math: Use wordsize-64 version for isnan

System Internals / glibc - Adhemerval Zanella [] - 12 June 2019 17:32 EDT

- math.h will use compiler builtin for gcc 4.4 when built without-fsignaling-nans and the builtin is expanded inline for all support architectures. As an example, there is no intra isnan call on libm for the architecture I checked, x86, arm, aarch64, and powerpc.

- The resulting binary difference on 32 bits architecture is minimum for the non hotspot symbol.

- It helps wordsize-64 architectures that use ldbl-opt.

- It add some code simplification with reduction of duplicated implementations.

Checked on powerpc-linux-gnu (built without --with-cpu, with--with-cpu=power4 and with --with-cpu=power5+ and --disable-multi-arch), powerpc64-linux-gnu (built without --with-cp and with --with-cpu=power5+ and --disable-multi-arch).

- sysdeps/ieee754/dbl-64/wordsize-64/s_isnan.c: Move to ...
- sysdeps/ieee754/dbl-64/s_isnan.c: ... here and format code.

197dbda1a1 math: Use wordsize-64 version for isnan
ChangeLog | 3 +++
sysdeps/ieee754/dbl-64/s_isnan.c | 17 +++++-------
sysdeps/ieee754/dbl-64/wordsize-64/s_isnan.c | 40 ----------------------------
3 files changed, 9 insertions(+), 51 deletions(-)


  • Share