LoongArch: Hard Float Support

sysdeps/loongarch/fpu/fclrexcpt.c

@@ -0,0 +1,46 @@
+/* Clear given exceptions in current floating-point environment.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fenv_libc.h>
+#include <fpu_control.h>
+
+int
+feclearexcept (int excepts)
+{
+  int cw;
+
+  /* Mask out unsupported bits/exceptions.  */
+  excepts &= FE_ALL_EXCEPT;
+
+  /* Read the complete control word.  */
+  _FPU_GETCW (cw);
+
+  /* Clear exception flag bits and cause bits.  If the cause bit is not
+     cleared, the next CTC instruction (just below) will re-generate the
+     exception.  */
+
+  cw &= ~(excepts | (excepts << CAUSE_SHIFT));
+
+  /* Put the new data in effect.  */
+  _FPU_SETCW (cw);
+
+  /* Success.  */
+  return 0;
+}
+libm_hidden_def (feclearexcept)

sysdeps/loongarch/fpu/fedisblxcpt.c

@@ -0,0 +1,39 @@
+/* Disable floating-point exceptions.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fenv_libc.h>
+#include <fpu_control.h>
+
+int
+fedisableexcept (int excepts)
+{
+  unsigned int new_exc, old_exc;
+
+  /* Get the current control word.  */
+  _FPU_GETCW (new_exc);
+
+  old_exc = (new_exc & ENABLE_MASK) << ENABLE_SHIFT;
+
+  excepts &= FE_ALL_EXCEPT;
+
+  new_exc &= ~(excepts >> ENABLE_SHIFT);
+  _FPU_SETCW (new_exc);
+
+  return old_exc;
+}

sysdeps/loongarch/fpu/feenablxcpt.c

@@ -0,0 +1,39 @@
+/* Enable floating-point exceptions.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fenv_libc.h>
+#include <fpu_control.h>
+
+int
+feenableexcept (int excepts)
+{
+  unsigned int new_exc, old_exc;
+
+  /* Get the current control word.  */
+  _FPU_GETCW (new_exc);
+
+  old_exc = (new_exc & ENABLE_MASK) << ENABLE_SHIFT;
+
+  excepts &= FE_ALL_EXCEPT;
+
+  new_exc |= excepts >> ENABLE_SHIFT;
+  _FPU_SETCW (new_exc);
+
+  return old_exc;
+}

sysdeps/loongarch/fpu/fegetenv.c

@@ -0,0 +1,31 @@
+/* Store current floating-point environment.
+   Copyright (C) 2022 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/>.  */
+
+#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)

sysdeps/loongarch/fpu/fegetexcept.c

@@ -0,0 +1,32 @@
+/* Get enabled floating-point exceptions.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fenv_libc.h>
+#include <fpu_control.h>
+
+int
+fegetexcept (void)
+{
+  unsigned int exc;
+
+  /* Get the current control word.  */
+  _FPU_GETCW (exc);
+
+  return (exc & ENABLE_MASK) << ENABLE_SHIFT;
+}

sysdeps/loongarch/fpu/fegetmode.c

@@ -0,0 +1,27 @@
+/* Store current floating-point control modes.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+fegetmode (femode_t *modep)
+{
+  _FPU_GETCW (*modep);
+  return 0;
+}

sysdeps/loongarch/fpu/fegetround.c

@@ -0,0 +1,33 @@
+/* Return current rounding direction.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+__fegetround (void)
+{
+  int cw;
+
+  /* Get control word.  */
+  _FPU_GETCW (cw);
+
+  return cw & _FPU_RC_MASK;
+}
+libm_hidden_def (__fegetround) weak_alias (__fegetround, fegetround)
+libm_hidden_weak (fegetround)

sysdeps/loongarch/fpu/feholdexcpt.c

@@ -0,0 +1,40 @@
+/* Store current floating-point environment and clear exceptions.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+__feholdexcept (fenv_t *envp)
+{
+  fpu_control_t cw;
+
+  /* Save the current state.  */
+  _FPU_GETCW (cw);
+  envp->__fp_control_register = cw;
+
+  /* Clear all exception enable bits and flags.  */
+  cw &= ~(_FPU_MASK_V | _FPU_MASK_Z | _FPU_MASK_O | _FPU_MASK_U | _FPU_MASK_I
+	  | FE_ALL_EXCEPT);
+  _FPU_SETCW (cw);
+
+  return 0;
+}
+
+libm_hidden_def (__feholdexcept) weak_alias (__feholdexcept, feholdexcept)
+libm_hidden_weak (feholdexcept)

