decoder.h

DOSBox emulates a full x86 pc with sound and dos. Its main use is to run old dosgames on platforms w

		gen_releasereg(DREG(TMPW));
	} else {
		if (op<=DOP_TEST) {
			if (op==DOP_ADC || op==DOP_SBB) gen_needcarry();
			else gen_discardflags();
		}
		gen_dop_word(op,decode.big_op,rm_reg,&DynRegs[decode.modrm.rm]);
	}
}

static void dyn_mov_evgv(void) {
	dyn_get_modrm();
	DynReg * rm_reg=&DynRegs[decode.modrm.reg];
	if (decode.modrm.mod<3) {
		dyn_fill_ea();
		dyn_write_word_release(DREG(EA),rm_reg,decode.big_op);
	} else {
		gen_dop_word(DOP_MOV,decode.big_op,&DynRegs[decode.modrm.rm],rm_reg);
	}
}

static void dyn_mov_gvev(void) {
	dyn_get_modrm();
	DynReg * rm_reg=&DynRegs[decode.modrm.reg];
	if (decode.modrm.mod<3) {
		dyn_fill_ea();
		dyn_read_word_release(DREG(EA),rm_reg,decode.big_op);
	} else {
		gen_dop_word(DOP_MOV,decode.big_op,rm_reg,&DynRegs[decode.modrm.rm]);
	}
}
static void dyn_mov_eviv(void) {
	dyn_get_modrm();
	if (decode.modrm.mod<3) {
		dyn_fill_ea();
		gen_call_write(DREG(EA),decode.big_op ? decode_fetchd() : decode_fetchw(),decode.big_op?4:2);
		dyn_check_bool_exception_al();
	} else {
		gen_dop_word_imm(DOP_MOV,decode.big_op,&DynRegs[decode.modrm.rm],decode.big_op ? decode_fetchd() : decode_fetchw());
	}
}

static void dyn_mov_ev_gb(bool sign) {
	dyn_get_modrm();DynReg * rm_reg=&DynRegs[decode.modrm.reg];
	if (decode.modrm.mod<3) {
		dyn_fill_ea();
		dyn_read_byte_release(DREG(EA),DREG(TMPB),false);
		gen_extend_byte(sign,decode.big_op,rm_reg,DREG(TMPB),0);
		gen_releasereg(DREG(TMPB));
	} else {
		gen_extend_byte(sign,decode.big_op,rm_reg,&DynRegs[decode.modrm.rm&3],decode.modrm.rm&4);
	}
}

static void dyn_mov_ev_gw(bool sign) {
	if (!decode.big_op) {
		dyn_mov_gvev();
		return;
	}
	dyn_get_modrm();DynReg * rm_reg=&DynRegs[decode.modrm.reg];
	if (decode.modrm.mod<3) {
		dyn_fill_ea();
		dyn_read_word_release(DREG(EA),DREG(TMPW),false);
		gen_extend_word(sign,rm_reg,DREG(TMPW));
		gen_releasereg(DREG(TMPW));
	} else {
		gen_extend_word(sign,rm_reg,&DynRegs[decode.modrm.rm]);
	}
}

static void dyn_dshift_ev_gv(bool left,bool immediate) {
	dyn_get_modrm();
	DynReg * rm_reg=&DynRegs[decode.modrm.reg];
	DynReg * ea_reg;
	if (decode.modrm.mod<3) {
		dyn_fill_ea();ea_reg=DREG(TMPW);
		dyn_read_word(DREG(EA),DREG(TMPW),decode.big_op);
	} else ea_reg=&DynRegs[decode.modrm.rm];
	gen_needflags();
	if (immediate) gen_dshift_imm(decode.big_op,left,ea_reg,rm_reg,decode_fetchb());
	else gen_dshift_cl(decode.big_op,left,ea_reg,rm_reg,DREG(ECX));
	if (decode.modrm.mod<3) {
		dyn_write_word_release(DREG(EA),DREG(TMPW),decode.big_op);
		gen_releasereg(DREG(TMPW));
	}
}


