%{
#define BFEHAX

/* macros zum registerzugriff bei kinder */
#define KID_REG(A) bnode->kids[A]->reg
#define KIDKID_REG(A,B) bnode->kids[A]->kids[B]->reg
#define KIDKIDKID_REG(A,B,C) bnode->kids[A]->kids[B]->kids[C]->reg

/* macros zum wertezugriff bei kindern */
#define KID_VAL(A) bnode->kids[A]->val
#define KIDKID_VAL(A,B) bnode->kids[A]->kids[B]->val
#define KIDKIDKID_VAL(A,B,C) bnode->kids[A]->kids[B]->kids[C]->val

#define KID_PARM(A) bnode->kids[A]->param_index
#define KIDKID_PARM(A,B) bnode->kids[A]->kids[B]->param_index
#define KIDKIDKID_PARM(A,B,C) bnode->kids[A]->kids[B]->kids[C]->param_index

/* macros zum zugriff des aktuellen knotens */
#define BN_REG bnode->reg
#define BN_VAL bnode->val

/* wenn sich ein parameter auf der "leseseite" (also links bei at&t syntax)
 * befindet, dann soll dieses register verwendet werden */
#define KIDREG2PARM(A) if(bnode->kids[A]->param_index > -1) { bnode->kids[A]->reg = param_reg(bnode->kids[A]->param_index); }
#define KIDKIDREG2PARM(A,B) if(bnode->kids[A]->kids[B]->param_index > -1) { bnode->kids[A]->kids[B]->reg = param_reg(bnode->kids[A]->kids[B]->param_index); }
#define KIDKIDKIDREG2PARM(A,B,C) if(bnode->kids[A]->kids[B]->kids[C]->param_index > -1) { bnode->kids[A]->kids[B]->kids[C]->reg = param_reg(bnode->kids[A]->kids[B]->kids[C]->param_index); }

/* wenn sich ein parameter auf der "schreibeseite" befindet (also rechts bei
 * at&t syntax), dann muss es vorher in ein temporaeres register gemovt werden */
#define KIDREG2ID(A) if(bnode->kids[A]->op == O_ID && bnode->kids[A]->param_index > -1) move(param_reg(bnode->kids[A]->param_index), bnode->kids[A]->reg);

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

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

void gen_id_eno(struct treenode *bnode)
{
	printf("\t//gen_id_eno\n");
	KIDKIDREG2PARM(1,0);
	KIDKIDREG2PARM(1,1);
	KIDREG2PARM(0);

	printf("\tsub %s,%s,%s\n", BN_REG, KID_REG(0), KIDKID_REG(1,1));
	printf("\tsub %s,%s,%s\n", BN_REG, BN_REG, KIDKID_REG(1,0));
}

void gen_e_imm(struct treenode *bnode, char *instr)
{
	printf("\t//gen_e_imm(%s)\n", instr);
	KIDREG2PARM(0);
	KIDREG2ID(1);
	/* man kann sich ein move der konstante bei der multiplikation ersparen */
	if(strcmp(instr, "mullw") == 0) {
		if(KID_VAL(1) == 1 && strcmp(KID_REG(0), BN_REG) == 0) {
			printf("\t//multiplikation mit 1 wegoptimiert\n");
		} else {
			if(KID_VAL(1) > (65536)-1 || KID_VAL(1) < -65536) {
				moveimm(KID_VAL(1), next_reg(BN_REG,0));
				printf("\tmul %s, %s, %s\n", BN_REG, KID_REG(0), next_reg(BN_REG,0));
			} else {
				printf("\tmul %s, %s, #%d\n", BN_REG, KID_REG(0), KID_VAL(1));
			}
		}
	} else {
		if(strcmp(instr, "sub") == 0 && KID_VAL(1) == 0) {
			printf("\t//subtraktion mit 0 wegoptimiert\n");
			move(KID_REG(0), BN_REG);
		} else {
			if(KID_VAL(1) > (65536)-1 || KID_VAL(1) < -65536) {
				moveimm(KID_VAL(1), next_reg(BN_REG,0));
				printf("\t%s %s, %s, %s\n", instr, BN_REG, KID_REG(0), next_reg(BN_REG,0));
			} else {
				printf("\t%s %s, %s, #%d\n", instr, BN_REG, KID_REG(0), KID_VAL(1));
			}
		}
	}
}

