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Member "ginac-1.6.2/ginac/excompiler.cpp" of archive ginac-1.6.2.tar.gz:
/** @file excompiler.cpp
*
* Functions to facilitate the conversion of a ex to a function pointer suited for
* fast numerical integration.
*
*/
/*
* GiNaC Copyright (C) 1999-2011 Johannes Gutenberg University Mainz, Germany
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "excompiler.h"
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "ex.h"
#include "lst.h"
#include "operators.h"
#include "relational.h"
#include "symbol.h"
#ifdef HAVE_LIBDL
#include <dlfcn.h>
#endif // def HAVE_LIBDL
#include <fstream>
#include <ios>
#include <sstream>
#include <stdexcept>
#include <string>
#include <vector>
namespace GiNaC {
#ifdef HAVE_LIBDL
/**
* Small class that manages modules opened by libdl. It is used by compile_ex
* and link_ex in order to have a clean-up of opened modules and their
* associated source and so-files at the time of program termination. It is
* supposed to be statically instantiated once (see definition of
* global_excompiler below). The dtor of that object then performs the
* clean-up. On top of that it provides some functionality shared between
* different compile_ex and link_ex specializations.
*/
class excompiler
{
/**
* Holds all necessary information about opened modules.
*/
struct filedesc
{
void* module;
std::string name; /**< filename with .so suffix */
bool clean_up; /**< if true, source and so-file will be deleted */
};
std::vector<filedesc> filelist; /**< List of all opened modules */
public:
/**
* Complete clean-up of opend modules is done on destruction.
*/
~excompiler()
{
for (std::vector<filedesc>::const_iterator it = filelist.begin(); it != filelist.end(); ++it) {
clean_up(it);
}
}
/**
* Adds a new module to the list.
*/
void add_opened_module(void* module, const std::string& name, bool clean_up)
{
filedesc fd;
fd.module = module;
fd.name = name;
fd.clean_up = clean_up;
filelist.push_back(fd);
}
/**
* Closes a module and deletes the so-file if the associated clean-up flag is true.
*/
void clean_up(const std::vector<filedesc>::const_iterator it)
{
dlclose(it->module);
if (it->clean_up) {
remove(it->name.c_str());
}
}
/**
* Creates a new C source file and adds a standard header. If filename is
* empty, a unique random name is produced and used.
*/
void create_src_file(std::string& filename, std::ofstream& ofs)
{
if (filename.empty()) {
// fill filename with unique random word
const char* filename_pattern = "./GiNaCXXXXXX";
char* new_filename = new char[strlen(filename_pattern)+1];
strcpy(new_filename, filename_pattern);
if (!mktemp(new_filename)) {
delete[] new_filename;
throw std::runtime_error("mktemp failed");
}
filename = std::string(new_filename);
ofs.open(new_filename, std::ios::out);
delete[] new_filename;
} else {
// use parameter as filename
ofs.open(filename.c_str(), std::ios::out);
}
if (!ofs) {
throw std::runtime_error("could not create source code file for compilation");
}
ofs << "#include <stddef.h> " << std::endl;
ofs << "#include <stdlib.h> " << std::endl;
ofs << "#include <math.h> " << std::endl;
ofs << std::endl;
}
/**
* Calls the shell script 'ginac-excompiler' to compile the produced C
* source file into an linkable so-file. On demand the C source file is
* deleted.
*/
void compile_src_file(const std::string filename, bool clean_up)
{
std::string strcompile = "ginac-excompiler " + filename;
if (system(strcompile.c_str())) {
throw std::runtime_error("excompiler::compile_src_file: error compiling source file!");
}
if (clean_up) {
remove(filename.c_str());
}
}
/**
* Links a so-file whose filename is given.
*/
void* link_so_file(const std::string filename, bool clean_up)
{
void* module = NULL;
module = dlopen(filename.c_str(), RTLD_NOW);
if (module == NULL) {
throw std::runtime_error("excompiler::link_so_file: could not open compiled module!");
}
add_opened_module(module, filename, clean_up);
return dlsym(module, "compiled_ex");
}
/**
* Removes a modules from the module list. Performs a clean-up before that.
* Every module with the given name will be affected.
*/
void unlink(const std::string filename)
{
for (std::vector<filedesc>::iterator it = filelist.begin(); it != filelist.end();) {
if (it->name == filename) {
clean_up(it);
it = filelist.erase(it);
} else {
++it;
}
}
}
};
/**
* This static object manages the modules opened by the complile_ex and link_ex
* functions. On program termination its dtor is called and all open modules
* are closed. The associated source and so-files are eventually deleted then
* as well.
* In principle this could lead to a static deconstruction order fiasco, if
* other code from this library uses the compile_ex and link_ex functions
* (which it doesn't at the moment and won't in the likely future, so therefore
* we ignore this issue).
