diff --git a/newlib/libm/machine/riscv/Makefile.am b/newlib/libm/machine/riscv/Makefile.am
index 9443fb8e6..9e7b9e868 100644
--- a/newlib/libm/machine/riscv/Makefile.am
+++ b/newlib/libm/machine/riscv/Makefile.am
@@ -9,7 +9,8 @@ LIB_SOURCES = \
 	fesetexceptflag.c fesetround.c fetestexcept.c feupdateenv.c \
 	s_fma.c e_sqrt.c sf_fma.c ef_sqrt.c \
 	s_fmax.c s_fmin.c sf_fmax.c sf_fmin.c \
-	s_fabs.c sf_fabs.c
+	s_fabs.c sf_fabs.c \
+	s_fpclassify.c sf_fpclassify.c
 
 noinst_LIBRARIES = lib.a
 lib_a_SOURCES = $(LIB_SOURCES)
diff --git a/newlib/libm/machine/riscv/Makefile.in b/newlib/libm/machine/riscv/Makefile.in
index 063c643bb..5c915e90f 100644
--- a/newlib/libm/machine/riscv/Makefile.in
+++ b/newlib/libm/machine/riscv/Makefile.in
@@ -81,7 +81,8 @@ am__objects_1 = lib_a-feclearexcept.$(OBJEXT) \
 	lib_a-ef_sqrt.$(OBJEXT) lib_a-s_fmax.$(OBJEXT) \
 	lib_a-s_fmin.$(OBJEXT) lib_a-sf_fmax.$(OBJEXT) \
 	lib_a-sf_fmin.$(OBJEXT) lib_a-s_fabs.$(OBJEXT) \
-	lib_a-sf_fabs.$(OBJEXT)
+	lib_a-sf_fabs.$(OBJEXT) lib_a-s_fpclassify.$(OBJEXT) \
+	lib_a-sf_fpclassify.$(OBJEXT)
 am_lib_a_OBJECTS = $(am__objects_1)
 lib_a_OBJECTS = $(am_lib_a_OBJECTS)
 DEFAULT_INCLUDES = -I.@am__isrc@
@@ -212,7 +213,8 @@ LIB_SOURCES = \
 	fesetexceptflag.c fesetround.c fetestexcept.c feupdateenv.c \
 	s_fma.c e_sqrt.c sf_fma.c ef_sqrt.c \
 	s_fmax.c s_fmin.c sf_fmax.c sf_fmin.c \
-	s_fabs.c sf_fabs.c
+	s_fabs.c sf_fabs.c \
+	s_fpclassify.c sf_fpclassify.c
 
 noinst_LIBRARIES = lib.a
 lib_a_SOURCES = $(LIB_SOURCES)
@@ -422,6 +424,18 @@ lib_a-sf_fabs.o: sf_fabs.c
 lib_a-sf_fabs.obj: sf_fabs.c
 	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-sf_fabs.obj `if test -f 'sf_fabs.c'; then $(CYGPATH_W) 'sf_fabs.c'; else $(CYGPATH_W) '$(srcdir)/sf_fabs.c'; fi`
 
+lib_a-s_fpclassify.o: s_fpclassify.c
+	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-s_fpclassify.o `test -f 's_fpclassify.c' || echo '$(srcdir)/'`s_fpclassify.c
+
+lib_a-s_fpclassify.obj: s_fpclassify.c
+	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-s_fpclassify.obj `if test -f 's_fpclassify.c'; then $(CYGPATH_W) 's_fpclassify.c'; else $(CYGPATH_W) '$(srcdir)/s_fpclassify.c'; fi`
+
+lib_a-sf_fpclassify.o: sf_fpclassify.c
+	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-sf_fpclassify.o `test -f 'sf_fpclassify.c' || echo '$(srcdir)/'`sf_fpclassify.c
+
+lib_a-sf_fpclassify.obj: sf_fpclassify.c
+	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-sf_fpclassify.obj `if test -f 'sf_fpclassify.c'; then $(CYGPATH_W) 'sf_fpclassify.c'; else $(CYGPATH_W) '$(srcdir)/sf_fpclassify.c'; fi`
+
 ID: $(HEADERS) $(SOURCES) $(LISP) $(TAGS_FILES)
 	list='$(SOURCES) $(HEADERS) $(LISP) $(TAGS_FILES)'; \
 	unique=`for i in $$list; do \
diff --git a/newlib/libm/machine/riscv/riscv_math.h b/newlib/libm/machine/riscv/riscv_math.h
new file mode 100644
index 000000000..38948ca12
--- /dev/null
+++ b/newlib/libm/machine/riscv/riscv_math.h
@@ -0,0 +1,80 @@
+/*
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 2020 Kito Cheng
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ *    copyright notice, this list of conditions and the following
+ *    disclaimer in the documentation and/or other materials provided
+ *    with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __RISCV_MATH_H
