llvm-project/clang/lib/CodeGen/CGDebugInfo.cpp

551 lines
21 KiB
C++

//===--- CGDebugInfo.cpp - Emit Debug Information for a Module ------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This coordinates the debug information generation while generating code.
//
//===----------------------------------------------------------------------===//
#include "CGDebugInfo.h"
#include "CodeGenModule.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/Decl.h"
#include "clang/AST/Expr.h"
#include "clang/AST/RecordLayout.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Basic/FileManager.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Instructions.h"
#include "llvm/Intrinsics.h"
#include "llvm/Module.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/Dwarf.h"
#include "llvm/Target/TargetMachine.h"
using namespace clang;
using namespace clang::CodeGen;
CGDebugInfo::CGDebugInfo(CodeGenModule *m)
: M(m), DebugFactory(M->getModule()) {
}
CGDebugInfo::~CGDebugInfo() {
assert(RegionStack.empty() && "Region stack mismatch, stack not empty!");
}
void CGDebugInfo::setLocation(SourceLocation Loc) {
if (Loc.isValid())
CurLoc = M->getContext().getSourceManager().getLogicalLoc(Loc);
}
/// getOrCreateCompileUnit - Get the compile unit from the cache or create a new
/// one if necessary. This returns null for invalid source locations.
llvm::DICompileUnit CGDebugInfo::getOrCreateCompileUnit(SourceLocation Loc) {
if (Loc.isInvalid())
return llvm::DICompileUnit();
SourceManager &SM = M->getContext().getSourceManager();
const FileEntry *FE = SM.getFileEntryForLoc(Loc);
if (FE == 0) return llvm::DICompileUnit();
// See if this compile unit has been used before.
llvm::DICompileUnit &Unit = CompileUnitCache[FE];
if (!Unit.isNull()) return Unit;
// Get source file information.
const char *FileName = FE->getName();
const char *DirName = FE->getDir()->getName();
// Create new compile unit.
// FIXME: Handle other language IDs as well.
// FIXME: Do not know how to get clang version yet.
return Unit = DebugFactory.CreateCompileUnit(llvm::dwarf::DW_LANG_C89,
FileName, DirName, "clang");
}
/// getOrCreateBuiltinType - Get the Basic type from the cache or create a new
/// one if necessary.
llvm::DIType CGDebugInfo::CreateType(const BuiltinType *BT,
llvm::DICompileUnit Unit){
unsigned Encoding = 0;
switch (BT->getKind()) {
default:
case BuiltinType::Void:
return llvm::DIType();
case BuiltinType::UChar:
case BuiltinType::Char_U: Encoding = llvm::dwarf::DW_ATE_unsigned_char; break;
case BuiltinType::Char_S:
case BuiltinType::SChar: Encoding = llvm::dwarf::DW_ATE_signed_char; break;
case BuiltinType::UShort:
case BuiltinType::UInt:
case BuiltinType::ULong:
case BuiltinType::ULongLong: Encoding = llvm::dwarf::DW_ATE_unsigned; break;
case BuiltinType::Short:
case BuiltinType::Int:
case BuiltinType::Long:
case BuiltinType::LongLong: Encoding = llvm::dwarf::DW_ATE_signed; break;
case BuiltinType::Bool: Encoding = llvm::dwarf::DW_ATE_boolean; break;
case BuiltinType::Float:
case BuiltinType::Double: Encoding = llvm::dwarf::DW_ATE_float; break;
}
// Bit size, align and offset of the type.
uint64_t Size = M->getContext().getTypeSize(BT);
uint64_t Align = M->getContext().getTypeAlign(BT);
uint64_t Offset = 0;
return DebugFactory.CreateBasicType(Unit, BT->getName(), Unit, 0, Size, Align,
Offset, /*flags*/ 0, Encoding);
}
/// getOrCreateCVRType - Get the CVR qualified type from the cache or create
/// a new one if necessary.
llvm::DIType CGDebugInfo::CreateCVRType(QualType Ty, llvm::DICompileUnit Unit) {
// We will create one Derived type for one qualifier and recurse to handle any
// additional ones.
llvm::DIType FromTy;
unsigned Tag;
if (Ty.isConstQualified()) {
Tag = llvm::dwarf::DW_TAG_const_type;
Ty.removeConst();
FromTy = getOrCreateType(Ty, Unit);
} else if (Ty.isVolatileQualified()) {
Tag = llvm::dwarf::DW_TAG_volatile_type;
Ty.removeVolatile();
FromTy = getOrCreateType(Ty, Unit);
} else {
assert(Ty.isRestrictQualified() && "Unknown type qualifier for debug info");
Tag = llvm::dwarf::DW_TAG_restrict_type;
Ty.removeRestrict();
FromTy = getOrCreateType(Ty, Unit);
}
// No need to fill in the Name, Line, Size, Alignment, Offset in case of
// CVR derived types.
