// license:BSD-3-Clause // copyright-holders:Aaron Giles /*************************************************************************** express.c Generic expressions engine. **************************************************************************** Operator precedence =================== 0x0000 ( ) 0x0001 ++ (postfix), -- (postfix) 0x0002 ++ (prefix), -- (prefix), ~, !, - (unary), + (unary), b@, w@, d@, q@ 0x0003 *, /, % 0x0004 + - 0x0005 << >> 0x0006 < <= > >= 0x0007 == != 0x0008 & 0x0009 ^ 0x000a | 0x000b && 0x000c || 0x000d = *= /= %= += -= <<= >>= &= |= ^= 0x000e , 0x000f func() ***************************************************************************/ #include "emu.h" #include "express.h" #include /*************************************************************************** DEBUGGING ***************************************************************************/ #define DEBUG_TOKENS 0 /*************************************************************************** CONSTANTS ***************************************************************************/ #ifndef DEFAULT_BASE #define DEFAULT_BASE 16 // hex unless otherwise specified #endif // token.value values if token.is_operator() enum { TVL_LPAREN, TVL_RPAREN, TVL_PLUSPLUS, TVL_MINUSMINUS, TVL_PREINCREMENT, TVL_PREDECREMENT, TVL_POSTINCREMENT, TVL_POSTDECREMENT, TVL_COMPLEMENT, TVL_NOT, TVL_UPLUS, TVL_UMINUS, TVL_MULTIPLY, TVL_DIVIDE, TVL_MODULO, TVL_ADD, TVL_SUBTRACT, TVL_LSHIFT, TVL_RSHIFT, TVL_LESS, TVL_LESSOREQUAL, TVL_GREATER, TVL_GREATEROREQUAL, TVL_EQUAL, TVL_NOTEQUAL, TVL_BAND, TVL_BXOR, TVL_BOR, TVL_LAND, TVL_LOR, TVL_ASSIGN, TVL_ASSIGNMULTIPLY, TVL_ASSIGNDIVIDE, TVL_ASSIGNMODULO, TVL_ASSIGNADD, TVL_ASSIGNSUBTRACT, TVL_ASSIGNLSHIFT, TVL_ASSIGNRSHIFT, TVL_ASSIGNBAND, TVL_ASSIGNBXOR, TVL_ASSIGNBOR, TVL_COMMA, TVL_MEMORYAT, TVL_EXECUTEFUNC }; //************************************************************************** // TYPE DEFINITIONS //************************************************************************** // a symbol entry representing a register, with read/write callbacks class integer_symbol_entry : public symbol_entry { public: // construction/destruction integer_symbol_entry(symbol_table &table, const char *name, symbol_table::read_write rw, UINT64 *ptr = NULL); integer_symbol_entry(symbol_table &table, const char *name, UINT64 constval); integer_symbol_entry(symbol_table &table, const char *name, void *ref, symbol_table::getter_func getter, symbol_table::setter_func setter); // symbol access virtual bool is_lval() const; virtual UINT64 value() const; virtual void set_value(UINT64 newvalue); private: // internal helpers static UINT64 internal_getter(symbol_table &table, void *symref); static void internal_setter(symbol_table &table, void *symref, UINT64 value); // internal state symbol_table::getter_func m_getter; symbol_table::setter_func m_setter; UINT64 m_value; }; // a symbol entry representing a function class function_symbol_entry : public symbol_entry { public: // construction/destruction function_symbol_entry(symbol_table &table, const char *name, void *ref, int minparams, int maxparams, symbol_table::execute_func execute); // symbol access virtual bool is_lval() const; virtual UINT64 value() const; virtual void set_value(UINT64 newvalue); // execution helper virtual UINT64 execute(int numparams, const UINT64 *paramlist); private: // internal state UINT16 m_minparams; UINT16 m_maxparams; symbol_table::execute_func m_execute; }; //************************************************************************** // EXPRESSION ERROR //************************************************************************** //------------------------------------------------- // code_string - return a friendly string for a // given expression error //------------------------------------------------- const char *expression_error::code_string() const { switch (m_code) { case NOT_LVAL: return "not an lvalue"; case NOT_RVAL: return "not an rvalue"; case SYNTAX: return "syntax error"; case UNKNOWN_SYMBOL: return "unknown symbol"; case INVALID_NUMBER: return "invalid number"; case INVALID_TOKEN: return "invalid token"; case STACK_OVERFLOW: return "stack overflow"; case STACK_UNDERFLOW: return "stack underflow"; case UNBALANCED_PARENS: return "unbalanced parentheses"; case DIVIDE_BY_ZERO: return "divide by zero"; case OUT_OF_MEMORY: return "out of memory"; case INVALID_PARAM_COUNT: return "invalid number of parameters"; case UNBALANCED_QUOTES: return "unbalanced quotes"; case TOO_MANY_STRINGS: return "too many strings"; case INVALID_MEMORY_SIZE: return "invalid memory size (b/w/d/q expected)"; case NO_SUCH_MEMORY_SPACE: return "non-existent memory space"; case INVALID_MEMORY_SPACE: return "invalid memory space (p/d/i/o/r/m expected)"; case INVALID_MEMORY_NAME: return "invalid memory name"; case MISSING_MEMORY_NAME: return "missing memory name"; default: return "unknown error"; } } //************************************************************************** // SYMBOL ENTRY //************************************************************************** //------------------------------------------------- // symbol_entry - constructor //------------------------------------------------- symbol_entry::symbol_entry(symbol_table &table, symbol_type type, const char *name, void *ref) : m_next(NULL), m_table(table), m_type(type), m_name(name), m_ref(ref) { } //------------------------------------------------- // ~symbol_entry - destructor //------------------------------------------------- symbol_entry::~symbol_entry() { } //************************************************************************** // REGISTER SYMBOL ENTRY //************************************************************************** //------------------------------------------------- // integer_symbol_entry - constructor //------------------------------------------------- integer_symbol_entry::integer_symbol_entry(symbol_table &table, const char *name, symbol_table::read_write rw, UINT64 *ptr) : symbol_entry(table, SMT_INTEGER, name, (ptr == NULL) ? &m_value : ptr), m_getter(internal_getter), m_setter((rw == symbol_table::READ_ONLY) ? NULL : internal_setter), m_value(0) { } integer_symbol_entry::integer_symbol_entry(symbol_table &table, const char *name, UINT64 constval) : symbol_entry(table, SMT_INTEGER, name, &m_value), m_getter(internal_getter), m_setter(NULL), m_value(constval) { } integer_symbol_entry::integer_symbol_entry(symbol_table &table, const char *name, void *ref, symbol_table::getter_func getter, symbol_table::setter_func setter) : symbol_entry(table, SMT_INTEGER, name, ref), m_getter(getter), m_setter(setter), m_value(0) { } //------------------------------------------------- // is_lval - is this symbol allowable as an lval? //------------------------------------------------- bool integer_symbol_entry::is_lval() const { return (m_setter != NULL); } //------------------------------------------------- // value - return the value of this symbol //------------------------------------------------- UINT64 integer_symbol_entry::value() const { return (*m_getter)(m_table, m_ref); } //------------------------------------------------- // set_value - set the value of this symbol //------------------------------------------------- void integer_symbol_entry::set_value(UINT64 newvalue) { if (m_setter != NULL) (*m_setter)(m_table, m_ref, newvalue); else throw emu_fatalerror("Symbol '%s' is read-only", m_name.c_str()); } //------------------------------------------------- // internal_getter - internal helper for // returning the value of a variable //------------------------------------------------- UINT64 integer_symbol_entry::internal_getter(symbol_table &table, void *symref) { return *(UINT64 *)symref; } //------------------------------------------------- // internal_setter - internal helper for setting // the value of a variable //------------------------------------------------- void integer_symbol_entry::internal_setter(symbol_table &table, void *symref, UINT64 value) { *(UINT64 *)symref = value; } //************************************************************************** // FUNCTION SYMBOL ENTRY //************************************************************************** //------------------------------------------------- // function_symbol_entry - constructor //------------------------------------------------- function_symbol_entry::function_symbol_entry(symbol_table &table, const char *name, void *ref, int minparams, int maxparams, symbol_table::execute_func execute) : symbol_entry(table, SMT_FUNCTION, name, ref), m_minparams(minparams), m_maxparams(maxparams), m_execute(execute) { } //------------------------------------------------- // is_lval - is this symbol allowable as an lval? //------------------------------------------------- bool function_symbol_entry::is_lval() const { return false; } //------------------------------------------------- // value - return the value of this symbol //------------------------------------------------- UINT64 function_symbol_entry::value() const { throw emu_fatalerror("Symbol '%s' is a function and cannot be used in this context", m_name.c_str()); } //------------------------------------------------- // set_value - set the value of this symbol //------------------------------------------------- void function_symbol_entry::set_value(UINT64 newvalue) { throw emu_fatalerror("Symbol '%s' is a function and cannot be written", m_name.c_str()); } //------------------------------------------------- // execute - execute the function //------------------------------------------------- UINT64 function_symbol_entry::execute(int numparams, const UINT64 *paramlist) { if (numparams < m_minparams) throw emu_fatalerror("Function '%s' requires at least %d parameters", m_name.c_str(), m_minparams); if (numparams > m_maxparams) throw emu_fatalerror("Function '%s' accepts no more than %d parameters", m_name.c_str(), m_maxparams); return (*m_execute)(m_table, m_ref, numparams, paramlist); } //************************************************************************** // SYMBOL TABLE //************************************************************************** //------------------------------------------------- // symbol_table - constructor //------------------------------------------------- symbol_table::symbol_table(void *globalref, symbol_table *parent) : m_parent(parent), m_globalref(globalref), m_memory_param(NULL), m_memory_valid(NULL), m_memory_read(NULL), m_memory_write(NULL) { } //------------------------------------------------- // add - add a new UINT64 pointer symbol //------------------------------------------------- void symbol_table::configure_memory(void *param, valid_func valid, read_func read, write_func write) { m_memory_param = param; m_memory_valid = valid; m_memory_read = read; m_memory_write = write; } //------------------------------------------------- // add - add a new UINT64 pointer symbol //------------------------------------------------- void symbol_table::add(const char *name, read_write rw, UINT64 *ptr) { m_symlist.remove(name); m_symlist.append(name, *global_alloc(integer_symbol_entry(*this, name, rw, ptr))); } //------------------------------------------------- // add - add a new value symbol //------------------------------------------------- void symbol_table::add(const char *name, UINT64 value) { m_symlist.remove(name); m_symlist.append(name, *global_alloc(integer_symbol_entry(*this, name, value))); } //------------------------------------------------- // add - add a new register symbol //------------------------------------------------- void symbol_table::add(const char *name, void *ref, getter_func getter, setter_func setter) { m_symlist.remove(name); m_symlist.append(name, *global_alloc(integer_symbol_entry(*this, name, ref, getter, setter))); } //------------------------------------------------- // add - add a new function symbol //------------------------------------------------- void symbol_table::add(const char *name, void *ref, int minparams, int maxparams, execute_func execute) { m_symlist.remove(name); m_symlist.append(name, *global_alloc(function_symbol_entry(*this, name, ref, minparams, maxparams, execute))); } //------------------------------------------------- // find_deep - do a deep search for a symbol, // looking in the parent if needed //------------------------------------------------- symbol_entry *symbol_table::find_deep(const char *symbol) { // walk up the table hierarchy to find