void boolbvt::convert_with_bv(
const typet &type,
const exprt &op1,
const exprt &op2,
const bvt &prev_bv,
bvt &next_bv)
{
literalt l=convert(op2);
mp_integer op1_value;
if(!to_integer(op1, op1_value))
{
next_bv=prev_bv;
if(op1_value<next_bv.size())
next_bv[integer2size_t(op1_value)]=l;
return;
}
typet counter_type=op1.type();
for(std::size_t i=0; i<prev_bv.size(); i++)
{
exprt counter=from_integer(i, counter_type);
literalt eq_lit=convert(equal_exprt(op1, counter));
next_bv[i]=prop.lselect(eq_lit, l, prev_bv[i]);
}
}
exprt path_symex_statet::array_theory(const exprt &src, bool propagate)
{
// top-level constant-sized arrays only right now
if(src.id()==ID_index)
{
const index_exprt &index_expr=to_index_expr(src);
exprt index_tmp1=read(index_expr.index(), propagate);
exprt index_tmp2=simplify_expr(index_tmp1, var_map.ns);
if(!index_tmp2.is_constant())
{
const array_typet &array_type=to_array_type(index_expr.array().type());
const typet &subtype=array_type.subtype();
if(array_type.size().is_constant())
{
mp_integer size;
if(to_integer(array_type.size(), size))
throw "failed to convert array size";
std::size_t size_int=integer2size_t(size);
exprt result=nil_exprt();
// split it up
for(std::size_t i=0; i<size_int; ++i)
{
exprt index=from_integer(i, index_expr.index().type());
exprt new_src=index_exprt(index_expr.array(), index, subtype);
if(result.is_nil())
result=new_src;
else
{
equal_exprt index_equal(index_expr.index(), index);
result=if_exprt(index_equal, new_src, result);
}
}
return result; // done
}
else
{
// TODO: variable-sized array
}
}
}
return src;
}
void interpretert::read(
mp_integer address,
std::vector<mp_integer> &dest) const
{
// copy memory region
for(auto &d : dest)
{
mp_integer value;
if(address<memory.size())
value=memory[integer2size_t(address)].value;
else
value=0;
d=value;
++address;
}
}
bvt float_utilst::rounder(const unbiased_floatt &src)
{
// incoming: some fraction (with explicit 1),
// some exponent without bias
// outgoing: rounded, with right size, with hidden bit, bias
bvt aligned_fraction=src.fraction,
aligned_exponent=src.exponent;
{
std::size_t exponent_bits=
std::max((std::size_t)integer2size_t(address_bits(spec.f)),
(std::size_t)spec.e)+1;
// before normalization, make sure exponent is large enough
if(aligned_exponent.size()<exponent_bits)
{
// sign extend
aligned_exponent=
bv_utils.sign_extension(aligned_exponent, exponent_bits);
}
}
// align it!
normalization_shift(aligned_fraction, aligned_exponent);
denormalization_shift(aligned_fraction, aligned_exponent);
unbiased_floatt result;
result.fraction=aligned_fraction;
result.exponent=aligned_exponent;
result.sign=src.sign;
result.NaN=src.NaN;
result.infinity=src.infinity;
round_fraction(result);
round_exponent(result);
return pack(bias(result));
}
void c_typecheck_baset::do_designated_initializer(
exprt &result,
designatort &designator,
const exprt &value,
bool force_constant)
{
assert(!designator.empty());
if(value.id()==ID_designated_initializer)
{
assert(value.operands().size()==1);
designator=
make_designator(
designator.front().type,
static_cast<const exprt &>(value.find(ID_designator)));
assert(!designator.empty());
return do_designated_initializer(
result, designator, value.op0(), force_constant);
}
exprt *dest=&result;
// first phase: follow given designator
for(size_t i=0; i<designator.size(); i++)
{
size_t index=designator[i].index;
const typet &type=designator[i].type;
const typet &full_type=follow(type);
if(full_type.id()==ID_array ||
full_type.id()==ID_vector)
{
if(index>=dest->operands().size())
{
if(full_type.id()==ID_array &&
(to_array_type(full_type).size().is_zero() ||
to_array_type(full_type).size().is_nil()))
{
// we are willing to grow an incomplete or zero-sized array
exprt zero=
zero_initializer(
full_type.subtype(),
value.source_location(),
*this,
get_message_handler());
dest->operands().resize(integer2size_t(index)+1, zero);
// todo: adjust type!
}
else
{
err_location(value);
error() << "array index designator " << index
<< " out of bounds (" << dest->operands().size()
<< ")" << eom;
throw 0;
}
}
dest=&(dest->operands()[integer2size_t(index)]);
}
else if(full_type.id()==ID_struct)
{
const struct_typet::componentst &components=
to_struct_type(full_type).components();
if(index>=dest->operands().size())
{
err_location(value);
error() << "structure member designator " << index
<< " out of bounds (" << dest->operands().size()
<< ")" << eom;
throw 0;
}
assert(index<components.size());
assert(components[index].type().id()!=ID_code &&
!components[index].get_is_padding());
dest=&(dest->operands()[index]);
}
else if(full_type.id()==ID_union)
{
const union_typet &union_type=to_union_type(full_type);
const union_typet::componentst &components=
union_type.components();
assert(index<components.size());
const union_typet::componentt &component=union_type.components()[index];
if(dest->id()==ID_union &&
dest->get(ID_component_name)==component.get_name())
{
// Already right union component. We can initialize multiple submembers,
// so do not overwrite this.
}
else
{
// Note that gcc issues a warning if the union component is switched.
