%{
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include "symbol_table.h"
	#include "code_gen.h"
	#include "tree.h"
%}

%start		Input
%token		FUNC END STRUCT VAR IF THEN ELSE WHILE DO RETURN OR NOT
%token		ID NUM ASSIGN GREATER

@autoinh symbols stack_offset all_pars
@autosyn node defined_vars immediate

@attributes	{ char *name; } ID
@attributes	{ long value; } NUM
@attributes	{ struct symbol_t *fields; struct symbol_t *symbols; } Program
@attributes	{ struct symbol_t *fields; } Structdef
@attributes	{ struct symbol_t *fields; int offset; } Ids
@attributes	{ struct symbol_t *pars; int num_pars; int all_pars; } Pars
@attributes	{ struct symbol_t *symbols; int defined_vars; } Funcdef 
@attributes	{ struct symbol_t *symbols; int defined_vars; int stack_offset; } Stats
@attributes	{ struct symbol_t *symbols; treenode *node; int immediate; } Expr Term Plusterm Malterm
@attributes	{ struct symbol_t *symbols; treenode *node; } Bool Call Lexpr Field Bterm Orterm Exprs
@attributes	{ struct symbol_t *in_symbols; struct symbol_t *out_symbols; treenode *node; int defined_vars; int stack_offset; } Stat

@traversal @postorder check
@traversal @preorder reg
@traversal @postorder codegen

%%

Input:		  Program
     		@{
		   @i @Program.symbols@ = @Program.fields@;

		   @codegen @revorder(1) printf("\t.text\n");
		@}

		;

Program:	  Funcdef ';' Program
		@{
		   @i @Program.fields@ = @Program.1.fields@;
		@}

		| Structdef ';' Program
		@{
		   @i @Program.fields@ = table_merge(@Structdef.fields@, @Program.1.fields@, 1);
		   @i @Program.1.symbols@ = @Program.0.symbols@;
		@}

		|
		@{ @i @Program.fields@ = new_table(); @}

		;
 
Funcdef:	  FUNC ID '(' Pars ')' Stats END
       		@{
		   @i @Stats.symbols@ = table_merge(@Funcdef.symbols@, @Pars.pars@, 0);
		   @i @Stats.stack_offset@ = 0;
		   @i @Pars.all_pars@ = @Pars.num_pars@;

		   @codegen @revorder(1) function_header(@ID.name@);
		@}

		| FUNC ID '(' ')' Stats END
       		@{
		   @i @Stats.symbols@ = table_merge(@Funcdef.symbols@, new_table(), 0);
		   @i @Stats.stack_offset@ = 0;

		   @codegen @revorder(1) function_header(@ID.name@);
		@}

		;  
 
Structdef: 	  STRUCT Ids END
	 	@{
		   @i @Structdef.fields@ = @Ids.fields@;
		   @i @Ids.offset@ = 0;
		@}

		;  

Ids:		  ID Ids
		@{
		   @i @Ids.fields@ = table_add_symbol(@Ids.1.fields@, @ID.name@, SYMBOL_TYPE_FIELD, 1, @Ids.offset@);
		   @i @Ids.1.offset@ = @Ids.offset@ + 1;
		@}

		|
		@{ @i @Ids.fields@ = new_table(); @}

		;

Pars: 		  Pars ',' ID
		@{
                   @i @Pars.pars@ = table_add_symbol(@Pars.1.pars@, @ID.name@, SYMBOL_TYPE_PARAM, 0, -@Pars.num_pars@);
		   @i @Pars.num_pars@ = @Pars.1.num_pars@ + 1;
                @}

  		| ID
		@{
                   @i @Pars.pars@ = table_add_symbol(new_table(), @ID.name@, SYMBOL_TYPE_PARAM, 0, -1);
                   @i @Pars.num_pars@ = 1;
                @}

		; 
 
Stats:		  Stat ';' Stats
     		@{
		   @i @Stat.in_symbols@ = @Stats.symbols@;
		   @i @Stats.1.symbols@ = @Stat.out_symbols@;
		   @i @Stats.defined_vars@ = @Stat.defined_vars@ + @Stats.1.defined_vars@;
		   @i @Stats.1.stack_offset@ = @Stats.stack_offset@ + @Stat.defined_vars@ * 8;

		   @codegen /* write_tree(@Stat.node@, 0); */ burm_label(@Stat.node@); burm_reduce(@Stat.node@, 1);
		@}

		|
		@{ @i @Stats.defined_vars@ = 0; @}

		;  
 
