csky: add fenv support from glibcHEADmaster

1 files changed, 122 insertions, 0 deletions

diff --git a/libm/csky/fraiseexcpt.c b/libm/csky/fraiseexcpt.c
new file mode 100644
index 000000000..31cd32f2c
--- /dev/null
+++ b/libm/csky/fraiseexcpt.c
@@ -0,0 +1,122 @@
+/* Raise given exceptions.
+   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/>.  */
+
+#include <fenv.h>
+#include "fenv_libc.h"
+#include <fpu_control.h>
+#include <float.h>
+#include <math.h>
+
+int
+feraiseexcept (int excepts)
+{
+    /* Raise exceptions represented by EXCEPTS.  But we must raise only one
+     signal at a time.  It is important that if the overflow/underflow
+     exception and the divide by zero exception are given at the same
+     time, the overflow/underflow exception follows the divide by zero
+     exception.  */
+
+# ifndef __csky_fpuv1__
+    /* First: invalid exception.  */
+    if (FE_INVALID & excepts)
+    {
+      /* One example of a invalid operation is 0 * Infinity.  */
+      float x = HUGE_VALF, y = 0.0f;
+      __asm__ __volatile__ ("fmuls %0, %0, %1" : "+v" (x) : "v" (y));
+    }
+
+    /* Next: division by zero.  */
+    if (FE_DIVBYZERO & excepts)
+    {
+      float x = 1.0f, y = 0.0f;
+      __asm__ __volatile__ ("fdivs %0, %0, %1" : "+v" (x) : "v" (y));
+    }
+
+    /* Next: overflow.  */
+    if (FE_OVERFLOW & excepts)
+    {
+      float x = FLT_MAX;
+      __asm__ __volatile__ ("fmuls %0, %0, %0" : "+v" (x));
+    }
+    /* Next: underflow.  */
+    if (FE_UNDERFLOW & excepts)
+    {
+      float x = -FLT_MIN;
+
+      __asm__ __volatile__ ("fmuls %0, %0, %0" : "+v" (x));
+    }
+
+    /* Last: inexact.  */
+    if (FE_INEXACT & excepts)
+    {
+      float x = 1.0f, y = 3.0f;
+      __asm__ __volatile__ ("fdivs %0, %0, %1" : "+v" (x) : "v" (y));
+    }
+
+    if (__FE_DENORMAL & excepts)
+    {
+      double x = 4.9406564584124654e-324;
+      __asm__ __volatile__ ("fstod %0, %0" : "+v" (x));
+    }
+# else
+     int tmp = 0;
+    /* First: invalid exception.  */
+    if (FE_INVALID & excepts)
+    {
+      /* One example of a invalid operation is 0 * Infinity.  */
+      float x = HUGE_VALF, y = 0.0f;
+      __asm__ __volatile__ ("fmuls %0, %0, %2, %1"
+                    : "+f" (x), "+r"(tmp) : "f" (y));
+    }
+
+    /* Next: division by zero.  */
+    if (FE_DIVBYZERO & excepts)
+    {
+      float x = 1.0f, y = 0.0f;
+      __asm__ __volatile__ ("fdivs %0, %0, %2, %1"
+                    : "+f" (x), "+r"(tmp) : "f" (y));
+    }
+
+    /* Next: overflow.  */
+    if (FE_OVERFLOW & excepts)
+    {
+      float x = FLT_MAX, y = FLT_MAX;
+      __asm__ __volatile__ ("fmuls %0, %0, %2, %1"
+                    : "+f" (x), "+r"(tmp) : "f" (y));
+    }
+
+    /* Next: underflow.  */
+    if (FE_UNDERFLOW & excepts)
+    {
+      float x = -FLT_MIN, y = -FLT_MIN;
+
+      __asm__ __volatile__ ("fmuls %0, %0, %2, %1"
+                    : "+f" (x), "+r"(tmp) : "f" (y));
+    }
+
+    /* Last: inexact.  */
+    if (FE_INEXACT & excepts)
+    {
+      float x = 1.0f, y = 3.0f;
+      __asm__ __volatile__ ("fdivs %0, %0, %2, %1"
+                    : "+f" (x), "+r"(tmp) : "f" (y));
+    }
+# endif /* __csky_fpuv2__ */
+
+    /* Success.  */
+    return 0;
+}