Major redesign of Verific SVA importer

Signed-off-by: Clifford Wolf <clifford@clifford.at>
This commit is contained in:
Clifford Wolf 2018-02-27 20:33:15 +01:00
parent 6f26695d9b
commit 25e33d7ab8
2 changed files with 574 additions and 6 deletions

View File

@ -24,7 +24,6 @@
// not prop
// prop or prop
// prop and prop
// seq |-> prop
// seq |=> prop
// if (expr) prop [else prop]
// prop until prop
@ -35,7 +34,6 @@
//
// seq:
// expr
// expr ##N seq
// expr ##[N:M] seq
// seq or seq
// seq and seq
@ -43,12 +41,24 @@
// first_match (seq)
// expr throughout seq
// seq within seq
// seq [*N]
// seq [*N:M]
// expr [=N]
// expr [=N:M]
// expr [->N]
// expr [->N:M]
//
// Notes:
// |=> is a placeholder for |-> and |=>
// "until" is a placeholder for all until operators
// ##[N:M], [*N:M], [=N:M], [->N:M] includes ##N, [*N], [=N], [->N]
//
// Currently supported property styles:
// not seq
// seq |=> seq
// seq |=> seq until seq
//
// Currently supported sequence operators:
// ##[N:M]
// [*N:M]
// throughout
#include "kernel/yosys.h"
@ -60,6 +70,316 @@ USING_YOSYS_NAMESPACE
using namespace Verific;
#endif
PRIVATE_NAMESPACE_BEGIN
struct SvaFsmNode
{
vector<pair<int, SigBit>> edges, links;
};
struct SvaFsm
{
Module *module;
SigBit clock;
bool clockpol;
SigBit trigger_sig = State::S1, disable_sig;
SigBit accept_sig = State::Sz, reject_sig = State::Sz;
SigBit throughout_sig = State::S1;
bool materialized = false;
vector<SigBit> disable_stack;
vector<SigBit> throughout_stack;
int startNode, acceptNode, rejectNode;
vector<SvaFsmNode> nodes;
SvaFsm(Module *mod, SigBit clk, bool clkpol, SigBit dis = State::S0, SigBit trig = State::S1)
{
module = mod;
clock = clk;
clockpol = clkpol;
disable_sig = dis;
trigger_sig = trig;
startNode = createNode();
acceptNode = createNode();
rejectNode = createNode();
}
void pushDisable(SigBit sig)
{
log_assert(!materialized);
disable_stack.push_back(disable_sig);
if (disable_sig == State::S0)
disable_sig = sig;
else
disable_sig = module->Or(NEW_ID, disable_sig, sig);
}
void popDisable()
{
log_assert(!materialized);
log_assert(!disable_stack.empty());
disable_sig = disable_stack.back();
disable_stack.pop_back();
}
void pushThroughout(SigBit sig)
{
log_assert(!materialized);
throughout_stack.push_back(throughout_sig);
if (throughout_sig == State::S1)
throughout_sig = sig;
else
throughout_sig = module->And(NEW_ID, throughout_sig, sig);
}
void popThroughout()
{
log_assert(!materialized);
log_assert(!throughout_stack.empty());
throughout_sig = throughout_stack.back();
throughout_stack.pop_back();
}
SigBit getAccept()
{
if (accept_sig != State::Sz)
return accept_sig;
log_assert(!materialized);
accept_sig = module->addWire(NEW_ID);
return accept_sig;
}
SigBit getReject()
{
if (reject_sig != State::Sz)
return reject_sig;
log_assert(!materialized);
reject_sig = module->addWire(NEW_ID);
return reject_sig;
}
int createNode()
{
log_assert(!materialized);
int idx = GetSize(nodes);
nodes.push_back(SvaFsmNode());
return idx;
}
void createEdge(int from_node, int to_node, SigBit ctrl = State::S1)
{
log_assert(!materialized);
log_assert(0 <= from_node && from_node < GetSize(nodes));
log_assert(0 <= to_node && to_node < GetSize(nodes));
if (throughout_sig != State::S1) {
if (ctrl != State::S1)
ctrl = module->And(NEW_ID, throughout_sig, ctrl);
else
ctrl = throughout_sig;
}
nodes[from_node].edges.push_back(make_pair(to_node, ctrl));
}
void createLink(int from_node, int to_node, SigBit ctrl = State::S1)
{
log_assert(!materialized);
log_assert(0 <= from_node && from_node < GetSize(nodes));
log_assert(0 <= to_node && to_node < GetSize(nodes));
if (throughout_sig != State::S1) {
if (ctrl != State::S1)
ctrl = module->And(NEW_ID, throughout_sig, ctrl);
else
ctrl = throughout_sig;