return DebugFactory.CreateDerivedType(Tag, Unit, "", llvm::DICompileUnit(),
0, 0, 0, 0, 0, FromTy);
}
llvm::DIType CGDebugInfo::CreateType(const PointerType *Ty,
llvm::DICompileUnit Unit) {
llvm::DIType EltTy = getOrCreateType(Ty->getPointeeType(), Unit);
// Bit size, align and offset of the type.
uint64_t Size = M->getContext().getTypeSize(Ty);
uint64_t Align = M->getContext().getTypeAlign(Ty);
return DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_pointer_type, Unit,
"", llvm::DICompileUnit(),
0, Size, Align, 0, 0, EltTy);
}
llvm::DIType CGDebugInfo::CreateType(const TypedefType *Ty,
llvm::DICompileUnit Unit) {
// Typedefs are derived from some other type. If we have a typedef of a
// typedef, make sure to emit the whole chain.
llvm::DIType Src = getOrCreateType(Ty->getDecl()->getUnderlyingType(), Unit);
// We don't set size information, but do specify where the typedef was
// declared.
std::string TyName = Ty->getDecl()->getNameAsString();
SourceLocation DefLoc = Ty->getDecl()->getLocation();
llvm::DICompileUnit DefUnit = getOrCreateCompileUnit(DefLoc);
SourceManager &SM = M->getContext().getSourceManager();
uint64_t Line = SM.getLogicalLineNumber(DefLoc);
return DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_typedef, Unit,
TyName, DefUnit, Line, 0, 0, 0, 0, Src);
}
llvm::DIType CGDebugInfo::CreateType(const FunctionType *Ty,
llvm::DICompileUnit Unit) {
llvm::SmallVector<llvm::DIDescriptor, 16> EltTys;
// Add the result type at least.
EltTys.push_back(getOrCreateType(Ty->getResultType(), Unit));
// Set up remainder of arguments if there is a prototype.
// FIXME: IF NOT, HOW IS THIS REPRESENTED? llvm-gcc doesn't represent '...'!
if (const FunctionTypeProto *FTP = dyn_cast<FunctionTypeProto>(Ty)) {
for (unsigned i = 0, e = FTP->getNumArgs(); i != e; ++i)
EltTys.push_back(getOrCreateType(FTP->getArgType(i), Unit));
} else {
// FIXME: Handle () case in C. llvm-gcc doesn't do it either.
}
llvm::DIArray EltTypeArray =
DebugFactory.GetOrCreateArray(&EltTys[0], EltTys.size());
return DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_subroutine_type,
Unit, "", llvm::DICompileUnit(),
0, 0, 0, 0, 0,
llvm::DIType(), EltTypeArray);
}
/// getOrCreateRecordType - get structure or union type.
llvm::DIType CGDebugInfo::CreateType(const RecordType *Ty,
llvm::DICompileUnit Unit) {
RecordDecl *Decl = Ty->getDecl();
unsigned Tag;
if (Decl->isStruct())
Tag = llvm::dwarf::DW_TAG_structure_type;
else if (Decl->isUnion())
Tag = llvm::dwarf::DW_TAG_union_type;
else {
assert(Decl->isClass() && "Unknown RecordType!");
Tag = llvm::dwarf::DW_TAG_class_type;
}
SourceManager &SM = M->getContext().getSourceManager();
// Get overall information about the record type for the debug info.
std::string Name = Decl->getNameAsString();
llvm::DICompileUnit DefUnit = getOrCreateCompileUnit(Decl->getLocation());
uint64_t Line = SM.getLogicalLineNumber(Decl->getLocation());
// Records and classes and unions can all be recursive. To handle them, we
// first generate a debug descriptor for the struct as a forward declaration.
// Then (if it is a definition) we go through and get debug info for all of
// its members. Finally, we create a descriptor for the complete type (which
// may refer to the forward decl if the struct is recursive) and replace all
// uses of the forward declaration with the final definition.
llvm::DIType FwdDecl =
DebugFactory.CreateCompositeType(Tag, Unit, Name, DefUnit, Line, 0, 0, 0, 0,
llvm::DIType(), llvm::DIArray());
// If this is just a forward declaration, return it.
if (!Decl->getDefinition(M->getContext()))
return FwdDecl;
// Otherwise, insert it into the TypeCache so that recursive uses will find
// it.
