diff options
Diffstat (limited to 'compiler/rustc_codegen_llvm/src/debuginfo/create_scope_map.rs')
-rw-r--r-- | compiler/rustc_codegen_llvm/src/debuginfo/create_scope_map.rs | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/create_scope_map.rs b/compiler/rustc_codegen_llvm/src/debuginfo/create_scope_map.rs new file mode 100644 index 000000000..99e4ded62 --- /dev/null +++ b/compiler/rustc_codegen_llvm/src/debuginfo/create_scope_map.rs @@ -0,0 +1,126 @@ +use super::metadata::file_metadata; +use super::utils::DIB; +use rustc_codegen_ssa::mir::debuginfo::{DebugScope, FunctionDebugContext}; +use rustc_codegen_ssa::traits::*; + +use crate::common::CodegenCx; +use crate::llvm; +use crate::llvm::debuginfo::{DILocation, DIScope}; +use rustc_middle::mir::{Body, SourceScope}; +use rustc_middle::ty::layout::FnAbiOf; +use rustc_middle::ty::{self, Instance}; +use rustc_session::config::DebugInfo; + +use rustc_index::bit_set::BitSet; +use rustc_index::vec::Idx; + +/// Produces DIScope DIEs for each MIR Scope which has variables defined in it. +// FIXME(eddyb) almost all of this should be in `rustc_codegen_ssa::mir::debuginfo`. +pub fn compute_mir_scopes<'ll, 'tcx>( + cx: &CodegenCx<'ll, 'tcx>, + instance: Instance<'tcx>, + mir: &Body<'tcx>, + debug_context: &mut FunctionDebugContext<&'ll DIScope, &'ll DILocation>, +) { + // Find all scopes with variables defined in them. + let variables = if cx.sess().opts.debuginfo == DebugInfo::Full { + let mut vars = BitSet::new_empty(mir.source_scopes.len()); + // FIXME(eddyb) take into account that arguments always have debuginfo, + // irrespective of their name (assuming full debuginfo is enabled). + // NOTE(eddyb) actually, on second thought, those are always in the + // function scope, which always exists. + for var_debug_info in &mir.var_debug_info { + vars.insert(var_debug_info.source_info.scope); + } + Some(vars) + } else { + // Nothing to emit, of course. + None + }; + let mut instantiated = BitSet::new_empty(mir.source_scopes.len()); + // Instantiate all scopes. + for idx in 0..mir.source_scopes.len() { + let scope = SourceScope::new(idx); + make_mir_scope(cx, instance, mir, &variables, debug_context, &mut instantiated, scope); + } + assert!(instantiated.count() == mir.source_scopes.len()); +} + +fn make_mir_scope<'ll, 'tcx>( + cx: &CodegenCx<'ll, 'tcx>, + instance: Instance<'tcx>, + mir: &Body<'tcx>, + variables: &Option<BitSet<SourceScope>>, + debug_context: &mut FunctionDebugContext<&'ll DIScope, &'ll DILocation>, + instantiated: &mut BitSet<SourceScope>, + scope: SourceScope, +) { + if instantiated.contains(scope) { + return; + } + + let scope_data = &mir.source_scopes[scope]; + let parent_scope = if let Some(parent) = scope_data.parent_scope { + make_mir_scope(cx, instance, mir, variables, debug_context, instantiated, parent); + debug_context.scopes[parent] + } else { + // The root is the function itself. + let loc = cx.lookup_debug_loc(mir.span.lo()); + debug_context.scopes[scope] = DebugScope { + file_start_pos: loc.file.start_pos, + file_end_pos: loc.file.end_pos, + ..debug_context.scopes[scope] + }; + instantiated.insert(scope); + return; + }; + + if let Some(vars) = variables && !vars.contains(scope) && scope_data.inlined.is_none() { + // Do not create a DIScope if there are no variables defined in this + // MIR `SourceScope`, and it's not `inlined`, to avoid debuginfo bloat. + debug_context.scopes[scope] = parent_scope; + instantiated.insert(scope); + return; + } + + let loc = cx.lookup_debug_loc(scope_data.span.lo()); + let file_metadata = file_metadata(cx, &loc.file); + + let dbg_scope = match scope_data.inlined { + Some((callee, _)) => { + // FIXME(eddyb) this would be `self.monomorphize(&callee)` + // if this is moved to `rustc_codegen_ssa::mir::debuginfo`. + let callee = cx.tcx.subst_and_normalize_erasing_regions( + instance.substs, + ty::ParamEnv::reveal_all(), + callee, + ); + let callee_fn_abi = cx.fn_abi_of_instance(callee, ty::List::empty()); + cx.dbg_scope_fn(callee, callee_fn_abi, None) + } + None => unsafe { + llvm::LLVMRustDIBuilderCreateLexicalBlock( + DIB(cx), + parent_scope.dbg_scope, + file_metadata, + loc.line, + loc.col, + ) + }, + }; + + let inlined_at = scope_data.inlined.map(|(_, callsite_span)| { + // FIXME(eddyb) this doesn't account for the macro-related + // `Span` fixups that `rustc_codegen_ssa::mir::debuginfo` does. + let callsite_scope = parent_scope.adjust_dbg_scope_for_span(cx, callsite_span); + cx.dbg_loc(callsite_scope, parent_scope.inlined_at, callsite_span) + }); + + debug_context.scopes[scope] = DebugScope { + dbg_scope, + inlined_at: inlined_at.or(parent_scope.inlined_at), + file_start_pos: loc.file.start_pos, + file_end_pos: loc.file.end_pos, + }; + instantiated.insert(scope); +} |