* optabs.h (enum optab_index): Add new OTI_tan and OTI_atan.
(tan_optab, atan_optab): Define corresponding macros.
* optabs.c (init_optabs): Initialize tan_optab and atan_optab.
* genopinit.c (optabs): Implement tan_optab and atan_optab
using tan?f2 and atan?f2 patterns.
* builtins.c (expand_builtin_mathfn): Handle BUILT_IN_TAN{,F,L}
using tan_optab, and BUILT_IN_ATAN{,F,L} using atan_optab.
Change the default value of errno_set to false.
(expand_builtin): Expand BUILT_IN_TAN{,F,L} and BUILT_IN_ATAN{,F,L}
using expand_builtin_mathfn.
* config/i386/i386.md (atansf2, atandf2, atanxf2, atantf2): New
expander patterns implemented using existing atan2?f3 patterns.
* gcc.dg/i386-387-5.c: New test case.
* gcc.dg/i386-387-6.c: New test case.
* gcc.dg/builtins-23.c: New test case.
From-SVN: r68013