the owner for (symbol_table *symtable = this; symtable != NULL; symtable = symtable->m_parent) { symbol_entry *entry = symtable->find(symbol); if (entry != NULL) return entry; } return NULL; } //------------------------------------------------- // value - return the value of a symbol //------------------------------------------------- UINT64 symbol_table::value(const char *symbol) { symbol_entry *entry = find_deep(symbol); return (entry != NULL) ? entry->value() : 0; } //------------------------------------------------- // set_value - set the value of a symbol //------------------------------------------------- void symbol_table::set_value(const char *symbol, UINT64 value) { symbol_entry *entry = find_deep(symbol); if (entry != NULL) entry->set_value(value); } //------------------------------------------------- // memory_valid - return true if the given // memory name/space/offset combination is valid //------------------------------------------------- expression_error::error_code symbol_table::memory_valid(const char *name, expression_space space) { // walk up the table hierarchy to find the owner for (symbol_table *symtable = this; symtable != NULL; symtable = symtable->m_parent) if (symtable->m_memory_valid != NULL) { expression_error::error_code err = (*symtable->m_memory_valid)(symtable->m_memory_param, name, space); if (err != expression_error::NO_SUCH_MEMORY_SPACE) return err; } return expression_error::NO_SUCH_MEMORY_SPACE; } //------------------------------------------------- // memory_value - return a value read from memory //------------------------------------------------- UINT64 symbol_table::memory_value(const char *name, expression_space space, UINT32 offset, int size) { // walk up the table hierarchy to find the owner for (symbol_table *symtable = this; symtable != NULL; symtable = symtable->m_parent) if (symtable->m_memory_valid != NULL) { expression_error::error_code err = (*symtable->m_memory_valid)(symtable->m_memory_param, name, space); if (err != expression_error::NO_SUCH_MEMORY_SPACE && symtable->m_memory_read != NULL) return (*symtable->m_memory_read)(symtable->m_memory_param, name, space, offset, size); return 0; } return 0; } //------------------------------------------------- // set_memory_value - write a value to memory //------------------------------------------------- void symbol_table::set_memory_value(const char *name, expression_space space, UINT32 offset, int size, UINT64 value) { // walk up the table hierarchy to find the owner for (symbol_table *symtable = this; symtable != NULL; symtable = symtable->m_parent) if (symtable->m_memory_valid != NULL) { expression_error::error_code err = (*symtable->m_memory_valid)(symtable->m_memory_param, name, space); if (err != expression_error::NO_SUCH_MEMORY_SPACE && symtable->m_memory_write != NULL) (*symtable->m_memory_write)(symtable->m_memory_param, name, space, offset, size, value); return; } } //************************************************************************** // PARSED EXPRESSION //************************************************************************** //------------------------------------------------- // parsed_expression - constructor //------------------------------------------------- parsed_expression::parsed_expression(symbol_table *symtable, const char *expression, UINT64 *result) : m_symtable(symtable), m_token_stack_ptr(0) { // if we got an expression parse it if (expression != NULL) parse(expression); // if we get a result pointer, execute it if (result != NULL) *result = execute(); } //------------------------------------------------- // parse - parse an expression into tokens //------------------------------------------------- void parsed_expression::parse(const char *expression) { // copy the string and reset our parsing state m_original_string.assign(expression); m_tokenlist.reset(); m_stringlist.reset(); // first parse the tokens into the token array in order parse_string_into_tokens(); // convert the infix order to postfix order infix_to_postfix(); } //------------------------------------------------- // copy - copy an expression from another source //------------------------------------------------- void parsed_expression::copy(const parsed_expression &src) { m_symtable = src.m_symtable; m_original_string.assign(src.m_original_string); if (!m_original_string.empty()) parse_string_into_tokens(); } //------------------------------------------------- // print_tokens - debugging took to print a // human readable token representation //------------------------------------------------- void parsed_expression::print_tokens(FILE *out) { #if DEBUG_TOKENS osd_printf_debug("----\n"); for (parse_token *token = m_tokens.first(); token != NULL; token = token->next()) { switch (token->type) { default: case parse_token::INVALID: fprintf(out, "INVALID\n"); break; case parse_token::END: fprintf(out, "END\n"); break; case parse_token::NUMBER: fprintf(out, "NUMBER: %08X%08X\n", (UINT32)(token->value.i >> 32), (UINT32)token->value.i); break; case parse_token::STRING: fprintf(out, "STRING: ""%s""\n", token->string); break; case parse_token::SYMBOL: fprintf(out, "SYMBOL: %08X%08X\n", (UINT32)(token->value.i >> 32), (UINT32)token->value.i); break; case parse_token::OPERATOR: switch (token->value.i) { case TVL_LPAREN: fprintf(out, "(\n"); break; case TVL_RPAREN: fprintf(out, ")\n"); break; case TVL_PLUSPLUS: fprintf(out, "++ (unspecified)\n"); break; case TVL_MINUSMINUS: fprintf(out, "-- (unspecified)\n"); break; case TVL_PREINCREMENT: fprintf(out, "++ (prefix)\n"); break; case TVL_PREDECREMENT: fprintf(out, "-- (prefix)\n"); break; case TVL_POSTINCREMENT: fprintf(out, "++ (postfix)\n"); break; case TVL_POSTDECREMENT: fprintf(out, "-- (postfix)\n"); break; case TVL_COMPLEMENT: fprintf(out, "!\n"); break; case TVL_NOT: fprintf(out, "~\n"); break; case TVL_UPLUS: fprintf(out, "+ (unary)\n"); break; case TVL_UMINUS: fprintf(out, "- (unary)\n"); break; case TVL_MULTIPLY: fprintf(out, "*\n"); break; case TVL_DIVIDE: fprintf(out, "/\n"); break; case TVL_MODULO: fprintf(out, "%%\n"); break; case TVL_ADD: fprintf(out, "+\n"); break; case TVL_SUBTRACT: fprintf(out, "-\n"); break; case TVL_LSHIFT: fprintf(out, "<<\n"); break; case TVL_RSHIFT: fprintf(out, ">>\n"); break; case TVL_LESS: fprintf(out, "<\n"); break; case TVL_LESSOREQUAL: fprintf(out, "<=\n"); break; case TVL_GREATER: fprintf(out, ">\n"); break; case TVL_GREATEROREQUAL:fprintf(out, ">=\n"); break; case TVL_EQUAL: fprintf(out, "==\n"); break; case TVL_NOTEQUAL: fprintf(out, "!