diff options
Diffstat (limited to 'compiler')
4 files changed, 53 insertions, 31 deletions
diff --git a/compiler/rustc_codegen_gcc/src/debuginfo.rs b/compiler/rustc_codegen_gcc/src/debuginfo.rs index 5d8c5c199b1..6aeb656c1ab 100644 --- a/compiler/rustc_codegen_gcc/src/debuginfo.rs +++ b/compiler/rustc_codegen_gcc/src/debuginfo.rs @@ -113,15 +113,15 @@ fn make_mir_scope<'gcc, 'tcx>( 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] + debug_context.scopes[parent].unwrap() } else { // The root is the function itself. let file = cx.sess().source_map().lookup_source_file(mir.span.lo()); - debug_context.scopes[scope] = DebugScope { + debug_context.scopes[scope] = Some(DebugScope { file_start_pos: file.start_pos, file_end_pos: file.end_position(), - ..debug_context.scopes[scope] - }; + ..debug_context.scopes[scope].unwrap() + }); instantiated.insert(scope); return; }; @@ -130,7 +130,7 @@ fn make_mir_scope<'gcc, 'tcx>( if !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; + debug_context.scopes[scope] = Some(parent_scope); instantiated.insert(scope); return; } @@ -157,12 +157,12 @@ fn make_mir_scope<'gcc, 'tcx>( // TODO(tempdragon): dbg_scope: Add support for scope extension here. inlined_at.or(p_inlined_at); - debug_context.scopes[scope] = DebugScope { + debug_context.scopes[scope] = Some(DebugScope { dbg_scope, inlined_at, file_start_pos: loc.file.start_pos, file_end_pos: loc.file.end_position(), - }; + }); instantiated.insert(scope); } @@ -232,12 +232,12 @@ impl<'gcc, 'tcx> DebugInfoCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> { } // Initialize fn debug context (including scopes). - let empty_scope = DebugScope { + let empty_scope = Some(DebugScope { dbg_scope: self.dbg_scope_fn(instance, fn_abi, Some(llfn)), inlined_at: None, file_start_pos: BytePos(0), file_end_pos: BytePos(0), - }; + }); let mut fn_debug_context = FunctionDebugContext { scopes: IndexVec::from_elem(empty_scope, mir.source_scopes.as_slice()), inlined_function_scopes: Default::default(), diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/create_scope_map.rs b/compiler/rustc_codegen_llvm/src/debuginfo/create_scope_map.rs index 2c7ef626d1e..07bd0f4d1c1 100644 --- a/compiler/rustc_codegen_llvm/src/debuginfo/create_scope_map.rs +++ b/compiler/rustc_codegen_llvm/src/debuginfo/create_scope_map.rs @@ -85,15 +85,23 @@ fn make_mir_scope<'ll, 'tcx>( discriminators, parent, ); - debug_context.scopes[parent] + if let Some(parent_scope) = debug_context.scopes[parent] { + parent_scope + } else { + // If the parent scope could not be represented then no children + // can be either. + debug_context.scopes[scope] = None; + instantiated.insert(scope); + return; + } } else { // The root is the function itself. let file = cx.sess().source_map().lookup_source_file(mir.span.lo()); - debug_context.scopes[scope] = DebugScope { + debug_context.scopes[scope] = Some(DebugScope { file_start_pos: file.start_pos, file_end_pos: file.end_position(), - ..debug_context.scopes[scope] - }; + ..debug_context.scopes[scope].unwrap() + }); instantiated.insert(scope); return; }; @@ -104,7 +112,7 @@ fn make_mir_scope<'ll, 'tcx>( { // 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; + debug_context.scopes[scope] = Some(parent_scope); instantiated.insert(scope); return; } @@ -137,13 +145,20 @@ fn make_mir_scope<'ll, 'tcx>( }, }; - let inlined_at = scope_data.inlined.map(|(_, callsite_span)| { + let mut debug_scope = Some(DebugScope { + dbg_scope, + inlined_at: parent_scope.inlined_at, + file_start_pos: loc.file.start_pos, + file_end_pos: loc.file.end_position(), + }); + + if let Some((_, callsite_span)) = scope_data.inlined { let callsite_span = hygiene::walk_chain_collapsed(callsite_span, mir.span); let callsite_scope = parent_scope.adjust_dbg_scope_for_span(cx, callsite_span); let loc = cx.dbg_loc(callsite_scope, parent_scope.inlined_at, callsite_span); // NB: In order to produce proper debug info for variables (particularly - // arguments) in multiply-inline