diff options
| author | Glauber Costa <gcosta@redhat.com> | 2008-06-24 16:51:59 -0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-07-09 09:14:09 +0200 |
| commit | 663aa96df32af9c4141ef3179282f95c7537643a (patch) | |
| tree | fd8856815bea7ef8b6525f498cbc6f7dc2ded28e /arch/x86/lib/putuser_64.S | |
| parent | 0ada3164031162b4e1b7ff6b36ba8cc80ff7fe96 (diff) | |
x86: change testing logic in putuser_64.S.
Instead of operating over a register we need to put back
into normal state afterwards (the memory position), just
sub from rbx, which is trashed anyway. We can save a few instructions.
Also, this is the i386 way.
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/lib/putuser_64.S')
| -rw-r--r-- | arch/x86/lib/putuser_64.S | 33 |
1 files changed, 12 insertions, 21 deletions
diff --git a/arch/x86/lib/putuser_64.S b/arch/x86/lib/putuser_64.S index ce5fcd5d8c1..a96bd8a5298 100644 --- a/arch/x86/lib/putuser_64.S +++ b/arch/x86/lib/putuser_64.S @@ -46,48 +46,39 @@ ENDPROC(__put_user_1) ENTRY(__put_user_2) CFI_STARTPROC GET_THREAD_INFO(%rbx) - addq $1,%rcx - jc 20f - cmpq TI_addr_limit(%rbx),%rcx - jae 20f - decq %rcx + mov TI_addr_limit(%rbx),%rbx + sub $1, %rbx + cmpq %rbx ,%rcx + jae bad_put_user 2: movw %ax,(%rcx) xorl %eax,%eax ret -20: decq %rcx - jmp bad_put_user CFI_ENDPROC ENDPROC(__put_user_2) ENTRY(__put_user_4) CFI_STARTPROC GET_THREAD_INFO(%rbx) - addq $3,%rcx - jc 30f - cmpq TI_addr_limit(%rbx),%rcx - jae 30f - subq $3,%rcx + mov TI_addr_limit(%rbx),%rbx + sub $3, %rbx + cmp %rbx, %rcx + jae bad_put_user 3: movl %eax,(%rcx) xorl %eax,%eax ret -30: subq $3,%rcx - jmp bad_put_user CFI_ENDPROC ENDPROC(__put_user_4) ENTRY(__put_user_8) CFI_STARTPROC GET_THREAD_INFO(%rbx) - addq $7,%rcx - jc 40f - cmpq TI_addr_limit(%rbx),%rcx - jae 40f - subq $7,%rcx + mov TI_addr_limit(%rbx),%rbx + sub $7, %rbx + cmp %rbx, %rcx + jae bad_put_user 4: movq %rax,(%rcx) xorl %eax,%eax ret -40: subq $7,%rcx - jmp bad_put_user CFI_ENDPROC ENDPROC(__put_user_8) |