[glibc/azanella/mips-hw-fp-round] mips: Implement truncf with hardware floating-point rounding instruction

[glibc/azanella/mips-hw-fp-round] mips: Implement truncf with hardware floating-point rounding instruction

[Adhemerval Zanella]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=8b3c945b3f5365834261f3e78225dabc441f467f

commit 8b3c945b3f5365834261f3e78225dabc441f467f
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date:   Wed Dec 27 10:03:06 2023 -0300

    mips: Implement truncf with hardware floating-point rounding instruction

Diff:
---
 sysdeps/mips/fpu/roundf_to_integer.h |  5 +++++
 sysdeps/mips/fpu/s_truncf.c          | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/sysdeps/mips/fpu/roundf_to_integer.h b/sysdeps/mips/fpu/roundf_to_integer.h
index 089322072e..f1a7fefda9 100644
--- a/sysdeps/mips/fpu/roundf_to_integer.h
+++ b/sysdeps/mips/fpu/roundf_to_integer.h
@@ -27,6 +27,7 @@ enum round_mode
 {
   CEIL,
   FLOOR,
+  TRUNC,
 };
 
 static inline float
@@ -47,6 +48,10 @@ round_to_integer_float (enum round_mode mode, float x)
   case FLOOR:
     asm ("floor.l.s %0, %0" : "+f" (r));
     break;
+  case TRUNC:
+    asm ("trunc.l.s %0, %0" : "+f" (r));
+    break;
+    break;
   }
   libc_fesetenvf (&fe);
 
diff --git a/sysdeps/mips/fpu/s_truncf.c b/sysdeps/mips/fpu/s_truncf.c
new file mode 100644
index 0000000000..f108c0e51f
--- /dev/null
+++ b/sysdeps/mips/fpu/s_truncf.c
@@ -0,0 +1,36 @@
+/* Round to integer, toward zero.  MIPS version.
+   Copyright (C) 2023 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.
+
+   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
+   <https://www.gnu.org/licenses/>.  */
+
+#if ((__mips_fpr == 64) \
+      && (__mips_hard_float == 1) \
+      && ((__mips == 32 && __mips_isa_rev > 1) || __mips == 64))
+
+#define NO_MATH_REDIRECT
+#include <math.h>
+#include <roundf_to_integer.h>
+#include <libm-alias-float.h>
+
+float
+__truncf (float x)
+{
+  return round_to_integer_float (TRUNC, x);
+}
+libm_alias_float (__trunc, trunc)
+#else
+# include <sysdeps/ieee754/flt-32/s_truncf.c>
+#endif