erl_arith.c

OTP是开放电信平台的简称

			} else {
			    /*
			     * The result is a a big number.
			     * Allocate a heap fragment and copy the result.
			     * Be careful to allocate exactly what we need
			     * to not leave any holes.
			     */
			    Uint arity;
			    Uint need;
			    
			    ASSERT(is_big(res));
			    hdr = big_res[0];
			    arity = bignum_header_arity(hdr);
			    ASSERT(arity == 1 || arity == 2);
			    need = arity + 1;
			    if (ERTS_NEED_GC(p, need)) {
				erts_garbage_collect(p, need, reg, live);
			    }
			    hp = p->htop;
			    p->htop += need;
			    res = make_big(hp);
			    *hp++ = hdr;
			    *hp++ = big_res[1];
			    if (arity > 1) {
				*hp = big_res[2];
			    }
			    return res;
			}
		    }
		default:
		badarith:
		    p->freason = BADARITH;
		    return THE_NON_VALUE;
		}
	    case TAG_PRIMARY_BOXED:
		hdr = *boxed_val(arg2);
		switch ((hdr & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE) {
		case (_TAG_HEADER_POS_BIG >> _TAG_PRIMARY_SIZE):
		case (_TAG_HEADER_NEG_BIG >> _TAG_PRIMARY_SIZE):
		    if (arg1 == SMALL_ZERO)
			return(SMALL_ZERO);
		    if (arg1 == SMALL_ONE)
			return(arg2);
		    arg1 = small_to_big(signed_val(arg1), tmp_big1);
		    sz = 2 + big_size(arg2);
		    goto do_big;
		case (_TAG_HEADER_FLOAT >> _TAG_PRIMARY_SIZE):
		    f1.fd = signed_val(arg1);
		    GET_DOUBLE(arg2, f2);
		    goto do_float;
		default:
		    goto badarith;
		}
	    }
	default:
	    goto badarith;
	}
    case TAG_PRIMARY_BOXED:
	hdr = *boxed_val(arg1);
	switch ((hdr & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE) {
	case (_TAG_HEADER_POS_BIG >> _TAG_PRIMARY_SIZE):
	case (_TAG_HEADER_NEG_BIG >> _TAG_PRIMARY_SIZE):
	    switch (arg2 & _TAG_PRIMARY_MASK) {
	    case (_TAG_IMMED1_SMALL >> _TAG_PRIMARY_SIZE):
		switch ((arg2 & _TAG_IMMED1_MASK) >> _TAG_PRIMARY_SIZE) {
		case (_TAG_IMMED1_SMALL >> _TAG_PRIMARY_SIZE):
		    if (arg2 == SMALL_ZERO)
			return(SMALL_ZERO);
		    if (arg2 == SMALL_ONE)
			return(arg1);
		    arg2 = small_to_big(signed_val(arg2), tmp_big2);
		    sz = 2 + big_size(arg1);
		    goto do_big;
		default:
		    goto badarith;
		}
	    case TAG_PRIMARY_BOXED:
		hdr = *boxed_val(arg2);
		switch ((hdr & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE) {
		case (_TAG_HEADER_POS_BIG >> _TAG_PRIMARY_SIZE):
		case (_TAG_HEADER_NEG_BIG >> _TAG_PRIMARY_SIZE):
		    sz1 = big_size(arg1);
		    sz2 = big_size(arg2);
		    sz = sz1 + sz2;

		do_big:
		    need_heap = BIG_NEED_SIZE(sz);
		    if (ERTS_NEED_GC(p, need_heap)) {
			erts_garbage_collect(p, need_heap, reg, live+2);
			if (arg1 != make_big(tmp_big1)) {
			    arg1 = reg[live];
			}
			if (arg2 != make_big(tmp_big2)) {
			    arg2 = reg[live+1];
			}
		    }
		    hp = p->htop;
		    p->htop += need_heap;
		    res = big_times(arg1, arg2, hp);
                    trim_heap(p, hp, res);

		    /*
		     * Note that the result must be big in this case, since
		     * at least one operand was big to begin with, and
		     * the absolute value of the other is > 1.
		     */

