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Initial checkin of the LLVM source-level debugger. This is still not finished,

Browse Source 
by any stretch of the imagination, but it is pretty cool and works :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10685 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2004-01-05 05:25:10 +00:00
parent 4575dcb587
commit 2eacf26aa6
11 changed files with 1983 additions and 0 deletions
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//===-- Debugger.cpp - LLVM debugger library implementation ---------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the main implementation of the LLVM debugger library.
//
//===----------------------------------------------------------------------===//
#include "llvm/Debugger/Debugger.h"
#include "llvm/Module.h"
#include "llvm/ModuleProvider.h"
#include "llvm/Bytecode/Reader.h"
#include "llvm/Debugger/InferiorProcess.h"
#include "Support/StringExtras.h"
using namespace llvm;
/// Debugger constructor - Initialize the debugger to its initial, empty, state.
///
Debugger::Debugger() : Environment(0), Program(0), Process(0) {
}
Debugger::~Debugger() {
// Killing the program could throw an exception. We don't want to progagate
// the exception out of our destructor though.
try {
killProgram();
} catch (const char *) {
} catch (const std::string &) {
}
unloadProgram();
}
/// getProgramPath - Get the path of the currently loaded program, or an
/// empty string if none is loaded.
std::string Debugger::getProgramPath() const {
return Program ? Program->getModuleIdentifier() : "";
}
static Module *
getMaterializedModuleProvider(const std::string &Filename) {
try {
std::auto_ptr<ModuleProvider> Result(getBytecodeModuleProvider(Filename));
if (!Result.get()) return 0;
Result->materializeModule();
return Result.release()->releaseModule();
} catch (...) {
return 0;
}
}
/// loadProgram - If a program is currently loaded, unload it. Then search
/// the PATH for the specified program, loading it when found. If the
/// specified program cannot be found, an exception is thrown to indicate the
/// error.
void Debugger::loadProgram(const std::string &Filename) {
if ((Program = getMaterializedModuleProvider(Filename)) ||
(Program = getMaterializedModuleProvider(Filename+".bc")))
return; // Successfully loaded the program.
// Search the program path for the file...
if (const char *PathS = getenv("PATH")) {
std::string Path = PathS;
std::string Directory = getToken(Path, ":");
while (!Directory.empty()) {
if ((Program = getMaterializedModuleProvider(Directory +"/"+ Filename)) ||
(Program = getMaterializedModuleProvider(Directory +"/"+ Filename
+ ".bc")))
return; // Successfully loaded the program.
Directory = getToken(Path, ":");
}
}
throw "Could not find program '" + Filename + "'!";
}
/// unloadProgram - If a program is running, kill it, then unload all traces
/// of the current program. If no program is loaded, this method silently
/// succeeds.
void Debugger::unloadProgram() {
if (!isProgramLoaded()) return;
killProgram();
delete Program;
Program = 0;
}
/// createProgram - Create an instance of the currently loaded program,
/// killing off any existing one. This creates the program and stops it at
/// the first possible moment. If there is no program loaded or if there is a
/// problem starting the program, this method throws an exception.
void Debugger::createProgram() {
if (!isProgramLoaded())
throw "Cannot start program: none is loaded.";
// Kill any existing program.
killProgram();
// Add argv[0] to the arguments vector..
std::vector<std::string> Args(ProgramArguments);
Args.insert(Args.begin(), getProgramPath());
// Start the new program... this could throw if the program cannot be started.
Process = InferiorProcess::create(Program, Args, Environment);
}
/// killProgram - If the program is currently executing, kill off the
/// process and free up any state related to the currently running program. If
/// there is no program currently running, this just silently succeeds.
void Debugger::killProgram() {
// The destructor takes care of the dirty work.
delete Process;
Process = 0;
}
/// stepProgram - Implement the 'step' command, continuing execution until
/// the next possible stop point.
void Debugger::stepProgram() {
assert(isProgramRunning() && "Cannot step if the program isn't running!");
try {
Process->stepProgram();
} catch (InferiorProcessDead &IPD) {
delete Process;
Process = 0;
throw NonErrorException("The program stopped with exit code " +
itostr(IPD.getExitCode()));
}
}
/// nextProgram - Implement the 'next' command, continuing execution until
/// the next possible stop point that is in the current function.
void Debugger::nextProgram() {
assert(isProgramRunning() && "Cannot next if the program isn't running!");
try {
// This should step the process. If the process enters a function, then it
// should 'finish' it. However, figuring this out is tricky. In
// particular, the program can do any of:
// 0. Not change current frame.
// 1. Entering or exiting a region within the current function
// (which changes the frame ID, but which we shouldn't 'finish')
// 2. Exiting the current function (which changes the frame ID)
// 3. Entering a function (which should be 'finish'ed)
// For this reason, we have to be very careful about when we decide to do
// the 'finish'.
// Get the current frame, but don't trust it. It could change...
void *CurrentFrame = Process->getPreviousFrame(0);
// Don't trust the current frame: get the caller frame.
void *ParentFrame = Process->getPreviousFrame(CurrentFrame);
// Ok, we have some information, run the program one step.
Process->stepProgram();
// Where is the new frame? The most common case, by far is that it has not
// been modified (Case #0), in which case we don't need to do anything more.
void *NewFrame = Process->getPreviousFrame(0);
if (NewFrame != CurrentFrame) {
// Ok, the frame changed. If we are case #1, then the parent frame will
// be identical.
void *NewParentFrame = Process->getPreviousFrame(NewFrame);
if (ParentFrame != NewParentFrame) {
// Ok, now we know we aren't case #0 or #1. Check to see if we entered
// a new function. If so, the parent frame will be "CurrentFrame".
if (CurrentFrame == NewParentFrame)
Process->finishProgram(NewFrame);
}
}
} catch (InferiorProcessDead &IPD) {
delete Process;
Process = 0;
throw NonErrorException("The program stopped with exit code " +
itostr(IPD.getExitCode()));
}
}
/// finishProgram - Implement the 'finish' command, continuing execution
/// until the specified frame ID returns.
void Debugger::finishProgram(void *Frame) {
assert(isProgramRunning() && "Cannot cont if the program isn't running!");
try {
Process->finishProgram(Frame);
} catch (InferiorProcessDead &IPD) {
delete Process;
Process = 0;
throw NonErrorException("The program stopped with exit code " +
itostr(IPD.getExitCode()));
}
}
/// contProgram - Implement the 'cont' command, continuing execution until
/// the next breakpoint is encountered.
void Debugger::contProgram() {
assert(isProgramRunning() && "Cannot cont if the program isn't running!");
try {
Process->contProgram();
} catch (InferiorProcessDead &IPD) {
delete Process;
Process = 0;
throw NonErrorException("The program stopped with exit code " +
itostr(IPD.getExitCode()));
}
}

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##===- lib/Debugger/Makefile -------------------------------*- Makefile -*-===##
#
# The LLVM Compiler Infrastructure
#
# This file was developed by the LLVM research group and is distributed under
# the University of Illinois Open Source License. See LICENSE.TXT for details.
#
##===----------------------------------------------------------------------===##
LEVEL = ../..
LIBRARYNAME = debugger
include $(LEVEL)/Makefile.common

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//===-- ProgramInfo.cpp - Compute and cache info about a program ----------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the ProgramInfo and related classes, by sorting through
// the loaded Module.
//
//===----------------------------------------------------------------------===//
#include "llvm/Debugger/ProgramInfo.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Intrinsics.h"
#include "llvm/iOther.h"
#include "llvm/Module.h"
#include "llvm/Debugger/SourceFile.h"
#include "llvm/Debugger/SourceLanguage.h"
#include "Support/FileUtilities.h"
#include "Support/SlowOperationInformer.h"
#include "Support/STLExtras.h"
using namespace llvm;
/// getGlobalVariablesUsing - Return all of the global variables which have the
/// specified value in their initializer somewhere.
static void getGlobalVariablesUsing(Value *V,
std::vector<GlobalVariable*> &Found) {
for (Value::use_iterator I = V->use_begin(), E = V->use_end(); I != E; ++I) {
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(*I))
Found.push_back(GV);
else if (Constant *C = dyn_cast<Constant>(*I))
getGlobalVariablesUsing(C, Found);
}
}
/// getStringValue - Turn an LLVM constant pointer that eventually points to a
/// global into a string value. Return an empty string if we can't do it.
