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Change BOOST_MATH_PROMOTE_DOUBLE_POLICY to false for non-x86
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Avoids a massive performance loss due to use of emulated 128 bit types.
Fixes issue #1211.
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Reimar Döffinger committed Nov 20, 2024
1 parent 8f843fd commit 2e28bd7
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Showing 2 changed files with 12 additions and 5 deletions.
13 changes: 10 additions & 3 deletions include/boost/math/policies/policy.hpp
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Expand Up @@ -111,10 +111,17 @@ namespace policies{
#define BOOST_MATH_PROMOTE_FLOAT_POLICY true
#endif
#ifndef BOOST_MATH_PROMOTE_DOUBLE_POLICY
#ifdef BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS
#define BOOST_MATH_PROMOTE_DOUBLE_POLICY false
#else
#if !defined(BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS) \
&& (defined(__i386) || defined(__i386__) || defined(_M_IX86) \
|| defined(__amd64) || defined(__amd64__) || defined(_M_AMD64) \
|| defined(__x86_64) || defined(__x86_64__) || defined(_M_X64))
// On non-x86 long double is expected to be either the same as double
// or an emulated 128 bit type - promotion is not sensible.
// On x86 long double is also rather slow these days, but changing the
// policy there has larger compatibility concerns and is left to a later time
#define BOOST_MATH_PROMOTE_DOUBLE_POLICY true
#else
#define BOOST_MATH_PROMOTE_DOUBLE_POLICY false
#endif
#endif
#ifndef BOOST_MATH_DISCRETE_QUANTILE_POLICY
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4 changes: 2 additions & 2 deletions test/test_policy_8.cpp
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Expand Up @@ -39,8 +39,8 @@ BOOST_AUTO_TEST_CASE( test_main )
BOOST_CHECK(check_same(make_policy(domain_error<ignore_error>(), pole_error<ignore_error>(), overflow_error<ignore_error>(), underflow_error<throw_on_error>(), denorm_error<throw_on_error>(), evaluation_error<ignore_error>(), indeterminate_result_error<throw_on_error>(), digits10<5>()), policy<domain_error<ignore_error>, pole_error<ignore_error>, overflow_error<ignore_error>, underflow_error<throw_on_error>, denorm_error<throw_on_error>, evaluation_error<ignore_error>, indeterminate_result_error<throw_on_error>, digits2<19> >()));
BOOST_CHECK(check_same(make_policy(domain_error<ignore_error>(), pole_error<ignore_error>(), overflow_error<ignore_error>(), underflow_error<throw_on_error>(), denorm_error<throw_on_error>(), evaluation_error<ignore_error>(), indeterminate_result_error<throw_on_error>(), digits2<10>(), promote_float<false>()), policy<domain_error<ignore_error>, pole_error<ignore_error>, overflow_error<ignore_error>, underflow_error<throw_on_error>, denorm_error<throw_on_error>, evaluation_error<ignore_error>, indeterminate_result_error<throw_on_error>, digits2<10>, promote_float<false> >()));
#ifndef BOOST_MATH_NO_LONG_DOUBLE_MATH_FUNCTIONS
BOOST_CHECK(check_same(make_policy(domain_error<ignore_error>(), pole_error<ignore_error>(), overflow_error<ignore_error>(), underflow_error<throw_on_error>(), denorm_error<throw_on_error>(), evaluation_error<ignore_error>(), indeterminate_result_error<throw_on_error>(), digits2<10>(), promote_float<false>(), promote_double<false>()), policy<domain_error<ignore_error>, pole_error<ignore_error>, overflow_error<ignore_error>, underflow_error<throw_on_error>, denorm_error<throw_on_error>, evaluation_error<ignore_error>, indeterminate_result_error<throw_on_error>, digits2<10>, promote_float<false>, promote_double<false> >()));
BOOST_CHECK(check_same(make_policy(domain_error<ignore_error>(), pole_error<ignore_error>(), overflow_error<ignore_error>(), underflow_error<throw_on_error>(), denorm_error<throw_on_error>(), evaluation_error<ignore_error>(), indeterminate_result_error<throw_on_error>(), digits2<10>(), promote_float<false>(), promote_double<false>(), discrete_quantile<integer_round_down>()), policy<domain_error<ignore_error>, pole_error<ignore_error>, overflow_error<ignore_error>, underflow_error<throw_on_error>, denorm_error<throw_on_error>, evaluation_error<ignore_error>, indeterminate_result_error<throw_on_error>, digits2<10>, promote_float<false>, promote_double<false>, discrete_quantile<integer_round_down> >()));
BOOST_CHECK(check_same(make_policy(domain_error<ignore_error>(), pole_error<ignore_error>(), overflow_error<ignore_error>(), underflow_error<throw_on_error>(), denorm_error<throw_on_error>(), evaluation_error<ignore_error>(), indeterminate_result_error<throw_on_error>(), digits2<10>(), promote_float<false>(), promote_double<!BOOST_MATH_PROMOTE_DOUBLE_POLICY>()), policy<domain_error<ignore_error>, pole_error<ignore_error>, overflow_error<ignore_error>, underflow_error<throw_on_error>, denorm_error<throw_on_error>, evaluation_error<ignore_error>, indeterminate_result_error<throw_on_error>, digits2<10>, promote_float<false>, promote_double<!BOOST_MATH_PROMOTE_DOUBLE_POLICY> >()));
BOOST_CHECK(check_same(make_policy(domain_error<ignore_error>(), pole_error<ignore_error>(), overflow_error<ignore_error>(), underflow_error<throw_on_error>(), denorm_error<throw_on_error>(), evaluation_error<ignore_error>(), indeterminate_result_error<throw_on_error>(), digits2<10>(), promote_float<false>(), promote_double<!BOOST_MATH_PROMOTE_DOUBLE_POLICY>(), discrete_quantile<integer_round_down>()), policy<domain_error<ignore_error>, pole_error<ignore_error>, overflow_error<ignore_error>, underflow_error<throw_on_error>, denorm_error<throw_on_error>, evaluation_error<ignore_error>, indeterminate_result_error<throw_on_error>, digits2<10>, promote_float<false>, promote_double<!BOOST_MATH_PROMOTE_DOUBLE_POLICY>, discrete_quantile<integer_round_down> >()));
#endif


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