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

fusl/arch/arm/src/arm/atomics.s

Index: fusl/arch/arm/src/arm/atomics.s
diff --git a/fusl/arch/arm/src/arm/atomics.s b/fusl/arch/arm/src/arm/atomics.s
new file mode 100644
index 0000000000000000000000000000000000000000..5c5b0e3ed481ee6f78a97509bb7892acac27b1e6
--- /dev/null
+++ b/fusl/arch/arm/src/arm/atomics.s
@@ -0,0 +1,111 @@
+.syntax unified
+.text
+
+.global __a_barrier
+.hidden __a_barrier
+.type __a_barrier,%function
+__a_barrier:
+	ldr ip,1f
+	ldr ip,[pc,ip]
+	add pc,pc,ip
+1:	.word __a_barrier_ptr-1b
+.global __a_barrier_dummy
+.hidden __a_barrier_dummy
+__a_barrier_dummy:
+	bx lr
+.global __a_barrier_oldkuser
+.hidden __a_barrier_oldkuser
+__a_barrier_oldkuser:
+	push {r0,r1,r2,r3,ip,lr}
+	mov r1,r0
+	mov r2,sp
+	ldr ip,=0xffff0fc0
+	mov lr,pc
+	mov pc,ip
+	pop {r0,r1,r2,r3,ip,lr}
+	bx lr
+.global __a_barrier_v6
+.hidden __a_barrier_v6
+__a_barrier_v6:
+	mcr p15,0,r0,c7,c10,5
+	bx lr
+.global __a_barrier_v7
+.hidden __a_barrier_v7
+__a_barrier_v7:
+	.word 0xf57ff05b        /* dmb ish */
+	bx lr
+
+.global __a_cas
+.hidden __a_cas
+.type __a_cas,%function
+__a_cas:
+	ldr ip,1f
+	ldr ip,[pc,ip]
+	add pc,pc,ip
+1:	.word __a_cas_ptr-1b
+.global __a_cas_dummy
+.hidden __a_cas_dummy
+__a_cas_dummy:
+	mov r3,r0
+	ldr r0,[r2]
+	subs r0,r3,r0
+	streq r1,[r2]
+	bx lr
+.global __a_cas_v6
+.hidden __a_cas_v6
+__a_cas_v6:
+	mov r3,r0
+	mcr p15,0,r0,c7,c10,5
+1:	.word 0xe1920f9f        /* ldrex r0,[r2] */
+	subs r0,r3,r0
+	.word 0x01820f91        /* strexeq r0,r1,[r2] */
+	teqeq r0,#1
+	beq 1b
+	mcr p15,0,r0,c7,c10,5
+	bx lr
+.global __a_cas_v7
+.hidden __a_cas_v7
+__a_cas_v7:
+	mov r3,r0
+	.word 0xf57ff05b        /* dmb ish */
+1:	.word 0xe1920f9f        /* ldrex r0,[r2] */
+	subs r0,r3,r0
+	.word 0x01820f91        /* strexeq r0,r1,[r2] */
+	teqeq r0,#1
+	beq 1b
+	.word 0xf57ff05b        /* dmb ish */
+	bx lr
+
+.global __aeabi_read_tp
+.type __aeabi_read_tp,%function
+__aeabi_read_tp:
+
+.global __a_gettp
+.hidden __a_gettp
+.type __a_gettp,%function
+__a_gettp:
+	ldr r0,1f
+	ldr r0,[pc,r0]
+	add pc,pc,r0
+1:	.word __a_gettp_ptr-1b
+.global __a_gettp_dummy
+.hidden __a_gettp_dummy
+__a_gettp_dummy:
+	mrc p15,0,r0,c13,c0,3
+	bx lr
+
+.data
+.global __a_barrier_ptr
+.hidden __a_barrier_ptr
+__a_barrier_ptr:
+	.word 0
+
+.global __a_cas_ptr
+.hidden __a_cas_ptr
+__a_cas_ptr:
+	.word 0
+
+.global __a_gettp_ptr
+.hidden __a_gettp_ptr
+__a_gettp_ptr:
+	.word 0