Stat:		  VAR ID ASSIGN Expr
    		@{
		   @i @Stat.out_symbols@ = table_add_symbol(clone_table(@Stat.in_symbols@), @ID.name@, SYMBOL_TYPE_VAR, 0, 0);
		   @i @Expr.symbols@ = @Stat.in_symbols@;
		   @i @Stat.node@ = (treenode *)NULL;
		   @i @Stat.defined_vars@ = 1;
		@}

		| Lexpr ASSIGN Expr
		@{
		   @i @Stat.out_symbols@ = @Stat.in_symbols@;
		   @i @Lexpr.symbols@ = @Stat.in_symbols@;
		   @i @Expr.symbols@ = @Stat.in_symbols@;
		   @i @Stat.node@ = (treenode *)NULL;
		   @i @Stat.defined_vars@ = 0;
		@}

		| IF Bool THEN Stats END
		@{
		   @i @Bool.symbols@ = @Stat.in_symbols@;
		   @i @Stats.symbols@ = @Stat.in_symbols@;
		   @i @Stat.out_symbols@ = @Stat.in_symbols@;
		   @i @Stat.node@ = (treenode *)NULL;
		@}

		| IF Bool THEN Stats ELSE Stats END
		@{
		   @i @Bool.symbols@ = @Stat.in_symbols@;
		   @i @Stats.symbols@ = @Stat.in_symbols@;
		   @i @Stats.1.symbols@ = @Stat.in_symbols@;
		   @i @Stat.out_symbols@ = @Stat.in_symbols@;
		   @i @Stat.node@ = (treenode *)NULL;
		   @i @Stat.defined_vars@ = @Stats.defined_vars@ + @Stats.1.defined_vars@;
		@}

		| WHILE Bool DO Stats END
		@{
		   @i @Bool.symbols@ = @Stat.in_symbols@;
		   @i @Stats.symbols@ = @Stat.in_symbols@;
		   @i @Stat.out_symbols@ = @Stat.in_symbols@;
		   @i @Stat.node@ = (treenode *)NULL;
		@}

		| Call
		@{
		   @i @Call.symbols@ = @Stat.in_symbols@;
		   @i @Stat.out_symbols@ = @Stat.in_symbols@;
		   @i @Stat.node@ = (treenode *)NULL;
		   @i @Stat.defined_vars@ = 0;
		@}

		| RETURN Expr
		@{
		   @i @Expr.symbols@ = @Stat.in_symbols@;
		   @i @Stat.out_symbols@ = @Stat.in_symbols@;
		   @i @Stat.node@ = new_node(OP_Return, @Expr.node@, (treenode *)NULL);

		   @reg @Stat.node@->reg = get_next_reg((char *)NULL, 0); @Expr.node@->reg = @Stat.node@->reg;
		   @i @Stat.defined_vars@ = 0;
		@}

		;
 
Lexpr:		  ID
		@{
		   @i @Lexpr.node@ = (treenode *)NULL;
		   @check check_variable(@Lexpr.symbols@, @ID.name@);
		@}

		| Field
		;
 
Expr: 		  '-' Term
		@{
		   @i @Expr.node@ = new_node(OP_Negation, @Term.node@, (treenode *)NULL);

		   @reg @Term.node@->reg = @Expr.node@->reg;
		@}

    		| Term
		@{ @reg @Term.node@->reg = @Expr.node@->reg; @}

		| Term Plusterm
		@{
		   @i @Expr.node@ = new_node(OP_Addition, @Term.node@, @Plusterm.node@);
		   @i @Expr.immediate@ = @Term.immediate@ && @Plusterm.immediate@;

		   @reg if(!@Plusterm.immediate@) { @Plusterm.node@->reg = @Expr.node@->reg; @Term.node@->reg = (@Term.node@->op==OP_ID && table_lookup(@Term.symbols@, @Term.node@->name)->type==SYMBOL_TYPE_PARAM) ? get_param_reg(-table_lookup(@Term.symbols@, @Term.node@->name)->stack_offset) : get_next_reg(@Plusterm.node@->reg, @Expr.node@->skip_reg); @Plusterm.node@->skip_reg = 1; } else { @Term.node@->reg = @Expr.node@->reg; @Plusterm.node@->reg = get_next_reg(@Term.node@->reg, @Expr.node@->skip_reg); }
		@}

		| Term Malterm
		@{
		   @i @Expr.node@ = new_node(OP_Multiplication, @Term.node@, @Malterm.node@);
		   @i @Expr.immediate@ = @Term.immediate@ && @Malterm.immediate@;

		   @reg if(!@Malterm.immediate@) { @Malterm.node@->reg = @Expr.node@->reg; @Term.node@->reg = (@Term.node@->op==OP_ID && table_lookup(@Term.symbols@, @Term.node@->name)->type==SYMBOL_TYPE_PARAM) ? get_param_reg(-table_lookup(@Term.symbols@, @Term.node@->name)->stack_offset) : get_next_reg(@Malterm.node@->reg, @Expr.node@->skip_reg); @Malterm.node@->skip_reg = 1; } else { @Term.node@-> reg = @Expr.node@->reg; @Malterm.node@->reg = get_next_reg(@Term.node@->reg, @Expr.node@->skip_reg); }
		@}