static DualOps grp1_table[8]={DOP_ADD,DOP_OR,DOP_ADC,DOP_SBB,DOP_AND,DOP_SUB,DOP_XOR,DOP_CMP};
static void dyn_grp1_eb_ib(void) {
	dyn_get_modrm();
	DualOps op=grp1_table[decode.modrm.reg];
	if (decode.modrm.mod<3) {
		dyn_fill_ea();
		if ((op<=DOP_TEST) && (op!=DOP_ADC && op!=DOP_SBB)) set_skipflags(true);
		dyn_read_byte(DREG(EA),DREG(TMPB),false);
		if (op<=DOP_TEST) {
			if (op==DOP_ADC || op==DOP_SBB) gen_needcarry();
			else set_skipflags(false);
		}
		gen_dop_byte_imm(op,DREG(TMPB),0,decode_fetchb());
		if (op!=DOP_CMP) dyn_write_byte_release(DREG(EA),DREG(TMPB),false);
		else gen_releasereg(DREG(EA));
		gen_releasereg(DREG(TMPB));
	} else {
		if (op<=DOP_TEST) {
			if (op==DOP_ADC || op==DOP_SBB) gen_needcarry();
			else gen_discardflags();
		}
		dyn_dop_byte_imm(op,&DynRegs[decode.modrm.rm&3],decode.modrm.rm&4);
	}
}

static void dyn_grp1_ev_ivx(bool withbyte) {
	dyn_get_modrm();
	DualOps op=grp1_table[decode.modrm.reg];
	if (decode.modrm.mod<3) {
		dyn_fill_ea();
		if ((op<=DOP_TEST) && (op!=DOP_ADC && op!=DOP_SBB)) set_skipflags(true);
		dyn_read_word(DREG(EA),DREG(TMPW),decode.big_op);
		if (op<=DOP_TEST) {
			if (op==DOP_ADC || op==DOP_SBB) gen_needcarry();
			else set_skipflags(false);
		}
		if (!withbyte) {
			dyn_dop_word_imm(op,decode.big_op,DREG(TMPW));
		} else {
			gen_dop_word_imm(op,decode.big_op,DREG(TMPW),(Bit8s)decode_fetchb());
		}
		if (op!=DOP_CMP) dyn_write_word_release(DREG(EA),DREG(TMPW),decode.big_op);
		else gen_releasereg(DREG(EA));
		gen_releasereg(DREG(TMPW));
	} else {
		if (op<=DOP_TEST) {
			if (op==DOP_ADC || op==DOP_SBB) gen_needcarry();
			else gen_discardflags();
		}
		if (!withbyte) {
			dyn_dop_word_imm(op,decode.big_op,&DynRegs[decode.modrm.rm]);
		} else {
			gen_dop_word_imm(op,decode.big_op,&DynRegs[decode.modrm.rm],(Bit8s)decode_fetchb());
		}
	}
}

enum grp2_types {
	grp2_1,grp2_imm,grp2_cl,
};

static void dyn_grp2_eb(grp2_types type) {
	dyn_get_modrm();DynReg * src;Bit8u src_i;
	if (decode.modrm.mod<3) {
		dyn_fill_ea();dyn_read_byte(DREG(EA),DREG(TMPB),false);
		src=DREG(TMPB);
		src_i=0;
	} else {
		src=&DynRegs[decode.modrm.rm&3];
		src_i=decode.modrm.rm&4;
	}
	switch (type) {
	case grp2_1:
		/* rotates (first 4 ops) alter cf/of only; shifts (last 4 ops) alter all flags */
		if (decode.modrm.reg < 4) gen_needflags();
		else gen_discardflags();
		gen_shift_byte_imm(decode.modrm.reg,src,src_i,1);
		break;
	case grp2_imm: {
		Bit8u imm=decode_fetchb();
		if (imm) {
			/* rotates (first 4 ops) alter cf/of only; shifts (last 4 ops) alter all flags */
			if (decode.modrm.reg < 4) gen_needflags();
			else gen_discardflags();
			gen_shift_byte_imm(decode.modrm.reg,src,src_i,imm);
		} else return;
		}
		break;
	case grp2_cl:
		gen_needflags();	/* flags must not be changed on ecx==0 */
		gen_shift_byte_cl (decode.modrm.reg,src,src_i,DREG(ECX));
		break;
	}
	if (decode.modrm.mod<3) {
		dyn_write_byte_release(DREG(EA),src,false);
		gen_releasereg(src);
	}
}

