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concrete/compilers/concrete-compiler/compiler/lib/Support/V0Parameters.cpp

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// Part of the Concrete Compiler Project, under the BSD3 License with Zama
// Exceptions. See
// https://github.com/zama-ai/concrete-compiler-internal/blob/main/LICENSE.txt
// for license information.
/// DO NOT MANUALLY EDIT THIS FILE.
/// This file was generated thanks the "parameters optimizer".
/// We should include this in our build system, but for moment it is just a cc
/// from the optimizer output.
#include <cassert>
#include <chrono>
#include <cmath>
#include <iostream>
#include <optional>
#include "llvm/Support/raw_ostream.h"
#include "concrete-optimizer.hpp"
#include "concretelang/Support/Error.h"
#include "concretelang/Support/V0Parameters.h"
#include "concretelang/Support/logging.h"
namespace mlir {
namespace concretelang {
concrete_optimizer::Options options_from_config(optimizer::Config config) {
concrete_optimizer::Options options = {
/* .security_level = */ config.security,
/* .maximum_acceptable_error_probability = */ config.p_error,
/* .default_log_norm2_woppbs = */ config.fallback_log_norm_woppbs,
/* .use_gpu_constraints = */ config.use_gpu_constraints,
/* .encoding = */ config.encoding,
/* .cache_on_disk = */ config.cache_on_disk,
};
return options;
}
optimizer::DagSolution getV0Parameter(V0FHEConstraint constraint,
optimizer::Config config) {
// the norm2 0 is equivalent to a maximum noise_factor of 2.0
// norm2 = 0 ==> 1.0 =< noise_factor < 2.0
// norm2 = k ==> 2^norm2 =< noise_factor < 2.0^norm2 + 1
double noise_factor = std::exp2(constraint.norm2 + 1);
auto options = options_from_config(config);
auto solution = concrete_optimizer::v0::optimize_bootstrap(
constraint.p, noise_factor, options);
return concrete_optimizer::utils::convert_to_dag_solution(solution);
}
const int MAXIMUM_OPTIMIZER_CALL = 10;
optimizer::DagSolution getV1ParameterGlobalPError(optimizer::Dag &dag,
optimizer::Config config) {
// We find the approximate translation between local and global error with a
// calibration call
auto ref_global_p_success = 1.0 - config.global_p_error;
auto options = options_from_config(config);
options.maximum_acceptable_error_probability =
std::min(config.p_error, config.global_p_error);
auto sol = dag->optimize(options);
if (sol.global_p_error <= config.global_p_error) {
// for levelled circuit the error is almost zero
return sol;
}
for (int i = 2; i <= MAXIMUM_OPTIMIZER_CALL; i++) {
auto local_p_success = 1.0 - sol.p_error;
auto global_p_success = 1.0 - sol.global_p_error;
auto power_global_to_local = log(local_p_success) / log(global_p_success);
auto surrogate_p_local_success =
pow(ref_global_p_success, power_global_to_local);
auto surrogate_p_error = 1.0 - surrogate_p_local_success;
// only valid when p_error is not too small and global_p_error not too high
auto valid = 0 < surrogate_p_error && surrogate_p_error < 1.0;
if (!valid) {
// linear approximation, only precise for small p_error
auto linear_correction =
sol.p_error < 0.1 ? sol.p_error / sol.global_p_error : 0.1;
valid = 0.0 < linear_correction && linear_correction < 1.0;
if (!valid) {
// global_p_error could be 0
linear_correction = 1e-5;
}
surrogate_p_error =
options.maximum_acceptable_error_probability * linear_correction;
};
options.maximum_acceptable_error_probability = surrogate_p_error;
sol = dag->optimize(options);
if (sol.global_p_error <= config.global_p_error) {
break;
}
}
return sol;
}
optimizer::DagSolution getV1Parameter(optimizer::Dag &dag,
optimizer::Config config) {
if (!std::isnan(config.global_p_error)) {
return getV1ParameterGlobalPError(dag, config);
}
auto options = options_from_config(config);
return dag->optimize(options);
}
constexpr double WARN_ABOVE_GLOBAL_ERROR_RATE = 1.0 / 1000.0;
static void display(optimizer::Description &descr,
optimizer::Config optimizerConfig,
optimizer::DagSolution sol, bool naive_user,
std::chrono::milliseconds duration) {
if (!optimizerConfig.display && !mlir::concretelang::isVerbose()) {
return;
}
auto constraint = descr.constraint;
auto complexity_label =
descr.dag ? "for the full circuit" : "for each Pbs call";
double mops = ceil(sol.complexity / (1000 * 1000));
auto o = llvm::outs;
o() << "--- Circuit\n"
<< " " << constraint.p << " bits integers\n"
<< " " << constraint.norm2 << " manp (maxi log2 norm2)\n"
<< " " << duration.count() << "ms to solve\n"
<< "--- User config\n"
<< " " << optimizerConfig.p_error << " error per pbs call\n";
if (!std::isnan(optimizerConfig.global_p_error)) {
o() << " " << optimizerConfig.global_p_error
<< " error per circuit call\n";
}
o() << "--- Complexity " << complexity_label << "\n"
<< " " << mops << " Millions Operations\n"
