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authorH.J. Lu <hjl.tools@gmail.com>2015-08-21 04:46:39 -0700
committerH.J. Lu <hjl.tools@gmail.com>2015-08-21 04:46:53 -0700
commit0c5b8b5941e036dcaac69cecee9f01fdf9218e6e (patch)
tree3c147bf3d4f07169bc0812858d0c108773e575cd /sysdeps/unix/sysv/linux/faccessat.c
parent8d9e08981e1ac5ee90209adb3042206e9fffd286 (diff)
downloadglibc-0c5b8b5941e036dcaac69cecee9f01fdf9218e6e.tar.gz
Add INLINE_SYSCALL_RETURN/INLINE_SYSCALL_ERROR_RETURN
For ia32 PIC, the first thing of many syscalls does is to call __x86.get_pc_thunk.reg to load PC into reg in case there is an error, which is required for setting errno. In most cases, there are no errors. But we still call __x86.get_pc_thunk.reg. This patch adds INLINE_SYSCALL_RETURN and INLINE_SYSCALL_ERROR_RETURN so that i386 can optimize setting errno by branching to the internal __syscall_error without PLT. INLINE_SYSCALL_ERROR_RETURN is designed to take the negative error number returned from the majority of Linux kernels for which negating is a no-op with INTERNAL_SYSCALL_ERRNO. With i386 INLINE_SYSCALL_RETURN, INLINE_SYSCALL_ERROR_RETURN and i386 syscall inlining optimization for GCC 5, for sysdeps/unix/sysv/linux/fchmodat.c with -O2 -march=i686 -mtune=generic, GCC 5.2 now generates: <fchmodat>: 0: push %ebx 1: mov 0x14(%esp),%eax 5: mov 0x8(%esp),%ebx 9: mov 0xc(%esp),%ecx d: mov 0x10(%esp),%edx 11: test $0xfffffeff,%eax 16: jne 38 <fchmodat+0x38> 18: test $0x1,%ah 1b: jne 48 <fchmodat+0x48> 1d: mov $0x132,%eax 22: call *%gs:0x10 29: cmp $0xfffff000,%eax 2e: ja 58 <fchmodat+0x58> 30: pop %ebx 31: ret 32: lea 0x0(%esi),%esi 38: pop %ebx 39: mov $0xffffffea,%eax 3e: jmp 3f <fchmodat+0x3f> 3f: R_386_PC32 __syscall_error 43: nop 44: lea 0x0(%esi,%eiz,1),%esi 48: pop %ebx 49: mov $0xffffffa1,%eax 4e: jmp 4f <fchmodat+0x4f> 4f: R_386_PC32 __syscall_error 53: nop 54: lea 0x0(%esi,%eiz,1),%esi 58: pop %ebx 59: jmp 5a <fchmodat+0x5a> 5a: R_386_PC32 __syscall_error instead of <fchmodat>: 0: sub $0x8,%esp 3: mov 0x18(%esp),%eax 7: mov %ebx,(%esp) a: call b <fchmodat+0xb> b: R_386_PC32 __x86.get_pc_thunk.bx f: add $0x2,%ebx 11: R_386_GOTPC _GLOBAL_OFFSET_TABLE_ 15: mov %edi,0x4(%esp) 19: test $0xfffffeff,%eax 1e: jne 70 <fchmodat+0x70> 20: test $0x1,%ah 23: jne 88 <fchmodat+0x88> 25: mov 0x14(%esp),%edx 29: mov 0x10(%esp),%ecx 2d: mov 0xc(%esp),%edi 31: xchg %ebx,%edi 33: mov $0x132,%eax 38: call *%gs:0x10 3f: xchg %edi,%ebx 41: cmp $0xfffff000,%eax 46: ja 58 <fchmodat+0x58> 48: mov (%esp),%ebx 4b: mov 0x4(%esp),%edi 4f: add $0x8,%esp 52: ret 53: nop 54: lea 0x0(%esi,%eiz,1),%esi 58: mov 0x0(%ebx),%edx 5a: R_386_TLS_GOTIE __libc_errno 5e: neg %eax 60: mov %eax,%gs:(%edx) 63: mov $0xffffffff,%eax 