static void dyn_grp2_ev(grp2_types type) {
	dyn_get_modrm();DynReg * src;
	if (decode.modrm.mod<3) {
		dyn_fill_ea();dyn_read_word(DREG(EA),DREG(TMPW),decode.big_op);
		src=DREG(TMPW);
	} else {
		src=&DynRegs[decode.modrm.rm];
	}
	switch (type) {
	case grp2_1:
		/* rotates (first 4 ops) alter cf/of only; shifts (last 4 ops) alter all flags */
		if (decode.modrm.reg < 4) gen_needflags();
		else gen_discardflags();
		gen_shift_word_imm(decode.modrm.reg,decode.big_op,src,1);
		break;
	case grp2_imm: {
		Bitu val;
		if (decode_fetchb_imm(val)) {
			if (decode.modrm.reg < 4) gen_needflags();
			else gen_discardflags();
			gen_load_host((void*)val,DREG(TMPB),1);
			gen_shift_word_cl(decode.modrm.reg,decode.big_op,src,DREG(TMPB));
			gen_releasereg(DREG(TMPB));
			break;
		}
		Bit8u imm=(Bit8u)val;
		if (imm) {
			/* rotates (first 4 ops) alter cf/of only; shifts (last 4 ops) alter all flags */
			if (decode.modrm.reg < 4) gen_needflags();
			else gen_discardflags();
			gen_shift_word_imm(decode.modrm.reg,decode.big_op,src,imm);
		} else return;
		}
		break;
	case grp2_cl:
		gen_needflags();	/* flags must not be changed on ecx==0 */
		gen_shift_word_cl (decode.modrm.reg,decode.big_op,src,DREG(ECX));
		break;
	}
	if (decode.modrm.mod<3) {
		dyn_write_word_release(DREG(EA),src,decode.big_op);
		gen_releasereg(src);
	}
}

static void dyn_grp3_eb(void) {
	dyn_get_modrm();DynReg * src;Bit8u src_i;
	if (decode.modrm.mod<3) {
		dyn_fill_ea();
		if ((decode.modrm.reg==0) || (decode.modrm.reg==3)) set_skipflags(true);
		dyn_read_byte(DREG(EA),DREG(TMPB),false);
		src=DREG(TMPB);src_i=0;
	} else {
		src=&DynRegs[decode.modrm.rm&3];
		src_i=decode.modrm.rm&4;
	}
	switch (decode.modrm.reg) {
	case 0x0:	/* test eb,ib */
		set_skipflags(false);gen_dop_byte_imm(DOP_TEST,src,src_i,decode_fetchb());
		goto skipsave;
	case 0x2:	/* NOT Eb */
		gen_sop_byte(SOP_NOT,src,src_i);
		break;
	case 0x3:	/* NEG Eb */
		set_skipflags(false);gen_sop_byte(SOP_NEG,src,src_i);
		break;
	case 0x4:	/* mul Eb */
		gen_needflags();gen_mul_byte(false,DREG(EAX),src,src_i);
		goto skipsave;
	case 0x5:	/* imul Eb */
		gen_needflags();gen_mul_byte(true,DREG(EAX),src,src_i);
		goto skipsave;
	case 0x6:	/* div Eb */
	case 0x7:	/* idiv Eb */
		/* EAX could be used, so precache it */
		if (decode.modrm.mod==3)
			gen_dop_byte(DOP_MOV,DREG(TMPB),0,&DynRegs[decode.modrm.rm&3],decode.modrm.rm&4);
		gen_releasereg(DREG(EAX));
		gen_call_function((decode.modrm.reg==6) ? (void *)&dyn_helper_divb : (void *)&dyn_helper_idivb,
			"%Rd%Dd",DREG(TMPB),DREG(TMPB));
		dyn_check_bool_exception(DREG(TMPB));
		goto skipsave;
	}
	/* Save the result if memory op */
	if (decode.modrm.mod<3) dyn_write_byte_release(DREG(EA),src,false);
skipsave:
	gen_releasereg(DREG(TMPB));gen_releasereg(DREG(EA));
}

