expr2tc from_integer(const mp_integer &int_value, const type2tc &type)
{
switch(type->type_id)
{
case type2t::bool_id:
return !int_value.is_zero() ? gen_true_expr() : gen_false_expr();
case type2t::unsignedbv_id:
case type2t::signedbv_id:
return constant_int2tc(type, int_value);
case type2t::fixedbv_id:
{
constant_fixedbv2tc f(fixedbvt(fixedbv_spect(
to_fixedbv_type(type).width, to_fixedbv_type(type).integer_bits)));
f->value.from_integer(int_value);
return f;
}
case type2t::floatbv_id:
{
constant_floatbv2tc f(ieee_floatt(ieee_float_spect(
to_floatbv_type(type).fraction, to_floatbv_type(type).exponent)));
f->value.from_integer(int_value);
return f;
}
default:
abort();
}
}
void goto_symext::track_new_pointer(
const expr2tc &ptr_obj,
const type2tc &new_type,
const expr2tc &size)
{
// Also update all the accounting data.
// Mark that object as being dynamic, in the __ESBMC_is_dynamic array
type2tc sym_type =
type2tc(new array_type2t(get_bool_type(), expr2tc(), true));
symbol2tc sym(sym_type, dyn_info_arr_name);
index2tc idx(get_bool_type(), sym, ptr_obj);
expr2tc truth = gen_true_expr();
symex_assign(code_assign2tc(idx, truth), true);
symbol2tc valid_sym(sym_type, valid_ptr_arr_name);
index2tc valid_index_expr(get_bool_type(), valid_sym, ptr_obj);
truth = gen_true_expr();
symex_assign(code_assign2tc(valid_index_expr, truth), true);
symbol2tc dealloc_sym(sym_type, deallocd_arr_name);
index2tc dealloc_index_expr(get_bool_type(), dealloc_sym, ptr_obj);
expr2tc falseity = gen_false_expr();
symex_assign(code_assign2tc(dealloc_index_expr, falseity), true);
type2tc sz_sym_type =
type2tc(new array_type2t(pointer_type2(), expr2tc(), true));
symbol2tc sz_sym(sz_sym_type, alloc_size_arr_name);
index2tc sz_index_expr(get_bool_type(), sz_sym, ptr_obj);
expr2tc object_size_exp;
if(is_nil_expr(size))
{
try
{
mp_integer object_size = type_byte_size(new_type);
object_size_exp =
constant_int2tc(pointer_type2(), object_size.to_ulong());
}
catch(array_type2t::dyn_sized_array_excp *e)
{
object_size_exp = typecast2tc(pointer_type2(), e->size);
}
}
else
{
object_size_exp = size;
}
symex_assign(code_assign2tc(sz_index_expr, object_size_exp), true);
}
smt_astt array_sym_smt_ast::update(
smt_convt *ctx,
smt_astt value,
unsigned int idx,
expr2tc idx_expr) const
{
const array_type2t array_type = to_array_type(sort->get_tuple_type());
const struct_union_data &data = ctx->get_type_def(array_type.subtype);
expr2tc index;
if(is_nil_expr(idx_expr))
{
index =
constant_int2tc(ctx->make_array_domain_type(array_type), BigInt(idx));
}
else
{
index = idx_expr;
}
std::string name = ctx->mk_fresh_name("tuple_array_update::") + ".";
tuple_sym_smt_astt result = new array_sym_smt_ast(ctx, sort, name);
// Iterate over all members. They are _all_ indexed and updated.
unsigned int i = 0;
for(auto const &it : data.members)
{
type2tc arrtype(
new array_type2t(it, array_type.array_size, array_type.size_is_infinite));
// Project and update a field in 'this'
smt_astt field = project(ctx, i);
smt_astt resval = value->project(ctx, i);
smt_astt updated = field->update(ctx, resval, 0, index);
// Now equality it into the result object
smt_astt res_field = result->project(ctx, i);
updated->assign(ctx, res_field);
i++;
}
return result;
}
smt_astt
smt_convt::convert_byte_update(const expr2tc &expr)
{
const byte_update2t &data = to_byte_update2t(expr);
assert(is_scalar_type(data.source_value) && "Byte update only works on "
"scalar variables now");
if (!is_constant_int2t(data.source_offset)) {
expr2tc source = data.source_value;
unsigned int src_width = source->type->get_width();
if (!is_bv_type(source))
source = typecast2tc(get_uint_type(src_width), source);
expr2tc offs = data.source_offset;
// Endian-ness: if we're in non-"native" endian-ness mode, then flip the
// offset distance. The rest of these calculations will still apply.
