RISC-V: Hard Float Support

This patch contains hardware floating-point support for the RISC-V ISA.
While we currently only support hard-float systems with both the F and D
extensions, I've left the F-specific code split out into seperate
folders in order to ease adding support for F-only and RV32I-based
systems in the future.  I gave this a quick once-over and believe I've
removed all the code that implements RV32IF, RV32IFD, and RV64IF
targets.

2018-01-29  Palmer Dabbelt  <palmer@sifive.com>

        * sysdeps/riscv/rv64/rvd/s_ceil.c: New file.
        * sysdeps/riscv/rv64/rvd/s_floor.c: Likewise.
        * sysdeps/riscv/rv64/rvd/s_llrint.c: Likewise.
        * sysdeps/riscv/rv64/rvd/s_llround.c: Likewise.
        * sysdeps/riscv/rv64/rvd/s_lrint.c: Likewise.
        * sysdeps/riscv/rv64/rvd/s_lround.c: Likewise.
        * sysdeps/riscv/rv64/rvd/s_nearbyint.c: Likewise.
        * sysdeps/riscv/rv64/rvd/s_rint.c: Likewise.
        * sysdeps/riscv/rv64/rvd/s_round.c: Likewise.
        * sysdeps/riscv/rv64/rvd/s_roundeven.c: Likewise.
        * sysdeps/riscv/rv64/rvd/s_trunc.c: Likewise.
        * sysdeps/riscv/rv64/rvf/s_llrintf.c: Likewise.
        * sysdeps/riscv/rv64/rvf/s_llroundf.c: Likewise.
        * sysdeps/riscv/rv64/rvf/s_lrintf.c: Likewise.
        * sysdeps/riscv/rv64/rvf/s_lroundf.c: Likewise.
        * sysdeps/riscv/rvd/e_sqrt.c: Likewise.
        * sysdeps/riscv/rvd/s_copysign.c: Likewise.
        * sysdeps/riscv/rvd/s_finite.c: Likewise.
        * sysdeps/riscv/rvd/s_fma.c: Likewise.
        * sysdeps/riscv/rvd/s_fmax.c: Likewise.
        * sysdeps/riscv/rvd/s_fmin.c: Likewise.
        * sysdeps/riscv/rvd/s_fpclassify.c: Likewise.
        * sysdeps/riscv/rvd/s_isinf.c: Likewise.
        * sysdeps/riscv/rvd/s_isnan.c: Likewise.
        * sysdeps/riscv/rvd/s_issignaling.c: Likewise.
        * sysdeps/riscv/rvf/e_sqrtf.c: Likewise.
        * sysdeps/riscv/rvf/fclrexcpt.c: Likewise.
        * sysdeps/riscv/rvf/fegetenv.c: Likewise.
        * sysdeps/riscv/rvf/fegetmode.c: Likewise.
        * sysdeps/riscv/rvf/fegetround.c: Likewise.
        * sysdeps/riscv/rvf/feholdexcpt.c: Likewise.
        * sysdeps/riscv/rvf/fesetenv.c: Likewise.
        * sysdeps/riscv/rvf/fesetexcept.c: Likewise.
        * sysdeps/riscv/rvf/fesetmode.c: Likewise.
        * sysdeps/riscv/rvf/fesetround.c: Likewise.
        * sysdeps/riscv/rvf/feupdateenv.c: Likewise.
        * sysdeps/riscv/rvf/fgetexcptflg.c: Likewise.
        * sysdeps/riscv/rvf/fraiseexcpt.c: Likewise.
        * sysdeps/riscv/rvf/fsetexcptflg.c: Likewise.
        * sysdeps/riscv/rvf/ftestexcept.c: Likewise.
        * sysdeps/riscv/rvf/get-rounding-mode.h: Likewise.
        * sysdeps/riscv/rvf/math_private.h: Likewise.
        * sysdeps/riscv/rvf/s_ceilf.c: Likewise.
        * sysdeps/riscv/rvf/s_copysignf.c: Likewise.
        * sysdeps/riscv/rvf/s_finitef.c: Likewise.
        * sysdeps/riscv/rvf/s_floorf.c: Likewise.
        * sysdeps/riscv/rvf/s_fmaf.c: Likewise.
        * sysdeps/riscv/rvf/s_fmaxf.c: Likewise.
        * sysdeps/riscv/rvf/s_fminf.c: Likewise.
