smt2/smtbmc: Fix FF witness data for fine grained or multi chunk FFs

The witness metadata was missing fine grained FFs completely and for
coarse grained FFs where the output connection has multiple chunks it
lacked the offset of the chunk within the SMT expression. This fixes
both, the later by adding an "smtoffset" field to the metadata.
This commit is contained in:
Jannis Harder 2022-10-12 19:01:24 +02:00
parent f35c062354
commit 4d334fd3e3
4 changed files with 29 additions and 12 deletions

View File

@ -559,6 +559,9 @@ struct Smt2Worker
if (cell->type.in(ID($_FF_), ID($_DFF_P_), ID($_DFF_N_)))
{
registers.insert(cell);
SigBit q_bit = cell->getPort(ID::Q);
if (q_bit.is_wire())
decls.push_back(witness_signal("reg", 1, 0, "", idcounter, q_bit.wire));
makebits(stringf("%s#%d", get_id(module), idcounter), 0, log_signal(cell->getPort(ID::Q)));
register_bool(cell->getPort(ID::Q), idcounter++);
recursive_cells.erase(cell);
@ -589,9 +592,12 @@ struct Smt2Worker
if (cell->type.in(ID($ff), ID($dff)))
{
registers.insert(cell);
for (auto chunk : cell->getPort(ID::Q).chunks())
int smtoffset = 0;
for (auto chunk : cell->getPort(ID::Q).chunks()) {
if (chunk.is_wire())
decls.push_back(witness_signal("reg", chunk.width, chunk.offset, "", idcounter, chunk.wire));
decls.push_back(witness_signal("reg", chunk.width, chunk.offset, "", idcounter, chunk.wire, smtoffset));
smtoffset += chunk.width;
}
makebits(stringf("%s#%d", get_id(module), idcounter), GetSize(cell->getPort(ID::Q)), log_signal(cell->getPort(ID::Q)));
register_bv(cell->getPort(ID::Q), idcounter++);
recursive_cells.erase(cell);
@ -1490,7 +1496,7 @@ struct Smt2Worker
return path;
}
std::string witness_signal(const char *type, int width, int offset, const std::string &smtname, int smtid, RTLIL::Wire *wire)
std::string witness_signal(const char *type, int width, int offset, const std::string &smtname, int smtid, RTLIL::Wire *wire, int smtoffset = 0)
{
std::vector<std::string> hiername;
const char *wire_name = wire->name.c_str();
@ -1508,6 +1514,7 @@ struct Smt2Worker
{ "offset", offset },
{ "width", width },
{ "smtname", smtname.empty() ? json11::Json(smtid) : json11::Json(smtname) },
{ "smtoffset", smtoffset },
{ "path", witness_path(wire) },
}}).dump(line);
line += "\n";

View File

@ -669,7 +669,7 @@ if inywfile is not None:
if common_end <= common_offset:
continue
smt_expr = smt.net_expr(topmod, f"s{t}", wire["smtpath"])
smt_expr = smt.witness_net_expr(topmod, f"s{t}", wire)
if not smt_bool:
slice_high = common_end - offset - 1
@ -1267,7 +1267,8 @@ def write_yw_trace(steps_start, steps_stop, index, allregs=False):
sigs = seqs
for sig in sigs:
step_values[sig["sig"]] = smt.bv2bin(smt.get(smt.net_expr(topmod, f"s{k}", sig["smtpath"])))
value = smt.bv2bin(smt.get(smt.witness_net_expr(topmod, f"s{k}", sig)))
step_values[sig["sig"]] = value
yw.step(step_values)
yw.end_trace()

View File

@ -958,6 +958,15 @@ class SmtIo:
nextbase = "(|%s_h %s| %s)" % (mod, path[0], base)
return self.net_expr(nextmod, nextbase, path[1:])
def witness_net_expr(self, mod, base, witness):
net = self.net_expr(mod, base, witness["smtpath"])
is_bool = self.net_width(mod, witness["smtpath"]) == 1
if is_bool:
assert witness["width"] == 1
assert witness["smtoffset"] == 0
return net
return "((_ extract %d %d) %s)" % (witness["smtoffset"] + witness["width"] - 1, witness["smtoffset"], net)
def net_width(self, mod, net_path):
for i in range(len(net_path)-1):
assert mod in self.modinfo

