[llvm] r242302 - Debug Info: Add basic support for external types references.
Adrian Prantl
aprantl at apple.com
Wed Jul 15 10:01:42 PDT 2015
Author: adrian
Date: Wed Jul 15 12:01:41 2015
New Revision: 242302
URL: http://llvm.org/viewvc/llvm-project?rev=242302&view=rev
Log:
Debug Info: Add basic support for external types references.
This is a necessary prerequisite for bootstrapping the emission
of debug info inside modules.
- Adds a FlagExternalTypeRef to DICompositeType.
External types must have a unique identifier.
- External type references are emitted using a forward declaration
with a DW_AT_signature([DW_FORM_ref_sig8]) based on the UID.
http://reviews.llvm.org/D9612
Added:
llvm/trunk/test/DebugInfo/X86/externaltyperef.ll
Modified:
llvm/trunk/include/llvm/IR/DIBuilder.h
llvm/trunk/include/llvm/IR/DebugInfoFlags.def
llvm/trunk/include/llvm/IR/DebugInfoMetadata.h
llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.h
llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.h
llvm/trunk/lib/IR/DIBuilder.cpp
Modified: llvm/trunk/include/llvm/IR/DIBuilder.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/IR/DIBuilder.h?rev=242302&r1=242301&r2=242302&view=diff
==============================================================================
--- llvm/trunk/include/llvm/IR/DIBuilder.h (original)
+++ llvm/trunk/include/llvm/IR/DIBuilder.h Wed Jul 15 12:01:41 2015
@@ -384,6 +384,13 @@ namespace llvm {
DITypeRefArray ParameterTypes,
unsigned Flags = 0);
+ /// Create an external type reference.
+ /// \param Tag Dwarf TAG.
+ /// \param File File in which the type is defined.
+ /// \param UniqueIdentifier A unique identifier for the type.
+ DICompositeType *createExternalTypeRef(unsigned Tag, DIFile *File,
+ StringRef UniqueIdentifier);
+
/// Create a new DIType* with "artificial" flag set.
DIType *createArtificialType(DIType *Ty);
Modified: llvm/trunk/include/llvm/IR/DebugInfoFlags.def
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/IR/DebugInfoFlags.def?rev=242302&r1=242301&r2=242302&view=diff
==============================================================================
--- llvm/trunk/include/llvm/IR/DebugInfoFlags.def (original)
+++ llvm/trunk/include/llvm/IR/DebugInfoFlags.def Wed Jul 15 12:01:41 2015
@@ -32,5 +32,6 @@ HANDLE_DI_FLAG((1 << 11), Vector)
HANDLE_DI_FLAG((1 << 12), StaticMember)
HANDLE_DI_FLAG((1 << 13), LValueReference)
HANDLE_DI_FLAG((1 << 14), RValueReference)
+HANDLE_DI_FLAG((1 << 15), ExternalTypeRef)
#undef HANDLE_DI_FLAG
Modified: llvm/trunk/include/llvm/IR/DebugInfoMetadata.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/IR/DebugInfoMetadata.h?rev=242302&r1=242301&r2=242302&view=diff
==============================================================================
--- llvm/trunk/include/llvm/IR/DebugInfoMetadata.h (original)
+++ llvm/trunk/include/llvm/IR/DebugInfoMetadata.h Wed Jul 15 12:01:41 2015
@@ -574,6 +574,7 @@ public:
bool isStaticMember() const { return getFlags() & FlagStaticMember; }
bool isLValueReference() const { return getFlags() & FlagLValueReference; }
bool isRValueReference() const { return getFlags() & FlagRValueReference; }
+ bool isExternalTypeRef() const { return getFlags() & FlagExternalTypeRef; }
DITypeRef getRef() const { return DITypeRef::get(this); }
Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp?rev=242302&r1=242301&r2=242302&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp Wed Jul 15 12:01:41 2015
@@ -467,7 +467,10 @@ void DwarfDebug::beginModule() {
for (auto *Ty : CUNode->getRetainedTypes()) {
// The retained types array by design contains pointers to
// MDNodes rather than DIRefs. Unique them here.
- CU.getOrCreateTypeDIE(cast<DIType>(resolve(Ty->getRef())));
+ DIType *RT = cast<DIType>(resolve(Ty->getRef()));
+ if (!RT->isExternalTypeRef())
+ // There is no point in force-emitting a forward declaration.