        * sysdeps/riscv/rvf/s_fpclassifyf.c: Likewise.
        * sysdeps/riscv/rvf/s_isinff.c: Likewise.
        * sysdeps/riscv/rvf/s_isnanf.c: Likewise.
        * sysdeps/riscv/rvf/s_issignalingf.c: Likewise.
        * sysdeps/riscv/rvf/s_nearbyintf.c: Likewise.
        * sysdeps/riscv/rvf/s_rintf.c: Likewise.
        * sysdeps/riscv/rvf/s_roundevenf.c: Likewise.
        * sysdeps/riscv/rvf/s_roundf.c: Likewise.
        * sysdeps/riscv/rvf/s_truncf.c: Likewise.

33 files changed, 1265 insertions, 0 deletions

diff --git a/sysdeps/riscv/rvf/e_sqrtf.c b/sysdeps/riscv/rvf/e_sqrtf.c
new file mode 100644
index 0000000000..711d93e430
--- /dev/null
+++ b/sysdeps/riscv/rvf/e_sqrtf.c
@@ -0,0 +1,27 @@
+/* Single precision floating point square root.  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+
+float
+__ieee754_sqrtf (float x)
+{
+  asm ("fsqrt.s %0, %1" : "=f" (x) : "f" (x));
+  return x;
+}
+strong_alias (__ieee754_sqrtf, __sqrtf_finite)
diff --git a/sysdeps/riscv/rvf/fclrexcpt.c b/sysdeps/riscv/rvf/fclrexcpt.c
new file mode 100644
index 0000000000..bdad377e88
--- /dev/null
+++ b/sysdeps/riscv/rvf/fclrexcpt.c
@@ -0,0 +1,28 @@
+/* Clear given exceptions in current floating-point environment.
+   Copyright (C) 1998-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+feclearexcept (int excepts)
+{
+  asm volatile ("csrc fflags, %0" : : "r" (excepts));
+  return 0;
+}
+libm_hidden_def (feclearexcept)
diff --git a/sysdeps/riscv/rvf/fegetenv.c b/sysdeps/riscv/rvf/fegetenv.c
new file mode 100644
index 0000000000..1c29413be5
--- /dev/null
+++ b/sysdeps/riscv/rvf/fegetenv.c
@@ -0,0 +1,32 @@
+/* Store current floating-point environment.
+   Copyright (C) 1998-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+__fegetenv (fenv_t *envp)
+{
+  _FPU_GETCW (*envp);
+
+  /* Success.  */
+  return 0;
+}
+libm_hidden_def (__fegetenv)
+weak_alias (__fegetenv, fegetenv)
+libm_hidden_weak (fegetenv)
diff --git a/sysdeps/riscv/rvf/fegetmode.c b/sysdeps/riscv/rvf/fegetmode.c
new file mode 100644
index 0000000000..67ae14c4ff
--- /dev/null
+++ b/sysdeps/riscv/rvf/fegetmode.c
@@ -0,0 +1,27 @@
+/* Store current floating-point control modes.  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+fegetmode (femode_t *modep)
+{
+  _FPU_GETCW (*modep);
+  return 0;
+}
diff --git a/sysdeps/riscv/rvf/fegetround.c b/sysdeps/riscv/rvf/fegetround.c
new file mode 100644
index 0000000000..f7692a827b
--- /dev/null
+++ b/sysdeps/riscv/rvf/fegetround.c
@@ -0,0 +1,29 @@
+/* Return current rounding direction.
+   Copyright (C) 1998-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <math_private.h>
+
+int
+__fegetround (void)
+{
+  return riscv_getround ();
+}
+libm_hidden_def (__fegetround)
+weak_alias (__fegetround, fegetround)
+libm_hidden_weak (fegetround)
diff --git a/sysdeps/riscv/rvf/feholdexcpt.c b/sysdeps/riscv/rvf/feholdexcpt.c
new file mode 100644
index 0000000000..ea9060f3dc
--- /dev/null
+++ b/sysdeps/riscv/rvf/feholdexcpt.c
@@ -0,0 +1,30 @@
+/* Store current floating-point environment and clear exceptions.