// Build a union expression from given component.
union_exprt union_expr(type);
union_expr.op()=
zero_initializer(
component.type(),
value.source_location(),
*this,
get_message_handler());
union_expr.add_source_location()=value.source_location();
union_expr.set_component_name(component.get_name());
*dest=union_expr;
}
dest=&(dest->op0());
}
else
assert(false);
}
// second phase: assign value
// for this, we may need to go down, adding to the designator
while(true)
{
// see what type we have to initialize
const typet &type=designator.back().subtype;
const typet &full_type=follow(type);
assert(full_type.id()!=ID_symbol);
// do we initialize a scalar?
if(full_type.id()!=ID_struct &&
full_type.id()!=ID_union &&
full_type.id()!=ID_array &&
full_type.id()!=ID_vector)
{
// The initializer for a scalar shall be a single expression,
// * optionally enclosed in braces. *
if(value.id()==ID_initializer_list &&
value.operands().size()==1)
*dest=do_initializer_rec(value.op0(), type, force_constant);
else
*dest=do_initializer_rec(value, type, force_constant);
assert(full_type==follow(dest->type()));
return; // done
}
// union? The component in the zero initializer might
// not be the first one.
if(full_type.id()==ID_union)
{
const union_typet &union_type=to_union_type(full_type);
const union_typet::componentst &components=
union_type.components();
if(!components.empty())
{
const union_typet::componentt &component=
union_type.components().front();
union_exprt union_expr(type);
union_expr.op()=
zero_initializer(
component.type(),
value.source_location(),
*this,
get_message_handler());
union_expr.add_source_location()=value.source_location();
union_expr.set_component_name(component.get_name());
*dest=union_expr;
}
}
// see what initializer we are given
if(value.id()==ID_initializer_list)
{
*dest=do_initializer_rec(value, type, force_constant);
return; // done
}
else if(value.id()==ID_string_constant)
{
// We stop for initializers that are string-constants,
// which are like arrays. We only do so if we are to
// initialize an array of scalars.
if(full_type.id()==ID_array &&
(follow(full_type.subtype()).id()==ID_signedbv ||
follow(full_type.subtype()).id()==ID_unsignedbv))
{
*dest=do_initializer_rec(value, type, force_constant);
return; // done
}
}
else if(follow(value.type())==full_type)
{
// a struct/union/vector can be initialized directly with
// an expression of the right type. This doesn't
// work with arrays, unfortunately.
if(full_type.id()==ID_struct ||
full_type.id()==ID_union ||
full_type.id()==ID_vector)
{
*dest=value;
return; // done
}
}
assert(full_type.id()==ID_struct ||
full_type.id()==ID_union ||
full_type.id()==ID_array ||
full_type.id()==ID_vector);
// we are initializing a compound type, and enter it!
// this may change the type, full_type might not be valid anymore
const typet dest_type=full_type;
designator_enter(type, designator);
if(dest->operands().empty())
{
err_location(value);
error() << "cannot initialize type `"
<< to_string(dest_type) << "' using value `"
<< to_string(value) << "'" << eom;
throw 0;
}
dest=&(dest->op0());
// we run into another loop iteration
}
}
void c_typecheck_baset::designator_enter(
const typet &type,
designatort &designator)
{
designatort::entryt entry;
entry.type=type;
entry.index=0;
const typet &full_type=follow(type);
if(full_type.id()==ID_struct)
{
const struct_typet &struct_type=to_struct_type(full_type);
entry.size=struct_type.components().size();
entry.subtype.make_nil();
for(struct_typet::componentst::const_iterator
it=struct_type.components().begin();
it!=struct_type.components().end();
++it)
{
if(it->type().id()!=ID_code &&
!it->get_is_padding())
{
entry.subtype=it->type();
break;
}
++entry.index;
}
}
else if(full_type.id()==ID_union)
{
const union_typet &union_type=to_union_type(full_type);
if(union_type.components().empty())
{
entry.size=0;
entry.subtype.make_nil();
}
else
{
// The default is to unitialize using the first member of the
// union.
entry.size=1;
entry.subtype=union_type.components().front().type();
}
}
else if(full_type.id()==ID_array)
{
const array_typet &array_type=to_array_type(full_type);
if(array_type.size().is_nil())
{
entry.size=0;
entry.subtype=array_type.subtype();
}
else
{
mp_integer array_size;
if(to_integer(array_type.size(), array_size))
{
err_location(array_type.size());
error() << "array has non-constant size `"
<< to_string(array_type.size()) << "'" << eom;
throw 0;
}
entry.size=integer2size_t(array_size);
entry.subtype=array_type.subtype();
}
}
else if(full_type.id()==ID_vector)
{
const vector_typet &vector_type=to_vector_type(full_type);
mp_integer vector_size;
if(to_integer(vector_type.size(), vector_size))
{
err_location(vector_type.size());
error() << "vector has non-constant size `"
<< to_string(vector_type.size()) << "'" << eom;
throw 0;
}
entry.size=integer2size_t(vector_size);
entry.subtype=vector_type.subtype();
}
else
assert(false);
designator.push_entry(entry);
}
exprt boolbvt::bv_get_unbounded_array(const exprt &expr) const
{
// first, try to get size
const typet &type=expr.type();
const exprt &size_expr=to_array_type(type).size();
exprt size=simplify_expr(get(size_expr), ns);
// no size, give up
if(size.is_nil()) return nil_exprt();
// get the numeric value, unless it's infinity
mp_integer size_mpint;
if(size.id()!=ID_infinity)