+ CU.getOrCreateTypeDIE(RT);
}
// Emit imported_modules last so that the relevant context is already
// available.
@@ -1884,7 +1887,7 @@ MCDwarfDwoLineTable *DwarfDebug::getDwoL
return &SplitTypeUnitFileTable;
}
-static uint64_t makeTypeSignature(StringRef Identifier) {
+uint64_t DwarfDebug::makeTypeSignature(StringRef Identifier) {
MD5 Hash;
Hash.update(Identifier);
// ... take the least significant 8 bytes and return those. Our MD5
Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.h?rev=242302&r1=242301&r2=242302&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.h (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.h Wed Jul 15 12:01:41 2015
@@ -544,6 +544,9 @@ public:
/// Process end of an instruction.
void endInstruction() override;
+ /// Perform an MD5 checksum of \p Identifier and return the lower 64 bits.
+ static uint64_t makeTypeSignature(StringRef Identifier);
+
/// Add a DIE to the set of types that we're going to pull into
/// type units.
void addDwarfTypeUnitType(DwarfCompileUnit &CU, StringRef Identifier,
Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.cpp?rev=242302&r1=242301&r2=242302&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.cpp (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.cpp Wed Jul 15 12:01:41 2015
@@ -277,6 +277,13 @@ void DwarfUnit::addDIETypeSignature(DIE
dwarf::DW_FORM_ref_sig8, DIETypeSignature(Type));
}
+void DwarfUnit::addDIETypeSignature(DIE &Die, dwarf::Attribute Attribute,
+ StringRef Identifier) {
+ uint64_t Signature = DD->makeTypeSignature(Identifier);
+ Die.addValue(DIEValueAllocator, Attribute, dwarf::DW_FORM_ref_sig8,
+ DIEInteger(Signature));
+}
+
void DwarfUnit::addDIEEntry(DIE &Die, dwarf::Attribute Attribute,
DIEEntry Entry) {
const DIE *DieCU = Die.getUnitOrNull();
@@ -700,7 +707,8 @@ DIE *DwarfUnit::createTypeDIE(const DICo
constructTypeDIE(TyDIE, cast<DICompositeType>(Ty));
- updateAcceleratorTables(Context, Ty, TyDIE);
+ if (!Ty->isExternalTypeRef())
+ updateAcceleratorTables(Context, Ty, TyDIE);
return &TyDIE;
}
@@ -899,6 +907,13 @@ void DwarfUnit::constructTypeDIE(DIE &Bu
}
void DwarfUnit::constructTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
+ if (CTy->isExternalTypeRef()) {
+ StringRef Identifier = CTy->getIdentifier();
+ assert(!Identifier.empty() && "external type ref without identifier");
+ addFlag(Buffer, dwarf::DW_AT_declaration);
+ return addDIETypeSignature(Buffer, dwarf::DW_AT_signature, Identifier);
+ }
+
// Add name if not anonymous or intermediate type.
StringRef Name = CTy->getName();
Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.h?rev=242302&r1=242301&r2=242302&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.h (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.h Wed Jul 15 12:01:41 2015
@@ -228,7 +228,11 @@ public:
/// Add a DIE attribute data and value.
void addDIEEntry(DIE &Die, dwarf::Attribute Attribute, DIEEntry Entry);
+ /// Add a type's DW_AT_signature and set the declaration flag.
void addDIETypeSignature(DIE &Die, const DwarfTypeUnit &Type);
+ /// Add an attribute containing the type signature for a unique identifier.
+ void addDIETypeSignature(DIE &Die, dwarf::Attribute Attribute,
+ StringRef Identifier);
/// Add block data.
void addBlock(DIE &Die, dwarf::Attribute Attribute, DIELoc *Block);
Modified: llvm/trunk/lib/IR/DIBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/IR/DIBuilder.cpp?rev=242302&r1=242301&r2=242302&view=diff
==============================================================================
--- llvm/trunk/lib/IR/DIBuilder.cpp (original)
+++ llvm/trunk/lib/IR/DIBuilder.cpp Wed Jul 15 12:01:41 2015
@@ -435,6 +435,18 @@ DISubroutineType *DIBuilder::createSubro
return DISubroutineType::get(VMContext, Flags, ParameterTypes);
}
+DICompositeType *DIBuilder::createExternalTypeRef(unsigned Tag, DIFile *File,
+ StringRef UniqueIdentifier) {
+ assert(!UniqueIdentifier.empty() && "external type ref without uid");
+ auto *CTy =
+ DICompositeType::get(VMContext, Tag, "", nullptr, 0, nullptr, nullptr, 0,
+ 0, 0, DINode::FlagExternalTypeRef, nullptr, 0,
+ nullptr, nullptr, UniqueIdentifier);
+ // Types with unique IDs need to be in the type map.