+   Copyright (C) 2000-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <math_private.h>
+
+int
+__feholdexcept (fenv_t *envp)
+{
+  libc_feholdexcept_riscv (envp);
+  return 0;
+}
+libm_hidden_def (__feholdexcept)
+weak_alias (__feholdexcept, feholdexcept)
+libm_hidden_weak (feholdexcept)
diff --git a/sysdeps/riscv/rvf/fesetenv.c b/sysdeps/riscv/rvf/fesetenv.c
new file mode 100644
index 0000000000..5d02d80101
--- /dev/null
+++ b/sysdeps/riscv/rvf/fesetenv.c
@@ -0,0 +1,30 @@
+/* Install given floating-point environment.
+   Copyright (C) 1998-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <math_private.h>
+
+int
+__fesetenv (const fenv_t *envp)
+{
+  libc_fesetenv_riscv (envp);
+  return 0;
+}
+libm_hidden_def (__fesetenv)
+weak_alias (__fesetenv, fesetenv)
+libm_hidden_weak (fesetenv)
diff --git a/sysdeps/riscv/rvf/fesetexcept.c b/sysdeps/riscv/rvf/fesetexcept.c
new file mode 100644
index 0000000000..70059aa61a
--- /dev/null
+++ b/sysdeps/riscv/rvf/fesetexcept.c
@@ -0,0 +1,26 @@
+/* Set given exception flags.  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+
+int
+fesetexcept (int excepts)
+{
+  asm volatile ("csrs fflags, %0" : : "r" (excepts));
+  return 0;
+}
diff --git a/sysdeps/riscv/rvf/fesetmode.c b/sysdeps/riscv/rvf/fesetmode.c
new file mode 100644
index 0000000000..d39c5626fe
--- /dev/null
+++ b/sysdeps/riscv/rvf/fesetmode.c
@@ -0,0 +1,31 @@
+/* Install given floating-point control modes.  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+fesetmode (const femode_t *modep)
+{
+  asm volatile ("csrc fcsr, %0" : : "r" (~FE_ALL_EXCEPT));
+
+  if (modep != FE_DFL_MODE)
+    asm volatile ("csrs fcsr, %0" : : "r" (*modep & ~FE_ALL_EXCEPT));
+
+  return 0;
+}
diff --git a/sysdeps/riscv/rvf/fesetround.c b/sysdeps/riscv/rvf/fesetround.c
new file mode 100644
index 0000000000..bf705ef0c9
--- /dev/null
+++ b/sysdeps/riscv/rvf/fesetround.c
@@ -0,0 +1,39 @@
+/* Set current rounding direction.
+   Copyright (C) 1998-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <math_private.h>
+
+int
+__fesetround (int round)
+{
+  switch (round)
+    {
+    case FE_TONEAREST:
+    case FE_TOWARDZERO:
+    case FE_DOWNWARD:
+    case FE_UPWARD:
+      riscv_setround (round);
+      return 0;
+    default:
+      return round; /* A nonzero value.  */
+    }
+}
+libm_hidden_def (__fesetround)
+weak_alias (__fesetround, fesetround)
+libm_hidden_weak (fesetround)
diff --git a/sysdeps/riscv/rvf/feupdateenv.c b/sysdeps/riscv/rvf/feupdateenv.c
new file mode 100644
index 0000000000..133d7eca11
--- /dev/null
+++ b/sysdeps/riscv/rvf/feupdateenv.c
@@ -0,0 +1,30 @@
+/* Install given floating-point environment and raise exceptions.
+   Copyright (C) 1998-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <math_private.h>
+
+int
+__feupdateenv (const fenv_t *envp)
+{
+  libc_feupdateenv_riscv (envp);
+  return 0;
+}
+libm_hidden_def (__feupdateenv)
+weak_alias (__feupdateenv, feupdateenv)
+libm_hidden_weak (feupdateenv)
diff --git a/sysdeps/riscv/rvf/fgetexcptflg.c b/sysdeps/riscv/rvf/fgetexcptflg.c
new file mode 100644
index 0000000000..367f0135d4
--- /dev/null
+++ b/sysdeps/riscv/rvf/fgetexcptflg.c
@@ -0,0 +1,30 @@
+/* Store current representation for exceptions.
+   Copyright (C) 1998-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <math_private.h>
+
+int
+fegetexceptflag (fexcept_t *flagp, int excepts)
+{
+  /* Get the current exceptions.  */
+  *flagp = riscv_getflags () & excepts;
+
+  /* Success.  */
+  return 0;
+}
diff --git a/sysdeps/riscv/rvf/fraiseexcpt.c b/sysdeps/riscv/rvf/fraiseexcpt.c
new file mode 100644
index 0000000000..dee90c3476
--- /dev/null
+++ b/sysdeps/riscv/rvf/fraiseexcpt.c
@@ -0,0 +1,30 @@
+/* Raise given exceptions.
