yosys/backends/functional/cxx.cc

458 lines
17 KiB
C++

/*
* yosys -- Yosys Open SYnthesis Suite
*
* Copyright (C) 2024 Emily Schmidt <emily@yosyshq.com>
*
* 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.
*
*/
#include "kernel/yosys.h"
#include "kernel/drivertools.h"
#include "kernel/topo_scc.h"
#include "kernel/functional.h"
#include "kernel/graphtools.h"
USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN
const char *reserved_keywords[] = {
"alignas","alignof","and","and_eq","asm","atomic_cancel","atomic_commit",
"atomic_noexcept","auto","bitand","bitor","bool","break","case",
"catch","char","char16_t","char32_t","char8_t","class","co_await",
"co_return","co_yield","compl","concept","const","const_cast","consteval",
"constexpr","constinit","continue","decltype","default","delete",
"do","double","dynamic_cast","else","enum","explicit","export",
"extern","false","float","for","friend","goto","if","inline",
"int","long","mutable","namespace","new","noexcept","not","not_eq",
"nullptr","operator","or","or_eq","private","protected","public",
"reflexpr","register","reinterpret_cast","requires","return","short",
"signed","sizeof","static","static_log_assert","static_cast","struct",
"switch","synchronized","template","this","thread_local","throw",
"true","try","typedef","typeid","typename","union","unsigned",
"using","virtual","void","volatile","wchar_t","while","xor","xor_eq",
nullptr
};
struct CxxScope {
pool<std::string> used_names;
dict<IdString, std::string> name_map;
CxxScope() {
for(const char **p = reserved_keywords; *p != nullptr; p++)
reserve(*p);
}
void reserve(std::string name) {
used_names.insert(name);
}
std::string insert(IdString id) {
std::string str = RTLIL::unescape_id(id);
for(size_t i = 0; i < str.size(); i++)
if(strchr("!\"#%&'()*+,-./:;<=>?@[]\\^`{|}~ ", str[i]))
str[i] = '_';
if(used_names.count(str) == 0){
used_names.insert(str);
name_map.insert({id, str});
return str;
}
for (int idx = 0 ; ; idx++){
std::string suffixed = str + "_" + std::to_string(idx);
if (used_names.count(suffixed) == 0) {
used_names.insert(suffixed);
if(name_map.count(id) == 0)
name_map.insert({id, suffixed});
return suffixed;
}
}
}
std::string operator[](IdString id) {
if(name_map.count(id) > 0)
return name_map[id];
else
return insert(id);
}
};
struct CxxWriter {
std::ostream &f;
CxxWriter(std::ostream &out) : f(out) {}
void printf(const char *fmt, ...)
{
va_list va;
va_start(va, fmt);
f << vstringf(fmt, va);
va_end(va);
}
};
struct CxxStruct {
std::string name;
dict<IdString, std::string> types;
CxxScope scope;
bool generate_methods;
int count;
CxxStruct(std::string name, bool generate_methods = false, int count = 0)
: name(name), generate_methods(generate_methods), count(count) {
scope.reserve("out");
scope.reserve("dump");
}
void insert(IdString name, std::string type) {
scope.insert(name);
types.insert({name, type});
}
void print(CxxWriter &f) {
f.printf("struct %s {\n", name.c_str());
for (auto p : types) {
f.printf("\t%s %s;\n", p.second.c_str(), scope[p.first].c_str());
}
f.printf("\n\ttemplate <typename T> void dump(T &out) const {\n");
for (auto p : types) {
f.printf("\t\tout(\"%s\", %s);\n", RTLIL::unescape_id(p.first).c_str(), scope[p.first].c_str());
}
f.printf("\t}\n\n");
if (generate_methods) {
// Add size method
f.printf("\tint size() const {\n");
f.printf("\t\treturn %d;\n", count);
f.printf("\t}\n\n");
// Add get_input method
f.printf("\tstd::variant<%s> get_input(const int index) {\n", generate_variant_types().c_str());
f.printf("\t\tswitch (index) {\n");
int idx = 0;
for (auto p : types) {
f.printf("\t\t\tcase %d: return std::ref(%s);\n", idx, scope[p.first].c_str());
idx++;
}
f.printf("\t\t\tdefault: throw std::out_of_range(\"Invalid input index\");\n");
f.printf("\t\t}\n");
f.printf("\t}\n");
}
f.printf("};\n\n");
};
std::string operator[](IdString field) {
return scope[field];
}
private:
std::string generate_variant_types() const {
std::set<std::string> unique_types;
for (const auto& p : types) {
