DebugInfo: Ensure imported entities at the top level of an inlined function don't...

Local imported entities at the top level of a subprogram were being
handled differently from those in nested scopes - that different
handling would cause pseudo concrete out-of-line definitions to be
created (but without any of their attributes, nor an abstract_origin) in
the case where there was no real concrete definition.

These local imported entities also only appeared in the concrete
definition where those imported entities in nested scopes appear in all
cases (abstract, concrete, and inlined). This change at least makes top
level case handle the same as the others - though there's a FIXME to
improve this to /only/ emit them into the abstract origin (though this
requires more plumbing - like the abstract subprogram and variable
handling that must defer population until the end of the unit to
discover if there is an abstract origin, or only a standalone concrete
definition).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309237 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index 676c48fe5c6781de2664a9c234b7e51bea3e0a81..e4b8939f2abc7f631425f255b524a4b1bcbdd624 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -336,23 +336,15 @@ void DwarfCompileUnit::constructScopeDIE(
     if (DD->isLexicalScopeDIENull(Scope))
       return;
 
-    unsigned ChildScopeCount;
+    bool HasNonScopeChildren = false;
 
     // We create children here when we know the scope DIE is not going to be
     // null and the children will be added to the scope DIE.
-    createScopeChildrenDIE(Scope, Children, &ChildScopeCount);
-
-    // Skip imported directives in gmlt-like data.
-    if (!includeMinimalInlineScopes()) {
-      // There is no need to emit empty lexical block DIE.
-      for (const auto *IE : ImportedEntities[DS])
-        Children.push_back(
-            constructImportedEntityDIE(cast<DIImportedEntity>(IE)));
-    }
+    createScopeChildrenDIE(Scope, Children, &HasNonScopeChildren);
 
     // If there are only other scopes as children, put them directly in the
     // parent instead, as this scope would serve no purpose.
-    if (Children.size() == ChildScopeCount) {
+    if (!HasNonScopeChildren) {
       FinalChildren.insert(FinalChildren.end(),
                            std::make_move_iterator(Children.begin()),
                            std::make_move_iterator(Children.end()));
@@ -557,20 +549,27 @@ DIE *DwarfCompileUnit::constructVariableDIE(DbgVariable &DV,
 
 DIE *DwarfCompileUnit::createScopeChildrenDIE(LexicalScope *Scope,
                                               SmallVectorImpl<DIE *> &Children,
-                                              unsigned *ChildScopeCount) {
+                                              bool *HasNonScopeChildren) {
+  assert(Children.empty());
   DIE *ObjectPointer = nullptr;
 
   for (DbgVariable *DV : DU->getScopeVariables().lookup(Scope))
     Children.push_back(constructVariableDIE(*DV, *Scope, ObjectPointer));
 
-  unsigned ChildCountWithoutScopes = Children.size();
+  // Skip imported directives in gmlt-like data.
+  if (!includeMinimalInlineScopes()) {
+    // There is no need to emit empty lexical block DIE.
+    for (const auto *IE : ImportedEntities[Scope->getScopeNode()])
+      Children.push_back(
+          constructImportedEntityDIE(cast<DIImportedEntity>(IE)));
+  }
+
+  if (HasNonScopeChildren)
+    *HasNonScopeChildren = !Children.empty();
 
   for (LexicalScope *LS : Scope->getChildren())
     constructScopeDIE(LS, Children);
 
-  if (ChildScopeCount)
-    *ChildScopeCount = Children.size() - ChildCountWithoutScopes;
-
   return ObjectPointer;
 }
 

diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h
index e38672792867367e9bda3ba0ea52edc5a45ca0d1..93b3504d9f0dd109ddf8d6be7134b8a5d0d782b4 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h
+++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.h
@@ -181,7 +181,7 @@ public:
   /// A helper function to create children of a Scope DIE.
   DIE *createScopeChildrenDIE(LexicalScope *Scope,
                               SmallVectorImpl<DIE *> &Children,
-                              unsigned *ChildScopeCount = nullptr);
+                              bool *HasNonScopeChildren = nullptr);
 
   /// \brief Construct a DIE for this subprogram scope.
   void constructSubprogramScopeDIE(const DISubprogram *Sub, LexicalScope *Scope);

diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 70fe1e233ba2fb0df39d6c91d2b7df2001e9bf3c..d2085e341904308918e4a10d0f99a7cb6b340526 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -494,6 +494,8 @@ DwarfDebug::getOrCreateDwarfCompileUnit(const DICompileUnit *DIUnit) {
 
 void DwarfDebug::constructAndAddImportedEntityDIE(DwarfCompileUnit &TheCU,
                                                   const DIImportedEntity *N) {
+  if (isa<DILocalScope>(N->getScope()))
+    return;
   if (DIE *D = TheCU.getOrCreateContextDIE(N->getScope()))
     D->addChild(TheCU.constructImportedEntityDIE(N));
 }