+#define __RISCV_MATH_H
+
+
+
+#ifdef __riscv_flen
+
+#define FCLASS_NEG_INF       (1 << 0)
+#define FCLASS_NEG_NORMAL    (1 << 1)
+#define FCLASS_NEG_SUBNORMAL (1 << 2)
+#define FCLASS_NEG_ZERO      (1 << 3)
+#define FCLASS_POS_ZERO      (1 << 4)
+#define FCLASS_POS_SUBNORMAL (1 << 5)
+#define FCLASS_POS_NORMAL    (1 << 6)
+#define FCLASS_POS_INF       (1 << 7)
+#define FCLASS_SNAN          (1 << 8)
+#define FCLASS_QNAN          (1 << 9)
+
+
+#define FCLASS_INF           (FCLASS_NEG_INF | FCLASS_POS_INF)
+#define FCLASS_ZERO          (FCLASS_NEG_ZERO | FCLASS_POS_ZERO)
+#define FCLASS_NORMAL        (FCLASS_NEG_NORMAL | FCLASS_POS_NORMAL)
+#define FCLASS_SUBNORMAL     (FCLASS_NEG_SUBNORMAL | FCLASS_POS_SUBNORMAL)
+#define FCLASS_NAN           (FCLASS_SNAN | FCLASS_QNAN)
+
+#if __riscv_flen >= 64
+static inline long _fclass_d(double x){
+  long fclass;
+  __asm __volatile ("fclass.d\t%0, %1" : "=r" (fclass) : "f" (x));
+  return fclass;
+}
+#endif
+
+#if __riscv_flen >= 32
+static inline long _fclass_f(float x){
+  long fclass;
+  __asm __volatile ("fclass.s\t%0, %1" : "=r" (fclass) : "f" (x));
+  return fclass;
+}
+#endif
+
+#endif /* __riscv_flen */
+
+
+#endif /* __RISCV_MATH_H */
diff --git a/newlib/libm/machine/riscv/s_finite.c b/newlib/libm/machine/riscv/s_finite.c
new file mode 100644
index 000000000..f5336e5dc
--- /dev/null
+++ b/newlib/libm/machine/riscv/s_finite.c
@@ -0,0 +1,51 @@
+/*
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 2020 Kito Cheng
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ *    copyright notice, this list of conditions and the following
+ *    disclaimer in the documentation and/or other materials provided
+ *    with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * finite(x) returns 1 is x is finite, else 0;
+ */
+
+#include <math.h>
+
+#if defined(__riscv_flen) && __riscv_flen >= 64
+#include "riscv_math.h"
+int finite(double x)
+{
+	long fclass = _fclass_d (x);
+	return (fclass & FCLASS_INF) == 0;
+}
+#else
+#include "../../common/s_finite.c"
+#endif
diff --git a/newlib/libm/machine/riscv/s_fpclassify.c b/newlib/libm/machine/riscv/s_fpclassify.c
new file mode 100644
index 000000000..8112d4f78
--- /dev/null
+++ b/newlib/libm/machine/riscv/s_fpclassify.c
@@ -0,0 +1,60 @@
+/*
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 2020 Kito Cheng
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ *    copyright notice, this list of conditions and the following
+ *    disclaimer in the documentation and/or other materials provided
+ *    with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <math.h>
+
+#if defined(__riscv_flen) && __riscv_flen >= 64
+
+#include "riscv_math.h"
+
+int
+__fpclassifyd (double x)
+{
+  long fclass = _fclass_d (x);
+
+  if (fclass & FCLASS_ZERO)
+    return FP_ZERO;
+  else if (fclass & FCLASS_NORMAL)
+    return FP_NORMAL;
+  else if (fclass & FCLASS_SUBNORMAL)
+    return FP_SUBNORMAL;
+  else if (fclass & FCLASS_INF)
+    return FP_INFINITE;
+  else
+    return FP_NAN;
+}
+
+#else
+#include "../../common/s_fpclassify.c"
+#endif
diff --git a/newlib/libm/machine/riscv/s_isinf.c b/newlib/libm/machine/riscv/s_isinf.c
new file mode 100644
index 000000000..3c82ee268
--- /dev/null
