1 //===-- llvm/CodeGen/MachineDebugInfo.cpp -----------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by James M. Laskey and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "llvm/CodeGen/MachineDebugInfo.h"
12 #include "llvm/Constants.h"
13 #include "llvm/DerivedTypes.h"
14 #include "llvm/Intrinsics.h"
15 #include "llvm/Instructions.h"
16 #include "llvm/Module.h"
17 #include "llvm/Support/Dwarf.h"
21 // Handle the Pass registration stuff necessary to use TargetData's.
23 RegisterPass<MachineDebugInfo> X("machinedebuginfo", "Debug Information");
26 //===----------------------------------------------------------------------===//
28 /// getGlobalVariablesUsing - Return all of the global variables which have the
29 /// specified value in their initializer somewhere.
31 getGlobalVariablesUsing(Value *V, std::vector<GlobalVariable*> &Result) {
32 // Scan though value users.
33 for (Value::use_iterator I = V->use_begin(), E = V->use_end(); I != E; ++I) {
34 if (GlobalVariable *GV = dyn_cast<GlobalVariable>(*I)) {
35 // If the user is a global variable then add to result.
37 } else if (Constant *C = dyn_cast<Constant>(*I)) {
38 // If the user is a constant variable then scan its users
39 getGlobalVariablesUsing(C, Result);
44 /// getGlobalVariablesUsing - Return all of the global variables that use the
45 /// named global variable.
46 static std::vector<GlobalVariable*>
47 getGlobalVariablesUsing(Module &M, const std::string &RootName) {
48 std::vector<GlobalVariable*> Result; // Global variables matching criteria.
50 // Get the global variable root.
51 GlobalVariable *UseRoot = M.getGlobalVariable(RootName,
52 StructType::get(std::vector<const Type*>()));
54 // If present and linkonce then scan for users.
55 if (UseRoot && UseRoot->hasLinkOnceLinkage()) {
56 getGlobalVariablesUsing(UseRoot, Result);
62 /// getStringValue - Turn an LLVM constant pointer that eventually points to a
63 /// global into a string value. Return an empty string if we can't do it.
65 const static std::string getStringValue(Value *V, unsigned Offset = 0) {
66 if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V)) {
67 if (GV->hasInitializer() && isa<ConstantArray>(GV->getInitializer())) {
68 ConstantArray *Init = cast<ConstantArray>(GV->getInitializer());
69 if (Init->isString()) {
70 std::string Result = Init->getAsString();
71 if (Offset < Result.size()) {
72 // If we are pointing INTO The string, erase the beginning...
73 Result.erase(Result.begin(), Result.begin()+Offset);
75 // Take off the null terminator, and any string fragments after it.
76 std::string::size_type NullPos = Result.find_first_of((char)0);
77 if (NullPos != std::string::npos)
78 Result.erase(Result.begin()+NullPos, Result.end());
83 } else if (Constant *C = dyn_cast<Constant>(V)) {
84 if (GlobalValue *GV = dyn_cast<GlobalValue>(C))
85 return getStringValue(GV, Offset);
86 else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
87 if (CE->getOpcode() == Instruction::GetElementPtr) {
88 // Turn a gep into the specified offset.
89 if (CE->getNumOperands() == 3 &&
90 cast<Constant>(CE->getOperand(1))->isNullValue() &&
91 isa<ConstantInt>(CE->getOperand(2))) {
92 return getStringValue(CE->getOperand(0),
93 Offset+cast<ConstantInt>(CE->getOperand(2))->getRawValue());
101 //===----------------------------------------------------------------------===//
103 DebugInfoWrapper::DebugInfoWrapper(GlobalVariable *G)
105 , IC(dyn_cast<ConstantStruct>(GV->getInitializer())) {
106 assert(IC && "llvm.db.global is missing structured constant");
109 //===----------------------------------------------------------------------===//
111 CompileUnitWrapper::CompileUnitWrapper(GlobalVariable *G)
112 : DebugInfoWrapper(G)
114 // FIXME - should probably ease up on the number of operands (version.)
115 assert(IC->getNumOperands() == 7 &&
116 "Compile unit does not have correct number of operands");
119 /// getTag - Return the compile unit's tag number. Currently should be
121 unsigned CompileUnitWrapper::getTag() const {
122 ConstantUInt *CI = dyn_cast<ConstantUInt>(IC->getOperand(0));
123 assert(CI && "Compile unit tag not an unsigned integer");
124 return CI->getValue();
127 /// isCorrectDebugVersion - Return true if is the correct llvm debug version.
128 /// Currently the value is 0 (zero.) If the value is is not correct then
129 /// ignore all debug information.
130 bool CompileUnitWrapper::isCorrectDebugVersion() const {
131 ConstantUInt *CI = dyn_cast<ConstantUInt>(IC->getOperand(1));
132 assert(CI && "Compile unit debug version not an unsigned integer");
133 return CI->getValue() == 0;
136 /// getLanguage - Return the compile unit's language number (ex. DW_LANG_C89.)
138 unsigned CompileUnitWrapper::getLanguage() const {
139 ConstantUInt *CI = dyn_cast<ConstantUInt>(IC->getOperand(2));
140 assert(CI && "Compile unit language number not an unsigned integer");
141 return CI->getValue();
144 /// getFileName - Return the compile unit's file name.
