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/*
* Copyright (c) 2001-2010 Stephen Williams (steve@icarus.com)
*
* This source code is free software; you can redistribute it
* and/or modify it in source code form under the terms of the GNU
* General Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
# include "config.h"
# include <cstdlib>
# include "netlist.h"
# include "netmisc.h"
# include "PExpr.h"
# include "pform_types.h"
# include "ivl_assert.h"
NetNet* add_to_net(Design*des, NetNet*sig, long val)
{
if (val == 0)
return sig;
#if 0
NetScope*scope = sig->scope();
unsigned long abs_val = (val >= 0)? val : (-val);
unsigned width = sig->pin_count();
verinum val_v (abs_val, width);
NetConst*val_c = new NetConst(scope, scope->local_symbol(), val_v);
NetNet*val_s = new NetNet(scope, scope->local_symbol(),
NetNet::IMPLICIT, width);
val_s->local_flag(true);
NetNet*res = new NetNet(scope, scope->local_symbol(),
NetNet::IMPLICIT, width);
res->local_flag(true);
NetAddSub*add = new NetAddSub(scope, scope->local_symbol(), width);
for (unsigned idx = 0 ; idx < width ; idx += 1)
connect(sig->pin(idx), add->pin_DataA(idx));
for (unsigned idx = 0 ; idx < width ; idx += 1)
connect(val_c->pin(idx), add->pin_DataB(idx));
for (unsigned idx = 0 ; idx < width ; idx += 1)
connect(val_s->pin(idx), add->pin_DataB(idx));
for (unsigned idx = 0 ; idx < width ; idx += 1)
connect(res->pin(idx), add->pin_Result(idx));
if (val < 0)
add->attribute(perm_string::literal("LPM_Direction"), verinum("SUB"));
else
add->attribute(perm_string::literal("LPM_Direction"), verinum("ADD"));
des->add_node(add);
des->add_node(val_c);
return res;
#else
cerr << sig->get_fileline() << ": XXXX: Forgot how to implement add_to_net" << endl;
return 0;
#endif
}
NetNet* sub_net_from(Design*des, NetScope*scope, long val, NetNet*sig)
{
NetNet*zero_net = new NetNet(scope, scope->local_symbol(),
NetNet::WIRE, sig->vector_width());
zero_net->data_type(sig->data_type());
zero_net->local_flag(true);
if (sig->data_type() == IVL_VT_REAL) {
verireal zero (val);
NetLiteral*zero_obj = new NetLiteral(scope, scope->local_symbol(), zero);
des->add_node(zero_obj);
connect(zero_net->pin(0), zero_obj->pin(0));
} else {
verinum zero ((int64_t)val);
zero = pad_to_width(zero, sig->vector_width());
NetConst*zero_obj = new NetConst(scope, scope->local_symbol(), zero);
des->add_node(zero_obj);
connect(zero_net->pin(0), zero_obj->pin(0));
}
NetAddSub*adder = new NetAddSub(scope, scope->local_symbol(), sig->vector_width());
des->add_node(adder);
adder->attribute(perm_string::literal("LPM_Direction"), verinum("SUB"));
connect(zero_net->pin(0), adder->pin_DataA());
connect(adder->pin_DataB(), sig->pin(0));
NetNet*tmp = new NetNet(scope, scope->local_symbol(),
NetNet::WIRE, sig->vector_width());
tmp->data_type(sig->data_type());
tmp->local_flag(true);
connect(adder->pin_Result(), tmp->pin(0));
return tmp;
}
NetNet* cast_to_int(Design*des, NetScope*scope, NetNet*src, unsigned wid)
{
if (src->data_type() != IVL_VT_REAL)
return src;
NetNet*tmp = new NetNet(scope, scope->local_symbol(), NetNet::WIRE, wid);
tmp->data_type(IVL_VT_LOGIC);
tmp->set_line(*src);
tmp->local_flag(true);
NetCastInt*cast = new NetCastInt(scope, scope->local_symbol(), wid);
cast->set_line(*src);
des->add_node(cast);
connect(cast->pin(0), tmp->pin(0));
connect(cast->pin(1), src->pin(0));
return tmp;
}
NetNet* cast_to_real(Design*des, NetScope*scope, NetNet*src)
{
if (src->data_type() == IVL_VT_REAL)
return src;
NetNet*tmp = new NetNet(scope, scope->local_symbol(), NetNet::WIRE);
tmp->data_type(IVL_VT_REAL);
tmp->set_line(*src);
tmp->local_flag(true);
NetCastReal*cast = new NetCastReal(scope, scope->local_symbol(), src->get_signed());
cast->set_line(*src);
des->add_node(cast);
connect(cast->pin(0), tmp->pin(0));
connect(cast->pin(1), src->pin(0));
return tmp;
}
/*
* Add a signed constant to an existing expression. Generate a new
* NetEBAdd node that has the input expression and an expression made
* from the constant value.