sysdeps/loongarch/fpu/fenv_libc.h

@@ -0,0 +1,30 @@
+/* Internal libc stuff for floating point environment routines.
+   Copyright (C) 2022 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 _FENV_LIBC_H
+#define _FENV_LIBC_H 1
+
+/* Mask for enabling exceptions and for the CAUSE bits.  */
+#define ENABLE_MASK 0x0000001FU
+#define CAUSE_MASK 0x1F000000U
+
+/* Shift for FE_* flags to get up to the ENABLE bits and the CAUSE bits.  */
+#define ENABLE_SHIFT 16
+#define CAUSE_SHIFT 8
+
+#endif /* _FENV_LIBC_H */

sysdeps/loongarch/fpu/fesetenv.c

@@ -0,0 +1,42 @@
+/* Install given floating-point environment.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+__fesetenv (const fenv_t *envp)
+{
+  fpu_control_t cw;
+
+  /* Read first current state to flush fpu pipeline.  */
+  _FPU_GETCW (cw);
+
+  if (envp == FE_DFL_ENV)
+    _FPU_SETCW (_FPU_DEFAULT);
+  else if (envp == FE_NOMASK_ENV)
+    _FPU_SETCW (_FPU_IEEE);
+  else
+    _FPU_SETCW (envp->__fp_control_register);
+
+  /* Success.  */
+  return 0;
+}
+
+libm_hidden_def (__fesetenv) weak_alias (__fesetenv, fesetenv)
+libm_hidden_weak (fesetenv)

sysdeps/loongarch/fpu/fesetexcept.c

@@ -0,0 +1,32 @@
+/* Set given exception flags.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+fesetexcept (int excepts)
+{
+  fpu_control_t temp;
+
+  _FPU_GETCW (temp);
+  temp |= excepts & FE_ALL_EXCEPT;
+  _FPU_SETCW (temp);
+
+  return 0;
+}

sysdeps/loongarch/fpu/fesetmode.c

@@ -0,0 +1,38 @@
+/* Install given floating-point control modes.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+#define FCSR_STATUS 0x1f1f0000
+
+int
+fesetmode (const femode_t *modep)
+{
+  fpu_control_t cw;
+
+  _FPU_GETCW (cw);
+  cw &= FCSR_STATUS;
+  if (modep == FE_DFL_MODE)
+    cw |= _FPU_DEFAULT;
+  else
+    cw |= *modep & ~FCSR_STATUS;
+  _FPU_SETCW (cw);
+
+  return 0;
+}

sysdeps/loongarch/fpu/fesetround.c

@@ -0,0 +1,44 @@
+/* Set current rounding direction.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+__fesetround (int round)
+{
+  fpu_control_t cw;
+
+  if ((round & ~_FPU_RC_MASK) != 0)
+    /* ROUND is no valid rounding mode.  */
+    return 1;
+
+  /* Get current state.  */
+  _FPU_GETCW (cw);
+
+  /* Set rounding bits.  */
+  cw &= ~_FPU_RC_MASK;
+  cw |= round;
+  /* Set new state.  */
+  _FPU_SETCW (cw);
+
+  return 0;
+}
+
+libm_hidden_def (__fesetround) weak_alias (__fesetround, fesetround)
+libm_hidden_weak (fesetround)

sysdeps/loongarch/fpu/feupdateenv.c

@@ -0,0 +1,43 @@
+/* Install given floating-point environment and raise exceptions.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+__feupdateenv (const fenv_t *envp)
+{
+  int temp;
+
+  /* Save current exceptions.  */
+  _FPU_GETCW (temp);
+  temp &= FE_ALL_EXCEPT;
+
+  /* Install new environment.  */
+  __fesetenv (envp);
+
+  /* Raise the safed exception.  Incidently for us the implementation
+     defined format of the values in objects of type fexcept_t is the
+     same as the ones specified using the FE_* constants.  */
+  __feraiseexcept (temp);
+
+  /* Success.  */
+  return 0;
+}
+libm_hidden_def (__feupdateenv) weak_alias (__feupdateenv, feupdateenv)
+libm_hidden_weak (feupdateenv)

sysdeps/loongarch/fpu/fgetexcptflg.c

@@ -0,0 +1,38 @@
+/* Store current representation for exceptions.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+fegetexceptflag (fexcept_t *flagp, int excepts)
+{
+  fpu_control_t temp;
+
+  /* Get the current exceptions.  */
+  _FPU_GETCW (temp);
+
+  /* We only save the relevant bits here.  In particular, care has to be
+     taken with the CAUSE bits, as an inadvertent restore later on could
+     generate unexpected exceptions.  */
+
+  *flagp = temp & excepts & FE_ALL_EXCEPT;
+
+  /* Success.  */
+  return 0;
+}

