Add a "fork" of musl as //fusl.

fusl/arch/aarch64/atomic.h

Index: fusl/arch/aarch64/atomic.h
diff --git a/fusl/arch/aarch64/atomic.h b/fusl/arch/aarch64/atomic.h
new file mode 100644
index 0000000000000000000000000000000000000000..e7c82c2e26289b200dacf9703ce5e9ce26b2b0af
--- /dev/null
+++ b/fusl/arch/aarch64/atomic.h
@@ -0,0 +1,206 @@
+#ifndef _INTERNAL_ATOMIC_H
+#define _INTERNAL_ATOMIC_H
+
+#include <stdint.h>
+
+static inline int a_ctz_64(uint64_t x)
+{
+	__asm__(
+		"	rbit %0, %1\n"
+		"	clz %0, %0\n"
+		: "=r"(x) : "r"(x));
+	return x;
+}
+
+static inline int a_ctz_l(unsigned long x)
+{
+	return a_ctz_64(x);
+}
+
+static inline void a_barrier()
+{
+	__asm__ __volatile__("dmb ish");
+}
+
+static inline void *a_cas_p(volatile void *p, void *t, void *s)
+{
+	void *old;
+	__asm__ __volatile__(
+		"	dmb ish\n"
+		"1:	ldxr %0,%3\n"
+		"	cmp %0,%1\n"
+		"	b.ne 1f\n"
+		"	stxr %w0,%2,%3\n"
+		"	cbnz %w0,1b\n"
+		"	mov %0,%1\n"
+		"1:	dmb ish\n"
+		: "=&r"(old)
+		: "r"(t), "r"(s), "Q"(*(long*)p)
+		: "memory", "cc");
+	return old;
+}
+
+static inline int a_cas(volatile int *p, int t, int s)
+{
+	int old;
+	__asm__ __volatile__(
+		"	dmb ish\n"
+		"1:	ldxr %w0,%3\n"
+		"	cmp %w0,%w1\n"
+		"	b.ne 1f\n"
+		"	stxr %w0,%w2,%3\n"
+		"	cbnz %w0,1b\n"
+		"	mov %w0,%w1\n"
+		"1:	dmb ish\n"
+		: "=&r"(old)
+		: "r"(t), "r"(s), "Q"(*p)
+		: "memory", "cc");
+	return old;
+}
+
+static inline int a_swap(volatile int *x, int v)
+{
+	int old, tmp;
+	__asm__ __volatile__(
+		"	dmb ish\n"
+		"1:	ldxr %w0,%3\n"
+		"	stxr %w1,%w2,%3\n"
+		"	cbnz %w1,1b\n"
+		"	dmb ish\n"
+		: "=&r"(old), "=&r"(tmp)
+		: "r"(v), "Q"(*x)
+		: "memory", "cc" );
+	return old;
+}
+
+static inline int a_fetch_add(volatile int *x, int v)
+{
+	int old, tmp;
+	__asm__ __volatile__(
+		"	dmb ish\n"
+		"1:	ldxr %w0,%3\n"
+		"	add %w0,%w0,%w2\n"
+		"	stxr %w1,%w0,%3\n"
+		"	cbnz %w1,1b\n"
+		"	dmb ish\n"
+		: "=&r"(old), "=&r"(tmp)
+		: "r"(v), "Q"(*x)
+		: "memory", "cc" );
+	return old-v;
+}
+
+static inline void a_inc(volatile int *x)
+{
+	int tmp, tmp2;
+	__asm__ __volatile__(
+		"	dmb ish\n"
+		"1:	ldxr %w0,%2\n"
+		"	add %w0,%w0,#1\n"
+		"	stxr %w1,%w0,%2\n"
+		"	cbnz %w1,1b\n"
+		"	dmb ish\n"
+		: "=&r"(tmp), "=&r"(tmp2)
+		: "Q"(*x)
+		: "memory", "cc" );
+}
+
+static inline void a_dec(volatile int *x)
+{
+	int tmp, tmp2;
+	__asm__ __volatile__(
+		"	dmb ish\n"
+		"1:	ldxr %w0,%2\n"
+		"	sub %w0,%w0,#1\n"
+		"	stxr %w1,%w0,%2\n"
+		"	cbnz %w1,1b\n"
+		"	dmb ish\n"
+		: "=&r"(tmp), "=&r"(tmp2)
+		: "Q"(*x)
+		: "memory", "cc" );
+}
+
+static inline void a_and_64(volatile uint64_t *p, uint64_t v)
+{
+	int tmp, tmp2;
+	__asm__ __volatile__(
+		"	dmb ish\n"
+		"1:	ldxr %0,%3\n"
+		"	and %0,%0,%2\n"
+		"	stxr %w1,%0,%3\n"
+		"	cbnz %w1,1b\n"
+		"	dmb ish\n"
+		: "=&r"(tmp), "=&r"(tmp2)
+		: "r"(v), "Q"(*p)
+		: "memory", "cc" );
+}
+
+static inline void a_and(volatile int *p, int v)
+{
+	int tmp, tmp2;
+	__asm__ __volatile__(
+		"	dmb ish\n"
+		"1:	ldxr %w0,%3\n"
+		"	and %w0,%w0,%w2\n"
+		"	stxr %w1,%w0,%3\n"
+		"	cbnz %w1,1b\n"
+		"	dmb ish\n"
+		: "=&r"(tmp), "=&r"(tmp2)
+		: "r"(v), "Q"(*p)
+		: "memory", "cc" );
+}
+
+static inline void a_or_64(volatile uint64_t *p, uint64_t v)
+{
+	int tmp, tmp2;
+	__asm__ __volatile__(
+		"	dmb ish\n"
+		"1:	ldxr %0,%3\n"
+		"	orr %0,%0,%2\n"
+		"	stxr %w1,%0,%3\n"
+		"	cbnz %w1,1b\n"
+		"	dmb ish\n"
+		: "=&r"(tmp), "=&r"(tmp2)
+		: "r"(v), "Q"(*p)
+		: "memory", "cc" );
+}
+
+static inline void a_or_l(volatile void *p, long v)
+{
+	return a_or_64(p, v);
+}
+
+static inline void a_or(volatile int *p, int v)
+{
+	int tmp, tmp2;
+	__asm__ __volatile__(
+		"	dmb ish\n"
+		"1:	ldxr %w0,%3\n"
+		"	orr %w0,%w0,%w2\n"
+		"	stxr %w1,%w0,%3\n"
+		"	cbnz %w1,1b\n"
+		"	dmb ish\n"
+		: "=&r"(tmp), "=&r"(tmp2)
+		: "r"(v), "Q"(*p)
+		: "memory", "cc" );
+}
+
+static inline void a_store(volatile int *p, int x)
+{
+	__asm__ __volatile__(
+		"	dmb ish\n"
+		"	str %w1,%0\n"
+		"	dmb ish\n"
+		: "=m"(*p)
+		: "r"(x)
+		: "memory", "cc" );
+}
+
+#define a_spin a_barrier
+
+static inline void a_crash()
+{
+	*(volatile char *)0=0;
+}
+
+
+#endif