musl/src/internal/arm/syscall.s

.global __syscall
.hidden __syscall
.type __syscall,%function
__syscall:
	mov ip,sp
	stmfd sp!,{r4,r5,r6,r7}
	mov r7,r0
	mov r0,r1
	mov r1,r2
	mov r2,r3
	ldmfd ip,{r3,r4,r5,r6}
	svc 0
	ldmfd sp!,{r4,r5,r6,r7}
	tst lr,#1
	moveq pc,lr
	bx lr
initial commit of the arm port this port assumes eabi calling conventions, eabi linux syscall convention, and presence of the kernel helpers at 0xffff0f?0 needed for threads support. otherwise it makes very few assumptions, and the code should work even on armv4 without thumb support, as well as on systems with thumb interworking. the bits headers declare this a little endian system, but as far as i can tell the code should work equally well on big endian. some small details are probably broken; so far, testing has been limited to qemu/aboriginal linux. 2011-09-18 16:44:54 -04:00			`.global __syscall`
fix inconsistent visibility for internal syscall symbols 2015-04-14 13:48:20 -04:00			`.hidden __syscall`
initial commit of the arm port this port assumes eabi calling conventions, eabi linux syscall convention, and presence of the kernel helpers at 0xffff0f?0 needed for threads support. otherwise it makes very few assumptions, and the code should work even on armv4 without thumb support, as well as on systems with thumb interworking. the bits headers declare this a little endian system, but as far as i can tell the code should work equally well on big endian. some small details are probably broken; so far, testing has been limited to qemu/aboriginal linux. 2011-09-18 16:44:54 -04:00			`.type __syscall,%function`
			`__syscall:`
			`mov ip,sp`
			`stmfd sp!,{r4,r5,r6,r7}`
			`mov r7,r0`
			`mov r0,r1`
			`mov r1,r2`
			`mov r2,r3`
			`ldmfd ip,{r3,r4,r5,r6}`
			`svc 0`
			`ldmfd sp!,{r4,r5,r6,r7}`
			`tst lr,#1`
			`moveq pc,lr`
			`bx lr`