{
if(to_integer(size, size_mpint))
return nil_exprt();
// simple sanity check
if(size_mpint<0)
return nil_exprt();
}
else
size_mpint=0;
// search array indices
typedef std::map<mp_integer, exprt> valuest;
valuest values;
{
std::size_t number;
if(arrays.get_number(expr, number))
return nil_exprt();
// get root
number=arrays.find_number(number);
assert(number<index_map.size());
index_mapt::const_iterator it=index_map.find(number);
assert(it!=index_map.end());
const index_sett &index_set=it->second;
for(index_sett::const_iterator it1=
index_set.begin();
it1!=index_set.end();
it1++)
{
index_exprt index;
index.type()=type.subtype();
index.array()=expr;
index.index()=*it1;
exprt value=bv_get_cache(index);
exprt index_value=bv_get_cache(*it1);
if(!index_value.is_nil())
{
mp_integer index_mpint;
if(!to_integer(index_value, index_mpint))
{
if(value.is_nil())
values[index_mpint]=exprt(ID_unknown, type.subtype());
else
values[index_mpint]=value;
}
}
}
}
exprt result;
if(size_mpint>100 || size.id()==ID_infinity)
{
result=exprt("array-list", type);
result.type().set(ID_size, integer2string(size_mpint));
result.operands().reserve(values.size()*2);
for(valuest::const_iterator it=values.begin();
it!=values.end();
it++)
{
exprt index=from_integer(it->first, size.type());
result.copy_to_operands(index, it->second);
}
}
else
{
// set the size
result=exprt(ID_array, type);
result.type().set(ID_size, size);
std::size_t size_int=integer2size_t(size_mpint);
// allocate operands
result.operands().resize(size_int);
for(std::size_t i=0; i<size_int; i++)
result.operands()[i]=exprt(ID_unknown);
// search uninterpreted functions
for(valuest::iterator it=values.begin();
it!=values.end();
it++)
if(it->first>=0 && it->first<size_mpint)
result.operands()[integer2size_t(it->first)].swap(it->second);
}
return result;
}
bvt boolbvt::convert_byte_update(const byte_update_exprt &expr)
{
if(expr.operands().size()!=3)
throw "byte_update takes three operands";
const exprt &op=expr.op0();
const exprt &offset_expr=expr.offset();
const exprt &value=expr.value();
bool little_endian;
if(expr.id()==ID_byte_update_little_endian)
little_endian=true;
else if(expr.id()==ID_byte_update_big_endian)
little_endian=false;
else
assert(false);
bvt bv=convert_bv(op);
const bvt &value_bv=convert_bv(value);
std::size_t update_width=value_bv.size();
std::size_t byte_width=8;
if(update_width>bv.size())
update_width=bv.size();
// see if the byte number is constant
mp_integer index;
if(!to_integer(offset_expr, index))
{
// yes!
mp_integer offset=index*8;
if(offset+update_width>mp_integer(bv.size()) || offset<0)
{
// out of bounds
}
else
{
if(little_endian)
{
for(std::size_t i=0; i<update_width; i++)
bv[integer2size_t(offset+i)]=value_bv[i];
}
else
{
endianness_mapt map_op(op.type(), false, ns);
endianness_mapt map_value(value.type(), false, ns);
std::size_t offset_i=integer2unsigned(offset);
for(std::size_t i=0; i<update_width; i++)
{
size_t index_op=map_op.map_bit(offset_i+i);
size_t index_value=map_value.map_bit(i);
assert(index_op<bv.size());
assert(index_value<value_bv.size());
bv[index_op]=value_bv[index_value];
}
}
}
return bv;
}
// byte_update with variable index
for(std::size_t offset=0; offset<bv.size(); offset+=byte_width)
{
// index condition
equal_exprt equality;
equality.lhs()=offset_expr;
equality.rhs()=from_integer(offset/byte_width, offset_expr.type());
literalt equal=convert(equality);
endianness_mapt map_op(op.type(), little_endian, ns);
endianness_mapt map_value(value.type(), little_endian, ns);
for(std::size_t bit=0; bit<update_width; bit++)
if(offset+bit<bv.size())
{
std::size_t bv_o=map_op.map_bit(offset+bit);
std::size_t value_bv_o=map_value.map_bit(bit);
bv[bv_o]=prop.lselect(equal, value_bv[value_bv_o], bv[bv_o]);
}
}
return bv;
}
exprt path_symex_statet::expand_structs_and_arrays(const exprt &src)
{
#ifdef DEBUG
std::cout << "expand_structs_and_arrays: "
<< from_expr(var_map.ns, "", src) << '\n';
#endif
const typet &src_type=var_map.ns.follow(src.type());
if(src_type.id()==ID_struct) // src is a struct
{
const struct_typet &struct_type=to_struct_type(src_type);
const struct_typet::componentst &components=struct_type.components();
struct_exprt result(src.type());
result.operands().resize(components.size());
// split it up into components
for(unsigned i=0; i<components.size(); i++)
{
const typet &subtype=components[i].type();
const irep_idt &component_name=components[i].get_name();
exprt new_src;
if(src.id()==ID_struct) // struct constructor?
{
assert(src.operands().size()==components.size());
new_src=src.operands()[i];
}
else
new_src=member_exprt(src, component_name, subtype);
// recursive call
result.operands()[i]=expand_structs_and_arrays(new_src);
}
return result; // done
}
else if(src_type.id()==ID_array) // src is an array
{
const array_typet &array_type=to_array_type(src_type);
const typet &subtype=array_type.subtype();
if(array_type.size().is_constant())
{
mp_integer size;
if(to_integer(array_type.size(), size))
throw "failed to convert array size";
std::size_t size_int=integer2size_t(size);
array_exprt result(array_type);
result.operands().resize(size_int);
// split it up into elements
for(std::size_t i=0; i<size_int; ++i)
{
exprt index=from_integer(i, array_type.size().type());
exprt new_src=index_exprt(src, index, subtype);
// array constructor?