		    if (is_nil(res)) {
			p->freason = SYSTEM_LIMIT;
			return THE_NON_VALUE;
		    }
		    return res;
		case (_TAG_HEADER_FLOAT >> _TAG_PRIMARY_SIZE):
		    if (big_to_double(arg1, &f1.fd) < 0) {
			goto badarith;
		    }
		    GET_DOUBLE(arg2, f2);
		    goto do_float;
		default:
		    goto badarith;
		}
	    }
	case (_TAG_HEADER_FLOAT >> _TAG_PRIMARY_SIZE):
	    switch (arg2 & _TAG_PRIMARY_MASK) {
	    case TAG_PRIMARY_IMMED1:
		switch ((arg2 & _TAG_IMMED1_MASK) >> _TAG_PRIMARY_SIZE) {
		case (_TAG_IMMED1_SMALL >> _TAG_PRIMARY_SIZE):
		    GET_DOUBLE(arg1, f1);
		    f2.fd = signed_val(arg2);
		    goto do_float;
		default:
		    goto badarith;
		}
	    case TAG_PRIMARY_BOXED:
		hdr = *boxed_val(arg2);
		switch ((hdr & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE) {
		case (_TAG_HEADER_POS_BIG >> _TAG_PRIMARY_SIZE):
		case (_TAG_HEADER_NEG_BIG >> _TAG_PRIMARY_SIZE):
		    GET_DOUBLE(arg1, f1);
		    if (big_to_double(arg2, &f2.fd) < 0) {
			goto badarith;
		    }
		    goto do_float;
		case (_TAG_HEADER_FLOAT >> _TAG_PRIMARY_SIZE):
		    GET_DOUBLE(arg1, f1);
		    GET_DOUBLE(arg2, f2);

		do_float:
		    f1.fd = f1.fd * f2.fd;
		    ERTS_FP_ERROR(p, f1.fd, goto badarith);
		    if (ERTS_NEED_GC(p, FLOAT_SIZE_OBJECT)) {
			erts_garbage_collect(p, FLOAT_SIZE_OBJECT, reg, live);
		    }
		    hp = p->htop;
		    p->htop += FLOAT_SIZE_OBJECT;
		    res = make_float(hp);
		    PUT_DOUBLE(f1, hp);
		    return res;
		default:
		    goto badarith;
		}
	    default:
		goto badarith;
	    }
	}
    default:
	goto badarith;
    }
}

Eterm
erts_gc_mixed_div(Process* p, Eterm* reg, Uint live)
{
    Eterm arg1;
    Eterm arg2;
    FloatDef f1, f2;
    Eterm* hp;
    Eterm hdr;

    arg1 = reg[live];
    arg2 = reg[live+1];
    ERTS_FP_CHECK_INIT(p);
    switch (arg1 & _TAG_PRIMARY_MASK) {
    case TAG_PRIMARY_IMMED1:
	switch ((arg1 & _TAG_IMMED1_MASK) >> _TAG_PRIMARY_SIZE) {
	case (_TAG_IMMED1_SMALL >> _TAG_PRIMARY_SIZE):
	    switch (arg2 & _TAG_PRIMARY_MASK) {
	    case TAG_PRIMARY_IMMED1:
		switch ((arg2 & _TAG_IMMED1_MASK) >> _TAG_PRIMARY_SIZE) {
		case (_TAG_IMMED1_SMALL >> _TAG_PRIMARY_SIZE):
		    f1.fd = signed_val(arg1);
		    f2.fd = signed_val(arg2);
		    goto do_float;
		default:
		badarith:
		    p->freason = BADARITH;
		    return THE_NON_VALUE;
		}
	    case TAG_PRIMARY_BOXED:
		hdr = *boxed_val(arg2);
		switch ((hdr & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE) {
		case (_TAG_HEADER_POS_BIG >> _TAG_PRIMARY_SIZE):
		case (_TAG_HEADER_NEG_BIG >> _TAG_PRIMARY_SIZE):
		    f1.fd = signed_val(arg1);
		    if (big_to_double(arg2, &f2.fd) < 0) {
			goto badarith;
		    }
		    goto do_float;
		case (_TAG_HEADER_FLOAT >> _TAG_PRIMARY_SIZE):
		    f1.fd = signed_val(arg1);
		    GET_DOUBLE(arg2, f2);
		    goto do_float;
		default:
		    goto badarith;
		}
	    }
	default:
	    goto badarith;
	}
    case TAG_PRIMARY_BOXED:
	hdr = *boxed_val(arg1);
	switch ((hdr & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE) {
	case (_TAG_HEADER_POS_BIG >> _TAG_PRIMARY_SIZE):
	case (_TAG_HEADER_NEG_BIG >> _TAG_PRIMARY_SIZE):
	    switch (arg2 & _TAG_PRIMARY_MASK) {
	    case (_TAG_IMMED1_SMALL >> _TAG_PRIMARY_SIZE):
		switch ((arg2 & _TAG_IMMED1_MASK) >> _TAG_PRIMARY_SIZE) {
		case (_TAG_IMMED1_SMALL >> _TAG_PRIMARY_SIZE):
		    if (big_to_double(arg1, &f1.fd) < 0) {
			goto badarith;
		    }
		    f2.fd = signed_val(arg2);
		    goto do_float;
		default:
		    goto badarith;
		}
	    case TAG_PRIMARY_BOXED:
		hdr = *boxed_val(arg2);
		switch ((hdr & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE) {
		case (_TAG_HEADER_POS_BIG >> _TAG_PRIMARY_SIZE):
		case (_TAG_HEADER_NEG_BIG >> _TAG_PRIMARY_SIZE):
		    if (big_to_double(arg1, &f1.fd) < 0 ||
			big_to_double(arg2, &f2.fd) < 0) {
			goto badarith;
		    }
		    goto do_float;
		case (_TAG_HEADER_FLOAT >> _TAG_PRIMARY_SIZE):
		    if (big_to_double(arg1, &f1.fd) < 0) {
			goto badarith;
		    }
		    GET_DOUBLE(arg2, f2);
		    goto do_float;
		default:
		    goto badarith;
		}
	    }
	case (_TAG_HEADER_FLOAT >> _TAG_PRIMARY_SIZE):
	    switch (arg2 & _TAG_PRIMARY_MASK) {
	    case TAG_PRIMARY_IMMED1:
		switch ((arg2 & _TAG_IMMED1_MASK) >> _TAG_PRIMARY_SIZE) {
		case (_TAG_IMMED1_SMALL >> _TAG_PRIMARY_SIZE):
		    GET_DOUBLE(arg1, f1);
		    f2.fd = signed_val(arg2);
		    goto do_float;
		default:
		    goto badarith;
		}
	    case TAG_PRIMARY_BOXED:
		hdr = *boxed_val(arg2);
		switch ((hdr & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE) {
		case (_TAG_HEADER_POS_BIG >> _TAG_PRIMARY_SIZE):
		case (_TAG_HEADER_NEG_BIG >> _TAG_PRIMARY_SIZE):
		    GET_DOUBLE(arg1, f1);
		    if (big_to_double(arg2, &f2.fd) < 0) {
			goto badarith;
		    }
		    goto do_float;
		case (_TAG_HEADER_FLOAT >> _TAG_PRIMARY_SIZE):
		    GET_DOUBLE(arg1, f1);
		    GET_DOUBLE(arg2, f2);

