Summary:
Currently std::asinh and std::acosh use std::pow to compute x^2. This
results in a significant error when computing e.g. asinh(i) or
acosh(-1).
This patch expresses x^2 directly via x.real() and x.imag(), like it
is done in libstdc++/glibc, and adds tests that checks the accuracy.
Reviewers: EricWF, mclow.lists
Reviewed By: mclow.lists
Subscribers: christof, cfe-commits
Differential Revision: https://reviews.llvm.org/D41629
llvm-svn: 325510
r283051 added some functions to cmath (in namespace std) that have the
same name as functions in math.h (in the global namespace). Clang's
limited support for `-fdelayed-template-parsing` chokes on this. Rename
the ones in `cmath` and their uses in `complex` and the test.
rdar://problem/32848355
llvm-svn: 307357
The name _LIBCPP_TYPE_VIS_ONLY is no longer accurate because both
_LIBCPP_TYPE_VIS and _LIBCPP_TYPE_VIS_ONLY expand to
__attribute__((__type_visibility__)) with Clang. The only remaining difference
is that _LIBCPP_TYPE_VIS_ONLY can be applied to templates whereas
_LIBCPP_TYPE_VIS cannot (due to dllimport/dllexport not being allowed on
templates).
This patch renames _LIBCPP_TYPE_VIS_ONLY to _LIBCPP_TEMPLATE_VIS.
llvm-svn: 291035
The libc-provided isnan/isinf/isfinite macro implementations are specifically
designed to function correctly, even in the presence of -ffast-math (or, more
specifically, -ffinite-math-only). As such, on most implementation, these
either always turn into external function calls (e.g. glibc) or are
specifically function calls when FINITE_MATH_ONLY is defined (e.g. Darwin).
Our implementation of complex arithmetic makes heavy use of isnan/isinf/isfinite
to deal with corner cases involving non-finite quantities. This was problematic
in two respects:
1. On systems where these are always function calls (e.g. Linux/glibc), there was a
performance penalty
2. When compiling with -ffast-math, there was a significant performance
penalty (in fact, on Darwin and systems with similar implementations, the code
may in fact be slower than not using -ffast-math, because the inline
definitions provided by libc become unavailable to prevent the checks from
being optimized out).
Eliding these inf/nan checks in -ffast-math mode is consistent with what
happens with libstdc++, and in my experience, what users expect. This is
critical to getting high-performance code when using complex<T>. This change
replaces uses of those functions on basic floating-point types with calls to
__builtin_isnan/isinf/isfinite, which Clang will always expand inline. When
using -ffast-math (or -ffinite-math-only), the optimizer will remove the checks
as expected.
Differential Revision: https://reviews.llvm.org/D18639
llvm-svn: 283051
The functions arg, conj, imag, norm, proj, and real have additional overloads
for arguments of integral or floating point types. However these overloads should
not allow conversions to the integral/floating point types, only exact matches.
This patch constrains these functions so they no longer allow conversions.
llvm-svn: 276067