Simple assembler moved to separate class which is independent on Qt GUI API.

Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>

10 files changed, 420 insertions, 213 deletions

diff --git a/qtmips_asm/qtmips_asm.pro b/qtmips_asm/qtmips_asm.pro
index d096961..ed42c10 100644
--- a/qtmips_asm/qtmips_asm.pro
+++ b/qtmips_asm/qtmips_asm.pro
@@ -6,6 +6,9 @@ CONFIG += c++11
 TEMPLATE = lib
 CONFIG += staticlib
 
+INCLUDEPATH += $$PWD/../qtmips_machine $$PWD/../qtmips_osemu
+DEPENDPATH += $$PWD/../qtmips_machine
+
 LIBS += -lelf
 QMAKE_CXXFLAGS += -std=c++0x
 QMAKE_CXXFLAGS_DEBUG += -ggdb
@@ -14,8 +17,10 @@ DEFINES += QTMIPS_MACHINE_LIBRARY
 DEFINES += QT_DEPRECATED_WARNINGS
 
 SOURCES += \
-    fixmatheval.cpp
+    fixmatheval.cpp \
+    simpleasm.cpp
 
 HEADERS += \
     fixmatheval.h \
-    messagetype.h
+    messagetype.h \
+    simpleasm.h
diff --git a/qtmips_asm/simpleasm.cpp b/qtmips_asm/simpleasm.cpp
new file mode 100644
index 0000000..15d50b2
--- /dev/null
+++ b/qtmips_asm/simpleasm.cpp
@@ -0,0 +1,285 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*******************************************************************************
+ * QtMips - MIPS 32-bit Architecture Subset Simulator
+ *
+ * Implemented to support following courses:
+ *
+ *   B35APO - Computer Architectures
+ *   https://cw.fel.cvut.cz/wiki/courses/b35apo
+ *
+ *   B4M35PAP - Advanced Computer Architectures
+ *   https://cw.fel.cvut.cz/wiki/courses/b4m35pap/start
+ *
+ * Copyright (c) 2017-2019 Karel Koci<cynerd@email.cz>
+ * Copyright (c) 2019      Pavel Pisa <pisa@cmp.felk.cvut.cz>
+ *
+ * Faculty of Electrical Engineering (http://www.fel.cvut.cz)
+ * Czech Technical University        (http://www.cvut.cz/)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA  02110-1301, USA.
+ *
+ ******************************************************************************/
+
+#include <QObject>
+
+#include "simpleasm.h"
+
+using namespace fixmatheval;
+
+
+SymbolTableDb::SymbolTableDb(machine::SymbolTable *symtab) {
+    this->symtab = symtab;
+}
+
+bool SymbolTableDb::getValue(fixmatheval::FmeValue &value, QString name) {
+    std::uint32_t val;
+    if (!symtab->name_to_value(val, name))
+        return false;
+    value = val;
+    return true;
+}
+
+void SymbolTableDb::setSymbol(QString name, std::uint32_t value, std::uint32_t size,
+          unsigned char info, unsigned char other) {
+    symtab->set_symbol(name, value, size, info, other);
+}
+
+
+std::uint64_t SimpleAsm::string_to_uint64(QString str, int base,
+                                      int *chars_taken) {
+    int i;
+    std::int64_t val;
+    char *p, *r;
+    char cstr[str.count() + 1];
+    for (i = 0; i < str.count(); i++)
+        cstr[i] = str.at(i).toLatin1();
+    cstr[i] = 0;
+    p = cstr;
+    val = std::strtoll(p, &r, base);
+    if (chars_taken != nullptr)
+        *chars_taken = r - p;
+    return val;
+}
+
+SimpleAsm::SimpleAsm(QObject *parent) : Super(parent) {
+    clear();
+}
+
+SimpleAsm::~SimpleAsm() {
+    clear();
+}
+
+void SimpleAsm::clear() {
+    symtab = nullptr;
+    mem = nullptr;
+    while (!reloc.isEmpty()) {
+        delete reloc.takeFirst();
+    }
+    error_occured = false;
+    fatal_occured = false;
+}
+
+void SimpleAsm::setup(machine::MemoryAccess *mem, SymbolTableDb *symtab,
+                      std::uint32_t address) {
+    this->mem = mem;
+    this->symtab = symtab;
+    this->address = address;
+}
+
+bool SimpleAsm::process_line(QString line, QString filename,
+                             int line_number, QString *error_ptr) {
+    QString error;
+    int pos;
+    QString label = "";
+    pos = line.indexOf("#");
+    if (pos >= 0)
+        line.truncate(pos);
+    pos = line.indexOf(";");
+    if (pos >= 0)
+        line.truncate(pos);
+    pos = line.indexOf("//");
+    if (pos >= 0)
+        line.truncate(pos);
+    line = line.simplified();
+    pos = line.indexOf(":");
+    if (pos >= 0) {
+        label = line.mid(0, pos);
+        line = line.mid(pos + 1).trimmed();
+        symtab->setSymbol(label, address, 4);
+    }
+    if (line.isEmpty())
+        return true;
+    int k = 0, l;
+    while (k < line.count()) {
+        if (!line.at(k).isSpace())
+            break;
+        k++;
+    }
+    l = k;
+    while (l < line.count()) {
+        if (!line.at(l).isLetterOrNumber() && !(line.at(l) == '.'))
+            break;
+        l++;
+    }
+    QString op = line.mid(k, l - k).toUpper();
+    if ((op == ".DATA") || (op == ".TEXT") ||
