MOVW	R9, R13
	RET

TEXT runtime·sigaltstack_trampoline(SB),NOSPLIT,$0
	MOVW	R13, R9
	BIC     $0x7, R13		// align for ELF ABI
	MOVW	4(R0), R1		// arg 2 old
	MOVW	0(R0), R0		// arg 1 new
	BL	libc_sigaltstack(SB)
	CMP	$-1, R0
	BNE	3(PC)
	MOVW	$0, R8			// crash on failure
	MOVW	R8, (R8)
	MOVW	R9, R13
	RET

// syscall calls a function in libc on behalf of the syscall package.

	PUSHL	BP
	MOVL	SP, BP
	SUBL	$8, SP
	MOVL	16(SP), DX		// pointer to args
	MOVL	0(DX), AX
	MOVL	4(DX), BX
	MOVL	AX, 0(SP)		// arg 1 - new
	MOVL	BX, 4(SP)		// arg 2 - old
	CALL	libc_sigaltstack(SB)
	CMPL	AX, $-1
	JNE	2(PC)
	MOVL	$0xf1, 0xf1		// crash on failure
	MOVL	BP, SP
	POPL	BP
	RET

// syscall calls a function in libc on behalf of the syscall package.