[5/6] Optimize i386 syscall inlining
Commit Message
On Wed, Oct 21, 2015 at 8:01 AM, Andreas Schwab <schwab@suse.de> wrote:
> "H.J. Lu" <hjl.tools@gmail.com> writes:
>
>> Which GCC are you using?
>
> https://build.opensuse.org/package/show/openSUSE:Factory/gcc5
>
> Andreas.
I am testing this patch and will check it in if it passes check.
Comments
On Wed, 21 Oct 2015, H.J. Lu wrote:
> On Wed, Oct 21, 2015 at 8:01 AM, Andreas Schwab <schwab@suse.de> wrote:
> > "H.J. Lu" <hjl.tools@gmail.com> writes:
> >
> >> Which GCC are you using?
> >
> > https://build.opensuse.org/package/show/openSUSE:Factory/gcc5
> >
> > Andreas.
>
> I am testing this patch and will check it in if it passes check.
Do you also need to change libc-do-syscall.S to build __libc_do_syscall
for the profiling libc?
b/sysdeps/unix/sysv/linux/i386/sysdep.h
@@ -229,9 +229,15 @@ extern int __syscall_error (int)
/* Since GCC 5 and above can properly spill %ebx with PIC when needed,
we can inline syscalls with 6 arguments if GCC 5 or above is used
- to compile glibc. */
+ to compile glibc. Disable GCC 5 optimization when compiling for
+ profiling since asm ("ebp") can't be used to put the 6th argument
+ in %ebp for syscall. */
-#if !__GNUC_PREREQ (5,0)
+#if __GNUC_PREREQ (5,0) && !defined PROF
+# define OPTIMIZE_FOR_GCC_5
+#endif
+
+#ifndef OPTIMIZE_FOR_GCC_5
/* We need some help from the assembler to generate optimal code. We
define some macros here which later will be used. */
asm (".L__X'%ebx = 1\n\t"
@@ -328,7 +334,7 @@ struct libc_do_syscall_args
INTERNAL_SYSCALL_MAIN_INLINE(name, err, 5, args)
/* Each object using 6-argument inline syscalls must include a
definition of __libc_do_syscall. */
-#if __GNUC_PREREQ (5,0)
+#ifdef OPTIMIZE_FOR_GCC_5
# define INTERNAL_SYSCALL_MAIN_6(name, err, args...) \
INTERNAL_SYSCALL_MAIN_INLINE(name, err, 6, args)
#else /* GCC 5 */
@@ -353,7 +359,7 @@ struct libc_do_syscall_args
INTERNAL_SYSCALL_MAIN_##nr (name, err, args); \
(int) resultvar; })
#ifdef I386_USE_SYSENTER
-# if __GNUC_PREREQ (5,0)
+# ifdef OPTIMIZE_FOR_GCC_5
# ifdef SHARED
# define INTERNAL_SYSCALL_MAIN_INLINE(name, err, nr, args...) \
LOADREGS_##nr(args) \
@@ -437,7 +443,7 @@ struct libc_do_syscall_args
# endif
# endif /* GCC 5 */
#else
-# if __GNUC_PREREQ (5,0)
+# ifdef OPTIMIZE_FOR_GCC_5
# define INTERNAL_SYSCALL_MAIN_INLINE(name, err, nr, args...) \
LOADREGS_##nr(args) \
asm volatile ( \
@@ -539,7 +545,7 @@ struct libc_do_syscall_args
# define RESTOREARGS_5
#endif
-#if __GNUC_PREREQ (5,0)
+#ifdef OPTIMIZE_FOR_GCC_5
# define LOADREGS_0()
# define ASMARGS_0()
# define LOADREGS_1(arg1) \
@@ -606,7 +612,7 @@ struct libc_do_syscall_args
#endif
/* Consistency check for position-independent code. */
-#if defined __PIC__ && !__GNUC_PREREQ (5,0)
+#if defined __PIC__ && !defined OPTIMIZE_FOR_GCC_5
# define check_consistency() \
({ int __res; \
__asm__ __volatile__