+   Copyright (C) 2000-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+__feraiseexcept (int excepts)
+{
+  asm volatile ("csrs fflags, %0" : : "r" (excepts));
+  return 0;
+}
+libm_hidden_def (__feraiseexcept)
+weak_alias (__feraiseexcept, feraiseexcept)
+libm_hidden_weak (feraiseexcept)
diff --git a/sysdeps/riscv/rvf/fsetexcptflg.c b/sysdeps/riscv/rvf/fsetexcptflg.c
new file mode 100644
index 0000000000..9e5bebf289
--- /dev/null
+++ b/sysdeps/riscv/rvf/fsetexcptflg.c
@@ -0,0 +1,30 @@
+/* Set floating-point environment exception handling.
+   Copyright (C) 1998-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+fesetexceptflag (const fexcept_t *flagp, int excepts)
+{
+  fexcept_t flags = *flagp;
+  asm volatile ("csrc fflags, %0" : : "r" (excepts));
+  asm volatile ("csrs fflags, %0" : : "r" (flags & excepts));
+
+  return 0;
+}
diff --git a/sysdeps/riscv/rvf/ftestexcept.c b/sysdeps/riscv/rvf/ftestexcept.c
new file mode 100644
index 0000000000..a248bd6319
--- /dev/null
+++ b/sysdeps/riscv/rvf/ftestexcept.c
@@ -0,0 +1,27 @@
+/* Test exception in current environment.
+   Copyright (C) 1998-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+#include <math_private.h>
+
+int
+fetestexcept (int excepts)
+{
+  return libc_fetestexcept_riscv (excepts);
+}
+libm_hidden_def (fetestexcept)
diff --git a/sysdeps/riscv/rvf/get-rounding-mode.h b/sysdeps/riscv/rvf/get-rounding-mode.h
new file mode 100644
index 0000000000..42891324dd
--- /dev/null
+++ b/sysdeps/riscv/rvf/get-rounding-mode.h
@@ -0,0 +1,32 @@
+/* Determine floating-point rounding mode within libc.  RISC-V version.
+   Copyright (C) 2015-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _RISCV_GET_ROUNDING_MODE_H
+#define _RISCV_GET_ROUNDING_MODE_H
+
+/* Return the floating-point rounding mode.  */
+
+static inline int
+get_rounding_mode (void)
+{
+  int rm;
+  asm volatile ("frrm %0" : "=r" (rm));
+  return rm;
+}
+
+#endif /* get-rounding-mode.h */
diff --git a/sysdeps/riscv/rvf/math_private.h b/sysdeps/riscv/rvf/math_private.h
new file mode 100644
index 0000000000..cdb7858fc8
--- /dev/null
+++ b/sysdeps/riscv/rvf/math_private.h
@@ -0,0 +1,161 @@
+/* Private floating point rounding and exceptions handling.  RISC-V version.
