aicasm_gram.y

基于组件方式开发操作系统的OSKIT源代码

%{
/*
 * Parser for the Aic7xxx SCSI Host adapter sequencer assembler.
 *
 * Copyright (c) 1997-1998 Justin T. Gibbs.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification, immediately at the beginning of the file.
 * 2. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      $Id: aicasm_gram.y,v 1.6 1998/12/10 04:14:50 gibbs Exp $
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>

#include <sys/types.h>
#include <sys/queue.h>

#include "aicasm.h"
#include "aicasm_symbol.h"
#include "sequencer.h"

int yylineno;
char *yyfilename;
static symbol_t *cur_symbol;
static symtype cur_symtype;
static symbol_t *accumulator;
static symbol_ref_t allones;
static symbol_ref_t allzeros;
static symbol_ref_t none;
static symbol_ref_t sindex;
static int instruction_ptr;
static int sram_or_scb_offset;
static int download_constant_count;

static void process_bitmask __P((int mask_type, symbol_t *sym, int mask));
static void initialize_symbol __P((symbol_t *symbol));
static void process_register __P((symbol_t **p_symbol));
static void format_1_instr __P((int opcode, symbol_ref_t *dest,
				expression_t *immed, symbol_ref_t *src,
				int ret));
static void format_2_instr __P((int opcode, symbol_ref_t *dest,
				expression_t *places, symbol_ref_t *src,
				int ret));
static void format_3_instr __P((int opcode, symbol_ref_t *src,
				expression_t *immed, symbol_ref_t *address));
static void test_readable_symbol __P((symbol_t *symbol));
static void test_writable_symbol __P((symbol_t *symbol));
static void type_check __P((symbol_t *symbol, expression_t *expression,
			    int and_op));
static void make_expression __P((expression_t *immed, int value));
static void add_conditional __P((symbol_t *symbol));
static int  is_download_const __P((expression_t *immed));

#define YYDEBUG 1
#define SRAM_SYMNAME "SRAM_BASE"
#define SCB_SYMNAME "SCB_BASE"
%}

%union {
	int		value;
	char		*str;
	symbol_t	*sym;
	symbol_ref_t	sym_ref;
	expression_t	expression;
}

%token T_REGISTER

%token <value> T_CONST

%token T_DOWNLOAD

%token T_SCB

%token T_SRAM

%token T_ALIAS

%token T_SIZE

%token <value> T_ADDRESS

%token T_ACCESS_MODE

%token <value> T_MODE

%token T_BIT

%token T_MASK

%token <value> T_NUMBER

%token <str> T_PATH

%token <sym> T_CEXPR

%token T_EOF T_INCLUDE 

%token <value> T_SHR T_SHL T_ROR T_ROL

%token <value> T_MVI T_MOV T_CLR T_BMOV

%token <value> T_JMP T_JC T_JNC T_JE T_JNE T_JNZ T_JZ T_CALL

%token <value> T_ADD T_ADC

%token <value> T_INC T_DEC

%token <value> T_STC T_CLC

%token <value> T_CMP T_XOR

%token <value> T_TEST T_AND

%token <value> T_OR

%token T_RET

%token T_NOP

%token T_ACCUM T_ALLONES T_ALLZEROS T_NONE T_SINDEX

%token T_A

%token <sym> T_SYMBOL

%token T_NL

%token T_IF T_ELSE T_ELSE_IF T_ENDIF

%type <sym_ref> reg_symbol address destination source opt_source

%type <expression> expression immediate immediate_or_a

%type <value> ret f1_opcode f2_opcode jmp_jc_jnc_call jz_jnz je_jne

%type <value> numerical_value

%left '|'
%left '&'
%left '+' '-'
%right '~'
%nonassoc UMINUS
%%

program:
	include
|	program include
|	register
|	program register
|	constant
|	program constant
|	scratch_ram
|	program scratch_ram
|	scb
|	program scb
|	label
|	program label
|	conditional
|	program conditional
|	code
|	program code
;

