From: Amy Huang Date: Thu, 16 May 2019 22:28:52 +0000 (+0000) Subject: Emit global variables as S_CONSTANT records for codeview debug info. X-Git-Tag: android-x86-9.0-r1~3319 X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=1e2ceea64d3a371cef851f8e15dfea21733440b2;p=android-x86%2Fexternal-llvm.git Emit global variables as S_CONSTANT records for codeview debug info. Summary: This emits S_CONSTANT records for global variables. Currently this emits records for the global variables already being tracked in the LLVM IR metadata, which are just constant global variables; we'll also want S_CONSTANTs for static data members and enums. Related to https://bugs.llvm.org/show_bug.cgi?id=41615 Reviewers: rnk Subscribers: aprantl, hiraditya, llvm-commits, thakis Tags: #llvm Differential Revision: https://reviews.llvm.org/D61926 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360948 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp index c80c0314009..417388e8678 100644 --- a/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp +++ b/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp @@ -41,6 +41,7 @@ #include "llvm/Config/llvm-config.h" #include "llvm/DebugInfo/CodeView/CVTypeVisitor.h" #include "llvm/DebugInfo/CodeView/CodeView.h" +#include "llvm/DebugInfo/CodeView/CodeViewRecordIO.h" #include "llvm/DebugInfo/CodeView/ContinuationRecordBuilder.h" #include "llvm/DebugInfo/CodeView/DebugInlineeLinesSubsection.h" #include "llvm/DebugInfo/CodeView/EnumTables.h" @@ -66,6 +67,7 @@ #include "llvm/MC/MCSymbol.h" #include "llvm/Support/BinaryByteStream.h" #include "llvm/Support/BinaryStreamReader.h" +#include "llvm/Support/BinaryStreamWriter.h" #include "llvm/Support/Casting.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/Compiler.h" @@ -2940,10 +2942,19 @@ void CodeViewDebug::collectGlobalVariableInfo() { for (const MDNode *Node : CUs->operands()) { const auto *CU = cast(Node); for (const auto *GVE : CU->getGlobalVariables()) { + const DIGlobalVariable *DIGV = GVE->getVariable(); + const DIExpression *DIE = GVE->getExpression(); + + // Emit constant global variables in a global symbol section. + if (GlobalMap.count(GVE) == 0 && DIE->isConstant()) { + CVGlobalVariable CVGV = {DIGV, DIE}; + GlobalVariables.emplace_back(std::move(CVGV)); + } + const auto *GV = GlobalMap.lookup(GVE); if (!GV || GV->isDeclarationForLinker()) continue; - const DIGlobalVariable *DIGV = GVE->getVariable(); + DIScope *Scope = DIGV->getScope(); SmallVector *VariableList; if (Scope && isa(Scope)) { @@ -2958,7 +2969,7 @@ void CodeViewDebug::collectGlobalVariableInfo() { // Emit this global variable into a COMDAT section. VariableList = &ComdatVariables; else - // Emit this globla variable in a single global symbol section. + // Emit this global variable in a single global symbol section. VariableList = &GlobalVariables; CVGlobalVariable CVGV = {DIGV, GV}; VariableList->emplace_back(std::move(CVGV)); @@ -2981,13 +2992,14 @@ void CodeViewDebug::emitDebugInfoForGlobals() { // Second, emit each global that is in a comdat into its own .debug$S // section along with its own symbol substream. for (const CVGlobalVariable &CVGV : ComdatVariables) { - MCSymbol *GVSym = Asm->getSymbol(CVGV.GV); + const GlobalVariable *GV = CVGV.GVInfo.get(); + MCSymbol *GVSym = Asm->getSymbol(GV); OS.AddComment("Symbol subsection for " + - Twine(GlobalValue::dropLLVMManglingEscape(CVGV.GV->getName()))); + Twine(GlobalValue::dropLLVMManglingEscape(GV->getName()))); switchToDebugSectionForSymbol(GVSym); MCSymbol *EndLabel = beginCVSubsection(DebugSubsectionKind::Symbols); // FIXME: emitDebugInfoForGlobal() doesn't handle