+        (op == ".GLOBL") || (op == ".END") ||
+        (op == ".ENT")) {
+        return true;
+    }
+    if (op == ".ORG") {
+        bool ok;
+        fixmatheval::FmeExpression expression;
+        fixmatheval::FmeValue value;
+        ok = expression.parse(line.mid(op.size()), error);
+        if (ok)
+            ok = expression.eval(value, symtab, error);
+        if (!ok) {
+            error = tr("line %1 .orig %2 parse error.")
+                    .arg(QString::number(line_number), line);
+            emit report_message(messagetype::ERROR, filename, line_number, 0, error, "");
+            error_occured = true;
+            fatal_occured = true;
+            if (error_ptr != nullptr)
+                *error_ptr = error;
+            return false;
+        }
+        address = value;
+        return true;
+    }
+    if ((op == ".EQU") || (op == ".SET")) {
+        QStringList operands = line.mid(op.size()).split(",");
+        if ((operands.count() > 2) || (operands.count() < 1)) {
+            error = tr("line %1 .set or .equ incorrect arguments number.")
+                    .arg(QString::number(line_number));
+            emit report_message(messagetype::ERROR, filename, line_number, 0, error, "");
+            error_occured = true;
+            if (error_ptr != nullptr)
+                *error_ptr = error;
+            return false;
+        }
+        QString name = operands.at(0).trimmed();
+        if ((name == "noat") || (name == "noreored"))
+            return true;
+        bool ok;
+        fixmatheval::FmeValue value = 1;
+        if (operands.count() > 1) {
+            fixmatheval::FmeExpression expression;
+            ok = expression.parse(operands.at(1), error);
+            if (ok)
+                ok = expression.eval(value, symtab, error);
+            if (!ok) {
+                error = tr("line %1 .set or .equ %2 parse error.")
+                           .arg(QString::number(line_number), operands.at(1));
+                emit report_message(messagetype::ERROR, filename, line_number, 0, error, "");
+                error_occured = true;
+                if (error_ptr != nullptr)
+                    *error_ptr = error;
+                return false;
+            }
+        }
+        symtab->setSymbol(name, value, 0);
+        return true;
+    }
+    if (op == ".WORD") {
+        foreach (QString s, line.mid(op.size()).split(",")) {
+            s = s.simplified();
+            std::uint32_t val = 0;
+            int chars_taken;
+            val = string_to_uint64(s, 0, &chars_taken);
+            if (chars_taken != s.size()) {
+                val = 0;
+                reloc.append(new machine::RelocExpression(address, s, 0,
+                             -0xffffffff, 0xffffffff, 0, 32, 0, filename, line_number, 0));
+            }
+            if (fatal_occured)
+                mem->write_word(address, val);
+            address += 4;
+        }
+        return true;
+    }
+
+    std::uint32_t inst[2] = {0, 0};
+    ssize_t size = machine::Instruction::code_from_string(inst, 8, line, error,
+                                             address, &reloc, filename, line_number, true);
+    if (size < 0) {
+        error = tr("line %1 instruction %2 parse error - %3.")
+                .arg(QString::number(line_number), line, error);
+        emit report_message(messagetype::ERROR, filename, line_number, 0, error, "");
+        error_occured = true;
+        if (error_ptr != nullptr)
+            *error_ptr = error;
+        return false;
+    }
+    std::uint32_t *p = inst;
+    for (ssize_t l = 0; l < size; l += 4) {
+        if (!fatal_occured)
+            mem->write_word(address, *(p++));
+        address += 4;
+    }
+    return true;
+}
+
+bool SimpleAsm::finish(QString *error_ptr) {
+    bool error_reported = false;
+    foreach(machine::RelocExpression *r, reloc) {
+        QString error;
+        fixmatheval::FmeExpression expression;
+        if (!expression.parse(r->expression, error)) {
+            error = tr("expression parse error %1 at line %2, expression %3.")
+                    .arg(error, QString::number(r->line), expression.dump());
+            emit report_message(messagetype::ERROR, r->filename, r->line, 0, error, "");
+            if (error_ptr != nullptr && !error_reported)
+                *error_ptr = error;
+            error_occured = true;
+            error_reported = true;
+        } else {
+            fixmatheval::FmeValue value;
