DebugInfoDisabled;
210 for attr in instance.def.attrs(cx.tcx()).iter() {
211 if attr.check_name("no_debug") {
212 return FunctionDebugContext::FunctionWithoutDebugInfo;
216 let containing_scope = get_containing_scope(cx, instance);
219 // This can be the case for functions inlined from another crate
220 if span == syntax_pos::DUMMY_SP {
221 // FIXME(simulacrum): Probably can't happen; remove.
222 return FunctionDebugContext::FunctionWithoutDebugInfo;
225 let def_id = instance.def_id();
226 let loc = span_start(cx, span);
227 let file_metadata = file_metadata(cx, &loc.file.name, def_id.krate);
229 let function_type_metadata = unsafe {
230 let fn_signature = get_function_signature(cx, sig);
231 llvm::LLVMRustDIBuilderCreateSubroutineType(DIB(cx), file_metadata, fn_signature)
234 // Find the enclosing function, in case this is a closure.
235 let def_key = cx.tcx().def_key(def_id);
236 let mut name = def_key.disambiguated_data.data.to_string();
237 let name_len = name.len();
239 let enclosing_fn_def_id = cx.tcx().closure_base_def_id(def_id);
241 // Get_template_parameters() will append a `<...>` clause to the function
242 // name if necessary.
243 let generics = cx.tcx().generics_of(enclosing_fn_def_id);
244 let substs = instance.substs.truncate_to(cx.tcx(), generics);
245 let template_parameters = get_template_parameters(cx,
251 // Build the linkage_name out of the item path and "template" parameters.
252 let linkage_name = mangled_name_of_item(cx, instance.def_id(), &name[name_len..]);
254 let scope_line = span_start(cx, span).line;
256 let local_id = cx.tcx().hir.as_local_node_id(instance.def_id());
257 let is_local_to_unit = local_id.map_or(false, |id| is_node_local_to_unit(cx, id));
259 let function_name = CString::new(name).unwrap();
260 let linkage_name = CString::new(linkage_name).unwrap();
262 let mut flags = DIFlags::FlagPrototyped;
263 match *cx.sess().entry_fn.borrow() {
265 if local_id == Some(id) {
266 flags = flags | DIFlags::FlagMainSubprogram;
272 let fn_metadata = unsafe {
273 llvm::LLVMRustDIBuilderCreateFunction(
276 function_name.as_ptr(),
277 linkage_name.as_ptr(),
280 function_type_metadata,
283 scope_line as c_uint,
285 cx.sess().opts.optimize != config::OptLevel::No,
291 // Initialize fn debug context (including scope map and namespace map)
292 let fn_debug_context = FunctionDebugContextData {
293 fn_metadata: fn_metadata,
294 source_locations_enabled: Cell::new(false),
295 defining_crate: def_id.krate,
298 return FunctionDebugContext::RegularContext(fn_debug_context);
300 fn get_function_signature<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
301 sig: ty::FnSig<'tcx>) -> DIArray {
302 if cx.sess().opts.debuginfo == LimitedDebugInfo {
303 return create_DIArray(DIB(cx), &[]);
306 let mut signature = Vec::with_capacity(sig.inputs().len() + 1);
308 // Return type -- llvm::DIBuilder wants this at index 0
309 signature.push(match sig.output().sty {
310 ty::TyTuple(ref tys, _) if tys.is_empty() => ptr::null_mut(),
311 _ => type_metadata(cx, sig.output(), syntax_pos::DUMMY_SP)
314 let inputs = if sig.abi == Abi::RustCall {
315 &sig.inputs()[..sig.inputs().len() - 1]
321 for &argument_type in inputs {
322 signature.push(type_metadata(cx, argument_type, syntax_pos::DUMMY_SP));
325 if sig.abi == Abi::RustCall && !sig.inputs().is_empty() {
326 if let ty::TyTuple(args, _) = sig.inputs()[sig.inputs().len() - 1].sty {
327 for &argument_type in args {
328 signature.push(type_metadata(cx, argument_type, syntax_pos::DUMMY_SP));
333 return create_DIArray(DIB(cx), &signature[..]);
336 fn get_template_parameters<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
337 generics: &ty::Generics,
338 substs: &Substs<'tcx>,
339 file_metadata: DIFile,
340 name_to_append_suffix_to: &mut String)
343 if substs.types().next().is_none() {
344 return create_DIArray(DIB(cx), &[]);
347 name_to_append_suffix_to.push('<');
348 for (i, actual_type) in substs.types().enumerate() {
350 name_to_append_suffix_to.push_str(",");