		do_float:
		    f1.fd = f1.fd / f2.fd;
		    ERTS_FP_ERROR(p, f1.fd, goto badarith);
		    if (ERTS_NEED_GC(p, FLOAT_SIZE_OBJECT)) {
			erts_garbage_collect(p, FLOAT_SIZE_OBJECT, reg, live);
		    }
		    hp = p->htop;
		    p->htop += FLOAT_SIZE_OBJECT;
		    PUT_DOUBLE(f1, hp);
		    return make_float(hp);
		default:
		    goto badarith;
		}
	    default:
		goto badarith;
	    }
	}
    default:
	goto badarith;
    }
}

Eterm
erts_gc_int_div(Process* p, Eterm* reg, Uint live)
{
    Eterm arg1;
    Eterm arg2;
    Eterm tmp_big1[2];
    Eterm tmp_big2[2];
    int ires;

    arg1 = reg[live];
    arg2 = reg[live+1];
    switch (NUMBER_CODE(arg1, arg2)) {
    case SMALL_SMALL:
	/* This case occurs if the most negative fixnum is divided by -1. */
	ASSERT(arg2 == make_small(-1));
	arg1 = small_to_big(signed_val(arg1), tmp_big1);
	/*FALLTHROUGH*/
    case BIG_SMALL:
	arg2 = small_to_big(signed_val(arg2), tmp_big2);
	goto L_big_div;
    case SMALL_BIG:
	if (arg1 != make_small(MIN_SMALL)) {
	    return SMALL_ZERO;
	}
	arg1 = small_to_big(signed_val(arg1), tmp_big1);
	/*FALLTHROUGH*/
    case BIG_BIG:
    L_big_div:
	ires = big_ucomp(arg1, arg2);
	if (ires < 0) {
	    arg1 = SMALL_ZERO;
	} else if (ires == 0) {
	    arg1 = (big_sign(arg1) == big_sign(arg2)) ?
		SMALL_ONE : SMALL_MINUS_ONE;
	} else {
	    Eterm* hp;
	    int i = big_size(arg1);
	    Uint need;

	    ires = big_size(arg2);
	    need = BIG_NEED_SIZE(i-ires+1) + BIG_NEED_SIZE(i);
	    if (ERTS_NEED_GC(p, need)) {
		erts_garbage_collect(p, need, reg, live+2);
		if (arg1 != make_big(tmp_big1)) {
		    arg1 = reg[live];
		}
		if (arg2 != make_big(tmp_big2)) {
		    arg2 = reg[live+1];
		}
	    }
	    hp = p->htop;
	    p->htop += need;
	    arg1 = big_div(arg1, arg2, hp);
	    trim_heap(p, hp, arg1);
	    if (is_nil(arg1)) {
		p->freason = SYSTEM_LIMIT;
		return THE_NON_VALUE;
	    }
	}
	return arg1;
    default:
	p->freason = BADARITH;
	return THE_NON_VALUE;
    }
}