functions, LLVM expects to see a single + // arguments) in multiply-inlined functions, LLVM expects to see a single // DILocalVariable with multiple different DILocations in the IR. While // the source information for each DILocation would be identical, their // inlinedAt attributes will be unique to the particular callsite. @@ -151,7 +166,7 @@ fn make_mir_scope<'ll, 'tcx>( // We generate DILocations here based on the callsite's location in the // source code. A single location in the source code usually can't // produce multiple distinct calls so this mostly works, until - // proc-macros get involved. A proc-macro can generate multiple calls + // macros get involved. A macro can generate multiple calls // at the same span, which breaks the assumption that we're going to // produce a unique DILocation for every scope we process here. We // have to explicitly add discriminators if we see inlines into the @@ -160,24 +175,29 @@ fn make_mir_scope<'ll, 'tcx>( // Note further that we can't key this hashtable on the span itself, // because these spans could have distinct SyntaxContexts. We have // to key on exactly what we're giving to LLVM. - match discriminators.entry(callsite_span.lo()) { + let inlined_at = match discriminators.entry(callsite_span.lo()) { Entry::Occupied(mut o) => { *o.get_mut() += 1; unsafe { llvm::LLVMRustDILocationCloneWithBaseDiscriminator(loc, *o.get()) } - .expect("Failed to encode discriminator in DILocation") } Entry::Vacant(v) => { v.insert(0); - loc + Some(loc) + } + }; + match inlined_at { + Some(inlined_at) => { + debug_scope.as_mut().unwrap().inlined_at = Some(inlined_at); + } + None => { + // LLVM has a maximum discriminator that it can encode (currently + // it uses 12 bits for 4096 possible values). If we exceed that + // there is little we can do but drop the debug info. + debug_scope = None; } } - }); + } - 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_position(), - }; + debug_context.scopes[scope] = debug_scope; instantiated.insert(scope); } diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs index 4b650b00bee..a8fdfbed592 100644 --- a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs +++ b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs @@ -294,12 +294,12 @@ impl<'ll, 'tcx> DebugInfoCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> { } // Initialize fn debug context (including scopes). - let empty_scope = DebugScope { + let empty_scope = Some(DebugScope { dbg_scope: self.dbg_scope_fn(instance, fn_abi, Some(llfn)), inlined_at: None, file_start_pos: BytePos(0), file_end_pos: BytePos(0), - }; + }); let mut fn_debug_context = FunctionDebugContext { scopes: IndexVec::from_elem(empty_scope, &mir.source_scopes), inlined_function_scopes: Default::default(), diff --git a/compiler/rustc_codegen_ssa/src/mir/debuginfo.rs b/compiler/rustc_codegen_ssa/src/mir/debuginfo.rs index 21d20475408..d4d7f16db55 100644 --- a/compiler/rustc_codegen_ssa/src/mir/debuginfo.rs +++ b/compiler/rustc_codegen_ssa/src/mir/debuginfo.rs @@ -20,7 +20,9 @@ use crate::traits::*; pub struct FunctionDebugContext<'tcx, S, L> { /// Maps from source code to the corresponding debug info scope. - pub scopes: IndexVec<mir::SourceScope, DebugScope<S, L>>, + /// May be None if the backend is not capable of representing the scope for + /// some reason. + pub scopes: IndexVec<mir::SourceScope, Option<DebugScope<S, L>>>, /// Maps from an inlined function to its debug info declaration. pub inlined_function_scopes: FxHashMap<Instance<'tcx>, S>, @@ -231,7 +233,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { &self, source_info: mir::SourceInfo, ) -> Option<(Bx::DIScope, Option<Bx::DILocation>, Span)> { - let scope = &self.debug_context.as_ref()?.scopes[source_info.scope]; + let scope = &self.debug_context.as_ref()?.scopes[source_info.scope]?; let span = hygiene::walk_chain_collapsed(source_info.span, self.mir.span); Some((scope.adjust_dbg_scope_for_span(self.cx, span), scope.inlined_at, span)) } |