%{
#define BFEHAX

#define KID_REG(A) bnode->kids[A]->reg
#define KID_VAL(A) bnode->kids[A]->val
#define BN_REG bnode->reg
#define BN_VAL bnode->val

/* falls ein parameter auf der "leseseite" ist, soll das statt ein weiteres
 * register verwendet werden */
#define KIDREG2PARM(A) if(bnode->kids[A]->param_index > -1) { bnode->kids[A]->reg = param_reg(bnode->kids[A]->param_index); }

#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include "tree.h"
#include "chelper.h"

void gen_e_eno(struct treenode *bnode, char *instr)
{
	KIDREG2PARM(1);
	printf("\t%s %%%s, %%%s\n", instr, KID_REG(1), KID_REG(0));
}

void gen_e_imm(struct treenode *bnode, char *instr)
{
	/* man kann sich ein move der konstante bei der multiplikation ersparen */
	if(strcmp(instr, "imulq") == 0) {
		printf("\timulq $%li, %%%s, %%%s\n", KID_VAL(1), KID_REG(0), BN_REG);
	} else {
		printf("\t%s $%li, %%%s\n", instr, KID_VAL(1), KID_REG(0));
		move(KID_REG(0), BN_REG);
	}
}

void gen_imm_eno(struct treenode *bnode, char *instr)
{
	KIDREG2PARM(1);
	/* man kann sich ein move der konstante bei der multiplikation ersparen */
	if(strcmp(instr, "imulq") == 0) {
		printf("\timulq $%li, %%%s, %%%s\n", KID_VAL(0), KID_REG(1), BN_REG);
	} else {
		moveimm(KID_VAL(0), BN_REG);
		printf("\t%s %%%s, %%%s\n", instr, KID_REG(1), BN_REG);
	}
}

void gen_eqless_footer(struct treenode *bnode, char *op)
{
	moveimm(1, BN_REG);
	printf("\tcmov%s %%%2$s, %%%2$s\n", op, BN_REG);
	moveimm(0, KID_REG(1));
	printf("\tcmovn%s %%%s, %%%s\n", op, KID_REG(1), BN_REG);
}

void gen_eqless_ee(struct treenode *bnode, char *op)
{
	printf("\t//gen_eqless_ee\n");
	KIDREG2PARM(0);
#if 0
	/* TODO */
	KIDREG2PARM(1)
#endif
	printf("\tcmp %%%s, %%%s\n", KID_REG(1), KID_REG(0));

	gen_eqless_footer(bnode, op);
}

void gen_eqless_ei(struct treenode *bnode, char *op)
{
	printf("\t//gen_eqless_ei\n");
	KIDREG2PARM(0);
#if 0
	/* TODO */
	KIDREG2PARM(1)
#endif
	printf("\tcmp $%li, %%%s\n", KID_VAL(1), KID_REG(0));

	gen_eqless_footer(bnode, op);
}

void gen_eqless_ie(struct treenode *bnode, char *op)
{
	printf("\t//gen_eqless_ie\n");
	moveimm(KID_VAL(0), BN_REG);
	printf("\tcmp %%%s, %%%s\n", KID_REG(1), BN_REG);

	gen_eqless_footer(bnode, op);
}

%}

%start begin
%term O_RET=1 O_NOT=2 O_SUB=3 O_MUL=4 O_OR=5 O_LESS=6 O_EQ=7 O_ID=8 O_ADD=9 O_NUM=10

%%

begin: ret # 0 # printf("\n");
ret: O_RET(expr) # 2 # move(BN_REG, "rax"); func_footer();

expr: O_ID # 1 # if(bnode->param_index > -1) move(param_reg(bnode->param_index), BN_REG);
expr: imm # 1 # moveimm(BN_VAL, BN_REG);

expr: O_SUB(expr,exprno) # 1 # gen_e_eno(bnode, "subq");
expr: O_SUB(expr,imm) # 2 # gen_e_imm(bnode, "subq");
expr: O_SUB(imm,exprno) # 2 # gen_imm_eno(bnode, "subq");

expr: O_ADD(expr,exprno) # 1 # gen_e_eno(bnode, "addq");
expr: O_ADD(imm,expr) # 2 # gen_e_imm(bnode, "addq");

expr: O_MUL(expr,exprno) # 1 # gen_e_eno(bnode, "imulq");
expr: O_MUL(expr,imm) # 1 # gen_e_imm(bnode, "imulq");
expr: O_MUL(imm,exprno) # 1 # gen_imm_eno(bnode, "imulq");

expr: O_OR(expr,exprno) # 1 # gen_e_eno(bnode, "orq");
expr: O_OR(expr,imm) # 2 # gen_e_imm(bnode, "orq");

expr: O_LESS(expr,expr) # 5 # gen_eqless_ee(bnode, "l");
expr: O_LESS(expr,imm) # 5 # gen_eqless_ei(bnode, "l");
expr: O_LESS(imm,expr) # 6 # gen_eqless_ie(bnode, "l");

expr: O_EQ(expr,expr) # 5 # gen_eqless_ee(bnode, "e");
expr: O_EQ(expr,imm) # 5 # gen_eqless_ei(bnode, "e");
expr: O_EQ(imm,expr) # 6 # gen_eqless_ie(bnode, "e");


exprno: O_ID # 0 # /* brauchen wir nicht 'zwischenlagern', weil nur gelesen wird */
exprno: expr


imm: O_ADD(imm,imm)  # 0 # BN_VAL = KID_VAL(0) + KID_VAL(1);
imm: O_SUB(imm,imm)  # 0 # BN_VAL = KID_VAL(0) - KID_VAL(1);
imm: O_MUL(imm,imm)  # 0 # BN_VAL = KID_VAL(0) * KID_VAL(1);
imm: O_LESS(imm,imm) # 0 # BN_VAL = KID_VAL(0) < KID_VAL(1) ? 1 : 0;
imm: O_EQ(imm,imm)   # 0 # BN_VAL = KID_VAL(0) = KID_VAL(1) ? 1 : 0;
imm: O_NUM # 0 #

%%

/* vim: filetype=c
 */