+   Copyright (C) 2014-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef RISCV_MATH_PRIVATE_H
+#define RISCV_MATH_PRIVATE_H 1
+
+#include <fenv.h>
+#include <fpu_control.h>
+#include <get-rounding-mode.h>
+
+static __always_inline int
+riscv_getround (void)
+{
+  return get_rounding_mode ();
+}
+
+static __always_inline void
+riscv_setround (int rm)
+{
+  asm volatile ("fsrm %z0" : : "rJ" (rm));
+}
+
+static __always_inline int
+riscv_getflags (void)
+{
+  int flags;
+  asm volatile ("frflags %0" : "=r" (flags));
+  return flags;
+}
+
+static __always_inline void
+riscv_setflags (int flags)
+{
+  asm volatile ("fsflags %z0" : : "rJ" (flags));
+}
+
+static __always_inline void
+libc_feholdexcept_riscv (fenv_t *envp)
+{
+  asm volatile ("csrrc %0, fcsr, %1" : "=r" (*envp) : "i" (FE_ALL_EXCEPT));
+}
+
+#define libc_feholdexcept  libc_feholdexcept_riscv
+#define libc_feholdexceptf libc_feholdexcept_riscv
+#define libc_feholdexceptl libc_feholdexcept_riscv
+
+static __always_inline void
+libc_fesetround_riscv (int round)
+{
+  riscv_setround (round);
+}
+
+#define libc_fesetround  libc_fesetround_riscv
+#define libc_fesetroundf libc_fesetround_riscv
+#define libc_fesetroundl libc_fesetround_riscv
+
+static __always_inline void
+libc_feholdexcept_setround_riscv (fenv_t *envp, int round)
+{
+  libc_fesetround_riscv (round);
+  libc_feholdexcept_riscv (envp);
+}
+
+#define libc_feholdexcept_setround  libc_feholdexcept_setround_riscv
+#define libc_feholdexcept_setroundf libc_feholdexcept_setround_riscv
+#define libc_feholdexcept_setroundl libc_feholdexcept_setround_riscv
+
+static __always_inline int
+libc_fetestexcept_riscv (int ex)
+{
+  return riscv_getflags () & ex;
+}
+
+#define libc_fetestexcept  libc_fetestexcept_riscv
+#define libc_fetestexceptf libc_fetestexcept_riscv
+#define libc_fetestexceptl libc_fetestexcept_riscv
+
+static __always_inline void
+libc_fesetenv_riscv (const fenv_t *envp)
+{
+  long int env = (long int) envp - (long int) FE_DFL_ENV;
+  if (env != 0)
+    env = *envp;
+
+  _FPU_SETCW (env);
+}
+
+#define libc_fesetenv  libc_fesetenv_riscv
+#define libc_fesetenvf libc_fesetenv_riscv
+#define libc_fesetenvl libc_fesetenv_riscv
+#define libc_feresetround_noex  libc_fesetenv_riscv
+#define libc_feresetround_noexf libc_fesetenv_riscv
+#define libc_feresetround_noexl libc_fesetenv_riscv
+
+static __always_inline int
+libc_feupdateenv_test_riscv (const fenv_t *envp, int ex)
+{
+  fenv_t env = *envp;
+  int flags = riscv_getflags ();
+  asm volatile ("csrw fcsr, %z0" : : "rJ" (env | flags));
+  return flags & ex;
+}
+
+#define libc_feupdateenv_test  libc_feupdateenv_test_riscv
+#define libc_feupdateenv_testf libc_feupdateenv_test_riscv
+#define libc_feupdateenv_testl libc_feupdateenv_test_riscv
+
+static __always_inline void
+libc_feupdateenv_riscv (const fenv_t *envp)
+{
+  _FPU_SETCW (*envp | riscv_getflags ());
+}
+
+#define libc_feupdateenv  libc_feupdateenv_riscv
+#define libc_feupdateenvf libc_feupdateenv_riscv
+#define libc_feupdateenvl libc_feupdateenv_riscv
+
+static __always_inline void
+libc_feholdsetround_riscv (fenv_t *envp, int round)
+{
+  /* Note this implementation makes an improperly-formatted fenv_t and
+     so should only be used in conjunction with libc_feresetround.  */
+  int old_round;
+  asm volatile ("csrrw %0, frm, %z1" : "=r" (old_round) : "rJ" (round));
+  *envp = old_round;
+}
+
+#define libc_feholdsetround  libc_feholdsetround_riscv
+#define libc_feholdsetroundf libc_feholdsetround_riscv
+#define libc_feholdsetroundl libc_feholdsetround_riscv
+
+static __always_inline void
+libc_feresetround_riscv (fenv_t *envp)
+{
+  /* Note this implementation takes an improperly-formatted fenv_t and
+     so should only be used in conjunction with libc_feholdsetround.  */
