Merge pull request #4145 from rust-lang/rustup-2025-01-23

Automatic Rustup

6 files changed, 47 insertions, 44 deletions

diff --git a/compiler/rustc_codegen_llvm/src/common.rs b/compiler/rustc_codegen_llvm/src/common.rs
index adfe8aeb5c5..b4e9b9f44f4 100644
--- a/compiler/rustc_codegen_llvm/src/common.rs
+++ b/compiler/rustc_codegen_llvm/src/common.rs
@@ -126,6 +126,10 @@ impl<'ll, 'tcx> ConstCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
         unsafe { llvm::LLVMGetUndef(t) }
     }
 
+    fn is_undef(&self, v: &'ll Value) -> bool {
+        unsafe { llvm::LLVMIsUndef(v) == True }
+    }
+
     fn const_poison(&self, t: &'ll Type) -> &'ll Value {
         unsafe { llvm::LLVMGetPoison(t) }
     }
diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs
index 65345751842..91283a5944e 100644
--- a/compiler/rustc_codegen_llvm/src/context.rs
+++ b/compiler/rustc_codegen_llvm/src/context.rs
@@ -751,7 +751,6 @@ impl<'ll, 'tcx> MiscCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
         } else {
             // If the symbol already exists, it is an error: for example, the user wrote
             // #[no_mangle] extern "C" fn main(..) {..}
-            // instead of #[start]
             None
         }
     }
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 e545ce386ed..11eb9651af6 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/create_scope_map.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/create_scope_map.rs
@@ -9,7 +9,7 @@ use rustc_middle::mir::{Body, SourceScope};
 use rustc_middle::ty::layout::{FnAbiOf, HasTypingEnv};
 use rustc_middle::ty::{self, Instance};
 use rustc_session::config::DebugInfo;
-use rustc_span::{BytePos, hygiene};
+use rustc_span::{BytePos, DUMMY_SP, hygiene};
 
 use super::metadata::file_metadata;
 use super::utils::DIB;
@@ -85,23 +85,15 @@ fn make_mir_scope<'ll, 'tcx>(
             discriminators,
             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;
-        }
+        debug_context.scopes[parent]
     } else {
         // The root is the function itself.
         let file = cx.sess().source_map().lookup_source_file(mir.span.lo());
-        debug_context.scopes[scope] = Some(DebugScope {
+        debug_context.scopes[scope] = DebugScope {
             file_start_pos: file.start_pos,
             file_end_pos: file.end_position(),
-            ..debug_context.scopes[scope].unwrap()
-        });
+            ..debug_context.scopes[scope]
+        };
         instantiated.insert(scope);
         return;
     };
@@ -112,7 +104,7 @@ 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] = Some(parent_scope);
+        debug_context.scopes[scope] = parent_scope;
         instantiated.insert(scope);
         return;
     }
@@ -145,14 +137,7 @@ fn make_mir_scope<'ll, 'tcx>(
         },
     };
 
-    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 inlined_at = scope_data.inlined.map(|(_, callsite_span)| {
         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);
@@ -175,29 +160,29 @@ 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.
-        let inlined_at = match discriminators.entry(callsite_span.lo()) {
+        match discriminators.entry(callsite_span.lo()) {
             Entry::Occupied(mut o) => {
                 *o.get_mut() += 1;
+                // NB: We have to emit *something* here or we'll fail LLVM IR verification
+                // in at least some circumstances (see issue #135322) so if the required
+                // discriminant cannot be encoded fall back to the dummy location.
                 unsafe { llvm::LLVMRustDILocationCloneWithBaseDiscriminator(loc, *o.get()) }
+                    .unwrap_or_else(|| {
+                        cx.dbg_loc(callsite_scope, parent_scope.inlined_at, DUMMY_SP)
+                    })
             }
             Entry::Vacant(v) => {
                 v.insert(0);
-                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;
+                loc
             }
         }
-    }
+    });
 