static void dyn_grp3_ev(void) {
	dyn_get_modrm();DynReg * src;
	if (decode.modrm.mod<3) {
		dyn_fill_ea();src=DREG(TMPW);
		if ((decode.modrm.reg==0) || (decode.modrm.reg==3)) set_skipflags(true);
		dyn_read_word(DREG(EA),DREG(TMPW),decode.big_op);
	} else src=&DynRegs[decode.modrm.rm];
	switch (decode.modrm.reg) {
	case 0x0:	/* test ev,iv */
		set_skipflags(false);gen_dop_word_imm(DOP_TEST,decode.big_op,src,decode.big_op ? decode_fetchd() : decode_fetchw());
		goto skipsave;
	case 0x2:	/* NOT Ev */
		gen_sop_word(SOP_NOT,decode.big_op,src);
		break;
	case 0x3:	/* NEG Eb */
		set_skipflags(false);gen_sop_word(SOP_NEG,decode.big_op,src);
		break;
	case 0x4:	/* mul Eb */
		gen_needflags();gen_mul_word(false,DREG(EAX),DREG(EDX),decode.big_op,src);
		goto skipsave;
	case 0x5:	/* imul Eb */
		gen_needflags();gen_mul_word(true,DREG(EAX),DREG(EDX),decode.big_op,src);
		goto skipsave;
	case 0x6:	/* div Eb */
	case 0x7:	/* idiv Eb */
		/* EAX could be used, so precache it */
		if (decode.modrm.mod==3)
			gen_dop_word(DOP_MOV,decode.big_op,DREG(TMPW),&DynRegs[decode.modrm.rm]);
		gen_releasereg(DREG(EAX));gen_releasereg(DREG(EDX));
		void * func=(decode.modrm.reg==6) ?
			(decode.big_op ? (void *)&dyn_helper_divd : (void *)&dyn_helper_divw) :
			(decode.big_op ? (void *)&dyn_helper_idivd : (void *)&dyn_helper_idivw);
		gen_call_function(func,"%Rd%Dd",DREG(TMPB),DREG(TMPW));
		dyn_check_bool_exception(DREG(TMPB));
		gen_releasereg(DREG(TMPB));
		goto skipsave;
	}
	/* Save the result if memory op */
	if (decode.modrm.mod<3) dyn_write_word_release(DREG(EA),src,decode.big_op);
skipsave:
	gen_releasereg(DREG(TMPW));gen_releasereg(DREG(EA));
}

static void dyn_mov_ev_seg(void) {
	dyn_get_modrm();
	gen_load_host(&Segs.val[decode.modrm.reg],DREG(TMPW),2);
	if (decode.modrm.mod<3) {
		dyn_fill_ea();
		dyn_write_word_release(DREG(EA),DREG(TMPW),false);
	} else {
		gen_dop_word(DOP_MOV,decode.big_op,&DynRegs[decode.modrm.rm],DREG(TMPW));
	}
	gen_releasereg(DREG(TMPW));
}

static void dyn_load_seg(SegNames seg,DynReg * src) {
	if (cpu.pmode) {
		gen_call_function((void *)&CPU_SetSegGeneral,"%Rd%Id%Drw",DREG(TMPB),seg,src);
		dyn_check_bool_exception(DREG(TMPB));
		gen_releasereg(DREG(TMPB));
	} else gen_call_function((void *)CPU_SetSegGeneral,"%Id%Drw",seg,src);
	gen_releasereg(&DynRegs[G_ES+seg]);
}