include:
	T_INCLUDE '<' T_PATH '>'
	{ include_file($3, BRACKETED_INCLUDE); }
|	T_INCLUDE '"' T_PATH '"'
	{ include_file($3, QUOTED_INCLUDE); }
;

register:
	T_REGISTER { cur_symtype = REGISTER; } reg_definition
;

reg_definition:
	T_SYMBOL '{'
		{
			if ($1->type != UNINITIALIZED) {
				stop("Register multiply defined", EX_DATAERR);
				/* NOTREACHED */
			}
			cur_symbol = $1; 
			cur_symbol->type = cur_symtype;
			initialize_symbol(cur_symbol);
		}
		reg_attribute_list
	'}'
		{                    
			/*
			 * Default to allowing everything in for registers
			 * with no bit or mask definitions.
			 */
			if (cur_symbol->info.rinfo->valid_bitmask == 0)
				cur_symbol->info.rinfo->valid_bitmask = 0xFF;

			if (cur_symbol->info.rinfo->size == 0)
				cur_symbol->info.rinfo->size = 1;

			/*
			 * This might be useful for registers too.
			 */
			if (cur_symbol->type != REGISTER) {
				if (cur_symbol->info.rinfo->address == 0)
					cur_symbol->info.rinfo->address =
					    sram_or_scb_offset;
				sram_or_scb_offset +=
				    cur_symbol->info.rinfo->size;
			}
			cur_symbol = NULL;
		}
;

reg_attribute_list:
	reg_attribute
|	reg_attribute_list reg_attribute
;

reg_attribute:		
	reg_address
|	size
|	access_mode
|	bit_defn
|	mask_defn
|	alias
|	accumulator
|	allones
|	allzeros
|	none
|	sindex
;

reg_address:
	T_ADDRESS T_NUMBER
	{
		cur_symbol->info.rinfo->address = $2;
	}
;

size:
	T_SIZE T_NUMBER
	{
		cur_symbol->info.rinfo->size = $2;
	}
;

access_mode:
	T_ACCESS_MODE T_MODE
	{
		cur_symbol->info.rinfo->mode = $2;
	}
;

bit_defn:
	T_BIT T_SYMBOL T_NUMBER
	{
		process_bitmask(BIT, $2, $3);
	}
;

mask_defn:
	T_MASK T_SYMBOL expression
	{
		process_bitmask(MASK, $2, $3.value);
	}
;

alias:
	T_ALIAS	T_SYMBOL
	{
		if ($2->type != UNINITIALIZED) {
			stop("Re-definition of register alias",
			     EX_DATAERR);
			/* NOTREACHED */
		}
		$2->type = ALIAS;
		initialize_symbol($2);
		$2->info.ainfo->parent = cur_symbol;
	}
;

accumulator:
	T_ACCUM
	{
		if (accumulator != NULL) {
			stop("Only one accumulator definition allowed",
			     EX_DATAERR);
			/* NOTREACHED */
		}
		accumulator = cur_symbol;
	}
;

allones:
	T_ALLONES
	{
		if (allones.symbol != NULL) {
			stop("Only one definition of allones allowed",
			     EX_DATAERR);
			/* NOTREACHED */
		}
		allones.symbol = cur_symbol;
	}
;

allzeros:
	T_ALLZEROS
	{
		if (allzeros.symbol != NULL) {
			stop("Only one definition of allzeros allowed",
			     EX_DATAERR);
			/* NOTREACHED */
		}
		allzeros.symbol = cur_symbol;
	}
;

none:
	T_NONE
	{
		if (none.symbol != NULL) {
			stop("Only one definition of none allowed",
			     EX_DATAERR);
			/* NOTREACHED */
		}
		none.symbol = cur_symbol;
	}
;

sindex:
	T_SINDEX
	{
		if (sindex.symbol != NULL) {
			stop("Only one definition of sindex allowed",
			     EX_DATAERR);
			/* NOTREACHED */
		}
		sindex.symbol = cur_symbol;
	}
;

