patch-2.1.31 linux/include/asm-alpha/atomic.h

• Lines: 146
• Date: Fri Mar 28 10:52:25 1997
• Orig file: v2.1.30/linux/include/asm-alpha/atomic.h
• Orig date: Wed Sep 11 11:41:51 1996

diff -u --recursive --new-file v2.1.30/linux/include/asm-alpha/atomic.h linux/include/asm-alpha/atomic.h
@@ -1,14 +1,16 @@
-#ifndef __ARCH_ALPHA_ATOMIC__
-#define __ARCH_ALPHA_ATOMIC__
+#ifndef _ALPHA_ATOMIC_H
+#define _ALPHA_ATOMIC_H
 
 /*
  * Atomic operations that C can't guarantee us.  Useful for
  * resource counting etc...
  *
- * But use these as seldom as possible since they are much more slower
+ * But use these as seldom as possible since they are much slower
  * than regular operations.
  */
 
+typedef int atomic_t;
+
 /*
  * Make sure gcc doesn't try to be clever and move things around
  * on us. We need to use _exactly_ the address the user gave us,
@@ -16,38 +18,40 @@
  */
 #define __atomic_fool_gcc(x) (*(struct { int a[100]; } *)x)
 
-typedef int atomic_t;
+/*
+ * To get proper branch prediction for the main line, we must branch
+ * forward to code at the end of this object's .text section, then
+ * branch back to restart the operation.
+ */
 
 extern __inline__ void atomic_add(atomic_t i, atomic_t * v)
 {
 	unsigned long temp;
 	__asm__ __volatile__(
-		"\n1:\t"
-		"ldl_l %0,%1\n\t"
-		"addl %0,%2,%0\n\t"
-		"stl_c %0,%1\n\t"
-		"beq %0,1b\n"
-		"2:"
-		:"=&r" (temp),
-		 "=m" (__atomic_fool_gcc(v))
-		:"Ir" (i),
-		 "m" (__atomic_fool_gcc(v)));
+	"1:	ldl_l %0,%1\n"
+	"	addl %0,%2,%0\n"
+	"	stl_c %0,%1\n"
+	"	beq %0,2f\n"
+	".text 2\n"
+	"2:	br 1b\n"
+	".text"
+	:"=&r" (temp), "=m" (__atomic_fool_gcc(v))
+	:"Ir" (i), "m" (__atomic_fool_gcc(v)));
 }
 
 extern __inline__ void atomic_sub(atomic_t i, atomic_t * v)
 {
 	unsigned long temp;
 	__asm__ __volatile__(
-		"\n1:\t"
-		"ldl_l %0,%1\n\t"
-		"subl %0,%2,%0\n\t"
-		"stl_c %0,%1\n\t"
-		"beq %0,1b\n"
-		"2:"
-		:"=&r" (temp),
-		 "=m" (__atomic_fool_gcc(v))
-		:"Ir" (i),
-		 "m" (__atomic_fool_gcc(v)));
+	"1:	ldl_l %0,%1\n"
+	"	subl %0,%2,%0\n"
+	"	stl_c %0,%1\n"
+	"	beq %0,2f\n"
+	".text 2\n"
+	"2:	br 1b\n"
+	".text"
+	:"=&r" (temp), "=m" (__atomic_fool_gcc(v))
+	:"Ir" (i), "m" (__atomic_fool_gcc(v)));
 }
 
 /*
@@ -57,18 +61,16 @@
 {
 	long temp, result;
 	__asm__ __volatile__(
-		"\n1:\t"
-		"ldl_l %0,%1\n\t"
-		"addl %0,%3,%0\n\t"
-		"bis %0,%0,%2\n\t"
-		"stl_c %0,%1\n\t"
-		"beq %0,1b\n"
-		"2:"
-		:"=&r" (temp),
-		 "=m" (__atomic_fool_gcc(v)),
-		 "=&r" (result)
-		:"Ir" (i),
-		 "m" (__atomic_fool_gcc(v)));
+	"1:	ldl_l %0,%1\n"
+	"	addl %0,%3,%0\n"
+	"	mov %0,%2\n"
+	"	stl_c %0,%1\n"
+	"	beq %0,2f\n"
+	".text 2\n"
+	"2:	br 1b\n"
+	".text"
+	:"=&r" (temp), "=m" (__atomic_fool_gcc(v)), "=&r" (result)
+	:"Ir" (i), "m" (__atomic_fool_gcc(v)));
 	return result;
 }
 
@@ -76,18 +78,16 @@
 {
 	long temp, result;
 	__asm__ __volatile__(
-		"\n1:\t"
-		"ldl_l %0,%1\n\t"
-		"subl %0,%3,%0\n\t"
-		"bis %0,%0,%2\n\t"
-		"stl_c %0,%1\n\t"
-		"beq %0,1b\n"
-		"2:"
-		:"=&r" (temp),
-		 "=m" (__atomic_fool_gcc(v)),
-		 "=&r" (result)
-		:"Ir" (i),
-		 "m" (__atomic_fool_gcc(v)));
+	"1:	ldl_l %0,%1\n"
+	"	subl %0,%3,%0\n"
+	"	mov %0,%2\n"
+	"	stl_c %0,%1\n"
+	"	beq %0,2f\n"
+	".text 2\n"
+	"2:	br 1b\n"
+	".text"
+	:"=&r" (temp), "=m" (__atomic_fool_gcc(v)), "=&r" (result)
+	:"Ir" (i), "m" (__atomic_fool_gcc(v)));
 	return result;
 }
 
@@ -100,4 +100,4 @@
 #define atomic_inc(v) atomic_add(1,(v))
 #define atomic_dec(v) atomic_sub(1,(v))
 
-#endif
+#endif /* _ALPHA_ATOMIC_H */