-    debug_context.scopes[scope] = debug_scope;
+    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(),
+    };
     instantiated.insert(scope);
 }
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
index 88e43e1c678..8d782a618fc 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs
@@ -442,7 +442,7 @@ pub(crate) fn type_di_node<'ll, 'tcx>(cx: &CodegenCx<'ll, 'tcx>, t: Ty<'tcx>) ->
         // (or if there is no allocator argument).
         ty::Adt(def, args)
             if def.is_box()
-                && args.get(1).map_or(true, |arg| cx.layout_of(arg.expect_ty()).is_1zst()) =>
+                && args.get(1).is_none_or(|arg| cx.layout_of(arg.expect_ty()).is_1zst()) =>
         {
             build_pointer_or_reference_di_node(cx, t, t.expect_boxed_ty(), unique_type_id)
         }
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
index 755f4816acf..e6778411365 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
@@ -295,12 +295,12 @@ impl<'ll, 'tcx> DebugInfoCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
         }
 
         // Initialize fn debug context (including scopes).
-        let empty_scope = Some(DebugScope {
+        let empty_scope = 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_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index ec6c84f6f25..009d15a932f 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -741,8 +741,11 @@ pub mod debuginfo {
     pub type DIEnumerator = DIDescriptor;
     pub type DITemplateTypeParameter = DIDescriptor;
 
-    // These values **must** match with LLVMRustDIFlags!!
     bitflags! {
+        /// Must match the layout of `LLVMDIFlags` in the LLVM-C API.
+        ///
+        /// Each value declared here must also be covered by the static
+        /// assertions in `RustWrapper.cpp` used by `fromRust(LLVMDIFlags)`.
         #[repr(transparent)]
         #[derive(Clone, Copy, Default)]
         pub struct DIFlags: u32 {
@@ -752,7 +755,7 @@ pub mod debuginfo {
             const FlagPublic              = 3;
             const FlagFwdDecl             = (1 << 2);
             const FlagAppleBlock          = (1 << 3);
-            const FlagBlockByrefStruct    = (1 << 4);
+            const FlagReservedBit4        = (1 << 4);
             const FlagVirtual             = (1 << 5);
             const FlagArtificial          = (1 << 6);
             const FlagExplicit            = (1 << 7);
@@ -763,10 +766,21 @@ pub mod debuginfo {
             const FlagStaticMember        = (1 << 12);
             const FlagLValueReference     = (1 << 13);
             const FlagRValueReference     = (1 << 14);
-            const FlagExternalTypeRef     = (1 << 15);
+            const FlagReserved            = (1 << 15);
+            const FlagSingleInheritance   = (1 << 16);
+            const FlagMultipleInheritance = (2 << 16);
+            const FlagVirtualInheritance  = (3 << 16);
             const FlagIntroducedVirtual   = (1 << 18);
             const FlagBitField            = (1 << 19);
             const FlagNoReturn            = (1 << 20);
+            // The bit at (1 << 21) is unused, but was `LLVMDIFlagMainSubprogram`.
+            const FlagTypePassByValue     = (1 << 22);
+            const FlagTypePassByReference = (1 << 23);
+            const FlagEnumClass           = (1 << 24);
+            const FlagThunk               = (1 << 25);
+            const FlagNonTrivial          = (1 << 26);
+            const FlagBigEndian           = (1 << 27);
+            const FlagLittleEndian        = (1 << 28);
         }
     }
 
@@ -918,6 +932,7 @@ unsafe extern "C" {
     pub fn LLVMMetadataTypeInContext(C: &Context) -> &Type;
 
     // Operations on all values
+    pub fn LLVMIsUndef(Val: &Value) -> Bool;
     pub fn LLVMTypeOf(Val: &Value) -> &Type;
     pub fn LLVMGetValueName2(Val: &Value, Length: *mut size_t) -> *const c_char;
     pub fn LLVMSetValueName2(Val: &Value, Name: *const c_char, NameLen: size_t);