if(src.id()==ID_array)
new_src=simplify_expr(new_src, var_map.ns);
// recursive call
result.operands()[i]=expand_structs_and_arrays(new_src);
}
return result; // done
}
else
{
// TODO: variable-sized array
}
}
else if(src_type.id()==ID_vector) // src is a vector
{
const vector_typet &vector_type=to_vector_type(src_type);
const typet &subtype=vector_type.subtype();
if(!vector_type.size().is_constant())
throw "vector with non-constant size";
mp_integer size;
if(to_integer(vector_type.size(), size))
throw "failed to convert vector size";
std::size_t size_int=integer2size_t(size);
vector_exprt result(vector_type);
exprt::operandst &operands=result.operands();
operands.resize(size_int);
// split it up into elements
for(std::size_t i=0; i<size_int; ++i)
{
exprt index=from_integer(i, vector_type.size().type());
exprt new_src=index_exprt(src, index, subtype);
// vector constructor?
if(src.id()==ID_vector)
new_src=simplify_expr(new_src, var_map.ns);
// recursive call
operands[i]=expand_structs_and_arrays(new_src);
}
return result; // done
}
return src;
}
bool simplify_exprt::simplify_index(exprt &expr)
{
bool result=true;
// extra arithmetic optimizations
const exprt &index=to_index_expr(expr).index();
const exprt &array=to_index_expr(expr).array();
if(index.id()==ID_div &&
index.operands().size()==2)
{
if(index.op0().id()==ID_mult &&
index.op0().operands().size()==2 &&
index.op0().op1()==index.op1())
{
exprt tmp=index.op0().op0();
expr.op1()=tmp;
result=false;
}
else if(index.op0().id()==ID_mult &&
index.op0().operands().size()==2 &&
index.op0().op0()==index.op1())
{
exprt tmp=index.op0().op1();
expr.op1()=tmp;
result=false;
}
}
if(array.id()==ID_lambda)
{
// simplify (lambda i: e)(x) to e[i/x]
const exprt &lambda_expr=array;
if(lambda_expr.operands().size()!=2)
return true;
if(expr.op1().type()==lambda_expr.op0().type())
{
exprt tmp=lambda_expr.op1();
replace_expr(lambda_expr.op0(), expr.op1(), tmp);
expr.swap(tmp);
return false;
}
}
else if(array.id()==ID_with)
{
// we have (a WITH [i:=e])[j]
const exprt &with_expr=array;
if(with_expr.operands().size()!=3)
return true;
if(with_expr.op1()==expr.op1())
{
// simplify (e with [i:=v])[i] to v
exprt tmp=with_expr.op2();
expr.swap(tmp);
return false;
}
else
{
// Turn (a with i:=x)[j] into (i==j)?x:a[j].
// watch out that the type of i and j might be different.
equal_exprt equality_expr(expr.op1(), with_expr.op1());
if(equality_expr.lhs().type()!=equality_expr.rhs().type())
equality_expr.rhs().make_typecast(equality_expr.lhs().type());
simplify_inequality(equality_expr);
index_exprt new_index_expr;
new_index_expr.type()=expr.type();
new_index_expr.array()=with_expr.op0();
new_index_expr.index()=expr.op1();
simplify_index(new_index_expr); // recursive call
if(equality_expr.is_true())
{
expr=with_expr.op2();
return false;
}
else if(equality_expr.is_false())
{
expr.swap(new_index_expr);
return false;
}
if_exprt if_expr(equality_expr, with_expr.op2(), new_index_expr);
simplify_if(if_expr);
expr.swap(if_expr);
return false;
}
}
else if(array.id()==ID_constant ||
array.id()==ID_array)
{
mp_integer i;
if(to_integer(expr.op1(), i))
{
}
else if(i<0 || i>=array.operands().size())
{
// out of bounds
}
else
{
// ok
exprt tmp=array.operands()[integer2size_t(i)];
expr.swap(tmp);
return false;
}
}
else if(array.id()==ID_string_constant)
{
mp_integer i;
const irep_idt &value=array.get(ID_value);
if(to_integer(expr.op1(), i))
{
}
else if(i<0 || i>value.size())
{
// out of bounds
}
else
{
// terminating zero?
char v=(i==value.size())?0:value[integer2size_t(i)];
exprt tmp=from_integer(v, expr.type());
expr.swap(tmp);
return false;
}
}
else if(array.id()==ID_array_of)
{
if(array.operands().size()==1)
{
exprt tmp=array.op0();
expr.swap(tmp);
return false;
}
}
else if(array.id()=="array-list")
{
// These are index/value pairs, alternating.
for(size_t i=0; i<array.operands().size()/2; i++)
{
exprt tmp_index=array.operands()[i*2];
tmp_index.make_typecast(index.type());
simplify(tmp_index);
if(tmp_index==index)
{
exprt tmp=array.operands()[i*2+1];
expr.swap(tmp);
return false;
}
}
}
else if(array.id()==ID_byte_extract_little_endian ||
array.id()==ID_byte_extract_big_endian)
{
const typet &array_type=ns.follow(array.type());
if(array_type.id()==ID_array)
{
// This rewrites byte_extract(s, o, array_type)[i]
// to byte_extract(s, o+offset, sub_type)
mp_integer sub_size=pointer_offset_size(array_type.subtype(), ns);
if(sub_size==-1)
return true;
// add offset to index
mult_exprt offset(from_integer(sub_size, array.op1().type()), index);
plus_exprt final_offset(array.op1(), offset);
simplify_node(final_offset);
exprt result(array.id(), expr.type());
result.copy_to_operands(array.op0(), final_offset);
expr.swap(result);
simplify_rec(expr);
return false;
}
}
else if(array.id()==ID_if)
{
const if_exprt &if_expr=to_if_expr(array);
exprt cond=if_expr.cond();
index_exprt idx_false=to_index_expr(expr);
idx_false.array()=if_expr.false_case();
to_index_expr(expr).array()=if_expr.true_case();
expr=if_exprt(cond, expr, idx_false, expr.type());
simplify_rec(expr);
return false;
}
return result;
}
bool simplify_exprt::simplify_floatbv_typecast(exprt &expr)
{
// These casts usually reduce precision, and thus, usually round.
assert(expr.operands().size()==2);
const typet &dest_type=ns.follow(expr.type());
const typet &src_type=ns.follow(expr.op0().type());
// eliminate redundant casts
if(dest_type==src_type)
{
expr=expr.op0();
return false;
}
exprt op0=expr.op0();
exprt op1=expr.op1(); // rounding mode
// We can soundly re-write (float)((double)x op (double)y)
// to x op y. True for any rounding mode!