+  riscv_setround (*envp);
+}
+
+#define libc_feresetround  libc_feresetround_riscv
+#define libc_feresetroundf libc_feresetround_riscv
+#define libc_feresetroundl libc_feresetround_riscv
+
+#include_next <math_private.h>
+
+#endif
diff --git a/sysdeps/riscv/rvf/s_ceilf.c b/sysdeps/riscv/rvf/s_ceilf.c
new file mode 100644
index 0000000000..d7e291acf8
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_ceilf.c
@@ -0,0 +1,52 @@
+/* ceilf().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <math_private.h>
+#include <libm-alias-float.h>
+#include <stdint.h>
+
+float
+__ceilf (float x)
+{
+  int flags = riscv_getflags ();
+  bool nan = isnan (x);
+  float mag = fabsf (x);
+
+  if (nan)
+    return x + x;
+
+  if (mag < (1 << __FLT_MANT_DIG__))
+    {
+      int32_t i;
+      float new_x;
+
+      asm volatile ("fcvt.w.s %0, %1, rup" : "=r" (i) : "f" (x));
+      asm volatile ("fcvt.s.w %0, %1, rup" : "=f" (new_x) : "r" (i));
+
+      /* ceil(-0) == -0, and in general we'll always have the same
+	 sign as our input.  */
+      x = copysignf (new_x, x);
+
+      riscv_setflags (flags);
+    }
+
+  return x;
+}
+
+libm_alias_float (__ceil, ceil)
diff --git a/sysdeps/riscv/rvf/s_copysignf.c b/sysdeps/riscv/rvf/s_copysignf.c
new file mode 100644
index 0000000000..4d1c122f7e
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_copysignf.c
@@ -0,0 +1,28 @@
+/* copysignf().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <libm-alias-float.h>
+
+float
+__copysignf (float x, float y)
+{
+  asm ("fsgnj.s %0, %1, %2" : "=f" (x) : "f" (x), "f" (y));
+  return x;
+}
+libm_alias_float (__copysign, copysign)
diff --git a/sysdeps/riscv/rvf/s_finitef.c b/sysdeps/riscv/rvf/s_finitef.c
new file mode 100644
index 0000000000..04ce08719b
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_finitef.c
@@ -0,0 +1,28 @@
+/* finitef().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <math_private.h>
+
+int
+__finitef (float x)
+{
+  return _FCLASS (x) & ~(_FCLASS_INF | _FCLASS_NAN);
+}
+hidden_def (__finitef)
+weak_alias (__finitef, finitef)
diff --git a/sysdeps/riscv/rvf/s_floorf.c b/sysdeps/riscv/rvf/s_floorf.c
new file mode 100644
index 0000000000..3c9c625e2f
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_floorf.c
@@ -0,0 +1,52 @@
+/* floorf().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <math_private.h>
+#include <libm-alias-float.h>
+#include <stdint.h>
+
+float
+__floorf (float x)
+{
+  int flags = riscv_getflags ();
+  bool nan = isnan (x);
+  float mag = fabsf (x);
+
+  if (nan)
+    return x + x;
+
+  if (mag < (1 << __FLT_MANT_DIG__))
+    {
+      int32_t i;
+      float new_x;
+
+      asm volatile ("fcvt.w.s %0, %1, rdn" : "=r" (i) : "f" (x));
+      asm volatile ("fcvt.s.w %0, %1, rdn" : "=f" (new_x) : "r" (i));
+
+      /* floor(-0) == -0, and in general we'll always have the same
+	 sign as our input.  */
+      x = copysignf (new_x, x);
+
+      riscv_setflags (flags);
+    }
+
+  return x;
+}
+
+libm_alias_float (__floor, floor)
diff --git a/sysdeps/riscv/rvf/s_fmaf.c b/sysdeps/riscv/rvf/s_fmaf.c
new file mode 100644
index 0000000000..946e7ed0c9
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_fmaf.c
@@ -0,0 +1,30 @@
+/* fmaf().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <fenv.h>
+#include <ieee754.h>
+#include <libm-alias-float.h>
+
+float
+__fmaf (float x, float y, float z)
+{
+  asm ("fmadd.s %0, %1, %2, %3" : "=f" (x) : "f" (x), "f" (y), "f" (z));
+  return x;
+}
+libm_alias_float (__fma, fma)
diff --git a/sysdeps/riscv/rvf/s_fmaxf.c b/sysdeps/riscv/rvf/s_fmaxf.c
new file mode 100644
index 0000000000..3293f2f41c
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_fmaxf.c
@@ -0,0 +1,28 @@
+/* fmaxf().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <libm-alias-float.h>
+
+float
+__fmaxf (float x, float y)
+{
+  asm ("fmax.s %0, %1, %2" : "=f" (x) : "f" (x), "f" (y));
+  return x;
+}
+libm_alias_float (__fmax, fmax)
diff --git a/sysdeps/riscv/rvf/s_fminf.c b/sysdeps/riscv/rvf/s_fminf.c
new file mode 100644
index 0000000000..e4411f04b2
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_fminf.c
@@ -0,0 +1,28 @@
+/* fminf().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <libm-alias-float.h>
+
+float
+__fminf (float x, float y)
+{
+  asm ("fmin.s %0, %1, %2" : "=f" (x) : "f" (x), "f" (y));
+  return x;
+}
+libm_alias_float (__fmin, fmin)
diff --git a/sysdeps/riscv/rvf/s_fpclassifyf.c b/sysdeps/riscv/rvf/s_fpclassifyf.c
new file mode 100644
index 0000000000..4abcf3edac
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_fpclassifyf.c
@@ -0,0 +1,36 @@
+/* fpclassifyf().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <math_private.h>
+
+int
+__fpclassifyf (float x)
+{
+  int cls = _FCLASS (x);
+  if (__builtin_expect (cls & _FCLASS_NORM, _FCLASS_NORM))
+    return FP_NORMAL;
+  if (__builtin_expect (cls & _FCLASS_ZERO, _FCLASS_ZERO))
+    return FP_ZERO;
+  if (__builtin_expect (cls & _FCLASS_SUBNORM, _FCLASS_SUBNORM))
+    return FP_SUBNORMAL;
+  if (__builtin_expect (cls & _FCLASS_INF, _FCLASS_INF))
+    return FP_INFINITE;
+  return FP_NAN;
+}
+libm_hidden_def (__fpclassifyf)
diff --git a/sysdeps/riscv/rvf/s_isinff.c b/sysdeps/riscv/rvf/s_isinff.c
new file mode 100644
index 0000000000..1c7413190c
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_isinff.c
@@ -0,0 +1,29 @@
+/* isinff().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <math_private.h>
+
+int
+__isinff (float x)
+{
+  int cls = _FCLASS (x);
+  return -((cls & _FCLASS_MINF) ? 1 : 0) | ((cls & _FCLASS_PINF) ? 1 : 0);
+}
+hidden_def (__isinff)
+weak_alias (__isinff, isinff)
diff --git a/sysdeps/riscv/rvf/s_isnanf.c b/sysdeps/riscv/rvf/s_isnanf.c
new file mode 100644
index 0000000000..30a88bb23c
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_isnanf.c
@@ -0,0 +1,28 @@
+/* isnanf().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <math_private.h>
+
+int
+__isnanf (float x)
+{
+  return (_FCLASS (x) & _FCLASS_NAN) != 0;
+}
+hidden_def (__isnanf)
+weak_alias (__isnanf, isnanf)
diff --git a/sysdeps/riscv/rvf/s_issignalingf.c b/sysdeps/riscv/rvf/s_issignalingf.c
new file mode 100644
index 0000000000..e67efc794b
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_issignalingf.c
@@ -0,0 +1,27 @@
+/* issignalingf().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <math_private.h>
+
+int
+__issignalingf (float x)
+{
+  return (_FCLASS (x) & _FCLASS_SNAN) != 0;
+}
+libm_hidden_def (__issignalingf)
diff --git a/sysdeps/riscv/rvf/s_nearbyintf.c b/sysdeps/riscv/rvf/s_nearbyintf.c
new file mode 100644
index 0000000000..d653794d71
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_nearbyintf.c
@@ -0,0 +1,52 @@
+/* Round to int floating-point values.  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <math_private.h>
+#include <libm-alias-float.h>
+#include <stdint.h>
+
+float
+__nearbyintf (float x)
+{
+  int flags = riscv_getflags ();
+  bool nan = isnan (x);
+  float mag = fabsf (x);
+
+  if (nan)
+    return x + x;
+
+  if (mag < (1 << __FLT_MANT_DIG__))
+    {
+      int32_t i;
+      float new_x;
+
+      asm volatile ("fcvt.w.s %0, %1" : "=r" (i) : "f" (x));
+      asm volatile ("fcvt.s.w %0, %1" : "=f" (new_x) : "r" (i));
+
+      /* nearbyint(-0) == -0, and in general we'll always have the same
+	 sign as our input.  */
+      x = copysignf (new_x, x);
+
+      riscv_setflags (flags);
+    }
+
+  return x;
+}
+
+libm_alias_float (__nearbyint, nearbyint)
diff --git a/sysdeps/riscv/rvf/s_rintf.c b/sysdeps/riscv/rvf/s_rintf.c
new file mode 100644
index 0000000000..2ec3877a4f
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_rintf.c
@@ -0,0 +1,52 @@
+/* rintf().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <math_private.h>
+#include <libm-alias-float.h>
+#include <stdint.h>
+
+float
+__rintf (float x)
+{
+  bool nan;
+  float mag;
+
+  nan = isnan (x);
+  mag = fabsf (x);
+
+  if (nan)
+    return x + x;
+
+  if (mag < (1 << __FLT_MANT_DIG__))
+    {
+      int32_t i;
+      float new_x;
+
+      asm ("fcvt.w.s %0, %1" : "=r" (i) : "f" (x));
+      asm ("fcvt.s.w %0, %1" : "=f" (new_x) : "r" (i));
+
+      /* rint(-0) == -0, and in general we'll always have the same
+	 sign as our input.  */
+      x = copysignf (new_x, x);
+    }
+
+  return x;
+}
+
+libm_alias_float (__rint, rint)
diff --git a/sysdeps/riscv/rvf/s_roundevenf.c b/sysdeps/riscv/rvf/s_roundevenf.c
new file mode 100644
index 0000000000..48086c28ee
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_roundevenf.c
@@ -0,0 +1,52 @@
+/* Round to nearest integer value, rounding halfway cases to even.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <math_private.h>
+#include <libm-alias-float.h>
+#include <stdint.h>
+
+float
+__roundevenf (float x)
+{
+  int flags = riscv_getflags ();
+  bool nan = isnan (x);
+  float mag = fabsf (x);
+
+  if (nan)
+    return x + x;
+
+  if (mag < (1 << __FLT_MANT_DIG__))
+    {
+      int32_t i;
+      float new_x;
+
+      asm volatile ("fcvt.w.s %0, %1, rne" : "=r" (i) : "f" (x));
+      asm volatile ("fcvt.s.w %0, %1, rne" : "=f" (new_x) : "r" (i));
+
+      /* roundeven(-0) == -0, and in general we'll always have the same
+	 sign as our input.  */
+      x = copysignf (new_x, x);
+
+      riscv_setflags (flags);
+    }
+
+  return x;
+}
+
+libm_alias_float (__roundeven, roundeven)
diff --git a/sysdeps/riscv/rvf/s_roundf.c b/sysdeps/riscv/rvf/s_roundf.c
new file mode 100644
index 0000000000..dedf57cbb3
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_roundf.c
@@ -0,0 +1,52 @@
+/* roundf().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <math_private.h>
+#include <libm-alias-float.h>
+#include <stdint.h>
+
+float
+__roundf (float x)
+{
+  int flags = riscv_getflags ();
+  bool nan = isnan (x);
+  float mag = fabsf (x);
+
+  if (nan)
+    return x + x;
+
+  if (mag < (1 << __FLT_MANT_DIG__))
+    {
+      int32_t i;
+      float new_x;
+
+      asm volatile ("fcvt.w.s %0, %1, rmm" : "=r" (i) : "f" (x));
+      asm volatile ("fcvt.s.w %0, %1, rmm" : "=f" (new_x) : "r" (i));
+
+      /* round(-0) == -0, and in general we'll always have the same
+	 sign as our input.  */
+      x = copysignf (new_x, x);
+
+      riscv_setflags (flags);
+    }
+
+  return x;
+}
+
+libm_alias_float (__round, round)
diff --git a/sysdeps/riscv/rvf/s_truncf.c b/sysdeps/riscv/rvf/s_truncf.c
new file mode 100644
index 0000000000..e23926a2ae
--- /dev/null
+++ b/sysdeps/riscv/rvf/s_truncf.c
@@ -0,0 +1,52 @@
+/* truncf().  RISC-V version.
+   Copyright (C) 2017-2018 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <math.h>
+#include <math_private.h>
+#include <libm-alias-float.h>
+#include <stdint.h>
+
+float
+__truncf (float x)
+{
+  int flags = riscv_getflags ();
+  bool nan = isnan (x);
+  float mag = fabsf (x);
+
+  if (nan)
+    return x + x;
+
+  if (mag < (1 << __FLT_MANT_DIG__))
+    {
+      int32_t i;
+      float new_x;
+
+      asm volatile ("fcvt.w.s %0, %1, rtz" : "=r" (i) : "f" (x));
+      asm volatile ("fcvt.s.w %0, %1, rtz" : "=f" (new_x) : "r" (i));
+
+      /* trunc(-0) == -0, and in general we'll always have the same
+	 sign as our input.  */
+      x = copysignf (new_x, x);
+
+      riscv_setflags (flags);
+    }
+
+  return x;
+}
+
+libm_alias_float (__trunc, trunc)