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| author | Keir Fraser <keir.fraser@citrix.com> | 2007-11-23 16:23:03 +0000 |
|---|---|---|
| committer | Keir Fraser <keir.fraser@citrix.com> | 2007-11-23 16:23:03 +0000 |
| commit | a222af2ef1f49e5c232466ab162fd606732a9d05 (patch) | |
| tree | ef3eff7c5510e0f1f605353425dd23ae784c4343 /extras/mini-os/include/x86 | |
| parent | bb44bead1012120e08e81ce206612618384481de (diff) | |
| download | xen-a222af2ef1f49e5c232466ab162fd606732a9d05.tar.gz xen-a222af2ef1f49e5c232466ab162fd606732a9d05.tar.bz2 xen-a222af2ef1f49e5c232466ab162fd606732a9d05.zip | |
[Mini-OS] Optimize get_current()
Let gcc perform the computation with SP itself, leading to yet better
code.
Signed-off-by: Samuel Thibault <samuel.thibault@citrix.com>
Diffstat (limited to 'extras/mini-os/include/x86')
| -rw-r--r-- | extras/mini-os/include/x86/arch_sched.h | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/extras/mini-os/include/x86/arch_sched.h b/extras/mini-os/include/x86/arch_sched.h index 6bc47f89d3..7bf0036fac 100644 --- a/extras/mini-os/include/x86/arch_sched.h +++ b/extras/mini-os/include/x86/arch_sched.h @@ -7,10 +7,11 @@ static inline struct thread* get_current(void) { struct thread **current; #ifdef __i386__ - __asm__("andl %%esp,%0; ":"=r" (current) : "0" (~8191UL)); + register unsigned long sp asm("esp"); #else - __asm__("andq %%rsp,%0; ":"=r" (current) : "0" (~8191UL)); + register unsigned long sp asm("rsp"); #endif + current = (void *)(sp & ~8191UL); return *current; } |