unique_types.insert("std::reference_wrapper<" + p.second + ">");
}
std::ostringstream oss;
for (auto it = unique_types.begin(); it != unique_types.end(); ++it) {
if (it != unique_types.begin()) {
oss << ", ";
}
oss << *it;
}
return oss.str();
}
};
struct CxxFunction {
IdString name;
int width;
dict<IdString, Const> parameters;
CxxFunction(IdString name, int width) : name(name), width(width) {}
CxxFunction(IdString name, int width, dict<IdString, Const> parameters) : name(name), width(width), parameters(parameters) {}
bool operator==(CxxFunction const &other) const {
return name == other.name && parameters == other.parameters && width == other.width;
}
unsigned int hash() const {
return mkhash(name.hash(), parameters.hash());
}
};
typedef ComputeGraph<CxxFunction, int, IdString, IdString> CxxComputeGraph;
class CxxComputeGraphFactory {
CxxComputeGraph &graph;
using T = CxxComputeGraph::Ref;
static bool is_single_output(IdString type)
{
auto it = yosys_celltypes.cell_types.find(type);
return it != yosys_celltypes.cell_types.end() && it->second.outputs.size() <= 1;
}
public:
CxxComputeGraphFactory(CxxComputeGraph &g) : graph(g) {}
T slice(T a, int in_width, int offset, int out_width) {
log_assert(offset + out_width <= in_width);
return graph.add(CxxFunction(ID($$slice), out_width, {{ID(offset), offset}}), 0, std::array<T, 1>{a});
}
T extend(T a, int in_width, int out_width, bool is_signed) {
log_assert(in_width < out_width);
if(is_signed)
return graph.add(CxxFunction(ID($sign_extend), out_width, {{ID(WIDTH), out_width}}), 0, std::array<T, 1>{a});
else
return graph.add(CxxFunction(ID($zero_extend), out_width, {{ID(WIDTH), out_width}}), 0, std::array<T, 1>{a});
}
T concat(T a, int a_width, T b, int b_width) {
return graph.add(CxxFunction(ID($$concat), a_width + b_width), 0, std::array<T, 2>{a, b});
}
T add(T a, T b, int width) { return graph.add(CxxFunction(ID($add), width), 0, std::array<T, 2>{a, b}); }
T sub(T a, T b, int width) { return graph.add(CxxFunction(ID($sub), width), 0, std::array<T, 2>{a, b}); }
T bitwise_and(T a, T b, int width) { return graph.add(CxxFunction(ID($and), width), 0, std::array<T, 2>{a, b}); }
T bitwise_or(T a, T b, int width) { return graph.add(CxxFunction(ID($or), width), 0, std::array<T, 2>{a, b}); }
T bitwise_xor(T a, T b, int width) { return graph.add(CxxFunction(ID($xor), width), 0, std::array<T, 2>{a, b}); }
T bitwise_not(T a, int width) { return graph.add(CxxFunction(ID($not), width), 0, std::array<T, 1>{a}); }
T neg(T a, int width) { return graph.add(CxxFunction(ID($neg), width), 0, std::array<T, 1>{a}); }
T mux(T a, T b, T s, int width) { return graph.add(CxxFunction(ID($mux), width), 0, std::array<T, 3>{a, b, s}); }
T pmux(T a, T b, T s, int width, int) { return graph.add(CxxFunction(ID($pmux), width), 0, std::array<T, 3>{a, b, s}); }
T reduce_and(T a, int) { return graph.add(CxxFunction(ID($reduce_and), 1), 0, std::array<T, 1>{a}); }
T reduce_or(T a, int) { return graph.add(CxxFunction(ID($reduce_or), 1), 0, std::array<T, 1>{a}); }
T reduce_xor(T a, int) { return graph.add(CxxFunction(ID($reduce_xor), 1), 0, std::array<T, 1>{a}); }
T eq(T a, T b, int) { return graph.add(CxxFunction(ID($eq), 1), 0, std::array<T, 2>{a, b}); }
T ne(T a, T b, int) { return graph.add(CxxFunction(ID($ne), 1), 0, std::array<T, 2>{a, b}); }
T gt(T a, T b, int) { return graph.add(CxxFunction(ID($gt), 1), 0, std::array<T, 2>{a, b}); }
T ge(T a, T b, int) { return graph.add(CxxFunction(ID($ge), 1), 0, std::array<T, 2>{a, b}); }
T ugt(T a, T b, int) { return graph.add(CxxFunction(ID($ugt), 1), 0, std::array<T, 2>{a, b}); }
T uge(T a, T b, int) { return graph.add(CxxFunction(ID($uge), 1), 0, std::array<T, 2>{a, b}); }
T logical_shift_left(T a, T b, int y_width, int) { return graph.add(CxxFunction(ID($shl), y_width, {{ID(WIDTH), y_width}}), 0, std::array<T, 2>{a, b}); }
T logical_shift_right(T a, T b, int y_width, int) { return graph.add(CxxFunction(ID($shr), y_width, {{ID(WIDTH), y_width}}), 0, std::array<T, 2>{a, b}); }