///
static std::string getStringValue(Value *V, unsigned Offset = 0) {
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V)) {
if (GV->hasInitializer() && isa<ConstantArray>(GV->getInitializer())) {
ConstantArray *Init = cast<ConstantArray>(GV->getInitializer());
if (Init->getType()->getElementType() == Type::SByteTy ||
Init->getType()->getElementType() == Type::UByteTy) {
std::string Result = Init->getAsString();
if (Offset < Result.size()) {
// If we are pointing INTO The string, erase the beginning...
Result.erase(Result.begin(), Result.begin()+Offset);
// Take off the null terminator, and any string fragments after it.
std::string::size_type NullPos = Result.find_first_of((char)0);
if (NullPos != std::string::npos)
Result.erase(Result.begin()+NullPos, Result.end());
return Result;
}
}
}
} else if (Constant *C = dyn_cast<Constant>(V)) {
if (ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(C))
return getStringValue(CPR->getValue(), Offset);
else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
if (CE->getOpcode() == Instruction::GetElementPtr) {
// Turn a gep into the specified offset.
if (CE->getNumOperands() == 3 &&
cast<Constant>(CE->getOperand(1))->isNullValue() &&
isa<ConstantInt>(CE->getOperand(2))) {
return getStringValue(CE->getOperand(0),
Offset+cast<ConstantInt>(CE->getOperand(2))->getRawValue());
}
}
}
}
return "";
}
/// getNextStopPoint - Follow the def-use chains of the specified LLVM value,
/// traversing the use chains until we get to a stoppoint. When we do, return
/// the source location of the stoppoint. If we don't find a stoppoint, return
/// null.
static const GlobalVariable *getNextStopPoint(const Value *V, unsigned &LineNo,
unsigned &ColNo) {
// The use-def chains can fork. As such, we pick the lowest numbered one we
// find.
const GlobalVariable *LastDesc = 0;
unsigned LastLineNo = ~0;
unsigned LastColNo = ~0;
for (Value::use_const_iterator UI = V->use_begin(), E = V->use_end();
UI != E; ++UI) {
bool ShouldRecurse = true;
if (cast<Instruction>(*UI)->getOpcode() == Instruction::PHI) {
// Infinite loops == bad, ignore PHI nodes.
ShouldRecurse = false;
} else if (const CallInst *CI = dyn_cast<CallInst>(*UI)) {
// If we found a stop point, check to see if it is earlier than what we
// already have. If so, remember it.
if (const Function *F = CI->getCalledFunction())
if (F->getIntrinsicID() == Intrinsic::dbg_stoppoint) {
unsigned CurLineNo = ~0, CurColNo = ~0;
const GlobalVariable *CurDesc = 0;
if (const ConstantInt *C = dyn_cast<ConstantInt>(CI->getOperand(2)))
CurLineNo = C->getRawValue();
if (const ConstantInt *C = dyn_cast<ConstantInt>(CI->getOperand(3)))
CurColNo = C->getRawValue();
const Value *Op = CI->getOperand(4);
if (const ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(Op))
Op = CPR->getValue();
if ((CurDesc = dyn_cast<GlobalVariable>(Op)) &&
(LineNo < LastLineNo ||
(LineNo == LastLineNo && ColNo < LastColNo))) {
LastDesc = CurDesc;
LastLineNo = CurLineNo;
LastColNo = CurColNo;
}
ShouldRecurse = false;
}
}
// If this is not a phi node or a stopping point, recursively scan the users
// of this instruction to skip over region.begin's and the like.
if (ShouldRecurse) {
unsigned CurLineNo, CurColNo;
if (const GlobalVariable *GV = getNextStopPoint(*UI, CurLineNo,CurColNo)){
if (LineNo < LastLineNo || (LineNo == LastLineNo && ColNo < LastColNo)){
LastDesc = GV;
LastLineNo = CurLineNo;
LastColNo = CurColNo;
}
}
}
}
if (LastDesc) {
LineNo = LastLineNo != ~0U ? LastLineNo : 0;
ColNo = LastColNo != ~0U ? LastColNo : 0;
}
return LastDesc;
}
//===----------------------------------------------------------------------===//
// SourceFileInfo implementation
//
SourceFileInfo::SourceFileInfo(const GlobalVariable *Desc,
const SourceLanguage &Lang)
: Language(&Lang), Descriptor(Desc) {
Version = 0;
SourceText = 0;
if (Desc && Desc->hasInitializer())
if (ConstantStruct *CS = dyn_cast<ConstantStruct>(Desc->getInitializer()))
if (CS->getNumOperands() > 4) {
if (ConstantUInt *CUI = dyn_cast<ConstantUInt>(CS->getOperand(1)))
Version = CUI->getValue();
BaseName = getStringValue(CS->getOperand(3));
Directory = getStringValue(CS->getOperand(4));
}
}
SourceFileInfo::~SourceFileInfo() {
delete SourceText;
}
SourceFile &SourceFileInfo::getSourceText() const {
// FIXME: this should take into account the source search directories!
if (SourceText == 0) // Read the file in if we haven't already.
if (!Directory.empty() && FileOpenable(Directory+"/"+BaseName))
SourceText = new SourceFile(Directory+"/"+BaseName, Descriptor);
else
SourceText = new SourceFile(BaseName, Descriptor);
return *SourceText;
}
//===----------------------------------------------------------------------===//
// SourceFunctionInfo implementation
//
SourceFunctionInfo::SourceFunctionInfo(ProgramInfo &PI,
const GlobalVariable *Desc)
: Descriptor(Desc) {
LineNo = ColNo = 0;
if (Desc && Desc->hasInitializer())
if (ConstantStruct *CS = dyn_cast<ConstantStruct>(Desc->getInitializer()))
if (CS->getNumOperands() > 2) {
// Entry #1 is the file descriptor.
if (const ConstantPointerRef *CPR =
dyn_cast<ConstantPointerRef>(CS->getOperand(1)))
if (const GlobalVariable *GV =
dyn_cast<GlobalVariable>(CPR->getValue()))
SourceFile = &PI.getSourceFile(GV);
// Entry #2 is the function name.
Name = getStringValue(CS->getOperand(2));
}
}
/// getSourceLocation - This method returns the location of the first stopping
/// point in the function.
void SourceFunctionInfo::getSourceLocation(unsigned &RetLineNo,
unsigned &RetColNo) const {
// If we haven't computed this yet...
if (!LineNo) {
// Look at all of the users of the function descriptor, looking for calls to
// %llvm.dbg.func.start.
for (Value::use_const_iterator UI = Descriptor->use_begin(),
E = Descriptor->use_end(); UI != E; ++UI)
if (const CallInst *CI = dyn_cast<CallInst>(*UI))
if (const Function *F = CI->getCalledFunction())
if (F->getIntrinsicID() == Intrinsic::dbg_func_start) {
// We found the start of the function. Check to see if there are
// any stop points on the use-list of the function start.
const GlobalVariable *SD = getNextStopPoint(CI, LineNo, ColNo);
if (SD) { // We found the first stop point!
