Add basic Structured Text parser

Includes support for simple arithmetic and boolean expressions as well
as other ST language features, such as networks, functions and function
blocks.

Author: MatWise

.gitignore

@@ -84,6 +84,10 @@ src/json/json_lex.yy.cpp
 src/json/json_y.output
 src/json/json_y.tab.cpp
 src/json/json_y.tab.h
+src/structured-text/structured_text_lex.yy.cpp
+src/structured-text/structured_text_y.output
+src/structured-text/structured_text_y.tab.cpp
+src/structured-text/structured_text_y.tab.h
 src/xmllang/xml_lex.yy.cpp
 src/xmllang/xml_y.output
 src/xmllang/xml_y.tab.cpp

src/structured-text/converters/convert_bool_literal.cpp

@@ -0,0 +1,26 @@
+/*******************************************************************\
+
+Module: Structured Text Language Conversion
+
+Author: Matthias Weiss, [email protected]
+
+\*******************************************************************/
+
+/// \file
+/// Structured Text Language Conversion
+
+#include "convert_bool_literal.h"
+#include <algorithm>
+#include <util/std_types.h>
+
+constant_exprt convert_bool_literal(const std::string &src)
+{
+  // Transform to lower case.
+  std::string copy;
+  std::transform(src.begin(), src.end(), copy.begin(), ::tolower);
+
+  bool_typet type;
+  type.set(ID_structured_text_type, ID_structured_text_bool);
+
+  return constant_exprt(copy, type);
+}

src/structured-text/converters/convert_bool_literal.h

@@ -0,0 +1,25 @@
+/*******************************************************************\
+
+Module: Structured Text Language Conversion
+
+Author: Matthias Weiss, [email protected]
+
+\*******************************************************************/
+
+/// \file
+/// Structured Text Language Conversion
+
+#ifndef CPROVER_STRUCTURED_TEXT_CONVERTERS_CONVERT_BOOL_LITERAL_H
+#define CPROVER_STRUCTURED_TEXT_CONVERTERS_CONVERT_BOOL_LITERAL_H
+
+#include <string>
+
+#include <util/expr.h>
+#include <util/std_expr.h>
+
+/// Converts a string into the corresponding 'Bool' expression.
+/// \param src: String returned by the parser.
+/// \return Constant expression representing the boolean value.
+constant_exprt convert_bool_literal(const std::string &src);
+
+#endif // CPROVER_STRUCTURED_TEXT_CONVERTERS_CONVERT_INT_LITERAL_H

src/structured-text/converters/convert_int_literal.cpp

@@ -0,0 +1,50 @@
+/*******************************************************************\
+
+Module: Structured Text Language Conversion
+
+Author: Matthias Weiss, [email protected]
+
+\*******************************************************************/
+
+/// \file
+/// Structured Text Language Conversion
+
+#include "convert_int_literal.h"
+#include <algorithm>
+#include <util/std_types.h>
+
+constant_exprt convert_int_dec_literal(const std::string &src)
+{
+  // Remove '+' char if present.
+  std::string value(src);
+  value.erase(std::remove(value.begin(), value.end(), '+'), value.end());
+
+  signedbv_typet type{16};
+  type.set(ID_structured_text_type, ID_structured_text_int);
+
+  return constant_exprt(value, type);
+}
+
+constant_exprt convert_int_hex_literal(const std::string &src)
+{
+  // Cut the leading '16#' and convert to int
+  std::string cut = src.substr(3, std::string::npos);
+  int value = std::stoi(cut, nullptr, 16);
+
+  signedbv_typet type{16};
+  type.set(ID_structured_text_type, ID_structured_text_int);
+
+  return constant_exprt(std::to_string(value), type);
+}
+
+constant_exprt convert_int_bit_literal(const std::string &src)
+{
+  // Cut the leading '2#' and convert to int
+  std::string cut = src.substr(2, std::string::npos);
+  int value = std::stoi(cut, nullptr, 2);
+
+  signedbv_typet type{16};
+  type.set(ID_structured_text_type, ID_structured_text_int);
+
+  return constant_exprt(std::to_string(value), type);
+}

src/structured-text/converters/convert_int_literal.h

@@ -0,0 +1,35 @@
+/*******************************************************************\
+
+Module: Structured Text Language Conversion
+
+Author: Matthias Weiss, [email protected]
+
+\*******************************************************************/
+
+/// \file
+/// Structured Text Language Conversion
+
+#ifndef CPROVER_STRUCTURED_TEXT_CONVERTERS_CONVERT_INT_LITERAL_H
+#define CPROVER_STRUCTURED_TEXT_CONVERTERS_CONVERT_INT_LITERAL_H
+
+#include <string>
+
+#include <util/expr.h>
+#include <util/std_expr.h>
+
+/// Converts a string into the corresponding 'Int' expression.
+/// \param src: String returned by the parser (base 10).
+/// \return Constant expression representing the integer value.
+constant_exprt convert_int_dec_literal(const std::string &src);
+
+/// Converts a string into the corresponding 'Int' expression.
+/// \param src: String returned by the parser (base 16).
+/// \return Constant expression representing the integer value.
+constant_exprt convert_int_hex_literal(const std::string &src);
+
+/// Converts a string into the corresponding 'Int' expression.
+/// \param src: String returned by the parser (base 2).
+/// \return Constant expression representing the integer value.
+constant_exprt convert_int_bit_literal(const std::string &src);
+
+#endif // CPROVER_STRUCTURED_TEXT_CONVERTERS_CONVERT_INT_LITERAL_H

