llvm/test/Transforms/Coroutines/coro-split-dbg-labels.ll

; Tests that we add DILabels for the suspend points.
;
; Check the generated LLVM:
; RUN: opt < %s -passes='cgscc(coro-split)' -S | FileCheck %s
;
; Check the generated DWARF debug info:
; REQUIRES: object-emission
; RUN: opt < %s -passes='cgscc(coro-split),coro-cleanup' \
; RUN:   | %llc_dwarf -O0 -filetype=obj -o - \
; RUN:   | llvm-dwarfdump - \
; RUN:   | FileCheck %s -check-prefix=DWARF
;
; Check that we don't emit any DILabel if in `LineTablesOnly` mode
; RUN: sed -e 's/emissionKind: FullDebug/emissionKind: LineTablesOnly/' %s \
; RUN:   | opt -passes='cgscc(coro-split)' -S \
; RUN:   | FileCheck %s -check-prefix=LINE-TABLE

source_filename = "coro.c"

declare void @bar(...) local_unnamed_addr #0
declare void @baz(...) local_unnamed_addr #0

; Roughly equivalent to:
;
; task f() {
;   while (true) {
;     bar();
;     co_await std::suspend_always{};
;     baz();
;     co_await std::suspend_always{};
;   }
; }

; Function Attrs: nounwind uwtable
define ptr @f() #2 !dbg !16 {
entry:
  %0 = tail call token @llvm.coro.id(i32 0, ptr null, ptr @f, ptr null), !dbg !26
  %1 = tail call i64 @llvm.coro.size.i64(), !dbg !26
  %frame = tail call ptr @malloc(i64 %1), !dbg !26
  %2 = tail call ptr @llvm.coro.begin(token %0, ptr %frame) #3, !dbg !26
  br label %loop1, !dbg !27

loop1:                                         ; preds = %for.cond, %entry
  tail call void (...) @bar() #0, !dbg !33
  %3 = tail call token @llvm.coro.save(ptr null), !dbg !34
  %4 = tail call i8 @llvm.coro.suspend(token %3, i1 false), !dbg !34
  switch i8 %4, label %coro_Suspend [
    i8 0, label %loop2
    i8 1, label %coro_Cleanup
  ], !dbg !34

loop2:                                         ; preds = %for.cond, %entry
  tail call void (...) @baz() #0, !dbg !35
  %5 = tail call token @llvm.coro.save(ptr null), !dbg !36
  %6 = tail call i8 @llvm.coro.suspend(token %5, i1 false), !dbg !36
  switch i8 %6, label %coro_Suspend [
    i8 0, label %loop1
    i8 1, label %coro_Cleanup
  ], !dbg !36

coro_Cleanup:                                     ; preds = %for.cond
  %7 = tail call ptr @llvm.coro.free(token %0, ptr %2), !dbg !37
  tail call void @free(ptr nonnull %7), !dbg !37
  br label %coro_Suspend, !dbg !37

coro_Suspend:                                     ; preds = %for.cond, %if.then, %coro_Cleanup
  tail call i1 @llvm.coro.end(ptr null, i1 false, token none) #3, !dbg !40
  ret ptr %2, !dbg !41
}

; Check that the resume function contains the `#dbg_label` instructions.
; CHECK-LABEL:   define ptr @f() #1 !dbg !6 {
; CHECK:         resume.0:        ; preds = %resume.entry
; CHECK-NEXT:        #dbg_label(![[RESUME_0:[0-9]+]], !{{[0-9]+}})
; CHECK:         resume.1:        ; preds = %resume.entry
; CHECK-NEXT:        #dbg_label(![[RESUME_1:[0-9]+]], !{{[0-9]+}})

; Check that the destroy function contains the `#dbg_label` instructions.
; CHECK-LABEL:   define internal fastcc void @f.destroy({{.*}}) #1 !dbg !38 {
; CHECK:         resume.0:        ; preds = %resume.entry
; CHECK-NEXT:        #dbg_label(![[DESTROY_0:[0-9]+]], !{{[0-9]+}})
; CHECK:         resume.1:        ; preds = %resume.entry
; CHECK-NEXT:        #dbg_label(![[DESTROY_1:[0-9]+]], !{{[0-9]+}})