// This is just a sanity check.
if (getSourceFile().getDescriptor() != SD)
std::cout << "WARNING: first line of function is not in the"
" file that the function descriptor claims it is in.\n";
break;
}
}
}
RetLineNo = LineNo; RetColNo = ColNo;
}
//===----------------------------------------------------------------------===//
// ProgramInfo implementation
//
ProgramInfo::ProgramInfo(Module *m) : M(m) {
assert(M && "Cannot create program information with a null module!");
ProgramTimeStamp = getFileTimestamp(M->getModuleIdentifier());
SourceFilesIsComplete = false;
SourceFunctionsIsComplete = false;
}
ProgramInfo::~ProgramInfo() {
// Delete cached information about source program objects...
for (std::map<const GlobalVariable*, SourceFileInfo*>::iterator
I = SourceFiles.begin(), E = SourceFiles.end(); I != E; ++I)
delete I->second;
for (std::map<const GlobalVariable*, SourceFunctionInfo*>::iterator
I = SourceFunctions.begin(), E = SourceFunctions.end(); I != E; ++I)
delete I->second;
// Delete the source language caches.
for (unsigned i = 0, e = LanguageCaches.size(); i != e; ++i)
delete LanguageCaches[i].second;
}
//===----------------------------------------------------------------------===//
// SourceFileInfo tracking...
//
/// getSourceFile - Return source file information for the specified source file
/// descriptor object, adding it to the collection as needed. This method
/// always succeeds (is unambiguous), and is always efficient.
///
const SourceFileInfo &
ProgramInfo::getSourceFile(const GlobalVariable *Desc) {
SourceFileInfo *&Result = SourceFiles[Desc];
if (Result) return *Result;
// Figure out what language this source file comes from...
unsigned LangID = 0; // Zero is unknown language
if (Desc && Desc->hasInitializer())
if (ConstantStruct *CS = dyn_cast<ConstantStruct>(Desc->getInitializer()))
if (CS->getNumOperands() > 2)
if (ConstantUInt *CUI = dyn_cast<ConstantUInt>(CS->getOperand(2)))
LangID = CUI->getValue();
const SourceLanguage &Lang = SourceLanguage::get(LangID);
SourceFileInfo *New = Lang.createSourceFileInfo(Desc, *this);
// FIXME: this should check to see if there is already a Filename/WorkingDir
// pair that matches this one. If so, we shouldn't create the duplicate!
//
SourceFileIndex.insert(std::make_pair(New->getBaseName(), New));
return *(Result = New);
}
/// getSourceFiles - Index all of the source files in the program and return
/// a mapping of it. This information is lazily computed the first time
/// that it is requested. Since this information can take a long time to
/// compute, the user is given a chance to cancel it. If this occurs, an
/// exception is thrown.
const std::map<const GlobalVariable*, SourceFileInfo*> &
ProgramInfo::getSourceFiles(bool RequiresCompleteMap) {
// If we have a fully populated map, or if the client doesn't need one, just
// return what we have.
if (SourceFilesIsComplete || !RequiresCompleteMap)
return SourceFiles;
// Ok, all of the source file descriptors (compile_unit in dwarf terms),
// should be on the use list of the llvm.dbg.translation_units global.
//
GlobalVariable *Units =
M->getGlobalVariable("llvm.dbg.translation_units",
StructType::get(std::vector<const Type*>()));
if (Units == 0)
throw "Program contains no debugging information!";
std::vector<GlobalVariable*> TranslationUnits;
getGlobalVariablesUsing(Units, TranslationUnits);
SlowOperationInformer SOI("building source files index");
// Loop over all of the translation units found, building the SourceFiles
// mapping.
for (unsigned i = 0, e = TranslationUnits.size(); i != e; ++i) {
getSourceFile(TranslationUnits[i]);
SOI.progress(i+1, e);
}
// Ok, if we got this far, then we indexed the whole program.
SourceFilesIsComplete = true;
return SourceFiles;
}
/// getSourceFile - Look up the file with the specified name. If there is
/// more than one match for the specified filename, prompt the user to pick
/// one. If there is no source file that matches the specified name, throw
/// an exception indicating that we can't find the file. Otherwise, return
/// the file information for that file.
const SourceFileInfo &ProgramInfo::getSourceFile(const std::string &Filename) {
std::multimap<std::string, SourceFileInfo*>::const_iterator Start, End;
getSourceFiles();
tie(Start, End) = SourceFileIndex.equal_range(Filename);
if (Start == End) throw "Could not find source file '" + Filename + "'!";
const SourceFileInfo &SFI = *Start->second;
++Start;
if (Start == End) return SFI;
throw "FIXME: Multiple source files with the same name not implemented!";
}
//===----------------------------------------------------------------------===//
// SourceFunctionInfo tracking...
//
/// getFunction - Return function information for the specified function
/// descriptor object, adding it to the collection as needed. This method
/// always succeeds (is unambiguous), and is always efficient.
///
const SourceFunctionInfo &
ProgramInfo::getFunction(const GlobalVariable *Desc) {
SourceFunctionInfo *&Result = SourceFunctions[Desc];
if (Result) return *Result;
// Figure out what language this function comes from...
const GlobalVariable *SourceFileDesc = 0;
if (Desc && Desc->hasInitializer())
if (ConstantStruct *CS = dyn_cast<ConstantStruct>(Desc->getInitializer()))
if (CS->getNumOperands() > 0)
if (const ConstantPointerRef *CPR =
dyn_cast<ConstantPointerRef>(CS->getOperand(1)))
SourceFileDesc = dyn_cast<GlobalVariable>(CPR->getValue());
const SourceLanguage &Lang = getSourceFile(SourceFileDesc).getLanguage();
return *(Result = Lang.createSourceFunctionInfo(Desc, *this));
}
// getSourceFunctions - Index all of the functions in the program and return
// them. This information is lazily computed the first time that it is
// requested. Since this information can take a long time to compute, the user
// is given a chance to cancel it. If this occurs, an exception is thrown.
const std::map<const GlobalVariable*, SourceFunctionInfo*> &
ProgramInfo::getSourceFunctions(bool RequiresCompleteMap) {
if (SourceFunctionsIsComplete || !RequiresCompleteMap)
return SourceFunctions;
// Ok, all of the source function descriptors (subprogram in dwarf terms),
// should be on the use list of the llvm.dbg.translation_units global.
//
GlobalVariable *Units =
M->getGlobalVariable("llvm.dbg.globals",
StructType::get(std::vector<const Type*>()));
if (Units == 0)
throw "Program contains no debugging information!";
std::vector<GlobalVariable*> Functions;
getGlobalVariablesUsing(Units, Functions);
SlowOperationInformer SOI("building functions index");
// Loop over all of the functions found, building the SourceFunctions mapping.
for (unsigned i = 0, e = Functions.size(); i != e; ++i) {
getFunction(Functions[i]);
SOI.progress(i+1, e);
}
// Ok, if we got this far, then we indexed the whole program.
SourceFunctionsIsComplete = true;
return SourceFunctions;
}

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//===-- llvm/lib/Debugger/ - LLVM Debugger interfaces ---------------------===//
This directory contains the implementation of the LLVM debugger backend. This
directory builds into a library which can be used by various debugger
front-ends to debug LLVM programs. The current command line LLVM debugger,
llvm-db is currently the only client of this library, but others could be
built, to provide a GUI front-end for example.

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//===-- RuntimeInfo.cpp - Compute and cache info about running program ----===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the RuntimeInfo and related classes, by querying and
// cachine information from the running inferior process.
//
//===----------------------------------------------------------------------===//
#include "llvm/Debugger/InferiorProcess.h"
#include "llvm/Debugger/ProgramInfo.h"
#include "llvm/Debugger/RuntimeInfo.h"
using namespace llvm;
//===----------------------------------------------------------------------===//
// StackFrame class implementation
StackFrame::StackFrame(RuntimeInfo &ri, void *ParentFrameID)
: RI(ri), SourceInfo(0) {
FrameID = RI.getInferiorProcess().getPreviousFrame(ParentFrameID);
if (FrameID == 0) throw "Stack frame does not exist!";
// Compute lazily as needed.
