[msan] Use Debug Info to point to affected fields

[vitalybuka]

rebase

[dblaikie]

The code change looks like it's creating inlinedAt scopes, but none of the test cases seem to test any inlinedAt debug info? Looks like this is lacking some test coverage - could you add some?

clang/lib/CodeGen/CGClass.cpp

void Emit(CodeGenFunction &CGF, Flags flags) override {
       LValue LV = CGF.EmitLValueForField(ThisLV, field);
       assert(LV.isSimple());
 
       CGF.emitDestroy(LV.getAddress(CGF), field->getType(), destroyer,
                       flags.isForNormalCleanup() && useEHCleanupForArray);
     }
   };
 
+  class DeclAsInlineDebugLocation {
+    CGDebugInfo *DI;
+    llvm::MDNode *InlinedAt;
+    llvm::Optional<ApplyDebugLocation> Location;
+
+  public:
+    DeclAsInlineDebugLocation(CodeGenFunction &CGF, const NamedDecl &Decl)
+        : DI(CGF.getDebugInfo()) {
+      if (!DI)
+        return;
+      InlinedAt = DI->getInlinedAt();
+      DI->setInlinedAt(CGF.Builder.getCurrentDebugLocation());
+      Location.emplace(CGF, Decl.getLocation());
+    }
+
+    ~DeclAsInlineDebugLocation() {
+      if (!DI)
+        return;
+      Location.reset();
+      DI->setInlinedAt(InlinedAt);
+    }
+  };
+
   static void EmitSanitizerDtorCallback(
       CodeGenFunction &CGF, StringRef Name, llvm::Value *Ptr,
       llvm::Optional<CharUnits::QuantityType> PoisonSize = {}) {
     CodeGenFunction::SanitizerScope SanScope(&CGF);
     // Pass in void pointer and size of region as arguments to runtime
     // function
     SmallVector<llvm::Value *, 2> Args = {
         CGF.Builder.CreateBitCast(Ptr, CGF.VoidPtrTy)};
void Emit(CodeGenFunction &CGF, Flags flags) override {
 
       const ASTRecordLayout &BaseLayout =
           CGF.getContext().getASTRecordLayout(BaseClass);
       CharUnits BaseSize = BaseLayout.getSize();
 
       if (!BaseSize.isPositive())
         return;
 
+      // Use the base class declaration location as inline DebugLocation. All
+      // fields of the class are destroyed.
+      DeclAsInlineDebugLocation InlineHere(CGF, *BaseClass);
       EmitSanitizerDtorFieldsCallback(CGF, Addr.getPointer(),
                                       BaseSize.getQuantity());
 
       // Prevent the current stack frame from disappearing from the stack trace.
       CGF.CurFn->addFnAttr("disable-tail-calls", "true");
     }
   };
 
void Emit(CodeGenFunction &CGF, Flags flags) override {
       } else {
         PoisonEnd =
             Context.toCharUnitsFromBits(Layout.getFieldOffset(EndIndex));
       }
       CharUnits PoisonSize = PoisonEnd - PoisonStart;
       if (!PoisonSize.isPositive())
         return;
 
+      // Use the top field declaration location as inline DebugLocation.
+      DeclAsInlineDebugLocation InlineHere(
+          CGF, **std::next(Dtor->getParent()->field_begin(), StartIndex));
       EmitSanitizerDtorFieldsCallback(CGF, OffsetPtr, PoisonSize.getQuantity());
 
       // Prevent the current stack frame from disappearing from the stack trace.
       CGF.CurFn->addFnAttr("disable-tail-calls", "true");
     }
   };
 
  class SanitizeDtorVTable final : public EHScopeStack::Cleanup {

clang/test/CodeGenCXX/sanitize-dtor-bit-field.cpp

 // CHECK: ret void
 
 // CHECK-LABEL: define {{.*}}AdjacentD2Ev
 // CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}i64 1{{.*}}, !dbg ![[DI4:[0-9]+]]
 // CHECK: ret void
 
 // CHECK-LABEL: !DIFile{{.*}}cpp
 
-// CHECK-DAG: ![[DI1]] = {{.*}}line: [[@LINE-68]]
-// CHECK-DAG: ![[DI2]] = {{.*}}line: [[@LINE-53]]
-// CHECK-DAG: ![[DI3]] = {{.*}}line: [[@LINE-41]]
-// CHECK-DAG: ![[DI4]] = {{.*}}line: [[@LINE-28]]
+// CHECK-DAG: ![[DI1]] = {{.*}}line: [[@LINE-78]]
+// CHECK-DAG: ![[DI2]] = {{.*}}line: [[@LINE-54]]
+// CHECK-DAG: ![[DI3]] = {{.*}}line: [[@LINE-46]]
+// CHECK-DAG: ![[DI4]] = {{.*}}line: [[@LINE-30]]

clang/test/CodeGenCXX/sanitize-dtor-callback.cpp

 // CHECK: ret void
 
 // CHECK-LABEL: define {{.*}}Defaulted_Non_TrivialD2Ev
 // CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, !dbg ![[DI3:[0-9]+]]
 // CHECK: ret void
 