T arithmetic_shift_right(T a, T b, int y_width, int) { return graph.add(CxxFunction(ID($asr), y_width, {{ID(WIDTH), y_width}}), 0, std::array<T, 2>{a, b}); }
T constant(RTLIL::Const value) {
return graph.add(CxxFunction(ID($$const), value.size(), {{ID(value), value}}), 0);
}
T input(IdString name, int width) { return graph.add(CxxFunction(ID($$input), width, {{name, {}}}), 0); }
T state(IdString name, int width) { return graph.add(CxxFunction(ID($$state), width, {{name, {}}}), 0); }
T cell_output(T cell, IdString type, IdString name, int width) {
if (is_single_output(type))
return cell;
else
return graph.add(CxxFunction(ID($$cell_output), width, {{name, {}}}), 0, std::array<T, 1>{cell});
}
T multiple(vector<T> args, int width) {
return graph.add(CxxFunction(ID($$multiple), width), 0, args);
}
T undriven(int width) {
return graph.add(CxxFunction(ID($$undriven), width), 0);
}
T create_pending(int width) {
return graph.add(CxxFunction(ID($$pending), width), 0);
}
void update_pending(T pending, T node) {
log_assert(pending.function().name == ID($$pending));
pending.set_function(CxxFunction(ID($$buf), pending.function().width));
pending.append_arg(node);
}
void declare_output(T node, IdString name, int) {
node.assign_key(name);
}
void declare_state(T node, IdString name, int) {
node.assign_key(name);
}
void suggest_name(T node, IdString name) {
node.sparse_attr() = name;
}
};
struct FunctionalCxxBackend : public Backend
{
FunctionalCxxBackend() : Backend("functional_cxx", "convert design to C++ using the functional backend") {}
void help() override
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
}
CxxComputeGraph calculate_compute_graph(RTLIL::Module *module)
{
CxxComputeGraph compute_graph;
CxxComputeGraphFactory factory(compute_graph);
ComputeGraphConstruction<CxxComputeGraph::Ref, CxxComputeGraphFactory> construction(factory);
construction.add_module(module);
construction.process_queue();
// Perform topo sort and detect SCCs
CxxComputeGraph::SccAdaptor compute_graph_scc(compute_graph);
bool scc = false;
std::vector<int> perm;
topo_sorted_sccs(compute_graph_scc, [&](int *begin, int *end) {
perm.insert(perm.end(), begin, end);
if (end > begin + 1)
{
log_warning("SCC:");
for (int *i = begin; i != end; ++i)
log(" %d(%s)(%s)", *i, compute_graph[*i].function().name.c_str(), compute_graph[*i].has_sparse_attr() ? compute_graph[*i].sparse_attr().c_str() : "");
log("\n");
scc = true;
}
}, /* sources_first */ true);
compute_graph.permute(perm);
if(scc) log_error("combinational loops, aborting\n");
// Forward $$buf
std::vector<int> alias;
perm.clear();
for (int i = 0; i < compute_graph.size(); ++i)
{
auto node = compute_graph[i];
if (node.function().name == ID($$buf) && node.arg(0).index() < i)
{
int target_index = alias[node.arg(0).index()];
auto target_node = compute_graph[perm[target_index]];
if(!target_node.has_sparse_attr() && node.has_sparse_attr())
target_node.sparse_attr() = node.sparse_attr();
alias.push_back(target_index);
}
else
{
alias.push_back(GetSize(perm));
perm.push_back(i);
}
}
compute_graph.permute(perm, alias);
return compute_graph;
}
void printCxx(std::ostream &stream, std::string, std::string const & name, CxxComputeGraph &compute_graph)
{
dict<IdString, int> inputs, state;
CxxWriter f(stream);
// Dump the compute graph
for (int i = 0; i < compute_graph.size(); ++i)
{
auto ref = compute_graph[i];
if(ref.function().name == ID($$input))
inputs[ref.function().parameters.begin()->first] = ref.function().width;
if(ref.function().name == ID($$state))
state[ref.function().parameters.begin()->first] = ref.function().width;
}
f.printf("#include \"sim.h\"\n");
f.printf("#include <variant>\n");
CxxStruct input_struct(name + "_Inputs", true, inputs.size());
for (auto const &input : inputs)
input_struct.insert(input.first, "Signal<" + std::to_string(input.second) + ">");
CxxStruct output_struct(name + "_Outputs");
for (auto const &key : compute_graph.keys())
if(state.count(key.first) == 0)
output_struct.insert(key.first, "Signal<" + std::to_string(compute_graph[key.second].function().width) + ">");
