1 files changed, 277 insertions, 0 deletions
diff --git a/libm/csky/fenv_private.h b/libm/csky/fenv_private.h
new file mode 100644
index 000000000..f0f48a88a
--- /dev/null
+++ b/libm/csky/fenv_private.h
@@ -0,0 +1,277 @@
+/* Private floating point rounding and exceptions handling.  C-SKY version.
+   Copyright (C) 2018-2025 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 CSKY_FENV_PRIVATE_H
+#define CSKY_FENV_PRIVATE_H 1
+
+#include <fenv.h>
+#include <fpu_control.h>
+#include "fenv_libc.h"
+
+static __always_inline void
+libc_feholdexcept_vfp (fenv_t *envp)
+{
+  fpu_control_t fpsr, fpcr;
+
+  _FPU_GETCW (fpcr);
+  envp->__fpcr = fpcr;
+
+  _FPU_GETFPSR (fpsr);
+  envp->__fpsr = fpsr;
+
+  /* Now set all exceptions to non-stop.  */
+  fpcr &= ~FE_ALL_EXCEPT;
+
+  /* And clear all exception flags.  */
+  fpsr &= ~(FE_ALL_EXCEPT << CAUSE_SHIFT);
+
+  _FPU_SETFPSR (fpsr);
+
+  _FPU_SETCW (fpcr);
+}
+
+static __always_inline void
+libc_fesetround_vfp (int round)
+{
+  fpu_control_t fpcr;
+
+  _FPU_GETCW (fpcr);
+
+  /* Set new rounding mode if different.  */
+  if (unlikely ((fpcr & FE_DOWNWARD) != round))
+    _FPU_SETCW ((fpcr & ~FE_DOWNWARD) | round);
+}
+
+static __always_inline void
+libc_feholdexcept_setround_vfp (fenv_t *envp, int round)
+{
+  fpu_control_t fpsr, fpcr;
+
+  _FPU_GETCW (fpcr);
+  envp->__fpcr = fpcr;
+
+  _FPU_GETFPSR (fpsr);
+  envp->__fpsr = fpsr;
+
+  /* Clear exception flags, set all exceptions to non-stop,
+     and set new rounding mode.  */
+  fpsr &= ~(FE_ALL_EXCEPT << CAUSE_SHIFT);
+  _FPU_SETFPSR (fpsr);
+
+  fpcr &= ~(FE_ALL_EXCEPT | FE_DOWNWARD);
+  _FPU_SETCW (fpcr | round);
+}
+
+static __always_inline void
+libc_feholdsetround_vfp (fenv_t *envp, int round)
+{
+  fpu_control_t fpcr;
+
+  _FPU_GETCW (fpcr);
+  envp->__fpcr = fpcr;
+
+  /* Set new rounding mode if different.  */
+  if (unlikely ((fpcr & FE_DOWNWARD) != round))
+    _FPU_SETCW ((fpcr & ~FE_DOWNWARD) | round);
+}
+
+static __always_inline void
+libc_feresetround_vfp (fenv_t *envp)
+{
+  fpu_control_t fpcr, round;
+
+  _FPU_GETCW (fpcr);
+
+  /* Check whether rounding modes are different.  */
+  round = (envp->__fpcr ^ fpcr) & FE_DOWNWARD;
+
+  /* Restore the rounding mode if it was changed.  */
+  if (unlikely (round != 0))
+    _FPU_SETCW (fpcr ^ round);
+}
+
+static __always_inline int
+libc_fetestexcept_vfp (int ex)
+{
+  fpu_control_t fpsr;
+
+  _FPU_GETFPSR (fpsr);
+  fpsr = fpsr >> CAUSE_SHIFT;
+  return fpsr & ex & FE_ALL_EXCEPT;
+}
+
+static __always_inline void
+libc_fesetenv_vfp (const fenv_t *envp)
+{
+  fpu_control_t fpcr, fpsr, new_fpcr, new_fpsr;
+
+  _FPU_GETCW (fpcr);
+  _FPU_GETFPSR (fpsr);
+
+  new_fpcr = envp->__fpcr;
+  new_fpsr = envp->__fpsr;
+
+  if (unlikely (fpsr ^ new_fpsr) != 0)
+    _FPU_SETFPSR (new_fpsr);
+
+  if (unlikely (fpcr ^ new_fpcr) != 0)
+    _FPU_SETCW (new_fpcr);
+}
+
+static __always_inline int
+libc_feupdateenv_test_vfp (const fenv_t *envp, int ex)
+{
+  fpu_control_t fpcr, fpsr, new_fpcr, new_fpsr, excepts;
+
+  _FPU_GETCW (fpcr);
+  _FPU_GETFPSR (fpsr);
+
+  /* Merge current exception flags with the saved fenv.  */
+  excepts = (fpsr >> CAUSE_SHIFT) & FE_ALL_EXCEPT;
+  new_fpcr = envp->__fpcr;
+  new_fpsr = envp->__fpsr | (excepts << CAUSE_SHIFT);
+
+  /* Write FCR and FESR if different.  */
+  if (unlikely (fpsr ^ new_fpsr) != 0)
+    _FPU_SETFPSR (new_fpsr);
+
+  if (unlikely (fpcr ^ new_fpcr) != 0)
+    _FPU_SETCW (new_fpcr);
+
+  /* Raise the exceptions if enabled in the new FP state.  */
+  if (unlikely (excepts & new_fpcr))
+    feraiseexcept (excepts);
+
+  return excepts & ex;