*/
static excompiler global_excompiler;
void compile_ex(const ex& expr, const symbol& sym, FUNCP_1P& fp, const std::string filename)
{
symbol x("x");
ex expr_with_x = expr.subs(lst(sym==x));
std::ofstream ofs;
std::string unique_filename = filename;
global_excompiler.create_src_file(unique_filename, ofs);
ofs << "double compiled_ex(double x)" << std::endl;
ofs << "{" << std::endl;
ofs << "double res = ";
expr_with_x.print(GiNaC::print_csrc_double(ofs));
ofs << ";" << std::endl;
ofs << "return(res); " << std::endl;
ofs << "}" << std::endl;
ofs.close();
global_excompiler.compile_src_file(unique_filename, filename.empty());
// This is not standard compliant! ... no conversion between
// pointer-to-functions and pointer-to-objects ...
fp = (FUNCP_1P) global_excompiler.link_so_file(unique_filename+".so", filename.empty());
}
void compile_ex(const ex& expr, const symbol& sym1, const symbol& sym2, FUNCP_2P& fp, const std::string filename)
{
symbol x("x"), y("y");
ex expr_with_xy = expr.subs(lst(sym1==x, sym2==y));
std::ofstream ofs;
std::string unique_filename = filename;
global_excompiler.create_src_file(unique_filename, ofs);
ofs << "double compiled_ex(double x, double y)" << std::endl;
ofs << "{" << std::endl;
ofs << "double res = ";
expr_with_xy.print(GiNaC::print_csrc_double(ofs));
ofs << ";" << std::endl;
ofs << "return(res); " << std::endl;
ofs << "}" << std::endl;
ofs.close();
global_excompiler.compile_src_file(unique_filename, filename.empty());
// This is not standard compliant! ... no conversion between
// pointer-to-functions and pointer-to-objects ...
fp = (FUNCP_2P) global_excompiler.link_so_file(unique_filename+".so", filename.empty());
}
void compile_ex(const lst& exprs, const lst& syms, FUNCP_CUBA& fp, const std::string filename)
{
lst replacements;
for (std::size_t count=0; count<syms.nops(); ++count) {
std::ostringstream s;
s << "a[" << count << "]";
replacements.append(syms.op(count) == symbol(s.str()));
}
std::vector<ex> expr_with_cname;
for (std::size_t count=0; count<exprs.nops(); ++count) {
expr_with_cname.push_back(exprs.op(count).subs(replacements));
}
std::ofstream ofs;
std::string unique_filename = filename;
global_excompiler.create_src_file(unique_filename, ofs);
ofs << "void compiled_ex(const int* an, const double a[], const int* fn, double f[])" << std::endl;
ofs << "{" << std::endl;
for (std::size_t count=0; count<exprs.nops(); ++count) {
ofs << "f[" << count << "] = ";
expr_with_cname[count].print(GiNaC::print_csrc_double(ofs));
ofs << ";" << std::endl;
}
ofs << "}" << std::endl;
ofs.close();
global_excompiler.compile_src_file(unique_filename, filename.empty());
// This is not standard compliant! ... no conversion between
// pointer-to-functions and pointer-to-objects ...
fp = (FUNCP_CUBA) global_excompiler.link_so_file(unique_filename+".so", filename.empty());
}
void link_ex(const std::string filename, FUNCP_1P& fp)
{
// This is not standard compliant! ... no conversion between
// pointer-to-functions and pointer-to-objects ...
fp = (FUNCP_1P) global_excompiler.link_so_file(filename, false);
}
void link_ex(const std::string filename, FUNCP_2P& fp)
{
// This is not standard compliant! ... no conversion between
// pointer-to-functions and pointer-to-objects ...
fp = (FUNCP_2P) global_excompiler.link_so_file(filename, false);
}
void link_ex(const std::string filename, FUNCP_CUBA& fp)
{
// This is not standard compliant! ... no conversion between
// pointer-to-functions and pointer-to-objects ...
fp = (FUNCP_CUBA) global_excompiler.link_so_file(filename, false);
}
void unlink_ex(const std::string filename)
{
global_excompiler.unlink(filename);
}
#else // def HAVE_LIBDL
/*
* In case no working libdl has been found by configure, the following function
* stubs preserve the interface. Every function just raises an exception.
*/
void compile_ex(const ex& expr, const symbol& sym, FUNCP_1P& fp, const std::string filename)
{
throw std::runtime_error("compile_ex has been disabled because of missing libdl!");
}
void compile_ex(const ex& expr, const symbol& sym1, const symbol& sym2, FUNCP_2P& fp, const std::string filename)
{
throw std::runtime_error("compile_ex has been disabled because of missing libdl!");
}
void compile_ex(const lst& exprs, const lst& syms, FUNCP_CUBA& fp, const std::string filename)
{
throw std::runtime_error("compile_ex has been disabled because of missing libdl!");
}
void link_ex(const std::string filename, FUNCP_1P& fp)
{
throw std::runtime_error("link_ex has been disabled because of missing libdl!");
}
void link_ex(const std::string filename, FUNCP_2P& fp)
{
throw std::runtime_error("link_ex has been disabled because of missing libdl!");
}
void link_ex(const std::string filename, FUNCP_CUBA& fp)
{
throw std::runtime_error("link_ex has been disabled because of missing libdl!");
}
void unlink_ex(const std::string filename)
{
throw std::runtime_error("unlink_ex has been disabled because of missing libdl!");
}
#endif // def HAVE_LIBDL
} // namespace GiNaC