Change the interpreter's stack frame to be allocated with alloca.

Change-Id: Ia02ad1af3bb0f429a6078029bf7aaee5a17f3413
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

4 files changed, 5 insertions, 149 deletions

diff --git a/moth/moth.pri b/moth/moth.pri
index 160c1aac00..73bd893286 100644
--- a/moth/moth.pri
+++ b/moth/moth.pri
@@ -3,13 +3,11 @@ INCLUDEPATH += $$PWD
 HEADERS += \
     $$PWD/qv4isel_moth_p.h \
     $$PWD/qv4instr_moth_p.h \
-    $$PWD/qv4vme_moth_p.h \
-    $$PWD/qv4mm_moth.h
+    $$PWD/qv4vme_moth_p.h
 
 SOURCES += \
     $$PWD/qv4isel_moth.cpp \
     $$PWD/qv4instr_moth.cpp \
-    $$PWD/qv4vme_moth.cpp \
-    $$PWD/qv4mm_moth.cpp
+    $$PWD/qv4vme_moth.cpp
 
 #DEFINES += DO_TRACE_INSTR
diff --git a/moth/qv4mm_moth.cpp b/moth/qv4mm_moth.cpp
deleted file mode 100644
index 44e45fe027..0000000000
--- a/moth/qv4mm_moth.cpp
+++ /dev/null
@@ -1,81 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
-** Contact: http://www.qt-project.org/legal
-**
-** This file is part of Qt Creator.
-**
-** Commercial License Usage
-** Licensees holding valid commercial Qt licenses may use this file in
-** accordance with the commercial license agreement provided with the
-** Software or, alternatively, in accordance with the terms contained in
-** a written agreement between you and Digia.  For licensing terms and
-** conditions see http://qt.digia.com/licensing.  For further information
-** use the contact form at http://qt.digia.com/contact-us.
-**
-** GNU Lesser General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU Lesser
-** General Public License version 2.1 as published by the Free Software
-** Foundation and appearing in the file LICENSE.LGPL included in the
-** packaging of this file.  Please review the following information to
-** ensure the GNU Lesser General Public License version 2.1 requirements
-** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
-**
-** In addition, as a special exception, Digia gives you certain additional
-** rights.  These rights are described in the Digia Qt LGPL Exception
-** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
-**
-****************************************************************************/
-
-#include "qmljs_engine.h"
-#include "qv4mm_moth.h"
-
-#include <QList>
-
-using namespace QQmlJS;
-using namespace QQmlJS::Moth;
-
-MemoryManager::MemoryManager()
-{
-    stackFrames.reserve(64);
-}
-
-MemoryManager::~MemoryManager()
-{
-}
-
-VM::Value *MemoryManager::allocStackFrame(std::size_t frameSize)
-{
-    std::size_t size = frameSize * sizeof(VM::Value);
-    MMObject *m = alloc(align(size));
-    stackFrames.append(m);
-    return reinterpret_cast<VM::Value *>(&m->data);
-}
-
-void MemoryManager::deallocStackFrame(VM::Value *stackFrame)
-{
-    MMObject *o = toObject(stackFrame);
-    for (int i = stackFrames.size() - 1; i >= 0; --i) {
-        if (stackFrames[i] == o) {
-            stackFrames.remove(i);
-            dealloc(o);
-            return;
-        }
-    }
-
-    Q_UNREACHABLE();
-}
-
-void MemoryManager::collectRootsOnStack(QVector<VM::Object *> &roots) const
-{
-    for (int i = 0, ei = stackFrames.size(); i < ei; ++i) {
-        MMObject *m = stackFrames[i];
-        VM::Value *frame = reinterpret_cast<VM::Value *>(&m->data);
-        std::size_t frameSize = (m->info.size - align(sizeof(MMInfo))) / sizeof(VM::Value);
-        for (std::size_t j = 0; j < frameSize; ++j) {
-            if (VM::Object *o = frame[j].asObject()) {
-                roots.append(o);
-            }
-        }
-    }
-}
diff --git a/moth/qv4mm_moth.h b/moth/qv4mm_moth.h
deleted file mode 100644
index a2b1ebd556..0000000000
--- a/moth/qv4mm_moth.h
+++ /dev/null
@@ -1,59 +0,0 @@
-/****************************************************************************
-**
-** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
-** Contact: http://www.qt-project.org/legal
-**
-** This file is part of Qt Creator.
-**
-** Commercial License Usage
-** Licensees holding valid commercial Qt licenses may use this file in
-** accordance with the commercial license agreement provided with the
-** Software or, alternatively, in accordance with the terms contained in
-** a written agreement between you and Digia.  For licensing terms and
-** conditions see http://qt.digia.com/licensing.  For further information
-** use the contact form at http://qt.digia.com/contact-us.
-**
-** GNU Lesser General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU Lesser
-** General Public License version 2.1 as published by the Free Software
-** Foundation and appearing in the file LICENSE.LGPL included in the
-** packaging of this file.  Please review the following information to
-** ensure the GNU Lesser General Public License version 2.1 requirements
-** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
-**
-** In addition, as a special exception, Digia gives you certain additional
-** rights.  These rights are described in the Digia Qt LGPL Exception
-** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
-**
-****************************************************************************/
-
-#ifndef QV4GC_MOTH_H
-#define QV4GC_MOTH_H
-
-#include "qv4mm.h"
-
-#include <QVector>
-
-namespace QQmlJS {
-namespace Moth {
-
-class MemoryManager: public QQmlJS::VM::MemoryManager
-{
-public:
-    MemoryManager();
-    ~MemoryManager();
-
-    VM::Value *allocStackFrame(std::size_t frameSize);
-    void deallocStackFrame(VM::Value *stackFrame);
-
-protected:
-    virtual void collectRootsOnStack(QVector<VM::Object *> &roots) const;
-
-private:
-    QVector<MMObject *> stackFrames;
-};
-
-} // namespace Moth
-} // namespace QQmlJS
-
-#endif // QV4GC_MOTH_H
diff --git a/moth/qv4vme_moth.cpp b/moth/qv4vme_moth.cpp
index 2a1302f423..0156e4a8da 100644
--- a/moth/qv4vme_moth.cpp
+++ b/moth/qv4vme_moth.cpp
@@ -2,10 +2,11 @@
 #include "qv4instr_moth_p.h"
 #include "qmljs_value.h"
 #include "debugging.h"
-#include "qv4mm_moth.h"
 
