public inbox for glibc-cvs@sourceware.org
help / color / mirror / Atom feed
* [glibc] math: x86 ceill traps when FE_INEXACT is enabled (BZ 31600)
@ 2024-04-04 17:36 Adhemerval Zanella
0 siblings, 0 replies; only message in thread
From: Adhemerval Zanella @ 2024-04-04 17:36 UTC (permalink / raw)
To: glibc-cvs
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=637bfc392f406c6c77f59494ed34949a6161bceb
commit 637bfc392f406c6c77f59494ed34949a6161bceb
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Wed Apr 3 16:39:17 2024 -0300
math: x86 ceill traps when FE_INEXACT is enabled (BZ 31600)
The implementations of ceil functions using x87 floating point (i386 and
x86_64 long double only) traps when FE_INEXACT is enabled. Although
this is a GNU extension outside the scope of the C standard, other
architectures that also support traps do not show this behavior.
The fix moves the implementation to a common one that holds any
exceptions with a 'fnclex' (libc_feholdexcept_setround_387).
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
Diff:
---
math/Makefile | 3 ++
math/test-ceil-except-2.c | 67 +++++++++++++++++++++++++++++
sysdeps/i386/fpu/s_ceil.S | 34 ---------------
sysdeps/i386/fpu/s_ceil.c | 25 +++++++++++
sysdeps/i386/fpu/s_ceilf.S | 34 ---------------
sysdeps/i386/fpu/s_ceilf.c | 25 +++++++++++
sysdeps/i386/fpu/s_ceill.S | 39 -----------------
sysdeps/x86/fpu/s_ceill.c | 25 +++++++++++
sysdeps/x86/fpu/s_nearestint_387_template.c | 36 ++++++++++++++++
sysdeps/x86_64/fpu/s_ceill.S | 34 ---------------
10 files changed, 181 insertions(+), 141 deletions(-)
diff --git a/math/Makefile b/math/Makefile
index 121a709121..d2a740eebe 100644
--- a/math/Makefile
+++ b/math/Makefile
@@ -498,6 +498,7 @@ tests = \
bug-nextafter \
bug-nexttoward \
bug-tgmath1 \
+ test-ceil-except-2 \
test-femode \
test-femode-traps \
test-fenv basic-test \
@@ -989,6 +990,8 @@ CFLAGS-test-fe-snans-always-signal.c += $(config-cflags-signaling-nans)
CFLAGS-test-nan-const.c += -fno-builtin
+CFLAGS-test-ceil-except-2.c += -fno-builtin
+
include ../Rules
gen-all-calls = $(gen-libm-calls) $(gen-calls)
diff --git a/math/test-ceil-except-2.c b/math/test-ceil-except-2.c
new file mode 100644
index 0000000000..394a272d89
--- /dev/null
+++ b/math/test-ceil-except-2.c
@@ -0,0 +1,67 @@
+/* Test ceil functions do not disable exception traps.
+ Copyright (C) 2024 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 <math.h>
+#include <stdio.h>
+
+#ifndef FE_INEXACT
+# define FE_INEXACT 0
+#endif
+
+#define TEST_FUNC(NAME, FLOAT, SUFFIX) \
+static int \
+NAME (void) \
+{ \
+ int result = 0; \
+ volatile FLOAT a, b __attribute__ ((unused)); \
+ a = 1.5; \
+ /* ceil must work when traps on "inexact" are enabled. */ \
+ b = ceil ## SUFFIX (a); \
+ /* And it must have left those traps enabled. */ \
+ if (fegetexcept () == FE_INEXACT) \
+ puts ("PASS: " #FLOAT); \
+ else \
+ { \
+ puts ("FAIL: " #FLOAT); \
+ result = 1; \
+ } \
+ return result; \
+}
+
+TEST_FUNC (float_test, float, f)
+TEST_FUNC (double_test, double, )
+TEST_FUNC (ldouble_test, long double, l)
+
+static int
+do_test (void)
+{
+ if (feenableexcept (FE_INEXACT) == -1)
+ {
+ puts ("enabling FE_INEXACT traps failed, cannot test");
+ return 77;
+ }
+ int result = float_test ();
+ feenableexcept (FE_INEXACT);
+ result |= double_test ();
+ feenableexcept (FE_INEXACT);
+ result |= ldouble_test ();
+ return result;
+}
+
+#include <support/test-driver.c>
diff --git a/sysdeps/i386/fpu/s_ceil.S b/sysdeps/i386/fpu/s_ceil.S
deleted file mode 100644
index 99984f9b8d..0000000000
--- a/sysdeps/i386/fpu/s_ceil.S
+++ /dev/null
@@ -1,34 +0,0 @@
-/*
- * Public domain.
