Fixes to breakpoint handling

Make sure stepping works correctly, and we always
break at a valid breakpoint.

Change-Id: I6a3032b3ae204484b8a92b2031904a7f681c7f80
Reviewed-by: Simon Hausmann <[email protected]>

4 files changed, 42 insertions, 37 deletions

diff --git a/src/qml/compiler/qv4isel_moth.cpp b/src/qml/compiler/qv4isel_moth.cpp
index 3993bc9acc..921af76151 100644
--- a/src/qml/compiler/qv4isel_moth.cpp
+++ b/src/qml/compiler/qv4isel_moth.cpp
@@ -385,8 +385,9 @@ void InstructionSelection::run(int functionIndex)
     push.value = quint32(locals);
     addInstruction(push);
 
-    uint currentLine = -1;
+    currentLine = -1;
     for (int i = 0, ei = _function->basicBlocks.size(); i != ei; ++i) {
+        blockNeedsDebugInstruction = irModule->debugMode;
         _block = _function->basicBlocks[i];
         _nextBlock = (i < ei - 1) ? _function->basicBlocks[i + 1] : 0;
         _addrs.insert(_block, _codeNext - _codeStart);
@@ -408,6 +409,7 @@ void InstructionSelection::run(int functionIndex)
 
             if (s->location.isValid()) {
                 if (s->location.startLine != currentLine) {
+                    blockNeedsDebugInstruction = false;
                     currentLine = s->location.startLine;
                     if (irModule->debugMode) {
                         Instruction::Debug debug;
@@ -423,11 +425,6 @@ void InstructionSelection::run(int functionIndex)
 
             s->accept(this);
         }
-        if (irModule->debugMode) {
-            Instruction::Debug debug;
-            debug.lineNumber = currentLine;
-            addInstruction(debug);
-        }
     }
 
     // TODO: patch stack size (the push instruction)
@@ -1039,6 +1036,12 @@ void InstructionSelection::visitJump(IR::Jump *s)
     if (_removableJumps.contains(s))
         return;
 
+    if (blockNeedsDebugInstruction) {
+        Instruction::Debug debug;
+        debug.lineNumber = currentLine;
+        addInstruction(debug);
+    }
+
     Instruction::Jump jump;
     jump.offset = 0;
     ptrdiff_t loc = addInstruction(jump) + (((const char *)&jump.offset) - ((const char *)&jump));
@@ -1048,6 +1051,12 @@ void InstructionSelection::visitJump(IR::Jump *s)
 
 void InstructionSelection::visitCJump(IR::CJump *s)
 {
+    if (blockNeedsDebugInstruction) {
+        Instruction::Debug debug;
+        debug.lineNumber = currentLine;
+        addInstruction(debug);
+    }
+
     Param condition;
     if (IR::Temp *t = s->cond->asTemp()) {
         condition = getResultParam(t);
diff --git a/src/qml/compiler/qv4isel_moth_p.h b/src/qml/compiler/qv4isel_moth_p.h
index 000ff634e7..4c01434156 100644
--- a/src/qml/compiler/qv4isel_moth_p.h
+++ b/src/qml/compiler/qv4isel_moth_p.h
@@ -169,6 +169,8 @@ private:
 
     QQmlEnginePrivate *qmlEngine;
 
+    bool blockNeedsDebugInstruction;
+    uint currentLine;
     IR::BasicBlock *_block;
     IR::BasicBlock *_nextBlock;
 
diff --git a/src/qml/jsruntime/qv4debugging.cpp b/src/qml/jsruntime/qv4debugging.cpp
index 92273417a9..04489903c3 100644
--- a/src/qml/jsruntime/qv4debugging.cpp
+++ b/src/qml/jsruntime/qv4debugging.cpp
@@ -113,12 +113,12 @@ public:
 
 Debugger::Debugger(QV4::ExecutionEngine *engine)
     : m_engine(engine)
+    , m_currentContext(0)
     , m_agent(0)
     , m_state(Running)
     , m_stepping(NotStepping)
     , m_pauseRequested(false)
     , m_haveBreakPoints(false)
-    , m_stopForStepping(false)
     , m_breakOnThrow(false)
     , m_returnedValue(Primitive::undefinedValue())
     , m_gatherSources(0)
@@ -180,6 +180,7 @@ void Debugger::resume(Speed speed)
     if (!m_returnedValue.isUndefined())
         m_returnedValue = Encode::undefined();
 
+    m_currentContext = m_engine->currentContext();
     m_stepping = speed;
     m_runningCondition.wakeAll();
 }
@@ -187,14 +188,14 @@ void Debugger::resume(Speed speed)
 void Debugger::addBreakPoint(const QString &fileName, int lineNumber, const QString &condition)
 {
     QMutexLocker locker(&m_lock);
-    m_breakPoints.insert(DebuggerBreakPoint(fileName, lineNumber), condition);
+    m_breakPoints.insert(DebuggerBreakPoint(fileName.mid(fileName.lastIndexOf('/') + 1), lineNumber), condition);
     m_haveBreakPoints = true;
 }
 
 void Debugger::removeBreakPoint(const QString &fileName, int lineNumber)
 {
     QMutexLocker locker(&m_lock);
-    m_breakPoints.remove(DebuggerBreakPoint(fileName, lineNumber));
+    m_breakPoints.remove(DebuggerBreakPoint(fileName.mid(fileName.lastIndexOf('/') + 1), lineNumber));
     m_haveBreakPoints = !m_breakPoints.isEmpty();
 }
 