*/
static NetExpr* make_add_expr(NetExpr*expr, long val)
{
if (val == 0)
return expr;
// If the value to be added is <0, then instead generate a
// SUBTRACT node and turn the value positive.
char add_op = '+';
if (val < 0) {
add_op = '-';
val = -val;
}
verinum val_v (val);
val_v.has_sign(true);
if (expr->has_width()) {
val_v = verinum(val_v, expr->expr_width());
}
NetEConst*val_c = new NetEConst(val_v);
val_c->set_line(*expr);
NetEBAdd*res = new NetEBAdd(add_op, expr, val_c);
res->set_line(*expr);
return res;
}
/*
* Subtract an existing expression from a signed constant.
*/
static NetExpr* make_sub_expr(long val, NetExpr*expr)
{
verinum val_v (val, expr->expr_width());
val_v.has_sign(true);
NetEConst*val_c = new NetEConst(val_v);
val_c->set_line(*expr);
NetEBAdd*res = new NetEBAdd('-', val_c, expr);
res->set_line(*expr);
return res;
}
/*
* This routine is used to calculate the number of bits needed to
* contain the given number.
*/
static unsigned num_bits(long arg)
{
unsigned res = 0;
/* For a negative value we have room for one extra value, but
* we have a signed result so we need an extra bit for this. */
if (arg < 0) {
arg = -arg - 1;
res += 1;
}
/* Calculate the number of bits needed here. */
while (arg) {
res += 1;
arg >>= 1;
}
return res;
}
/*
* This routine generates the normalization expression needed for a variable
* bit select or a variable base expression for an indexed part select.
*/
NetExpr *normalize_variable_base(NetExpr *base, long msb, long lsb,
unsigned long wid, bool is_up)
{
long offset = lsb;
if (msb < lsb) {
/* Correct the offset if needed. */
if (is_up) offset -= wid - 1;
/* Calculate the space needed for the offset. */
unsigned min_wid = num_bits(offset);
/* We need enough space for the larger of the offset or the
* base expression. */
if (min_wid < base->expr_width()) min_wid = base->expr_width();
/* Now that we have the minimum needed width increase it by
* one to make room for the normalization calculation. */
min_wid += 1;
/* V0.9 does not handle small signed vectors correctly so
* increase the vector size to make this work. */
if (base->has_sign() && min_wid < 8*sizeof(int)) {
min_wid = 8*sizeof(int);
}
/* Pad the base expression to the correct width. */
base = pad_to_width(base, min_wid, *base);
/* If the base expression is unsigned and either the lsb
* is negative or it does not fill the width of the base
* expression then we could generate negative normalized
* values so cast the expression to signed to get the
* math correct. */
if ((lsb < 0 || num_bits(lsb+1) <= base->expr_width()) &&
! base->has_sign()) {
/* V0.9 does not handle small signed vectors correctly
* so increase the vector size to make this work. */
if (min_wid < 8*sizeof(int)) {
min_wid = 8*sizeof(int);
base = pad_to_width(base, min_wid, *base);
}
/* We need this extra select to hide the signed
* property from the padding above. It will be
* removed automatically during code generation. */
NetESelect *tmp = new NetESelect(base, 0 , min_wid);
tmp->set_line(*base);
tmp->cast_signed(true);
base = tmp;
}
/* Normalize the expression. */
base = make_sub_expr(offset, base);
} else {
/* Correct the offset if needed. */
if (!is_up) offset += wid - 1;