sysdeps/loongarch/fpu/fraiseexcpt.c

@@ -0,0 +1,80 @@
+/* Raise given exceptions.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+#include <float.h>
+
+int
+__feraiseexcept (int excepts)
+{
+  const float fp_zero = 0.0f;
+  const float fp_one = 1.0f;
+  const float fp_max = FLT_MAX;
+  const float fp_min = FLT_MIN;
+  const float fp_1e32 = 1.0e32f;
+  const float fp_two = 2.0f;
+  const float fp_three = 3.0f;
+
+  /* Raise exceptions represented by EXPECTS.  But we must raise only
+     one signal at a time.  It is important that if the overflow/underflow
+     exception and the inexact exception are given at the same time,
+     the overflow/underflow exception follows the inexact exception.  */
+
+  /* First: invalid exception.  */
+  if (FE_INVALID & excepts)
+    __asm__ __volatile__("fdiv.s $f0,%0,%0\n\t"
+			 :
+			 : "f"(fp_zero)
+			 : "$f0");
+
+  /* Next: division by zero.  */
+  if (FE_DIVBYZERO & excepts)
+    __asm__ __volatile__("fdiv.s $f0,%0,%1\n\t"
+			 :
+			 : "f"(fp_one), "f"(fp_zero)
+			 : "$f0");
+
+  /* Next: overflow.  */
+  if (FE_OVERFLOW & excepts)
+    /* There's no way to raise overflow without also raising inexact.  */
+    __asm__ __volatile__("fadd.s $f0,%0,%1\n\t"
+			 :
+			 : "f"(fp_max), "f"(fp_1e32)
+			 : "$f0");
+
+  /* Next: underflow.  */
+  if (FE_UNDERFLOW & excepts)
+    __asm__ __volatile__("fdiv.s $f0,%0,%1\n\t"
+			 :
+			 : "f"(fp_min), "f"(fp_three)
+			 : "$f0");
+
+  /* Last: inexact.  */
+  if (FE_INEXACT & excepts)
+    __asm__ __volatile__("fdiv.s $f0, %0, %1\n\t"
+			 :
+			 : "f"(fp_two), "f"(fp_three)
+			 : "$f0");
+
+  /* Success.  */
+  return 0;
+}
+
+libm_hidden_def (__feraiseexcept) weak_alias (__feraiseexcept, feraiseexcept)
+libm_hidden_weak (feraiseexcept)

sysdeps/loongarch/fpu/fsetexcptflg.c

@@ -0,0 +1,41 @@
+/* Set floating-point environment exception handling.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+fesetexceptflag (const fexcept_t *flagp, int excepts)
+{
+  fpu_control_t temp;
+
+  /* Get the current exceptions.  */
+  _FPU_GETCW (temp);
+
+  /* Make sure the flags we want restored are legal.  */
+  excepts &= FE_ALL_EXCEPT;
+
+  /* Now clear the bits called for, and copy them in from flagp.  Note that
+     we ignore all non-flag bits from *flagp, so they don't matter.  */
+  temp = (temp & ~excepts) | (*flagp & excepts);
+
+  _FPU_SETCW (temp);
+
+  /* Success.  */
+  return 0;
+}

sysdeps/loongarch/fpu/ftestexcept.c

@@ -0,0 +1,32 @@
+/* Test exception in current environment.
+   Copyright (C) 2022 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/>.  */
+
+#include <fenv.h>
+#include <fpu_control.h>
+
+int
+fetestexcept (int excepts)
+{
+  int cw;
+
+  /* Get current control word.  */
+  _FPU_GETCW (cw);
+
+  return cw & excepts & FE_ALL_EXCEPT;
+}
+libm_hidden_def (fetestexcept)

sysdeps/loongarch/fpu/math-use-builtins-sqrt.h

@@ -0,0 +1,4 @@
+#define USE_SQRT_BUILTIN 1
+#define USE_SQRTF_BUILTIN 1
+#define USE_SQRTL_BUILTIN 0
+#define USE_SQRTF128_BUILTIN 0