- */
-
-#include <machine/asm.h>
-#include <libm-alias-double.h>
-
-RCSID("$NetBSD: s_ceil.S,v 1.4 1995/05/08 23:52:13 jtc Exp $")
-
-ENTRY(__ceil)
- fldl 4(%esp)
- subl $32,%esp
- cfi_adjust_cfa_offset (32)
-
- fnstenv 4(%esp) /* store fpu environment */
-
- /* We use here %edx although only the low 1 bits are defined.
- But none of the operations should care and they are faster
- than the 16 bit operations. */
- movl $0x0800,%edx /* round towards +oo */
- orl 4(%esp),%edx
- andl $0xfbff,%edx
- movl %edx,(%esp)
- fldcw (%esp) /* load modified control word */
-
- frndint /* round */
-
- fldenv 4(%esp) /* restore original environment */
-
- addl $32,%esp
- cfi_adjust_cfa_offset (-32)
- ret
-END (__ceil)
-libm_alias_double (__ceil, ceil)
diff --git a/sysdeps/i386/fpu/s_ceil.c b/sysdeps/i386/fpu/s_ceil.c
new file mode 100644
index 0000000000..349135c5d3
--- /dev/null
+++ b/sysdeps/i386/fpu/s_ceil.c
@@ -0,0 +1,25 @@
+/* Return smallest integral value not less than argument. i386 version.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <libm-alias-double.h>
+
+#define FUNC __ceil
+#define TYPE double
+#define FE_OPTION FE_UPWARD
+#include "s_nearestint_387_template.c"
+libm_alias_double (__ceil, ceil)
diff --git a/sysdeps/i386/fpu/s_ceilf.S b/sysdeps/i386/fpu/s_ceilf.S
deleted file mode 100644
index 03e8e22609..0000000000
--- a/sysdeps/i386/fpu/s_ceilf.S
+++ /dev/null
@@ -1,34 +0,0 @@
-/*
- * Public domain.
- */
-
-#include <machine/asm.h>
-#include <libm-alias-float.h>
-
-RCSID("$NetBSD: s_ceilf.S,v 1.3 1995/05/08 23:52:44 jtc Exp $")
-
-ENTRY(__ceilf)
- flds 4(%esp)
- subl $32,%esp
- cfi_adjust_cfa_offset (32)
-
- fnstenv 4(%esp) /* store fpu environment */
-
- /* We use here %edx although only the low 1 bits are defined.
- But none of the operations should care and they are faster
- than the 16 bit operations. */
- movl $0x0800,%edx /* round towards +oo */
- orl 4(%esp),%edx
- andl $0xfbff,%edx
- movl %edx,(%esp)
- fldcw (%esp) /* load modified control word */
-
- frndint /* round */
-
- fldenv 4(%esp) /* restore original environment */
-
- addl $32,%esp
- cfi_adjust_cfa_offset (-32)
- ret
-END (__ceilf)
-libm_alias_float (__ceil, ceil)
diff --git a/sysdeps/i386/fpu/s_ceilf.c b/sysdeps/i386/fpu/s_ceilf.c
new file mode 100644
index 0000000000..e73a20fd71
--- /dev/null
+++ b/sysdeps/i386/fpu/s_ceilf.c
@@ -0,0 +1,25 @@
+/* Return largest integral value not less than argument. i386 version.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <libm-alias-float.h>
+
+#define FUNC __ceilf
+#define TYPE float
+#define FE_OPTION FE_UPWARD
+#include "s_nearestint_387_template.c"
+libm_alias_float (__ceil, ceil)
diff --git a/sysdeps/i386/fpu/s_ceill.S b/sysdeps/i386/fpu/s_ceill.S
deleted file mode 100644
index a551fce7f9..0000000000
--- a/sysdeps/i386/fpu/s_ceill.S
+++ /dev/null
@@ -1,39 +0,0 @@
-/*
- * Public domain.
