From: Samuel Thibault <samuel.thibault@eu.citrix.com>
Subject: [PATCH] [Mini-OS] Optimize IA64's get_current()
Date: Thu, 17 Jan 2008 13:29:00 +0000
Message-ID: <20080117132900.GA11129@implementation.uk.xensource.com>
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Let gcc access r13 itself, leading to better code

Signed-off-by: Samuel Thibault <samuel.thibault@citrix.com>

diff -r a66bdc82d8fa extras/mini-os/include/ia64/arch_sched.h
--- a/extras/mini-os/include/ia64/arch_sched.h	Wed Jan 16 11:44:41 2008 +0000
+++ b/extras/mini-os/include/ia64/arch_sched.h	Thu Jan 17 12:29:01 2008 +0000
@@ -82,8 +82,7 @@ void arch_switch_threads(struct thread* 
 
 static inline struct thread* get_current(void)
 {
-	struct thread *current;
-	__asm ("mov %0=r13" : "=r" (current));
+	register struct thread *current asm("r13");
 	return current;
 }