/* sparc assembly program to read in a string and print it backwards */

	.global main
.section ".data"			/* data section */
	.data
	.align 4
str0:	.asciz "Enter a string:	"
	.align 4
str1:	.asciz "%c"	/* format string used by scanf */
	.align 4
str2:	.asciz"\n"

.section ".bss"				/* uninitialized data section */
	.bss
	.align 4
	strbuffer:	 .skip 64		! 64 byte buffer

.section ".text"			/* code section */
	.text
	.align 4
main:
	save %sp,-120,%sp
	/* print prompt string */
	sethi %hi(str0),%o0
	or %o0,%lo(str0),%o0	! mov address of str0 into o0
	call printf
	nop			! pipeline delay slot
	/* use %l1 as pointer to position in buffer, %l0 as counter */
	set strbuffer,%l1	! set is a macro for sethi+or lo
	mov 0,%l0
	/* scanf loop */
scanlp:		
	set str1,%o0
	mov %l1,%o1
	call scanf
	nop

/*	set str0,%o0		! print "\n"
	call printf
	nop
*/	
	add %l0,1,%l0	
	ldub [%l1],%o2		! load (unsigned) byte from buffer to %o2
	cmp %o2,10		! check for carriage return
	bne scanlp
	inc %l1			! macro for add %o1,1,%o1, fills delay slot
	/* at this point l0 holds number of chars+1, o1 points to char past last */
	dec %l0
	dec %l1
	/* print loop:	 */
prlp:	set str1,%o0		! o0 erased after each printf!
	ldub [%l1],%o1
	call printf
	nop
	dec %l1
	dec %l0
	cmp %l0,0
	bge prlp
	nop
	/* print \n to end */
	set str2,%o0
	call printf
	nop

	restore
	mov 1,%g1
	ta 0			! trap to OS