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updates to param tuning

This commit is contained in:
Ilana Shapiro 2025-10-30 22:17:50 -07:00
parent 33060f7b97
commit 57d7e9fcf5
4 changed files with 62 additions and 86 deletions

View file

@ -137,7 +137,7 @@ namespace smt {
scoped_ptr<base_dependent_expr_state> m_fmls;
svector<double> m_lit_scores[2];
vector<literal_vector> m_recorded_clauses;
vector<expr_ref_vector> m_recorded_cubes;
// -----------------------------------
@ -1302,7 +1302,7 @@ namespace smt {
void add_scores(unsigned n, literal const *lits);
void record_clause(unsigned n, literal const * lits);
void record_cube(unsigned n, literal const * lits);
// -----------------------------------

View file

@ -966,10 +966,17 @@ namespace smt {
}
// following the pattern of solver::persist_clause in src/sat/smt/user_solver.cpp
void context::record_clause(unsigned num_lits, literal const *lits) {
literal_vector clause;
clause.append(num_lits, lits);
m_recorded_clauses.push_back(clause);
void context::record_cube(unsigned num_lits, literal const *lits) {
expr_ref_vector cube(m);
for (unsigned i = 0; i < num_lits; ++i) {
literal lit = lits[i];
expr* e = bool_var2expr(lit.var());
if (!e) continue;
if (!lit.sign())
e = m.mk_not(e); // only negate positive literal
cube.push_back(e);
}
m_recorded_cubes.push_back(cube);
}
void context::add_scores(unsigned n, literal const *lits) {
@ -1440,7 +1447,7 @@ namespace smt {
case CLS_LEARNED:
dump_lemma(num_lits, lits);
add_scores(num_lits, lits);
record_clause(num_lits, lits);
record_cube(num_lits, lits);
break;
default:
break;

View file

@ -83,36 +83,34 @@ namespace smt {
return r;
}
unsigned parallel::param_generator::replay_proof_prefixes(vector<param_values> const& candidate_param_states, unsigned max_conflicts_epsilon=200) {
std::pair<parallel::param_generator::param_values, bool> parallel::param_generator::replay_proof_prefixes(unsigned max_conflicts_epsilon=200) {
unsigned conflict_budget = m_max_prefix_conflicts + max_conflicts_epsilon;
unsigned best_param_state_idx;
param_values best_param_state;
double best_score;
bool found_better_params = false;
for (unsigned i = 0; i < m_param_probe_contexts.size(); ++i) {
for (unsigned i = 0; i < N; ++i) {
IF_VERBOSE(1, verbose_stream() << " PARAM TUNER: replaying proof prefix in param probe context " << i << "\n");
context *probe_ctx = m_param_probe_contexts[i];
// copy prefix solver context to a new probe_ctx for next replay with candidate mutation
scoped_ptr<context> probe_ctx = alloc(context, m, ctx->get_fparams(), m_p);
context::copy(*ctx, *probe_ctx, true);
// apply a candidate (mutated) param state to probe_ctx
// (except for the first iteration, use the current param state)
param_values mutated_param_state = m_param_state;
if (i > 0) {
mutated_param_state = mutate_param_state();
params_ref p = apply_param_values(mutated_param_state);
probe_ctx->updt_params(p);
}
probe_ctx->get_fparams().m_max_conflicts = conflict_budget;
double score = 0.0;
// apply the ith param state to probe_ctx
params_ref p = apply_param_values(candidate_param_states[i]);
probe_ctx->updt_params(p);
// todo: m_recorded_cubes as a expr_ref_vector
for (auto const& clause : probe_ctx->m_recorded_clauses) {
expr_ref_vector negated_lits(probe_ctx->m);
for (literal lit : clause) {
expr* e = probe_ctx->bool_var2expr(lit.var());
if (!e) continue; // skip if var not yet mapped
if (!lit.sign())
e = probe_ctx->m.mk_not(e); // since bool_var2expr discards sign
negated_lits.push_back(e);
}
// Replay the negated clause
lbool r = probe_ctx->check(negated_lits.size(), negated_lits.data());
// replay the cube (negation of the clause)
for (expr_ref_vector const& cube : probe_ctx->m_recorded_cubes) {
lbool r = probe_ctx->check(cube.size(), cube.data());
unsigned conflicts = probe_ctx->m_stats.m_num_conflicts;
unsigned decisions = probe_ctx->m_stats.m_num_decisions;
@ -120,13 +118,16 @@ namespace smt {
score += conflicts + decisions;
}
if (i == 0 || score < best_score) {
if (i > 0 && score < best_score) {
found_better_params = true;
best_param_state = mutated_param_state;
best_score = score;
} else {
best_score = score;
best_param_state_idx = i;
}
}
return best_param_state_idx;
return {best_param_state, found_better_params};
}
void parallel::param_generator::init_param_state() {
@ -147,7 +148,6 @@ namespace smt {
};
parallel::param_generator::param_values parallel::param_generator::mutate_param_state() {
param_values new_param_values(m_param_state);
unsigned index = ctx->get_random_value() % new_param_values.size();
auto &param = new_param_values[index];
@ -168,41 +168,23 @@ namespace smt {
void parallel::param_generator::protocol_iteration() {
IF_VERBOSE(1, verbose_stream() << " PARAM TUNER running protocol iteration\n");
ctx->get_fparams().m_max_conflicts = m_max_prefix_conflicts;
// copy current param state to all param probe contexts, before running the next prefix step
// this ensures that each param probe context replays the prefix from the same configuration
// instead just one one context and reset it each time before copy.
for (unsigned i = 0; i < m_param_probe_contexts.size(); ++i) {
context::copy(*ctx, *m_param_probe_contexts[i], true);
}
ctx->get_fparams().m_max_conflicts = m_max_prefix_conflicts;
lbool r = run_prefix_step();
switch (r) {
case l_undef: {
// TODO, change from smt_params to a generic param state representation based on params_ref
// only params_ref have effect on updates.
param_values best_param_state = m_param_state;
vector<param_values> candidate_param_states;
auto [best_param_state, found_better_params] = replay_proof_prefixes();
// you can create the mutations on the fly and get the scores
// you don't have to copy all over each tester.
candidate_param_states.push_back(best_param_state); // first candidate param state is current best
while (candidate_param_states.size() <= N) {
candidate_param_states.push_back(mutate_param_state());
}
unsigned best_param_state_idx = replay_proof_prefixes(candidate_param_states);
if (best_param_state_idx != 0) {
m_param_state = candidate_param_states[best_param_state_idx];
// NOTE: we either need to return a pair from replay_proof_prefixes so we can return a boolean flag indicating whether better params were found.
// or, we have to implement a comparison operator for param_values
// or, we update the param state every single time even if it hasn't changed
// for now, I went with option 1
if (found_better_params) {
m_param_state = best_param_state;
auto p = apply_param_values(m_param_state);
b.set_param_state(p);
IF_VERBOSE(1, verbose_stream() << " PARAM TUNER found better param state at index " << best_param_state_idx << "\n");
IF_VERBOSE(1, verbose_stream() << " PARAM TUNER found better param state\n");
} else {
IF_VERBOSE(1, verbose_stream() << " PARAM TUNER retained current param state\n");
}
@ -315,11 +297,6 @@ namespace smt {
: p(p), b(p.m_batch_manager), m_p(p.ctx.get_params()), m_l2g(m, p.ctx.m) {
ctx = alloc(context, m, p.ctx.get_fparams(), m_p);
context::copy(p.ctx, *ctx, true);
for (unsigned i = 0; i < N; ++i) {
m_param_probe_contexts.push_back(alloc(context, m, ctx->get_fparams(), m_p));
}
// don't share initial units
ctx->pop_to_base_lvl();
init_param_state();

