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/*****************************************************************************
sc_fxnum.cpp -
Original Author: Martin Janssen, Synopsys, Inc.
*****************************************************************************/
/*****************************************************************************
MODIFICATION LOG - modifiers, enter your name, affiliation, date and
changes you are making here.
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// $Log: sc_fxnum.cpp,v $
// Revision 1.3 2011/01/19 18:57:40 acg
// Andy Goodrich: changes for IEEE_1666_2011.
//
// Revision 1.2 2010/12/07 20:09:08 acg
// Andy Goodrich: Philipp Hartmann's constructor disambiguation fix
//
// Revision 1.1.1.1 2006/12/15 20:20:04 acg
// SystemC 2.3
//
// Revision 1.3 2006/01/13 18:53:57 acg
// Andy Goodrich: added $Log command so that CVS comments are reproduced in
// the source.
//
#include <cmath>
#include "systemc/ext/dt/fx/messages.hh"
#include "systemc/ext/dt/fx/sc_fxnum.hh"
namespace sc_dt
{
// ----------------------------------------------------------------------------
// CLASS : sc_fxnum_bitref
//
// Proxy class for bit-selection in class sc_fxnum, behaves like sc_bit.
// ----------------------------------------------------------------------------
bool sc_fxnum_bitref::get() const { return m_num.get_bit(m_idx); }
void sc_fxnum_bitref::set(bool high) { m_num.set_bit(m_idx, high); }
// print or dump content
void sc_fxnum_bitref::print(::std::ostream &os) const { os << get(); }
void
sc_fxnum_bitref::scan(::std::istream &is)
{
bool b;
is >> b;
*this = b;
}
void
sc_fxnum_bitref::dump(::std::ostream &os) const
{
os << "sc_fxnum_bitref" << ::std::endl;
os << "(" << ::std::endl;
os << "num = ";
m_num.dump(os);
os << "idx = " << m_idx << ::std::endl;
os << ")" << ::std::endl;
}
// ----------------------------------------------------------------------------
// CLASS : sc_fxnum_fast_bitref
//
// Proxy class for bit-selection in class sc_fxnum_fast, behaves like sc_bit.
// ----------------------------------------------------------------------------
bool sc_fxnum_fast_bitref::get() const { return m_num.get_bit(m_idx); }
void sc_fxnum_fast_bitref::set(bool high) { m_num.set_bit(m_idx, high); }
// print or dump content
void sc_fxnum_fast_bitref::print(::std::ostream &os) const { os << get(); }
void
sc_fxnum_fast_bitref::scan(::std::istream &is)
{
bool b;
is >> b;
*this = b;
}
void
sc_fxnum_fast_bitref::dump(::std::ostream &os) const
{
os << "sc_fxnum_fast_bitref" << ::std::endl;
os << "(" << ::std::endl;
os << "num = ";
m_num.dump(os);
os << "idx = " << m_idx << ::std::endl;
os << ")" << ::std::endl;
}
// ----------------------------------------------------------------------------
// CLASS : sc_fxnum_subref
//
// Proxy class for part-selection in class sc_fxnum,
// behaves like sc_bv_base.
// ----------------------------------------------------------------------------
bool
sc_fxnum_subref::get() const
{
return m_num.get_slice(m_from, m_to, m_bv);
}
bool
sc_fxnum_subref::set()
{
return m_num.set_slice(m_from, m_to, m_bv);
}
// print or dump content
void
sc_fxnum_subref::print(::std::ostream &os) const
{
get();
m_bv.print(os);
}
void
sc_fxnum_subref::scan(::std::istream &is)
{
m_bv.scan(is);
set();
}
void
sc_fxnum_subref::dump(::std::ostream &os) const
{
os << "sc_fxnum_subref" << ::std::endl;
os << "(" << ::std::endl;
os << "num = ";
m_num.dump(os);
os << "from = " << m_from << ::std::endl;
os << "to = " << m_to << ::std::endl;
os << ")" << ::std::endl;
}
// ----------------------------------------------------------------------------
// CLASS : sc_fxnum_fast_subref
//
// Proxy class for part-selection in class sc_fxnum_fast,
// behaves like sc_bv_base.