expression:
	expression '|' expression
	{
		 $$.value = $1.value | $3.value;
		 symlist_merge(&$$.referenced_syms,
			       &$1.referenced_syms,
			       &$3.referenced_syms);
	}
|	expression '&' expression
	{
		$$.value = $1.value & $3.value;
		symlist_merge(&$$.referenced_syms,
			       &$1.referenced_syms,
			       &$3.referenced_syms);
	}
|	expression '+' expression
	{
		$$.value = $1.value + $3.value;
		symlist_merge(&$$.referenced_syms,
			       &$1.referenced_syms,
			       &$3.referenced_syms);
	}
|	expression '-' expression
	{
		$$.value = $1.value - $3.value;
		symlist_merge(&($$.referenced_syms),
			       &($1.referenced_syms),
			       &($3.referenced_syms));
	}
|	'(' expression ')'
	{
		$$ = $2;
	}
|	'~' expression
	{
		$$ = $2;
		$$.value = (~$$.value) & 0xFF;
	}
|	'-' expression %prec UMINUS
	{
		$$ = $2;
		$$.value = -$$.value;
	}
|	T_NUMBER
	{
		$$.value = $1;
		SLIST_INIT(&$$.referenced_syms);
	}
|	T_SYMBOL
	{
		symbol_t *symbol;

		symbol = $1;
		switch (symbol->type) {
		case ALIAS:
			symbol = $1->info.ainfo->parent;
		case REGISTER:
		case SCBLOC:
		case SRAMLOC:
			$$.value = symbol->info.rinfo->address;
			break;
		case MASK:
		case BIT:
			$$.value = symbol->info.minfo->mask;
			break;
		case DOWNLOAD_CONST:
		case CONST:
			$$.value = symbol->info.cinfo->value;
			break;
		case UNINITIALIZED:
		default:
		{
			char buf[255];

			snprintf(buf, sizeof(buf),
				 "Undefined symbol %s referenced",
				 symbol->name);
			stop(buf, EX_DATAERR);
			/* NOTREACHED */
			break;
		}
		}
		SLIST_INIT(&$$.referenced_syms);
		symlist_add(&$$.referenced_syms, symbol, SYMLIST_INSERT_HEAD);
	}
;

constant:
	T_CONST T_SYMBOL numerical_value
	{
		if ($2->type != UNINITIALIZED) {
			stop("Re-definition of symbol as a constant",
			     EX_DATAERR);
			/* NOTREACHED */
		}
		$2->type = CONST;
		initialize_symbol($2);
		$2->info.cinfo->value = $3;
		$2->info.cinfo->define = $1;
	}
|	T_CONST T_SYMBOL T_DOWNLOAD
	{
		if ($1) {
			stop("Invalid downloaded constant declaration",
			     EX_DATAERR);
			/* NOTREACHED */
		}
		if ($2->type != UNINITIALIZED) {
			stop("Re-definition of symbol as a downloaded constant",
			     EX_DATAERR);
			/* NOTREACHED */
		}
		$2->type = DOWNLOAD_CONST;
		initialize_symbol($2);
		$2->info.cinfo->value = download_constant_count++;
		$2->info.cinfo->define = FALSE;
	}
;

numerical_value:
	T_NUMBER
	{
		$$ = $1;
	}
|	'-' T_NUMBER
	{
		$$ = -$2;
	}
;

scratch_ram:
	T_SRAM '{'
		{
			cur_symbol = symtable_get(SRAM_SYMNAME);
			cur_symtype = SRAMLOC;
			if (cur_symbol->type != UNINITIALIZED) {
				stop("Only one SRAM definition allowed",
				     EX_DATAERR);
				/* NOTREACHED */
			}
			cur_symbol->type = SRAMLOC;
			initialize_symbol(cur_symbol);
		}
		reg_address
		{
			sram_or_scb_offset = cur_symbol->info.rinfo->address;
		}
		scb_or_sram_reg_list
	'}'
		{
			cur_symbol = NULL;
		}
;