DIExpressions. - emitDebugInfoForGlobal(CVGV.DIGV, CVGV.GV, GVSym); + emitDebugInfoForGlobal(CVGV); endCVSubsection(EndLabel); } } @@ -3007,31 +3019,57 @@ void CodeViewDebug::emitDebugInfoForRetainedTypes() { // Emit each global variable in the specified array. void CodeViewDebug::emitGlobalVariableList(ArrayRef Globals) { for (const CVGlobalVariable &CVGV : Globals) { - MCSymbol *GVSym = Asm->getSymbol(CVGV.GV); // FIXME: emitDebugInfoForGlobal() doesn't handle DIExpressions. - emitDebugInfoForGlobal(CVGV.DIGV, CVGV.GV, GVSym); - } -} - -void CodeViewDebug::emitDebugInfoForGlobal(const DIGlobalVariable *DIGV, - const GlobalVariable *GV, - MCSymbol *GVSym) { - // DataSym record, see SymbolRecord.h for more info. Thread local data - // happens to have the same format as global data. - SymbolKind DataSym = GV->isThreadLocal() - ? (DIGV->isLocalToUnit() ? SymbolKind::S_LTHREAD32 - : SymbolKind::S_GTHREAD32) - : (DIGV->isLocalToUnit() ? SymbolKind::S_LDATA32 - : SymbolKind::S_GDATA32); - MCSymbol *DataEnd = beginSymbolRecord(DataSym); - OS.AddComment("Type"); - OS.EmitIntValue(getCompleteTypeIndex(DIGV->getType()).getIndex(), 4); - OS.AddComment("DataOffset"); - OS.EmitCOFFSecRel32(GVSym, /*Offset=*/0); - OS.AddComment("Segment"); - OS.EmitCOFFSectionIndex(GVSym); - OS.AddComment("Name"); - const unsigned LengthOfDataRecord = 12; - emitNullTerminatedSymbolName(OS, DIGV->getName(), LengthOfDataRecord); - endSymbolRecord(DataEnd); + emitDebugInfoForGlobal(CVGV); + } +} + +void CodeViewDebug::emitDebugInfoForGlobal(const CVGlobalVariable &CVGV) { + const DIGlobalVariable *DIGV = CVGV.DIGV; + if (const GlobalVariable *GV = + CVGV.GVInfo.dyn_cast()) { + // DataSym record, see SymbolRecord.h for more info. Thread local data + // happens to have the same format as global data. + MCSymbol *GVSym = Asm->getSymbol(GV); + SymbolKind DataSym = GV->isThreadLocal() + ? (DIGV->isLocalToUnit() ? SymbolKind::S_LTHREAD32 + : SymbolKind::S_GTHREAD32) + : (DIGV->isLocalToUnit() ? SymbolKind::S_LDATA32 + : SymbolKind::S_GDATA32); + MCSymbol *DataEnd = beginSymbolRecord(DataSym); + OS.AddComment("Type"); + OS.EmitIntValue(getCompleteTypeIndex(DIGV->getType()).getIndex(), 4); + OS.AddComment("DataOffset"); + OS.EmitCOFFSecRel32(GVSym, /*Offset=*/0); + OS.AddComment("Segment"); + OS.EmitCOFFSectionIndex(GVSym); + OS.AddComment("Name"); + const unsigned LengthOfDataRecord = 12; + emitNullTerminatedSymbolName(OS, DIGV->getName(), LengthOfDataRecord); + endSymbolRecord(DataEnd); + } else { + // FIXME: Currently this only emits the global variables in the IR metadata. + // This should also emit enums and static data members. + const DIExpression *DIE = CVGV.GVInfo.get(); + assert(DIE->isConstant() && + "Global constant variables must contain a constant expression."); + uint64_t Val = DIE->getElement(1); + + MCSymbol *SConstantEnd = beginSymbolRecord(SymbolKind::S_CONSTANT); + OS.AddComment("Type"); + OS.EmitIntValue(getTypeIndex(DIGV->getType()).getIndex(), 4); + OS.AddComment("Value"); + + // Encoded integers shouldn't need more than 10 bytes. + uint8_t data[10]; + BinaryStreamWriter Writer(data, llvm::support::endianness::little); + CodeViewRecordIO IO(Writer); + cantFail(IO.mapEncodedInteger(Val)); + StringRef SRef((char *)data, Writer.getOffset()); + OS.EmitBinaryData(SRef); + + OS.AddComment("Name"); + emitNullTerminatedSymbolName(OS, DIGV->getDisplayName()); + endSymbolRecord(SConstantEnd); + } } diff --git a/lib/CodeGen/AsmPrinter/CodeViewDebug.h b/lib/CodeGen/AsmPrinter/CodeViewDebug.h index f190b4a2b95..ce57b789d7f 100644 --- a/lib/CodeGen/AsmPrinter/CodeViewDebug.h +++ b/lib/CodeGen/AsmPrinter/CodeViewDebug.h @@ -17,6 +17,7 @@ #include "llvm/ADT/DenseMap.h" #include "llvm/ADT/DenseSet.h" #include "llvm/ADT/MapVector.h" +#include "llvm/ADT/PointerUnion.h" #include "llvm/ADT/SetVector.h" #include "llvm/ADT/SmallVector.h" #include "llvm/CodeGen/DbgEntityHistoryCalculator.h" @@ -100,7 +101,7 @@ class LLVM_LIBRARY_VISIBILITY CodeViewDebug : public DebugHandlerBase { struct CVGlobalVariable { const DIGlobalVariable *DIGV; - const GlobalVariable *GV; + PointerUnion GVInfo; }; struct InlineSite { @@ -313,8 +314,7 @@ class LLVM_LIBRARY_VISIBILITY CodeViewDebug : public DebugHandlerBase { void emitDebugInfoForGlobals(); void emitGlobalVariableList(ArrayRef Globals); - void emitDebugInfoForGlobal(const DIGlobalVariable *DIGV, - const GlobalVariable *GV, MCSymbol *GVSym); + void emitDebugInfoForGlobal(const CVGlobalVariable &CVGV); /// Opens a subsection of the given kind in a .debug$S codeview section. /// Returns an end label for use with endCVSubsection when the subsection is diff --git a/test/DebugInfo/COFF/global-constants.ll b/test/DebugInfo/COFF/global-constants.ll new file mode 100644 index 00000000000..b906886d0fd --- /dev/null +++ b/test/DebugInfo/COFF/global-constants.ll @@ -0,0 +1,64 @@ +; RUN: llc < %s | FileCheck %s --check-prefix=ASM +; RUN: llc < %s -filetype=obj | llvm-readobj - --codeview | FileCheck %s --check-prefix=OBJ + +; C++ source to regenerate: +; const int Test1 = 1; +; int main() { +; return Test1; +; } +; $ clang t.cpp -S -emit-llvm -g -gcodeview -o t.ll + +; ASM-LABEL: .long 241 # Symbol subsection for globals + +; ASM: .short {{.*-.*}} # Record length +; ASM: .short 4359 # Record kind: S_CONSTANT +; ASM-NEXT: .long 4099 # Type +; ASM-NEXT: .byte 0x01, 0x00 # Value +; ASM-NEXT: .asciz "Test1" # Name + +; OBJ: CodeViewDebugInfo [ +; OBJ: Section: .debug$S +; OBJ: Magic: 0x4 +; OBJ: Subsection [ +; OBJ: SubSectionType: Symbols (0xF1) +; OBJ: ConstantSym { +; OBJ-NEXT: Kind: S_CONSTANT (0x1107) +; OBJ-NEXT: Type: const int (0x1003) +; OBJ-NEXT: Value: 1 +; OBJ-NEXT: Name: Test1 +; OBJ-NEXT: } + +; ModuleID = 't.cpp' +source_filename = "t.cpp" +target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-pc-windows-msvc" + +; Function Attrs: noinline norecurse nounwind optnone +define dso_local i32 @main() #0 !dbg !13 { +entry: + %retval = alloca i32, align 4 + store i32 0, i32* %retval, align 4 + ret i32 1, !dbg !16 +} + +!llvm.dbg.cu = !{!0} +!llvm.module.flags = !{!9, !10, !11} +!llvm.ident = !{!12} + +!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 9.0.0 (https://github.com/llvm/llvm-project.git 4a1902b6739e3087a03c0ac7ab85b640764e9335)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, globals: !3, nameTableKind: None) +!1 = !DIFile(filename: "", directory: "C:\5Csrc\5Ctest", checksumkind: CSK_MD5, checksum: "0d5ef00bdd80bdb409a3deac9938f20d") +!2 = !{} +!3 = !{!4} +!4 = !DIGlobalVariableExpression(var: !5, expr: !DIExpression(DW_OP_constu, 1, DW_OP_stack_value)) +!5 = distinct !DIGlobalVariable(name: "Test1", scope: !0, file: !6, line: 1, type: !7, isLocal: true, isDefinition: true) +!6 = !DIFile(filename: "t.cpp", directory: "C:\5Csrc\5Ctest", checksumkind: CSK_MD5, checksum: "0d5ef00bdd80bdb409a3deac9938f20d") +!7 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !8) +!8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!9 = !{i32 2, !"CodeView", i32 1} +!10 = !{i32 2, !"Debug Info Version", i32 3} +!11 = !{i32 1, !"wchar_size", i32 2} +!12 = !{!"clang version 9.0.0 (https://github.com/llvm/llvm-project.git 4a1902b6739e3087a03c0ac7ab85b640764e9335)"} +!13 = distinct !DISubprogram(name: "main", scope: !6, file: !6, line: 3, type: !14, scopeLine: 3, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2) +!14 = !DISubroutineType(types: !15) +!15 = !{!8} +!16 = !DILocation(line: 4, scope: !13)