caiyu/nextpnr
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

frontend: Draft for a generic template-based frontend API

Browse Source 
Signed-off-by: David Shah <dave@ds0.me>
This commit is contained in:
David Shah 2019-11-11 16:55:52 +00:00
parent b6e2159cec
commit fa7317f594
1 changed files with 102 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

102
frontend/generic.h Normal file
View File

@ -0,0 +1,102 @@
/*
* nextpnr -- Next Generation Place and Route
*
* Copyright (C) 2019 David Shah <dave@ds0.me>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
/*
* Generic Frontend Framework
*
* This is designed to make it possible to build frontends for parsing any format isomorphic to Yosys JSON [1]
* with maximal inlining and minimal need for overhead such as runtime polymorphism or extra wrapper types.
*
* [1] http://www.clifford.at/yosys/cmd_write_json.html
*
* The frontend should implement a class referred to as FrontendType that defines the following type(def)s and
* functions:
*
* Types:
* ModuleDataType: corresponds to a single entry in "modules"
* ModulePortDataType: corresponds to a single entry in "ports" of a module
* CellDataType: corresponds to a single entry in "cells"
* NetnameDataType: corresponds to a single entry in "netnames"
* BitVectorDataType: corresponds to a signal/constant bit vector (e.g. a "connections" field)
*
* Functions:
*
* void foreach_module(Func);
* calls Func(const std::string &name, const ModuleDataType &mod);
* for each module in the netlist
*
* void foreach_port(const ModuleDataType &mod, Func);
* calls Func(const std::string &name, const ModulePortDataType &port);
* for each port of mod
*
* void foreach_cell(const ModuleDataType &mod, Func);
* calls Func(const std::string &name, const CellDataType &cell);
* for each cell of mod
*
* void foreach_netname(const ModuleDataType &mod, Func);
* calls Func(const std::string &name, const NetnameDataType &cell);
* for each netname entry of mod
*
* PortType get_port_dir(const ModulePortDataType &port);
* gets the PortType direction of a module port
*
* int get_port_offset(const ModulePortDataType &port);
* gets the start bit number of a port
*
* bool is_port_upto(const ModulePortDataType &port);
* returns true if a port is an "upto" type port
*
* const BitVectorDataType &get_port_bits(const ModulePortDataType &port);
* gets the bit vector of a module port
*
* const std::string& get_cell_type(const CellDataType &cell);
* gets the type of a cell
*
* void foreach_attr(const {ModuleDataType|CellDataType|ModulePortDataType|NetnameDataType} &obj, Func);
* calls Func(const std::string &name, const Property &value);
* for each attribute on a module, cell, module port or net
*
* void foreach_param(const CellDataType &obj, Func);
* calls Func(const std::string &name, const Property &value);
* for each parameter of a cell
*
* void foreach_port_dir(const CellDataType &cell, Func);
* calls Func(const std::string &name, PortType dir);
* for each port direction of a cell
*
* void foreach_port_conn(const CellDataType &cell, Func);
* calls Func(const std::string &name, const BitVectorDataType &conn);
* for each port connection of a cell
*
* const BitVectorDataType &get_net_bits(const NetnameDataType &net);
* gets the BitVector corresponding to the bits entry of a netname field
*
* int get_vector_length(const BitVectorDataType &bits);
* gets the length of a BitVector
*
* bool is_vector_bit_constant(const BitVectorDataType &bits, int i);
* returns true if bit <i> of bits is constant
*
* char get_vector_bit_constval(const BitVectorDataType &bits, int i);
* returns a char [01xz] corresponding to the constant value of bit <i>
*
* int get_vector_bit_signal(const BitVectorDataType &bits, int i);
* returns the signal number of vector bit <i>
*
*/