+++ b/newlib/libm/machine/riscv/s_isinf.c
@@ -0,0 +1,52 @@
+/*
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 2020 Kito Cheng
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ *    copyright notice, this list of conditions and the following
+ *    disclaimer in the documentation and/or other materials provided
+ *    with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <math.h>
+#include <ieeefp.h>
+
+#if defined(__riscv_flen) && __riscv_flen >= 64
+
+#include "riscv_math.h"
+#undef isinf
+
+int
+isinf (double x)
+{
+	long fclass = _fclass_d (x);
+	return (fclass & FCLASS_INF);
+}
+#else
+#include "../../common/sf_isinf.c"
+#endif
diff --git a/newlib/libm/machine/riscv/sf_finite.c b/newlib/libm/machine/riscv/sf_finite.c
new file mode 100644
index 000000000..f1cf5c6ce
--- /dev/null
+++ b/newlib/libm/machine/riscv/sf_finite.c
@@ -0,0 +1,48 @@
+/*
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 2020 Kito Cheng
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ *    copyright notice, this list of conditions and the following
+ *    disclaimer in the documentation and/or other materials provided
+ *    with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <math.h>
+
+#if defined(__riscv_flen) && __riscv_flen >= 32
+
+#include "riscv_math.h"
+int finitef(float x)
+{
+	long fclass = _fclass_f (x);
+	return (fclass & FCLASS_INF) == 0;
+}
+#else
+#include "../../common/sf_finite.c"
+#endif
diff --git a/newlib/libm/machine/riscv/sf_fpclassify.c b/newlib/libm/machine/riscv/sf_fpclassify.c
new file mode 100644
index 000000000..dee9a7a25
--- /dev/null
+++ b/newlib/libm/machine/riscv/sf_fpclassify.c
@@ -0,0 +1,60 @@
+/*
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 2020 Kito Cheng
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ *    copyright notice, this list of conditions and the following
+ *    disclaimer in the documentation and/or other materials provided
+ *    with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <math.h>
+
+#if defined(__riscv_flen) && __riscv_flen >= 32
+
+#include "riscv_math.h"
+
+int
+__fpclassifyf (float x)
+{
+  long fclass = _fclass_f (x);
+
+  if (fclass & FCLASS_ZERO)
+    return FP_ZERO;
+  else if (fclass & FCLASS_NORMAL)
+    return FP_NORMAL;
+  else if (fclass & FCLASS_SUBNORMAL)
+    return FP_SUBNORMAL;
+  else if (fclass & FCLASS_INF)
+    return FP_INFINITE;
+  else
+    return FP_NAN;
+}
+
+#else
+#include "../../common/sf_fpclassify.c"
+#endif
diff --git a/newlib/libm/machine/riscv/sf_isinf.c b/newlib/libm/machine/riscv/sf_isinf.c
new file mode 100644
index 000000000..0c60f33af
--- /dev/null
+++ b/newlib/libm/machine/riscv/sf_isinf.c
@@ -0,0 +1,52 @@
+/*
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 2020 Kito Cheng
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ *    copyright notice, this list of conditions and the following
+ *    disclaimer in the documentation and/or other materials provided
+ *    with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <math.h>
+#include <ieeefp.h>
+
+#if defined(__riscv_flen) && __riscv_flen >= 32
+
+#include "riscv_math.h"
+#undef isinff
+
+int
+isinff (float x)
+{
+	long fclass = _fclass_f (x);
+	return (fclass & FCLASS_INF);
+}
+#else
+#include "../../common/sf_isinf.c"
+#endif