View File

@ -4,14 +4,14 @@
(declare-fun |smtlib2_is| (|smtlib2_s|) Bool)
(declare-fun |smtlib2#0| (|smtlib2_s|) (_ BitVec 8)) ; \a
; yosys-smt2-input a 8
; yosys-smt2-witness {"offset": 0, "path": ["\\a"], "smtname": "a", "type": "input", "width": 8}
; yosys-smt2-witness {"offset": 0, "path": ["\\a"], "smtname": "a", "smtoffset": 0, "type": "input", "width": 8}
(define-fun |smtlib2_n a| ((state |smtlib2_s|)) (_ BitVec 8) (|smtlib2#0| state))
(declare-fun |smtlib2#1| (|smtlib2_s|) (_ BitVec 8)) ; \b
; yosys-smt2-input b 8
; yosys-smt2-witness {"offset": 0, "path": ["\\b"], "smtname": "b", "type": "input", "width": 8}
; yosys-smt2-witness {"offset": 0, "path": ["\\b"], "smtname": "b", "smtoffset": 0, "type": "input", "width": 8}
(define-fun |smtlib2_n b| ((state |smtlib2_s|)) (_ BitVec 8) (|smtlib2#1| state))
; yosys-smt2-output add 8
; yosys-smt2-witness {"offset": 0, "path": ["\\add"], "smtname": "add", "type": "blackbox", "width": 8}
; yosys-smt2-witness {"offset": 0, "path": ["\\add"], "smtname": "add", "smtoffset": 0, "type": "blackbox", "width": 8}
(define-fun |smtlib2_n add| ((state |smtlib2_s|)) (_ BitVec 8) (let (
(|a| (|smtlib2_n a| state))
(|b| (|smtlib2_n b| state))
@ -19,7 +19,7 @@
(bvadd a b)
))
; yosys-smt2-output eq 1
; yosys-smt2-witness {"offset": 0, "path": ["\\eq"], "smtname": "eq", "type": "blackbox", "width": 1}
; yosys-smt2-witness {"offset": 0, "path": ["\\eq"], "smtname": "eq", "smtoffset": 0, "type": "blackbox", "width": 1}
(define-fun |smtlib2_n eq| ((state |smtlib2_s|)) Bool (let (
(|a| (|smtlib2_n a| state))
(|b| (|smtlib2_n b| state))
@ -27,7 +27,7 @@
(= a b)
))
; yosys-smt2-output sub 8
; yosys-smt2-witness {"offset": 0, "path": ["\\sub"], "smtname": "sub", "type": "blackbox", "width": 8}
; yosys-smt2-witness {"offset": 0, "path": ["\\sub"], "smtname": "sub", "smtoffset": 0, "type": "blackbox", "width": 8}
(define-fun |smtlib2_n sub| ((state |smtlib2_s|)) (_ BitVec 8) (let (
(|a| (|smtlib2_n a| state))
(|b| (|smtlib2_n b| state))
@ -49,10 +49,10 @@
(declare-fun |uut#2| (|uut_s|) (_ BitVec 8)) ; \sub
(declare-fun |uut_h s| (|uut_s|) |smtlib2_s|)
; yosys-smt2-anyconst uut#3 8 smtlib2_module.v:14.17-14.26
; yosys-smt2-witness {"offset": 0, "path": ["\\a"], "smtname": 3, "type": "init", "width": 8}
; yosys-smt2-witness {"offset": 0, "path": ["\\a"], "smtname": 3, "smtoffset": 0, "type": "init", "width": 8}
(declare-fun |uut#3| (|uut_s|) (_ BitVec 8)) ; \a
; yosys-smt2-anyconst uut#4 8 smtlib2_module.v:14.32-14.41
; yosys-smt2-witness {"offset": 0, "path": ["\\b"], "smtname": 4, "type": "init", "width": 8}
; yosys-smt2-witness {"offset": 0, "path": ["\\b"], "smtname": 4, "smtoffset": 0, "type": "init", "width": 8}
(declare-fun |uut#4| (|uut_s|) (_ BitVec 8)) ; \b
(define-fun |uut#5| ((state |uut_s|)) (_ BitVec 8) (bvadd (|uut#3| state) (|uut#4| state))) ; \add2
(define-fun |uut#6| ((state |uut_s|)) Bool (= (|uut#0| state) (|uut#5| state))) ; $0$formal$smtlib2_module.v:28$1_CHECK[0:0]$9