FunctionDesc = 0;
}
const GlobalVariable *StackFrame::getFunctionDesc() {
if (FunctionDesc == 0)
FunctionDesc = RI.getInferiorProcess().getSubprogramDesc(FrameID);
return FunctionDesc;
}
/// getSourceLocation - Return the source location that this stack frame is
/// sitting at.
void StackFrame::getSourceLocation(unsigned &lineNo, unsigned &colNo,
const SourceFileInfo *&sourceInfo) {
if (SourceInfo == 0) {
const GlobalVariable *SourceDesc = 0;
RI.getInferiorProcess().getFrameLocation(FrameID, LineNo,ColNo, SourceDesc);
SourceInfo = &RI.getProgramInfo().getSourceFile(SourceDesc);
}
lineNo = LineNo;
colNo = ColNo;
sourceInfo = SourceInfo;
}
//===----------------------------------------------------------------------===//
// RuntimeInfo class implementation
/// materializeFrame - Create and process all frames up to and including the
/// specified frame number. This throws an exception if the specified frame
/// ID is nonexistant.
void RuntimeInfo::materializeFrame(unsigned ID) {
assert(ID >= CallStack.size() && "no need to materialize this frame!");
void *CurFrame = 0;
if (!CallStack.empty())
CurFrame = CallStack.back().getFrameID();
while (CallStack.size() <= ID) {
CallStack.push_back(StackFrame(*this, CurFrame));
CurFrame = CallStack.back().getFrameID();
}
}

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//===-- SourceFile.cpp - SourceFile implementation for the debugger -------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the SourceFile class for the LLVM debugger.
//
//===----------------------------------------------------------------------===//
#include "llvm/Debugger/SourceFile.h"
#include "Support/SlowOperationInformer.h"
#include "Support/FileUtilities.h"
#include <iostream>
#include <cerrno>
#include <fcntl.h>
#include <unistd.h>
using namespace llvm;
/// readFile - Load Filename into FileStart and FileEnd.
///
void SourceFile::readFile() {
ssize_t FileSize = getFileSize(Filename);
if (FileSize != -1) {
FDHandle FD(open(Filename.c_str(), O_RDONLY));
if (FD != -1) {
char *FilePos = new char[FileSize];
FileStart = FilePos;
// If this takes a long time, inform the user what we are doing.
SlowOperationInformer SOI("loading source file '" + Filename + "'");
try {
// Read in the whole buffer.
unsigned Amount = FileSize;
while (Amount) {
unsigned AmountToRead = 512*1024;
if (Amount < AmountToRead) AmountToRead = Amount;
ssize_t ReadAmount = read(FD, FilePos, AmountToRead);
if (ReadAmount < 0 && errno == EINTR)
continue;
else if (ReadAmount <= 0) {
// Couldn't read whole file just free memory and continue.
throw "Error reading file '" + Filename + "'!";
}
Amount -= ReadAmount;
FilePos += ReadAmount;
SOI.progress(FileSize-Amount, FileSize);
}
} catch (const std::string &Msg) {
std::cout << Msg << "\n";
// If the user cancels the operation, clean up after ourselves.
delete [] FileStart;
FileStart = 0;
return;
}
FileEnd = FileStart+FileSize;
}
}
}
/// calculateLineOffsets - Compute the LineOffset vector for the current file.
///
void SourceFile::calculateLineOffsets() const {
assert(LineOffset.empty() && "Line offsets already computed!");
const char *BufPtr = FileStart;
do {
LineOffset.push_back(BufPtr-FileStart);
// Scan until we get to a newline.
while (BufPtr != FileEnd && *BufPtr != '\n' && *BufPtr != '\r')
++BufPtr;
if (BufPtr != FileEnd) {
++BufPtr; // Skip over the \n or \r
if (BufPtr[-1] == '\r' && BufPtr != FileEnd && BufPtr[0] == '\n')
++BufPtr; // Skip over dos/windows style \r\n's
}
} while (BufPtr != FileEnd);
}
/// getSourceLine - Given a line number, return the start and end of the line
/// in the file. If the line number is invalid, or if the file could not be
/// loaded, null pointers are returned for the start and end of the file. Note
/// that line numbers start with 0, not 1.
void SourceFile::getSourceLine(unsigned LineNo, const char *&LineStart,
const char *&LineEnd) const {
LineStart = LineEnd = 0;
if (FileStart == 0) return; // Couldn't load file, return null pointers
if (LineOffset.empty()) calculateLineOffsets();
// Asking for an out-of-range line number?
if (LineNo >= LineOffset.size()) return;
// Otherwise, they are asking for a valid line, which we can fulfill.
LineStart = FileStart+LineOffset[LineNo];
if (LineNo+1 < LineOffset.size())
LineEnd = FileStart+LineOffset[LineNo+1];
else
LineEnd = FileEnd;
// If the line ended with a newline, strip it off.
while (LineEnd != LineStart && (LineEnd[-1] == '\n' || LineEnd[-1] == '\r'))
--LineEnd;
assert(LineEnd >= LineStart && "We somehow got our pointers swizzled!");
}

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//===-- SourceLanguage-CFamily.cpp - C family SourceLanguage impl ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the SourceLanguage class for the C family of languages
// (K&R C, C89, C99, etc).
//
//===----------------------------------------------------------------------===//
#include "llvm/Debugger/SourceLanguage.h"
using namespace llvm;
#if 0
namespace {
struct CSL : public SourceLanguage {
} TheCSourceLanguageInstance;
}
#endif
const SourceLanguage &SourceLanguage::getCFamilyInstance() {
return get(0); // We don't have an implementation for C yet fall back on
// generic
}

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//===-- SourceLanguage-CPlusPlus.cpp - C++ SourceLanguage impl ------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the SourceLanguage class for the C++ language.
//
//===----------------------------------------------------------------------===//
#include "llvm/Debugger/SourceLanguage.h"
using namespace llvm;
#if 0
namespace {
struct CPPSL : public SourceLanguage {
} TheCPlusPlusLanguageInstance;
}
#endif
const SourceLanguage &SourceLanguage::getCPlusPlusInstance() {
return get(0); // We don't have an implementation for C yet fall back on
// generic
}

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//===-- SourceLanguage-Unknown.cpp - Implement itf for unknown languages --===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// If the LLVM debugger does not have a module for a particular language, it
// falls back on using this one to perform the source-language interface. This
// interface is not wonderful, but it gets the job done.
//
//===----------------------------------------------------------------------===//
#include "llvm/Debugger/SourceLanguage.h"
#include "llvm/Debugger/ProgramInfo.h"
#include <iostream>
using namespace llvm;
//===----------------------------------------------------------------------===//
// Implement the SourceLanguage cache for the Unknown language.
//
namespace {
/// SLUCache - This cache allows for efficient lookup of source functions by
/// name.
///
struct SLUCache : public SourceLanguageCache {
ProgramInfo &PI;
std::multimap<std::string, SourceFunctionInfo*> FunctionMap;
public:
SLUCache(ProgramInfo &pi);
typedef std::multimap<std::string, SourceFunctionInfo*>::const_iterator
fm_iterator;
std::pair<fm_iterator, fm_iterator>
getFunction(const std::string &Name) const {
return FunctionMap.equal_range(Name);
}
SourceFunctionInfo *addSourceFunction(SourceFunctionInfo *SF) {
FunctionMap.insert(std::make_pair(SF->getSymbolicName(), SF));
return SF;
}
};
}
SLUCache::SLUCache(ProgramInfo &pi) : PI(pi) {
}
//===----------------------------------------------------------------------===//
// Implement SourceLanguageUnknown class, which is used to handle unrecognized
// languages.
//
namespace {
struct SLU : public SourceLanguage {
//===------------------------------------------------------------------===//
// Implement the miscellaneous methods...
//
virtual const char *getSourceLanguageName() const {
return "unknown";
}
/// lookupFunction - Given a textual function name, return the
/// SourceFunctionInfo descriptor for that function, or null if it cannot be
/// found. If the program is currently running, the RuntimeInfo object
/// provides information about the current evaluation context, otherwise it
/// will be null.
///
virtual SourceFunctionInfo *lookupFunction(const std::string &FunctionName,
ProgramInfo &PI,
RuntimeInfo *RI = 0) const;
//===------------------------------------------------------------------===//
// We do use a cache for information...