#if 0
if(op0.id()==ID_floatbv_div ||
op0.id()==ID_floatbv_mult ||
op0.id()==ID_floatbv_plus ||
op0.id()==ID_floatbv_minus)
{
if(op0.operands().size()==3 &&
op0.op0().id()==ID_typecast &&
op0.op1().id()==ID_typecast &&
op0.op0().operands().size()==1 &&
op0.op1().operands().size()==1 &&
ns.follow(op0.op0().type())==dest_type &&
ns.follow(op0.op1().type())==dest_type)
{
exprt result(op0.id(), expr.type());
result.operands().resize(3);
result.op0()=op0.op0().op0();
result.op1()=op0.op1().op0();
result.op2()=op1;
simplify_node(result);
expr.swap(result);
return false;
}
}
#endif
// constant folding
if(op0.is_constant() && op1.is_constant())
{
mp_integer rounding_mode;
if(!to_integer(op1, rounding_mode))
{
if(src_type.id()==ID_floatbv)
{
if(dest_type.id()==ID_floatbv) // float to float
{
ieee_floatt result(to_constant_expr(op0));
result.rounding_mode=(ieee_floatt::rounding_modet)integer2size_t(rounding_mode);
result.change_spec(to_floatbv_type(dest_type));
expr=result.to_expr();
return false;
}
else if(dest_type.id()==ID_signedbv ||
dest_type.id()==ID_unsignedbv)
{
if(rounding_mode==ieee_floatt::ROUND_TO_ZERO)
{
ieee_floatt result(to_constant_expr(op0));
result.rounding_mode=(ieee_floatt::rounding_modet)integer2size_t(rounding_mode);
mp_integer value=result.to_integer();
expr=from_integer(value, dest_type);
return false;
}
}
}
else if(src_type.id()==ID_signedbv ||
src_type.id()==ID_unsignedbv)
{
mp_integer value;
if(!to_integer(op0, value))
{
if(dest_type.id()==ID_floatbv) // int to float
{
ieee_floatt result;
result.rounding_mode=(ieee_floatt::rounding_modet)integer2size_t(rounding_mode);
result.spec=to_floatbv_type(dest_type);
result.from_integer(value);
expr=result.to_expr();
return false;
}
}
}
}
}
#if 0
// (T)(a?b:c) --> a?(T)b:(T)c
if(expr.op0().id()==ID_if &&
expr.op0().operands().size()==3)
{
exprt tmp_op1=binary_exprt(expr.op0().op1(), ID_floatbv_typecast, expr.op1(), dest_type);
exprt tmp_op2=binary_exprt(expr.op0().op2(), ID_floatbv_typecast, expr.op1(), dest_type);
simplify_floatbv_typecast(tmp_op1);
simplify_floatbv_typecast(tmp_op2);
expr=if_exprt(expr.op0().op0(), tmp_op1, tmp_op2, dest_type);
simplify_if(expr);
return false;
}
#endif
return true;
}
bvt boolbvt::convert_shift(const binary_exprt &expr)
{
const irep_idt &type_id=expr.type().id();
if(type_id!=ID_unsignedbv &&
type_id!=ID_signedbv &&
type_id!=ID_floatbv &&
type_id!=ID_pointer &&
type_id!=ID_bv &&
type_id!=ID_verilog_signedbv &&
type_id!=ID_verilog_unsignedbv)
return conversion_failed(expr);
std::size_t width=boolbv_width(expr.type());
if(width==0)
return conversion_failed(expr);
if(expr.operands().size()!=2)
throw "shifting takes two operands";
const bvt &op=convert_bv(expr.op0());
if(op.size()!=width)
throw "convert_shift: unexpected operand 0 width";
bv_utilst::shiftt shift;
if(expr.id()==ID_shl)
shift=bv_utilst::shiftt::LEFT;
else if(expr.id()==ID_ashr)
shift=bv_utilst::shiftt::ARIGHT;
else if(expr.id()==ID_lshr)
shift=bv_utilst::shiftt::LRIGHT;
else
throw "unexpected shift operator";
// we allow a constant as shift distance
if(expr.op1().is_constant())
{
mp_integer i;
if(to_integer(expr.op1(), i))
throw "convert_shift: failed to convert constant";
std::size_t distance;
if(i<0 || i>std::numeric_limits<signed>::max())
distance=0;
else
distance=integer2size_t(i);
if(type_id==ID_verilog_signedbv ||
type_id==ID_verilog_unsignedbv)
distance*=2;
return bv_utils.shift(op, shift, distance);
}
else
{
const bvt &distance=convert_bv(expr.op1());
return bv_utils.shift(op, shift, distance);
}
}
std::string ieee_floatt::to_string_decimal(std::size_t precision) const
{
std::string result;
if(sign_flag)
result+='-';
if((NaN_flag || infinity_flag) && !sign_flag)
result+='+';
// special cases
if(NaN_flag)
result+="NaN";
else if(infinity_flag)
result+="inf";
else if(is_zero())
{
result+='0';
// add zeros, if needed
if(precision>0)
{
result+='.';
for(std::size_t i=0; i<precision; i++)
result+='0';
}
}
else
{
mp_integer _exponent, _fraction;
extract_base2(_fraction, _exponent);
// convert to base 10
if(_exponent>=0)
{
result+=integer2string(_fraction*power(2, _exponent));
// add dot and zeros, if needed
if(precision>0)
{
result+='.';
for(std::size_t i=0; i<precision; i++)
result+='0';
}
}
else
{
#if 1
mp_integer position=-_exponent;
// 10/2=5 -- this makes it base 10
_fraction*=power(5, position);
// apply rounding
if(position>precision)
{
mp_integer r=power(10, position-precision);
mp_integer remainder=_fraction%r;
_fraction/=r;
// not sure if this is the right kind of rounding here
if(remainder>=r/2)
++_fraction;
position=precision;
}
std::string tmp=integer2string(_fraction);
// pad with zeros from the front, if needed
while(mp_integer(tmp.size())<=position) tmp="0"+tmp;
std::size_t dot=tmp.size()-integer2size_t(position);
result+=std::string(tmp, 0, dot)+'.';
result+=std::string(tmp, dot, std::string::npos);
// append zeros if needed
for(mp_integer i=position; i<precision; ++i)