// ----------------------------------------------------------------------------
bool
sc_fxnum_fast_subref::get() const
{
return m_num.get_slice(m_from, m_to, m_bv);
}
bool
sc_fxnum_fast_subref::set()
{
return m_num.set_slice(m_from, m_to, m_bv);
}
// print or dump content
void
sc_fxnum_fast_subref::print(::std::ostream &os) const
{
get();
m_bv.print(os);
}
void
sc_fxnum_fast_subref::scan(::std::istream &is)
{
m_bv.scan(is);
set();
}
void
sc_fxnum_fast_subref::dump(::std::ostream &os) const
{
os << "sc_fxnum_fast_subref" << ::std::endl;
os << "(" << ::std::endl;
os << "num = ";
m_num.dump(os);
os << "from = " << m_from << ::std::endl;
os << "to = " << m_to << ::std::endl;
os << ")" << ::std::endl;
}
// ----------------------------------------------------------------------------
// CLASS : sc_fxnum
//
// Base class for the fixed-point types; arbitrary precision.
// ----------------------------------------------------------------------------
// explicit conversion to character string
const std::string
sc_fxnum::to_string() const
{
return std::string(m_rep->to_string(SC_DEC, -1, SC_F, &m_params));
}
const std::string
sc_fxnum::to_string(sc_numrep numrep) const
{
return std::string(m_rep->to_string(numrep, -1, SC_F, &m_params));
}
const std::string
sc_fxnum::to_string(sc_numrep numrep, bool w_prefix) const
{
return std::string(m_rep->to_string(numrep, (w_prefix ? 1 : 0),
SC_F, &m_params));
}
const std::string
sc_fxnum::to_string(sc_fmt fmt) const
{
return std::string(m_rep->to_string(SC_DEC, -1, fmt, &m_params));
}
const std::string
sc_fxnum::to_string(sc_numrep numrep, sc_fmt fmt) const
{
return std::string(m_rep->to_string(numrep, -1, fmt, &m_params));
}
const std::string
sc_fxnum::to_string(sc_numrep numrep, bool w_prefix, sc_fmt fmt) const
{
return std::string(m_rep->to_string(numrep, (w_prefix ? 1 : 0),
fmt, &m_params));
}
const std::string
sc_fxnum::to_dec() const
{
return std::string(m_rep->to_string(SC_DEC, -1, SC_F, &m_params));
}
const std::string
sc_fxnum::to_bin() const
{
return std::string(m_rep->to_string(SC_BIN, -1, SC_F, &m_params));
}
const std::string
sc_fxnum::to_oct() const
{
return std::string(m_rep->to_string(SC_OCT, -1, SC_F, &m_params));
}
const std::string
sc_fxnum::to_hex() const
{
return std::string(m_rep->to_string(SC_HEX, -1, SC_F, &m_params));
}
// print or dump content
void
sc_fxnum::print(::std::ostream &os) const
{
os << m_rep->to_string(SC_DEC, -1, SC_F, &m_params);
}
void
sc_fxnum::scan(::std::istream &is)
{
std::string s;
is >> s;
*this = s.c_str();
}
void
sc_fxnum::dump(::std::ostream &os) const
{
os << "sc_fxnum" << ::std::endl;
os << "(" << ::std::endl;
os << "rep = ";
m_rep->dump(os);
os << "params = ";
m_params.dump(os);
os << "q_flag = " << m_q_flag << ::std::endl;
os << "o_flag = " << m_o_flag << ::std::endl;
// TO BE COMPLETED
// os << "observer = ";
// if (m_observer != 0)
// m_observer->dump(os);
// else
// os << "0" << ::std::endl;
os << ")" << ::std::endl;
}
sc_fxnum_observer *
sc_fxnum::lock_observer() const
{
SC_ASSERT_(m_observer != 0, "lock observer failed");
sc_fxnum_observer * tmp = m_observer;
m_observer = 0;
return tmp;
}
void
sc_fxnum::unlock_observer(sc_fxnum_observer *observer_) const
{
SC_ASSERT_(observer_ != 0, "unlock observer failed");
m_observer = observer_;
}
// ----------------------------------------------------------------------------
// CLASS : sc_fxnum_fast
//
// Base class for the fixed-point types; limited precision.