//
typedef SLUCache CacheType;
SLUCache *createSourceLanguageCache(ProgramInfo &PI) const {
return new SLUCache(PI);
}
/// createSourceFunctionInfo - Create the new object and inform the cache of
/// the new function.
virtual SourceFunctionInfo *
createSourceFunctionInfo(const GlobalVariable *Desc, ProgramInfo &PI) const;
} TheUnknownSourceLanguageInstance;
}
const SourceLanguage &SourceLanguage::getUnknownLanguageInstance() {
return TheUnknownSourceLanguageInstance;
}
SourceFunctionInfo *
SLU::createSourceFunctionInfo(const GlobalVariable *Desc,
ProgramInfo &PI) const {
SourceFunctionInfo *Result = new SourceFunctionInfo(PI, Desc);
return PI.getLanguageCache(this).addSourceFunction(Result);
}
/// lookupFunction - Given a textual function name, return the
/// SourceFunctionInfo descriptor for that function, or null if it cannot be
/// found. If the program is currently running, the RuntimeInfo object
/// provides information about the current evaluation context, otherwise it will
/// be null.
///
SourceFunctionInfo *SLU::lookupFunction(const std::string &FunctionName,
ProgramInfo &PI, RuntimeInfo *RI) const{
SLUCache &Cache = PI.getLanguageCache(this);
std::pair<SLUCache::fm_iterator, SLUCache::fm_iterator> IP
= Cache.getFunction(FunctionName);
if (IP.first == IP.second) {
if (PI.allSourceFunctionsRead())
return 0; // Nothing found
// Otherwise, we might be able to find the function if we read all of them
// in. Do so now.
PI.getSourceFunctions();
assert(PI.allSourceFunctionsRead() && "Didn't read in all functions?");
return lookupFunction(FunctionName, PI, RI);
}
SourceFunctionInfo *Found = IP.first->second;
++IP.first;
if (IP.first != IP.second)
std::cout << "Whoa, found multiple functions with the same name. I should"
<< " ask the user which one to use: FIXME!\n";
return Found;
}

54
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//===-- SourceLanguage.cpp - Implement the SourceLanguage class -----------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the SourceLanguage class.
//
//===----------------------------------------------------------------------===//
#include "llvm/Debugger/SourceLanguage.h"
#include "llvm/Debugger/ProgramInfo.h"
using namespace llvm;
const SourceLanguage &SourceLanguage::get(unsigned ID) {
switch (ID) {
case 1: // DW_LANG_C89
case 2: // DW_LANG_C
case 12: // DW_LANG_C99
return getCFamilyInstance();
case 4: // DW_LANG_C_plus_plus
return getCPlusPlusInstance();
case 3: // DW_LANG_Ada83
case 5: // DW_LANG_Cobol74
case 6: // DW_LANG_Cobol85
case 7: // DW_LANG_Fortran77
case 8: // DW_LANG_Fortran90
case 9: // DW_LANG_Pascal83
case 10: // DW_LANG_Modula2
case 11: // DW_LANG_Java
case 13: // DW_LANG_Ada95
case 14: // DW_LANG_Fortran95
default:
return getUnknownLanguageInstance();
}
}
SourceFileInfo *
SourceLanguage::createSourceFileInfo(const GlobalVariable *Desc,
ProgramInfo &PI) const {
return new SourceFileInfo(Desc, *this);
}
SourceFunctionInfo *
SourceLanguage::createSourceFunctionInfo(const GlobalVariable *Desc,
ProgramInfo &PI) const {
return new SourceFunctionInfo(PI, Desc);
}

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//===-- UnixLocalInferiorProcess.cpp - A Local process on a Unixy system --===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file provides one implementation of the InferiorProcess class, which is
// designed to be used on unixy systems (those that support pipe, fork, exec,
// and signals).
//
// When the process is started, the debugger creates a pair of pipes, forks, and
// makes the child starts executing the program. The child executes the process
// with an IntrinsicLowering instance that turns debugger intrinsics into actual
// callbacks.
//
// This target takes advantage of the fact that the Module* addresses in the
// parent and the Module* addresses in the child will be the same, due to the
// use of fork(). As such, global addresses looked up in the child can be sent
// over the pipe to the debugger.
//
//===----------------------------------------------------------------------===//
#include "llvm/Debugger/InferiorProcess.h"
#include "llvm/IntrinsicLowering.h"
#include "llvm/Constant.h"
#include "llvm/Module.h"
#include "llvm/ModuleProvider.h"
#include "llvm/Type.h"
#include "llvm/iOther.h"
#include "llvm/ExecutionEngine/GenericValue.h"
#include "llvm/ExecutionEngine/ExecutionEngine.h"
#include "Support/FileUtilities.h"
#include "Support/StringExtras.h"
#include <cerrno>
#include <unistd.h> // Unix specific debugger support
#include <sys/types.h>
#include <sys/wait.h>
using namespace llvm;
// runChild - Entry point for the child process.
static void runChild(Module *M, const std::vector<std::string> &Arguments,
const char * const *envp,
FDHandle ReadFD, FDHandle WriteFD);
//===----------------------------------------------------------------------===//
// Parent/Child Pipe Protocol
//===----------------------------------------------------------------------===//
//
// The parent/child communication protocol is designed to have the child process
// responding to requests that the debugger makes. Whenever the child process
// has stopped (due to a break point, single stepping, etc), the child process
// enters a message processing loop, where it reads and responds to commands
// until the parent decides that it wants to continue execution in some way.
//
// Whenever the child process stops, it notifies the debugger by sending an
// character over the wire.
//
namespace {
/// LocationToken - Objects of this type are sent across the pipe from the
/// child to the parent to indicate where various stack frames are located.
struct LocationToken {
unsigned Line, Col;
const GlobalVariable *File;
LocationToken(unsigned L = 0, unsigned C = 0, const GlobalVariable *F = 0)
: Line(L), Col(C), File(F) {}
};
}
// Once the debugger process has received the LocationToken, it can make
// requests of the child by sending one of the following enum values followed by
// any data required by that command. The child responds with data appropriate
// to the command.
//
namespace {
/// CommandID - This enum defines all of the commands that the child process
/// can respond to. The actual expected data and responses are defined as the
/// enum values are defined.
///
enum CommandID {
//===------------------------------------------------------------------===//
// Execution commands - These are sent to the child to from the debugger to
// get it to do certain things.
//
// StepProgram: void->char - This command causes the program to continue
// execution, but stop as soon as it reaches another stoppoint.
StepProgram,
// FinishProgram: FrameDesc*->char - This command causes the program to
// continue execution until the specified function frame returns.
FinishProgram,
// ContProgram: void->char - This command causes the program to continue
// execution, stopping at some point in the future.
ContProgram,
// GetSubprogramDescriptor: FrameDesc*->GlobalValue* - This command returns
// the GlobalValue* descriptor object for the specified stack frame.
GetSubprogramDescriptor,
// GetParentFrame: FrameDesc*->FrameDesc* - This command returns the frame
// descriptor for the parent stack frame to the specified one, or null if
// there is none.
GetParentFrame,
// GetFrameLocation - FrameDesc*->LocationToken - This command returns the
// location that a particular stack frame is stopped at.
GetFrameLocation,
// AddBreakpoint - LocationToken->unsigned - This command instructs the
// target to install a breakpoint at the specified location.
AddBreakpoint,
// RemoveBreakpoint - unsigned->void - This command instructs the target to
// remove a breakpoint.
RemoveBreakpoint,
};
}
//===----------------------------------------------------------------------===//
// Parent Process Code
//===----------------------------------------------------------------------===//
namespace {
class IP : public InferiorProcess {
// ReadFD, WriteFD - The file descriptors to read/write to the inferior
// process.
