diff --git a/clang/lib/CodeGen/CGDebugInfo.h b/clang/lib/CodeGen/CGDebugInfo.h --- a/clang/lib/CodeGen/CGDebugInfo.h +++ b/clang/lib/CodeGen/CGDebugInfo.h @@ -533,6 +533,10 @@ /// Emit an @import declaration. void EmitImportDecl(const ImportDecl &ID); + /// Create and attach debuginfo to a the provided string literal GV. + void AddStringLiteralDebugInfo(llvm::GlobalVariable *GV, StringRef Name, + const StringLiteral *S); + /// Emit C++ namespace alias. llvm::DIImportedEntity *EmitNamespaceAlias(const NamespaceAliasDecl &NA); diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp --- a/clang/lib/CodeGen/CGDebugInfo.cpp +++ b/clang/lib/CodeGen/CGDebugInfo.cpp @@ -5131,7 +5131,7 @@ return Name; codegenoptions::DebugTemplateNamesKind TemplateNamesKind = CGM.getCodeGenOpts().getDebugSimpleTemplateNames(); - + if (!CGM.getCodeGenOpts().hasReducedDebugInfo()) TemplateNamesKind = codegenoptions::DebugTemplateNamesKind::Full; @@ -5458,6 +5458,22 @@ ImportedDeclCache[GD.getCanonicalDecl().getDecl()].reset(ImportDI); } +void CGDebugInfo::AddStringLiteralDebugInfo(llvm::GlobalVariable *GV, + StringRef Name, + const StringLiteral *S) { + SourceLocation Loc = S->getStrTokenLoc(0); + PresumedLoc PLoc = CGM.getContext().getSourceManager().getPresumedLoc(Loc); + if (!PLoc.isValid()) + return; + + llvm::DIFile *File = getOrCreateFile(Loc); + llvm::DIGlobalVariableExpression *Debug = + DBuilder.createGlobalVariableExpression( + nullptr, StringRef(), StringRef(), getOrCreateFile(Loc), + getLineNumber(Loc), getOrCreateType(S->getType(), File), true); + GV->addDebugInfo(Debug); +} + llvm::DIScope *CGDebugInfo::getCurrentContextDescriptor(const Decl *D) { if (!LexicalBlockStack.empty()) return LexicalBlockStack.back(); diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp --- a/clang/lib/CodeGen/CodeGenModule.cpp +++ b/clang/lib/CodeGen/CodeGenModule.cpp @@ -5670,6 +5670,11 @@ } auto GV = GenerateStringLiteral(C, LT, *this, GlobalVariableName, Alignment); + + CGDebugInfo *DI = getModuleDebugInfo(); + if (DI && getCodeGenOpts().hasReducedDebugInfo()) + DI->AddStringLiteralDebugInfo(GV, GlobalVariableName, S); + if (Entry) *Entry = GV; diff --git a/clang/test/CodeGen/debug-info-variables.c b/clang/test/CodeGen/debug-info-variables.c new file mode 100644 --- /dev/null +++ b/clang/test/CodeGen/debug-info-variables.c @@ -0,0 +1,17 @@ +// RUN: %clang_cc1 %s -debug-info-kind=standalone -S -emit-llvm -o - | FileCheck %s + +// CHECK: DIGlobalVariable(name: "global" +int global = 42; + +// CHECK: DIGlobalVariable({{.*}}line: [[@LINE+2]] +const char* s() { + return "1234567890"; +} + +// CHECK: DILocalVariable(name: "p" +// CHECK: DILocalVariable(name: "q" +// CHECK: DILocalVariable(name: "r" +int sum(int p, int q) { + int r = p + q; + return r; +} diff --git a/clang/test/VFS/external-names.c b/clang/test/VFS/external-names.c --- a/clang/test/VFS/external-names.c +++ b/clang/test/VFS/external-names.c @@ -30,8 +30,8 @@ // Debug info // RUN: %clang_cc1 -I %t -ivfsoverlay %t.external.yaml -triple %itanium_abi_triple -debug-info-kind=limited -emit-llvm %s -o - | FileCheck -check-prefix=CHECK-DEBUG-EXTERNAL %s -// CHECK-DEBUG-EXTERNAL: !DISubprogram({{.*}}file: ![[Num:[0-9]+]] -// CHECK-DEBUG-EXTERNAL: ![[Num]] = !DIFile(filename: "{{[^"]*}}Inputs{{..?}}external-names.h" +// CHECK-DEBUG-EXTERNAL: ![[Num:[0-9]+]] = !DIFile(filename: "{{[^"]*}}Inputs{{..?}}external-names.h" +// CHECK-DEBUG-EXTERNAL: !DISubprogram({{.*}}file: ![[Num]] // RUN: %clang_cc1 -I %t -ivfsoverlay %t.yaml -triple %itanium_abi_triple -debug-info-kind=limited -emit-llvm %s -o - | FileCheck -check-prefix=CHECK-DEBUG %s // CHECK-DEBUG-NOT: Inputs diff --git a/llvm/lib/AsmParser/LLParser.cpp b/llvm/lib/AsmParser/LLParser.cpp --- a/llvm/lib/AsmParser/LLParser.cpp +++ b/llvm/lib/AsmParser/LLParser.cpp @@ -5010,7 +5010,7 @@ /// declaration: !4, align: 8) bool LLParser::parseDIGlobalVariable(MDNode *&Result, bool IsDistinct) { #define VISIT_MD_FIELDS(OPTIONAL, REQUIRED) \ - REQUIRED(name, MDStringField, (/* AllowEmpty */ false)); \ + OPTIONAL(name, MDStringField, (/* AllowEmpty */ false)); \ OPTIONAL(scope, MDField, ); \ OPTIONAL(linkageName, MDStringField, ); \ OPTIONAL(file, MDField, ); \ diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp --- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp @@ -3175,6 +3175,11 @@ for (const auto *GVE : CU->getGlobalVariables()) { const DIGlobalVariable *DIGV = GVE->getVariable(); const DIExpression *DIE = GVE->getExpression(); + // Don't emit string literals in CodeView, as the only useful parts are + // generally the filename and line number, which isn't possible to output + // in CodeView. String literals should be the only unnamed GlobalVariable + // with debug info. + if (DIGV->getName().empty()) continue; if ((DIE->getNumElements() == 2) && (DIE->getElement(0) == dwarf::DW_OP_plus_uconst)) diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp --- a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp @@ -165,7 +165,9 @@ } else { DeclContext = GV->getScope(); // Add name and type. - addString(*VariableDIE, dwarf::DW_AT_name, GV->getDisplayName()); + StringRef DisplayName = GV->getDisplayName(); + if (!DisplayName.empty()) + addString(*VariableDIE, dwarf::DW_AT_name, GV->getDisplayName()); if (GTy) addType(*VariableDIE, GTy); diff --git a/llvm/test/DebugInfo/COFF/global-no-strings.ll b/llvm/test/DebugInfo/COFF/global-no-strings.ll new file mode 100644 --- /dev/null +++ b/llvm/test/DebugInfo/COFF/global-no-strings.ll @@ -0,0 +1,59 @@ +; RUN: llc < %s | FileCheck %s +; RUN: llc < %s -filetype=obj | llvm-readobj - --codeview | FileCheck %s + +; This test ensures that no debuginfo is emitted for the constant "123456789" +; string. These global variables have debug expressions because DWARF has the +; ability to tie them to a file name and line number, but this isn't possible +; in CodeView, so we make sure it's omitted to save file size. +; +; The various CodeView outputs should have a description of "my_string", but not +; the string contents itself. + +; C++ source to regenerate: +; $ cat a.cpp +; char* my_string = +; "12345679"; +; +; $ clang-cl a.cpp /GS- /Z7 /GR- /clang:-S /clang:-emit-llvm + +; CHECK-NOT: S_LDATA +; CHECK: S_GDATA +; CHECK-NOT: S_LDATA +; CHECK-NOT: S_GDATA + +; ModuleID = '/tmp/a.c' +source_filename = "/tmp/a.c" +target datalayout = "e-m:w-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-pc-windows-msvc19.20.0" + +$"??_C@_08HCBFHPJA@12345679?$AA@" = comdat any + +@"??_C@_08HCBFHPJA@12345679?$AA@" = linkonce_odr dso_local unnamed_addr constant [9 x i8] c"12345679\00", comdat, align 1, !dbg !0 +@my_string = dso_local global ptr @"??_C@_08HCBFHPJA@12345679?$AA@", align 8, !dbg !7 + +!llvm.dbg.cu = !{!9} +!llvm.linker.options = !{!13, !14} +!llvm.module.flags = !{!15, !16, !17, !18, !19} +!llvm.ident = !{!20} + +!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression()) +!1 = distinct !DIGlobalVariable(scope: null, file: !2, line: 2, type: !3, isLocal: true, isDefinition: true) +!2 = !DIFile(filename: "/tmp/a.c", directory: "", checksumkind: CSK_MD5, checksum: "b972961d64de3c90497767110ab58eb6") +!3 = !DICompositeType(tag: DW_TAG_array_type, baseType: !4, size: 72, elements: !5) +!4 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char) +!5 = !{!6} +!6 = !DISubrange(count: 9) +!7 = !DIGlobalVariableExpression(var: !8, expr: !DIExpression()) +!8 = distinct !DIGlobalVariable(name: "my_string", scope: !9, file: !2, line: 1, type: !12, isLocal: false, isDefinition: true) +!9 = distinct !DICompileUnit(language: DW_LANG_C99, file: !10, producer: "clang version 15.0.0 (https://github.com/llvm/llvm-project.git 7c1c0849f8a1a6f1bf5f5b554484bbf8b0debd0a)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, globals: !11, splitDebugInlining: false, nameTableKind: None) +!10 = !DIFile(filename: "/tmp/a.c", directory: "/usr/local/google/home/mitchp/llvm-build/opt", checksumkind: CSK_MD5, checksum: "b972961d64de3c90497767110ab58eb6") +!11 = !{!0, !7} +!12 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !4, size: 64) +!13 = !{!"/DEFAULTLIB:libcmt.lib"} +!14 = !{!"/DEFAULTLIB:oldnames.lib"} +!15 = !{i32 2, !"CodeView", i32 1} +!16 = !{i32 2, !"Debug Info Version", i32 3} +!17 = !{i32 1, !"wchar_size", i32 2} +!18 = !{i32 7, !"PIC Level", i32 2} +!19 = !{i32 7, !"uwtable", i32 2} +!20 = !{!"clang version 15.0.0 (https://github.com/llvm/llvm-project.git 7c1c0849f8a1a6f1bf5f5b554484bbf8b0debd0a)"}