[Coroutine][DebugInfo] Update the linkage name of the declaration of coro-split functions in the debug info.

llvm/include/llvm/IR/DebugInfoMetadata.h

@@ -1878,6 +1878,7 @@ class DISubprogram : public DILocalScope {
   DISubprogram *getDeclaration() const {
     return cast_or_null<DISubprogram>(getRawDeclaration());
   }
+  void replaceDeclaration(DISubprogram *Decl) { replaceOperandWith(6, Decl); }
   DINodeArray getRetainedNodes() const {
     return cast_or_null<MDTuple>(getRawRetainedNodes());
   }

llvm/lib/Transforms/Coroutines/CoroSplit.cpp

@@ -945,9 +945,22 @@ void CoroCloner::create() {
     // abstract specification, since the DWARF backend expects the
     // abstract specification to contain the linkage name and asserts
     // that they are identical.
-    if (!SP->getDeclaration() && SP->getUnit() &&
-        SP->getUnit()->getSourceLanguage() == dwarf::DW_LANG_Swift)
+    if (SP->getUnit() &&
+        SP->getUnit()->getSourceLanguage() == dwarf::DW_LANG_Swift) {
       SP->replaceLinkageName(MDString::get(Context, NewF->getName()));
+      if (auto *Decl = SP->getDeclaration()) {
+        auto *NewDecl = DISubprogram::get(
+            Decl->getContext(), Decl->getScope(), Decl->getName(),
+            NewF->getName(), Decl->getFile(), Decl->getLine(), Decl->getType(),
+            Decl->getScopeLine(), Decl->getContainingType(),
+            Decl->getVirtualIndex(), Decl->getThisAdjustment(),
+            Decl->getFlags(), Decl->getSPFlags(), Decl->getUnit(),
+            Decl->getTemplateParams(), nullptr, Decl->getRetainedNodes(),
+            Decl->getThrownTypes(), Decl->getAnnotations(),
+            Decl->getTargetFuncName());
+        SP->replaceDeclaration(NewDecl);
+      }
+    }
   }
 
   NewF->setLinkage(savedLinkage);