+            if (!expression.eval(value, symtab, error)) {
+                error = tr("expression evalution error %1 at line %2 , expression %3.")
+                        .arg(error, QString::number(r->line), expression.dump());
+                emit report_message(messagetype::ERROR, r->filename, r->line, 0, error, "");
+                if (error_ptr != nullptr && !error_reported)
+                    *error_ptr = error;
+                error_occured = true;
+                error_reported = true;
+            } else {
+                if (false)
+                    emit report_message(messagetype::INFO, r->filename, r->line, 0,
+                                   expression.dump() + " -> " + QString::number(value), "");
+                machine::Instruction inst(mem->read_word(r->location, true));
+                if (!inst.update(value, r)) {
+                    error = tr("instruction update error %1 at line %2, expression %3 -> value %4.")
+                            .arg(error, QString::number(r->line), expression.dump(), QString::number(value));
+                    emit report_message(messagetype::ERROR, r->filename, r->line, 0, error, "");
+                    if (error_ptr != nullptr && !error_reported)
+                        *error_ptr = error;
+                    error_occured = true;
+                    error_reported = true;
+                }
+                if (!fatal_occured)
+                    mem->write_word(r->location, inst.data());
+            }
+        }
+    }
+    while (!reloc.isEmpty()) {
+        delete reloc.takeFirst();
+    }
+
+    emit mem->external_change_notify(mem, 0, 0xffffffff, true);
+
+    return !error_occured;
+}
diff --git a/qtmips_asm/simpleasm.h b/qtmips_asm/simpleasm.h
new file mode 100644
index 0000000..773aa39
--- /dev/null
+++ b/qtmips_asm/simpleasm.h
@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*******************************************************************************
+ * QtMips - MIPS 32-bit Architecture Subset Simulator
+ *
+ * Implemented to support following courses:
+ *
+ *   B35APO - Computer Architectures
+ *   https://cw.fel.cvut.cz/wiki/courses/b35apo
+ *
+ *   B4M35PAP - Advanced Computer Architectures
+ *   https://cw.fel.cvut.cz/wiki/courses/b4m35pap/start
+ *
+ * Copyright (c) 2017-2019 Karel Koci<cynerd@email.cz>
+ * Copyright (c) 2019      Pavel Pisa <pisa@cmp.felk.cvut.cz>
+ *
+ * Faculty of Electrical Engineering (http://www.fel.cvut.cz)
+ * Czech Technical University        (http://www.cvut.cz/)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA  02110-1301, USA.
+ *
+ ******************************************************************************/
+
+#ifndef  SIMPLEASM_H
+#define  SIMPLEASM_H
+
+#include  <QString>
+#include "fixmatheval.h"
+#include "qtmipsmachine.h"
+#include "messagetype.h"
+
+class SymbolTableDb : public fixmatheval::FmeSymbolDb {
+public:
+    SymbolTableDb(machine::SymbolTable *symtab);
+    virtual bool getValue(fixmatheval::FmeValue &value, QString name) override;
+    void setSymbol(QString name, std::uint32_t value, std::uint32_t size,
+              unsigned char info = 0, unsigned char other = 0);
+private:
+    machine::SymbolTable *symtab;
+};
+
+class SimpleAsm : public QObject {
+    Q_OBJECT
+
+    using Super = QObject;
+
+signals:
+    void report_message(messagetype::Type type, QString file, int line,
+                                   int column, QString text, QString hint);
+
+public:
+    SimpleAsm(QObject *parent = nullptr);
+    ~SimpleAsm();
+public:
+    static std::uint64_t string_to_uint64(QString str, int base,
+                                          int *chars_taken = nullptr);
+    void clear();
+    void setup(machine::MemoryAccess *mem, SymbolTableDb *symtab, std::uint32_t address);
+    bool process_line(QString line, QString filename = "",
+                      int line_number = 0, QString *error_ptr = nullptr);
+    bool finish(QString *error_ptr = nullptr);
+private:
+    bool error_occured;
+    bool fatal_occured;
+    SymbolTableDb *symtab;
+    machine::MemoryAccess *mem;
+    machine::RelocExpressionList reloc;
+    std::uint32_t address;
+};
+
+#endif /*SIMPLEASM_H*/
diff --git a/qtmips_gui/mainwindow.cpp b/qtmips_gui/mainwindow.cpp
index 0498ff3..87549d2 100644
--- a/qtmips_gui/mainwindow.cpp
+++ b/qtmips_gui/mainwindow.cpp
@@ -50,6 +50,7 @@
 #include "fontsize.h"
 #include "gotosymboldialog.h"
 #include "fixmatheval.h"
+#include "simpleasm.h"
 