TypeCache[QualType(Ty, 0).getAsOpaquePtr()] = FwdDecl;
// Convert all the elements.
llvm::SmallVector<llvm::DIDescriptor, 16> EltTys;
const ASTRecordLayout &RL = M->getContext().getASTRecordLayout(Decl);
unsigned FieldNo = 0;
for (RecordDecl::field_iterator I = Decl->field_begin(),
E = Decl->field_end();
I != E; ++I, ++FieldNo) {
FieldDecl *Field = *I;
llvm::DIType FieldTy = getOrCreateType(Field->getType(), Unit);
std::string FieldName = Field->getNameAsString();
// Get the location for the field.
SourceLocation FieldDefLoc = Field->getLocation();
llvm::DICompileUnit FieldDefUnit = getOrCreateCompileUnit(FieldDefLoc);
uint64_t FieldLine = SM.getLogicalLineNumber(FieldDefLoc);
// Bit size, align and offset of the type.
uint64_t FieldSize = M->getContext().getTypeSize(Ty);
uint64_t FieldAlign = M->getContext().getTypeAlign(Ty);
uint64_t FieldOffset = RL.getFieldOffset(FieldNo);
// Create a DW_TAG_member node to remember the offset of this field in the
// struct. FIXME: This is an absolutely insane way to capture this
// information. When we gut debug info, this should be fixed.
FieldTy = DebugFactory.CreateDerivedType(llvm::dwarf::DW_TAG_member, Unit,
FieldName, FieldDefUnit,
FieldLine, FieldSize, FieldAlign,
FieldOffset, 0, FieldTy);
EltTys.push_back(FieldTy);
}
llvm::DIArray Elements =
DebugFactory.GetOrCreateArray(&EltTys[0], EltTys.size());
// Bit size, align and offset of the type.
uint64_t Size = M->getContext().getTypeSize(Ty);
uint64_t Align = M->getContext().getTypeAlign(Ty);
llvm::DIType RealDecl =
DebugFactory.CreateCompositeType(Tag, Unit, Name, DefUnit, Line, Size,
Align, 0, 0, llvm::DIType(), Elements);
// Now that we have a real decl for the struct, replace anything using the
// old decl with the new one. This will recursively update the debug info.
FwdDecl.getGV()->replaceAllUsesWith(RealDecl.getGV());
FwdDecl.getGV()->eraseFromParent();
return RealDecl;
}
llvm::DIType CGDebugInfo::CreateType(const EnumType *Ty,
llvm::DICompileUnit Unit) {
EnumDecl *Decl = Ty->getDecl();
llvm::SmallVector<llvm::DIDescriptor, 32> Enumerators;
// Create DIEnumerator elements for each enumerator.
for (EnumDecl::enumerator_iterator Enum = Decl->enumerator_begin(),
EnumEnd = Decl->enumerator_end();
Enum != EnumEnd; ++Enum) {
Enumerators.push_back(DebugFactory.CreateEnumerator(Enum->getNameAsString(),
Enum->getInitVal().getZExtValue()));
}
// Return a CompositeType for the enum itself.
llvm::DIArray EltArray =
DebugFactory.GetOrCreateArray(&Enumerators[0], Enumerators.size());
std::string EnumName = Decl->getNameAsString();
SourceLocation DefLoc = Decl->getLocation();
llvm::DICompileUnit DefUnit = getOrCreateCompileUnit(DefLoc);
SourceManager &SM = M->getContext().getSourceManager();
uint64_t Line = SM.getLogicalLineNumber(DefLoc);
// Size and align of the type.
uint64_t Size = M->getContext().getTypeSize(Ty);
uint64_t Align = M->getContext().getTypeAlign(Ty);
return DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_enumeration_type,
Unit, EnumName, DefUnit, Line,
Size, Align, 0, 0,
llvm::DIType(), EltArray);
}
llvm::DIType CGDebugInfo::CreateType(const TagType *Ty,
llvm::DICompileUnit Unit) {
if (const RecordType *RT = dyn_cast<RecordType>(Ty))
return CreateType(RT, Unit);
else if (const EnumType *ET = dyn_cast<EnumType>(Ty))
return CreateType(ET, Unit);
return llvm::DIType();
}
llvm::DIType CGDebugInfo::CreateType(const ArrayType *Ty,
llvm::DICompileUnit Unit) {
uint64_t Size;
uint64_t Align;
if (const VariableArrayType *VAT = dyn_cast<VariableArrayType>(Ty)) {
Size = 0;
Align =
M->getContext().getTypeSize(M->getContext().getBaseElementType(VAT));
} else {
// Size and align of the whole array, not the element type.