<< "--- Correctness for each Pbs call\n"
<< " 1/" << int(1.0 / sol.p_error) << " errors (" << sol.p_error
<< ")\n";
if (descr.dag && !std::isnan(sol.global_p_error)) {
o() << "--- Correctness for the full circuit\n"
<< " 1/" << int(1.0 / sol.global_p_error) << " errors ("
<< sol.global_p_error << ")\n";
}
o() << "--- Parameters resolution\n"
<< " " << sol.glwe_dimension << "x glwe_dimension\n"
<< " 2**" << (size_t)std::log2l(sol.glwe_polynomial_size)
<< " polynomial (" << sol.glwe_polynomial_size << ")\n"
<< " " << sol.internal_ks_output_lwe_dimension << " lwe dimension \n"
<< " keyswitch l,b=" << sol.ks_decomposition_level_count << ","
<< sol.ks_decomposition_base_log << "\n"
<< " blindrota l,b=" << sol.br_decomposition_level_count << ","
<< sol.br_decomposition_base_log << "\n"
<< " wopPbs : " << (sol.use_wop_pbs ? "true" : "false") << "\n";
if (sol.use_wop_pbs) {
o() << " |cb_decomp l,b=" << sol.cb_decomposition_level_count << ","
<< sol.cb_decomposition_base_log << "\n"
<< " |pp_decomp l,b=" << sol.pp_decomposition_level_count << ","
<< sol.pp_decomposition_base_log << "\n";
}
o() << "---\n";
if (descr.dag && naive_user &&
sol.global_p_error > WARN_ABOVE_GLOBAL_ERROR_RATE) {
auto dominating_pbs =
(int)(log(1.0 - sol.global_p_error) / log(1.0 - sol.p_error));
o() << "---\n"
<< "!!!!! WARNING !!!!!\n"
<< "\n"
<< "HIGH ERROR RATE: 1/" << int(1.0 / sol.global_p_error)
<< " errors \n\n"
<< "Resolve by using command line option: \n"
<< "--global-error-probability=" << WARN_ABOVE_GLOBAL_ERROR_RATE
<< "\n\n"
<< "Reason:\n"
<< dominating_pbs << " pbs dominate at 1/" << int(1.0 / sol.p_error)
<< " errors rate\n";
o() << "\n!!!!!!!!!!!!!!!!!!!\n";
}
}
llvm::Expected<V0Parameter> getParameter(optimizer::Description &descr,
CompilationFeedback &feedback,
optimizer::Config config) {
namespace chrono = std::chrono;
auto start = chrono::high_resolution_clock::now();
auto naive_user =
std::isnan(config.p_error) && std::isnan(config.global_p_error);
if (naive_user) {
config.global_p_error = optimizer::DEFAULT_GLOBAL_P_ERROR;
}
if (std::isnan(config.p_error)) {
// We always need a valid p-error
// getV0Parameter relies only on p_error
// getV1Parameter relies on p-error and if set global-p-error
config.p_error = config.global_p_error;
}
auto sol = (!descr.dag || config.strategy_v0)
? getV0Parameter(descr.constraint, config)
: getV1Parameter(descr.dag.value(), config);
auto stop = chrono::high_resolution_clock::now();
auto duration = chrono::duration_cast<chrono::milliseconds>(stop - start);
auto duration_s = chrono::duration_cast<chrono::seconds>(duration);
if (duration_s.count() > 3) {
llvm::errs() << "concrete-optimizer time: " << duration_s.count() << "s\n";
}
display(descr, config, sol, naive_user, duration);
// The optimizer return a p_error = 1 if there is no solution
bool no_solution = sol.p_error == 1.0;
// The global_p_error is best effort only, so we must verify
bool bad_solution = !std::isnan(config.global_p_error) &&
config.global_p_error < sol.global_p_error;
if (no_solution || bad_solution) {
return StreamStringError() << "Cannot find crypto parameters";
}
if (descr.dag && !config.display && naive_user &&
sol.global_p_error > WARN_ABOVE_GLOBAL_ERROR_RATE) {
llvm::errs() << "WARNING: high error rate, more details with "
"--display-optimizer-choice\n";
}
V0Parameter params;
params.glweDimension = sol.glwe_dimension;
params.logPolynomialSize = (size_t)std::log2l(sol.glwe_polynomial_size);
params.nSmall = sol.internal_ks_output_lwe_dimension;
params.brLevel = sol.br_decomposition_level_count;
params.brLogBase = sol.br_decomposition_base_log;
params.ksLevel = sol.ks_decomposition_level_count;
params.ksLogBase = sol.ks_decomposition_base_log;
params.largeInteger = std::nullopt;
if (sol.use_wop_pbs) {
if (sol.crt_decomposition.empty()) {
// TODO: FIXME
llvm::errs() << "FIXME: optimizer didn't returns the crt_decomposition\n";
sol.crt_decomposition = {7, 8, 9, 11, 13};
}
LargeIntegerParameter lParams;
for (auto m : sol.crt_decomposition) {
lParams.crtDecomposition.push_back(m);
}
lParams.wopPBS.circuitBootstrap.baseLog = sol.cb_decomposition_base_log;
lParams.wopPBS.circuitBootstrap.level = sol.cb_decomposition_level_count;
lParams.wopPBS.packingKeySwitch.inputLweDimension =
sol.internal_ks_output_lwe_dimension + 1;
lParams.wopPBS.packingKeySwitch.outputPolynomialSize =
sol.glwe_polynomial_size;
lParams.wopPBS.packingKeySwitch.level = sol.pp_decomposition_level_count;
lParams.wopPBS.packingKeySwitch.baseLog = sol.pp_decomposition_base_log;
params.largeInteger = lParams;
}
feedback.complexity = sol.complexity;
feedback.pError = sol.p_error;
feedback.globalPError =
std::isnan(sol.global_p_error) ? 0 : sol.global_p_error;
return params;
}
} // namespace concretelang
} // namespace mlir