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authorZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
committerZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
commit5046dbb4a7eba5eccfd258f92f4735c9ffc8d069 (patch)
tree4470480d904b65cf14ca524f96f79eca818c3eaf /REORG.TODO/sysdeps/x86_64/fpu/fraiseexcpt.c
parent199fc19d3aaaf57944ef036e15904febe877fc93 (diff)
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Prepare for radical source tree reorganization. zack/build-layout-experiment
All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).
Diffstat (limited to 'REORG.TODO/sysdeps/x86_64/fpu/fraiseexcpt.c')
-rw-r--r--REORG.TODO/sysdeps/x86_64/fpu/fraiseexcpt.c121
1 files changed, 121 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/x86_64/fpu/fraiseexcpt.c b/REORG.TODO/sysdeps/x86_64/fpu/fraiseexcpt.c
new file mode 100644
index 0000000000..13eb4af331
--- /dev/null
+++ b/REORG.TODO/sysdeps/x86_64/fpu/fraiseexcpt.c
@@ -0,0 +1,121 @@
+/* Raise given exceptions.
+   Copyright (C) 2001-2017 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.h>
+
+int
+__feraiseexcept (int excepts)
+{
+  /* 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) != 0)
+    {
+      /* One example of an invalid operation is 0.0 / 0.0.  */
+      float f = 0.0;
+
+      __asm__ __volatile__ ("divss %0, %0 " : : "x" (f));
+      (void) &f;
+    }
+
+  /* Next: division by zero.  */
+  if ((FE_DIVBYZERO & excepts) != 0)
+    {
+      float f = 1.0;
+      float g = 0.0;
+
+      __asm__ __volatile__ ("divss %1, %0" : : "x" (f), "x" (g));
+      (void) &f;
+    }
+
+  /* Next: overflow.  */
+  if ((FE_OVERFLOW & excepts) != 0)
+    {
+      /* XXX: Is it ok to only set the x87 FPU?  */
+      /* There is no way to raise only the overflow flag.  Do it the
+	 hard way.  */
+      fenv_t temp;
+
+      /* Bah, we have to clear selected exceptions.  Since there is no
+	 `fldsw' instruction we have to do it the hard way.  */
+      __asm__ __volatile__ ("fnstenv %0" : "=m" (*&temp));
+
+      /* Set the relevant bits.  */
+      temp.__status_word |= FE_OVERFLOW;
+
+      /* Put the new data in effect.  */
+      __asm__ __volatile__ ("fldenv %0" : : "m" (*&temp));
+
+      /* And raise the exception.  */
+      __asm__ __volatile__ ("fwait");
+    }
+
+  /* Next: underflow.  */
+  if ((FE_UNDERFLOW & excepts) != 0)
+    {
+      /* XXX: Is it ok to only set the x87 FPU?  */
+      /* There is no way to raise only the underflow flag.  Do it the
+	 hard way.  */
+      fenv_t temp;
+
+      /* Bah, we have to clear selected exceptions.  Since there is no
+	 `fldsw' instruction we have to do it the hard way.  */
+      __asm__ __volatile__ ("fnstenv %0" : "=m" (*&temp));
+
+      /* Set the relevant bits.  */
+      temp.__status_word |= FE_UNDERFLOW;
+
+      /* Put the new data in effect.  */
+      __asm__ __volatile__ ("fldenv %0" : : "m" (*&temp));
+
+      /* And raise the exception.  */
+      __asm__ __volatile__ ("fwait");
+    }
+
+  /* Last: inexact.  */
+  if ((FE_INEXACT & excepts) != 0)
+    {
+      /* XXX: Is it ok to only set the x87 FPU?  */
+      /* There is no way to raise only the inexact flag.  Do it the
+	 hard way.  */
+      fenv_t temp;
+
+      /* Bah, we have to clear selected exceptions.  Since there is no
+	 `fldsw' instruction we have to do it the hard way.  */
+      __asm__ __volatile__ ("fnstenv %0" : "=m" (*&temp));
+
+      /* Set the relevant bits.  */
+      temp.__status_word |= FE_INEXACT;
+
+      /* Put the new data in effect.  */
+      __asm__ __volatile__ ("fldenv %0" : : "m" (*&temp));
+
+      /* And raise the exception.  */
+      __asm__ __volatile__ ("fwait");
+    }
+
+  /* Success.  */
+  return 0;
+}
+libm_hidden_def (__feraiseexcept)
+weak_alias (__feraiseexcept, feraiseexcept)
+libm_hidden_weak (feraiseexcept)