if (data.big_endian) {
auto data_size = type_byte_size(*source->type);
constant_int2tc data_size_expr(source->type, data_size - 1);
sub2tc sub(source->type, data_size_expr, offs);
offs = sub;
}
if (offs->type->get_width() != src_width)
offs = typecast2tc(get_uint_type(src_width), offs);
expr2tc update = data.update_value;
if (update->type->get_width() != src_width)
update = typecast2tc(get_uint_type(src_width), update);
// The approach: mask, shift and or. XXX, byte order?
// Massively inefficient.
expr2tc eight = constant_int2tc(get_uint_type(src_width), BigInt(8));
expr2tc effs = constant_int2tc(eight->type, BigInt(255));
offs = mul2tc(eight->type, offs, eight);
expr2tc shl = shl2tc(offs->type, effs, offs);
expr2tc noteffs = bitnot2tc(effs->type, shl);
source = bitand2tc(source->type, source, noteffs);
expr2tc shl2 = shl2tc(offs->type, update, offs);
return convert_ast(bitor2tc(offs->type, shl2, source));
}
// We are merging two values: an 8 bit update value, and a larger source
// value that we will have to merge it into. Start off by collecting
// information about the source values and their widths.
assert(is_number_type(data.source_value->type) && "Byte update of unsupported data type");
smt_astt value, src_value;
unsigned int width_op0, width_op2, src_offset;
value = convert_ast(data.update_value);
src_value = convert_ast(data.source_value);
width_op2 = data.update_value->type->get_width();
width_op0 = data.source_value->type->get_width();
src_offset = to_constant_int2t(data.source_offset).constant_value.to_ulong();
// Flip location if we're in big-endian mode
if (data.big_endian) {
unsigned int data_size =
type_byte_size(*data.source_value->type).to_ulong() - 1;
src_offset = data_size - src_offset;
}
if (int_encoding) {
std::cerr << "Can't byte update in integer mode; rerun in bitvector mode"
<< std::endl;
abort();
}
// Assertion some of our assumptions, which broadly mean that we'll only work
// on bytes that are going into non-byte words
assert(width_op2 == 8 && "Can't byte update non-byte operations");
assert(width_op2 != width_op0 && "Can't byte update bytes, sorry");
smt_astt top, middle, bottom;
// Build in three parts: the most significant bits, any in the middle, and
// the bottom, of the reconstructed / merged output. There might not be a
// middle if the update byte is at the top or the bottom.
unsigned int top_of_update = (8 * src_offset) + 8;
unsigned int bottom_of_update = (8 * src_offset);
if (top_of_update == width_op0) {
top = value;
} else {
smt_sortt s = mk_sort(SMT_SORT_BV, width_op0 - top_of_update, false);
top = mk_extract(src_value, width_op0 - 1, top_of_update, s);
}
if (top == value) {
middle = NULL;
} else {
middle = value;
}
if (src_offset == 0) {
middle = NULL;
bottom = value;
} else {
smt_sortt s = mk_sort(SMT_SORT_BV, bottom_of_update, false);
bottom = mk_extract(src_value, bottom_of_update - 1, 0, s);
}
// Concatenate the top and bottom, and possible middle, together.
smt_astt concat;
if (middle != NULL) {
smt_sortt s = mk_sort(SMT_SORT_BV, width_op0 - bottom_of_update, false);
concat = mk_func_app(s, SMT_FUNC_CONCAT, top, middle);
} else {
concat = top;
}
return mk_func_app(src_value->sort, SMT_FUNC_CONCAT, concat, bottom);
}