 // CHECK-LABEL: !DIFile{{.*}}cpp
 
-// CHECK-DAG: ![[DI1]] = {{.*}}line: [[@LINE-64]]
-// CHECK-DAG: ![[DI2]] = {{.*}}line: [[@LINE-55]]
-// CHECK-DAG: ![[DI3]] = {{.*}}line: [[@LINE-33]]
+// CHECK-DAG: ![[DI1]] = {{.*}}line: [[@LINE-65]]
+// CHECK-DAG: ![[DI2]] = {{.*}}line: [[@LINE-56]]
+// CHECK-DAG: ![[DI3]] = {{.*}}line: [[@LINE-34]]

clang/test/CodeGenCXX/sanitize-dtor-derived-class.cpp

 
 // CHECK-LABEL: define {{.*}}BaseD0Ev
 // CHECK: call void {{.*}}BaseD1Ev
 // CHECK: ret void
 
 // Poison members and vtable ptr.
 // CHECK-LABEL: define {{.*}}BaseD2Ev
 // CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, !dbg ![[DI1:[0-9]+]]
-// CHECK: call void @__sanitizer_dtor_callback_vptr({{.*}}){{.*}}, !dbg ![[DI1]]
+// CHECK: call void @__sanitizer_dtor_callback_vptr({{.*}}){{.*}}, !dbg ![[DI2:[0-9]+]]
 // CHECK: ret void
 
 // Poison members and destroy non-virtual base.
 // CHECK-LABEL: define {{.*}}DerivedD2Ev
 // CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, !dbg ![[DI3:[0-9]+]]
 // CHECK: call void {{.*}}BaseD2Ev
-// CHECK: call void @__sanitizer_dtor_callback_vptr({{.*}}){{.*}}, !dbg ![[DI3]]
+// CHECK: call void @__sanitizer_dtor_callback_vptr({{.*}}){{.*}}, !dbg ![[DI4:[0-9]+]]
 // CHECK: ret void
 
 // CHECK-LABEL: !DIFile{{.*}}cpp
 
-// CHECK-DAG: ![[DI1]] = {{.*}}line: [[@LINE-49]]
-// CHECK-DAG: ![[DI3]] = {{.*}}line: [[@LINE-39]]
+// CHECK-DAG: ![[DI1]] = {{.*}}line: [[@LINE-55]]
+// CHECK-DAG: ![[DI2]] = {{.*}}line: [[@LINE-50]]
+// CHECK-DAG: ![[DI3]] = {{.*}}line: [[@LINE-46]]
+// CHECK-DAG: ![[DI4]] = {{.*}}line: [[@LINE-41]]

clang/test/CodeGenCXX/sanitize-dtor-nontrivial-virtual-base.cpp

 // CHECK: ret void
 
 // CHECK-LABEL: define {{.*}}ZN11VirtualBaseD0Ev
 // CHECK: ret void
 
 // poison 2 ints
 // CHECK-LABEL: define {{.*}}ZN11VirtualBaseD2Ev
 // CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, i64 8){{.*}}, !dbg ![[DI1:[0-9]+]]
-// CHECK: call void @__sanitizer_dtor_callback_vptr({{.*}}){{.*}}, !dbg ![[DI1]]
+// CHECK: call void @__sanitizer_dtor_callback_vptr({{.*}}){{.*}}{{.*}}, !dbg ![[DI2:[0-9]+]]
 // CHECK: ret void
 
 // poison int and double
 // CHECK-LABEL: define {{.*}}ZN4BaseD2Ev
-// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, i64 16){{.*}}, !dbg ![[DI2:[0-9]+]]
-// CHECK: call void @__sanitizer_dtor_callback_vptr({{.*}}{{.*}}, !dbg ![[DI2]]
+// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, i64 16){{.*}}, !dbg ![[DI3:[0-9]+]]
+// CHECK: call void @__sanitizer_dtor_callback_vptr({{.*}}{{.*}}, !dbg ![[DI4:[0-9]+]]
 // CHECK: ret void
 