}
nodes[from_node].links.push_back(make_pair(to_node, ctrl));
}
void make_link_order(vector<int> &order, int node, int min)
{
order[node] = std::max(order[node], min);
for (auto &it : nodes[node].links)
make_link_order(order, it.first, order[node]+1);
}
void materialize_ndfsm()
{
log_assert(!materialized);
materialized = true;
vector<SigBit> next_state_sig(GetSize(nodes));
vector<SigBit> state_sig(GetSize(nodes));
// Create state FFs
{
SigBit not_disable = State::S1;
if (disable_sig != State::S0)
not_disable = module->Not(NEW_ID, disable_sig);
for (int i = 0; i < GetSize(nodes); i++)
{
next_state_sig[i] = module->addWire(NEW_ID);
Wire *w = module->addWire(NEW_ID);
w->attributes["\\init"] = Const(0, 1);
state_sig[i] = w;
module->addDff(NEW_ID, clock, next_state_sig[i], state_sig[i], clockpol);
if (i == startNode)
state_sig[i] = module->Or(NEW_ID, state_sig[i], trigger_sig);
if (disable_sig != State::S0)
state_sig[i] = module->And(NEW_ID, state_sig[i], not_disable);
}
}
// Follow Links
{
vector<int> node_order(GetSize(nodes));
vector<vector<int>> order_to_nodes;
for (int i = 0; i < GetSize(nodes); i++)
make_link_order(node_order, i, 0);
for (int i = 0; i < GetSize(nodes); i++) {
if (node_order[i] >= GetSize(order_to_nodes))
order_to_nodes.resize(node_order[i]+1);
order_to_nodes[node_order[i]].push_back(i);
}
for (int order = 0; order < GetSize(order_to_nodes); order++)
for (int node : order_to_nodes[order])
{
for (auto &it : nodes[node].links)
{
int target = it.first;
SigBit ctrl = state_sig[node];
if (it.second != State::S1)
ctrl = module->And(NEW_ID, ctrl, it.second);
state_sig[target] = module->Or(NEW_ID, state_sig[target], ctrl);
}
}
}
// Construct activations
{
vector<SigSpec> activate_sig(GetSize(nodes));
vector<SigBit> activate_bit(GetSize(nodes));
for (int i = 0; i < GetSize(nodes); i++) {
for (auto &it : nodes[i].edges)
activate_sig[it.first].append(module->And(NEW_ID, state_sig[i], it.second));
}
for (int i = 0; i < GetSize(nodes); i++) {
if (GetSize(activate_sig[i]) == 0)
activate_bit[i] = State::S0;
else if (GetSize(activate_sig[i]) == 1)
activate_bit[i] = activate_sig[i];
else
activate_bit[i] = module->ReduceOr(NEW_ID, activate_sig[i]);
}
if (activate_bit[rejectNode] != State::S0)
{
SigBit not_rej = module->Not(NEW_ID, next_state_sig[rejectNode]);
for (int i = 0; i < GetSize(nodes); i++)
if (i != rejectNode && activate_bit[i] != State::S0)
activate_bit[i] = module->And(NEW_ID, activate_bit[i], not_rej);
activate_bit[rejectNode] = State::S0;
}
for (int i = 0; i < GetSize(nodes); i++) {
module->connect(next_state_sig[i], activate_bit[i]);
}
}
// Construct output signals
if (accept_sig != State::Sz) {
module->connect(accept_sig, state_sig[acceptNode]);
}
if (reject_sig != State::Sz)
{
SigBit fsm_active = module->ReduceOr(NEW_ID, state_sig);
SigBit fsm_next_active = module->ReduceOr(NEW_ID, next_state_sig);
module->addEq(NEW_ID, {state_sig[acceptNode], fsm_next_active, fsm_active}, SigSpec(1, 3), reject_sig);
}
}
void materialize_dfsm()
{
// FIXME
log_abort();
}
bool is_linear()
{
for (int i = 0; i < GetSize(nodes); i++)
if (GetSize(nodes[i].edges) + GetSize(nodes[i].links) > 1)
return false;
return true;
}
void dump()
{
log("-----------\n");
for (int i = 0; i < GetSize(nodes); i++)
{
log("node %d:\n", i);
if (i == startNode)
log(" startNode\n");
if (i == rejectNode)
log(" rejectNode\n");
if (i == acceptNode)
log(" acceptNode\n");
for (auto &it : nodes[i].edges) {
if (it.second != State::S1)
log(" egde %s -> %d\n", log_signal(it.second), it.first);
else
log(" egde -> %d\n", it.first);
}
for (auto &it : nodes[i].links) {
if (it.second != State::S1)
log(" link %s -> %d\n", log_signal(it.second), it.first);
else
log(" link -> %d\n", it.first);
}
}
