https://github.com/jryans created https://github.com/llvm/llvm-project/pull/166202
`DISubprogram`s are attached to call sites to support various debug info features, including entry values and tail calls. Clang 9.0 (0f6516856670a435461f56a9faeb4aa8a35a6679) was the first version to include this kind of call site `DISubprogram` attachment. This earlier work appears to visit only some call site variants, however. The call site attachment was added to a higher-level `EmitCall` path in Clang's code gen that is only used by some call variants. In particular, some C++ member calls use a different code gen path, which did not include this call site attachment step, and thus the debug info it triggers (e.g. call site entries) was not emitted for such calls. This moves `DISubprogram` attachment to a lower-level call emission path that is used by all call variants. Fixes https://github.com/llvm/llvm-project/issues/161962 >From 919d777096d5a75383976a8613088abcc45efe42 Mon Sep 17 00:00:00 2001 From: "J. Ryan Stinnett" <[email protected]> Date: Fri, 31 Oct 2025 14:45:07 +0000 Subject: [PATCH] [clang][DebugInfo] Attach `DISubprogram` to additional call variants `DISubprogram`s are attached to call sites to support various debug info features, including entry values and tail calls. Clang 9.0 (0f6516856670a435461f56a9faeb4aa8a35a6679) was the first version to include this kind of call site `DISubprogram` attachment. This earlier work appears to visit only some call site variants, however. The call site attachment was added to a higher-level `EmitCall` path in Clang's code gen that is only used by some call variants. In particular, some C++ member calls use a different code gen path, which did not include this call site attachment step, and thus the debug info it triggers (e.g. call site entries) was not emitted for such calls. This moves `DISubprogram` attachment to a lower-level call emission path that is used by all call variants. Fixes https://github.com/llvm/llvm-project/issues/161962 --- clang/lib/CodeGen/CGCall.cpp | 15 +++++++++++ clang/lib/CodeGen/CGDebugInfo.cpp | 8 ++++-- clang/lib/CodeGen/CGDebugInfo.h | 2 +- clang/lib/CodeGen/CGExpr.cpp | 9 ------- clang/test/DebugInfo/CXX/decl-member-call.cpp | 25 +++++++++++++++++++ 5 files changed, 47 insertions(+), 12 deletions(-) create mode 100644 clang/test/DebugInfo/CXX/decl-member-call.cpp diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp index 465f3f4e670c2..2e4ffd42b915c 100644 --- a/clang/lib/CodeGen/CGCall.cpp +++ b/clang/lib/CodeGen/CGCall.cpp @@ -6277,6 +6277,21 @@ RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo, pushDestroy(QualType::DK_nontrivial_c_struct, Ret.getAggregateAddress(), RetTy); + if (CalleeDecl) { + // Generate function declaration DISuprogram in order to be used + // in debug info about call sites. + if (CGDebugInfo *DI = getDebugInfo()) { + 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; } diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp index 07a2cfb21bef2..67675dae71c34 100644 --- a/clang/lib/CodeGen/CGDebugInfo.cpp +++ b/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) { diff --git a/clang/lib/CodeGen/CGDebugInfo.h b/clang/lib/CodeGen/CGDebugInfo.h index 78c3eb9c5792e..1f695941f113a 100644 --- a/clang/lib/CodeGen/CGDebugInfo.h +++ b/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); diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp index 01f2161f27555..a837f00732748 100644 --- a/clang/lib/CodeGen/CGExpr.cpp +++ b/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. diff --git a/clang/test/DebugInfo/CXX/decl-member-call.cpp b/clang/test/DebugInfo/CXX/decl-member-call.cpp new file mode 100644 index 0000000000000..95758a2985c0c --- /dev/null +++ b/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" _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