=\n"); break; case TVL_BAND: fprintf(out, "&\n"); break; case TVL_BXOR: fprintf(out, "^\n"); break; case TVL_BOR: fprintf(out, "|\n"); break; case TVL_LAND: fprintf(out, "&&\n"); break; case TVL_LOR: fprintf(out, "||\n"); break; case TVL_ASSIGN: fprintf(out, "=\n"); break; case TVL_ASSIGNMULTIPLY:fprintf(out, "*=\n"); break; case TVL_ASSIGNDIVIDE: fprintf(out, "/=\n"); break; case TVL_ASSIGNMODULO: fprintf(out, "%%=\n"); break; case TVL_ASSIGNADD: fprintf(out, "+=\n"); break; case TVL_ASSIGNSUBTRACT:fprintf(out, "-=\n"); break; case TVL_ASSIGNLSHIFT: fprintf(out, "<<=\n"); break; case TVL_ASSIGNRSHIFT: fprintf(out, ">>=\n"); break; case TVL_ASSIGNBAND: fprintf(out, "&=\n"); break; case TVL_ASSIGNBXOR: fprintf(out, "^=\n"); break; case TVL_ASSIGNBOR: fprintf(out, "|=\n"); break; case TVL_COMMA: fprintf(out, ",\n"); break; case TVL_MEMORYAT: fprintf(out, "mem@\n"); break; case TVL_EXECUTEFUNC: fprintf(out, "execute\n"); break; default: fprintf(out, "INVALID OPERATOR\n"); break; } break; } } osd_printf_debug("----\n"); #endif } //------------------------------------------------- // parse_string_into_tokens - take an expression // string and break it into a sequence of tokens //------------------------------------------------- void parsed_expression::parse_string_into_tokens() { // loop until done const char *stringstart = m_original_string.c_str(); const char *string = stringstart; while (string[0] != 0) { // ignore any whitespace while (string[0] != 0 && isspace((UINT8)string[0])) string++; if (string[0] == 0) break; // initialize the current token object parse_token &token = m_tokenlist.append(*global_alloc(parse_token(string - stringstart))); // switch off the first character switch (tolower((UINT8)string[0])) { case '(': string += 1, token.configure_operator(TVL_LPAREN, 0); break; case ')': string += 1, token.configure_operator(TVL_RPAREN, 0); break; case '~': string += 1, token.configure_operator(TVL_NOT, 2); break; case ',': string += 1, token.configure_operator(TVL_COMMA, 14); break; case '+': if (string[1] == '+') string += 2, token.configure_operator(TVL_PLUSPLUS, 1); else if (string[1] == '=') string += 2, token.configure_operator(TVL_ASSIGNADD, 13).set_right_to_left(); else string += 1, token.configure_operator(TVL_ADD, 4); break; case '-': if (string[1] == '-') string += 2, token.configure_operator(TVL_MINUSMINUS, 1); else if (string[1] == '=') string += 2, token.configure_operator(TVL_ASSIGNSUBTRACT, 13).set_right_to_left(); else string += 1, token.configure_operator(TVL_SUBTRACT, 4); break; case '*': if (string[1] == '=') string += 2, token.configure_operator(TVL_ASSIGNMULTIPLY, 13).set_right_to_left(); else string += 1, token.configure_operator(TVL_MULTIPLY, 3); break; case '/': if (string[1] == '=') string += 2, token.configure_operator(TVL_ASSIGNDIVIDE, 13).set_right_to_left(); else string += 1, token.configure_operator(TVL_DIVIDE, 3); break; case '%': if (string[1] == '=') string += 2, token.configure_operator(TVL_ASSIGNMODULO, 13).set_right_to_left(); else string += 1, token.configure_operator(TVL_MODULO, 3); break; case '<': if (string[1] == '<' && string[2] == '=') string += 3, token.configure_operator(TVL_ASSIGNLSHIFT, 13).set_right_to_left(); else if (string[1] == '<') string += 2, token.configure_operator(TVL_LSHIFT, 5); else if (string[1] == '=') string += 2, token.configure_operator(TVL_LESSOREQUAL, 6); else string += 1, token.configure_operator(TVL_LESS, 6); break; case '>': if (string[1] == '>' && string[2] == '=') string += 3, token.configure_operator(TVL_ASSIGNRSHIFT, 13).set_right_to_left(); else if (string[1] == '>') string += 2, token.configure_operator(TVL_RSHIFT, 5); else if (string[1] == '=') string += 2, token.configure_operator(TVL_GREATEROREQUAL, 6); else string += 1, token.configure_operator(TVL_GREATER, 6); break; case '=': if (string[1] == '=') string += 2, token.configure_operator(TVL_EQUAL, 7); else string += 1, token.configure_operator(TVL_ASSIGN, 13).set_right_to_left(); break; case '!': if (string[1] == '=') string += 2, token.configure_operator(TVL_NOTEQUAL, 7); else string += 2, token.configure_operator(TVL_COMPLEMENT, 2); break; case '&': if (string[1] == '&') string += 2, token.configure_operator(TVL_LAND, 11); else if (string[1] == '=') string += 2, token.configure_operator(TVL_ASSIGNBAND, 13).set_right_to_left(); else string += 1, token.configure_operator(TVL_BAND, 8); break; case '|': if (string[1] == '|') string += 2, token.configure_operator(TVL_LOR, 12); else if (string[1] == '=') string += 2, token.configure_operator(TVL_ASSIGNBOR, 13).set_right_to_left(); else string += 1, token.configure_operator(TVL_BOR, 10); break; case '^': if (string[1] == '=') string += 2, token.configure_operator(TVL_ASSIGNBXOR, 13).set_right_to_left(); else string += 1, token.configure_operator(TVL_BXOR, 9); break; case '"': parse_quoted_string(token, string); break; case '\'': parse_quoted_char(token, string); break; default: parse_symbol_or_number(token, string); break; } } } //------------------------------------------------- // parse_symbol_or_number - parse a substring // into either a symbol or a number or an // expanded operator //------------------------------------------------- void parsed_expression::parse_symbol_or_number(parse_token &token, const char *&string) { // accumulate a lower-case version of the symbol const char *stringstart = string; std::string buffer; while (1) { static const char valid[] = "abcdefghijklmnopqrstuvwxyz0123456789_$#.:"; char val = tolower((UINT8)string[0]); if (val == 0 || strchr(valid, val) == NULL) break; buffer.append(&val, 1); string++; } // check for memory @ operators if (string[0] == '@') { string += 1; return parse_memory_operator(token, buffer.c_str()); } // empty string is automatically invalid if (buffer.empty()) throw expression_error(expression_error::INVALID_TOKEN, token.offset()); // check for wordy variants on standard operators if (buffer.compare("bnot")==0) { token.configure_operator(TVL_NOT, 2); return; } if (buffer.compare("plus") == 0) { token.configure_operator(TVL_ADD, 4); return; } if (buffer.compare("minus") == 0) { token.configure_operator(TVL_SUBTRACT, 4); return; } if (buffer.compare("times") == 0 || buffer.compare("mul") == 0) { token.configure_operator(TVL_MULTIPLY, 3); return; } if (buffer.compare("div") == 0) { token.configure_operator(TVL_DIVIDE, 3); return; } if (buffer.compare("mod") == 0) { token.configure_operator(TVL_MODULO, 3); return; } if (buffer.compare("lt") == 0) { token.configure_operator(TVL_LESS, 6); return; } if (buffer.compare("le") == 0) { token.configure_operator(TVL_LESSOREQUAL, 6); return; } if (buffer.compare("gt") == 0) { token.configure_operator(TVL_GREATER, 6); return; } if (buffer.compare("ge") == 0) { token.configure_operator(TVL_GREATEROREQUAL, 6); return; } if (buffer.compare("eq") == 0) { token.configure_operator(TVL_EQUAL, 7); return; } if (buffer.compare("ne") == 0) { token.configure_operator(TVL_NOTEQUAL, 7); return; } if (buffer.compare("not") == 0) { token.configure_operator(TVL_COMPLEMENT, 2); return; } if (buffer.compare("and") == 0) { token.configure_operator(TVL_LAND, 8); return; } if (buffer.compare("band") == 0) { token.configure_operator(TVL_BAND, 8); return; } if (buffer.compare("or") == 0) { token.configure_operator(TVL_LOR, 12); return; } if (buffer.compare("bor") == 0) { token.configure_operator(TVL_BOR, 10); return; } if (buffer.compare("bxor") == 0) { token.configure_operator(TVL_BXOR, 9); return; } if (buffer.compare("lshift") == 0) { token.configure_operator(TVL_LSHIFT, 5); return; } if (buffer.compare("rshift") == 0) { token.configure_operator(TVL_RSHIFT, 5); return; } // if we have an 0x prefix, we must be a hex value if (buffer[0] == '0' && buffer[1] == 'x') return parse_number(token, buffer.c_str() + 2, 16, expression_error::INVALID_NUMBER); // if we have a # prefix, we must be a decimal value if (buffer[0] == '#') return parse_number(token, buffer.c_str() + 1, 10, expression_error::INVALID_NUMBER); // if we have a $ prefix, we are a hex value if (buffer[0] == '$') return parse_number(token, buffer.c_str() + 1, 16, expression_error::INVALID_NUMBER); // check for a symbol match symbol_entry *symbol = m_symtable->find_deep(buffer.c_str()); if (symbol != NULL) { token.configure_symbol(*symbol); // if this is a function symbol, synthesize an execute function operator if (symbol->is_function()) { parse_token &newtoken = m_tokenlist.append(*global_alloc(parse_token(string - stringstart))); newtoken.configure_operator(TVL_EXECUTEFUNC, 0); } return; } // attempt to parse as a number in the default base parse_number(token, buffer.c_str(), DEFAULT_BASE, expression_error::UNKNOWN_SYMBOL); } //------------------------------------------------- // parse_number - parse a number using the // given base //------------------------------------------------- void parsed_expression::parse_number(parse_token &token, const char *string, int base, expression_error::error_code errcode) { // parse the actual value UINT64 value = 0; while (*string != 0) { // look up the number's value, stopping if not valid static const char numbers[] = "0123456789abcdef"; const char *ptr = strchr(numbers, tolower((UINT8)*string)); if (ptr == NULL) break; // if outside of the base, we also stop int digit = ptr - numbers; if (digit >= base) break; // shift previous digits up and add in new digit value = (value * (UINT64)base) + digit; string++; } // if we succeeded as a number, make it so if (*string == 0) token.configure_number(value); else throw expression_error(errcode, token.offset()); } //------------------------------------------------- // parse_quoted_char - parse a single-quoted // character constant //------------------------------------------------- void parsed_expression::parse_quoted_char(parse_token &token, const char *&string) { // accumulate the value of the character token string++; UINT64 value = 0; while (string[0] != 0) { // allow '' to mean a nested single quote if (string[0] == '\'') { if (string[1] != '\'') break; string++; } value = (value << 8) | (UINT8)*string++; } // if we didn't find the ending quote, report an error if (string[0] != '\'') throw expression_error(expression_error::UNBALANCED_QUOTES, token.offset()); string++; // make it a number token token.configure_number(value); } //------------------------------------------------- // parse_quoted_string - parse a double-quoted // string constant //------------------------------------------------- void parsed_expression::parse_quoted_string(parse_token &token, const char *&string) { // accumulate a copy of the quoted string string++; std::string buffer; while (string[0] != 0) { // allow "" to mean a nested double-quote if (string[0] == '"') { if (string[1] != '"') break; string++; } buffer.append(string++, 1); } // if we didn't find the ending quote, report an error if (string[0] != '"') throw expression_error(expression_error::UNBALANCED_QUOTES, token.offset()); string++; // make the token token.configure_string(m_stringlist.append(*global_alloc(expression_string(buffer.c_str())))); } //------------------------------------------------- // parse_memory_operator - parse the several // forms of memory operators //------------------------------------------------- void parsed_expression::parse_memory_operator(parse_token &token, const char *string) { // if there is a '.', it means we have a name const char *startstring = string; const char *namestring = NULL; const char *dot = strrchr(string, '.'); if (dot != NULL) { namestring = m_stringlist.append(*global_alloc(expression_string(string, dot - string))); string = dot + 1; } // length 3 means logical/physical, then space, then size int length = (int)strlen(string); bool physical = false; int space = 'p'; int size; if (length == 3) { if (string[0] != 'l' && string[0] != 'p') throw expression_error(expression_error::INVALID_MEMORY_SPACE, token.offset() + (string - startstring)); if (string[1] != 'p' && string[1] != 'd' && string[1] != 'i' && string[1] != '3') throw expression_error(expression_error::INVALID_MEMORY_SPACE, token.offset() + (string - startstring)); physical = (string[0] == 'p'); space = string[1]; size = string[2]; } // length 