xref: /aosp_15_r20/external/musl/src/thread/riscv32/clone.s (revision c9945492fdd68bbe62686c5b452b4dc1be3f8453)
1*c9945492SAndroid Build Coastguard Worker# __clone(func, stack, flags, arg, ptid, tls, ctid)
2*c9945492SAndroid Build Coastguard Worker#           a0,    a1,    a2,  a3,   a4,  a5,   a6
3*c9945492SAndroid Build Coastguard Worker
4*c9945492SAndroid Build Coastguard Worker# syscall(SYS_clone, flags, stack, ptid, tls, ctid)
5*c9945492SAndroid Build Coastguard Worker#                a7     a0,    a1,   a2,  a3,   a4
6*c9945492SAndroid Build Coastguard Worker
7*c9945492SAndroid Build Coastguard Worker.global __clone
8*c9945492SAndroid Build Coastguard Worker.type  __clone, %function
9*c9945492SAndroid Build Coastguard Worker__clone:
10*c9945492SAndroid Build Coastguard Worker	# Save func and arg to stack
11*c9945492SAndroid Build Coastguard Worker	addi a1, a1, -16
12*c9945492SAndroid Build Coastguard Worker	sw a0, 0(a1)
13*c9945492SAndroid Build Coastguard Worker	sw a3, 4(a1)
14*c9945492SAndroid Build Coastguard Worker
15*c9945492SAndroid Build Coastguard Worker	# Call SYS_clone
16*c9945492SAndroid Build Coastguard Worker	mv a0, a2
17*c9945492SAndroid Build Coastguard Worker	mv a2, a4
18*c9945492SAndroid Build Coastguard Worker	mv a3, a5
19*c9945492SAndroid Build Coastguard Worker	mv a4, a6
20*c9945492SAndroid Build Coastguard Worker	li a7, 220 # SYS_clone
21*c9945492SAndroid Build Coastguard Worker	ecall
22*c9945492SAndroid Build Coastguard Worker
23*c9945492SAndroid Build Coastguard Worker	beqz a0, 1f
24*c9945492SAndroid Build Coastguard Worker	# Parent
25*c9945492SAndroid Build Coastguard Worker	ret
26*c9945492SAndroid Build Coastguard Worker
27*c9945492SAndroid Build Coastguard Worker	# Child
28*c9945492SAndroid Build Coastguard Worker1:      lw a1, 0(sp)
29*c9945492SAndroid Build Coastguard Worker	lw a0, 4(sp)
30*c9945492SAndroid Build Coastguard Worker	jalr a1
31*c9945492SAndroid Build Coastguard Worker
32*c9945492SAndroid Build Coastguard Worker	# Exit
33*c9945492SAndroid Build Coastguard Worker	li a7, 93 # SYS_exit
34*c9945492SAndroid Build Coastguard Worker	ecall
35