 #ifdef __EMSCRIPTEN__
 #include <QFileInfo>
@@ -691,45 +692,9 @@ void MainWindow::message_selected(messagetype::Type type, QString file, int line
         central_window->setCurrentWidget(editor);
 }
 
-class SymbolTableDb : public fixmatheval::FmeSymbolDb {
-public:
-    SymbolTableDb(const machine::SymbolTable *symtab);
-    virtual bool getValue(fixmatheval::FmeValue &value, QString name) override;
-private:
-    const machine::SymbolTable *symtab;
-};
-
-SymbolTableDb::SymbolTableDb(const machine::SymbolTable *symtab) {
-    this->symtab = symtab;
-}
-
-bool SymbolTableDb::getValue(fixmatheval::FmeValue &value, QString name) {
-    std::uint32_t val;
-    if (!symtab->name_to_value(val, name))
-        return false;
-    value = val;
-    return true;
-}
-
-static std::uint64_t string_to_uint64(QString str, int base,
-                                      int *chars_taken = nullptr) {
-    int i;
-    std::int64_t val;
-    char *p, *r;
-    char cstr[str.count() + 1];
-    for (i = 0; i < str.count(); i++)
-        cstr[i] = str.at(i).toLatin1();
-    cstr[i] = 0;
-    p = cstr;
-    val = std::strtoll(p, &r, base);
-    if (chars_taken != nullptr)
-        *chars_taken = r - p;
-    return val;
-}
-
 void MainWindow::compile_source() {
-    SymbolTableDb symtab(machine->symbol_table(true));
-    int error_line = 0;
+    SymbolTableDb symtab(machine->symbol_table_rw(true));
+    bool error_occured;
     if (current_srceditor == nullptr)
         return;
     if (machine == nullptr) {
@@ -745,169 +710,24 @@ void MainWindow::compile_source() {
     machine->cache_sync();
     SrcEditor *editor = current_srceditor;
     QTextDocument *doc = editor->document();
-    std::uint32_t address = 0x80020000;
-    machine::RelocExpressionList reloc;
 
     emit clear_messages();
+    SimpleAsm sasm;
+
+    connect(&sasm, SIGNAL(report_message(messagetype::Type,QString,int,int,QString,QString)),
+            this, SIGNAL(report_message(messagetype::Type,QString,int,int,QString,QString)));
+
+    sasm.setup(mem, &symtab, 0x80020000);
 