 #include <iostream>
 
+#include <alloca.h>
+
 #ifdef DO_TRACE_INSTR
 #  define TRACE_INSTR(I) fprintf(stderr, "executing a %s\n", #I);
 #  define TRACE(n, str, ...) { char buf[4096]; snprintf(buf, 4096, str, __VA_ARGS__); fprintf(stderr, "    %s : %s\n", #n, buf); }
@@ -103,9 +104,6 @@ public:
         , code(code)
     {}
 
-    ~FunctionState()
-    { if (stack) static_cast<MemoryManager *>(context()->engine->memoryManager)->deallocStackFrame(stack); }
-
     virtual VM::Value *temp(unsigned idx) { return stack + idx; }
 
     void setStack(VM::Value *stack, unsigned stackSize)
@@ -201,7 +199,7 @@ VM::Value VME::operator()(QQmlJS::VM::ExecutionContext *context, const uchar *co
     MOTH_BEGIN_INSTR(Push)
         TRACE(inline, "stack size: %u", instr.value);
         stackSize = instr.value;
-        stack = static_cast<MemoryManager *>(context->engine->memoryManager)->allocStackFrame(stackSize);
+        stack = static_cast<VM::Value *>(alloca(stackSize * sizeof(VM::Value)));
         state.setStack(stack, stackSize);
     MOTH_END_INSTR(Push)