llvm/test/Transforms/Coroutines/coro-async-declaration.ll

@@ -0,0 +1,122 @@
+; RUN: opt < %s -passes='module(coro-early),cgscc(coro-split,simplifycfg)' -S | FileCheck %s
+
+; We want to check that updating the declaration when updating the linkage name of a DISubporgram with a declaration.
+
+; Original source code:
+; public enum Foo {
+;   public func bar() async {
+;     await f()
+;   }
+; }
+; public func f() async {}
+
+
+target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx12.0.0"
+
+%swift.async_func_pointer = type <{ i32, i32 }>
+
+@"$s3foo3FooO3baryyYaFTu" = global %swift.async_func_pointer <{ i32 trunc (i64 sub (i64 ptrtoint (ptr @"$s3foo3FooO3baryyYaF" to i64), i64 ptrtoint (ptr @"$s3foo3FooO3baryyYaFTu" to i64)) to i32), i32 16 }>, align 8
+@"$s3foo1fyyYaFTu" = global %swift.async_func_pointer <{ i32 trunc (i64 sub (i64 ptrtoint (ptr @"$s3foo1fyyYaF" to i64), i64 ptrtoint (ptr @"$s3foo1fyyYaFTu" to i64)) to i32), i32 16 }>, align 8
+
+define swifttailcc void @"$s3foo3FooO3baryyYaF"(ptr swiftasync %0) !dbg !5 {
+entry:
+  %1 = alloca ptr, align 8
+  %2 = call token @llvm.coro.id.async(i32 16, i32 16, i32 0, ptr @"$s3foo3FooO3baryyYaFTu")
+  %3 = call ptr @llvm.coro.begin(token %2, ptr null)
+  store ptr %0, ptr %1, align 8
+  %4 = load i32, ptr getelementptr inbounds (%swift.async_func_pointer, ptr @"$s3foo1fyyYaFTu", i32 0, i32 1), align 8, !dbg !10
+  %5 = zext i32 %4 to i64, !dbg !10
+  %6 = call swiftcc ptr @swift_task_alloc(i64 %5), !dbg !10
+  %7 = load ptr, ptr %1, align 8, !dbg !10
+  %8 = getelementptr inbounds <{ ptr, ptr }>, ptr %6, i32 0, i32 0, !dbg !10
+  store ptr %7, ptr %8, align 8, !dbg !10
+  %9 = call ptr @llvm.coro.async.resume(), !dbg !10
+  %10 = getelementptr inbounds <{ ptr, ptr }>, ptr %6, i32 0, i32 1, !dbg !10
+  store ptr %9, ptr %10, align 8, !dbg !10
+  %11 = call { ptr } (i32, ptr, ptr, ...) @llvm.coro.suspend.async.sl_p0s(i32 0, ptr %9, ptr @__swift_async_resume_project_context, ptr @"$s3foo3FooO3baryyYaF.0", ptr @"$s3foo1fyyYaF", ptr %6), !dbg !10
+  %12 = extractvalue { ptr } %11, 0, !dbg !10
+  %13 = call ptr @__swift_async_resume_project_context(ptr %12), !dbg !10
+  store ptr %13, ptr %1, align 8, !dbg !10
+  call swiftcc void @swift_task_dealloc(ptr %6), !dbg !10
+  %14 = load ptr, ptr %1, align 8, !dbg !11
+  %15 = getelementptr inbounds <{ ptr, ptr }>, ptr %14, i32 0, i32 1, !dbg !11
+  %16 = load ptr, ptr %15, align 8, !dbg !11
+  %17 = load ptr, ptr %1, align 8, !dbg !11
+  %18 = call i1 (ptr, i1, ...) @llvm.coro.end.async(ptr %3, i1 false, ptr @"$s3foo3FooO3baryyYaF.0.1", ptr %16, ptr %17), !dbg !11
+  unreachable, !dbg !11
+}
+
+; Function Attrs: nounwind
+declare token @llvm.coro.id.async(i32, i32, i32, ptr) #0
+
+; Function Attrs: nounwind
+declare ptr @llvm.coro.begin(token, ptr writeonly) #0
+
+declare swifttailcc void @"$s3foo1fyyYaF"(ptr swiftasync)
+
+declare swiftcc ptr @swift_task_alloc(i64)
+
+; Function Attrs: nomerge nounwind
+declare ptr @llvm.coro.async.resume() #1
+
+define linkonce_odr hidden ptr @__swift_async_resume_project_context(ptr %0) !dbg !12 {
+entry:
+  %1 = load ptr, ptr %0, align 8, !dbg !14
+  %2 = call ptr @llvm.swift.async.context.addr(), !dbg !14
+  store ptr %1, ptr %2, align 8, !dbg !14
+  ret ptr %1, !dbg !14
+}
+
+; Function Attrs: nounwind
+declare ptr @llvm.swift.async.context.addr() #0
+
+define internal swifttailcc void @"$s3foo3FooO3baryyYaF.0"(ptr %0, ptr %1) !dbg !15 {
+entry:
+  musttail call swifttailcc void %0(ptr swiftasync %1), !dbg !16
+  ret void, !dbg !16
+}
+
+; Function Attrs: nomerge nounwind
+declare { ptr } @llvm.coro.suspend.async.sl_p0s(i32, ptr, ptr, ...) #1
+
+declare swiftcc void @swift_task_dealloc(ptr)
+
+define internal swifttailcc void @"$s3foo3FooO3baryyYaF.0.1"(ptr %0, ptr %1) !dbg !17 {
+entry:
+  musttail call swifttailcc void %0(ptr swiftasync %1), !dbg !18
+  ret void, !dbg !18
+}
+
+; Function Attrs: nounwind
+declare i1 @llvm.coro.end.async(ptr, i1, ...) #0
+
+attributes #0 = { nounwind }
+attributes #1 = { nomerge nounwind }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_Swift, file: !1, producer: "Apple Swift version 5.9-dev (LLVM 1c4b88beb62789b, Swift b00d1520f89bb7d)", isOptimized: false, runtimeVersion: 5, emissionKind: LineTablesOnly, imports: !2)
+!1 = !DIFile(filename: "foo.swift", directory: "/tmp")
+!2 = !{}
+!3 = !{i32 7, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+; CHECK-DAG: ![[DECL:[0-9]+]] = !DISubprogram({{.*}}, linkageName: "$s3foo3FooO3baryyYaF"
+; CHECK-DAG: ![[DECL_Q0:[0-9]+]] = !DISubprogram({{.*}}, linkageName: "$s3foo3FooO3baryyYaFTQ0_"
+; CHECK-DAG: distinct !DISubprogram({{.*}}, linkageName: "$s3foo3FooO3baryyYaF"{{.*}}, declaration: ![[DECL]]
+; CHECK-DAG: distinct !DISubprogram({{.*}}, linkageName: "$s3foo3FooO3baryyYaFTQ0_"{{.*}}, declaration: ![[DECL_Q0]]
+!5 = distinct !DISubprogram(name: "bar", linkageName: "$s3foo3FooO3baryyYaF", scope: !6, file: !1, line: 2, type: !8, scopeLine: 2, spFlags: DISPFlagDefinition, unit: !0, declaration: !9, retainedNodes: !2)
+!6 = !DICompositeType(tag: DW_TAG_structure_type, name: "$s3foo3FooOD", scope: !7, flags: DIFlagFwdDecl, runtimeLang: DW_LANG_Swift)
+!7 = !DIModule(scope: null, name: "foo")
+!8 = !DISubroutineType(types: null)
+!9 = !DISubprogram(name: "bar", linkageName: "$s3foo3FooO3baryyYaF", scope: !6, file: !1, line: 2, type: !8, scopeLine: 2, spFlags: 0)
+!10 = !DILocation(line: 3, column: 11, scope: !5)
+!11 = !DILocation(line: 4, column: 3, scope: !5)
+!12 = distinct !DISubprogram(linkageName: "__swift_async_resume_project_context", scope: !7, file: !13, type: !8, flags: DIFlagArtificial, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
+!13 = !DIFile(filename: "<compiler-generated>", directory: "")
+!14 = !DILocation(line: 0, scope: !12)
+!15 = distinct !DISubprogram(linkageName: "$s3foo3FooO3baryyYaF", scope: !7, file: !13, type: !8, flags: DIFlagArtificial, spFlags: DISPFlagLocalToUnit | DISPFlagDefinition, unit: !0, retainedNodes: !2)
+!16 = !DILocation(line: 0, scope: !15)
+!17 = distinct !DISubprogram(linkageName: "$s3foo3FooO3baryyYaF", scope: !7, file: !13, type: !8, flags: DIFlagArtificial, spFlags: DISPFlagLocalToUnit | DISPFlagDefinition, unit: !0, retainedNodes: !2)
+!18 = !DILocation(line: 0, scope: !17)