static void dyn_load_seg_off_ea(SegNames seg) {
	dyn_get_modrm();
	if (GCC_UNLIKELY(decode.modrm.mod<3)) {
		dyn_fill_ea();
		gen_lea(DREG(TMPB),DREG(EA),0,0,decode.big_op ? 4:2);
		dyn_read_word(DREG(TMPB),DREG(TMPB),false);
		dyn_read_word_release(DREG(EA),DREG(TMPW),decode.big_op);
		dyn_load_seg(seg,DREG(TMPB));gen_releasereg(DREG(TMPB));
		gen_dop_word(DOP_MOV,decode.big_op,&DynRegs[decode.modrm.reg],DREG(TMPW));
	} else {
		IllegalOption("dyn_load_seg_off_ea");
	}
}

static void dyn_mov_seg_ev(void) {
	dyn_get_modrm();
	SegNames seg=(SegNames)decode.modrm.reg;
	if (GCC_UNLIKELY(seg==cs)) IllegalOption("dyn_mov_seg_ev");
	if (decode.modrm.mod<3) {
		dyn_fill_ea();
		dyn_read_word(DREG(EA),DREG(EA),false);
		dyn_load_seg(seg,DREG(EA));
		gen_releasereg(DREG(EA));
	} else {
		dyn_load_seg(seg,&DynRegs[decode.modrm.rm]);
	}
}

static void dyn_push_seg(SegNames seg) {
	gen_load_host(&Segs.val[seg],DREG(TMPW),2);
	dyn_push(DREG(TMPW));
	gen_releasereg(DREG(TMPW));
}

static void dyn_pop_seg(SegNames seg) {
	if (!cpu.pmode) {
		dyn_pop(DREG(TMPW));
		dyn_load_seg(seg,DREG(TMPW));
		gen_releasereg(DREG(TMPW));
	} else {
		gen_releasereg(DREG(ESP));
		gen_call_function((void *)&CPU_PopSeg,"%Rd%Id%Id",DREG(TMPB),seg,decode.big_op);
		dyn_check_bool_exception(DREG(TMPB));
		gen_releasereg(DREG(TMPB));
		gen_releasereg(&DynRegs[G_ES+seg]);
		gen_releasereg(DREG(ESP));
	}
}

static void dyn_pop_ev(void) {
	dyn_pop(DREG(TMPW));
	dyn_get_modrm();
	if (decode.modrm.mod<3) {
		dyn_fill_ea();
//		dyn_write_word_release(DREG(EA),DREG(TMPW),decode.big_op);
		if (decode.big_op) gen_call_function((void *)&mem_writed_dyncorex86,"%Ddr%Dd",DREG(EA),DREG(TMPW));
		else gen_call_function((void *)&mem_writew_dyncorex86,"%Ddr%Dd",DREG(EA),DREG(TMPW));
	} else {
		gen_dop_word(DOP_MOV,decode.big_op,&DynRegs[decode.modrm.rm],DREG(TMPW));
	}
	gen_releasereg(DREG(TMPW));
}

static void dyn_enter(void) {
	gen_releasereg(DREG(ESP));
	gen_releasereg(DREG(EBP));
	Bitu bytes=decode_fetchw();
	Bitu level=decode_fetchb();
	gen_call_function((void *)&CPU_ENTER,"%Id%Id%Id",decode.big_op,bytes,level);
}

static void dyn_leave(void) {
	gen_protectflags();
	gen_dop_word_var(DOP_MOV,true,DREG(TMPW),&cpu.stack.mask);
	gen_sop_word(SOP_NOT,true,DREG(TMPW));
	gen_dop_word(DOP_AND,true,DREG(ESP),DREG(TMPW));
	gen_dop_word(DOP_MOV,true,DREG(TMPW),DREG(EBP));
	gen_dop_word_var(DOP_AND,true,DREG(TMPW),&cpu.stack.mask);
	gen_dop_word(DOP_OR,true,DREG(ESP),DREG(TMPW));