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-rw-r--r--sysdeps/i386/fpu/fesetenv.c40
-rw-r--r--sysdeps/x86/fpu/Makefile3
-rw-r--r--sysdeps/x86/fpu/test-fenv-sse-2.c176
-rw-r--r--sysdeps/x86/fpu/test-fenv-x87.c169
-rw-r--r--sysdeps/x86_64/fpu/fesetenv.c40
5 files changed, 407 insertions, 21 deletions
diff --git a/sysdeps/i386/fpu/fesetenv.c b/sysdeps/i386/fpu/fesetenv.c
index 910aa0991c..f3b9cefee5 100644
--- a/sysdeps/i386/fpu/fesetenv.c
+++ b/sysdeps/i386/fpu/fesetenv.c
@@ -18,12 +18,18 @@
    <http://www.gnu.org/licenses/>.  */
 
 #include <fenv.h>
+#include <fpu_control.h>
 #include <assert.h>
 #include <unistd.h>
 #include <ldsodefs.h>
 #include <dl-procinfo.h>
 
 
+/* All exceptions, including the x86-specific "denormal operand"
+   exception.  */
+#define FE_ALL_EXCEPT_X86 (FE_ALL_EXCEPT | __FE_DENORM)
+
+
 int
 __fesetenv (const fenv_t *envp)
 {
@@ -40,22 +46,30 @@ __fesetenv (const fenv_t *envp)
 
   if (envp == FE_DFL_ENV)
     {
-      temp.__control_word |= FE_ALL_EXCEPT;
+      temp.__control_word |= FE_ALL_EXCEPT_X86;
       temp.__control_word &= ~FE_TOWARDZERO;
-      temp.__status_word &= ~FE_ALL_EXCEPT;
+      temp.__control_word |= _FPU_EXTENDED;
+      temp.__status_word &= ~FE_ALL_EXCEPT_X86;
     }
   else if (envp == FE_NOMASK_ENV)
     {
       temp.__control_word &= ~(FE_ALL_EXCEPT | FE_TOWARDZERO);
-      temp.__status_word &= ~FE_ALL_EXCEPT;
+      /* Keep the "denormal operand" exception masked.  */
+      temp.__control_word |= __FE_DENORM;
+      temp.__control_word |= _FPU_EXTENDED;
+      temp.__status_word &= ~FE_ALL_EXCEPT_X86;
     }
   else
     {
-      temp.__control_word &= ~(FE_ALL_EXCEPT | FE_TOWARDZERO);
+      temp.__control_word &= ~(FE_ALL_EXCEPT_X86
+			       | FE_TOWARDZERO
+			       | _FPU_EXTENDED);
       temp.__control_word |= (envp->__control_word
-			      & (FE_ALL_EXCEPT | FE_TOWARDZERO));
-      temp.__status_word &= ~FE_ALL_EXCEPT;
-      temp.__status_word |= envp->__status_word & FE_ALL_EXCEPT;
+			      & (FE_ALL_EXCEPT_X86
+				 | FE_TOWARDZERO
+				 | _FPU_EXTENDED));
+      temp.__status_word &= ~FE_ALL_EXCEPT_X86;
+      temp.__status_word |= envp->__status_word & FE_ALL_EXCEPT_X86;
     }
   temp.__eip = 0;
   temp.__cs_selector = 0;
@@ -73,22 +87,28 @@ __fesetenv (const fenv_t *envp)
       if (envp == FE_DFL_ENV)
 	{
 	  /* Clear SSE exceptions.  */
-	  mxcsr &= ~FE_ALL_EXCEPT;
+	  mxcsr &= ~FE_ALL_EXCEPT_X86;
 	  /* Set mask for SSE MXCSR.  */
-	  mxcsr |= (FE_ALL_EXCEPT << 7);
+	  mxcsr |= (FE_ALL_EXCEPT_X86 << 7);
 	  /* Set rounding to FE_TONEAREST.  */
 	  mxcsr &= ~0x6000;
 	  mxcsr |= (FE_TONEAREST << 3);
+	  /* Clear the FZ and DAZ bits.  */
+	  mxcsr &= ~0x8040;