Size = M->getContext().getTypeSize(Ty);
Align = M->getContext().getTypeAlign(Ty);
}
// Add the dimensions of the array. FIXME: This loses CV qualifiers from
// interior arrays, do we care? Why aren't nested arrays represented the
// obvious/recursive way?
llvm::SmallVector<llvm::DIDescriptor, 8> Subscripts;
QualType EltTy(Ty, 0);
while ((Ty = dyn_cast<ArrayType>(EltTy))) {
uint64_t Upper = 0;
if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(Ty))
Upper = CAT->getSize().getZExtValue() - 1;
// FIXME: Verify this is right for VLAs.
Subscripts.push_back(DebugFactory.GetOrCreateSubrange(0, Upper));
EltTy = Ty->getElementType();
}
llvm::DIArray SubscriptArray =
DebugFactory.GetOrCreateArray(&Subscripts[0], Subscripts.size());
return DebugFactory.CreateCompositeType(llvm::dwarf::DW_TAG_array_type,
Unit, "", llvm::DICompileUnit(),
0, Size, Align, 0, 0,
getOrCreateType(EltTy, Unit),
SubscriptArray);
}
/// getOrCreateType - Get the type from the cache or create a new
/// one if necessary.
llvm::DIType CGDebugInfo::getOrCreateType(QualType Ty,
llvm::DICompileUnit Unit) {
if (Ty.isNull())
return llvm::DIType();
// Check to see if the compile unit already has created this type.
llvm::DIType &Slot = TypeCache[Ty.getAsOpaquePtr()];
if (!Slot.isNull()) return Slot;
// Handle CVR qualifiers, which recursively handles what they refer to.
if (Ty.getCVRQualifiers())
return Slot = CreateCVRType(Ty, Unit);
// Work out details of type.
switch (Ty->getTypeClass()) {
case Type::Complex:
case Type::Reference:
case Type::Vector:
case Type::ExtVector:
case Type::ASQual:
case Type::ObjCInterface:
case Type::ObjCQualifiedInterface:
case Type::ObjCQualifiedId:
default:
return llvm::DIType();
case Type::Builtin: Slot = CreateType(cast<BuiltinType>(Ty), Unit); break;
case Type::Pointer: Slot = CreateType(cast<PointerType>(Ty), Unit); break;
case Type::TypeName: Slot = CreateType(cast<TypedefType>(Ty), Unit); break;
case Type::Tagged: Slot = CreateType(cast<TagType>(Ty), Unit); break;
case Type::FunctionProto:
case Type::FunctionNoProto:
return Slot = CreateType(cast<FunctionType>(Ty), Unit);
case Type::ConstantArray:
case Type::VariableArray:
case Type::IncompleteArray:
return Slot = CreateType(cast<ArrayType>(Ty), Unit);
case Type::TypeOfExp:
return Slot = getOrCreateType(cast<TypeOfExpr>(Ty)->getUnderlyingExpr()
->getType(), Unit);
case Type::TypeOfTyp:
return Slot = getOrCreateType(cast<TypeOfType>(Ty)->getUnderlyingType(),
Unit);
}
return Slot;
}
/// EmitFunctionStart - Constructs the debug code for entering a function -
/// "llvm.dbg.func.start.".
void CGDebugInfo::EmitFunctionStart(const char *Name, QualType ReturnType,
llvm::Function *Fn,
CGBuilderTy &Builder) {
// FIXME: Why is this using CurLoc???
llvm::DICompileUnit Unit = getOrCreateCompileUnit(CurLoc);
SourceManager &SM = M->getContext().getSourceManager();
uint64_t LineNo = SM.getLogicalLineNumber(CurLoc);
llvm::DISubprogram SP =
DebugFactory.CreateSubprogram(Unit, Name, Name, "", Unit, LineNo,
getOrCreateType(ReturnType, Unit),
Fn->hasInternalLinkage(), true/*definition*/);
DebugFactory.InsertSubprogramStart(SP, Builder.GetInsertBlock());
// Push function on region stack.
