Files
iverilog/PScope.cc
T
Lars-Peter Clausen 2e0d6d5af1 Allow to attach additional information to typedefs
Currently typedefs are just a pointer to a data_type_t.

Currently typedefs are implemented by setting the name field of a
data_type_t when a typedef of the type is declared. This works mostly, but
there are some corner cases that can't be supported.

E.g. a typedef of a typedef does not work as it overwrites the name field
of the same data_type_t multiple times.

Forward typedefs can also not be supported since forward typedefs allow to
reference a type before it has been declared.

There are also some problems with type identifier references from a
higher-level scope if there is a type identifier in the current scope with
the same name, but it is declared after the type identifier has been
referenced. E.g. in the following x should be a vector fo width 8, but it
will be a vector of width 4, because while the right type is used it is
elaborated in the wrong scope.

```
localparam A = 8;
typedef logic [A-1:0] T;
module M;
  localparam A = 4;
  T x;
  typedef int T;
endmodule
```

Furthermore typedefs used for the type of ports are elaborated in the wrong
scope.

To handle these corner case issues introduce a data_type_t for typedefs.

Signed-off-by: Lars-Peter Clausen <[email protected]>
2022-12-11 10:18:22 -08:00

69 lines
1.8 KiB
C++

/*
* Copyright (c) 2008-2021 Stephen Williams ([email protected])
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
# include "PScope.h"
using namespace std;
bool LexicalScope::var_init_needs_explicit_lifetime() const
{
return false;
}
PWire* LexicalScope::wires_find(perm_string name)
{
map<perm_string,PWire*>::const_iterator cur = wires.find(name);
if (cur == wires.end())
return 0;
else
return (*cur).second;
}
PNamedItem::SymbolType LexicalScope::param_expr_t::symbol_type() const
{
return PARAM;
}
PScope::PScope(perm_string n, LexicalScope*parent)
: LexicalScope(parent), name_(n)
{
time_unit = 0;
time_precision = 0;
time_unit_is_default = true;
time_prec_is_default = true;
}
PScope::~PScope()
{
for(typedef_map_t::iterator it = typedefs.begin(); it != typedefs.end();
++it)
delete it->second;
}
PScopeExtra::PScopeExtra(perm_string n, LexicalScope*parent)
: PScope(n, parent)
{
time_unit_is_local = false;
time_prec_is_local = false;
}
PScopeExtra::~PScopeExtra()
{
}