result+='0';
#else
result+=integer2string(_fraction);
if(_exponent!=0)
result+="*2^"+integer2string(_exponent);
#endif
}
}
return result;
}
void boolbvt::convert_update_rec(
const exprt::operandst &designators,
std::size_t d,
const typet &type,
std::size_t offset,
const exprt &new_value,
bvt &bv)
{
if(type.id()==ID_symbol)
convert_update_rec(
designators, d, ns.follow(type), offset, new_value, bv);
if(d>=designators.size())
{
// done
bvt new_value_bv=convert_bv(new_value);
std::size_t new_value_width=boolbv_width(type);
if(new_value_width!=new_value_bv.size())
throw "convert_update_rec: unexpected new_value size";
// update
for(std::size_t i=0; i<new_value_width; i++)
{
assert(offset+i<bv.size());
bv[offset+i]=new_value_bv[i];
}
return;
}
const exprt &designator=designators[d];
if(designator.id()==ID_index_designator)
{
if(type.id()!=ID_array)
throw "update: index designator needs array";
if(designator.operands().size()!=1)
throw "update: index designator takes one operand";
bvt index_bv=convert_bv(designator.op0());
const array_typet &array_type=to_array_type(type);
const typet &subtype=ns.follow(array_type.subtype());
std::size_t element_size=boolbv_width(subtype);
// iterate over array
mp_integer size;
if(to_integer(array_type.size(), size))
throw "update: failed to get array size";
bvt tmp_bv=bv;
for(std::size_t i=0; i!=integer2size_t(size); ++i)
{
std::size_t new_offset=offset+i*element_size;
convert_update_rec(
designators, d+1, subtype, new_offset, new_value, tmp_bv);
bvt const_bv=bv_utils.build_constant(i, index_bv.size());
literalt equal=bv_utils.equal(const_bv, index_bv);
for(std::size_t j=0; j<element_size; j++)
{
std::size_t idx=new_offset+j;
assert(idx<bv.size());
bv[idx]=prop.lselect(equal, tmp_bv[idx], bv[idx]);
}
}
}
else if(designator.id()==ID_member_designator)
{
const irep_idt &component_name=designator.get(ID_component_name);
if(type.id()==ID_struct)
{
const struct_typet &struct_type=
to_struct_type(type);
std::size_t struct_offset=0;
struct_typet::componentt component;
component.make_nil();
const struct_typet::componentst &components=
struct_type.components();
for(struct_typet::componentst::const_iterator
it=components.begin();
it!=components.end();
it++)
{
const typet &subtype=it->type();
std::size_t sub_width=boolbv_width(subtype);
if(it->get_name()==component_name)
{
component=*it;
break; // done
}
struct_offset+=sub_width;
}
if(component.is_nil())
throw "update: failed to find struct component";
const typet &new_type=ns.follow(component.type());
std::size_t new_offset=offset+struct_offset;
// recursive call
convert_update_rec(
designators, d+1, new_type, new_offset, new_value, bv);
}
else if(type.id()==ID_union)
{
const union_typet &union_type=
to_union_type(type);
const union_typet::componentt &component=
union_type.get_component(component_name);
if(component.is_nil())
throw "update: failed to find union component";
// this only adjusts the type, the offset stays as-is
const typet &new_type=ns.follow(component.type());
// recursive call
convert_update_rec(
designators, d+1, new_type, offset, new_value, bv);
}
else
throw "update: member designator needs struct or union";
}
else
throw "update: unexpected designator";
}
designatort c_typecheck_baset::make_designator(
const typet &src_type,
const exprt &src)
{
assert(!src.operands().empty());
typet type=src_type;
designatort designator;
forall_operands(it, src)
{
const exprt &d_op=*it;
designatort::entryt entry;
entry.type=type;
const typet &full_type=follow(entry.type);
if(full_type.id()==ID_array)
{
if(d_op.id()!=ID_index)
{
err_location(d_op);
error() << "expected array index designator" << eom;
throw 0;
}
assert(d_op.operands().size()==1);
exprt tmp_index=d_op.op0();
make_constant_index(tmp_index);
mp_integer index, size;
if(to_integer(tmp_index, index))
{
err_location(d_op.op0());
error() << "expected constant array index designator" << eom;
throw 0;
}
if(to_array_type(full_type).size().is_nil())
size=0;
else if(to_integer(to_array_type(full_type).size(), size))
{
err_location(d_op.op0());
error() << "expected constant array size" << eom;
throw 0;
}
entry.index=integer2size_t(index);
entry.size=integer2size_t(size);
entry.subtype=full_type.subtype();
}
else if(full_type.id()==ID_struct ||
full_type.id()==ID_union)
{
const struct_union_typet &struct_union_type=
to_struct_union_type(full_type);
if(d_op.id()!=ID_member)
{
err_location(d_op);
error() << "expected member designator" << eom;
throw 0;
}
const irep_idt &component_name=d_op.get(ID_component_name);
if(struct_union_type.has_component(component_name))
{
// a direct member
entry.index=struct_union_type.component_number(component_name);
entry.size=struct_union_type.components().size();
entry.subtype=struct_union_type.components()[entry.index].type();
}
else
{
// We will search for anonymous members,
// in a loop. This isn't supported by gcc, but icc does allow it.