 // poison int, ignore vector, poison int
 // CHECK-LABEL: define {{.*}}ZN7DerivedD2Ev
-// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, i64 4){{.*}}, !dbg ![[DI3:[0-9]+]]
+// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, i64 4){{.*}}, !dbg ![[DI5:[0-9]+]]
 // CHECK: call void {{.*}}ZN6VectorIiED1Ev
-// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, i64 4){{.*}}, !dbg ![[DI3]]
+// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, i64 4){{.*}}, !dbg ![[DI6:[0-9]+]]
 // CHECK: call void {{.*}}ZN4BaseD2Ev
 // CHECK: ret void
 
 // poison int
 // CHECK-LABEL: define {{.*}}ZN6VectorIiED2Ev
-// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, i64 4){{.*}}, !dbg ![[DI5:[0-9]+]]
+// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, i64 4){{.*}}, !dbg ![[DI7:[0-9]+]]
 // CHECK: ret void
 
 // CHECK-LABEL: !DIFile{{.*}}.cpp
 
 // CHECK-DAG: ![[DI0]] = {{.*}}line: [[@LINE-49]]
-// CHECK-DAG: ![[DI1]] = {{.*}}line: [[@LINE-60]]
-// CHECK-DAG: ![[DI2]] = {{.*}}line: [[@LINE-71]]
-// CHECK-DAG: ![[DI3]] = {{.*}}line: [[@LINE-52]]
-// CHECK-DAG: ![[DI5]] = {{.*}}line: [[@LINE-83]]
+// CHECK-DAG: ![[DI1]] = {{.*}}line: [[@LINE-66]]
+// CHECK-DAG: ![[DI2]] = {{.*}}line: [[@LINE-61]]
+// CHECK-DAG: ![[DI3]] = {{.*}}line: [[@LINE-78]]
+// CHECK-DAG: ![[DI5]] = {{.*}}line: [[@LINE-57]]
+// CHECK-DAG: ![[DI6]] = {{.*}}line: [[@LINE-60]]
+// CHECK-DAG: ![[DI7]] = {{.*}}line: [[@LINE-88]]

clang/test/CodeGenCXX/sanitize-dtor-trivial-base.cpp

public:
   }
 };
 
 Derived d;
 
 // Poison members, then poison the trivial base class.
 // CHECK-LABEL: define {{.*}}DerivedD2Ev
 // CHECK: %[[GEP:[0-9a-z]+]] = getelementptr i8, i8* {{.*}}, i64 16
-// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}%[[GEP]], i64 4{{.*}}, !dbg ![[DI:[0-9]+]]
-// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, i64 16{{.*}}, !dbg ![[DI]]
+// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}%[[GEP]], i64 4{{.*}}, !dbg ![[DI1:[0-9]+]]
+// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, i64 16{{.*}}, !dbg ![[DI2:[0-9]+]]
 // CHECK: ret void
 
 // CHECK-LABEL: !DIFile{{.*}}cpp
 
-// CHECK-DAG: ![[DI]] = {{.*}}line: [[@LINE-14]]
+// CHECK-DAG: ![[DI1]] = {{.*}}line: [[@LINE-16]]
+// CHECK-DAG: ![[DI2]] = {{.*}}line: [[@LINE-24]]

clang/test/CodeGenCXX/sanitize-dtor-trivial.cpp

struct Trivial {
   int b;
 };
 Trivial t;
 
 // CHECK: call void @__sanitizer_dtor_callback({{.*}}, !dbg ![[DI:[0-9]+]]
 
 // CHECK-LABEL: !DIFile{{.*}}.cpp
 
-// CHECK-DAG: ![[DI]] = {{.*}}line: [[@LINE-371]]
+// CHECK: ![[DI]] = {{.*}}line: [[@LINE-9]]

clang/test/CodeGenCXX/sanitize-dtor-vtable.cpp

 // CHECK-LABEL: define {{.*}}AD1Ev
 // CHECK: call void {{.*}}AD2Ev
 // CHECK: ret void
 
 // After invoking base dtor and dtor for virtual base, poison vtable ptr.
 // CHECK-LABEL: define {{.*}}BD1Ev
 // CHECK: call void {{.*}}BD2Ev
 // CHECK: call void {{.*}}AD2Ev
-// CHECK: call void @__sanitizer_dtor_callback_vptr({{.*}}, !dbg ![[DI1:[0-9]+]]
+// CHECK: call void @__sanitizer_dtor_callback_vptr{{.*}}, !dbg ![[DI1:[0-9]+]]
 // CHECK: ret void
 
 // Since no virtual bases, poison vtable ptr here.
 // CHECK-LABEL: define {{.*}}AD2Ev
-// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, !dbg ![[DI2:[0-9]+]]
-// CHECK: call void @__sanitizer_dtor_callback_vptr({{.*}}, !dbg ![[DI2]]
+// CHECK: call void @__sanitizer_dtor_callback_fields{{.*}}, !dbg ![[DI2:[0-9]+]]
+// CHECK: call void @__sanitizer_dtor_callback_vptr{{.*}}, !dbg ![[DI3:[0-9]+]]
 // CHECK: ret void
 