 	}
       else if (envp == FE_NOMASK_ENV)
 	{
 	  /* Clear SSE exceptions.  */
-	  mxcsr &= ~FE_ALL_EXCEPT;
+	  mxcsr &= ~FE_ALL_EXCEPT_X86;
 	  /* Do not mask exceptions.  */
 	  mxcsr &= ~(FE_ALL_EXCEPT << 7);
+	  /* Keep the "denormal operand" exception masked.  */
+	  mxcsr |= (__FE_DENORM << 7);
 	  /* Set rounding to FE_TONEAREST.  */
 	  mxcsr &= ~0x6000;
 	  mxcsr |= (FE_TONEAREST << 3);
+	  /* Clear the FZ and DAZ bits.  */
+	  mxcsr &= ~0x8040;
 	}
       else
 	mxcsr = envp->__eip;
diff --git a/sysdeps/x86/fpu/Makefile b/sysdeps/x86/fpu/Makefile
index d38497cff3..b561995658 100644
--- a/sysdeps/x86/fpu/Makefile
+++ b/sysdeps/x86/fpu/Makefile
@@ -1,6 +1,7 @@
 ifeq ($(subdir),math)
 libm-support += powl_helper
-tests += test-fenv-sse test-fenv-clear-sse
+tests += test-fenv-sse test-fenv-clear-sse test-fenv-x87 test-fenv-sse-2
 CFLAGS-test-fenv-sse.c += -msse2 -mfpmath=sse
 CFLAGS-test-fenv-clear-sse.c += -msse2 -mfpmath=sse
+CFLAGS-test-fenv-sse-2.c += -msse2 -mfpmath=sse
 endif
diff --git a/sysdeps/x86/fpu/test-fenv-sse-2.c b/sysdeps/x86/fpu/test-fenv-sse-2.c
new file mode 100644
index 0000000000..12946e63ce
--- /dev/null
+++ b/sysdeps/x86/fpu/test-fenv-sse-2.c
@@ -0,0 +1,176 @@
+/* Test x86-specific floating-point environment (bug 16068): SSE part.
+   Copyright (C) 2015 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 <cpuid.h>
+#include <fenv.h>
+#include <float.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+
+static bool
+have_sse2 (void)
+{
+  unsigned int eax, ebx, ecx, edx;
+
+  if (!__get_cpuid (1, &eax, &ebx, &ecx, &edx))
+    return false;
+
+  return (edx & bit_SSE2) != 0;
+}
+
+static uint32_t
+get_sse_mxcsr (void)
+{
+  uint32_t temp;
+  __asm__ __volatile__ ("stmxcsr %0" : "=m" (temp));
+  return temp;
+}
+
+static void
+set_sse_mxcsr (uint32_t val)
+{
+  __asm__ __volatile__ ("ldmxcsr %0" : : "m" (val));
+}
+
+static void
+set_sse_mxcsr_bits (uint32_t mask, uint32_t bits)
+{
+  uint32_t mxcsr = get_sse_mxcsr ();
+  mxcsr = (mxcsr & ~mask) | bits;
+  set_sse_mxcsr (mxcsr);
+}
+
+static int
+test_sse_mxcsr_bits (const char *test, uint32_t mask, uint32_t bits)
+{
+  uint32_t mxcsr = get_sse_mxcsr ();
+  printf ("Testing %s: mxcsr = %x\n", test, mxcsr);
+  if ((mxcsr & mask) == bits)
+    {
+      printf ("PASS: %s\n", test);
+      return 0;
+    }
+  else
+    {
+      printf ("FAIL: %s\n", test);
+      return 1;
+    }
+}
+
+#define MXCSR_FZ 0x8000
+#define MXCSR_DAZ 0x40
+#define MXCSR_DE 0x2
+#define MXCSR_DM 0x100
+
+static __attribute__ ((noinline)) int
+sse_tests (void)
+{
+  int result = 0;
+  fenv_t env1, env2;
+  /* Test FZ bit.  */
+  fegetenv (&env1);
+  set_sse_mxcsr_bits (MXCSR_FZ, MXCSR_FZ);