/* If the offset is zero then just return the base (index)
* expression. */
if (offset == 0) return base;
/* Calculate the space needed for the offset. */
unsigned min_wid = num_bits(-offset);
/* We need enough space for the larger of the offset or the
* base expression. */
if (min_wid < base->expr_width()) min_wid = base->expr_width();
/* Now that we have the minimum needed width increase it by
* one to make room for the normalization calculation. */
min_wid += 1;
/* V0.9 does not handle small signed vectors correctly so
* increase the vector size to make this work. */
if (base->has_sign() && min_wid < 8*sizeof(int)) {
min_wid = 8*sizeof(int);
}
/* Pad the base expression to the correct width. */
base = pad_to_width(base, min_wid, *base);
/* If the offset is greater than zero then we need to do
* signed math to get the location value correct. */
if (offset > 0 && ! base->has_sign()) {
/* V0.9 does not handle small signed vectors correctly
* so increase the vector size to make this work. */
if (min_wid < 8*sizeof(int)) {
min_wid = 8*sizeof(int);
base = pad_to_width(base, min_wid, *base);
}
/* We need this extra select to hide the signed
* property from the padding above. It will be
* removed automatically during code generation. */
NetESelect *tmp = new NetESelect(base, 0 , min_wid);
tmp->set_line(*base);
tmp->cast_signed(true);
base = tmp;
}
/* Normalize the expression. */
base = make_add_expr(base, -offset);
}
return base;
}
/*
* This routine generates the normalization expression needed for a variable
* array word select.
*/
NetExpr *normalize_variable_array_base(NetExpr *base, long offset,
unsigned count)
{
assert(offset != 0);
/* Calculate the space needed for the offset. */
unsigned min_wid = num_bits(-offset);
/* We need enough space for the larger of the offset or the base
* expression. */
if (min_wid < base->expr_width()) min_wid = base->expr_width();
/* Now that we have the minimum needed width increase it by one
* to make room for the normalization calculation. */
min_wid += 1;
/* Pad the base expression to the correct width. */
base = pad_to_width(base, min_wid, *base);
/* If the offset is greater than zero then we need to do signed
* math to get the location value correct. */
if (offset > 0 && ! base->has_sign()) {
/* V0.9 does not handle small signed vectors correctly
* so increase the vector size to make this work. */
if (min_wid < 8*sizeof(int)) {
min_wid = 8*sizeof(int);
base = pad_to_width(base, min_wid, *base);
}
/* We need this extra select to hide the signed property
* from the padding above. It will be removed automatically
* during code generation. */
NetESelect *tmp = new NetESelect(base, 0 , min_wid);
tmp->set_line(*base);
tmp->cast_signed(true);
base = tmp;
}
/* Normalize the expression. */
base = make_add_expr(base, -offset);
/* We should not need to do this, but .array/port does not
* handle a small signed index correctly and it is a major
* effort to fix it. For now we will just pad the expression
* enough so that any negative value when converted to
* unsigned is larger than the maximum array word. */
if (base->has_sign()) {
unsigned range_wid = num_bits(count-1) + 1;
if (min_wid < range_wid) {
base = pad_to_width(base, range_wid, *base);