146 const std::string CompileUnitWrapper::getFileName() const {
147 return getStringValue(IC->getOperand(3));
150 /// getDirectory - Return the compile unit's file directory.
152 const std::string CompileUnitWrapper::getDirectory() const {
153 return getStringValue(IC->getOperand(4));
156 /// getProducer - Return the compile unit's generator name.
158 const std::string CompileUnitWrapper::getProducer() const {
159 return getStringValue(IC->getOperand(5));
162 //===----------------------------------------------------------------------===//
164 GlobalWrapper::GlobalWrapper(GlobalVariable *G)
165 : DebugInfoWrapper(G)
167 // FIXME - should probably ease up on the number of operands (version.)
168 assert(IC->getNumOperands() == 8 &&
169 "Global does not have correct number of operands");
172 /// getTag - Return the global's tag number. Currently should be
173 /// DW_TAG_variable or DW_TAG_subprogram.
174 unsigned GlobalWrapper::getTag() const {
175 ConstantUInt *CI = dyn_cast<ConstantUInt>(IC->getOperand(0));
176 assert(CI && "Global tag not an unsigned integer");
177 return CI->getValue();
180 /// getContext - Return the "lldb.compile_unit" context global.
182 GlobalVariable *GlobalWrapper::getContext() const {
183 return cast<GlobalVariable>(IC->getOperand(1));
186 /// getName - Return the name of the global.
188 const std::string GlobalWrapper::getName() const {
189 return getStringValue(IC->getOperand(2));
192 /// getType - Return the type of the global.
194 const GlobalVariable *GlobalWrapper::getType() const {
195 return cast<GlobalVariable>(IC->getOperand(4));
198 /// isStatic - Return true if the global is static.
200 bool GlobalWrapper::isStatic() const {
201 ConstantBool *CB = dyn_cast<ConstantBool>(IC->getOperand(5));
202 assert(CB && "Global static flag is not boolean");
203 return CB->getValue();
206 /// isDefinition - Return true if the global is a definition.
208 bool GlobalWrapper::isDefinition() const {
209 ConstantBool *CB = dyn_cast<ConstantBool>(IC->getOperand(6));
210 assert(CB && "Global definition flag is not boolean");
211 return CB->getValue();
214 /// getGlobalVariable - Return the global variable (tag == DW_TAG_variable.)
216 GlobalVariable *GlobalWrapper::getGlobalVariable() const {
217 ConstantExpr *CE = dyn_cast<ConstantExpr>(IC->getOperand(7));
218 assert(CE && CE->getOpcode() == Instruction::Cast &&
219 "Global location is not a cast of GlobalVariable");
220 GlobalVariable *GV = dyn_cast<GlobalVariable>(CE->getOperand(0));
221 assert(GV && "Global location is not a cast of GlobalVariable");
225 //===----------------------------------------------------------------------===//
228 MachineDebugInfo::MachineDebugInfo()
236 MachineDebugInfo::~MachineDebugInfo() {
240 /// doInitialization - Initialize the debug state for a new module.
242 bool MachineDebugInfo::doInitialization() {
246 /// doFinalization - Tear down the debug state after completion of a module.
248 bool MachineDebugInfo::doFinalization() {
252 /// AnalyzeModule - Scan the module for global debug information.
254 void MachineDebugInfo::AnalyzeModule(Module &M) {
255 SetupCompileUnits(M);
258 /// SetupCompileUnits - Set up the unique vector of compile units.
260 void MachineDebugInfo::SetupCompileUnits(Module &M) {
261 // Get vector of all debug compile units.
262 std::vector<GlobalVariable*> Globals =
263 getGlobalVariablesUsing(M, "llvm.dbg.translation_units");
265 // Scan all compile unit globals.
266 for (unsigned i = 0, N = Globals.size(); i < N; ++i) {
267 // Create wrapper for compile unit.
268 CompileUnitWrapper CUI(Globals[i]);
270 if (CUI.isCorrectDebugVersion()) CompileUnits.insert(CUI);
273 // If there any bad compile units then suppress debug information
274 if (CompileUnits.size() != Globals.size()) CompileUnits.reset();
277 /// getCompileUnits - Return a vector of debug compile units.
279 const UniqueVector<CompileUnitWrapper> MachineDebugInfo::getCompileUnits()const{
283 /// getGlobalVariables - Return a vector of debug global variables.
285 std::vector<GlobalWrapper> MachineDebugInfo::getGlobalVariables(Module &M) {
286 // Get vector of all debug global objects.
287 std::vector<GlobalVariable*> Globals =
288 getGlobalVariablesUsing(M, "llvm.dbg.globals");
290 // Accumulation of global variables.
291 std::vector<GlobalWrapper> GlobalVariables;
293 // FIXME - skip until globals have new format
296 for (unsigned i = 0, N = Globals.size(); i < N; ++i) {
297 // Create wrapper for global.
298 GlobalWrapper GW(Globals[i]);
299 // If the global is a variable then add to result.
300 if (GW.getTag() == DW_TAG_variable) GlobalVariables.push_back(GW);
304 return GlobalVariables;