// ----------------------------------------------------------------------------
static void
quantization(double &c, const scfx_params &params, bool &q_flag)
{
int fwl = params.wl() - params.iwl();
double scale = scfx_pow2(fwl);
double val = scale * c;
double int_part;
double frac_part = modf(val, &int_part);
q_flag = (frac_part != 0.0);
if (q_flag) {
val = int_part;
switch (params.q_mode()) {
case SC_TRN: // truncation
{
if (c < 0.0)
val -= 1.0;
break;
}
case SC_RND: // rounding to plus infinity
{
if (frac_part >= 0.5)
val += 1.0;
else if (frac_part < -0.5)
val -= 1.0;
break;
}
case SC_TRN_ZERO: // truncation to zero
{
break;
}
case SC_RND_INF: // rounding to infinity
{
if (frac_part >= 0.5)
val += 1.0;
else if (frac_part <= -0.5)
val -= 1.0;
break;
}
case SC_RND_CONV: // convergent rounding
{
if (frac_part > 0.5 ||
(frac_part == 0.5 && fmod(int_part, 2.0) != 0.0)) {
val += 1.0;
} else if (frac_part < -0.5 ||
(frac_part == -0.5 && fmod(int_part, 2.0) != 0.0)) {
val -= 1.0;
}
break;
}
case SC_RND_ZERO: // rounding to zero
{
if (frac_part > 0.5)
val += 1.0;
else if (frac_part < -0.5)
val -= 1.0;
break;
}
case SC_RND_MIN_INF: // rounding to minus infinity
{
if (frac_part > 0.5)
val += 1.0;
else if (frac_part <= -0.5)
val -= 1.0;
break;
}
default:
;
}
}
val /= scale;
c = val;
}
static void
overflow(double &c, const scfx_params &params, bool &o_flag)
{
int iwl = params.iwl();
int fwl = params.wl() - iwl;
double full_circle = scfx_pow2(iwl);
double resolution = scfx_pow2(-fwl);
double low, high;
if (params.enc() == SC_TC_) {
high = full_circle / 2.0 - resolution;
if (params.o_mode() == SC_SAT_SYM)
low = - high;
else
low = - full_circle / 2.0;
} else {
low = 0.0;
high = full_circle - resolution;
}
double val = c;
sc_fxval_fast c2(c);
bool under = (val < low);
bool over = (val > high);
o_flag = (under || over);
if (o_flag) {
switch (params.o_mode()) {
case SC_WRAP: // wrap-around
{
int n_bits = params.n_bits();
if (n_bits == 0) {
// wrap-around all 'wl' bits
val -= floor(val / full_circle) * full_circle;
if (val > high)
val -= full_circle;
} else if (n_bits < params.wl()) {
double X = scfx_pow2(iwl - n_bits);
// wrap-around least significant 'wl - n_bits' bits
val -= floor(val / X) * X;
if (val > (X - resolution))
val -= X;
// saturate most significant 'n_bits' bits
if (under) {
val += low;
} else {
if (params.enc() == SC_TC_)
val += full_circle / 2.0 - X;
else
val += full_circle - X;
}
} else {
// saturate all 'wl' bits
if (under)
val = low;
else
val = high;
}
break;
}
case SC_SAT: // saturation
case SC_SAT_SYM: // symmetrical saturation
{
if (under)
val = low;
else
val = high;
break;
}
case SC_SAT_ZERO: // saturation to zero
{
val = 0.0;
break;
}
case SC_WRAP_SM: // sign magnitude wrap-around
{
SC_ERROR_IF_(params.enc() == SC_US_,
sc_core::SC_ID_WRAP_SM_NOT_DEFINED_);
int n_bits = params.n_bits();
if (n_bits == 0) {
// invert conditionally
if (c2.get_bit(iwl) != c2.get_bit(iwl - 1))
val = -val - resolution;
// wrap-around all 'wl' bits
val -= floor(val / full_circle) * full_circle;
if (val > high)
val -= full_circle;
} else if (n_bits == 1) {
// invert conditionally