+}
+
+static __always_inline void
+libc_feupdateenv_vfp (const fenv_t *envp)
+{
+  libc_feupdateenv_test_vfp (envp, 0);
+}
+
+static __always_inline void
+libc_feholdsetround_vfp_ctx (struct rm_ctx *ctx, int r)
+{
+  fpu_control_t fpcr, fpsr, round;
+
+  _FPU_GETCW (fpcr);
+  _FPU_GETFPSR (fpsr);
+  ctx->updated_status = false;
+  ctx->env.__fpcr = fpcr;
+  ctx->env.__fpsr = fpsr;
+
+  /* Check whether rounding modes are different.  */
+  round = (fpcr ^ r) & FE_DOWNWARD;
+
+  /* Set the rounding mode if changed.  */
+  if (unlikely (round != 0))
+    {
+      ctx->updated_status = true;
+      _FPU_SETCW (fpcr ^ round);
+    }
+}
+
+static __always_inline void
+libc_feresetround_vfp_ctx (struct rm_ctx *ctx)
+{
+  /* Restore the rounding mode if updated.  */
+  if (unlikely (ctx->updated_status))
+    {
+      fpu_control_t fpcr;
+
+      _FPU_GETCW (fpcr);
+      fpcr = (fpcr & ~FE_DOWNWARD) | (ctx->env.__fpcr & FE_DOWNWARD);
+      _FPU_SETCW (fpcr);
+    }
+}
+
+static __always_inline void
+libc_fesetenv_vfp_ctx (struct rm_ctx *ctx)
+{
+  fpu_control_t fpcr, fpsr, new_fpcr, new_fpsr;
+
+  _FPU_GETCW (fpcr);
+  _FPU_GETFPSR (fpsr);
+
+  new_fpcr = ctx->env.__fpcr;
+  new_fpsr = ctx->env.__fpsr;
+
+  if (unlikely (fpsr ^ new_fpsr) != 0)
+    _FPU_SETFPSR (new_fpsr);
+
+  if (unlikely (fpcr ^ new_fpcr) != 0)
+    _FPU_SETCW (new_fpcr);
+}
+
+#define libc_feholdexcept  libc_feholdexcept_vfp
+#define libc_feholdexceptf libc_feholdexcept_vfp
+#define libc_feholdexceptl libc_feholdexcept_vfp
+
+#define libc_fesetround  libc_fesetround_vfp
+#define libc_fesetroundf libc_fesetround_vfp
+#define libc_fesetroundl libc_fesetround_vfp
+
+#define libc_feresetround  libc_feresetround_vfp
+#define libc_feresetroundf libc_feresetround_vfp
+#define libc_feresetroundl libc_feresetround_vfp
+
+#define libc_feresetround_noex  libc_fesetenv_vfp
+#define libc_feresetround_noexf libc_fesetenv_vfp
+#define libc_feresetround_noexl libc_fesetenv_vfp
+
+#define libc_feholdexcept_setround  libc_feholdexcept_setround_vfp
+#define libc_feholdexcept_setroundf libc_feholdexcept_setround_vfp
+#define libc_feholdexcept_setroundl libc_feholdexcept_setround_vfp
+
+#define libc_feholdsetround  libc_feholdsetround_vfp
+#define libc_feholdsetroundf libc_feholdsetround_vfp
+#define libc_feholdsetroundl libc_feholdsetround_vfp
+
+#define libc_fetestexcept  libc_fetestexcept_vfp
+#define libc_fetestexceptf libc_fetestexcept_vfp
+#define libc_fetestexceptl libc_fetestexcept_vfp
+
+#define libc_fesetenv  libc_fesetenv_vfp
+#define libc_fesetenvf libc_fesetenv_vfp
+#define libc_fesetenvl libc_fesetenv_vfp
+
+#define libc_feupdateenv  libc_feupdateenv_vfp
+#define libc_feupdateenvf libc_feupdateenv_vfp
+#define libc_feupdateenvl libc_feupdateenv_vfp
+
+#define libc_feupdateenv_test  libc_feupdateenv_test_vfp
+#define libc_feupdateenv_testf libc_feupdateenv_test_vfp
+#define libc_feupdateenv_testl libc_feupdateenv_test_vfp
+
+/* We have support for rounding mode context.  */
+#define HAVE_RM_CTX 1
+
+#define libc_feholdsetround_ctx		libc_feholdsetround_vfp_ctx
+#define libc_feresetround_ctx		libc_feresetround_vfp_ctx
+#define libc_feresetround_noex_ctx	libc_fesetenv_vfp_ctx
+
+#define libc_feholdsetroundf_ctx	libc_feholdsetround_vfp_ctx
+#define libc_feresetroundf_ctx		libc_feresetround_vfp_ctx
+#define libc_feresetround_noexf_ctx	libc_fesetenv_vfp_ctx
+
+#define libc_feholdsetroundl_ctx	libc_feholdsetround_vfp_ctx
+#define libc_feresetroundl_ctx		libc_feresetround_vfp_ctx
+#define libc_feresetround_noexl_ctx	libc_fesetenv_vfp_ctx
+
+#endif /* CSKY_FENV_PRIVATE_H */