Provide x32 times

Since times returns 64-bit clock_t on x32, we need to provide x32 times
by redefining INTERNAL_SYSCALL_NCS and INTERNAL_SYSCALL_ERROR_P with
64-bit return type for syscall.  All system calls returning 64-bit
integer, which are lseek, time and times, must be handled specially for
x32.  lseek is handled by x32 lseek.S and time doesn't check syscall
return.  times is the only missed one.  Before this patch, there are

0000000 <__times>:
   0:	b8 64 00 00 40       	mov    $0x40000064,%eax
   5:	0f 05                	syscall
   7:	48 63 d0             	movslq %eax,%rdx
                                ^^^^^^^^^^ Incorrect signed extension
   a:	48 83 fa f2          	cmp    $0xfffffffffffffff2,%rdx
   e:	75 07                	jne    17 <__times+0x17>
  10:	3d 00 f0 ff ff       	cmp    $0xfffff000,%eax
                                ^^^^^^^^^^^^^^^^^^^^^ 32-bit compare
  15:	77 11                	ja     28 <__times+0x28>
  17:	48 83 fa ff          	cmp    $0xffffffffffffffff,%rdx
  1b:	b8 00 00 00 00       	mov    $0x0,%eax
  20:	48 0f 45 c2          	cmovne %rdx,%rax
  24:	c3                   	retq

After this patch, there are

00000000 <__times>:
   0:	b8 64 00 00 40       	mov    $0x40000064,%eax
   5:	0f 05                	syscall
   7:	48 83 f8 f2          	cmp    $0xfffffffffffffff2,%rax
   b:	75 08                	jne    15 <__times+0x15>
   d:	48 3d 00 f0 ff ff    	cmp    $0xfffffffffffff000,%rax
  13:	77 13                	ja     28 <__times+0x28>
  15:	48 83 f8 ff          	cmp    $0xffffffffffffffff,%rax
  19:	ba 00 00 00 00       	mov    $0x0,%edx
  1e:	48 0f 44 c2          	cmove  %rdx,%rax
  22:	c3                   	retq

The incorrect signed extension and 32-bit compare are gone.

	[BZ #19363]
	* sysdeps/unix/sysv/linux/x86_64/x32/times.c: New file.
This commit is contained in:
H.J. Lu 2015-12-17 11:46:49 -08:00
parent 2094350c9c
commit 8ead7a9b94
2 changed files with 43 additions and 0 deletions

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@ -1,3 +1,8 @@
2015-12-17 H.J. Lu <hongjiu.lu@intel.com>
[BZ #19363]
* sysdeps/unix/sysv/linux/x86_64/x32/times.c: New file.
2015-12-17 Adhemerval Zanella <adhemerval.zanella@linaro.org>
* sysdeps/powerpc/power7/fpu/s_logb.c (__logb): Fix return for

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@ -0,0 +1,38 @@
/* Linux times. X32 version.
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 <sysdep.h>
/* Linux times system call returns 64-bit integer. */
#undef INTERNAL_SYSCALL_NCS
#define INTERNAL_SYSCALL_NCS(name, err, nr, args...) \
({ \
unsigned long long int resultvar; \
LOAD_ARGS_##nr (args) \
LOAD_REGS_##nr \
asm volatile ( \
"syscall\n\t" \
: "=a" (resultvar) \
: "0" (name) ASM_ARGS_##nr : "memory", REGISTERS_CLOBBERED_BY_SYSCALL); \
(long long int) resultvar; })
#undef INTERNAL_SYSCALL_ERROR_P
#define INTERNAL_SYSCALL_ERROR_P(val, err) \
((unsigned long long int) (val) >= -4095LL)
#include <sysdeps/unix/sysv/linux/times.c>