FDHandle ReadFD, WriteFD;
// ChildPID - The unix PID of the child process we forked.
mutable pid_t ChildPID;
public:
IP(Module *M, const std::vector<std::string> &Arguments,
const char * const *envp);
~IP();
std::string getStatus() const;
/// Execution method implementations...
virtual void stepProgram();
virtual void finishProgram(void *Frame);
virtual void contProgram();
// Stack frame method implementations...
virtual void *getPreviousFrame(void *Frame) const;
virtual const GlobalVariable *getSubprogramDesc(void *Frame) const;
virtual void getFrameLocation(void *Frame, unsigned &LineNo,
unsigned &ColNo,
const GlobalVariable *&SourceDesc) const;
// Breakpoint implementation methods
virtual unsigned addBreakpoint(unsigned LineNo, unsigned ColNo,
const GlobalVariable *SourceDesc);
virtual void removeBreakpoint(unsigned ID);
private:
/// startChild - This starts up the child process, and initializes the
/// ChildPID member.
///
void startChild(Module *M, const std::vector<std::string> &Arguments,
const char * const *envp);
/// killChild - Kill or reap the child process. This throws the
/// InferiorProcessDead exception an exit code if the process had already
/// died, otherwise it just kills it and returns.
void killChild() const;
private:
// Methods for communicating with the child process. If the child exits or
// dies while attempting to communicate with it, ChildPID is set to zero and
// an exception is thrown.
/// readFromChild - Low-level primitive to read some data from the child,
/// throwing an exception if it dies.
void readFromChild(void *Buffer, unsigned Size) const;
/// writeToChild - Low-level primitive to send some data to the child
/// process, throwing an exception if the child died.
void writeToChild(void *Buffer, unsigned Size) const;
/// sendCommand - Send a command token and the request data to the child.
///
void sendCommand(CommandID Command, void *Data, unsigned Size) const;
/// waitForStop - This method waits for the child process to reach a stop
/// point.
void waitForStop();
};
}
// create - This is the factory method for the InferiorProcess class. Since
// there is currently only one subclass of InferiorProcess, we just define it
// here.
InferiorProcess *
InferiorProcess::create(Module *M, const std::vector<std::string> &Arguments,
const char * const *envp) {
return new IP(M, Arguments, envp);
}
/// IP constructor - Create some pipes, them fork a child process. The child
/// process should start execution of the debugged program, but stop at the
/// first available opportunity.
IP::IP(Module *M, const std::vector<std::string> &Arguments,
const char * const *envp)
: InferiorProcess(M) {
// Start the child running...
startChild(M, Arguments, envp);
// Okay, we created the program and it is off and running. Wait for it to
// stop now.
try {
waitForStop();
} catch (InferiorProcessDead &IPD) {
throw "Error waiting for the child process to stop. "
"It exited with status " + itostr(IPD.getExitCode());
}
}
IP::~IP() {
// If the child is still running, kill it.
if (!ChildPID) return;
killChild();
}
/// getStatus - Return information about the unix process being debugged.
///
std::string IP::getStatus() const {
if (ChildPID == 0)
return "Unix target. ERROR: child process appears to be dead!\n";
return "Unix target: PID #" + utostr((unsigned)ChildPID) + "\n";
}
/// startChild - This starts up the child process, and initializes the
/// ChildPID member.
///
void IP::startChild(Module *M, const std::vector<std::string> &Arguments,
const char * const *envp) {
// Create the pipes. Make sure to immediately assign the returned file
// descriptors to FDHandle's so they get destroyed if an exception is thrown.
int FDs[2];
if (pipe(FDs)) throw "Error creating a pipe!";
FDHandle ChildReadFD(FDs[0]);
WriteFD = FDs[1];
if (pipe(FDs)) throw "Error creating a pipe!";
ReadFD = FDs[0];
FDHandle ChildWriteFD(FDs[1]);
// Fork off the child process.
switch (ChildPID = fork()) {
case -1: throw "Error forking child process!";
case 0: // child
delete this; // Free parent pipe file descriptors
runChild(M, Arguments, envp, ChildReadFD, ChildWriteFD);
exit(1);
default: break;
}
}
/// sendCommand - Send a command token and the request data to the child.
///
void IP::sendCommand(CommandID Command, void *Data, unsigned Size) const {
writeToChild(&Command, sizeof(Command));
writeToChild(Data, Size);
}
/// stepProgram - Implement the 'step' command, continuing execution until
/// the next possible stop point.
void IP::stepProgram() {
sendCommand(StepProgram, 0, 0);
waitForStop();
}
/// finishProgram - Implement the 'finish' command, executing the program until
/// the current function returns to its caller.
void IP::finishProgram(void *Frame) {
sendCommand(FinishProgram, &Frame, sizeof(Frame));
waitForStop();
}
/// contProgram - Implement the 'cont' command, continuing execution until
/// a breakpoint is encountered.
void IP::contProgram() {
sendCommand(ContProgram, 0, 0);
waitForStop();
}
//===----------------------------------------------------------------------===//
// Stack manipulation methods
//
/// getPreviousFrame - Given the descriptor for the current stack frame,
/// return the descriptor for the caller frame. This returns null when it
/// runs out of frames.
void *IP::getPreviousFrame(void *Frame) const {
sendCommand(GetParentFrame, &Frame, sizeof(Frame));
readFromChild(&Frame, sizeof(Frame));
return Frame;
}
/// getSubprogramDesc - Return the subprogram descriptor for the current
/// stack frame.
const GlobalVariable *IP::getSubprogramDesc(void *Frame) const {
sendCommand(GetSubprogramDescriptor, &Frame, sizeof(Frame));
const GlobalVariable *Desc;
readFromChild(&Desc, sizeof(Desc));
return Desc;
}
/// getFrameLocation - This method returns the source location where each stack
/// frame is stopped.
void IP::getFrameLocation(void *Frame, unsigned &LineNo, unsigned &ColNo,
const GlobalVariable *&SourceDesc) const {
sendCommand(GetFrameLocation, &Frame, sizeof(Frame));
LocationToken Loc;
readFromChild(&Loc, sizeof(Loc));
LineNo = Loc.Line;
ColNo = Loc.Col;
SourceDesc = Loc.File;
}
//===----------------------------------------------------------------------===//
// Breakpoint manipulation methods
//
unsigned IP::addBreakpoint(unsigned LineNo, unsigned ColNo,
const GlobalVariable *SourceDesc) {
LocationToken Loc;
Loc.Line = LineNo;
Loc.Col = ColNo;
Loc.File = SourceDesc;
sendCommand(AddBreakpoint, &Loc, sizeof(Loc));
unsigned ID;
readFromChild(&ID, sizeof(ID));
return ID;
}
void IP::removeBreakpoint(unsigned ID) {
sendCommand(RemoveBreakpoint, &ID, sizeof(ID));
}
//===----------------------------------------------------------------------===//
// Methods for communication with the child process
//
// Methods for communicating with the child process. If the child exits or dies
// while attempting to communicate with it, ChildPID is set to zero and an
// exception is thrown.
//
/// readFromChild - Low-level primitive to read some data from the child,
/// throwing an exception if it dies.
void IP::readFromChild(void *Buffer, unsigned Size) const {
assert(ChildPID &&
"Child process died and still attempting to communicate with it!");
while (Size) {
ssize_t Amount = read(ReadFD, Buffer, Size);
if (Amount == 0) {
// If we cannot communicate with the process, kill it.
killChild();
// If killChild succeeded, then the process must have closed the pipe FD
// or something, because the child existed, but we cannot communicate with
// it.
throw InferiorProcessDead(-1);
} else if (Amount == -1) {
if (errno != EINTR) {
ChildPID = 0;
killChild();
throw "Error reading from child process!";
}
} else {
// We read a chunk.
Buffer = (char*)Buffer + Amount;
Size -= Amount;
}
}
}
/// writeToChild - Low-level primitive to send some data to the child
/// process, throwing an exception if the child died.
void IP::writeToChild(void *Buffer, unsigned Size) const {
while (Size) {
ssize_t Amount = write(WriteFD, Buffer, Size);
if (Amount < 0 && errno == EINTR) continue;
if (Amount <= 0) {
// If we cannot communicate with the process, kill it.
killChild();
// If killChild succeeded, then the process must have closed the pipe FD
// or something, because the child existed, but we cannot communicate with
// it.
throw InferiorProcessDead(-1);
} else {
// We wrote a chunk.