sysdeps/loongarch/lp64/libm-test-ulps-name

@@ -0,0 +1 @@
+LoongArch 64-bit

sysdeps/loongarch/math_private.h

@@ -0,0 +1,248 @@
+/* Internal math stuff.
+   Copyright (C) 2022 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 LOONGARCH_MATH_PRIVATE_H
+#define LOONGARCH_MATH_PRIVATE_H 1
+
+/* Inline functions to speed up the math library implementation.  The
+   default versions of these routines are in generic/math_private.h
+   and call fesetround, feholdexcept, etc.  These routines use inlined
+   code instead.  */
+
+#ifdef __loongarch_hard_float
+
+#include <fenv.h>
+#include <fenv_libc.h>
+#include <fpu_control.h>
+
+#define _FPU_MASK_ALL \
+  (_FPU_MASK_V | _FPU_MASK_Z | _FPU_MASK_O | _FPU_MASK_U | _FPU_MASK_I \
+   | FE_ALL_EXCEPT)
+
+static __always_inline void
+libc_feholdexcept_loongarch (fenv_t *envp)
+{
+  fpu_control_t cw;
+
+  /* Save the current state.  */
+  _FPU_GETCW (cw);
+  envp->__fp_control_register = cw;
+
+  /* Clear all exception enable bits and flags.  */
+  cw &= ~(_FPU_MASK_ALL);
+  _FPU_SETCW (cw);
+}
+#define libc_feholdexcept libc_feholdexcept_loongarch
+#define libc_feholdexceptf libc_feholdexcept_loongarch
+#define libc_feholdexceptl libc_feholdexcept_loongarch
+
+static __always_inline void
+libc_fesetround_loongarch (int round)
+{
+  fpu_control_t cw;
+
+  /* Get current state.  */
+  _FPU_GETCW (cw);
+
+  /* Set rounding bits.  */
+  cw &= ~_FPU_RC_MASK;
+  cw |= round;
+
+  /* Set new state.  */
+  _FPU_SETCW (cw);
+}
+#define libc_fesetround libc_fesetround_loongarch
+#define libc_fesetroundf libc_fesetround_loongarch
+#define libc_fesetroundl libc_fesetround_loongarch
+
+static __always_inline void
+libc_feholdexcept_setround_loongarch (fenv_t *envp, int round)
+{
+  fpu_control_t cw;
+
+  /* Save the current state.  */
+  _FPU_GETCW (cw);
+  envp->__fp_control_register = cw;
+
+  /* Clear all exception enable bits and flags.  */
+  cw &= ~(_FPU_MASK_ALL);
+
+  /* Set rounding bits.  */
+  cw &= ~_FPU_RC_MASK;
+  cw |= round;
+
+  /* Set new state.  */
+  _FPU_SETCW (cw);
+}
+#define libc_feholdexcept_setround libc_feholdexcept_setround_loongarch
+#define libc_feholdexcept_setroundf libc_feholdexcept_setround_loongarch
+#define libc_feholdexcept_setroundl libc_feholdexcept_setround_loongarch
+
+#define libc_feholdsetround libc_feholdexcept_setround_loongarch
+#define libc_feholdsetroundf libc_feholdexcept_setround_loongarch
+#define libc_feholdsetroundl libc_feholdexcept_setround_loongarch
+
+static __always_inline void
+libc_fesetenv_loongarch (fenv_t *envp)
+{
+  fpu_control_t cw __attribute__ ((unused));
+
+  /* Read current state to flush fpu pipeline.  */
+  _FPU_GETCW (cw);
+
+  _FPU_SETCW (envp->__fp_control_register);
+}
+#define libc_fesetenv libc_fesetenv_loongarch
+#define libc_fesetenvf libc_fesetenv_loongarch
+#define libc_fesetenvl libc_fesetenv_loongarch
+
+static __always_inline int
+libc_feupdateenv_test_loongarch (fenv_t *envp, int excepts)
+{
+  /* int ret = fetestexcept (excepts); feupdateenv (envp); return ret; */
+  int cw, temp;
+
+  /* Get current control word.  */
+  _FPU_GETCW (cw);
+
+  /* Set flag bits (which are accumulative), and *also* set the
+     cause bits.  The setting of the cause bits is what actually causes
+     the hardware to generate the exception, if the corresponding enable
+     bit is set as well.  */
+  temp = cw & FE_ALL_EXCEPT;
+  temp |= envp->__fp_control_register | (temp << CAUSE_SHIFT);
+
+  /* Set new state.  */
+  _FPU_SETCW (temp);