log("-----------\n");
}
};
PRIVATE_NAMESPACE_END
YOSYS_NAMESPACE_BEGIN
pool<int> verific_sva_prims = {
@ -254,6 +574,253 @@ struct VerificSvaImporter
// ----------------------------------------------------------
// SVA Importer
int parse_sequence(SvaFsm *fsm, int start_node, Net *net)
{
Instance *inst = net_to_ast_driver(net);
if (inst == nullptr) {
int node = fsm->createNode();
fsm->createLink(start_node, node, importer->net_map_at(net));
return node;
}
if (inst->Type() == PRIM_SVA_SEQ_CONCAT)
{
const char *sva_low_s = inst->GetAttValue("sva:low");
const char *sva_high_s = inst->GetAttValue("sva:high");
int sva_low = atoi(sva_low_s);
int sva_high = atoi(sva_high_s);
bool sva_inf = !strcmp(sva_high_s, "$");
int node = parse_sequence(fsm, start_node, inst->GetInput1());
for (int i = 0; i < sva_low; i++) {
int next_node = fsm->createNode();
fsm->createEdge(node, next_node);
node = next_node;
}
if (sva_inf)
{
fsm->createEdge(node, node);
}
else
{
for (int i = sva_low; i < sva_high; i++)
{
int next_node = fsm->createNode();
fsm->createEdge(node, next_node);
fsm->createLink(node, next_node);
node = next_node;
}
}
node = parse_sequence(fsm, node, inst->GetInput2());
return node;
}
if (inst->Type() == PRIM_SVA_CONSECUTIVE_REPEAT)
{
const char *sva_low_s = inst->GetAttValue("sva:low");
const char *sva_high_s = inst->GetAttValue("sva:high");
int sva_low = atoi(sva_low_s);
int sva_high = atoi(sva_high_s);
bool sva_inf = !strcmp(sva_high_s, "$");
int node = parse_sequence(fsm, start_node, inst->GetInput());
for (int i = 1; i < sva_low; i++)
{
int next_node = fsm->createNode();
fsm->createEdge(node, next_node);
node = parse_sequence(fsm, next_node, inst->GetInput());
}
if (sva_inf)
{
int next_node = fsm->createNode();
fsm->createEdge(node, next_node);
next_node = parse_sequence(fsm, next_node, inst->GetInput());
fsm->createLink(next_node, node);
}
else
{
for (int i = sva_low; i < sva_high; i++)
{
int next_node = fsm->createNode();
fsm->createEdge(node, next_node);
next_node = parse_sequence(fsm, next_node, inst->GetInput());
fsm->createLink(node, next_node);
node = next_node;
}
}
return node;
}
if (inst->Type() == PRIM_SVA_THROUGHOUT)
{
log_assert(get_ast_input1(inst) == nullptr);
SigBit expr = importer->net_map_at(inst->GetInput1());
fsm->pushThroughout(expr);
int node = parse_sequence(fsm, start_node, inst->GetInput2());
fsm->popThroughout();
return node;
}
// Handle unsupported primitives
if (!importer->mode_keep)
log_error("Verific SVA primitive %s (%s) is currently unsupported in this context.\n", inst->View()->Owner()->Name(), inst->Name());
log_warning("Verific SVA primitive %s (%s) is currently unsupported in this context.\n", inst->View()->Owner()->Name(), inst->Name());
return start_node;
}
void import()
{
module = importer->module;
netlist = root->Owner();
RTLIL::IdString root_name = module->uniquify(importer->mode_names || root->IsUserDeclared() ? RTLIL::escape_id(root->Name()) : NEW_ID);
// parse SVA property clock event
Instance *at_node = get_ast_input(root);
// asynchronous immediate assertion/assumption/cover
if (at_node == nullptr && (root->Type() == PRIM_SVA_IMMEDIATE_ASSERT ||
root->Type() == PRIM_SVA_IMMEDIATE_COVER || root->Type() == PRIM_SVA_IMMEDIATE_ASSUME))
{
SigSpec sig_a = importer->net_map_at(root->GetInput());
RTLIL::Cell *c = nullptr;
if (eventually) {
if (mode_assert) c = module->addLive(root_name, sig_a, State::S1);
if (mode_assume) c = module->addFair(root_name, sig_a, State::S1);
} else {
if (mode_assert) c = module->addAssert(root_name, sig_a, State::S1);
if (mode_assume) c = module->addAssume(root_name, sig_a, State::S1);
if (mode_cover) c = module->addCover(root_name, sig_a, State::S1);
}
importer->import_attributes(c->attributes, root);