View file

@ -27,23 +27,6 @@ Revision History:
namespace smt {
inline bool operator==(const smt_params& a, const smt_params& b) {
return a.m_nl_arith_branching == b.m_nl_arith_branching &&
a.m_nl_arith_cross_nested == b.m_nl_arith_cross_nested &&
a.m_nl_arith_delay == b.m_nl_arith_delay &&
a.m_nl_arith_expensive_patching == b.m_nl_arith_expensive_patching &&
a.m_nl_arith_gb == b.m_nl_arith_gb &&
a.m_nl_arith_horner == b.m_nl_arith_horner &&
a.m_nl_arith_horner_frequency == b.m_nl_arith_horner_frequency &&
a.m_nl_arith_optimize_bounds == b.m_nl_arith_optimize_bounds &&
a.m_nl_arith_propagate_linear_monomials == b.m_nl_arith_propagate_linear_monomials &&
a.m_nl_arith_tangents == b.m_nl_arith_tangents;
}
inline bool operator!=(const smt_params& a, const smt_params& b) {
return !(a == b);
}
struct cube_config {
using literal = expr_ref;
static bool literal_is_null(expr_ref const& l) { return l == nullptr; }
@ -150,9 +133,18 @@ namespace smt {
param_values m_param_state;
params_ref apply_param_values(param_values const &pv) {
return m_p;
params_ref p = m_p;
for (auto const& [k, v] : pv) {
if (std::holds_alternative<unsigned_value>(v)) {
unsigned_value uv = std::get<unsigned_value>(v);
p.set_uint(k, uv.value);
} else if (std::holds_alternative<bool>(v)) {
bool bv = std::get<bool>(v);
p.set_bool(k, bv);
}
}
return p;
}
// todo
private:
void init_param_state();
@ -163,7 +155,7 @@ namespace smt {
param_generator(parallel &p);
lbool run_prefix_step();
void protocol_iteration();
unsigned replay_proof_prefixes(vector<param_values> const& candidate_param_states, unsigned max_conflicts_epsilon);
std::pair<parallel::param_generator::param_values, bool> replay_proof_prefixes(unsigned max_conflicts_epsilon);
reslimit &limit() {
return m.limit();