68: jmp 48 <fchmodat+0x48> 6a: lea 0x0(%esi),%esi 70: mov 0x0(%ebx),%eax 72: R_386_TLS_GOTIE __libc_errno 76: movl $0x16,%gs:(%eax) 7d: mov $0xffffffff,%eax 82: jmp 48 <fchmodat+0x48> 84: lea 0x0(%esi,%eiz,1),%esi 88: mov 0x0(%ebx),%eax 8a: R_386_TLS_GOTIE __libc_errno 8e: movl $0x5f,%gs:(%eax) 95: mov $0xffffffff,%eax 9a: jmp 48 <fchmodat+0x48> * sysdeps/unix/sysdep.h (INLINE_SYSCALL_RETURN): New. (INLINE_SYSCALL_ERROR_RETURN): Likewise. * sysdeps/unix/sysv/linux/adjtime.c (ADJTIME): Use INLINE_SYSCALL_RETURN and INLINE_SYSCALL_ERROR_RETURN. * sysdeps/unix/sysv/linux/aio_sigqueue.c (__aio_sigqueue): Likewise. * sysdeps/unix/sysv/linux/dl-openat64.c (openat64): Likewise. * sysdeps/unix/sysv/linux/eventfd.c (eventfd): Likewise. * sysdeps/unix/sysv/linux/faccessat.c (faccessat): Likewise. * sysdeps/unix/sysv/linux/fchmodat.c (fchmodat): Likewise. * sysdeps/unix/sysv/linux/fcntl.c (do_fcntl): Likewise. * sysdeps/unix/sysv/linux/fstatfs64.c (__fstatfs64): Likewise. * sysdeps/unix/sysv/linux/ftruncate64.c (__ftruncate64): Likewise. * sysdeps/unix/sysv/linux/futimens.c (futimens): Likewise. * sysdeps/unix/sysv/linux/futimes.c (__futimes): Likewise. * sysdeps/unix/sysv/linux/futimesat.c (futimesat): Likewise. * sysdeps/unix/sysv/linux/fxstat.c (__fxstat): Likewise. * sysdeps/unix/sysv/linux/fxstat64.c (___fxstat64): Likewise. * sysdeps/unix/sysv/linux/fxstatat.c (__fxstatat): Likewise. * sysdeps/unix/sysv/linux/fxstatat64.c (__fxstatat64): Likewise. * sysdeps/unix/sysv/linux/gai_sigqueue.c (__gai_sigqueue): Likewise. * sysdeps/unix/sysv/linux/getpriority.c (__getpriority): Likewise. * sysdeps/unix/sysv/linux/getrlimit64.c (__getrlimit64): Likewise. * sysdeps/unix/sysv/linux/llseek.c (__llseek): Likewise. * sysdeps/unix/sysv/linux/lutimes.c (lutimes): Likewise. * sysdeps/unix/sysv/linux/lxstat.c (__lxstat): Likewise. * sysdeps/unix/sysv/linux/lxstat64.c (___lxstat64): Likewise. * sysdeps/unix/sysv/linux/mmap64.c (__mmap64): Likewise. * sysdeps/unix/sysv/linux/mq_close.c (mq_close): Likewise. * sysdeps/unix/sysv/linux/mq_open.c (__mq_open): Likewise. * sysdeps/unix/sysv/linux/mq_unlink.c (mq_unlink): Likewise. * sysdeps/unix/sysv/linux/msgget.c (msgget): Likewise. * sysdeps/unix/sysv/linux/prlimit.c (prlimit): Likewise. * sysdeps/unix/sysv/linux/pt-raise.c (raise): Likewise. * sysdeps/unix/sysv/linux/raise.c (raise): Likewise. * sysdeps/unix/sysv/linux/readahead.c (__readahead): Likewise. * sysdeps/unix/sysv/linux/reboot.c (reboot): Likewise. * sysdeps/unix/sysv/linux/semget.c (semget): Likewise. * sysdeps/unix/sysv/linux/semop.c (semop): Likewise. * sysdeps/unix/sysv/linux/semtimedop.c (semtimedop): Likewise. * sysdeps/unix/sysv/linux/setrlimit64.c (setrlimit64): Likewise. * sysdeps/unix/sysv/linux/shmat.c (shmat): Likewise. * sysdeps/unix/sysv/linux/shmdt.c (shmdt): Likewise. * sysdeps/unix/sysv/linux/shmget.c (shmget): Likewise. * sysdeps/unix/sysv/linux/signalfd.c (signalfd): Likewise. * sysdeps/unix/sysv/linux/sigpending.c (sigpending): Likewise. * sysdeps/unix/sysv/linux/sigprocmask.c ( __sigprocmask): Likewise. * sysdeps/unix/sysv/linux/sigqueue.c (__sigqueue): Likewise. * sysdeps/unix/sysv/linux/speed.c (cfsetospeed): Likewise. * sysdeps/unix/sysv/linux/statfs64.c (__statfs64): Likewise. * sysdeps/unix/sysv/linux/sysctl.c (__sysctl): Likewise. * sysdeps/unix/sysv/linux/tcsendbrk.c (tcsendbreak): Likewise. * sysdeps/unix/sysv/linux/tcsetattr.c (tcsetattr): Likewise. * sysdeps/unix/sysv/linux/timer_getoverr.c (timer_getoverrun): Likewise. * sysdeps/unix/sysv/linux/timer_gettime.c (timer_gettime): Likewise. * sysdeps/unix/sysv/linux/timer_settime.c (timer_settime): Likewise. * sysdeps/unix/sysv/linux/truncate64.c (truncate64): Likewise. * sysdeps/unix/sysv/linux/ustat.c (ustat): Likewise. * sysdeps/unix/sysv/linux/utimensat.c (utimensat): Likewise. * sysdeps/unix/sysv/linux/utimes.c (__utimes): Likewise. * sysdeps/unix/sysv/linux/xmknod.c (__xmknod): Likewise. * sysdeps/unix/sysv/linux/xmknodat.c (__xmknodat): Likewise. * sysdeps/unix/sysv/linux/xstat.c (__xstat): Likewise. * sysdeps/unix/sysv/linux/xstat64.c (___xstat64): Likewise. * sysdeps/unix/sysv/linux/xstatconv.c (__xstat_conv): Likewise. (__xstat64_conv): Likewise. (__xstat32_conv): Likewise. * sysdeps/unix/sysv/linux/sched_getaffinity.c (__sched_getaffinity_new): Add libc_hidden_proto and libc_hidden_def. Use INLINE_SYSCALL_ERROR_RETURN.
Diffstat (limited to 'sysdeps/unix/sysv/linux/faccessat.c')
-rw-r--r--sysdeps/unix/sysv/linux/faccessat.c10
1 files changed, 3 insertions, 7 deletions
diff --git a/sysdeps/unix/sysv/linux/faccessat.c b/sysdeps/unix/sysv/linux/faccessat.c
index 1bb544fd4d..6a0b1b7018 100644
--- a/sysdeps/unix/sysv/linux/faccessat.c
+++ b/sysdeps/unix/sysv/linux/faccessat.c
@@ -35,13 +35,10 @@ faccessat (fd, file, mode, flag)
int flag;
{
if (flag & ~(AT_SYMLINK_NOFOLLOW | AT_EACCESS))
- {
- __set_errno (EINVAL);
- return -1;
- }
+ return INLINE_SYSCALL_ERROR_RETURN (-EINVAL, int, -1);
if ((flag == 0 || ((flag & ~AT_EACCESS) == 0 && ! __libc_enable_secure)))
- return INLINE_SYSCALL (faccessat, 3, fd, file, mode);
+ return INLINE_SYSCALL_RETURN (faccessat, 3, int, fd, file, mode);
struct stat64 stats;
if (__fxstatat64 (_STAT_VER, fd, file, &stats, flag & AT_SYMLINK_NOFOLLOW))
@@ -74,6 +71,5 @@ faccessat (fd, file, mode, flag)
if (granted == mode)
return 0;
- __set_errno (EACCES);
- return -1;
+ return INLINE_SYSCALL_ERROR_RETURN (-EACCES, int, -1);
}