+  fegetenv (&env2);
+  fesetenv (&env1);
+  result |= test_sse_mxcsr_bits ("fesetenv FZ restoration",
+				 MXCSR_FZ, 0);
+  set_sse_mxcsr_bits (MXCSR_FZ, 0);
+  fesetenv (&env2);
+  result |= test_sse_mxcsr_bits ("fesetenv FZ restoration 2",
+				 MXCSR_FZ, MXCSR_FZ);
+  set_sse_mxcsr_bits (MXCSR_FZ, MXCSR_FZ);
+  fesetenv (FE_NOMASK_ENV);
+  result |= test_sse_mxcsr_bits ("fesetenv (FE_NOMASK_ENV) FZ restoration",
+				 MXCSR_FZ, 0);
+  set_sse_mxcsr_bits (MXCSR_FZ, MXCSR_FZ);
+  fesetenv (FE_DFL_ENV);
+  result |= test_sse_mxcsr_bits ("fesetenv (FE_DFL_ENV) FZ restoration",
+				 MXCSR_FZ, 0);
+  /* Test DAZ bit.  */
+  set_sse_mxcsr_bits (MXCSR_DAZ, MXCSR_DAZ);
+  fegetenv (&env2);
+  fesetenv (&env1);
+  result |= test_sse_mxcsr_bits ("fesetenv DAZ restoration",
+				 MXCSR_DAZ, 0);
+  set_sse_mxcsr_bits (MXCSR_DAZ, 0);
+  fesetenv (&env2);
+  result |= test_sse_mxcsr_bits ("fesetenv DAZ restoration 2",
+				 MXCSR_DAZ, MXCSR_DAZ);
+  set_sse_mxcsr_bits (MXCSR_DAZ, MXCSR_DAZ);
+  fesetenv (FE_NOMASK_ENV);
+  result |= test_sse_mxcsr_bits ("fesetenv (FE_NOMASK_ENV) DAZ restoration",
+				 MXCSR_DAZ, 0);
+  set_sse_mxcsr_bits (MXCSR_DAZ, MXCSR_DAZ);
+  fesetenv (FE_DFL_ENV);
+  result |= test_sse_mxcsr_bits ("fesetenv (FE_DFL_ENV) DAZ restoration",
+				 MXCSR_DAZ, 0);
+  /* Test DM bit.  */
+  set_sse_mxcsr_bits (MXCSR_DM, 0);
+  fegetenv (&env2);
+  fesetenv (&env1);
+  result |= test_sse_mxcsr_bits ("fesetenv DM restoration",
+				 MXCSR_DM, MXCSR_DM);
+  set_sse_mxcsr_bits (MXCSR_DM, MXCSR_DM);
+  fesetenv (&env2);
+  result |= test_sse_mxcsr_bits ("fesetenv DM restoration 2",
+				 MXCSR_DM, 0);
+  set_sse_mxcsr_bits (MXCSR_DM, 0);
+  /* Presume FE_NOMASK_ENV should leave the "denormal operand"
+     exception masked, as not a standard exception.  */
+  fesetenv (FE_NOMASK_ENV);
+  result |= test_sse_mxcsr_bits ("fesetenv (FE_NOMASK_ENV) DM restoration",
+				 MXCSR_DM, MXCSR_DM);
+  set_sse_mxcsr_bits (MXCSR_DM, 0);
+  fesetenv (FE_DFL_ENV);
+  result |= test_sse_mxcsr_bits ("fesetenv (FE_DFL_ENV) DM restoration",
+				 MXCSR_DM, MXCSR_DM);
+  /* Test DE bit.  */
+  set_sse_mxcsr_bits (MXCSR_DE, MXCSR_DE);
+  fegetenv (&env2);
+  fesetenv (&env1);
+  result |= test_sse_mxcsr_bits ("fesetenv DE restoration",
+				 MXCSR_DE, 0);
+  set_sse_mxcsr_bits (MXCSR_DE, 0);
+  fesetenv (&env2);
+  result |= test_sse_mxcsr_bits ("fesetenv DE restoration 2",
+				 MXCSR_DE, MXCSR_DE);
+  set_sse_mxcsr_bits (MXCSR_DE, MXCSR_DE);
+  fesetenv (FE_NOMASK_ENV);
+  result |= test_sse_mxcsr_bits ("fesetenv (FE_NOMASK_ENV) DE restoration",
+				 MXCSR_DE, 0);
+  set_sse_mxcsr_bits (MXCSR_DE, MXCSR_DE);
+  fesetenv (FE_DFL_ENV);
+  result |= test_sse_mxcsr_bits ("fesetenv (FE_DFL_ENV) DE restoration",
