soft-fp: Add fixhf[uns][di|si] and float[uns][di|si]hf

Add more IEEE half conversion routines:

- Convert 32-bit/64-bit integer to IEEE half.
- Convert IEEE half to 32-bit/64-bit integer.

They are required by RISC-V _Float16 support, tested with RISC-V GCC.

1 files changed, 45 insertions, 0 deletions

diff --git a/soft-fp/floatsihf.c b/soft-fp/floatsihf.c
new file mode 100644
index 0000000000..2caa11d99c
--- /dev/null
+++ b/soft-fp/floatsihf.c
@@ -0,0 +1,45 @@
+/* Software floating-point emulation.
+   Convert a 32bit signed integer to IEEE half
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   In addition to the permissions in the GNU Lesser General Public
+   License, the Free Software Foundation gives you unlimited
+   permission to link the compiled version of this file into
+   combinations with other programs, and to distribute those
+   combinations without any restriction coming from the use of this
+   file.  (The Lesser General Public License restrictions do apply in
+   other respects; for example, they cover modification of the file,
+   and distribution when not linked into a combine executable.)
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "soft-fp.h"
+#include "half.h"
+
+HFtype
+__floatsihf (SItype i)
+{
+  FP_DECL_EX;
+  FP_DECL_H (A);
+  HFtype a;
+
+  FP_INIT_ROUNDMODE;
+  FP_FROM_INT_H (A, i, SI_BITS, USItype);
+  FP_PACK_RAW_H (a, A);
+  FP_HANDLE_EXCEPTIONS;
+
+  return a;
+}