soft-fp: Add brain format support

In https://gcc.gnu.org/r13-3292 I've added brain format support
(std::bfloat16_t) on the GCC side, but as glibc has the master copy
of soft-fp, the following patch adds the files from that commit
and from https://gcc.gnu.org/r13-6598 and https://gcc.gnu.org/r13-6622
The files are not used by glibc right now.

1 files changed, 49 insertions, 0 deletions

diff --git a/soft-fp/extendbfsf2.c b/soft-fp/extendbfsf2.c
new file mode 100644
index 0000000000..dd1a20f81b
--- /dev/null
+++ b/soft-fp/extendbfsf2.c
@@ -0,0 +1,49 @@
+/* Software floating-point emulation.
+   Return an bfloat16 converted to IEEE single
+   Copyright (C) 2022-2024 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/>.  */
+
+#define FP_NO_EXACT_UNDERFLOW
+#include "soft-fp.h"
+#include "brain.h"
+#include "single.h"
+
+SFtype
+__extendbfsf2 (BFtype a)
+{
+  FP_DECL_EX;
+  FP_DECL_B (A);
+  FP_DECL_S (R);
+  SFtype r;
+
+  FP_INIT_EXCEPTIONS;
+  FP_UNPACK_RAW_B (A, a);
+  FP_EXTEND (S, B, 1, 1, R, A);
+  FP_PACK_RAW_S (r, R);
+  FP_HANDLE_EXCEPTIONS;
+
+  return r;
+}