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

fusl/arch/mips/atomic.h

Index: fusl/arch/mips/atomic.h
diff --git a/fusl/arch/mips/atomic.h b/fusl/arch/mips/atomic.h
new file mode 100644
index 0000000000000000000000000000000000000000..c82046a81aaefcdbe6361c901755ef687867e274
--- /dev/null
+++ b/fusl/arch/mips/atomic.h
@@ -0,0 +1,205 @@
+#ifndef _INTERNAL_ATOMIC_H
+#define _INTERNAL_ATOMIC_H
+
+#include <stdint.h>
+
+static inline int a_ctz_l(unsigned long x)
+{
+	static const char debruijn32[32] = {
+		0, 1, 23, 2, 29, 24, 19, 3, 30, 27, 25, 11, 20, 8, 4, 13,
+		31, 22, 28, 18, 26, 10, 7, 12, 21, 17, 9, 6, 16, 5, 15, 14
+	};
+	return debruijn32[(x&-x)*0x076be629 >> 27];
+}
+
+static inline int a_ctz_64(uint64_t x)
+{
+	uint32_t y = x;
+	if (!y) {
+		y = x>>32;
+		return 32 + a_ctz_l(y);
+	}
+	return a_ctz_l(y);
+}
+
+static inline int a_cas(volatile int *p, int t, int s)
+{
+	int dummy;
+	__asm__ __volatile__(
+		".set push\n"
+		".set mips2\n"
+		".set noreorder\n"
+		"	sync\n"
+		"1:	ll %0, %2\n"
+		"	bne %0, %3, 1f\n"
+		"	addu %1, %4, $0\n"
+		"	sc %1, %2\n"
+		"	beq %1, $0, 1b\n"
+		"	nop\n"
+		"	sync\n"
+		"1:	\n"
+		".set pop\n"
+		: "=&r"(t), "=&r"(dummy), "+m"(*p) : "r"(t), "r"(s) : "memory" );
+        return t;
+}
+
+static inline void *a_cas_p(volatile void *p, void *t, void *s)
+{
+	return (void *)a_cas(p, (int)t, (int)s);
+}
+
+static inline int a_swap(volatile int *x, int v)
+{
+	int old, dummy;
+	__asm__ __volatile__(
+		".set push\n"
+		".set mips2\n"
+		".set noreorder\n"
+		"	sync\n"
+		"1:	ll %0, %2\n"
+		"	addu %1, %3, $0\n"
+		"	sc %1, %2\n"
+		"	beq %1, $0, 1b\n"
+		"	nop\n"
+		"	sync\n"
+		".set pop\n"
+		: "=&r"(old), "=&r"(dummy), "+m"(*x) : "r"(v) : "memory" );
+        return old;
+}
+
+static inline int a_fetch_add(volatile int *x, int v)
+{
+	int old, dummy;
+	__asm__ __volatile__(
+		".set push\n"
+		".set mips2\n"
+		".set noreorder\n"
+		"	sync\n"
+		"1:	ll %0, %2\n"
+		"	addu %1, %0, %3\n"
+		"	sc %1, %2\n"
+		"	beq %1, $0, 1b\n"
+		"	nop\n"
+		"	sync\n"
+		".set pop\n"
+		: "=&r"(old), "=&r"(dummy), "+m"(*x) : "r"(v) : "memory" );
+        return old;
+}
+
+static inline void a_inc(volatile int *x)
+{
+	int dummy;
+	__asm__ __volatile__(
+		".set push\n"
+		".set mips2\n"
+		".set noreorder\n"
+		"	sync\n"
+		"1:	ll %0, %1\n"
+		"	addu %0, %0, 1\n"
+		"	sc %0, %1\n"
+		"	beq %0, $0, 1b\n"
+		"	nop\n"
+		"	sync\n"
+		".set pop\n"
+		: "=&r"(dummy), "+m"(*x) : : "memory" );
+}
+
+static inline void a_dec(volatile int *x)
+{
+	int dummy;
+	__asm__ __volatile__(
+		".set push\n"
+		".set mips2\n"
+		".set noreorder\n"
+		"	sync\n"
+		"1:	ll %0, %1\n"
+		"	subu %0, %0, 1\n"
+		"	sc %0, %1\n"
+		"	beq %0, $0, 1b\n"
+		"	nop\n"
+		"	sync\n"
+		".set pop\n"
+		: "=&r"(dummy), "+m"(*x) : : "memory" );
+}
+
+static inline void a_store(volatile int *p, int x)
+{
+	__asm__ __volatile__(
+		".set push\n"
+		".set mips2\n"
+		".set noreorder\n"
+		"	sync\n"
+		"	sw %1, %0\n"
+		"	sync\n"
+		".set pop\n"
+		: "+m"(*p) : "r"(x) : "memory" );
+}
+
+#define a_spin a_barrier
+
+static inline void a_barrier()
+{
+	a_cas(&(int){0}, 0, 0);
+}
+
+static inline void a_crash()
+{
+	*(volatile char *)0=0;
+}
+
+static inline void a_and(volatile int *p, int v)
+{
+	int dummy;
+	__asm__ __volatile__(
+		".set push\n"
+		".set mips2\n"
+		".set noreorder\n"
+		"	sync\n"
+		"1:	ll %0, %1\n"
+		"	and %0, %0, %2\n"
+		"	sc %0, %1\n"
+		"	beq %0, $0, 1b\n"
+		"	nop\n"
+		"	sync\n"
+		".set pop\n"
+		: "=&r"(dummy), "+m"(*p) : "r"(v) : "memory" );
+}
+
+static inline void a_or(volatile int *p, int v)
+{
+	int dummy;
+	__asm__ __volatile__(
+		".set push\n"
+		".set mips2\n"
+		".set noreorder\n"
+		"	sync\n"
+		"1:	ll %0, %1\n"
+		"	or %0, %0, %2\n"
+		"	sc %0, %1\n"
+		"	beq %0, $0, 1b\n"
+		"	nop\n"
+		"	sync\n"
+		".set pop\n"
+		: "=&r"(dummy), "+m"(*p) : "r"(v) : "memory" );
+}
+
+static inline void a_or_l(volatile void *p, long v)
+{
+	a_or(p, v);
+}
+
+static inline void a_and_64(volatile uint64_t *p, uint64_t v)
+{
+	union { uint64_t v; uint32_t r[2]; } u = { v };
+	a_and((int *)p, u.r[0]);
+	a_and((int *)p+1, u.r[1]);
+}
+
+static inline void a_or_64(volatile uint64_t *p, uint64_t v)
+{
+	union { uint64_t v; uint32_t r[2]; } u = { v };
+	a_or((int *)p, u.r[0]);
+	a_or((int *)p+1, u.r[1]);
+}
+
+#endif