     int ln = 1;
     for ( QTextBlock block = doc->begin(); block.isValid(); block = block.next(), ln++) {
-        QString error;
-        int pos;
-        QString label = "";
         QString line = block.text();
-        pos = line.indexOf("#");
-        if (pos >= 0)
-            line.truncate(pos);
-        pos = line.indexOf(";");
-        if (pos >= 0)
-            line.truncate(pos);
-        pos = line.indexOf("//");
-        if (pos >= 0)
-            line.truncate(pos);
-        line = line.simplified();
-        pos = line.indexOf(":");
-        if (pos >= 0) {
-            label = line.mid(0, pos);
-            line = line.mid(pos + 1).trimmed();
-            machine->set_symbol(label, address, 4);
-        }
-        if (line.isEmpty())
-            continue;
-        int k = 0, l;
-        while (k < line.count()) {
-            if (!line.at(k).isSpace())
-                break;
-            k++;
-        }
-        l = k;
-        while (l < line.count()) {
-            if (!line.at(l).isLetterOrNumber() && !(line.at(l) == '.'))
-                break;
-            l++;
-        }
-        QString op = line.mid(k, l - k).toUpper();
-        if ((op == ".DATA") || (op == ".TEXT") ||
-            (op == ".GLOBL") || (op == ".END") ||
-            (op == ".ENT")) {
-            continue;
-        }
-        if (op == ".ORG") {
-            bool ok;
-            fixmatheval::FmeExpression expression;
-            fixmatheval::FmeValue value;
-            ok = expression.parse(line.mid(op.size()), error);
-            if (ok)
-                ok = expression.eval(value, &symtab, error);
-            if (!ok) {
-                error_line = ln;
-                emit report_message(messagetype::ERROR, filename, ln, 0,
-                               tr("line %1 .orig %2 parse error.")
-                               .arg(QString::number(ln), line), "");
-                break;
-            }
-            address = value;
-            continue;
-        }
-        if ((op == ".EQU") || (op == ".SET")) {
-            QStringList operands = line.mid(op.size()).split(",");
-            if ((operands.count() > 2) || (operands.count() < 1)) {
-                error_line = ln;
-                emit report_message(messagetype::ERROR, filename, ln, 0,
-                               tr("line %1 .set or .equ incorrect arguments number.")
-                               .arg(QString::number(ln)), "");
-                continue;
-            }
-            QString name = operands.at(0).trimmed();
-            if ((name == "noat") || (name == "noreored"))
-                continue;
-            bool ok;
-            fixmatheval::FmeValue value = 1;
-            if (operands.count() > 1) {
-                fixmatheval::FmeExpression expression;
-                ok = expression.parse(operands.at(1), error);
-                if (ok)
-                    ok = expression.eval(value, &symtab, error);
-                if (!ok) {
-                    error_line = ln;
-                    emit report_message(messagetype::ERROR, filename, ln, 0,
-                                  tr("line %1 .set or .equ %2 parse error.")
-                                  .arg(QString::number(ln), operands.at(1)), "");
-                    continue;
-                }
-            }
-            machine->set_symbol(name, value, 0);
-            continue;
-        }
-        if (op == ".WORD") {
-            foreach (QString s, line.mid(op.size()).split(",")) {
-                s = s.simplified();
-                std::uint32_t val = 0;
-                int chars_taken;
-                val = string_to_uint64(s, 0, &chars_taken);
-                if (chars_taken != s.size()) {
-                    val = 0;
-                    reloc.append(new machine::RelocExpression(address, s, 0,
-                                 -0xffffffff, 0xffffffff, 0, 32, 0, ln, 0));
-                }
-                mem->write_word(address, val);
-                address += 4;
-            }
-            continue;
-        }
-
-        std::uint32_t inst[2] = {0, 0};
-        ssize_t size = machine::Instruction::code_from_string(inst, 8, line, error,
-                                                 address, &reloc, ln, true);
-        if (size < 0) {
-            error_line = ln;
-            emit report_message(messagetype::ERROR, filename, ln, 0,
-                              tr("line %1 instruction %2 parse error - %3.")
-                              .arg(QString::number(ln), line, error), "");
-            continue;
-        }
-        std::uint32_t *p = inst;
-        for (ssize_t l = 0; l < size; l += 4) {
-            mem->write_word(address, *(p++));
-            address += 4;
-        }
+        if (!sasm.process_line(line, filename, ln))
+            error_occured = true;
     }
-    foreach(machine::RelocExpression *r, reloc) {
-        QString error;
-        fixmatheval::FmeExpression expression;
-        if (!expression.parse(r->expression, error)) {
-            error_line = r->line;
-            emit report_message(messagetype::ERROR, filename, ln, 0,
-                                tr("expression parse error %1 at line %2, expression %3.")
-                                .arg(error, QString::number(r->line), expression.dump()), "");
-        } else {
-            fixmatheval::FmeValue value;
-            if (!expression.eval(value, &symtab, error)) {
-                error_line = r->line;
-                emit report_message(messagetype::ERROR, filename, ln, 0,
-                               tr("expression evalution error %1 at line %2 , expression %3.")
-                               .arg(error, QString::number(r->line), expression.dump()), "");
-            } else {
-                if (false)
-                    emit report_message(messagetype::INFO, filename, ln, 0,
-                                   expression.dump() + " -> " + QString::number(value), "");
-                machine::Instruction inst(mem->read_word(r->location, true));
-                if (!inst.update(value, r)) {
-                    error_line = r->line;
-                    emit report_message(messagetype::ERROR, filename, ln, 0,
-                                   tr("instruction update error %1 at line %2, expression %3 -> value %4.")
-                                   .arg(error, QString::number(r->line), expression.dump(), QString::number(value)), "");
-                }
-                mem->write_word(r->location, inst.data());
-            }
-        }
-    }
-    while (!reloc.isEmpty()) {
-        delete reloc.takeFirst();
-    }
-
-    emit mem->external_change_notify(mem, 0, 0xffffffff, true);
+    if (!sasm.finish())
+        error_occured = true;
 