diff --git a/test/DebugInfo/Generic/imported-name-inlined.ll b/test/DebugInfo/Generic/imported-name-inlined.ll
new file mode 100644 (file)
index 0000000..1da2d14
--- /dev/null
+++ b/test/DebugInfo/Generic/imported-name-inlined.ll
@@ -0,0 +1,69 @@
+; REQUIRES: object-emission
+
+; RUN: %llc_dwarf -O0 -filetype=obj < %s | llvm-dwarfdump -debug-dump=info - | FileCheck --implicit-check-not "{{DW_TAG|NULL}}" %s
+
+; Generated from the following source:
+; namespace ns {
+; void f();
+; }
+; inline __attribute__((always_inline)) void f1() {
+;   using ns::f;
+;   f();
+; }
+; void f2() { f1(); }
+
+; Ensure that top level imported declarations don't produce an extra degenerate
+; concrete subprogram definition.
+
+; FIXME: imported entities should only be emitted to the abstract origin if one is present
+
+; CHECK: DW_TAG_compile_unit
+; CHECK:   DW_TAG_subprogram
+; CHECK:     DW_AT_name {{.*}} "f1"
+; CHECK:     DW_TAG_imported_declaration
+; CHECK:     NULL
+; CHECK:   DW_TAG_namespace
+; CHECK:     DW_TAG_subprogram
+; CHECK:     NULL
+; CHECK:   DW_TAG_subprogram
+; CHECK:     DW_AT_name {{.*}} "f2"
+; CHECK:     DW_TAG_inlined_subroutine
+; CHECK:       DW_TAG_imported_declaration
+; CHECK:       NULL
+; CHECK:     NULL
+; CHECK:   NULL
+
+; Function Attrs: noinline optnone uwtable
+define void @_Z2f2v() #0 !dbg !14 {
+entry:
+  call void @_ZN2ns1fEv(), !dbg !15
+  ret void, !dbg !17
+}
+
+declare void @_ZN2ns1fEv() #1
+
+attributes #0 = { noinline optnone uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!10, !11, !12}
+!llvm.ident = !{!13}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 6.0.0 (trunk 309061) (llvm/trunk 309076)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, imports: !3)
+!1 = !DIFile(filename: "imported-name-inlined.cpp", directory: "/usr/local/google/home/blaikie/dev/scratch")
+!2 = !{}
+!3 = !{!4}
+!4 = !DIImportedEntity(tag: DW_TAG_imported_declaration, scope: !5, entity: !8, file: !1, line: 5)
+!5 = distinct !DISubprogram(name: "f1", linkageName: "_Z2f1v", scope: !1, file: !1, line: 4, type: !6, isLocal: false, isDefinition: true, scopeLine: 4, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !2)
+!6 = !DISubroutineType(types: !7)
+!7 = !{null}
+!8 = !DISubprogram(name: "f", linkageName: "_ZN2ns1fEv", scope: !9, file: !1, line: 2, type: !6, isLocal: false, isDefinition: false, flags: DIFlagPrototyped, isOptimized: false)
+!9 = !DINamespace(name: "ns", scope: null)
+!10 = !{i32 2, !"Dwarf Version", i32 4}
+!11 = !{i32 2, !"Debug Info Version", i32 3}
+!12 = !{i32 1, !"wchar_size", i32 4}
+!13 = !{!"clang version 6.0.0 (trunk 309061) (llvm/trunk 309076)"}
+!14 = distinct !DISubprogram(name: "f2", linkageName: "_Z2f2v", scope: !1, file: !1, line: 8, type: !6, isLocal: false, isDefinition: true, scopeLine: 8, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !2)
+!15 = !DILocation(line: 6, column: 3, scope: !5, inlinedAt: !16)
+!16 = distinct !DILocation(line: 8, column: 13, scope: !14)
+!17 = !DILocation(line: 8, column: 19, scope: !14)

diff --git a/test/DebugInfo/Generic/namespace.ll b/test/DebugInfo/Generic/namespace.ll
index 5a8f652631922add1b6d580e30046b24b270feb8..8b2ef0b97a7a3a7365cde0c911afd1ae7381f6b4 100644 (file)
--- a/test/DebugInfo/Generic/namespace.ll
+++ b/test/DebugInfo/Generic/namespace.ll
@@ -23,6 +23,11 @@
 ; CHECK-NOT: NULL
 ; CHECK: [[BAR:0x[0-9a-f]*]]:{{ *}}DW_TAG_structure_type
 ; CHECK-NEXT: DW_AT_name{{.*}}= "bar"
+; CHECK: DW_TAG_subprogram
+; CHECK-NOT: DW_TAG
+; CHECK: DW_AT_MIPS_linkage_name
+; CHECK-NOT: DW_TAG
+; CHECK: DW_AT_name{{.*}}= "f1"
 ; CHECK: [[FUNC1:.*]]: DW_TAG_subprogram
 ; CHECK-NOT: DW_TAG
 ; CHECK: DW_AT_MIPS_linkage_name
@@ -45,11 +50,6 @@
 ; CHECK-NOT: DW_TAG
 ; CHECK: DW_AT_name{{.*}}= "func_fwd"
 ; CHECK-NOT: DW_AT_declaration
-; CHECK: DW_TAG_subprogram
-; CHECK-NOT: DW_TAG
-; CHECK: DW_AT_MIPS_linkage_name
-; CHECK-NOT: DW_TAG
-; CHECK: DW_AT_name{{.*}}= "f1"
 ; CHECK: NULL
 
 ; CHECK-NOT: NULL
@@ -66,6 +66,8 @@
 ; CHECK-NEXT: DW_AT_import{{.*}}=> {[[NS1]]})
 ; CHECK-NOT: NULL
 
+; CHECK: DW_TAG_subprogram
+; CHECK-NOT: {{DW_TAG|NULL}}
 ; CHECK: DW_TAG_subprogram
 ; CHECK-NOT: DW_TAG
 ; CHECK: DW_AT_MIPS_linkage_name