@@ -207,10 +208,8 @@ void Debugger::setBreakOnThrow(bool onoff)
 
 Debugger::ExecutionState Debugger::currentExecutionState() const
 {
-    // ### Locking
     ExecutionState state;
-    state.function = getFunction();
-    state.fileName = state.function->sourceFile();
+    state.fileName = getFunction()->sourceFile();
     state.lineNumber = engine()->currentContext()->lineNumber;
 
     return state;
@@ -451,10 +450,7 @@ void Debugger::maybeBreakAtInstruction()
         return;
 
     QMutexLocker locker(&m_lock);
-    if (m_breakPoints.isEmpty())
-        return;
-
-    ExecutionState state = currentExecutionState();
+    int lineNumber = engine()->currentContext()->lineNumber;
 
     if (m_gatherSources) {
         m_gatherSources->run();
@@ -464,20 +460,22 @@ void Debugger::maybeBreakAtInstruction()
 
     switch (m_stepping) {
     case StepOver:
+        if (m_currentContext != m_engine->currentContext())
+            break;
+        // fall through
     case StepIn:
         pauseAndWait(Step);
-        break;
+        return;
     case StepOut:
     case NotStepping:
-        if (m_stopForStepping) { // Serve debugging requests from the agent
-            m_stopForStepping = false;
-            pauseAndWait(Step);
-        } else if (m_pauseRequested) { // Serve debugging requests from the agent
-            m_pauseRequested = false;
-            pauseAndWait(PauseRequest);
-        } else if (reallyHitTheBreakPoint(state.fileName, state.lineNumber)) {
-            pauseAndWait(BreakPoint);
-        }
+        break;
+    }
+
+    if (m_pauseRequested) { // Serve debugging requests from the agent
+        m_pauseRequested = false;
+        pauseAndWait(PauseRequest);
+    } else if (m_haveBreakPoints && reallyHitTheBreakPoint(getFunction()->sourceFile(), lineNumber)) {
+        pauseAndWait(BreakPoint);
     }
 }
 
@@ -486,8 +484,7 @@ void Debugger::enteringFunction()
     QMutexLocker locker(&m_lock);
 
     if (m_stepping == StepIn) {
-        m_stepping = NotStepping;
-        m_stopForStepping = true;
+        m_currentContext = m_engine->currentContext();
     }
 }
 
@@ -497,9 +494,9 @@ void Debugger::leavingFunction(const ReturnedValue &retVal)
 
     QMutexLocker locker(&m_lock);
 
-    if (m_stepping == StepOut || m_stepping == StepOver) {
-        m_stepping = NotStepping;
-        m_stopForStepping = true;
+    if (m_stepping != NotStepping && m_currentContext == m_engine->currentContext()) {
+        m_currentContext = m_engine->currentContext()->parent;
+        m_stepping = StepOver;
         m_returnedValue = retVal;
     }
 }
@@ -552,7 +549,7 @@ void Debugger::pauseAndWait(PauseReason reason)
 
 bool Debugger::reallyHitTheBreakPoint(const QString &filename, int linenr)
 {
-    BreakPoints::iterator it = m_breakPoints.find(DebuggerBreakPoint(filename, linenr));
+    BreakPoints::iterator it = m_breakPoints.find(DebuggerBreakPoint(filename.mid(filename.lastIndexOf('/') + 1), linenr));
     if (it == m_breakPoints.end())
         return false;
     QString condition = it.value();
diff --git a/src/qml/jsruntime/qv4debugging_p.h b/src/qml/jsruntime/qv4debugging_p.h
index 9c97dd5f9e..47a7d77b28 100644
--- a/src/qml/jsruntime/qv4debugging_p.h
+++ b/src/qml/jsruntime/qv4debugging_p.h
@@ -161,14 +161,12 @@ public:
 
     void setBreakOnThrow(bool onoff);
 
+    // used for testing
     struct ExecutionState
     {
-        ExecutionState() : lineNumber(-1), function(0) {}
         QString fileName;
         int lineNumber;
-        Function *function;
     };
-
     ExecutionState currentExecutionState() const;
 
     bool pauseAtNextOpportunity() const {
@@ -203,8 +201,8 @@ private:
     void runInEngine_havingLock(Debugger::Job *job);
 
 private:
-
     QV4::ExecutionEngine *m_engine;
+    QV4::ExecutionContext *m_currentContext;
     DebuggerAgent *m_agent;
     QMutex m_lock;
     QWaitCondition m_runningCondition;
@@ -212,7 +210,6 @@ private:
     Speed m_stepping;
     bool m_pauseRequested;
     bool m_haveBreakPoints;
-    bool m_stopForStepping;
     bool m_breakOnThrow;
 
     BreakPoints m_breakPoints;