+				 MXCSR_DE, 0);
+  return result;
+}
+
+static int
+do_test (void)
+{
+  if (!have_sse2 ())
+    {
+      puts ("CPU does not support SSE2, cannot test");
+      return 0;
+    }
+  return sse_tests ();
+}
+
+#define TEST_FUNCTION do_test ()
+#include <test-skeleton.c>
diff --git a/sysdeps/x86/fpu/test-fenv-x87.c b/sysdeps/x86/fpu/test-fenv-x87.c
new file mode 100644
index 0000000000..2f74471eac
--- /dev/null
+++ b/sysdeps/x86/fpu/test-fenv-x87.c
@@ -0,0 +1,169 @@
+/* Test x86-specific floating-point environment (bug 16068): x87 part.
+   Copyright (C) 2015 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 <float.h>
+#include <fpu_control.h>
+#include <stdint.h>
+#include <stdio.h>
+
+static uint16_t
+get_x87_cw (void)
+{
+  fpu_control_t cw;
+  _FPU_GETCW (cw);
+  return cw;
+}
+
+static void
+set_x87_cw (uint16_t val)
+{
+  fpu_control_t cw = val;
+  _FPU_SETCW (cw);
+}
+
+static void
+set_x87_cw_bits (uint16_t mask, uint16_t bits)
+{
+  uint16_t cw = get_x87_cw ();
+  cw = (cw & ~mask) | bits;
+  set_x87_cw (cw);
+}
+
+static int
+test_x87_cw_bits (const char *test, uint16_t mask, uint16_t bits)
+{
+  uint16_t cw = get_x87_cw ();
+  printf ("Testing %s: cw = %x\n", test, cw);
+  if ((cw & mask) == bits)
+    {
+      printf ("PASS: %s\n", test);
+      return 0;
+    }
+  else
+    {
+      printf ("FAIL: %s\n", test);
+      return 1;
+    }
+}
+
+static uint16_t
+get_x87_sw (void)
+{
+  uint16_t temp;
+  __asm__ __volatile__ ("fnstsw %0" : "=a" (temp));
+  return temp;
+}
+
+static void
+set_x87_sw_bits (uint16_t mask, uint16_t bits)
+{
+  fenv_t temp;
+  __asm__ __volatile__ ("fnstenv %0" : "=m" (temp));
+  temp.__status_word = (temp.__status_word & ~mask) | bits;
+  __asm__ __volatile__ ("fldenv %0" : : "m" (temp));
+}
+
+static int
+test_x87_sw_bits (const char *test, uint16_t mask, uint16_t bits)
+{
+  uint16_t sw = get_x87_sw ();
+  printf ("Testing %s: sw = %x\n", test, sw);
+  if ((sw & mask) == bits)
+    {
+      printf ("PASS: %s\n", test);
+      return 0;
+    }
+  else
+    {
+      printf ("FAIL: %s\n", test);
+      return 1;
+    }
+}
+
+#define X87_CW_PREC_MASK _FPU_EXTENDED
+
+static int
+do_test (void)
+{
+  int result = 0;
+  fenv_t env1, env2;
+  /* Test precision mask.  */
+  fegetenv (&env1);
+  set_x87_cw_bits (X87_CW_PREC_MASK, _FPU_SINGLE);
+  fegetenv (&env2);
+  fesetenv (&env1);
+  result |= test_x87_cw_bits ("fesetenv precision restoration",
+			      X87_CW_PREC_MASK, _FPU_EXTENDED);
+  set_x87_cw_bits (X87_CW_PREC_MASK, _FPU_EXTENDED);
+  fesetenv (&env2);
+  result |= test_x87_cw_bits ("fesetenv precision restoration 2",
+			      X87_CW_PREC_MASK, _FPU_SINGLE);