Buffer = (char*)Buffer + Amount;
Size -= Amount;
}
}
}
/// killChild - Kill or reap the child process. This throws the
/// InferiorProcessDead exception an exit code if the process had already
/// died, otherwise it just returns the exit code if it had to be killed.
void IP::killChild() const {
assert(ChildPID != 0 && "Child has already been reaped!");
int Status = 0;
int PID;
do {
PID = waitpid(ChildPID, &Status, WNOHANG);
} while (PID < 0 && errno == EINTR);
if (PID < 0) throw "Error waiting for child to exit!";
// If the child process was already dead, then it died unexpectedly.
if (PID) {
assert(PID == ChildPID && "Didn't reap child?");
ChildPID = 0; // Child has been reaped
if (WIFEXITED(Status))
throw InferiorProcessDead(WEXITSTATUS(Status));
else if (WIFSIGNALED(Status))
throw InferiorProcessDead(WTERMSIG(Status));
throw InferiorProcessDead(-1);
}
// Otherwise, the child exists and has not yet been killed.
if (kill(ChildPID, SIGKILL) < 0)
throw "Error killing child process!";
do {
PID = waitpid(ChildPID, 0, 0);
} while (PID < 0 && errno == EINTR);
if (PID <= 0) throw "Error waiting for child to exit!";
assert(PID == ChildPID && "Didn't reap child?");
}
/// waitForStop - This method waits for the child process to reach a stop
/// point. When it does, it fills in the CurLocation member and returns.
void IP::waitForStop() {
char Dummy;
readFromChild(&Dummy, sizeof(char));
}
//===----------------------------------------------------------------------===//
// Child Process Code
//===----------------------------------------------------------------------===//
namespace {
class SourceSubprogram;
/// SourceRegion - Instances of this class represent the regions that are
/// active in the program.
class SourceRegion {
/// Parent - A pointer to the region that encloses the current one.
SourceRegion *Parent;
/// CurSubprogram - The subprogram that contains this region. This allows
/// efficient stack traversals.
SourceSubprogram *CurSubprogram;
/// CurLine, CurCol, CurFile - The last location visited by this region.
/// This is used for getting the source location of callers in stack frames.
unsigned CurLine, CurCol;
void *CurFileDesc;
//std::vector<void*> ActiveObjects;
public:
SourceRegion(SourceRegion *p, SourceSubprogram *Subprogram = 0)
: Parent(p), CurSubprogram(Subprogram ? Subprogram : p->getSubprogram()) {
CurLine = 0; CurCol = 0;
CurFileDesc = 0;
}
virtual ~SourceRegion() {}
SourceRegion *getParent() const { return Parent; }
SourceSubprogram *getSubprogram() const { return CurSubprogram; }
void updateLocation(unsigned Line, unsigned Col, void *File) {
CurLine = Line;
CurCol = Col;
CurFileDesc = File;
}
/// Return a LocationToken for the place that this stack frame stopped or
/// called a sub-function.
LocationToken getLocation(ExecutionEngine *EE) {
LocationToken LT;
LT.Line = CurLine;
LT.Col = CurCol;
const GlobalValue *GV = EE->getGlobalValueAtAddress(CurFileDesc);
LT.File = dyn_cast_or_null<GlobalVariable>(GV);
return LT;
}
};
/// SourceSubprogram - This is a stack-frame that represents a source program.
///
class SourceSubprogram : public SourceRegion {
/// Desc - A pointer to the descriptor for the subprogram that this frame
/// represents.
void *Desc;
public:
SourceSubprogram(SourceRegion *P, void *desc)
: SourceRegion(P, this), Desc(desc) {}
void *getDescriptor() const { return Desc; }
};
/// Child class - This class contains all of the information and methods used
/// by the child side of the debugger. The single instance of this object is
/// pointed to by the "TheChild" global variable.
class Child {
/// M - The module for the program currently being debugged.
///
Module *M;
/// EE - The execution engine that we are using to run the program.
///
ExecutionEngine *EE;
/// ReadFD, WriteFD - The file descriptor handles for this side of the
/// debugger pipe.
FDHandle ReadFD, WriteFD;
/// RegionStack - A linked list of all of the regions dynamically active.
///
SourceRegion *RegionStack;
/// StopAtNextOpportunity - If this flag is set, the child process will stop
/// and report to the debugger at the next possible chance it gets.
volatile bool StopAtNextOpportunity;
/// StopWhenSubprogramReturns - If this is non-null, the debugger requests
/// that the program stops when the specified function frame is destroyed.
SourceSubprogram *StopWhenSubprogramReturns;
/// Breakpoints - This contains a list of active breakpoints and their IDs.
///
std::vector<std::pair<unsigned, LocationToken> > Breakpoints;
/// CurBreakpoint - The last assigned breakpoint.
///
unsigned CurBreakpoint;
public:
Child(Module *m, ExecutionEngine *ee, FDHandle &Read, FDHandle &Write)
: M(m), EE(ee), ReadFD(Read), WriteFD(Write),
RegionStack(0), CurBreakpoint(0) {
StopAtNextOpportunity = true;
StopWhenSubprogramReturns = 0;
}
/// writeToParent - Send the specified buffer of data to the debugger
/// process.
void writeToParent(const void *Buffer, unsigned Size);
/// readFromParent - Read the specified number of bytes from the parent.
///
void readFromParent(void *Buffer, unsigned Size);
/// childStopped - This method is called whenever the child has stopped
/// execution due to a breakpoint, step command, interruption, or whatever.
/// This stops the process, responds to any requests from the debugger, and
/// when commanded to, can continue execution by returning.
///
void childStopped();
/// startSubprogram - This method creates a new region for the subroutine
/// with the specified descriptor.
void startSubprogram(void *FuncDesc);
/// startRegion - This method initiates the creation of an anonymous region.
///
void startRegion();
/// endRegion - This method terminates the last active region.
///
void endRegion();
/// reachedLine - This method is automatically called by the program every
/// time it executes an llvm.dbg.stoppoint intrinsic. If the debugger wants
/// us to stop here, we do so, otherwise we continue execution.
void reachedLine(unsigned Line, unsigned Col, void *SourceDesc);
};
/// TheChild - The single instance of the Child class, which only gets created
/// in the child process.
Child *TheChild = 0;
} // end anonymous namespace
// writeToParent - Send the specified buffer of data to the debugger process.
void Child::writeToParent(const void *Buffer, unsigned Size) {
while (Size) {
ssize_t Amount = write(WriteFD, Buffer, Size);
if (Amount < 0 && errno == EINTR) continue;
if (Amount <= 0) {
write(2, "ERROR: Connection to debugger lost!\n", 36);
abort();
} else {
// We wrote a chunk.
Buffer = (const char*)Buffer + Amount;
Size -= Amount;
}
}
}
// readFromParent - Read the specified number of bytes from the parent.
void Child::readFromParent(void *Buffer, unsigned Size) {
while (Size) {
ssize_t Amount = read(ReadFD, Buffer, Size);
if (Amount < 0 && errno == EINTR) continue;
if (Amount <= 0) {
write(2, "ERROR: Connection to debugger lost!\n", 36);
abort();
} else {
// We read a chunk.
Buffer = (char*)Buffer + Amount;
Size -= Amount;
}
}
}
/// childStopped - This method is called whenever the child has stopped
/// execution due to a breakpoint, step command, interruption, or whatever.
/// This stops the process, responds to any requests from the debugger, and when
/// commanded to, can continue execution by returning.
///
void Child::childStopped() {
// Since we stopped, notify the parent that we did so.
char Token = 0;
writeToParent(&Token, sizeof(char));
StopAtNextOpportunity = false;
StopWhenSubprogramReturns = 0;
// Now that the debugger knows that we stopped, read commands from it and
// respond to them appropriately.
CommandID Command;
while (1) {
SourceRegion *Frame;
const void *Result;
readFromParent(&Command, sizeof(CommandID));
switch (Command) {
case StepProgram:
// To step the program, just return.