bool found=false, repeat;
typet tmp_type=entry.type;
do
{
repeat=false;
unsigned number=0;
const struct_union_typet::componentst &components=
to_struct_union_type(follow(tmp_type)).components();
for(struct_union_typet::componentst::const_iterator
c_it=components.begin();
c_it!=components.end();
c_it++, number++)
{
if(c_it->get_name()==component_name)
{
// done!
entry.index=number;
entry.size=components.size();
entry.subtype=components[entry.index].type();
entry.type=tmp_type;
}
else if(c_it->get_anonymous() &&
(follow(c_it->type()).id()==ID_struct ||
follow(c_it->type()).id()==ID_union) &&
has_component_rec(
c_it->type(), component_name, *this))
{
entry.index=number;
entry.size=components.size();
entry.subtype=c_it->type();
entry.type=tmp_type;
tmp_type=entry.subtype;
designator.push_entry(entry);
found=repeat=true;
break;
}
}
}
while(repeat);
if(!found)
{
err_location(d_op);
error() << "failed to find struct component `"
<< component_name << "' in initialization of `"
<< to_string(struct_union_type) << "'" << eom;
throw 0;
}
}
}
else
{
err_location(d_op);
error() << "designated initializers cannot initialize `"
<< to_string(full_type) << "'" << eom;
throw 0;
}
type=entry.subtype;
designator.push_entry(entry);
}
assert(!designator.empty());
return designator;
}
exprt c_typecheck_baset::do_initializer_rec(
const exprt &value,
const typet &type,
bool force_constant)
{
const typet &full_type=follow(type);
if(full_type.id()==ID_incomplete_struct)
{
err_location(value);
error() << "type `" << to_string(full_type)
<< "' is still incomplete -- cannot initialize" << eom;
throw 0;
}
if(value.id()==ID_initializer_list)
return do_initializer_list(value, type, force_constant);
if(value.id()==ID_array &&
value.get_bool(ID_C_string_constant) &&
full_type.id()==ID_array &&
(full_type.subtype().id()==ID_signedbv ||
full_type.subtype().id()==ID_unsignedbv) &&
full_type.subtype().get(ID_width)==value.type().subtype().get(ID_width))
{
exprt tmp=value;
// adjust char type
tmp.type().subtype()=full_type.subtype();
Forall_operands(it, tmp)
it->type()=full_type.subtype();
if(full_type.id()==ID_array &&
to_array_type(full_type).is_complete())
{
// check size
mp_integer array_size;
if(to_integer(to_array_type(full_type).size(), array_size))
{
err_location(value);
error() << "array size needs to be constant, got "
<< to_string(to_array_type(full_type).size()) << eom;
throw 0;
}
if(array_size<0)
{
err_location(value);
error() << "array size must not be negative" << eom;
throw 0;
}
if(mp_integer(tmp.operands().size())>array_size)
{
// cut off long strings. gcc does a warning for this
tmp.operands().resize(integer2size_t(array_size));
tmp.type()=type;
}
else if(mp_integer(tmp.operands().size())<array_size)
{
// fill up
tmp.type()=type;
exprt zero=
zero_initializer(
full_type.subtype(),
value.source_location(),
*this,
get_message_handler());
tmp.operands().resize(integer2size_t(array_size), zero);
}
}
return tmp;
}
if(value.id()==ID_string_constant &&
full_type.id()==ID_array &&
(full_type.subtype().id()==ID_signedbv ||
full_type.subtype().id()==ID_unsignedbv) &&
full_type.subtype().get(ID_width)==char_type().get(ID_width))
{
// will go away, to be replaced by the above block
string_constantt tmp1=to_string_constant(value);
// adjust char type
tmp1.type().subtype()=full_type.subtype();
exprt tmp2=tmp1.to_array_expr();
if(full_type.id()==ID_array &&
to_array_type(full_type).is_complete())
{
// check size
mp_integer array_size;
if(to_integer(to_array_type(full_type).size(), array_size))
{
err_location(value);
error() << "array size needs to be constant, got "
<< to_string(to_array_type(full_type).size()) << eom;
throw 0;
}
if(array_size<0)
{
err_location(value);
error() << "array size must not be negative" << eom;
throw 0;
}
if(mp_integer(tmp2.operands().size())>array_size)
{
// cut off long strings. gcc does a warning for this
tmp2.operands().resize(integer2size_t(array_size));
tmp2.type()=type;
}
else if(mp_integer(tmp2.operands().size())<array_size)
{
// fill up
tmp2.type()=type;
exprt zero=
zero_initializer(
full_type.subtype(),
value.source_location(),
*this,
get_message_handler());
tmp2.operands().resize(integer2size_t(array_size), zero);
}
}
return tmp2;
}
if(full_type.id()==ID_array &&
to_array_type(full_type).size().is_nil())
{
err_location(value);
error() << "type `" << to_string(full_type)
<< "' cannot be initialized with `" << to_string(value)
<< "'" << eom;
throw 0;
}
if(value.id()==ID_designated_initializer)
{
err_location(value);
error() << "type `" << to_string(full_type)
<< "' cannot be initialized with designated initializer"
<< eom;
throw 0;
}
exprt result=value;
implicit_typecast(result, type);
return result;
}
void c_typecheck_baset::typecheck_c_bit_field_type(c_bit_field_typet &type)
{
typecheck_type(type.subtype());
mp_integer i;
{
exprt &width_expr=static_cast<exprt &>(type.add(ID_size));
typecheck_expr(width_expr);
make_constant_index(width_expr);
if(to_integer(width_expr, i))
{
error().source_location=type.source_location();
error() << "failed to convert bit field width" << eom;
throw 0;
}
if(i<0)
{
error().source_location=type.source_location();
error() << "bit field width is negative" << eom;
throw 0;
}
type.set_width(integer2size_t(i));
type.remove(ID_size);
}
const typet &subtype=follow(type.subtype());
std::size_t sub_width=0;
if(subtype.id()==ID_bool)
{
// This is the 'proper' bool.