+ retainType(CTy);
+ return CTy;
+}
+
DICompositeType *DIBuilder::createEnumerationType(
DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
uint64_t SizeInBits, uint64_t AlignInBits, DINodeArray Elements,
Added: llvm/trunk/test/DebugInfo/X86/externaltyperef.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/X86/externaltyperef.ll?rev=242302&view=auto
==============================================================================
--- llvm/trunk/test/DebugInfo/X86/externaltyperef.ll (added)
+++ llvm/trunk/test/DebugInfo/X86/externaltyperef.ll Wed Jul 15 12:01:41 2015
@@ -0,0 +1,51 @@
+; REQUIRES: object-emission
+; RUN: %llc_dwarf -filetype=obj -O0 < %s | llvm-dwarfdump -debug-dump=info - | FileCheck %s
+; Manually derived by externalizing the composite types from:
+;
+; namespace N { class B; }
+; using N::B;
+; class A;
+; A *a;
+;
+; Test the direct use of an external type.
+; CHECK: DW_TAG_variable
+; CHECK: DW_AT_type [DW_FORM_ref4] {{.*}}{[[PTR:.*]]}
+; CHECK: [[PTR]]: DW_TAG_pointer_type
+; CHECK: DW_AT_type [DW_FORM_ref4] {{.*}}{[[A:.*]]}
+; CHECK: [[A]]: DW_TAG_class_type
+; CHECK: DW_AT_declaration [DW_FORM_flag] (0x01)
+; CHECK: DW_AT_signature [DW_FORM_ref_sig8] (0x4e834ea939695c24)
+; CHECK: [[B:.*]]: DW_TAG_class_type
+; CHECK: DW_AT_declaration [DW_FORM_flag] (0x01)
+; CHECK: DW_AT_signature [DW_FORM_ref_sig8] (0x942e51c7addda5f7)
+; CHECK: DW_TAG_imported_declaration
+; CHECK: DW_AT_import [DW_FORM_ref4] {{.*}}[[B]]
+
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.10.0"
+
+%class.A = type opaque
+
+ at a = global %class.A* null, align 8
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!13, !14, !15}
+!llvm.ident = !{!16}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 3.7.0 (trunk 242039) (llvm/trunk 242046)", isOptimized: false, runtimeVersion: 0, emissionKind: 1, enums: !2, retainedTypes: !3, globals: !5, imports: !11)
+!1 = !DIFile(filename: "test.cpp", directory: "/")
+!2 = !{}
+!3 = !{!4, !9}
+!4 = !DICompositeType(tag: DW_TAG_class_type, name: "A", file: !1, flags: DIFlagExternalTypeRef, identifier: "_ZTS1A")
+!5 = !{!6}
+!6 = !DIGlobalVariable(name: "a", scope: !0, file: !1, line: 2, type: !7, isLocal: false, isDefinition: true, variable: %class.A** @a)
+!7 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !"_ZTS1A", size: 64, align: 64)
+!8 = !DICompositeType(tag: DW_TAG_class_type, name: "B", file: !1, flags: DIFlagExternalTypeRef, identifier: "_ZTS1B")
+!9 = !DICompositeType(tag: DW_TAG_class_type, name: "A", file: !1, flags: DIFlagExternalTypeRef, identifier: "_ZTSN1N1BE")
+!10 = !DINamespace(name: "N", scope: null, file: !1, line: 1)
+!11 = !{!12}
+!12 = !DIImportedEntity(tag: DW_TAG_imported_declaration, scope: !0, entity: !"_ZTSN1N1BE", line: 4)
+!13 = !{i32 2, !"Dwarf Version", i32 2}
+!14 = !{i32 2, !"Debug Info Version", i32 3}
+!15 = !{i32 1, !"PIC Level", i32 2}
+!16 = !{!"clang version 3.7.0 (trunk 242039) (llvm/trunk 242046)"}
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