CxxStruct state_struct(name + "_State");
for (auto const &state_var : state)
state_struct.insert(state_var.first, "Signal<" + std::to_string(state_var.second) + ">");
idict<std::string> node_names;
CxxScope locals;
input_struct.print(f);
output_struct.print(f);
state_struct.print(f);
f.printf("void %s(%s_Inputs const &input, %s_Outputs &output, %s_State const &current_state, %s_State &next_state)\n{\n", name.c_str(), name.c_str(), name.c_str(), name.c_str(), name.c_str());
locals.reserve("input");
locals.reserve("output");
locals.reserve("current_state");
locals.reserve("next_state");
for (int i = 0; i < compute_graph.size(); ++i)
{
auto ref = compute_graph[i];
int width = ref.function().width;
std::string name;
if(ref.has_sparse_attr())
name = locals.insert(ref.sparse_attr());
else
name = locals.insert("\\n" + std::to_string(i));
node_names(name);
if(ref.function().name == ID($$input))
f.printf("\tSignal<%d> %s = input.%s;\n", width, name.c_str(), input_struct[ref.function().parameters.begin()->first].c_str());
else if(ref.function().name == ID($$state))
f.printf("\tSignal<%d> %s = current_state.%s;\n", width, name.c_str(), state_struct[ref.function().parameters.begin()->first].c_str());
else if(ref.function().name == ID($$buf))
f.printf("\tSignal<%d> %s = %s;\n", width, name.c_str(), node_names[ref.arg(0).index()].c_str());
else if(ref.function().name == ID($$cell_output))
f.printf("\tSignal<%d> %s = %s.%s;\n", width, name.c_str(), node_names[ref.arg(0).index()].c_str(), RTLIL::unescape_id(ref.function().parameters.begin()->first).c_str());
else if(ref.function().name == ID($$const)){
auto c = ref.function().parameters.begin()->second;
if(c.size() <= 32){
f.printf("\tSignal<%d> %s = $const<%d>(%#x);\n", width, name.c_str(), width, (uint32_t) c.as_int());
}else{
f.printf("\tSignal<%d> %s = $const<%d>({%#x", width, name.c_str(), width, (uint32_t) c.as_int());
while(c.size() > 32){
c = c.extract(32, c.size() - 32);
f.printf(", %#x", c.as_int());
}
f.printf("});\n");
}
}else if(ref.function().name == ID($$undriven))
f.printf("\tSignal<%d> %s; //undriven\n", width, name.c_str());
else if(ref.function().name == ID($$slice))
f.printf("\tSignal<%d> %s = slice<%d>(%s, %d);\n", width, name.c_str(), width, node_names[ref.arg(0).index()].c_str(), ref.function().parameters.at(ID(offset)).as_int());
else if(ref.function().name == ID($$concat)){
f.printf("\tauto %s = concat(", name.c_str());
for (int i = 0, end = ref.size(); i != end; ++i){
if(i > 0)
f.printf(", ");
f.printf("%s", node_names[ref.arg(i).index()].c_str());
}
f.printf(");\n");
}else{
f.printf("\t");
if(ref.function().width > 0)
f.printf("Signal<%d>", ref.function().width);
else
f.printf("%s_Outputs", log_id(ref.function().name));
f.printf(" %s = %s", name.c_str(), log_id(ref.function().name));
if(ref.function().parameters.count(ID(WIDTH))){
f.printf("<%d>", ref.function().parameters.at(ID(WIDTH)).as_int());
}
f.printf("(");
for (int i = 0, end = ref.size(); i != end; ++i)
f.printf("%s%s", i>0?", ":"", node_names[ref.arg(i).index()].c_str());
f.printf("); //");
for (auto const &param : ref.function().parameters)
{
if (param.second.empty())
f.printf("[%s]", log_id(param.first));
else
f.printf("[%s=%s]", log_id(param.first), log_const(param.second));
}
f.printf("\n");
}
}
for (auto const &key : compute_graph.keys())
{
f.printf("\t%s.%s = %s;\n", state.count(key.first) > 0 ? "next_state" : "output", state_struct[key.first].c_str(), node_names[key.second].c_str());
}
f.printf("}\n");
}
void execute(std::ostream *&f, std::string filename, std::vector<std::string> args, RTLIL::Design *design) override
{
log_header(design, "Executing Functional C++ backend.\n");
size_t argidx = 1;
extra_args(f, filename, args, argidx, design);
for (auto module : design->selected_modules()) {
log("Dumping module `%s'.\n", module->name.c_str());
auto compute_graph = calculate_compute_graph(module);
printCxx(*f, filename, RTLIL::unescape_id(module->name), compute_graph);
}
}
} FunctionalCxxBackend;
PRIVATE_NAMESPACE_END