sub_width=1;
}
else if(subtype.id()==ID_signedbv ||
subtype.id()==ID_unsignedbv ||
subtype.id()==ID_c_bool)
{
sub_width=to_bitvector_type(subtype).get_width();
}
else if(subtype.id()==ID_c_enum_tag)
{
// These point to an enum, which has a sub-subtype,
// which may be smaller or larger than int, and we thus have
// to check.
const typet &c_enum_type=
follow_tag(to_c_enum_tag_type(subtype));
if(c_enum_type.id()==ID_incomplete_c_enum)
{
error().source_location=type.source_location();
error() << "bit field has incomplete enum type" << eom;
throw 0;
}
sub_width=c_enum_type.subtype().get_int(ID_width);
}
else
{
error().source_location=type.source_location();
error() << "bit field with non-integer type: "
<< to_string(subtype) << eom;
throw 0;
}
if(i>sub_width)
{
error().source_location=type.source_location();
error() << "bit field (" << i
<< " bits) larger than type (" << sub_width << " bits)"
<< eom;
throw 0;
}
}
bool simplify_exprt::simplify_floatbv_op(exprt &expr)
{
const typet &type=ns.follow(expr.type());
if(type.id()!=ID_floatbv)
return true;
assert(expr.operands().size()==3);
exprt op0=expr.op0();
exprt op1=expr.op1();
exprt op2=expr.op2(); // rounding mode
assert(ns.follow(op0.type())==type);
assert(ns.follow(op1.type())==type);
// Remember that floating-point addition is _NOT_ associative.
// Thus, we don't re-sort the operands.
// We only merge constants!
if(op0.is_constant() && op1.is_constant() && op2.is_constant())
{
ieee_floatt v0(to_constant_expr(op0));
ieee_floatt v1(to_constant_expr(op1));
mp_integer rounding_mode;
if(!to_integer(op2, rounding_mode))
{
v0.rounding_mode=(ieee_floatt::rounding_modet)integer2size_t(rounding_mode);
v1.rounding_mode=v0.rounding_mode;
ieee_floatt result=v0;
if(expr.id()==ID_floatbv_plus)
result+=v1;
else if(expr.id()==ID_floatbv_minus)
result-=v1;
else if(expr.id()==ID_floatbv_mult)
result*=v1;
else if(expr.id()==ID_floatbv_div)
result/=v1;
else
assert(false);
expr=result.to_expr();
return false;
}
}
// division by one? Exact for all rounding modes.
if (expr.id()==ID_floatbv_div &&
op1.is_constant() && op1.is_one())
{
exprt tmp;
tmp.swap(op0);
expr.swap(tmp);
return false;
}
return true;
}
bool remove_const_function_pointerst::try_resolve_index_of(
const index_exprt &index_expr,
expressionst &out_expressions,
bool &out_is_const)
{
// Get the array(s) it belongs to
expressionst potential_array_exprs;
bool array_const=false;
bool resolved_array=
try_resolve_expression(
index_expr.array(),
potential_array_exprs,
array_const);
if(resolved_array)
{
bool all_possible_const=true;
for(const exprt &potential_array_expr : potential_array_exprs)
{
all_possible_const=
all_possible_const &&
is_const_type(potential_array_expr.type().subtype());
if(potential_array_expr.id()==ID_array)
{
// Get the index if we can
mp_integer value;
if(try_resolve_index_value(index_expr.index(), value))
{
expressionst array_out_functions;
const exprt &func_expr=
potential_array_expr.operands()[integer2size_t(value)];
bool value_const=false;
bool resolved_value=
try_resolve_expression(func_expr, array_out_functions, value_const);
if(resolved_value)
{
out_expressions.insert(
out_expressions.end(),
array_out_functions.begin(),
array_out_functions.end());
}
else
{
LOG("Failed to resolve array value", func_expr);
return false;
}
}
else
{
// We don't know what index it is,
// but we know the value is from the array
for(const exprt &array_entry : potential_array_expr.operands())
{
expressionst array_contents;
bool is_entry_const;
bool resolved_value=
try_resolve_expression(
array_entry, array_contents, is_entry_const);
if(!resolved_value)
{
LOG("Failed to resolve array value", array_entry);
return false;
}
for(const exprt &resolved_array_entry : array_contents)
{
if(!resolved_array_entry.is_zero())
{
out_expressions.push_back(resolved_array_entry);
}
}
}
}
}
else
{
LOG(
"Squashing index of did not result in an array",
potential_array_expr);
return false;
}
}
out_is_const=all_possible_const || array_const;
return true;
}
else
{
LOG("Failed to squash index of to array expression", index_expr);
return false;
}
}