-    if (error_line != 0)
+    if (error_occured)
         show_messages();
 }
diff --git a/qtmips_machine/instruction.cpp b/qtmips_machine/instruction.cpp
index b30901f..547c666 100644
--- a/qtmips_machine/instruction.cpp
+++ b/qtmips_machine/instruction.cpp
@@ -1111,7 +1111,7 @@ static int parse_reg_from_string(QString str, uint *chars_taken = nullptr)
 
 static void reloc_append(RelocExpressionList *reloc, QString fl, uint32_t inst_addr,
                     std::int64_t offset, const ArgumentDesc *adesc, uint *chars_taken = nullptr,
-                    int line = 0, int options = 0) {
+                    QString filename = "", int line = 0, int options = 0) {
     uint bits = IMF_SUB_GET_BITS(adesc->loc);
     uint shift = IMF_SUB_GET_SHIFT(adesc->loc);
     QString expression = "";
@@ -1130,7 +1130,7 @@ static void reloc_append(RelocExpressionList *reloc, QString fl, uint32_t inst_a
     }
 
     reloc->append(new RelocExpression(inst_addr, expression, offset,
-                  adesc->min, adesc->max, shift, bits, adesc->shift, line, options));
+                  adesc->min, adesc->max, shift, bits, adesc->shift, filename, line, options));
     if (chars_taken != nullptr) {
         *chars_taken = i;
     }
@@ -1141,7 +1141,7 @@ static void reloc_append(RelocExpressionList *reloc, QString fl, uint32_t inst_a
 ssize_t Instruction::code_from_string(std::uint32_t *code, size_t buffsize,
                        QString inst_base, QStringList &inst_fields, QString &error,
                        std::uint32_t inst_addr, RelocExpressionList *reloc,
-                       int line, bool pseudo_opt, int options)
+                       QString filename, int line, bool pseudo_opt, int options)
 {
     const char *err = "unknown instruction";
     if (str_to_instruction_code_map.isEmpty())
@@ -1236,7 +1236,7 @@ ssize_t Instruction::code_from_string(std::uint32_t *code, size_t buffsize,
                         need_reloc = true;
                     }
                     if (need_reloc && (reloc != nullptr)) {
-                        reloc_append(reloc, fl, inst_addr, val, adesc, &chars_taken, line, options);
+                        reloc_append(reloc, fl, inst_addr, val, adesc, &chars_taken, filename, line, options);
                         val = 0;
                     }
                     break;
@@ -1263,7 +1263,7 @@ ssize_t Instruction::code_from_string(std::uint32_t *code, size_t buffsize,
                         need_reloc = true;
                     }
                     if (need_reloc && (reloc != nullptr)) {
-                        reloc_append(reloc, fl, inst_addr, val, adesc, &chars_taken, line, options);
+                        reloc_append(reloc, fl, inst_addr, val, adesc, &chars_taken, filename, line, options);
                         val = 0;
                     }
                     break;
@@ -1328,14 +1328,14 @@ ssize_t Instruction::code_from_string(std::uint32_t *code, size_t buffsize,
     } else if (pseudo_opt) {
         if (((inst_base == "LA") || (inst_base == "LI")) && (inst_fields.size() == 2)) {
             if(code_from_string(code, buffsize, "LUI", inst_fields, error,
-                             inst_addr, reloc, line, false,
+                             inst_addr, reloc, filename, line, false,