Eterm
erts_gc_int_rem(Process* p, Eterm* reg, Uint live)
{
    Eterm arg1;
    Eterm arg2;
    Eterm tmp_big1[2];
    Eterm tmp_big2[2];
    int ires;

    arg1 = reg[live];
    arg2 = reg[live+1];
    switch (NUMBER_CODE(arg1, arg2)) {
    case BIG_SMALL:
	arg2 = small_to_big(signed_val(arg2), tmp_big2);
	goto L_big_rem;
    case SMALL_BIG:
	if (arg1 != make_small(MIN_SMALL)) {
	    return arg1;
	}
	arg1 = small_to_big(signed_val(arg1), tmp_big1);
	/*FALLTHROUGH*/
    case BIG_BIG:
    L_big_rem:
	ires = big_ucomp(arg1, arg2);
	if (ires == 0) {
	    arg1 = SMALL_ZERO;
	} else if (ires > 0) {
	    Eterm* hp;
	    Uint need = BIG_NEED_SIZE(big_size(arg1));

	    if (ERTS_NEED_GC(p, need)) {
		erts_garbage_collect(p, need, reg, live+2);
		if (arg1 != make_big(tmp_big1)) {
		    arg1 = reg[live];
		}
		if (arg2 != make_big(tmp_big2)) {
		    arg2 = reg[live+1];
		}
	    }
	    hp = p->htop;
	    p->htop += need;
	    arg1 = big_rem(arg1, arg2, hp);
	    trim_heap(p, hp, arg1);
	    if (is_nil(arg1)) {
		p->freason = SYSTEM_LIMIT;
		return THE_NON_VALUE;
	    }
	}
	return arg1;
    default:
	p->freason = BADARITH;
	return THE_NON_VALUE;
    }
}

#define DEFINE_GC_LOGIC_FUNC(func)						\
Eterm erts_gc_##func(Process* p, Eterm* reg, Uint live)				\
{										\
    Eterm arg1;									\
    Eterm arg2;									\
    Eterm tmp_big1[2];								\
    Eterm tmp_big2[2];								\
    Eterm* hp;									\
    int need;									\
										\
    arg1 = reg[live];								\
    arg2 = reg[live+1];								\
    switch (NUMBER_CODE(arg1, arg2)) {						\
    case SMALL_BIG:								\
	arg1 = small_to_big(signed_val(arg1), tmp_big1);			\
	need = BIG_NEED_SIZE(big_size(arg2) + 1);				\
	if (ERTS_NEED_GC(p, need)) {						\
	    erts_garbage_collect(p, need, reg, live+2);				\
	    arg2 = reg[live+1];							\
	}									\
	break;									\
    case BIG_SMALL:								\
	arg2 = small_to_big(signed_val(arg2), tmp_big2);			\
	need = BIG_NEED_SIZE(big_size(arg1) + 1);				\
	if (ERTS_NEED_GC(p, need)) {						\
	    erts_garbage_collect(p, need, reg, live+2);				\
	    arg1 = reg[live];							\
	}									\
	break;									\
    case BIG_BIG:								\
	need = BIG_NEED_SIZE(MAX(big_size(arg1), big_size(arg2)) + 1);		\
	if (ERTS_NEED_GC(p, need)) {						\
	    erts_garbage_collect(p, need, reg, live+2);				\
	    arg1 = reg[live];							\
	    arg2 = reg[live+1];							\
	}									\
	break;									\
    default:									\
	p->freason = BADARITH;							\
	return THE_NON_VALUE;							\
    }										\
    hp = p->htop;								\
    p->htop += need;								\
    arg1 = big_##func(arg1, arg2, hp);						\
    trim_heap(p, hp, arg1);							\
    return arg1;								\
}

DEFINE_GC_LOGIC_FUNC(band)
DEFINE_GC_LOGIC_FUNC(bor)
DEFINE_GC_LOGIC_FUNC(bxor)

Eterm erts_gc_bnot(Process* p, Eterm* reg, Uint live)
{
    Eterm result;
    Eterm arg;
    Uint need;
    Eterm* bigp;

    arg = reg[live];
    if (is_not_big(arg)) {
	p->freason = BADARITH;
	return NIL;
    } else {
	need = BIG_NEED_SIZE(big_size(arg)+1);
	if (ERTS_NEED_GC(p, need)) {
	    erts_garbage_collect(p, need, reg, live+1);
	    arg = reg[live];
	}
	bigp = p->htop;
	p->htop += need;
	result = big_bnot(arg, bigp);
	trim_heap(p, bigp, result);
	if (is_nil(result)) {
	    p->freason = SYSTEM_LIMIT;
	    return NIL;
	}
    }
    return result;
} 

#endif