}
}
return base;
}
NetEConst* make_const_x(unsigned long wid)
{
verinum xxx (verinum::Vx, wid);
NetEConst*resx = new NetEConst(xxx);
return resx;
}
NetEConst* make_const_0(unsigned long wid)
{
verinum xxx (verinum::V0, wid);
NetEConst*resx = new NetEConst(xxx);
return resx;
}
NetNet* make_const_x(Design*des, NetScope*scope, unsigned long wid)
{
verinum xxx (verinum::Vx, wid);
NetConst*res = new NetConst(scope, scope->local_symbol(), xxx);
des->add_node(res);
NetNet*sig = new NetNet(scope, scope->local_symbol(), NetNet::WIRE, wid);
sig->local_flag(true);
sig->data_type(IVL_VT_LOGIC);
connect(sig->pin(0), res->pin(0));
return sig;
}
NetExpr* condition_reduce(NetExpr*expr)
{
if (expr->expr_type() == IVL_VT_REAL) {
if (NetECReal *tmp = dynamic_cast<NetECReal*>(expr)) {
verinum::V res;
if (tmp->value().as_double() == 0.0) res = verinum::V0;
else res = verinum::V1;
verinum vres (res, 1, true);
NetExpr *rtn = new NetEConst(vres);
rtn->set_line(*expr);
delete expr;
return rtn;
}
NetExpr *rtn = new NetEBComp('n', expr,
new NetECReal(verireal(0.0)));
rtn->set_line(*expr);
return rtn;
}
if (expr->expr_width() == 1)
return expr;
verinum zero (verinum::V0, expr->expr_width());
NetEConst*ezero = new NetEConst(zero);
ezero->cast_signed(expr->has_sign());
ezero->set_line(*expr);
ezero->set_width(expr->expr_width());
NetEBComp*cmp = new NetEBComp('n', expr, ezero);
cmp->cast_signed(false);
cmp->set_line(*expr);
return cmp;
}
void probe_expr_width(Design*des, NetScope*scope, PExpr*pe)
{
ivl_variable_type_t expr_type = IVL_VT_NO_TYPE;
bool flag = false;
pe->test_width(des, scope, 0, 0, expr_type, flag);
}
NetExpr* elab_and_eval(Design*des, NetScope*scope,
const PExpr*pe, int expr_wid, int prune_width)
{
NetExpr*tmp = pe->elaborate_expr(des, scope, expr_wid, false);
if (tmp == 0) return 0;
eval_expr(tmp, prune_width);
return tmp;
}
void eval_expr(NetExpr*&expr, int prune_width)
{
assert(expr);
if (dynamic_cast<NetECReal*>(expr)) return;
/* Resize a constant if allowed and needed. */
if (NetEConst *tmp = dynamic_cast<NetEConst*>(expr)) {
if (prune_width <= 0) return;
if (tmp->has_width()) return;
if ((unsigned)prune_width <= tmp->expr_width()) return;
expr = pad_to_width(expr, (unsigned)prune_width, *expr);
return;
}
NetExpr*tmp = expr->eval_tree(prune_width);
if (tmp != 0) {
tmp->set_line(*expr);
delete expr;
expr = tmp;
}
}
bool eval_as_long(long&value, NetExpr*expr)
{
if (NetEConst*tmp = dynamic_cast<NetEConst*>(expr) ) {
value = tmp->value().as_long();
return true;
}
if (NetECReal*rtmp = dynamic_cast<NetECReal*>(expr)) {
value = rtmp->value().as_long();
return true;
}
return false;
}
bool eval_as_double(double&value, NetExpr*expr)
{
if (NetEConst*tmp = dynamic_cast<NetEConst*>(expr) ) {
value = tmp->value().as_double();
return true;
}
if (NetECReal*rtmp = dynamic_cast<NetECReal*>(expr)) {
value = rtmp->value().as_double();
return true;
}
return false;
}
/*
* At the parser level, a name component is a name with a collection
* of expressions. For example foo[N] is the name "foo" and the index
* expression "N". This function takes as input the name component and
* returns the path component name. It will evaluate the index
* expression if it is present.