+  set_x87_cw_bits (X87_CW_PREC_MASK, _FPU_DOUBLE);
+  fesetenv (FE_NOMASK_ENV);
+  result |= test_x87_cw_bits ("fesetenv (FE_NOMASK_ENV) precision restoration",
+			      X87_CW_PREC_MASK, _FPU_EXTENDED);
+  set_x87_cw_bits (X87_CW_PREC_MASK, _FPU_SINGLE);
+  fesetenv (FE_DFL_ENV);
+  result |= test_x87_cw_bits ("fesetenv (FE_DFL_ENV) precision restoration",
+			      X87_CW_PREC_MASK, _FPU_EXTENDED);
+  /* Test x87 denormal operand masking.  */
+  set_x87_cw_bits (_FPU_MASK_DM, 0);
+  fegetenv (&env2);
+  fesetenv (&env1);
+  result |= test_x87_cw_bits ("fesetenv denormal mask restoration",
+			      _FPU_MASK_DM, _FPU_MASK_DM);
+  set_x87_cw_bits (_FPU_MASK_DM, _FPU_MASK_DM);
+  fesetenv (&env2);
+  result |= test_x87_cw_bits ("fesetenv denormal mask restoration 2",
+			      _FPU_MASK_DM, 0);
+  set_x87_cw_bits (_FPU_MASK_DM, 0);
+  /* Presume FE_NOMASK_ENV should leave the "denormal operand"
+     exception masked, as not a standard exception.  */
+  fesetenv (FE_NOMASK_ENV);
+  result |= test_x87_cw_bits ("fesetenv (FE_NOMASK_ENV) denormal mask "
+			      "restoration",
+			      _FPU_MASK_DM, _FPU_MASK_DM);
+  set_x87_cw_bits (_FPU_MASK_DM, 0);
+  fesetenv (FE_DFL_ENV);
+  result |= test_x87_cw_bits ("fesetenv (FE_DFL_ENV) denormal mask "
+			      "restoration",
+			      _FPU_MASK_DM, _FPU_MASK_DM);
+  /* Test x87 denormal operand exception.  */
+  set_x87_sw_bits (__FE_DENORM, __FE_DENORM);
+  fegetenv (&env2);
+  fesetenv (&env1);
+  result |= test_x87_sw_bits ("fesetenv denormal exception restoration",
+			      __FE_DENORM, 0);
+  set_x87_sw_bits (__FE_DENORM, 0);
+  fesetenv (&env2);
+  result |= test_x87_sw_bits ("fesetenv denormal exception restoration 2",
+			      __FE_DENORM, __FE_DENORM);
+  set_x87_sw_bits (__FE_DENORM, __FE_DENORM);
+  fesetenv (FE_NOMASK_ENV);
+  result |= test_x87_sw_bits ("fesetenv (FE_NOMASK_ENV) exception restoration",
+			      __FE_DENORM, 0);
+  set_x87_sw_bits (__FE_DENORM, __FE_DENORM);
+  fesetenv (FE_DFL_ENV);
+  result |= test_x87_sw_bits ("fesetenv (FE_DFL_ENV) exception restoration",
+			      __FE_DENORM, 0);
+  return result;
+}
+
+#define TEST_FUNCTION do_test ()
+#include <test-skeleton.c>
diff --git a/sysdeps/x86_64/fpu/fesetenv.c b/sysdeps/x86_64/fpu/fesetenv.c
index 9950aa734a..381540f687 100644
--- a/sysdeps/x86_64/fpu/fesetenv.c
+++ b/sysdeps/x86_64/fpu/fesetenv.c
@@ -17,9 +17,15 @@
    <http://www.gnu.org/licenses/>.  */
 
 #include <fenv.h>
+#include <fpu_control.h>
 #include <assert.h>
 
 
+/* All exceptions, including the x86-specific "denormal operand"
+   exception.  */
+#define FE_ALL_EXCEPT_X86 (FE_ALL_EXCEPT | __FE_DENORM)
+
+
 int
 __fesetenv (const fenv_t *envp)
 {