scb:
	T_SCB '{'
		{
			cur_symbol = symtable_get(SCB_SYMNAME);
			cur_symtype = SCBLOC;
			if (cur_symbol->type != UNINITIALIZED) {
				stop("Only one SRAM definition allowed",
				     EX_SOFTWARE);
				/* NOTREACHED */
			}
			cur_symbol->type = SCBLOC;
			initialize_symbol(cur_symbol);
		}
		reg_address
		{
			sram_or_scb_offset = cur_symbol->info.rinfo->address;
		}
		scb_or_sram_reg_list
	'}'
		{
			cur_symbol = NULL;
		}
;

scb_or_sram_reg_list:
	reg_definition
|	scb_or_sram_reg_list reg_definition
;

reg_symbol:
	T_SYMBOL
	{
		process_register(&$1);
		$$.symbol = $1;
		$$.offset = 0;
	}
|	T_SYMBOL '[' T_NUMBER ']'
	{
		process_register(&$1);
		if (($3 + 1) > $1->info.rinfo->size) {
			stop("Accessing offset beyond range of register",
			     EX_DATAERR);
			/* NOTREACHED */
		}
		$$.symbol = $1;
		$$.offset = $3;
	}
|	T_A
	{
		if (accumulator == NULL) {
			stop("No accumulator has been defined", EX_DATAERR);
			/* NOTREACHED */
		}
		$$.symbol = accumulator;
		$$.offset = 0;
	}
;

destination:
	reg_symbol
	{
		test_writable_symbol($1.symbol);
		$$ = $1;
	}
;

immediate:
	expression
	{ $$ = $1; }
;

immediate_or_a:
	expression
	{
		$$ = $1;
	}
|	T_A
	{
		SLIST_INIT(&$$.referenced_syms);
		$$.value = 0;
	}
;

source:
	reg_symbol
	{
		test_readable_symbol($1.symbol);
		$$ = $1;
	}
;

opt_source:
	{
		$$.symbol = NULL;
		$$.offset = 0;
	}
|	',' source
	{ $$ = $2; }
;

ret:
	{ $$ = 0; }
|	T_RET
	{ $$ = 1; }
;

label:
	T_SYMBOL ':'
	{
		if ($1->type != UNINITIALIZED) {
			stop("Program label multiply defined", EX_DATAERR);
			/* NOTREACHED */
		}
		$1->type = LABEL;
		initialize_symbol($1);
		$1->info.linfo->address = instruction_ptr;
	}
;

address:
	T_SYMBOL
	{
		$$.symbol = $1;
		$$.offset = 0;
	}
|	T_SYMBOL '+' T_NUMBER
	{
		$$.symbol = $1;
		$$.offset = $3;
	}
|	T_SYMBOL '-' T_NUMBER
	{
		$$.symbol = $1;
		$$.offset = -$3;
	}
|	'.'
	{
		$$.symbol = NULL;
		$$.offset = 0;
	}
|	'.' '+' T_NUMBER
	{
		$$.symbol = NULL;
		$$.offset = $3;
	}
|	'.' '-' T_NUMBER
	{
		$$.symbol = NULL;
		$$.offset = -$3;
	}
;

conditional:
	T_IF T_CEXPR '{'
	{
		scope_t *new_scope;

		add_conditional($2);
		new_scope = scope_alloc();
		new_scope->type = SCOPE_IF;
		new_scope->begin_addr = instruction_ptr;
		new_scope->func_num = $2->info.condinfo->func_num;
	}
|	T_ELSE T_IF T_CEXPR '{'
	{
		scope_t *new_scope;
		scope_t *scope_context;
		scope_t *last_scope;

		/*
		 * Ensure that the previous scope is either an
		 * if or and else if.
		 */
		scope_context = SLIST_FIRST(&scope_stack);
		last_scope = TAILQ_LAST(&scope_context->inner_scope,
					scope_tailq);
		if (last_scope == NULL
		 || last_scope->type == T_ELSE) {

			stop("'else if' without leading 'if'", EX_DATAERR);
			/* NOTREACHED */
		}
		add_conditional($3);
		new_scope = scope_alloc();
		new_scope->type = SCOPE_ELSE_IF;
		new_scope->begin_addr = instruction_ptr;
		new_scope->func_num = $3->info.condinfo->func_num;
	}
|	T_ELSE '{'