void gen_imm_eno(struct treenode *bnode, char *instr)
{
	printf("\t//gen_imm_eno(%s)\n", instr);
	KIDREG2ID(0);
	KIDREG2PARM(1);
	/* man kann sich ein move der konstante bei der multiplikation ersparen */
	if(strcmp(instr, "mul") == 0) {
		if(KID_VAL(0) == 1 && strcmp(KID_REG(1), BN_REG) == 0) {
			printf("\t//multiplikation mit 1 wegoptimiert\n");
		} else {
			if(KID_VAL(0) > (65536)-1 || KID_VAL(0) < -65536) {
				moveimm(KID_VAL(0), next_reg(BN_REG,0));
				printf("\tmul %s, %s, %s\n", BN_REG, KID_REG(1), next_reg(BN_REG,0));
			} else {
				printf("\tmul %s, %s, #%d\n", BN_REG, KID_REG(1), KID_VAL(0));
			}
		}
	} else { /* addq */
		/* TODO: imm check einbauen */
		printf("\tadd %s, %s, #%d\n", BN_REG, KID_REG(1), KID_VAL(0));
	}
}

void gen_eqless(struct treenode *bnode, char *op, short e0, short e1, short deep)
{
	printf("\t//gen_eqless_%i%i // %i (op: %s)\n", e0, e1, deep, op);
	if(e0) { KIDREG2PARM(0); } else { moveimm(KID_VAL(0), BN_REG); }
	if(e1) { KIDREG2PARM(1); }
	if(strcmp(op,"e")==0 && bnode->kids[1]->op == O_NULL) {
		/* not */
		printf("\tcmp %s, #0\n", KID_REG(0));
		printf("\tmoveq %s, #1\n", BN_REG);
		printf("\tmovne %s, #0\n", BN_REG);
	} else {
		if(!e1) {
			moveimm(KID_VAL(1), KID_REG(1));
		}
		if(strcmp(op, "e")==0) {
			/* eq */
			printf("\tcmp %s,%s\n", KID_REG(0), KID_REG(1));
			printf("\tmoveq %s, #1\n", BN_REG);
			printf("\tmovne %s, #0\n", BN_REG);
		} else if(strcmp(op, "l")==0 || strcmp(op, "g")==0) {
			/* less */
			printf("\tcmp %s, %s\n", KID_REG(1), KID_REG(0));
			printf("\tmovle %s, #0\n", BN_REG);
			printf("\tmovgt %s, #1\n", BN_REG);
		}
	}
}

void gen_subspecial(struct treenode *bnode, short e)
{
	/* tritt z.b. bei snafu_05.0 auf */
	printf("\t//gen_subspecial(%i)\n", e);
	KIDREG2ID(0);
	KIDKIDREG2PARM(1,0);

	/* TODO: Loong// codea_snafu_03.0 */

	if(e) {
		if(KIDKID_VAL(1,0) != 0) {
			printf("\tsubi %s,%s,%d\n", BN_REG, BN_REG, KIDKID_VAL(1,0));
		}
	} else {
		printf("\tsub %s,%s,%s\n", BN_REG, BN_REG, KIDKID_REG(1,0));
	}
	if(e) KIDKIDREG2PARM(1,1);
	printf("\tadd %s,%s,%s\n", BN_REG, BN_REG, KIDKID_REG(1,1));
}

void assign_var(struct treenode *bnode)
{
	printf("\t//assign_var\n");
	KIDREG2PARM(1);
	if (strcmp(bnode->kids[0]->kids[0]->name, bnode->kids[1]->name) != 0) {
		KIDKIDREG2PARM(0,0);
		printf("\tmr %s,%s\n", KID_REG(1), KIDKID_REG(0,0));
	} /*else:  x := x - 1 geht in einem befehl */
	printf("\tsubi %s,%s,%d\n", KID_REG(1), KID_REG(1), KIDKID_VAL(0,1));
}

/* ... dirty */
static short sc[8] = {0};
void make_call(struct treenode *bnode)
{
	int j;
	printf("\t//params pushen\n");
	for(j = 0; j < bnode->soffset; j++) {
		if(sc[j] == 1) {
			printf("\tlwz 20,%d(1)\n", j*4);
			printf("\tstw %s,%d(1)\n", param_reg(j), j*4);
			printf("\tmr %s,20\n", param_reg(j));
		} else if (sc[j] == 0) {
			printf("\tstw %s,%d(1)\n", param_reg(j), j*4);
		}
	}
	printf("\t//vars pushen\n");
	for(j = bnode->soffset; j < bnode->soffset + bnode->vars; j++) {
		printf("\tstw %s,%d(1)\n", param_reg(j), j*4);
	}

