diff options
| -rw-r--r-- | compiler/rustc_mir_build/src/builder/matches/mod.rs | 58 | ||||
| -rw-r--r-- | tests/codegen/assign-desugar-debuginfo.rs | 18 |
2 files changed, 60 insertions, 16 deletions
diff --git a/compiler/rustc_mir_build/src/builder/matches/mod.rs b/compiler/rustc_mir_build/src/builder/matches/mod.rs index ea341b604e0..cf216ff73ca 100644 --- a/compiler/rustc_mir_build/src/builder/matches/mod.rs +++ b/compiler/rustc_mir_build/src/builder/matches/mod.rs @@ -13,13 +13,13 @@ use std::sync::Arc; use rustc_abi::VariantIdx; use rustc_data_structures::fx::FxIndexMap; use rustc_data_structures::stack::ensure_sufficient_stack; -use rustc_hir::{BindingMode, ByRef}; +use rustc_hir::{BindingMode, ByRef, LetStmt, LocalSource, Node}; use rustc_middle::bug; use rustc_middle::middle::region; use rustc_middle::mir::{self, *}; use rustc_middle::thir::{self, *}; use rustc_middle::ty::{self, CanonicalUserTypeAnnotation, Ty}; -use rustc_span::{BytePos, Pos, Span, Symbol}; +use rustc_span::{BytePos, Pos, Span, Symbol, sym}; use tracing::{debug, instrument}; use crate::builder::ForGuard::{self, OutsideGuard, RefWithinGuard}; @@ -2796,13 +2796,15 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { )))), }; let for_arm_body = self.local_decls.push(local); - self.var_debug_info.push(VarDebugInfo { - name, - source_info: debug_source_info, - value: VarDebugInfoContents::Place(for_arm_body.into()), - composite: None, - argument_index: None, - }); + if self.should_emit_debug_info_for_binding(name, var_id) { + self.var_debug_info.push(VarDebugInfo { + name, + source_info: debug_source_info, + value: VarDebugInfoContents::Place(for_arm_body.into()), + composite: None, + argument_index: None, + }); + } let locals = if has_guard.0 { let ref_for_guard = self.local_decls.push(LocalDecl::<'tcx> { // This variable isn't mutated but has a name, so has to be @@ -2815,13 +2817,15 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { BindingForm::RefForGuard, ))), }); - self.var_debug_info.push(VarDebugInfo { - name, - source_info: debug_source_info, - value: VarDebugInfoContents::Place(ref_for_guard.into()), - composite: None, - argument_index: None, - }); + if self.should_emit_debug_info_for_binding(name, var_id) { + self.var_debug_info.push(VarDebugInfo { + name, + source_info: debug_source_info, + value: VarDebugInfoContents::Place(ref_for_guard.into()), + composite: None, + argument_index: None, + }); + } LocalsForNode::ForGuard { ref_for_guard, for_arm_body } } else { LocalsForNode::One(for_arm_body) @@ -2829,4 +2833,26 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { debug!(?locals); self.var_indices.insert(var_id, locals); } + + /// Some bindings are introduced when producing HIR from the AST and don't + /// actually exist in the source. Skip producing debug info for those when + /// we can recognize them. + fn should_emit_debug_info_for_binding(&self, name: Symbol, var_id: LocalVarId) -> bool { + // For now we only recognize the output of desugaring assigns. + if name != sym::lhs { + return true; + } + + let tcx = self.tcx; + for (_, node) in tcx.hir_parent_iter(var_id.0) { + // FIXME(khuey) at what point is it safe to bail on the iterator? + // Can we stop at the first non-Pat node? + if matches!(node, Node::LetStmt(&LetStmt { source: LocalSource::AssignDesugar(_), .. })) + { + return false; + } + } + + true + } } diff --git a/tests/codegen/assign-desugar-debuginfo.rs b/tests/codegen/assign-desugar-debuginfo.rs new file mode 100644 index 00000000000..77ee8758b3b --- /dev/null +++ b/tests/codegen/assign-desugar-debuginfo.rs @@ -0,0 +1,18 @@ +//@ compile-flags: -g -Zmir-opt-level=0 + +#![crate_type = "lib"] + +#[inline(never)] +fn swizzle(a: u32, b: u32, c: u32) -> (u32, (u32, u32)) { + (b, (c, a)) +} + +pub fn work() { + let mut a = 1; + let mut b = 2; + let mut c = 3; + (a, (b, c)) = swizzle(a, b, c); + println!("{a} {b} {c}"); +} + +// CHECK-NOT: !DILocalVariable(name: "lhs", |