 // Poison members
 // CHECK-LABEL: define {{.*}}BD2Ev
-// CHECK: call void @__sanitizer_dtor_callback_fields({{.*}}, !dbg ![[DI4:[0-9]+]]
+// CHECK: call void @__sanitizer_dtor_callback_fields{{.*}}, !dbg ![[DI4:[0-9]+]]
 // CHECK: ret void
 
-// CHECK-LABEL: !DIFile{{.*}}cpp
+// CHECK-LABEL: !DIFile{{.*}}sanitize-dtor-vtable.cpp
 
 // CHECK-DAG: ![[DI1]] = {{.*}}line: [[@LINE-28]]
-// CHECK-DAG: ![[DI2]] = {{.*}}line: [[@LINE-37]]
-// CHECK-DAG: ![[DI4]] = {{.*}}line: [[@LINE-30]]
+// CHECK-DAG: ![[DI2]] = {{.*}}line: [[@LINE-39]]
+// CHECK-DAG: ![[DI3]] = {{.*}}line: [[@LINE-38]]
+// CHECK-DAG: ![[DI4]] = {{.*}}line: [[@LINE-33]]

compiler-rt/test/msan/dtor-base-access.cpp

int main() {
   assert(__msan_test_shadow(&g->tb0, sizeof(g->tb0)) == 0);
   assert(__msan_test_shadow(&g->b, sizeof(g->b)) == 0);
   assert(__msan_test_shadow(&g->tb1, sizeof(g->tb1)) == 0);
   assert(__msan_test_shadow(&g->d, sizeof(g->d)) == 0);
 
   __msan_print_shadow(&g->tb0, sizeof(g->tb0));
   // CHECK: Member fields were destroyed
   // CHECK: {{#0 0x.* in __sanitizer_dtor_callback}}
-  // CHECK: {{#1 0x.* in .*~Derived.*cpp:}}[[@LINE-20]]:
+  // CHECK: {{#1 0x.* in .*~Derived.*cpp:}}[[@LINE-56]]:
+  // CHECK: {{#2 0x.* in .*~Derived.*cpp:}}[[@LINE-21]]:
 
   __msan_print_shadow(&g->b, sizeof(g->b));
   // CHECK: Member fields were destroyed
   // CHECK: {{#0 0x.* in __sanitizer_dtor_callback}}
-  // CHECK: {{#1 0x.* in .*~Base.*cpp:}}[[@LINE-33]]:
+  // CHECK: {{#1 0x.* in .*~Base.*cpp:}}[[@LINE-67]]:
+  // CHECK: {{#2 0x.* in .*~Base.*cpp:}}[[@LINE-35]]:
 
   __msan_print_shadow(&g->tb1, sizeof(g->tb1));
   // CHECK: Member fields were destroyed
   // CHECK: {{#0 0x.* in __sanitizer_dtor_callback}}
-  // CHECK: {{#1 0x.* in .*~Derived.*cpp:}}[[@LINE-30]]:
+  // CHECK: {{#1 0x.* in .*~Derived.*cpp:}}[[@LINE-62]]:
+  // CHECK: {{#2 0x.* in .*~Derived.*cpp:}}[[@LINE-33]]:
 
   return 0;
 }

compiler-rt/test/msan/use-after-dtor.cpp

int main() {
   fprintf(stderr, "\n");  // Need output to parse for CHECK-UAD-OFF case
   return s->x_;
 
   // CHECK-UAD: WARNING: MemorySanitizer: use-of-uninitialized-value
   // CHECK-UAD: {{#0 0x.* in main.*use-after-dtor.cpp:}}[[@LINE-3]]
 
   // CHECK-ORIGINS: Member fields were destroyed
   // CHECK-ORIGINS: {{#0 0x.* in __sanitizer_dtor_callback}}
-  // CHECK-ORIGINS: {{#1 0x.* in .*~Simple.*cpp:}}[[@LINE-18]]:
+  // CHECK-ORIGINS: {{#1 0x.* in .*~Simple.*cpp:}}[[@LINE-24]]:
+  // CHECK-ORIGINS: {{#2 0x.* in .*~Simple.*cpp:}}[[@LINE-19]]:
 
   // CHECK-UAD: SUMMARY: MemorySanitizer: use-of-uninitialized-value {{.*main}}
   // CHECK-UAD-OFF-NOT: SUMMARY: MemorySanitizer: use-of-uninitialized-value
 }