2 means space then size else if (length == 2) { space = string[0]; size = string[1]; } // length 1 means size else if (length == 1) size = string[0]; // anything else is invalid else throw expression_error(expression_error::INVALID_TOKEN, token.offset()); // convert the space to flags expression_space memspace = EXPSPACE_INVALID; switch (space) { case 'p': memspace = physical ? EXPSPACE_PROGRAM_PHYSICAL : EXPSPACE_PROGRAM_LOGICAL; break; case 'd': memspace = physical ? EXPSPACE_DATA_PHYSICAL : EXPSPACE_DATA_LOGICAL; break; case 'i': memspace = physical ? EXPSPACE_IO_PHYSICAL : EXPSPACE_IO_LOGICAL; break; case '3': memspace = physical ? EXPSPACE_SPACE3_PHYSICAL : EXPSPACE_SPACE3_LOGICAL; break; case 'o': memspace = EXPSPACE_OPCODE; break; case 'r': memspace = EXPSPACE_RAMWRITE; break; case 'm': memspace = EXPSPACE_REGION; break; default: throw expression_error(expression_error::INVALID_MEMORY_SPACE, token.offset() + (string - startstring)); } // convert the size to flags int memsize; switch (size) { case 'b': memsize = 0; break; case 'w': memsize = 1; break; case 'd': memsize = 2; break; case 'q': memsize = 3; break; default: throw expression_error(expression_error::INVALID_MEMORY_SIZE, token.offset() + (string - startstring) + length - 1); } // validate the name if (m_symtable != NULL) { expression_error::error_code err = m_symtable->memory_valid(namestring, memspace); if (err != expression_error::NONE) throw expression_error(err, token.offset() + (string - startstring)); } // configure the token token.configure_operator(TVL_MEMORYAT, 2).set_memory_size(memsize).set_memory_space(memspace).set_memory_source(namestring); } //------------------------------------------------- // normalize_operator - resolve operator // ambiguities based on neighboring tokens //------------------------------------------------- void parsed_expression::normalize_operator(parse_token *prevtoken, parse_token &thistoken) { parse_token *nexttoken = thistoken.next(); switch (thistoken.optype()) { // Determine if an open paren is part of a function or not case TVL_LPAREN: if (prevtoken != NULL && prevtoken->is_operator(TVL_EXECUTEFUNC)) thistoken.set_function_separator(); break; // Determine if ++ is a pre or post increment case TVL_PLUSPLUS: if (nexttoken != NULL && (nexttoken->is_symbol() || (nexttoken->is_operator(TVL_MEMORYAT)))) thistoken.configure_operator(TVL_PREINCREMENT, 2); else if (prevtoken != NULL && (prevtoken->is_symbol() || (prevtoken->is_operator(TVL_MEMORYAT)))) thistoken.configure_operator(TVL_POSTINCREMENT, 1); else throw expression_error(expression_error::SYNTAX, thistoken.offset()); break; // Determine if -- is a pre or post decrement case TVL_MINUSMINUS: if (nexttoken != NULL && (nexttoken->is_symbol() || (nexttoken->is_operator(TVL_MEMORYAT)))) thistoken.configure_operator(TVL_PREDECREMENT, 2); else if (prevtoken != NULL && (prevtoken->is_symbol() || (prevtoken->is_operator(TVL_MEMORYAT)))) thistoken.configure_operator(TVL_POSTDECREMENT, 1); else throw expression_error(expression_error::SYNTAX, thistoken.offset()); break; // Determine if +/- is a unary or binary case TVL_ADD: case TVL_SUBTRACT: // Assume we're unary if we are the first token, or if the previous token is not // a symbol, a number, or a right parenthesis if (prevtoken == NULL || (!prevtoken->is_symbol() && !prevtoken->is_number() && !prevtoken->is_operator(TVL_RPAREN))) thistoken.configure_operator(thistoken.is_operator(TVL_ADD) ? TVL_UPLUS : TVL_UMINUS, 2); break; // Determine if , refers to a function parameter case TVL_COMMA: for (int lookback = 0; lookback < MAX_STACK_DEPTH; lookback++) { parse_token *peek = peek_token(lookback); if (peek == NULL) break; // if we hit an execute function operator, or else a left parenthesis that is // already tagged, then tag us as well if (peek->is_operator(TVL_EXECUTEFUNC) || (peek->is_operator(TVL_LPAREN) && peek->is_function_separator())) { thistoken.set_function_separator(); break; } } break; } } //------------------------------------------------- // infix_to_postfix - convert an infix sequence // of tokens to a postfix sequence for processing //------------------------------------------------- void parsed_expression::infix_to_postfix() { simple_list stack; // loop over all the original tokens parse_token *prev = NULL; parse_token *next = NULL; for (parse_token *token = m_tokenlist.detach_all(); token != NULL; prev = token, token = next) { // pre-determine our next token next = token->next(); // if the character is an operand, append it to the result string if (token->is_number() || token->is_symbol() || token->is_string()) m_tokenlist.append(*token); // if this is an operator, process it else if (token->is_operator()) { // normalize the operator based on neighbors normalize_operator(prev, *token); // if the token is an opening parenthesis, push it onto the stack. if (token->is_operator(TVL_LPAREN)) stack.prepend(*token); // if the token is a closing parenthesis, pop all operators until we // reach an opening parenthesis and append them to the result string, // discaring the open parenthesis else if (token->is_operator(TVL_RPAREN)) { // loop until we find our matching opener parse_token *popped; while ((popped = stack.detach_head()) != NULL) { if (popped->is_operator(TVL_LPAREN)) break; m_tokenlist.append(*popped); } // if we didn't find an open paren, it's an error if (popped == NULL) throw expression_error(expression_error::UNBALANCED_PARENS, token->offset()); // free ourself and our matching opening parenthesis global_free(token); global_free(popped); } // if the token is an operator, pop operators until we reach an opening parenthesis, // an operator of lower precedence, or a right associative symbol of equal precedence. // Push the operator onto the stack. else { int our_precedence = token->precedence(); // loop until we can't peek at the stack anymore parse_token *peek; while ((peek = stack.first()) != NULL) { // break if any of the above conditions are true if (peek->is_operator(TVL_LPAREN)) break; int stack_precedence = peek->precedence(); if (stack_precedence > our_precedence || (stack_precedence == our_precedence && peek->right_to_left())) break; // pop this token m_tokenlist.append(*stack.detach_head()); } // push