+
+  return cw & excepts & FE_ALL_EXCEPT;
+}
+#define libc_feupdateenv_test libc_feupdateenv_test_loongarch
+#define libc_feupdateenv_testf libc_feupdateenv_test_loongarch
+#define libc_feupdateenv_testl libc_feupdateenv_test_loongarch
+
+static __always_inline void
+libc_feupdateenv_loongarch (fenv_t *envp)
+{
+  libc_feupdateenv_test_loongarch (envp, 0);
+}
+#define libc_feupdateenv libc_feupdateenv_loongarch
+#define libc_feupdateenvf libc_feupdateenv_loongarch
+#define libc_feupdateenvl libc_feupdateenv_loongarch
+
+#define libc_feresetround libc_feupdateenv_loongarch
+#define libc_feresetroundf libc_feupdateenv_loongarch
+#define libc_feresetroundl libc_feupdateenv_loongarch
+
+static __always_inline int
+libc_fetestexcept_loongarch (int excepts)
+{
+  int cw;
+
+  /* Get current control word.  */
+  _FPU_GETCW (cw);
+
+  return cw & excepts & FE_ALL_EXCEPT;
+}
+#define libc_fetestexcept libc_fetestexcept_loongarch
+#define libc_fetestexceptf libc_fetestexcept_loongarch
+#define libc_fetestexceptl libc_fetestexcept_loongarch
+
+/*  Enable support for rounding mode context.  */
+#define HAVE_RM_CTX 1
+
+static __always_inline void
+libc_feholdexcept_setround_loongarch_ctx (struct rm_ctx *ctx, int round)
+{
+  fpu_control_t old, new;
+
+  /* Save the current state.  */
+  _FPU_GETCW (old);
+  ctx->env.__fp_control_register = old;
+
+  /* Clear all exception enable bits and flags.  */
+  new = old & ~(_FPU_MASK_ALL);
+
+  /* Set rounding bits.  */
+  new = (new & ~_FPU_RC_MASK) | round;
+
+  if (__glibc_unlikely (new != old))
+    {
+      _FPU_SETCW (new);
+      ctx->updated_status = true;
+    }
+  else
+    ctx->updated_status = false;
+}
+#define libc_feholdexcept_setround_ctx libc_feholdexcept_setround_loongarch_ctx
+#define libc_feholdexcept_setroundf_ctx \
+  libc_feholdexcept_setround_loongarch_ctx
+#define libc_feholdexcept_setroundl_ctx \
+  libc_feholdexcept_setround_loongarch_ctx
+
+static __always_inline void
+libc_fesetenv_loongarch_ctx (struct rm_ctx *ctx)
+{
+  libc_fesetenv_loongarch (&ctx->env);
+}
+#define libc_fesetenv_ctx libc_fesetenv_loongarch_ctx
+#define libc_fesetenvf_ctx libc_fesetenv_loongarch_ctx
+#define libc_fesetenvl_ctx libc_fesetenv_loongarch_ctx
+
+static __always_inline void
+libc_feupdateenv_loongarch_ctx (struct rm_ctx *ctx)
+{
+  if (__glibc_unlikely (ctx->updated_status))
+    libc_feupdateenv_test_loongarch (&ctx->env, 0);
+}
+#define libc_feupdateenv_ctx libc_feupdateenv_loongarch_ctx
+#define libc_feupdateenvf_ctx libc_feupdateenv_loongarch_ctx
+#define libc_feupdateenvl_ctx libc_feupdateenv_loongarch_ctx
+#define libc_feresetround_ctx libc_feupdateenv_loongarch_ctx
+#define libc_feresetroundf_ctx libc_feupdateenv_loongarch_ctx
+#define libc_feresetroundl_ctx libc_feupdateenv_loongarch_ctx
+
+static __always_inline void
+libc_feholdsetround_loongarch_ctx (struct rm_ctx *ctx, int round)
+{
+  fpu_control_t old, new;
+
+  /* Save the current state.  */
+  _FPU_GETCW (old);
+  ctx->env.__fp_control_register = old;
+
+  /* Set rounding bits.  */
+  new = (old & ~_FPU_RC_MASK) | round;
+
+  if (__glibc_unlikely (new != old))
+    {
+      _FPU_SETCW (new);
+      ctx->updated_status = true;
+    }
+  else
+    ctx->updated_status = false;
+}
+#define libc_feholdsetround_ctx libc_feholdsetround_loongarch_ctx
+#define libc_feholdsetroundf_ctx libc_feholdsetround_loongarch_ctx
+#define libc_feholdsetroundl_ctx libc_feholdsetround_loongarch_ctx
+
+#endif
+
+#include_next <math_private.h>
+
+#endif