compute/test/test_literal_conversion.cpp
Jason Rhinelander 9b2c65fee9 Work around libc++ bug 17782
libc++ fails to extract a valid float/double literal when it is followed
by any special characters that can also be found in a float value,
in this case, f (https://llvm.org/bugs/show_bug.cgi?id=17782).

This commit works around the problem by not putting the "f" suffix into
the string for extraction.
2016-05-03 10:21:02 -04:00

73 lines
2.8 KiB
C++

//---------------------------------------------------------------------------//
// Copyright (c) 2016 Jason Rhinelander <jason@imaginary.ca>
//
// Distributed under the Boost Software License, Version 1.0
// See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt
//
// See http://boostorg.github.com/compute for more information.
//---------------------------------------------------------------------------//
#define BOOST_TEST_MODULE TestLiteralConversion
#include <boost/test/unit_test.hpp>
#include <string>
#include <sstream>
#include <vector>
#include <boost/compute/detail/literal.hpp>
BOOST_AUTO_TEST_CASE(literal_conversion_float)
{
std::vector<float> values, roundtrip;
values.push_back(1.2345679f);
values.push_back(1.2345680f);
values.push_back(1.2345681f);
for (size_t i = 0; i < values.size(); i++) {
std::string literal = boost::compute::detail::make_literal(values[i]);
// Check that we got something in the literal, and that at least the first
// 6 characters (5 digits) look good
BOOST_CHECK_EQUAL(literal.substr(0, 6), "1.2345");
// libc++ stream extraction fails on a value such as "1.2f" rather than extracting 1.2
// and leaving the f; so check the "f", then slice it off for the extraction below:
BOOST_CHECK_EQUAL(literal.substr(literal.length()-1), "f");
std::istringstream iss(literal.substr(0, literal.length()-1));
float x;
iss >> x;
roundtrip.push_back(x);
}
BOOST_CHECK_EQUAL(values[0], roundtrip[0]);
BOOST_CHECK_EQUAL(values[1], roundtrip[1]);
BOOST_CHECK_EQUAL(values[2], roundtrip[2]);
}
BOOST_AUTO_TEST_CASE(literal_conversion_double)
{
std::vector<double> values, roundtrip;
values.push_back(1.2345678901234567);
values.push_back(1.2345678901234569);
values.push_back(1.2345678901234571);
for (size_t i = 0; i < values.size(); i++) {
std::string literal = boost::compute::detail::make_literal(values[i]);
// Check that we got something in the literal, and that at least the first
// 11 characters (10 digits) look good
BOOST_CHECK_EQUAL(literal.substr(0, 11), "1.234567890");
// Stuff the literal into a stream then extract it, and make sure we get a numerically
// identical result. (Since there is no suffix, we don't have to worry about removing the
// suffix like we have to above, for float--but we also check to make sure there is no
// (unextracted) suffix).
std::istringstream iss(literal);
double x;
std::string suffix;
iss >> x >> suffix;
BOOST_CHECK_EQUAL(suffix, "");
roundtrip.push_back(x);
}
BOOST_CHECK_EQUAL(values[0], roundtrip[0]);
BOOST_CHECK_EQUAL(values[1], roundtrip[1]);
BOOST_CHECK_EQUAL(values[2], roundtrip[2]);
}