[llvm] r360948 - Emit global variables as S_CONSTANT records for codeview debug info.
Amy Huang via llvm-commits
llvm-commits at lists.llvm.org
Thu May 16 15:28:52 PDT 2019
Author: akhuang
Date: Thu May 16 15:28:52 2019
New Revision: 360948
URL: http://llvm.org/viewvc/llvm-project?rev=360948&view=rev
Log:
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
Added:
llvm/trunk/test/DebugInfo/COFF/global-constants.ll
Modified:
llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.h
Modified: llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp?rev=360948&r1=360947&r2=360948&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp Thu May 16 15:28:52 2019
@@ -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::collectGlobalVariabl
for (const MDNode *Node : CUs->operands()) {
const auto *CU = cast<DICompileUnit>(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<CVGlobalVariable, 1> *VariableList;
if (Scope && isa<DILocalScope>(Scope)) {
@@ -2958,7 +2969,7 @@ void CodeViewDebug::collectGlobalVariabl
// 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::emitDebugInfoForGlob
// 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<const GlobalVariable *>();
+ 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::emitDebugInfoForReta
// Emit each global variable in the specified array.
void CodeViewDebug::emitGlobalVariableList(ArrayRef<CVGlobalVariable> Globals) {
for (const CVGlobalVariable &CVGV : Globals) {
- MCSymbol *GVSym = Asm->getSymbol(CVGV.GV);
// FIXME: emitDebugInfoForGlobal() doesn't handle DIExpressions.
- emitDebugInfoForGlobal(CVGV.DIGV, CVGV.GV, GVSym);
+ emitDebugInfoForGlobal(CVGV);
}
}
-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);
+void CodeViewDebug::emitDebugInfoForGlobal(const CVGlobalVariable &CVGV) {
+ const DIGlobalVariable *DIGV = CVGV.DIGV;
+ if (const GlobalVariable *GV =
+ CVGV.GVInfo.dyn_cast<const GlobalVariable *>()) {
+ // 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<const DIExpression *>();
+ 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);
+ }
}
Modified: llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.h?rev=360948&r1=360947&r2=360948&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.h (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/CodeViewDebug.h Thu May 16 15:28:52 2019
@@ -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 CodeViewDe
struct CVGlobalVariable {
const DIGlobalVariable *DIGV;
- const GlobalVariable *GV;
+ PointerUnion<const GlobalVariable *, const DIExpression *> GVInfo;
};
struct InlineSite {
@@ -313,8 +314,7 @@ class LLVM_LIBRARY_VISIBILITY CodeViewDe
void emitDebugInfoForGlobals();
void emitGlobalVariableList(ArrayRef<CVGlobalVariable> 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
Added: llvm/trunk/test/DebugInfo/COFF/global-constants.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/COFF/global-constants.ll?rev=360948&view=auto
==============================================================================
--- llvm/trunk/test/DebugInfo/COFF/global-constants.ll (added)
+++ llvm/trunk/test/DebugInfo/COFF/global-constants.ll Thu May 16 15:28:52 2019
@@ -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: "<stdin>", 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)
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