return;
}
log_assert(at_node && at_node->Type() == PRIM_SVA_AT);
VerificClockEdge clock_edge(importer, get_ast_input1(at_node));
clock = clock_edge.clock_sig;
clock_posedge = clock_edge.posedge;
// parse disable_iff expression
Net *sequence_net = at_node->GetInput2();
while (1)
{
Instance *sequence_node = net_to_ast_driver(sequence_net);
if (sequence_node && sequence_node->Type() == PRIM_SVA_S_EVENTUALLY) {
eventually = true;
sequence_net = sequence_node->GetInput();
continue;
}
if (sequence_node && sequence_node->Type() == PRIM_SVA_DISABLE_IFF) {
disable_iff = importer->net_map_at(sequence_node->GetInput1());
sequence_net = sequence_node->GetInput2();
continue;
}
break;
}
// parse SVA sequence into trigger signal
SigBit prop_okay;
Instance *inst = net_to_ast_driver(sequence_net);
if (inst == nullptr)
{
prop_okay = importer->net_map_at(sequence_net);
}
else
if (inst->Type() == PRIM_SVA_OVERLAPPED_IMPLICATION ||
inst->Type() == PRIM_SVA_NON_OVERLAPPED_IMPLICATION)
{
Net *antecedent_net = inst->GetInput1();
Net *consequent_net = inst->GetInput2();
int node;
SvaFsm antecedent_fsm(module, clock, clock_posedge, disable_iff);
node = parse_sequence(&antecedent_fsm, antecedent_fsm.startNode, antecedent_net);
if (inst->Type() == PRIM_SVA_NON_OVERLAPPED_IMPLICATION) {
int next_node = antecedent_fsm.createNode();
antecedent_fsm.createEdge(node, next_node);
node = next_node;
}
antecedent_fsm.createLink(node, antecedent_fsm.acceptNode);
SigBit antecedent_accept = antecedent_fsm.getAccept();
antecedent_fsm.materialize_ndfsm();
antecedent_fsm.dump();
SvaFsm consequent_fsm(module, clock, clock_posedge, disable_iff, antecedent_accept);
node = parse_sequence(&consequent_fsm, consequent_fsm.startNode, consequent_net);
consequent_fsm.createLink(node, consequent_fsm.acceptNode);
SigBit consequent_reject = consequent_fsm.getReject();
prop_okay = module->Not(NEW_ID, consequent_reject);
if (consequent_fsm.is_linear())
consequent_fsm.materialize_ndfsm();
else
log_error("Currently only linear sequences are allowed as impliciation consequent.\n");
}
else
{
// Handle unsupported primitives
if (!importer->mode_keep)
log_error("Verific SVA primitive %s (%s) is currently unsupported in this context.\n", inst->View()->Owner()->Name(), inst->Name());
log_warning("Verific SVA primitive %s (%s) is currently unsupported in this context.\n", inst->View()->Owner()->Name(), inst->Name());
return;
}
// add final FF stage
Wire *prop_okay_q = module->addWire(NEW_ID);
prop_okay_q->attributes["\\init"] = Const(mode_cover ? 0 : 1, 1);
module->addDff(NEW_ID, clock, prop_okay, prop_okay_q, clock_posedge);
// generate assert/assume/cover cell
RTLIL::Cell *c = nullptr;
if (eventually) {
log_error("No support for eventually in Verific SVA bindings yet.\n");
// if (mode_assert) c = module->addLive(root_name, prop_okay_q, prop_start_q);
// if (mode_assume) c = module->addFair(root_name, prop_okay_q, prop_start_q);
} else {
if (mode_assert) c = module->addAssert(root_name, prop_okay_q, State::S1);
if (mode_assume) c = module->addAssume(root_name, prop_okay_q, State::S1);
if (mode_cover) c = module->addCover(root_name, prop_okay_q, State::S1);
}
importer->import_attributes(c->attributes, root);
}
#if 0
// ----------------------------------------------------------
// Old SVA Importer
vector<SigBit> sva_until_list_inclusive;
vector<SigBit> sva_until_list_exclusive;
vector<vector<SigBit>*> sva_sequence_alive_list;
@ -603,6 +1170,7 @@ struct VerificSvaImporter
importer->import_attributes(c->attributes, root);
}
#endif
};
void svapp_assert(Instance *inst)

View File

@ -5,7 +5,7 @@ module top (
default clocking @(posedge clk); endclocking
assert property (
a ##[*] b |=> c until ##[*] d
a ##[*] b |=> c until d
);
`ifndef FAIL