                              CFS_OPTION_SILENT_MASK + 16) < 0) {
                 error = QString("error in LUI element of " + inst_base);
                 return -1;
             }
             inst_fields.insert(1, inst_fields.at(0));
             if (code_from_string(code + 1, buffsize - 4, "ORI", inst_fields, error,
-                             inst_addr + 4, reloc, line, false,
+                             inst_addr + 4, reloc, filename, line, false,
                              CFS_OPTION_SILENT_MASK + 0) < 0) {
                 error = QString("error in ORI element of " + inst_base);
                 return -1;
@@ -1353,7 +1353,8 @@ ssize_t Instruction::code_from_string(std::uint32_t *code, size_t buffsize,
 
 ssize_t Instruction::code_from_string(std::uint32_t *code, size_t buffsize,
                        QString str, QString &error, std::uint32_t inst_addr,
-                       RelocExpressionList *reloc, int line, bool pseudo_opt, int options)
+                       RelocExpressionList *reloc, QString filename, int line,
+                       bool pseudo_opt, int options)
 {
     int k = 0, l;
     while (k < str.count()) {
@@ -1379,7 +1380,7 @@ ssize_t Instruction::code_from_string(std::uint32_t *code, size_t buffsize,
     }
 
     return code_from_string(code, buffsize, inst_base, inst_fields, error, inst_addr,
-                            reloc, line, pseudo_opt, options);
+                            reloc, filename, line, pseudo_opt, options);
 }
 
 bool Instruction::update(std::int64_t val, RelocExpression *relocexp) {
diff --git a/qtmips_machine/instruction.h b/qtmips_machine/instruction.h
index b07a0e8..2ecd0c4 100644
--- a/qtmips_machine/instruction.h
+++ b/qtmips_machine/instruction.h
@@ -78,8 +78,8 @@ enum InstructionFlags {
 
 struct RelocExpression {
     inline RelocExpression(std::int32_t location, QString expression, std::int64_t offset, std::int64_t min,
-                           std::int64_t max, unsigned lsb_bit, unsigned bits, unsigned shift, int line,
-                           int options) {
+                           std::int64_t max, unsigned lsb_bit, unsigned bits, unsigned shift,
+                           QString filename, int line, int options) {
         this->location = location;
         this->expression = expression;
         this->offset = offset;
@@ -88,6 +88,7 @@ struct RelocExpression {
         this->lsb_bit = lsb_bit;
         this->bits = bits;
         this->shift = shift;
+        this->filename = filename;
         this->line = line;
         this->options = options;
     }
@@ -99,6 +100,7 @@ struct RelocExpression {
     unsigned      lsb_bit;
     unsigned      bits;
     unsigned      shift;
+    QString       filename;
     int           line;
     int           options;
 };
@@ -152,11 +154,11 @@ public:
                            QString inst_base, QStringList &inst_fields, QString &error,
                            std::uint32_t inst_addr = 0,
                            RelocExpressionList *reloc = nullptr,
-                           int line = 0, bool pseudo_opt = false, int options = 0);
+                           QString filename = "", int line = 0, bool pseudo_opt = false, int options = 0);
 