if (c2.is_neg() != c2.get_bit(iwl - 1))
val = -val - resolution;
// wrap-around all 'wl' bits
val -= floor(val / full_circle) * full_circle;
if (val > high)
val -= full_circle;
} else if (n_bits < params.wl()) {
// invert conditionally
if (c2.is_neg() == c2.get_bit(iwl - n_bits))
val = -val - resolution;
double X = scfx_pow2(iwl - n_bits);
// wrap-around least significant 'wl - n_bits' bits
val -= floor(val / X) * X;
if (val > (X - resolution))
val -= X;
// saturate most significant 'n_bits' bits
if (under)
val += low;
else
val += full_circle / 2.0 - X;
} else {
// saturate all 'wl' bits
if (under)
val = low;
else
val = high;
}
break;
}
default:
;
}
c = val;
}
}
void
sc_fxnum_fast::cast()
{
scfx_ieee_double id(m_val);
SC_ERROR_IF_(id.is_nan() || id.is_inf(), sc_core::SC_ID_INVALID_FX_VALUE_);
if (m_params.cast_switch() == SC_ON) {
m_q_flag = false;
m_o_flag = false;
// check for special cases
if (id.is_zero()) {
if (id.negative() != 0)
m_val = -m_val;
return;
}
// perform casting
sc_dt::quantization(m_val, m_params, m_q_flag);
sc_dt::overflow(m_val, m_params, m_o_flag);
// check for special case: -0
id = m_val;
if (id.is_zero() && id.negative() != 0) {
m_val = -m_val;
}
// check for special case: NaN of Inf
if (id.is_nan() || id.is_inf()) {
m_val = 0.0;
}
}
}
// defined in sc_fxval.cpp;
extern const char* to_string(const scfx_ieee_double &, sc_numrep, int, sc_fmt,
const scfx_params * =0);
// explicit conversion to character string
const std::string
sc_fxnum_fast::to_string() const
{
return std::string(sc_dt::to_string(m_val, SC_DEC, -1, SC_F, &m_params));
}
const std::string
sc_fxnum_fast::to_string(sc_numrep numrep) const
{
return std::string(sc_dt::to_string(m_val, numrep, -1, SC_F, &m_params));
}
const std::string
sc_fxnum_fast::to_string(sc_numrep numrep, bool w_prefix) const
{
return std::string(sc_dt::to_string(m_val, numrep, (w_prefix ? 1 : 0),
SC_F, &m_params));
}
const std::string
sc_fxnum_fast::to_string(sc_fmt fmt) const
{
return std::string(sc_dt::to_string(m_val, SC_DEC, -1, fmt, &m_params));
}
const std::string
sc_fxnum_fast::to_string(sc_numrep numrep, sc_fmt fmt) const
{
return std::string(sc_dt::to_string(m_val, numrep, -1, fmt, &m_params));
}
const std::string
sc_fxnum_fast::to_string(sc_numrep numrep, bool w_prefix, sc_fmt fmt) const
{
return std::string(sc_dt::to_string(m_val, numrep, (w_prefix ? 1 : 0),
fmt, &m_params));
}
const std::string
sc_fxnum_fast::to_dec() const
{
return std::string(sc_dt::to_string(m_val, SC_DEC, -1, SC_F, &m_params));
}
const std::string
sc_fxnum_fast::to_bin() const
{
return std::string(sc_dt::to_string(m_val, SC_BIN, -1, SC_F, &m_params));
}
const std::string
sc_fxnum_fast::to_oct() const
{
return std::string(sc_dt::to_string(m_val, SC_OCT, -1, SC_F, &m_params));
}
const std::string
sc_fxnum_fast::to_hex() const
{
return std::string(sc_dt::to_string(m_val, SC_HEX, -1, SC_F, &m_params));
}
// print or dump content
void
sc_fxnum_fast::print(::std::ostream &os) const
{
os << sc_dt::to_string(m_val, SC_DEC, -1, SC_F, &m_params);
}
void
sc_fxnum_fast::scan(::std::istream &is)
{
std::string s;
is >> s;
*this = s.c_str();