	/* TODO: schoener machen... */
	if(strcmp(BN_REG, "14")!=0) {
		printf("\t//tmp register pushen\n");
		printf("\tstw 14,52(1)\n");
		if(strcmp(BN_REG, "15")!=0) {
			printf("\tstw 15,56(1)\n");
			if(strcmp(BN_REG, "16")!=0) {
				printf("\tstw 16,60(1)\n");
			}
		}
	}

	printf("\tbl %s\n", bnode->name);
	move("r0", BN_REG);

	if(strcmp(BN_REG, "14")!=0) {
		printf("\t//tmp register poppen\n");
		if(strcmp(BN_REG, "15")!=0) {
			if(strcmp(BN_REG, "16")!=0) {
				printf("\tlwz 16,60(1)\n");
			}
			printf("\tlwz 15,56(1)\n");
		}
		printf("\tlwz 14,52(1)\n");
	}

	printf("\t//vars poppen\n");
	for(j = bnode->soffset + bnode->vars - 1; j > bnode->soffset - 1; j--) {
		printf("\tlwz %s,%d(1)\n", param_reg(j), j*4);
	}

	printf("\t//params poppen\n");
	for(j = bnode->soffset - 1; j >= 0; j--) {
		if(sc[j] == 0)
			printf("\tlwz %s,%d(1)\n", param_reg(j), j*4);
	}
	for(j = 0; j < bnode->soffset; j++) {
		if(sc[j] > 0)
			printf("\tlwz %s,%d(1)\n", param_reg(j), j*4);
	}

	/* clear stack control array */
	for(j = 0; j < sizeof sc / sizeof sc[0]; j++)
		sc[j] = 0;
}

void prep_arg(struct treenode *bnode, int moveit)
{
	printf("\t//args-nr-> %i (%%%s) [moveit= %i]\n", bnode->soffset, param_reg(bnode->soffset), moveit);
	sc[bnode->soffset] = 1;
	if(moveit) { /* expr */
		if((BN_REG == (char *) NULL) || (bnode->kids[1] != TREENULL && bnode->kids[1]->op == O_ID && bnode->kids[1]->kids[0] == TREENULL && bnode->kids[1]->kids[1] == TREENULL)) {
			if(bnode->kids[1]->name != (char *) NULL && strcmp(bnode->kids[1]->name,"this")!=0) {
				KIDREG2PARM(1);
				printf("\tstw %s,%d(1)\n", KID_REG(1),bnode->soffset*4);
			} else {
				printf("\tstw %s,%d(1)\n", param_reg(bnode->soffset), bnode->soffset*4);
				sc[bnode->soffset] = 2;
			}
		} else {
			printf("\tstw %s,%d(1)\n", BN_REG, bnode->soffset*4);
		}
	} else { /* just O_ID */
		KIDREG2PARM(0);
		printf("\tstw %s,%d(1)\n", KID_REG(0), bnode->soffset*4);
	}
}

void field_lolbfefail(struct treenode *bnode)
{
	printf("\t// field(expr)\n");
	KIDREG2PARM(0);
	printf("\tldr %s, [%s, #%d]\n", BN_REG, KID_REG(0), bnode->soffset * 4);
}

void field_lolbfefail_imm(struct treenode *bnode)
{
	printf("\t// field(imm)\n");
	moveimm(KID_VAL(0), BN_REG);
	printf("\tlwz %s, [%s, #%d]\n", BN_REG, BN_REG, bnode->soffset * 4);
}

%}

%start begin
%term O_RET=1 O_NULL=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 O_FIELD=11 O_MTWO=12 O_MFOUR=13 O_MEIGHT=14 O_MONE=15 O_ASSIGN=16 O_IF=17 O_BOOL=18 O_CALL=19 O_ARG=20 O_NOTHING=21 O_EXPR=22

%%

begin: ret # 0 #
begin: assign # 0 #
begin: ifstat # 0 #
begin: args # 0 #


assign: O_ASSIGN(expr, O_ID) # 1 # KIDREG2PARM(1); printf("\tmr %s,%s\n", KID_REG(1), BN_REG);
assign: O_ASSIGN(imm, O_ID) # 1 # KIDREG2PARM(1); moveimm(KID_VAL(0), KID_REG(1));
assign: O_ASSIGN(O_ID, O_ID) # 1 # KIDREG2PARM(1); KIDREG2PARM(0); printf("\tmr %s,%s\n", KID_REG(1), KID_REG(0));