*/
hname_t eval_path_component(Design*des, NetScope*scope,
const name_component_t&comp)
{
// No index expression, so the path component is an undecorated
// name, for example "foo".
if (comp.index.empty())
return hname_t(comp.name);
// The parser will assure that path components will have only
// one index. For example, foo[N] is one index, foo[n][m] is two.
assert(comp.index.size() == 1);
const index_component_t&index = comp.index.front();
if (index.sel != index_component_t::SEL_BIT) {
cerr << index.msb->get_fileline() << ": error: "
<< "Part select is not valid for this kind of object." << endl;
des->errors += 1;
return hname_t(comp.name, 0);
}
// The parser will assure that path components will have only
// bit select index expressions. For example, "foo[n]" is OK,
// but "foo[n:m]" is not.
assert(index.sel == index_component_t::SEL_BIT);
// Evaluate the bit select to get a number.
NetExpr*tmp = elab_and_eval(des, scope, index.msb, -1);
ivl_assert(*index.msb, tmp);
// Now we should have a constant value for the bit select
// expression, and we can use it to make the final hname_t
// value, for example "foo[5]".
if (NetEConst*ctmp = dynamic_cast<NetEConst*>(tmp)) {
hname_t res(comp.name, ctmp->value().as_long());
delete ctmp;
return res;
}
// Darn, the expression doesn't evaluate to a constant. That's
// an error to be reported. And make up a fake index value to
// return to the caller.
cerr << index.msb->get_fileline() << ": error: "
<< "Scope index expression is not constant: "
<< *index.msb << endl;
des->errors += 1;
delete tmp;
return hname_t (comp.name, 0);
}
std::list<hname_t> eval_scope_path(Design*des, NetScope*scope,
const pform_name_t&path)
{
list<hname_t> res;
typedef pform_name_t::const_iterator pform_path_it;
for (pform_path_it cur = path.begin() ; cur != path.end(); cur++) {
const name_component_t&comp = *cur;
res.push_back( eval_path_component(des,scope,comp) );
}
return res;
}
/*
* Human readable version of op. Used in elaboration error messages.
*/
const char *human_readable_op(const char op, bool unary)
{
const char *type;
switch (op) {
case '~': type = "~"; break; // Negation
case '+': type = "+"; break;
case '-': type = "-"; break;
case '*': type = "*"; break;
case '/': type = "/"; break;
case '%': type = "%"; break;
case '<': type = "<"; break;
case '>': type = ">"; break;
case 'L': type = "<="; break;
case 'G': type = ">="; break;
case '^': type = "^"; break; // XOR
case 'X': type = "~^"; break; // XNOR
case '&': type = "&"; break; // Bitwise AND
case 'A': type = "~&"; break; // NAND (~&)
case '|': type = "|"; break; // Bitwise OR
case 'O': type = "~|"; break; // NOR
case '!': type = "!"; break; // Logical NOT
case 'a': type = "&&"; break; // Logical AND
case 'o': type = "||"; break; // Logical OR
case 'e': type = "=="; break;
case 'n': type = "!="; break;
case 'E': type = "==="; break; // Case equality
case 'N':
if (unary) type = "~|"; // NOR
else type = "!=="; // Case inequality
break;
case 'l': type = "<<(<)"; break; // Left shifts
case 'r': type = ">>"; break; // Logical right shift
case 'R': type = ">>>"; break; // Arithmetic right shift
case 'p': type = "**"; break; // Power
default:
type = "???";
assert(0);
}
return type;
}
const_bool const_logical(const NetExpr*expr)
{
switch (expr->expr_type()) {
case IVL_VT_REAL: {
const NetECReal*val = dynamic_cast<const NetECReal*> (expr);
if (val == 0) return C_NON;
if (val->value().as_double() == 0.0) return C_0;
else return C_1;
}
case IVL_VT_BOOL:
case IVL_VT_LOGIC: {
const NetEConst*val = dynamic_cast<const NetEConst*> (expr);
if (val == 0) return C_NON;
verinum cval = val->value();
const_bool res = C_0;
for (unsigned idx = 0; idx < cval.len(); idx += 1) {
switch (cval.get(idx)) {
case verinum::V1:
res = C_1;
break;
case verinum::V0:
break;
default:
if (res == C_0) res = C_X;
break;
}
}
return res;
}
default:
break;
}
return C_NON;
}
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