Index: clang/lib/CodeGen/CGDebugInfo.cpp =================================================================== --- clang/lib/CodeGen/CGDebugInfo.cpp +++ clang/lib/CodeGen/CGDebugInfo.cpp @@ -1142,10 +1142,11 @@ // declared. SourceLocation Loc = Ty->getDecl()->getLocation(); + uint32_t Align = getDeclAlignIfRequired(Ty->getDecl(), CGM.getContext()); // Typedefs are derived from some other type. return DBuilder.createTypedef(Underlying, Ty->getDecl()->getName(), getOrCreateFile(Loc), getLineNumber(Loc), - getDeclContextDescriptor(Ty->getDecl())); + getDeclContextDescriptor(Ty->getDecl()), Align); } static unsigned getDwarfCC(CallingConv CC) { Index: clang/test/CodeGenCXX/debug-info-template-align.cpp =================================================================== --- /dev/null +++ clang/test/CodeGenCXX/debug-info-template-align.cpp @@ -0,0 +1,14 @@ +// Test for debug info related to DW_AT_alignment attribute in the typedef operator +// Supported: -O0, standalone DI +// RUN: %clang_cc1 -dwarf-version=5 -emit-llvm -triple x86_64-linux-gnu %s -o - \ +// RUN: -O0 -disable-llvm-passes \ +// RUN: -debug-info-kind=standalone \ +// RUN: | FileCheck %s + +// CHECK: DIDerivedType(tag: DW_TAG_typedef, {{.*}}, align: + +typedef char __attribute__((__aligned__(64))) alchar; + +int main() { + alchar newChar; +} Index: llvm/include/llvm/IR/DIBuilder.h =================================================================== --- llvm/include/llvm/IR/DIBuilder.h +++ llvm/include/llvm/IR/DIBuilder.h @@ -237,8 +237,10 @@ /// \param File File where this type is defined. /// \param LineNo Line number. /// \param Context The surrounding context for the typedef. + /// \param AlignInBits Alignment. (optional) DIDerivedType *createTypedef(DIType *Ty, StringRef Name, DIFile *File, - unsigned LineNo, DIScope *Context); + unsigned LineNo, DIScope *Context, + uint32_t AlignInBits = 0); /// Create debugging information entry for a 'friend'. DIDerivedType *createFriend(DIType *Ty, DIType *FriendTy); Index: llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp =================================================================== --- llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp +++ llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp @@ -800,6 +800,15 @@ if (!Name.empty()) addString(Buffer, dwarf::DW_AT_name, Name); + // If alignment is specified for a typedef , create and insert DW_AT_alignment + // attribute in DW_TAG_typedef DIE. + if (Tag == dwarf::DW_TAG_typedef && DD->getDwarfVersion() >= 5) { + uint32_t AlignInBytes = DTy->getAlignInBytes(); + if (AlignInBytes > 0) + addUInt(Buffer, dwarf::DW_AT_alignment, dwarf::DW_FORM_udata, + AlignInBytes); + } + // Add size if non-zero (derived types might be zero-sized.) if (Size && Tag != dwarf::DW_TAG_pointer_type && Tag != dwarf::DW_TAG_ptr_to_member_type Index: llvm/lib/IR/DIBuilder.cpp =================================================================== --- llvm/lib/IR/DIBuilder.cpp +++ llvm/lib/IR/DIBuilder.cpp @@ -305,10 +305,11 @@ DIDerivedType *DIBuilder::createTypedef(DIType *Ty, StringRef Name, DIFile *File, unsigned LineNo, - DIScope *Context) { + DIScope *Context, + uint32_t AlignInBits) { return DIDerivedType::get(VMContext, dwarf::DW_TAG_typedef, Name, File, - LineNo, getNonCompileUnitScope(Context), Ty, 0, 0, - 0, None, DINode::FlagZero); + LineNo, getNonCompileUnitScope(Context), Ty, 0, + AlignInBits, 0, None, DINode::FlagZero); } DIDerivedType *DIBuilder::createFriend(DIType *Ty, DIType *FriendTy) { Index: llvm/test/DebugInfo/X86/debug-info-template-align.ll =================================================================== --- /dev/null +++ llvm/test/DebugInfo/X86/debug-info-template-align.ll @@ -0,0 +1,64 @@ +; RUN: llc < %s -filetype=obj -o %t +; RUN: llvm-dwarfdump -v %t | FileCheck %s + +; C++ source to regenerate: + +;typedef char __attribute__((__aligned__(64))) alchar; + +;int main(){ +; alchar newChar; +;} +; $ clang++ -O0 -g -gdwarf-5 debug-info-template-align.cpp -c + +; CHECK: .debug_abbrev contents: + +; CHECK: [5] DW_TAG_typedef DW_CHILDREN_no +; CHECK: DW_AT_alignment DW_FORM_udata + +; CHECK: .debug_info contents: + +;CHECK: DW_TAG_typedef [5] +;CHECK: DW_AT_name {{.*}} "alchar" +;CHECK-NEXT: DW_AT_alignment [DW_FORM_udata] (64) + + +; ModuleID = '/dir/test.cpp' +source_filename = "/dir/test.cpp" +target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +; Function Attrs: noinline norecurse nounwind optnone uwtable +define dso_local i32 @main() #0 !dbg !7 { +entry: + %newChar = alloca i8, align 64 + call void @llvm.dbg.declare(metadata i8* %newChar, metadata !12, metadata !DIExpression()), !dbg !15 + ret i32 0, !dbg !16 +} + +; Function Attrs: nounwind readnone speculatable willreturn +declare void @llvm.dbg.declare(metadata, metadata, metadata) #1 + +attributes #0 = { noinline norecurse nounwind optnone uwtable } +attributes #1 = { nounwind readnone speculatable willreturn } + +!llvm.dbg.cu = !{!0} +!llvm.module.flags = !{!3, !4, !5} +!llvm.ident = !{!6} + +!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang version 10.0.0 ", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: None) +!1 = !DIFile(filename: "/dir/test.cpp", directory: "/home/awpandey/tools/llvm/test/DebugInfo", checksumkind: CSK_MD5, checksum: "872e252efdfcb9480b4bfaf8437f58ab") +!2 = !{} +!3 = !{i32 2, !"Dwarf Version", i32 5} +!4 = !{i32 2, !"Debug Info Version", i32 3} +!5 = !{i32 1, !"wchar_size", i32 4} +!6 = !{!"clang version 10.0.0 "} +!7 = distinct !DISubprogram(name: "main", scope: !8, file: !8, line: 12, type: !9, scopeLine: 12, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2) +!8 = !DIFile(filename: "test.cpp", directory: "/dir", checksumkind: CSK_MD5, checksum: "872e252efdfcb9480b4bfaf8437f58ab") +!9 = !DISubroutineType(types: !10) +!10 = !{!11} +!11 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!12 = !DILocalVariable(name: "newChar", scope: !7, file: !8, line: 13, type: !13) +!13 = !DIDerivedType(tag: DW_TAG_typedef, name: "alchar", file: !8, line: 10, baseType: !14, align: 512) +!14 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char) +!15 = !DILocation(line: 13, column: 10, scope: !7) +!16 = !DILocation(line: 14, column: 1, scope: !7)