the new operator stack.prepend(*token); } } } // finish popping the stack parse_token *popped; while ((popped = stack.detach_head()) != NULL) { // it is an error to have a left parenthesis still on the stack if (popped->is_operator(TVL_LPAREN)) throw expression_error(expression_error::UNBALANCED_PARENS, popped->offset()); // pop this token m_tokenlist.append(*popped); } } //------------------------------------------------- // push_token - push a token onto the stack //------------------------------------------------- inline void parsed_expression::push_token(parse_token &token) { // check for overflow if (m_token_stack_ptr >= MAX_STACK_DEPTH) throw expression_error(expression_error::STACK_OVERFLOW, token.offset()); // push m_token_stack[m_token_stack_ptr++] = token; } //------------------------------------------------- // pop_token - pop a token off the stack //------------------------------------------------- inline void parsed_expression::pop_token(parse_token &token) { // check for underflow if (m_token_stack_ptr == 0) throw expression_error(expression_error::STACK_UNDERFLOW, token.offset()); // pop token = m_token_stack[--m_token_stack_ptr]; } //------------------------------------------------- // peek_token - look at a token some number of // entries up the stack //------------------------------------------------- inline parsed_expression::parse_token *parsed_expression::peek_token(int count) { if (m_token_stack_ptr <= count) return NULL; return &m_token_stack[m_token_stack_ptr - count - 1]; } //------------------------------------------------- // pop_token_lval - pop a token off the stack // and ensure that it is a proper lval //------------------------------------------------- inline void parsed_expression::pop_token_lval(parse_token &token) { // start with normal pop pop_token(token); // if we're not an lval, throw an error if (!token.is_lval()) throw expression_error(expression_error::NOT_LVAL, token.offset()); } //------------------------------------------------- // pop_token_rval - pop a token off the stack // and ensure that it is a proper rval //------------------------------------------------- inline void parsed_expression::pop_token_rval(parse_token &token) { // start with normal pop pop_token(token); // symbol and memory tokens get resolved down to number tokens if (token.is_symbol() || token.is_memory()) token.configure_number(token.get_lval_value(m_symtable)); // to be an rval, the final token must be a number if (!token.is_number()) throw expression_error(expression_error::NOT_RVAL, token.offset()); } //------------------------------------------------- // execute_tokens - execute a postfix sequence // of tokens //------------------------------------------------- UINT64 parsed_expression::execute_tokens() { // reset the token stack m_token_stack_ptr = 0; // loop over the entire sequence parse_token t1, t2, result; for (parse_token *token = m_tokenlist.first(); token != NULL; token = token->next()) { // symbols/numbers/strings just get pushed if (!token->is_operator()) { push_token(*token); continue; } // otherwise, switch off the operator switch (token->optype()) { case TVL_PREINCREMENT: pop_token_lval(t1); push_token(result.configure_number(t1.get_lval_value(m_symtable) + 1).set_offset(t1)); t1.set_lval_value(m_symtable, result.value()); break; case TVL_PREDECREMENT: pop_token_lval(t1); push_token(result.configure_number(t1.get_lval_value(m_symtable) - 1).set_offset(t1)); t1.set_lval_value(m_symtable, result.value()); break; case TVL_POSTINCREMENT: pop_token_lval(t1); push_token(result.configure_number(t1.get_lval_value(m_symtable)).set_offset(t1)); t1.set_lval_value(m_symtable, result.value() + 1); break; case TVL_POSTDECREMENT: pop_token_lval(t1); push_token(result.configure_number(t1.get_lval_value(m_symtable)).set_offset(t1)); t1.set_lval_value(m_symtable, result.value() - 1); break; case TVL_COMPLEMENT: pop_token_rval(t1); push_token(result.configure_number(!t1.value()).set_offset(t1)); break; case TVL_NOT: pop_token_rval(t1); push_token(result.configure_number(~t1.value()).set_offset(t1)); break; case TVL_UPLUS: pop_token_rval(t1); push_token(result.configure_number(t1.value()).set_offset(t1)); break; case TVL_UMINUS: pop_token_rval(t1); push_token(result.configure_number(-t1.value()).set_offset(t1)); break; case TVL_MULTIPLY: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() * t2.value()).set_offset(t1, t2)); break; case TVL_DIVIDE: pop_token_rval(t2); pop_token_rval(t1); if (t2.value() == 0) throw expression_error(expression_error::DIVIDE_BY_ZERO, t2.offset()); push_token(result.configure_number(t1.value() / t2.value()).set_offset(t1, t2)); break; case TVL_MODULO: pop_token_rval(t2); pop_token_rval(t1); if (t2.value() == 0) throw expression_error(expression_error::DIVIDE_BY_ZERO, t2.offset()); push_token(result.configure_number(t1.value() % t2.value()).set_offset(t1, t2)); break; case TVL_ADD: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() + t2.value()).set_offset(t1, t2)); break; case TVL_SUBTRACT: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() - t2.value()).set_offset(t1, t2)); break; case TVL_LSHIFT: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() << t2.value()).set_offset(t1, t2)); break; case TVL_RSHIFT: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() >> t2.value()).set_offset(t1, t2)); break; case TVL_LESS: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() < t2.value()).set_offset(t1, t2)); break; case TVL_LESSOREQUAL: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() <= t2.value()).set_offset(t1, t2)); break; case TVL_GREATER: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() > t2.value()).set_offset(t1, t2)); break; case TVL_GREATEROREQUAL: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() >= t2.value()).set_offset(t1, t2)); break; case TVL_EQUAL: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() == t2.value()).set_offset(t1, t2)); break; case TVL_NOTEQUAL: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() != t2.value()).set_offset(t1, t2)); break; case TVL_BAND: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() & t2.value()).set_offset(t1, t2)); break; case TVL_BXOR: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() ^ t2.value()).set_offset(t1, t2)); break; case TVL_BOR: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() | t2.value()).set_offset(t1, t2)); break; case TVL_LAND: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() && t2.value()).set_offset(t1, t2)); break; case TVL_LOR: pop_token_rval(t2); pop_token_rval(t1); push_token(result.configure_number(t1.value() || t2.value()).set_offset(t1, t2)); break; case TVL_ASSIGN: pop_token_rval(t2); pop_token_lval(t1); push_token(result.configure_number(t2.value()).set_offset(t2)); t1.set_lval_value(m_symtable, t2.value()); break; case TVL_ASSIGNMULTIPLY: pop_token_rval(t2); pop_token_lval(t1); push_token(result.configure_number(t1.get_lval_value(m_symtable) * t2.value()).set_offset(t1, t2)); t1.set_lval_value(m_symtable, result.value()); break; case TVL_ASSIGNDIVIDE: pop_token_rval(t2); pop_token_lval(t1); if (t2.value() == 0) throw expression_error(expression_error::DIVIDE_BY_ZERO, t2.offset()); push_token(result.configure_number(t1.get_lval_value(m_symtable) / t2.value()).set_offset(t1, t2)); t1.set_lval_value(m_symtable, result.value()); break; case TVL_ASSIGNMODULO: pop_token_rval(t2); pop_token_lval(t1); if (t2.value() == 0) throw expression_error(expression_error::DIVIDE_BY_ZERO, t2.offset()); push_token(result.configure_number(t1.get_lval_value(m_symtable) % t2.value()).set_offset(t1, t2)); t1.set_lval_value(m_symtable, result.value()); break; case TVL_ASSIGNADD: pop_token_rval(t2); pop_token_lval(t1); push_token(result.configure_number(t1.get_lval_value(m_symtable) + t2.value()).set_offset(t1, t2)); t1.set_lval_value(m_symtable, result.value()); break; case TVL_ASSIGNSUBTRACT: pop_token_rval(t2); pop_token_lval(t1); push_token(result.configure_number(t1.get_lval_value(m_symtable) - t2.value()).set_offset(t1, t2)); t1.set_lval_value(m_symtable, result.value()); break; case TVL_ASSIGNLSHIFT: pop_token_rval(t2); pop_token_lval(t1); push_token(result.configure_number(t1.get_lval_value(m_symtable) << t2.value()).set_offset(t1, t2)); t1.set_lval_value(m_symtable, result.value()); break; case TVL_ASSIGNRSHIFT: pop_token_rval(t2); pop_token_lval(t1); push_token(result.configure_number(t1.get_lval_value(m_symtable) >> t2.value()).set_offset(t1, t2)); t1.set_lval_value(m_symtable, result.value()); break; case TVL_ASSIGNBAND: pop_token_rval(t2); pop_token_lval(t1); push_token(result.configure_number(t1.get_lval_value(m_symtable) & t2.value()).set_offset(t1, t2)); t1.set_lval_value(m_symtable, result.value()); break; case TVL_ASSIGNBXOR: pop_token_rval(t2); pop_token_lval(t1); push_token(result.configure_number(t1.get_lval_value(m_symtable) ^ t2.value()).set_offset(t1, t2)); t1.set_lval_value(m_symtable, result.value()); break; case TVL_ASSIGNBOR: pop_token_rval(t2); pop_token_lval(t1); push_token(result.configure_number(t1.get_lval_value(m_symtable) | t2.value()).set_offset(t1, t2)); t1.set_lval_value(m_symtable, result.value()); break; case TVL_COMMA: if (!token->is_function_separator()) { pop_token_rval(t2); pop_token_rval(t1); push_token(t2); } break; case TVL_MEMORYAT: pop_token_rval(t1); push_token(result.configure_memory(t1.value(), *token)); break; case TVL_EXECUTEFUNC: execute_function(*token); break; default: throw expression_error(expression_error::SYNTAX, token->offset()); } } // pop the final result pop_token_rval(result); // error if our stack isn't empty if (peek_token(0) != NULL) throw expression_error(expression_error::SYNTAX, 0); return result.value(); } //************************************************************************** // PARSE TOKEN //************************************************************************** //------------------------------------------------- // parse_token - constructor //------------------------------------------------- parsed_expression::parse_token::parse_token(int offset) : m_next(NULL), m_type(INVALID), m_offset(offset), m_value(0), m_flags(0), m_string(NULL), m_symbol(NULL) { } //------------------------------------------------- // get_lval_value - call the getter function // for a SYMBOL token //------------------------------------------------- UINT64 parsed_expression::parse_token::get_lval_value(symbol_table *table) { // get the value of a symbol if (is_symbol()) return m_symbol->value(); // or get the value from the memory callbacks else if (is_memory() && table != NULL) return table->memory_value(m_string, memory_space(), address(), 1 << memory_size()); return 0; } //------------------------------------------------- // set_lval_value - call the setter function // for a SYMBOL token //------------------------------------------------- inline void parsed_expression::parse_token::set_lval_value(symbol_table *table, UINT64 value) { // set the value of a symbol if (is_symbol()) m_symbol->set_value(value); // or set the value via the memory callbacks else if (is_memory() && table != NULL) table->set_memory_value(m_string, memory_space(), address(), 1 << memory_size(), value); } //------------------------------------------------- // execute_function - handle an execute function // operator //------------------------------------------------- void parsed_expression::execute_function(parse_token &token) { // pop off all pushed parameters UINT64 funcparams[MAX_FUNCTION_PARAMS]; symbol_entry *symbol = NULL; int paramcount = 0; while (paramcount < MAX_FUNCTION_PARAMS) { // peek at the next token on the stack parse_token *peek = peek_token(0); if (peek == NULL) throw expression_error(expression_error::INVALID_PARAM_COUNT, token.offset()); // if it is a function symbol, break out of the loop if (peek->is_symbol()) { symbol = peek->symbol(); if (symbol->is_function()) { parse_token t1; pop_token(t1); break; } } // otherwise, pop as a standard rval parse_token t1; pop_token_rval(t1); funcparams[MAX_FUNCTION_PARAMS - (++paramcount)] = t1.value(); } // if we didn't find the symbol, fail if (paramcount == MAX_FUNCTION_PARAMS) throw expression_error(expression_error::INVALID_PARAM_COUNT, token.offset()); // execute the function and push the result function_symbol_entry *function = downcast(symbol); parse_token result(token.offset()); result.configure_number(function->execute(paramcount, &funcparams[MAX_FUNCTION_PARAMS - paramcount])); push_token(result); }