; Check that the DILabels are correct.
; CHECK: ![[RESUME_0]] = !DILabel(scope: !{{[0-9]+}}, name: "__coro_resume_0", file: !{{[0-9]*}}, line: 12, column: 6, isArtificial: true, coroSuspendIdx: 0)
; CHECK: ![[RESUME_1]] = !DILabel(scope: !{{[0-9]+}}, name: "__coro_resume_1", file: !{{[0-9]*}}, line: 14, column: 6, isArtificial: true, coroSuspendIdx: 1)
; CHECK: ![[DESTROY_0]] = !DILabel(scope: !{{[0-9]+}}, name: "__coro_resume_0", file: !{{[0-9]*}}, line: 12, column: 6, isArtificial: true, coroSuspendIdx: 0)
; CHECK: ![[DESTROY_1]] = !DILabel(scope: !{{[0-9]+}}, name: "__coro_resume_1", file: !{{[0-9]*}}, line: 14, column: 6, isArtificial: true, coroSuspendIdx: 1)

; Check the we do not emit any DILabels in LineTablesOnly mode.
; The DWARF emitter cannot handle this and would run into an assertion.
; LINE-TABLE: !DICompileUnit{{.*}}LineTablesOnly
; LINE-TABLE-NOT: DILabel


; DWARF:        {{.*}}DW_TAG_label
; DWARF-NEXT:    DW_AT_name ("__coro_resume_0")
; DWARF-NEXT:    DW_AT_decl_file
; DWARF-NEXT:    DW_AT_decl_line    (12)
; DWARF-NEXT:    DW_AT_decl_column  (6)
; DWARF-NEXT:    DW_AT_artificial   (true)
; DWARF-NEXT:    DW_AT_LLVM_coro_suspend_idx (0x00)
; DWARF-NEXT:    DW_AT_low_pc


; Function Attrs: argmemonly nounwind readonly
declare token @llvm.coro.id(i32, ptr readnone, ptr nocapture readonly, ptr) #4

; Function Attrs: nounwind
declare noalias ptr @malloc(i64) local_unnamed_addr #0
declare i64 @llvm.coro.size.i64() #1
declare ptr @llvm.coro.begin(token, ptr writeonly) #0
declare token @llvm.coro.save(ptr) #0
declare i8 @llvm.coro.suspend(token, i1) #0
declare ptr @llvm.coro.free(token, ptr nocapture readonly) #4
declare void @free(ptr nocapture) local_unnamed_addr #0
declare i1 @llvm.coro.end(ptr, i1, token) #0

attributes #0 = { nounwind }
attributes #1 = { nounwind readnone }
attributes #2 = { nounwind uwtable presplitcoroutine }
attributes #3 = { noduplicate }
attributes #4 = { argmemonly nounwind readonly }

!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!3, !4}
!llvm.ident = !{!5}

!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 4.0.0 - manually edited", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
!1 = !DIFile(filename: "coro.c", directory: "/home/gor/build/bin")
!2 = !{}
!3 = !{i32 2, !"Dwarf Version", i32 4}
!4 = !{i32 2, !"Debug Info Version", i32 3}
!5 = !{!"clang version 4.0.0 - manually edited"}
!9 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
!16 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 8, type: !17, isLocal: false, isDefinition: true, scopeLine: 8, isOptimized: true, unit: !0, retainedNodes: !20)
!17 = !DISubroutineType(types: !18)
!18 = !{!19}
!19 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64, align: 64)
!20 = !{!21, !22, !24}
!21 = !DILocalVariable(name: "coro_hdl", scope: !16, file: !1, line: 9, type: !19)
!22 = !DILocalVariable(name: "i", scope: !23, file: !1, line: 11, type: !9)
!23 = distinct !DILexicalBlock(scope: !16, file: !1, line: 11, column: 3)
!24 = !DILocalVariable(name: "coro_mem", scope: !16, file: !1, line: 16, type: !19)
!26 = !DILocation(line: 9, column: 3, scope: !16)
!27 = !DILocation(line: 10, column: 8, scope: !23)
!33 = !DILocation(line: 11, column: 6, scope: !23)
!34 = !DILocation(line: 12, column: 6, scope: !23)
!35 = !DILocation(line: 13, column: 6, scope: !23)
!36 = !DILocation(line: 14, column: 6, scope: !23)
!37 = !DILocation(line: 16, column: 3, scope: !16)
!40 = !DILocation(line: 16, column: 3, scope: !16)
!41 = !DILocation(line: 17, column: 1, scope: !16)