RegionStack.push_back(SP);
}
void CGDebugInfo::EmitStopPoint(llvm::Function *Fn, CGBuilderTy &Builder) {
if (CurLoc.isInvalid() || CurLoc.isMacroID()) return;
// Don't bother if things are the same as last time.
SourceManager &SM = M->getContext().getSourceManager();
if (CurLoc == PrevLoc
|| (SM.getLineNumber(CurLoc) == SM.getLineNumber(PrevLoc)
&& SM.isFromSameFile(CurLoc, PrevLoc)))
return;
// Update last state.
PrevLoc = CurLoc;
// Get the appropriate compile unit.
llvm::DICompileUnit Unit = getOrCreateCompileUnit(CurLoc);
DebugFactory.InsertStopPoint(Unit, SM.getLogicalLineNumber(CurLoc),
SM.getLogicalColumnNumber(CurLoc),
Builder.GetInsertBlock());
}
/// EmitRegionStart- Constructs the debug code for entering a declarative
/// region - "llvm.dbg.region.start.".
void CGDebugInfo::EmitRegionStart(llvm::Function *Fn, CGBuilderTy &Builder) {
llvm::DIDescriptor D;
if (!RegionStack.empty())
D = RegionStack.back();
D = DebugFactory.CreateBlock(D);
RegionStack.push_back(D);
DebugFactory.InsertRegionStart(D, Builder.GetInsertBlock());
}
/// EmitRegionEnd - Constructs the debug code for exiting a declarative
/// region - "llvm.dbg.region.end."
void CGDebugInfo::EmitRegionEnd(llvm::Function *Fn, CGBuilderTy &Builder) {
assert(!RegionStack.empty() && "Region stack mismatch, stack empty!");
// Provide an region stop point.
EmitStopPoint(Fn, Builder);
DebugFactory.InsertRegionEnd(RegionStack.back(), Builder.GetInsertBlock());
RegionStack.pop_back();
}
/// EmitDeclare - Emit local variable declaration debug info.
void CGDebugInfo::EmitDeclare(const VarDecl *Decl, unsigned Tag,
llvm::Value *Storage, CGBuilderTy &Builder) {
assert(!RegionStack.empty() && "Region stack mismatch, stack empty!");
// Get location information.
SourceManager &SM = M->getContext().getSourceManager();
uint64_t Line = SM.getLogicalLineNumber(Decl->getLocation());
llvm::DICompileUnit Unit = getOrCreateCompileUnit(Decl->getLocation());
// Create the descriptor for the variable.
llvm::DIVariable D =
DebugFactory.CreateVariable(Tag, RegionStack.back(),Decl->getNameAsString(),
Unit, Line,
getOrCreateType(Decl->getType(), Unit));
// Insert an llvm.dbg.declare into the current block.
DebugFactory.InsertDeclare(Storage, D, Builder.GetInsertBlock());
}
void CGDebugInfo::EmitDeclareOfAutoVariable(const VarDecl *Decl,
llvm::Value *Storage,
CGBuilderTy &Builder) {
EmitDeclare(Decl, llvm::dwarf::DW_TAG_auto_variable, Storage, Builder);
}
/// EmitDeclareOfArgVariable - Emit call to llvm.dbg.declare for an argument
/// variable declaration.
void CGDebugInfo::EmitDeclareOfArgVariable(const VarDecl *Decl, llvm::Value *AI,
CGBuilderTy &Builder) {
EmitDeclare(Decl, llvm::dwarf::DW_TAG_arg_variable, AI, Builder);
}
/// EmitGlobalVariable - Emit information about a global variable.
void CGDebugInfo::EmitGlobalVariable(llvm::GlobalVariable *Var,
const VarDecl *Decl) {
// Create global variable debug descriptor.
llvm::DICompileUnit Unit = getOrCreateCompileUnit(Decl->getLocation());
SourceManager &SM = M->getContext().getSourceManager();
uint64_t LineNo = SM.getLogicalLineNumber(Decl->getLocation());
std::string Name = Decl->getNameAsString();
QualType T = Decl->getType();
if (T->isIncompleteArrayType()) {
// CodeGen turns int[] into int[1] so we'll do the same here.
llvm::APSInt ConstVal(32);
ConstVal = 1;
QualType ET = M->getContext().getAsArrayType(T)->getElementType();
T = M->getContext().getConstantArrayType(ET, ConstVal,
ArrayType::Normal, 0);
}
DebugFactory.CreateGlobalVariable(Unit, Name, Name, "", Unit, LineNo,
getOrCreateType(T, Unit),
Var->hasInternalLinkage(),
true/*definition*/, Var);
}