		;

Plusterm:	  '+' Term Plusterm
		@{
		   @i @Plusterm.node@ = new_node(OP_Addition, @Term.node@, @Plusterm.1.node@);
		   @i @Plusterm.immediate@ = @Term.immediate@ && @Plusterm.1.immediate@;

		   @reg @Plusterm.1.node@->reg = @Plusterm.node@->reg; @Term.node@->reg = (@Term.node@->op==OP_ID && table_lookup(@Term.symbols@, @Term.node@->name)->type==SYMBOL_TYPE_PARAM) ? get_param_reg(-table_lookup(@Term.symbols@, @Term.node@->name)->stack_offset) : get_next_reg(@Plusterm.1.node@->reg, @Plusterm.node@->skip_reg); 
		@}

		| '+' Term
		@{ @reg @Term.node@->reg = @Plusterm.node@->reg; @}

		;

Malterm:	  '*' Term Malterm
		@{
		   @i @Malterm.node@ = new_node(OP_Multiplication, @Term.node@, @Malterm.1.node@);
		   @i @Malterm.immediate@ = @Term.immediate@ && @Malterm.1.immediate@;

		   @reg @Malterm.1.node@->reg = @Malterm.node@->reg; @Term.node@->reg = (@Term.node@->op==OP_ID && table_lookup(@Term.symbols@, @Term.node@->name)->type==SYMBOL_TYPE_PARAM) ? get_param_reg(-table_lookup(@Term.symbols@, @Term.node@->name)->stack_offset) : get_next_reg(@Malterm.1.node@->reg, @Malterm.node@->skip_reg); 
		@}

       		| '*' Term
		@{ @reg @Term.node@->reg = @Malterm.node@->reg; @}

		;
 
Term:		  '(' Expr ')'
		@{ @reg @Expr.node@->reg = @Term.node@->reg; @}

    		| ID
		@{
		   @i @Term.node@ = new_named_leaf_value(OP_ID, @ID.name@, (table_lookup(@Term.symbols@, @ID.name@)==NULL) ? 0 : table_lookup(@Term.symbols@, @ID.name@)->stack_offset);
		   @i @Term.immediate@ = 0;

		   @check check_variable(@Term.symbols@, @ID.name@);
		@}

		| NUM
		@{
		   @i @Term.node@ = new_number_leaf(@NUM.value@);
		   @i @Term.immediate@ = 1;
		@}

		| Call
		@{ @i @Term.immediate@ = 0; @}

		| Field
		@{
		   @i @Term.immediate@ = 0;

		   @reg @Field.node@->reg = @Term.node@->reg;
		@}

		;

Bool:		  Bterm
		| Bterm Orterm
		@{ @i @Bool.node@ = new_node(OP_Disjunction, @Bterm.node@, @Orterm.node@); @}

		| NOT Bterm
		@{ @i @Bool.node@ = new_node(OP_Not, @Bterm.node@, (treenode *)NULL); @}

		;

Orterm:		  OR Bterm Orterm
      		@{ @i @Orterm.node@ = new_node(OP_Disjunction, @Bterm.node@, @Orterm.1.node@); @}

      		| OR Bterm
		;

Bterm:		  Term GREATER Term
		@{ @i @Bterm.node@ = new_node(OP_Greater, @Term.node@, @Term.1.node@); @}

     		| Term '=' Term
		@{ @i @Bterm.node@ = new_node(OP_Equal, @Term.node@, @Term.1.node@); @}

		| '(' Bool ')'
		;

Field:		  Term '.' ID
		@{
		   @i @Field.node@ = new_node_value(OP_Field, @Term.node@, new_named_leaf(OP_ID, @ID.name@), table_lookup(@Field.symbols@, @ID.name@)==(struct symbol_t *)NULL ? 0 : table_lookup(@Field.symbols@, @ID.name@)->stack_offset);

		   @check check_field(@Field.symbols@, @ID.name@);

		   @reg @Term.node@->reg = @Field.node@->reg; @Field.node@->kids[1]->reg = get_next_reg(@Field.node@->reg, 0); 
		@}

     		;

Call:		  ID '(' Exprs ')'
		@{ @i @Call.node@ = new_node(OP_Call, new_named_leaf(OP_ID, @ID.name@), @Exprs.node@); @}

		| ID '(' ')'
		@{ @i @Call.node@ = new_node(OP_Call, new_named_leaf(OP_ID, @ID.name@), NULL); @}

    		;

Exprs:		  Expr
		| Exprs ',' Expr
		@{ @i @Exprs.node@ = new_node(OP_Exprs, @Exprs.1.node@, @Expr.node@); @}

		;

%%

extern int yylex();
extern int yylineno;

int yyerror(char *error_text) {
	fprintf(stderr,"Line %i: %s\n",yylineno, error_text);
	exit(2);
}

int main(int argc, char **argv) {
	yyparse();
	return 0;
}