1 files changed, 44 insertions, 32 deletions

diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
index 40714a0afe9..9cdeae2841b 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
@@ -5,7 +5,7 @@ use rustc_codegen_ssa::mir::debuginfo::VariableKind::*;
 use self::metadata::{file_metadata, type_di_node};
 use self::metadata::{UNKNOWN_COLUMN_NUMBER, UNKNOWN_LINE_NUMBER};
 use self::namespace::mangled_name_of_instance;
-use self::utils::{create_DIArray, is_node_local_to_unit, DIB};
+use self::utils::{create_DIArray, debug_context, is_node_local_to_unit, DIB};
 
 use crate::abi::FnAbi;
 use crate::builder::Builder;
@@ -67,6 +67,8 @@ pub struct CodegenUnitDebugContext<'ll, 'tcx> {
     type_map: metadata::TypeMap<'ll, 'tcx>,
     namespace_map: RefCell<DefIdMap<&'ll DIScope>>,
     recursion_marker_type: OnceCell<&'ll DIType>,
+    /// Maps a variable (name, scope, kind (argument or local), span) to its debug information.
+    variables: RefCell<FxHashMap<(Symbol, &'ll DIScope, VariableKind, Span), &'ll DIVariable>>,
 }
 
 impl Drop for CodegenUnitDebugContext<'_, '_> {
@@ -91,6 +93,7 @@ impl<'ll, 'tcx> CodegenUnitDebugContext<'ll, 'tcx> {
             type_map: Default::default(),
             namespace_map: RefCell::new(Default::default()),
             recursion_marker_type: OnceCell::new(),
+            variables: RefCell::new(Default::default()),
         }
     }
 
@@ -292,7 +295,7 @@ impl<'ll, 'tcx> DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
         fn_abi: &FnAbi<'tcx, Ty<'tcx>>,
         llfn: &'ll Value,
         mir: &mir::Body<'tcx>,
-    ) -> Option<FunctionDebugContext<&'ll DIScope, &'ll DILocation>> {
+    ) -> Option<FunctionDebugContext<'tcx, &'ll DIScope, &'ll DILocation>> {
         if self.sess().opts.debuginfo == DebugInfo::None {
             return None;
         }
@@ -304,8 +307,11 @@ impl<'ll, 'tcx> DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
             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) };
+        let mut fn_debug_context = FunctionDebugContext {
+            scopes: IndexVec::from_elem(empty_scope, &mir.source_scopes),
+            inlined_function_scopes: Default::default(),
+            lexical_blocks: Default::default(),
+        };
 
         // Fill in all the scopes, with the information from the MIR body.
         compute_mir_scopes(self, instance, mir, &mut fn_debug_context);
@@ -606,33 +612,39 @@ impl<'ll, 'tcx> DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
         variable_kind: VariableKind,
         span: Span,
     ) -> &'ll DIVariable {
-        let loc = self.lookup_debug_loc(span.lo());
-        let file_metadata = file_metadata(self, &loc.file);
-
-        let type_metadata = type_di_node(self, variable_type);
-
-        let (argument_index, dwarf_tag) = match variable_kind {
-            ArgumentVariable(index) => (index as c_uint, DW_TAG_arg_variable),
-            LocalVariable => (0, DW_TAG_auto_variable),
-        };
-        let align = self.align_of(variable_type);
-
-        let name = variable_name.as_str();
-        unsafe {
-            llvm::LLVMRustDIBuilderCreateVariable(
-                DIB(self),
-                dwarf_tag,
-                scope_metadata,
-                name.as_ptr().cast(),
-                name.len(),
-                file_metadata,
-                loc.line,
-                type_metadata,
-                true,
-                DIFlags::FlagZero,
-                argument_index,
-                align.bytes() as u32,
-            )
-        }
+        debug_context(self)
+            .variables
+            .borrow_mut()
+            .entry((variable_name, scope_metadata, variable_kind, span))
+            .or_insert_with(|| {
+                let loc = self.lookup_debug_loc(span.lo());
+                let file_metadata = file_metadata(self, &loc.file);
+
+                let type_metadata = type_di_node(self, variable_type);
+
+                let (argument_index, dwarf_tag) = match variable_kind {
+                    ArgumentVariable(index) => (index as c_uint, DW_TAG_arg_variable),
+                    LocalVariable => (0, DW_TAG_auto_variable),
+                };
+                let align = self.align_of(variable_type);
+
+                let name = variable_name.as_str();
+                unsafe {
+                    llvm::LLVMRustDIBuilderCreateVariable(
+                        DIB(self),
+                        dwarf_tag,
+                        scope_metadata,
+                        name.as_ptr().cast(),
+                        name.len(),
+                        file_metadata,
+                        loc.line,
+                        type_metadata,
+                        true,
+                        DIFlags::FlagZero,
+                        argument_index,
+                        align.bytes() as u32,
+                    )
+                }
+            })
     }
 }