src/structured-text/converters/convert_real_literal.cpp

@@ -0,0 +1,22 @@
+/*******************************************************************\
+
+Module: Structured Text Language Conversion
+
+Author: Matthias Weiss, [email protected]
+
+\*******************************************************************/
+
+/// \file
+/// Structured Text Language Conversion
+
+#include "convert_real_literal.h"
+#include <util/ieee_float.h>
+#include <util/std_expr.h>
+
+constant_exprt convert_real_literal(const std::string &src)
+{
+  floatbv_typet type = ieee_float_spect::single_precision().to_type();
+  type.set(ID_structured_text_type, ID_structured_text_real);
+
+  return constant_exprt(src, type);
+}

src/structured-text/converters/convert_real_literal.h

@@ -0,0 +1,25 @@
+/*******************************************************************\
+
+Module: Structured Text Language Conversion
+
+Author: Matthias Weiss, [email protected]
+
+\*******************************************************************/
+
+/// \file
+/// Structured Text Language Conversion
+
+#ifndef CPROVER_STRUCTURED_TEXT_CONVERTERS_CONVERT_REAL_LITERAL_H
+#define CPROVER_STRUCTURED_TEXT_CONVERTERS_CONVERT_REAL_LITERAL_H
+
+#include <string>
+
+#include <util/expr.h>
+#include <util/std_types.h>
+
+/// Converts a string into the corresponding 'Real' expression.
+/// \param src: String returned by the parser.
+/// \return Constant expression representing the real value.
+constant_exprt convert_real_literal(const std::string &src);
+
+#endif // CPROVER_STRUCTURED_TEXT_CONVERTERS_CONVERT_REAL_VALUE_H

src/structured-text/converters/convert_string_value.cpp

@@ -0,0 +1,34 @@
+/*******************************************************************\
+
+Module: Structured Text Language Conversion
+
+Author: Matthias Weiss, [email protected]
+
+\*******************************************************************/
+
+/// \file
+/// Structured Text Language Conversion
+
+#include "convert_string_value.h"
+
+string_constantt convert_identifier(const std::string &src)
+{
+  string_constantt result{src};
+  result.set(ID_structured_text_type, ID_structured_text_identifier);
+  return result;
+}
+
+string_constantt convert_title(const std::string &src)
+{
+  string_constantt result{src};
+  result.set(ID_structured_text_type, ID_structured_text_title);
+  return result;
+}
+
+code_labelt convert_label(const std::string &src)
+{
+  // Cut the trailing colon
+  std::string value = src.substr(0, src.length() - 1);
+
+  return code_labelt{value, codet(ID_label)};
+}

src/structured-text/converters/convert_string_value.h

@@ -0,0 +1,34 @@
+/*******************************************************************\
+
+Module: Structured Text Language Conversion
+
+Author: Matthias Weiss, [email protected]
+
+\*******************************************************************/
+
+/// \file
+/// Structured Text Language Conversion
+
+#ifndef CPROVER_STRUCTURED_TEXT_CONVERTERS_CONVERT_STRING_VALUE_H
+#define CPROVER_STRUCTURED_TEXT_CONVERTERS_CONVERT_STRING_VALUE_H
+
+#include <util/expr.h>
+#include <util/std_code.h>
+#include <util/string_constant.h>
+
+/// Converts a string into a Structured Text identifier.
+/// \param src: String returned by the parser.
+/// \return Constant string expression representing the identifier.
+string_constantt convert_identifier(const std::string &src);
+
+/// Converts a string into a Structured Text title.
+/// \param src: String returned by the parser.
+/// \return Constant string expression representing the title.
+string_constantt convert_title(const std::string &src);
+
+/// Converts a string into a Structured Text label.
+/// \param src: String returned by the parser.
+/// \return Code label expression representing the label.
+code_labelt convert_label(const std::string &src);
+
+#endif // CPROVER_STRUCTURED_TEXT_CONVERTERS_CONVERT_STRING_VALUE_H

src/structured-text/converters/module_dependencies.txt

@@ -0,0 +1,3 @@
+structured-text
+structured-text/converters
+util

src/structured-text/module_dependencies.txt

@@ -0,0 +1,5 @@
+converters
+langapi
+linking
+structured-text
+util