[clang][DebugInfo] Attach DISubprogram to additional call variants

clang/lib/CodeGen/CGCall.cpp

@@ -38,6 +38,7 @@
 #include "llvm/IR/Attributes.h"
 #include "llvm/IR/CallingConv.h"
 #include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DebugInfoMetadata.h"
 #include "llvm/IR/InlineAsm.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/Intrinsics.h"
@@ -6277,6 +6278,24 @@ RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo,
     pushDestroy(QualType::DK_nontrivial_c_struct, Ret.getAggregateAddress(),
                 RetTy);
 
+  // Generate function declaration DISuprogram in order to be used
+  // in debug info about call sites.
+  if (CGDebugInfo *DI = getDebugInfo()) {
+    // Ensure call site info would actually be emitted before collecting
+    // further callee info.
+    if (CalleeDecl && !CalleeDecl->hasAttr<NoDebugAttr>() &&
+        DI->getCallSiteRelatedAttrs() != llvm::DINode::FlagZero) {
+      CodeGenFunction CalleeCGF(CGM);
+      const GlobalDecl &CalleeGlobalDecl =
+          Callee.getAbstractInfo().getCalleeDecl();
+      CalleeCGF.CurGD = CalleeGlobalDecl;
+      FunctionArgList Args;
+      QualType ResTy = CalleeCGF.BuildFunctionArgList(CalleeGlobalDecl, Args);
+      DI->EmitFuncDeclForCallSite(
+          CI, DI->getFunctionType(CalleeDecl, ResTy, Args), CalleeGlobalDecl);
+    }
+  }
+
   return Ret;
 }
 

clang/lib/CodeGen/CGDebugInfo.cpp

@@ -4952,7 +4952,7 @@ void CGDebugInfo::EmitFunctionDecl(GlobalDecl GD, SourceLocation Loc,
 
 void CGDebugInfo::EmitFuncDeclForCallSite(llvm::CallBase *CallOrInvoke,
                                           QualType CalleeType,
-                                          const FunctionDecl *CalleeDecl) {
+                                          GlobalDecl CalleeGlobalDecl) {
   if (!CallOrInvoke)
     return;
   auto *Func = dyn_cast<llvm::Function>(CallOrInvoke->getCalledOperand());
@@ -4961,6 +4961,9 @@ void CGDebugInfo::EmitFuncDeclForCallSite(llvm::CallBase *CallOrInvoke,
   if (Func->getSubprogram())
     return;
 
+  const FunctionDecl *CalleeDecl =
+      cast<FunctionDecl>(CalleeGlobalDecl.getDecl());
+
   // Do not emit a declaration subprogram for a function with nodebug
   // attribute, or if call site info isn't required.
   if (CalleeDecl->hasAttr<NoDebugAttr>() ||
@@ -4971,7 +4974,8 @@ void CGDebugInfo::EmitFuncDeclForCallSite(llvm::CallBase *CallOrInvoke,
   // create the one describing the function in order to have complete
   // call site debug info.
   if (!CalleeDecl->isStatic() && !CalleeDecl->isInlined())
-    EmitFunctionDecl(CalleeDecl, CalleeDecl->getLocation(), CalleeType, Func);
+    EmitFunctionDecl(CalleeGlobalDecl, CalleeDecl->getLocation(), CalleeType,
+                     Func);
 }
 
 void CGDebugInfo::EmitInlineFunctionStart(CGBuilderTy &Builder, GlobalDecl GD) {

clang/lib/CodeGen/CGDebugInfo.h

@@ -511,7 +511,7 @@ class CGDebugInfo {
   /// This is needed for call site debug info.
   void EmitFuncDeclForCallSite(llvm::CallBase *CallOrInvoke,
                                QualType CalleeType,
-                               const FunctionDecl *CalleeDecl);
+                               GlobalDecl CalleeGlobalDecl);
 
   /// Constructs the debug code for exiting a function.
   void EmitFunctionEnd(CGBuilderTy &Builder, llvm::Function *Fn);
@@ -678,6 +678,10 @@ class CGDebugInfo {
   /// Emit symbol for debugger that holds the pointer to the vtable.
   void emitVTableSymbol(llvm::GlobalVariable *VTable, const CXXRecordDecl *RD);
 
+  /// Return flags which enable debug info emission for call sites, provided
+  /// that it is supported and enabled.
+  llvm::DINode::DIFlags getCallSiteRelatedAttrs() const;
+
 private:
   /// Amend \p I's DebugLoc with \p Group (its source atom group) and \p
   /// Rank (lower nonzero rank is higher precedence). Does nothing if \p I
@@ -827,11 +831,6 @@ class CGDebugInfo {
                          unsigned LineNo, StringRef LinkageName,
                          llvm::GlobalVariable *Var, llvm::DIScope *DContext);
 
-
-  /// Return flags which enable debug info emission for call sites, provided
-  /// that it is supported and enabled.
-  llvm::DINode::DIFlags getCallSiteRelatedAttrs() const;
-
   /// Get the printing policy for producing names for debug info.
   PrintingPolicy getPrintingPolicy() const;
 

clang/lib/CodeGen/CGExpr.cpp

@@ -6632,15 +6632,6 @@ RValue CodeGenFunction::EmitCall(QualType CalleeType,
                          E == MustTailCall, E->getExprLoc());
 
   if (auto *CalleeDecl = dyn_cast_or_null<FunctionDecl>(TargetDecl)) {
-    // Generate function declaration DISuprogram in order to be used
-    // in debug info about call sites.
-    if (CGDebugInfo *DI = getDebugInfo()) {
-      FunctionArgList Args;
-      QualType ResTy = BuildFunctionArgList(CalleeDecl, Args);
-      DI->EmitFuncDeclForCallSite(LocalCallOrInvoke,
-                                  DI->getFunctionType(CalleeDecl, ResTy, Args),
-                                  CalleeDecl);
-    }
     if (CalleeDecl->hasAttr<RestrictAttr>() ||
         CalleeDecl->hasAttr<AllocSizeAttr>()) {
       // Function has 'malloc' (aka. 'restrict') or 'alloc_size' attribute.

clang/test/DebugInfo/CXX/decl-member-call.cpp

@@ -0,0 +1,25 @@
+// RUN: %clang_cc1 -O1 -triple x86_64-unknown_unknown -emit-llvm \
+// RUN:   -debug-info-kind=standalone -dwarf-version=5 %s -o - | FileCheck %s
+
+// Ensure both nonmember and member calls to declared function
+// have attached `DISubprogram`s.
+
+int nonmember(int n);
+
+struct S {
+  int x;
+  int member(int n);
+};
+
+int main(int argc, char** argv) {
+  struct S s = {};
+  int a = s.member(argc);
+  int b = nonmember(argc);
+  return a + b;
+}
+
+// CHECK: declare !dbg ![[SP1:[0-9]+]] noundef i32 @_ZN1S6memberEi(
+// CHECK: declare !dbg ![[SP2:[0-9]+]] noundef i32 @_Z9nonmemberi(
+
+// CHECK: ![[SP1]] = !DISubprogram(name: "member", linkageName: "_ZN1S6memberEi"
+// CHECK: ![[SP2]] = !DISubprogram(name: "nonmember", linkageName: "_Z9nonmemberi"