assign: O_ASSIGN(O_SUB(O_ID,O_NUM), O_ID) # 1 # assign_var(bnode);

assign: O_ASSIGN(expr, O_FIELD(expr)) # 1 # KIDKIDREG2PARM(1,0); printf("\tstw %s,%d(%s)\n", BN_REG, bnode->kids[1]->soffset * 4, KIDKID_REG(1,0));
assign: O_ASSIGN(O_ID, O_FIELD(expr)) # 1 # KIDREG2PARM(0); KIDKIDREG2PARM(1,0); printf("\tstw %s,%d(%s)\n", KID_REG(0), bnode->kids[1]->soffset * 4, KIDKID_REG(1,0));


ifstat: O_IF(O_ID) # 1 # /* fuer faelle wie "if bla then" noetig */ KIDREG2PARM(0); printf("\tcmpwi %s,0\n", KID_REG(0));
ifstat: O_IF(O_BOOL(imm)) # 1 # printf("\tcmpwi %s,0\n", BN_REG);
ifstat: O_IF(expr) # 2 # /* iburg beschummeln :/ */ printf("\tcmpwi %s,0\n", BN_REG);
ifstat: O_IF(O_BOOL(expr)) # 1 # /* dann braucht man kein test */


ret: O_RET(retexpr) # 2 # printf("\t// o_ret(expr)\n"); move(BN_REG, "x0");
ret: O_EXPR(expr) # 0 #

retexpr: O_ID # 1 # printf("\t//*retexpr*/\n"); if(bnode->param_index > -1) move(param_reg(bnode->param_index), BN_REG);
retexpr: expr


expr: O_ID # 0 #
expr: imm # 1 # moveimm(BN_VAL, BN_REG);
expr: O_BOOL(expr) # 0 #

expr: O_CALL(expr) # 0 # make_call(bnode);
expr: O_ARG(expr,expr) # 1 # prep_arg(bnode, 1);
expr: O_ARG(O_ID,expr) # 1 # prep_arg(bnode, 0);
expr: O_NOTHING # 0 #

expr: O_SUB(expr,expr)          # 2 # gen_e_eno(bnode, "sub");
expr: O_SUB(expr,imm)           # 1 # gen_e_imm(bnode, "sub");

expr: O_SUB(expr,O_SUB(O_ID,expr)) # 2 # gen_subspecial(bnode, 0);
expr: O_SUB(expr,O_SUB(imm,expr))  # 2 # gen_subspecial(bnode, 1);

expr: O_SUB(expr, O_ADD(O_ID,expr))    # 1 # gen_id_eno(bnode);


expr: O_ADD(expr,expr)   # 1 # gen_e_eno(bnode, "add");
expr: O_ADD(expr,imm)    # 1 # gen_e_imm(bnode, "add");
expr: O_ADD(imm,expr)    # 1 # gen_imm_eno(bnode, "add");


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


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


expr: O_LESS(expr,expr)          # 3 # gen_eqless(bnode, "l", 1, 1, 0);
expr: O_LESS(expr,imm)           # 3 # gen_eqless(bnode, "l", 1, 0, 0);
expr: O_LESS(imm,expr)           # 3 # gen_eqless(bnode, "g", 0, 1, 0);


expr: O_EQ(expr,expr)          # 3 # gen_eqless(bnode, "e", 1, 1, 0);
expr: O_EQ(expr,imm)           # 3 # gen_eqless(bnode, "e", 1, 0, 0);
expr: O_EQ(imm,expr)           # 3 # gen_eqless(bnode, "e", 0, 1, 0);
expr: O_EQ(expr,O_NULL)        # 3 # gen_eqless(bnode, "e", 1, 0, 0);

expr: O_EQ(O_EQ(expr,O_NULL),O_NULL)  # 3 # gen_eqless(bnode, "ne", 1, 0, 1);
expr: O_EQ(O_EQ(O_EQ(expr,O_NULL),O_NULL),O_NULL) # 3 # gen_eqless(bnode, "e", 1, 0, 2);


expr: O_FIELD(expr) # 1 # field_lolbfefail(bnode);
expr: O_FIELD(imm)  # 1 # field_lolbfefail_imm(bnode);


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_OR(imm,imm)   # 0 # BN_VAL = KID_VAL(0) | KID_VAL(1);
imm: O_NUM # 0 #
imm: O_MONE # 0 #
imm: O_MTWO # 0 #
imm: O_MFOUR # 0 #
imm: O_MEIGHT # 0 #
imm: O_NULL # 0 #

%%

/* vim: filetype=c
 */