@@ -34,47 +40,61 @@ __fesetenv (const fenv_t *envp)
 
   if (envp == FE_DFL_ENV)
     {
-      temp.__control_word |= FE_ALL_EXCEPT;
+      temp.__control_word |= FE_ALL_EXCEPT_X86;
       temp.__control_word &= ~FE_TOWARDZERO;
-      temp.__status_word &= ~FE_ALL_EXCEPT;
+      temp.__control_word |= _FPU_EXTENDED;
+      temp.__status_word &= ~FE_ALL_EXCEPT_X86;
       temp.__eip = 0;
       temp.__cs_selector = 0;
       temp.__opcode = 0;
       temp.__data_offset = 0;
       temp.__data_selector = 0;
       /* Clear SSE exceptions.  */
-      temp.__mxcsr &= ~FE_ALL_EXCEPT;
+      temp.__mxcsr &= ~FE_ALL_EXCEPT_X86;
       /* Set mask for SSE MXCSR.  */
-      temp.__mxcsr |= (FE_ALL_EXCEPT << 7);
+      temp.__mxcsr |= (FE_ALL_EXCEPT_X86 << 7);
       /* Set rounding to FE_TONEAREST.  */
       temp.__mxcsr &= ~ 0x6000;
       temp.__mxcsr |= (FE_TONEAREST << 3);
+      /* Clear the FZ and DAZ bits.  */
+      temp.__mxcsr &= ~0x8040;
     }
   else if (envp == FE_NOMASK_ENV)
     {
       temp.__control_word &= ~(FE_ALL_EXCEPT | FE_TOWARDZERO);
-      temp.__status_word &= ~FE_ALL_EXCEPT;
+      /* Keep the "denormal operand" exception masked.  */
+      temp.__control_word |= __FE_DENORM;
+      temp.__control_word |= _FPU_EXTENDED;
+      temp.__status_word &= ~FE_ALL_EXCEPT_X86;
       temp.__eip = 0;
       temp.__cs_selector = 0;
       temp.__opcode = 0;
       temp.__data_offset = 0;
       temp.__data_selector = 0;
       /* Clear SSE exceptions.  */
-      temp.__mxcsr &= ~FE_ALL_EXCEPT;
+      temp.__mxcsr &= ~FE_ALL_EXCEPT_X86;
       /* Set mask for SSE MXCSR.  */
       /* Set rounding to FE_TONEAREST.  */
       temp.__mxcsr &= ~ 0x6000;
       temp.__mxcsr |= (FE_TONEAREST << 3);
       /* Do not mask exceptions.  */
       temp.__mxcsr &= ~(FE_ALL_EXCEPT << 7);
+      /* Keep the "denormal operand" exception masked.  */
+      temp.__mxcsr |= (__FE_DENORM << 7);
+      /* Clear the FZ and DAZ bits.  */
+      temp.__mxcsr &= ~0x8040;
     }
   else
     {
-      temp.__control_word &= ~(FE_ALL_EXCEPT | FE_TOWARDZERO);
+      temp.__control_word &= ~(FE_ALL_EXCEPT_X86
+			       | FE_TOWARDZERO
+			       | _FPU_EXTENDED);
       temp.__control_word |= (envp->__control_word
-			      & (FE_ALL_EXCEPT | FE_TOWARDZERO));
-      temp.__status_word &= ~FE_ALL_EXCEPT;
-      temp.__status_word |= envp->__status_word & FE_ALL_EXCEPT;
+			      & (FE_ALL_EXCEPT_X86
+				 | FE_TOWARDZERO
+				 | _FPU_EXTENDED));
+      temp.__status_word &= ~FE_ALL_EXCEPT_X86;
+      temp.__status_word |= envp->__status_word & FE_ALL_EXCEPT_X86;
       temp.__eip = envp->__eip;
       temp.__cs_selector = envp->__cs_selector;
       temp.__opcode = envp->__opcode;