}
void
sc_fxnum_fast::dump(::std::ostream &os) const
{
os << "sc_fxnum_fast" << ::std::endl;
os << "(" << ::std::endl;
os << "val = " << m_val << ::std::endl;
os << "params = ";
m_params.dump(os);
os << "q_flag = " << m_q_flag << ::std::endl;
os << "o_flag = " << m_o_flag << ::std::endl;
// TO BE COMPLETED
// os << "observer = ";
// if (m_observer != 0)
// m_observer->dump(os);
// else
// os << "0" << ::std::endl;
os << ")" << ::std::endl;
}
// internal use only;
bool
sc_fxnum_fast::get_bit(int i) const
{
scfx_ieee_double id(m_val);
if (id.is_zero() || id.is_nan() || id.is_inf())
return false;
// convert to two's complement
unsigned int m0 = id.mantissa0();
unsigned int m1 = id.mantissa1();
if (id.is_normal())
m0 += 1U << 20;
if (id.negative() != 0) {
m0 = ~ m0;
m1 = ~ m1;
unsigned int tmp = m1;
m1 += 1U;
if (m1 <= tmp)
m0 += 1U;
}
// get the right bit
int j = i - id.exponent();
if ((j += 20) >= 32)
return ((m0 & 1U << 31) != 0);
else if (j >= 0)
return ((m0 & 1U << j) != 0);
else if ((j += 32) >= 0)
return ((m1 & 1U << j) != 0);
else
return false;
}
bool
sc_fxnum_fast::set_bit(int i, bool high)
{
scfx_ieee_double id(m_val);
if (id.is_nan() || id.is_inf())
return false;
if (high) {
if (get_bit(i))
return true;
if (m_params.enc() == SC_TC_ && i == m_params.iwl() - 1)
m_val -= scfx_pow2(i);
else
m_val += scfx_pow2(i);
} else {
if (!get_bit(i))
return true;
if (m_params.enc() == SC_TC_ && i == m_params.iwl() - 1)
m_val += scfx_pow2(i);
else
m_val -= scfx_pow2(i);
}
return true;
}
bool
sc_fxnum_fast::get_slice(int i, int j, sc_bv_base &bv) const
{
scfx_ieee_double id(m_val);
if (id.is_nan() || id.is_inf())
return false;
// convert to two's complement
unsigned int m0 = id.mantissa0();
unsigned int m1 = id.mantissa1();
if (id.is_normal())
m0 += 1U << 20;
if (id.negative() != 0) {
m0 = ~ m0;
m1 = ~ m1;
unsigned int tmp = m1;
m1 += 1U;
if (m1 <= tmp)
m0 += 1U;
}
// get the bits
int l = j;
for (int k = 0; k < bv.length(); ++ k) {
bool b = false;
int n = l - id.exponent();
if ((n += 20) >= 32)
b = ((m0 & 1U << 31) != 0);
else if (n >= 0)
b = ((m0 & 1U << n) != 0);
else if ((n += 32) >= 0)
b = ((m1 & 1U << n) != 0);
bv[k] = b;
if (i >= j)
++l;
else
--l;
}
return true;
}
bool
sc_fxnum_fast::set_slice(int i, int j, const sc_bv_base &bv)
{
scfx_ieee_double id(m_val);
if (id.is_nan() || id.is_inf())
return false;
// set the bits
int l = j;
for (int k = 0; k < bv.length(); ++k) {
if (bv[k].to_bool()) {
if (!get_bit(l)) {
if (m_params.enc() == SC_TC_ && l == m_params.iwl() - 1)
m_val -= scfx_pow2(l);
else
m_val += scfx_pow2(l);
}
} else {
if (get_bit(l)) {
if (m_params.enc() == SC_TC_ && l == m_params.iwl() - 1)
m_val += scfx_pow2(l);
else
m_val -= scfx_pow2(l);
}
}
if (i >= j)
++l;
else
--l;
}
return true;
}
sc_fxnum_fast_observer *
sc_fxnum_fast::lock_observer() const
{
SC_ASSERT_(m_observer != 0, "lock observer failed");
sc_fxnum_fast_observer *tmp = m_observer;
m_observer = 0;
return tmp;
}
void
sc_fxnum_fast::unlock_observer(sc_fxnum_fast_observer *observer_) const
{
SC_ASSERT_(observer_ != 0, "unlock observer failed");
m_observer = observer_;
}
} // namespace sc_dt