- */
-
-#include <libm-alias-ldouble.h>
-#include <machine/asm.h>
-
-RCSID("$NetBSD: $")
-
-ENTRY(__ceill)
- fldt 4(%esp)
- subl $32,%esp
- cfi_adjust_cfa_offset (32)
-
- fnstenv 4(%esp) /* store fpu environment */
-
- /* We use here %edx although only the low 1 bits are defined.
- But none of the operations should care and they are faster
- than the 16 bit operations. */
- movl $0x0800,%edx /* round towards +oo */
- orl 4(%esp),%edx
- andl $0xfbff,%edx
- movl %edx,(%esp)
- fldcw (%esp) /* load modified control word */
-
- frndint /* round */
-
- /* Preserve "invalid" exceptions from sNaN input. */
- fnstsw
- andl $0x1, %eax
- orl %eax, 8(%esp)
-
- fldenv 4(%esp) /* restore original environment */
-
- addl $32,%esp
- cfi_adjust_cfa_offset (-32)
- ret
-END (__ceill)
-libm_alias_ldouble (__ceil, ceil)
diff --git a/sysdeps/x86/fpu/s_ceill.c b/sysdeps/x86/fpu/s_ceill.c
new file mode 100644
index 0000000000..860dd2c960
--- /dev/null
+++ b/sysdeps/x86/fpu/s_ceill.c
@@ -0,0 +1,25 @@
+/* Return smallest integral value not less than argument. x86 version.
+ Copyright (C) 2024 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 <libm-alias-ldouble.h>
+
+#define FUNC __ceill
+#define TYPE long double
+#define FE_OPTION FE_UPWARD
+#include "s_nearestint_387_template.c"
+libm_alias_ldouble (__ceil, ceil)
diff --git a/sysdeps/x86/fpu/s_nearestint_387_template.c b/sysdeps/x86/fpu/s_nearestint_387_template.c
new file mode 100644
index 0000000000..95fca93f87
--- /dev/null
+++ b/sysdeps/x86/fpu/s_nearestint_387_template.c
@@ -0,0 +1,36 @@
+/* Nearest integet template for x86.
+ Copyright (C) 2024 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/>. */
+
+#define NO_MATH_REDIRECT
+#include <math.h>
+#include <fenv_private.h>
+
+TYPE
+FUNC (TYPE x)
+{
+ fenv_t fenv;
+ TYPE r;
+
+ libc_feholdexcept_setround_387 (&fenv, FE_OPTION);
+ asm volatile ("frndint" : "=t" (r) : "0" (x));
+ /* Preserve "invalid" exceptions from sNaN input. */
+ fenv.__status_word |= libc_fetestexcept_387 (FE_INVALID);
+ libc_fesetenv_387 (&fenv);
+
+ return r;
+}
diff --git a/sysdeps/x86_64/fpu/s_ceill.S b/sysdeps/x86_64/fpu/s_ceill.S
deleted file mode 100644
index 16dbecd56d..0000000000
--- a/sysdeps/x86_64/fpu/s_ceill.S
+++ /dev/null
@@ -1,34 +0,0 @@
-/*
- * Public domain.
- */
-
-#include <libm-alias-ldouble.h>
-#include <machine/asm.h>
-
-
-ENTRY(__ceill)
- fldt 8(%rsp)
-
- fnstenv -28(%rsp) /* store fpu environment */
-
- /* We use here %edx although only the low 1 bits are defined.
- But none of the operations should care and they are faster
- than the 16 bit operations. */
- movl $0x0800,%edx /* round towards +oo */
- orl -28(%rsp),%edx
- andl $0xfbff,%edx
- movl %edx,-32(%rsp)
- fldcw -32(%rsp) /* load modified control word */
-
- frndint /* round */
-
- /* Preserve "invalid" exceptions from sNaN input. */
- fnstsw
- andl $0x1, %eax
- orl %eax, -24(%rsp)
-
- fldenv -28(%rsp) /* restore original environment */
-
- ret
-END (__ceill)
-libm_alias_ldouble (__ceil, ceil)
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2024-04-04 17:36 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2024-04-04 17:36 [glibc] math: x86 ceill traps when FE_INEXACT is enabled (BZ 31600) Adhemerval Zanella
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).