StopAtNextOpportunity = true;
return;
case FinishProgram: // Run until exit from the specified function...
readFromParent(&Frame, sizeof(Frame));
// The user wants us to stop when the specified FUNCTION exits, not when
// the specified REGION exits.
StopWhenSubprogramReturns = Frame->getSubprogram();
return;
case ContProgram:
// To continue, just return back to execution.
return;
case GetSubprogramDescriptor:
readFromParent(&Frame, sizeof(Frame));
Result =
EE->getGlobalValueAtAddress(Frame->getSubprogram()->getDescriptor());
writeToParent(&Result, sizeof(Result));
break;
case GetParentFrame:
readFromParent(&Frame, sizeof(Frame));
Result = Frame ? Frame->getSubprogram()->getParent() : RegionStack;
writeToParent(&Result, sizeof(Result));
break;
case GetFrameLocation: {
readFromParent(&Frame, sizeof(Frame));
LocationToken LT = Frame->getLocation(EE);
writeToParent(&LT, sizeof(LT));
break;
}
case AddBreakpoint: {
LocationToken Loc;
readFromParent(&Loc, sizeof(Loc));
// Convert the GlobalVariable pointer to the address it was emitted to.
Loc.File = (GlobalVariable*)EE->getPointerToGlobal(Loc.File);
unsigned ID = CurBreakpoint++;
Breakpoints.push_back(std::make_pair(ID, Loc));
writeToParent(&ID, sizeof(ID));
break;
}
case RemoveBreakpoint: {
unsigned ID = 0;
readFromParent(&ID, sizeof(ID));
for (unsigned i = 0, e = Breakpoints.size(); i != e; ++i)
if (Breakpoints[i].first == ID) {
Breakpoints.erase(Breakpoints.begin()+i);
break;
}
break;
}
default:
assert(0 && "Unknown command!");
}
}
}
/// startSubprogram - This method creates a new region for the subroutine
/// with the specified descriptor.
void Child::startSubprogram(void *SPDesc) {
RegionStack = new SourceSubprogram(RegionStack, SPDesc);
}
/// startRegion - This method initiates the creation of an anonymous region.
///
void Child::startRegion() {
RegionStack = new SourceRegion(RegionStack);
}
/// endRegion - This method terminates the last active region.
///
void Child::endRegion() {
SourceRegion *R = RegionStack->getParent();
// If the debugger wants us to stop when this frame is destroyed, do so.
if (RegionStack == StopWhenSubprogramReturns) {
StopAtNextOpportunity = true;
StopWhenSubprogramReturns = 0;
}
delete RegionStack;
RegionStack = R;
}
/// reachedLine - This method is automatically called by the program every time
/// it executes an llvm.dbg.stoppoint intrinsic. If the debugger wants us to
/// stop here, we do so, otherwise we continue execution. Note that the Data
/// pointer coming in is a pointer to the LLVM global variable that represents
/// the source file we are in. We do not use the contents of the global
/// directly in the child, but we do use its address.
///
void Child::reachedLine(unsigned Line, unsigned Col, void *SourceDesc) {
if (RegionStack)
RegionStack->updateLocation(Line, Col, SourceDesc);
// If we hit a breakpoint, stop the program.
for (unsigned i = 0, e = Breakpoints.size(); i != e; ++i)
if (Line == Breakpoints[i].second.Line &&
SourceDesc == (void*)Breakpoints[i].second.File &&
Col == Breakpoints[i].second.Col) {
childStopped();
return;
}
// If we are single stepping the program, make sure to stop it.
if (StopAtNextOpportunity)
childStopped();
}
//===----------------------------------------------------------------------===//
// Child class wrapper functions
//
// These functions are invoked directly by the program as it executes, in place
// of the debugging intrinsic functions that it contains.
//
/// llvm_debugger_stop - Every time the program reaches a new source line, it
/// will call back to this function. If the debugger has a breakpoint or
/// otherwise wants us to stop on this line, we do so, and notify the debugger
/// over the pipe.
///
extern "C"
void *llvm_debugger_stop(void *Dummy, unsigned Line, unsigned Col,
void *SourceDescriptor) {
TheChild->reachedLine(Line, Col, SourceDescriptor);
return Dummy;
}
/// llvm_dbg_region_start - This function is invoked every time an anonymous
/// region of the source program is entered.
///
extern "C"
void *llvm_dbg_region_start(void *Dummy) {
TheChild->startRegion();
return Dummy;
}
/// llvm_dbg_subprogram - This function is invoked every time a source-language
/// subprogram has been entered.
///
extern "C"
void *llvm_dbg_subprogram(void *FuncDesc) {
TheChild->startSubprogram(FuncDesc);
return 0;
}
/// llvm_dbg_region_end - This function is invoked every time a source-language
/// region (started with llvm.dbg.region.start or llvm.dbg.func.start) is
/// terminated.
///
extern "C"
void llvm_dbg_region_end(void *Dummy) {
TheChild->endRegion();
}
namespace {
/// DebuggerIntrinsicLowering - This class implements a simple intrinsic
/// lowering class that revectors debugging intrinsics to call actual
/// functions (defined above), instead of being turned into noops.
struct DebuggerIntrinsicLowering : public DefaultIntrinsicLowering {
virtual void LowerIntrinsicCall(CallInst *CI) {
Module *M = CI->getParent()->getParent()->getParent();
switch (CI->getCalledFunction()->getIntrinsicID()) {
case Intrinsic::dbg_stoppoint:
// Turn call into a call to llvm_debugger_stop
CI->setOperand(0, M->getOrInsertFunction("llvm_debugger_stop",
CI->getCalledFunction()->getFunctionType()));
break;
case Intrinsic::dbg_region_start:
// Turn call into a call to llvm_dbg_region_start
CI->setOperand(0, M->getOrInsertFunction("llvm_dbg_region_start",
CI->getCalledFunction()->getFunctionType()));
break;
case Intrinsic::dbg_region_end:
// Turn call into a call to llvm_debugger_stop
CI->setOperand(0, M->getOrInsertFunction("llvm_dbg_region_end",
CI->getCalledFunction()->getFunctionType()));
break;
case Intrinsic::dbg_func_start:
// Turn call into a call to llvm_debugger_stop
CI->setOperand(0, M->getOrInsertFunction("llvm_dbg_subprogram",
CI->getCalledFunction()->getFunctionType()));
break;
default:
DefaultIntrinsicLowering::LowerIntrinsicCall(CI);
break;
}
}
};
} // end anonymous namespace
static void runChild(Module *M, const std::vector<std::string> &Arguments,
const char * const *envp,
FDHandle ReadFD, FDHandle WriteFD) {
// Create an execution engine that uses our custom intrinsic lowering object
// to revector debugging intrinsic functions into actual functions defined
// above.
ExecutionEngine *EE =
ExecutionEngine::create(new ExistingModuleProvider(M), false,
new DebuggerIntrinsicLowering());
assert(EE && "Couldn't create an ExecutionEngine, not even an interpreter?");
// Call the main function from M as if its signature were:
// int main (int argc, char **argv, const char **envp)
// using the contents of Args to determine argc & argv, and the contents of
// EnvVars to determine envp.
//
Function *Fn = M->getMainFunction();
if (!Fn) exit(1);
// Create the child class instance which will be used by the debugger
// callbacks to keep track of the current state of the process.
assert(TheChild == 0 && "A child process has already been created??");
TheChild = new Child(M, EE, ReadFD, WriteFD);
// Run main...
int Result = EE->runFunctionAsMain(Fn, Arguments, envp);
// If the program didn't explicitly call exit, call exit now, for the program.
// This ensures that any atexit handlers get called correctly.
Function *Exit = M->getOrInsertFunction("exit", Type::VoidTy, Type::IntTy, 0);
std::vector<GenericValue> Args;
GenericValue ResultGV;
ResultGV.IntVal = Result;
Args.push_back(ResultGV);
EE->runFunction(Exit, Args);
abort();
}