353 let actual_type = cx.tcx().normalize_associated_type(&actual_type);
354 // Add actual type name to <...> clause of function name
355 let actual_type_name = compute_debuginfo_type_name(cx,
358 name_to_append_suffix_to.push_str(&actual_type_name[..]);
360 name_to_append_suffix_to.push('>');
362 // Again, only create type information if full debuginfo is enabled
363 let template_params: Vec<_> = if cx.sess().opts.debuginfo == FullDebugInfo {
364 let names = get_type_parameter_names(cx, generics);
365 substs.types().zip(names).map(|(ty, name)| {
366 let actual_type = cx.tcx().normalize_associated_type(&ty);
367 let actual_type_metadata = type_metadata(cx, actual_type, syntax_pos::DUMMY_SP);
368 let name = CString::new(name.as_str().as_bytes()).unwrap();
370 llvm::LLVMRustDIBuilderCreateTemplateTypeParameter(
374 actual_type_metadata,
384 return create_DIArray(DIB(cx), &template_params[..]);
387 fn get_type_parameter_names(cx: &CrateContext, generics: &ty::Generics) -> Vec<ast::Name> {
388 let mut names = generics.parent.map_or(vec![], |def_id| {
389 get_type_parameter_names(cx, cx.tcx().generics_of(def_id))
391 names.extend(generics.types.iter().map(|param| param.name));
395 fn get_containing_scope<'ccx, 'tcx>(cx: &CrateContext<'ccx, 'tcx>,
396 instance: Instance<'tcx>)
398 // First, let's see if this is a method within an inherent impl. Because
399 // if yes, we want to make the result subroutine DIE a child of the
400 // subroutine's self-type.
401 let self_type = cx.tcx().impl_of_method(instance.def_id()).and_then(|impl_def_id| {
402 // If the method does *not* belong to a trait, proceed
403 if cx.tcx().trait_id_of_impl(impl_def_id).is_none() {
405 common::def_ty(cx.shared(), impl_def_id, instance.substs);
407 // Only "class" methods are generally understood by LLVM,
408 // so avoid methods on other types (e.g. `<*mut T>::null`).
409 match impl_self_ty.sty {
410 ty::TyAdt(def, ..) if !def.is_box() => {
411 Some(type_metadata(cx, impl_self_ty, syntax_pos::DUMMY_SP))
416 // For trait method impls we still use the "parallel namespace"
422 self_type.unwrap_or_else(|| {
423 namespace::item_namespace(cx, DefId {
424 krate: instance.def_id().krate,
426 .def_key(instance.def_id())
428 .expect("get_containing_scope: missing parent?")
434 pub fn declare_local<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
435 dbg_context: &FunctionDebugContext,
436 variable_name: ast::Name,
437 variable_type: Ty<'tcx>,
438 scope_metadata: DIScope,
439 variable_access: VariableAccess,
440 variable_kind: VariableKind,
444 let file = span_start(cx, span).file;
445 let file_metadata = file_metadata(cx,
447 dbg_context.get_ref(span).defining_crate);
449 let loc = span_start(cx, span);
450 let type_metadata = type_metadata(cx, variable_type, span);
452 let (argument_index, dwarf_tag) = match variable_kind {
453 ArgumentVariable(index) => (index as c_uint, DW_TAG_arg_variable),
455 CapturedVariable => (0, DW_TAG_auto_variable)
457 let align = cx.align_of(variable_type);
459 let name = CString::new(variable_name.as_str().as_bytes()).unwrap();
460 match (variable_access, &[][..]) {
461 (DirectVariable { alloca }, address_operations) |
462 (IndirectVariable {alloca, address_operations}, _) => {
463 let metadata = unsafe {
464 llvm::LLVMRustDIBuilderCreateVariable(
472 cx.sess().opts.optimize != config::OptLevel::No,
478 source_loc::set_debug_location(bcx,
479 InternalDebugLocation::new(scope_metadata, loc.line, loc.col.to_usize()));
481 let debug_loc = llvm::LLVMGetCurrentDebugLocation(bcx.llbuilder);
482 let instr = llvm::LLVMRustDIBuilderInsertDeclareAtEnd(
486 address_operations.as_ptr(),
487 address_operations.len() as c_uint,
491 llvm::LLVMSetInstDebugLocation(bcx.llbuilder, instr);
496 match variable_kind {
497 ArgumentVariable(_) | CapturedVariable => {
498 assert!(!dbg_context.get_ref(span).source_locations_enabled.get());
499 source_loc::set_debug_location(bcx, UnknownLocation);
501 _ => { /* nothing to do */ }