     static ssize_t code_from_string(std::uint32_t *code, size_t buffsize,
                            QString str, QString &error, std::uint32_t inst_addr = 0,
-                           RelocExpressionList *reloc = nullptr,
+                           RelocExpressionList *reloc = nullptr, QString filename = "",
                            int line = 0, bool pseudo_opt = false, int options = 0);
 
     bool update(std::int64_t val, RelocExpression *relocexp);
diff --git a/qtmips_machine/qtmipsmachine.cpp b/qtmips_machine/qtmipsmachine.cpp
index e838429..b726bba 100644
--- a/qtmips_machine/qtmipsmachine.cpp
+++ b/qtmips_machine/qtmipsmachine.cpp
@@ -193,7 +193,6 @@ void QtMipsMachine::cache_sync() {
         cch_data->sync();
 }
 
-
 const PhysAddrSpace *QtMipsMachine::physical_address_space() {
     return physaddrspace;
 }
@@ -214,19 +213,22 @@ LcdDisplay *QtMipsMachine::peripheral_lcd_display() {
     return perip_lcd_display;
 }
 
-const SymbolTable *QtMipsMachine::symbol_table(bool create) {
+SymbolTable *QtMipsMachine::symbol_table_rw(bool create) {
     if (create && (symtab == nullptr))
         symtab = new SymbolTable;
     return symtab;
 }
 
+const SymbolTable *QtMipsMachine::symbol_table(bool create) {
+    return symbol_table_rw(create);
+}
+
 void QtMipsMachine::set_symbol(QString name, std::uint32_t value,
                                std::uint32_t size, unsigned char info,
                                unsigned char other) {
     if (symtab == nullptr)
         symtab = new SymbolTable;
-    symtab->remove_symbol(name);
-    symtab->add_symbol(name, value, size, info, other);
+    symtab->set_symbol(name, value, size, info, other);
 }
 
 const Core *QtMipsMachine::core() {
diff --git a/qtmips_machine/qtmipsmachine.h b/qtmips_machine/qtmipsmachine.h
index e5bbdb3..7092ec3 100644
--- a/qtmips_machine/qtmipsmachine.h
+++ b/qtmips_machine/qtmipsmachine.h
@@ -77,6 +77,7 @@ public:
     PeripSpiLed *peripheral_spi_led();
     LcdDisplay *peripheral_lcd_display();
     const SymbolTable *symbol_table(bool create = false);
+    SymbolTable *symbol_table_rw(bool create = false);
     void set_symbol(QString name, std::uint32_t value, std::uint32_t size,
                     unsigned char info = 0, unsigned char other = 0);
     const Core *core();
diff --git a/qtmips_machine/symboltable.cpp b/qtmips_machine/symboltable.cpp
index d26491f..987b35f 100644
--- a/qtmips_machine/symboltable.cpp
+++ b/qtmips_machine/symboltable.cpp
@@ -75,6 +75,12 @@ void SymbolTable::remove_symbol(QString name) {
     delete p_ste;
 }
 
+void SymbolTable::set_symbol(QString name, std::uint32_t value, std::uint32_t size,
+          unsigned char info, unsigned char other) {
+    remove_symbol(name);
+    add_symbol(name, value, size, info, other);
+}
+
 bool SymbolTable::name_to_value(std::uint32_t &value, QString name) const {
     SymbolTableEntry *p_ste = map_name_to_symbol.value(name);
     if (p_ste == nullptr) {
diff --git a/qtmips_machine/symboltable.h b/qtmips_machine/symboltable.h
index 0c33ac3..ece92a9 100644
--- a/qtmips_machine/symboltable.h
+++ b/qtmips_machine/symboltable.h
@@ -65,6 +65,8 @@ public:
 
     void add_symbol(QString name, std::uint32_t value, std::uint32_t size,
               unsigned char info = 0, unsigned char other = 0);
+    void set_symbol(QString name, std::uint32_t value, std::uint32_t size,
+              unsigned char info = 0, unsigned char other = 0);
     void remove_symbol(QString name);
     QStringList *names() const;
 public slots: