riscv: add fenv support from glibc

extra/Configs/Config.in.arch

@@ -170,6 +170,8 @@ config UCLIBC_HAS_FENV
 		   TARGET_mips || \
 		   TARGET_nds32 || \
 		   (TARGET_powerpc && CONFIG_E500) || \
+		   TARGET_riscv32 || \
+		   TARGET_riscv64 || \
 		   TARGET_x86_64
 	help
 	  If you want the uClibc math library to contain the C99 floating

libc/sysdeps/linux/riscv32/bits/fenv.h

@@ -64,10 +64,8 @@ typedef unsigned int fenv_t;
 /* If the default argument is used we use this value.  */
 #define FE_DFL_ENV	((__const fenv_t *) -1)
 
-#if __GLIBC_USE (IEC_60559_BFP_EXT)
 /* Type representing floating-point control modes.  */
 typedef unsigned int femode_t;
 
 /* Default floating-point control modes.  */
 # define FE_DFL_MODE	((const femode_t *) -1L)
-#endif

libc/sysdeps/linux/riscv64/bits/fenv.h

@@ -64,10 +64,8 @@ typedef unsigned int fenv_t;
 /* If the default argument is used we use this value.  */
 #define FE_DFL_ENV	((__const fenv_t *) -1)
 
-#if __GLIBC_USE (IEC_60559_BFP_EXT)
 /* Type representing floating-point control modes.  */
 typedef unsigned int femode_t;
 
 /* Default floating-point control modes.  */
 # define FE_DFL_MODE	((const femode_t *) -1L)
-#endif

libm/riscv32/Makefile.arch

@@ -0,0 +1,16 @@
+# Makefile for uClibc-ng
+# Licensed under the LGPL v2.1 or later, see the file COPYING.LIB in this tarball.
+
+ifeq ($(UCLIBC_HAS_FENV),y)
+libm_ARCH_SRC:=$(wildcard $(libm_ARCH_DIR)/*.c)
+libm_ARCH_OBJ:=$(patsubst $(libm_ARCH_DIR)/%.c,$(libm_ARCH_OUT)/%.o,$(libm_ARCH_SRC))
+endif
+
+libm_ARCH_OBJS:=$(libm_ARCH_OBJ)
+
+ifeq ($(DOPIC),y)
+libm-a-y+=$(libm_ARCH_OBJS:.o=.os)
+else
+libm-a-y+=$(libm_ARCH_OBJS)
+endif
+libm-so-y+=$(libm_ARCH_OBJS:.o=.os)

libm/riscv32/fclrexcpt.c

@@ -0,0 +1,26 @@
+/* Clear given exceptions in current floating-point environment.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+feclearexcept (int excepts)
+{
+  __asm__ volatile ("csrc fflags, %0" : : "r" (excepts));
+  return 0;
+}

libm/riscv32/fegetenv.c

@@ -0,0 +1,28 @@
+/* Store current floating-point environment.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+fegetenv (fenv_t *envp)
+{
+  _FPU_GETCW (*envp);
+
+  /* Success.  */
+  return 0;
+}

libm/riscv32/fegetmode.c

@@ -0,0 +1,26 @@
+/* Store current floating-point control modes.  RISC-V version.
+   Copyright (C) 2017-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+fegetmode (femode_t *modep)
+{
+  _FPU_GETCW (*modep);
+  return 0;
+}

libm/riscv32/fegetround.c

@@ -0,0 +1,25 @@
+/* Return current rounding direction.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_private.h"
+
+int
+fegetround (void)
+{
+  return riscv_getround ();
+}

libm/riscv32/feholdexcpt.c

@@ -0,0 +1,26 @@
+/* Store current floating-point environment and clear exceptions.
+   Copyright (C) 2000-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_private.h"
+
+int
+feholdexcept (fenv_t *envp)
+{
+  libc_feholdexcept_riscv (envp);
+  return 0;
+}

libm/riscv32/fenv_private.h

@@ -0,0 +1,156 @@
+/* Private floating point rounding and exceptions handling.  RISC-V version.
+   Copyright (C) 2014-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#ifndef RISCV_FENV_PRIVATE_H
+#define RISCV_FENV_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_feholdexcept_riscv (envp);
+  libc_fesetround_riscv (round);
+}
+
+#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 = (envp != FE_DFL_ENV ? *envp : 0);
+  _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)
+{
+  long int env = (envp != FE_DFL_ENV ? *envp : 0);
+  _FPU_SETCW (env | 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
+
+#endif

libm/riscv32/fesetenv.c

@@ -0,0 +1,26 @@
+/* Install given floating-point environment.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_private.h"
+
+int
+fesetenv (const fenv_t *envp)
+{
+  libc_fesetenv_riscv (envp);
+  return 0;
+}

libm/riscv32/fesetexcept.c

@@ -0,0 +1,25 @@
+/* Set given exception flags.  RISC-V version.
+   Copyright (C) 2017-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+
+int
+fesetexcept (int excepts)
+{
+  __asm__ volatile ("csrs fflags, %0" : : "r" (excepts));
+  return 0;
+}

libm/riscv32/fesetmode.c

@@ -0,0 +1,30 @@
+/* Install given floating-point control modes.  RISC-V version.
+   Copyright (C) 2017-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#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;
+}

libm/riscv32/fesetround.c

@@ -0,0 +1,35 @@
+/* Set current rounding direction.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_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/riscv32/feupdateenv.c

@@ -0,0 +1,26 @@
+/* Install given floating-point environment and raise exceptions.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_private.h"
+
+int
+feupdateenv (const fenv_t *envp)
+{
+  libc_feupdateenv_riscv (envp);
+  return 0;
+}

libm/riscv32/fgetexcptflg.c

@@ -0,0 +1,29 @@
+/* Store current representation for exceptions.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_private.h"
+
+int
+fegetexceptflag (fexcept_t *flagp, int excepts)
+{
+  /* Get the current exceptions.  */
+  *flagp = riscv_getflags () & excepts;
+
+  /* Success.  */
+  return 0;
+}

libm/riscv32/fraiseexcpt.c

@@ -0,0 +1,26 @@
+/* Raise given exceptions.
+   Copyright (C) 2000-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+feraiseexcept (int excepts)
+{
+  __asm__ volatile ("csrs fflags, %0" : : "r" (excepts));
+  return 0;
+}

libm/riscv32/fsetexcptflg.c

@@ -0,0 +1,29 @@
+/* Set floating-point environment exception handling.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#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;
+}

libm/riscv32/ftestexcept.c

@@ -0,0 +1,25 @@
+/* Test exception in current environment.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_private.h"
+
+int
+fetestexcept (int excepts)
+{
+  return libc_fetestexcept_riscv (excepts);
+}

libm/riscv32/get-rounding-mode.h

@@ -0,0 +1,32 @@
+/* Determine floating-point rounding mode within libc.  RISC-V version.
+   Copyright (C) 2015-2025 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/>.  */
+
+#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 */

libm/riscv64/Makefile.arch

@@ -0,0 +1,16 @@
+# Makefile for uClibc-ng
+# Licensed under the LGPL v2.1 or later, see the file COPYING.LIB in this tarball.
+
+ifeq ($(UCLIBC_HAS_FENV),y)
+libm_ARCH_SRC:=$(wildcard $(libm_ARCH_DIR)/*.c)
+libm_ARCH_OBJ:=$(patsubst $(libm_ARCH_DIR)/%.c,$(libm_ARCH_OUT)/%.o,$(libm_ARCH_SRC))
+endif
+
+libm_ARCH_OBJS:=$(libm_ARCH_OBJ)
+
+ifeq ($(DOPIC),y)
+libm-a-y+=$(libm_ARCH_OBJS:.o=.os)
+else
+libm-a-y+=$(libm_ARCH_OBJS)
+endif
+libm-so-y+=$(libm_ARCH_OBJS:.o=.os)

libm/riscv64/fclrexcpt.c

@@ -0,0 +1,26 @@
+/* Clear given exceptions in current floating-point environment.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+feclearexcept (int excepts)
+{
+  __asm__ volatile ("csrc fflags, %0" : : "r" (excepts));
+  return 0;
+}

libm/riscv64/fegetenv.c

@@ -0,0 +1,28 @@
+/* Store current floating-point environment.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+fegetenv (fenv_t *envp)
+{
+  _FPU_GETCW (*envp);
+
+  /* Success.  */
+  return 0;
+}

libm/riscv64/fegetmode.c

@@ -0,0 +1,26 @@
+/* Store current floating-point control modes.  RISC-V version.
+   Copyright (C) 2017-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+fegetmode (femode_t *modep)
+{
+  _FPU_GETCW (*modep);
+  return 0;
+}

libm/riscv64/fegetround.c

@@ -0,0 +1,25 @@
+/* Return current rounding direction.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_private.h"
+
+int
+fegetround (void)
+{
+  return riscv_getround ();
+}

libm/riscv64/feholdexcpt.c

@@ -0,0 +1,26 @@
+/* Store current floating-point environment and clear exceptions.
+   Copyright (C) 2000-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_private.h"
+
+int
+feholdexcept (fenv_t *envp)
+{
+  libc_feholdexcept_riscv (envp);
+  return 0;
+}

libm/riscv64/fenv_private.h

@@ -0,0 +1,156 @@
+/* Private floating point rounding and exceptions handling.  RISC-V version.
+   Copyright (C) 2014-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#ifndef RISCV_FENV_PRIVATE_H
+#define RISCV_FENV_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_feholdexcept_riscv (envp);
+  libc_fesetround_riscv (round);
+}
+
+#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 = (envp != FE_DFL_ENV ? *envp : 0);
+  _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)
+{
+  long int env = (envp != FE_DFL_ENV ? *envp : 0);
+  _FPU_SETCW (env | 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
+
+#endif

libm/riscv64/fesetenv.c

@@ -0,0 +1,26 @@
+/* Install given floating-point environment.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_private.h"
+
+int
+fesetenv (const fenv_t *envp)
+{
+  libc_fesetenv_riscv (envp);
+  return 0;
+}

libm/riscv64/fesetexcept.c

@@ -0,0 +1,25 @@
+/* Set given exception flags.  RISC-V version.
+   Copyright (C) 2017-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+
+int
+fesetexcept (int excepts)
+{
+  __asm__ volatile ("csrs fflags, %0" : : "r" (excepts));
+  return 0;
+}

libm/riscv64/fesetmode.c

@@ -0,0 +1,30 @@
+/* Install given floating-point control modes.  RISC-V version.
+   Copyright (C) 2017-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#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;
+}

libm/riscv64/fesetround.c

@@ -0,0 +1,35 @@
+/* Set current rounding direction.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_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/riscv64/feupdateenv.c

@@ -0,0 +1,26 @@
+/* Install given floating-point environment and raise exceptions.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_private.h"
+
+int
+feupdateenv (const fenv_t *envp)
+{
+  libc_feupdateenv_riscv (envp);
+  return 0;
+}

libm/riscv64/fgetexcptflg.c

@@ -0,0 +1,29 @@
+/* Store current representation for exceptions.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_private.h"
+
+int
+fegetexceptflag (fexcept_t *flagp, int excepts)
+{
+  /* Get the current exceptions.  */
+  *flagp = riscv_getflags () & excepts;
+
+  /* Success.  */
+  return 0;
+}

libm/riscv64/fraiseexcpt.c

@@ -0,0 +1,26 @@
+/* Raise given exceptions.
+   Copyright (C) 2000-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+feraiseexcept (int excepts)
+{
+  __asm__ volatile ("csrs fflags, %0" : : "r" (excepts));
+  return 0;
+}

libm/riscv64/fsetexcptflg.c

@@ -0,0 +1,29 @@
+/* Set floating-point environment exception handling.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#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;
+}

libm/riscv64/ftestexcept.c

@@ -0,0 +1,25 @@
+/* Test exception in current environment.
+   Copyright (C) 1998-2025 Free Software Foundation, Inc.
+
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_private.h"
+
+int
+fetestexcept (int excepts)
+{
+  return libc_fetestexcept_riscv (excepts);
+}

libm/riscv64/get-rounding-mode.h

@@ -0,0 +1,32 @@
+/* Determine floating-point rounding mode within libc.  RISC-V version.
+   Copyright (C) 2015-2025 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/>.  */
+
+#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 */